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Park SS, Kang H, Kim YH, Kim JH. Different tumor growth pattern of clinically nonfunctioning pituitary neuroendocrine tumor according to sex and age: a longitudinal study. J Endocrinol Invest 2024:10.1007/s40618-024-02303-8. [PMID: 38310625 DOI: 10.1007/s40618-024-02303-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 01/02/2024] [Indexed: 02/06/2024]
Abstract
PURPOSE Asymptomatic patients with clinically non-functional pituitary neuroendocrine tumors (CNF-PitNETs) are usually followed up. However, the natural course of CNF-PitNETs according to sex and age remains unclear. Therefore, this study assessed growth patterns of CNF-PitNETs according to sex and age. METHODS In this longitudinal study, we enrolled 431 consecutive patients with CNF-PitNETs who were treated at Seoul National University Hospital from 1997 to 2021. The patients underwent hormone function testing and visual field testing, and were subsequently followed up with imaging over a median duration of 66 months. RESULTS The median age of the patients was 53.0 years, and 37.1% (n = 160) were men. Men were older and harbored more macroadenomas than women. The annual tumor volume change was higher in men than in women (0.21 vs. 0.04 cm3/year, P < 0.001). The estimated cutoff value of age for significant tumor growth was 51 years. In men, the annual tumor volume change was similar across all age groups. In women, those aged ≤ 50 years showed significantly lower annual tumor volume change than those aged > 50 years (0.01, 0.11, and 0.17 cm3/year, P = 0.001). When comparing sexes within the same age group, the annual tumor volume changes was significantly lower for women than for men, only in patients aged ≤ 50 years (0.01 vs. 0.15 cm3/year, P < 0.001). CONCLUSIONS Among patients with CNF-PitNET, tumor growth was slower in women aged ≤ 50 years than in men and women aged > 50. These findings may guide the customization of surveillance strategies for CNF-PitNETs according to sex and age.
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Affiliation(s)
- S S Park
- Department of Internal Medicine, Seoul National University College of Medicine, 101 Dae-hak ro, Seoul, 03080, Korea
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Pituitary Center, Seoul National University Hospital, Seoul, Korea
| | - H Kang
- Pituitary Center, Seoul National University Hospital, Seoul, Korea
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, 101 Dae-hak ro, Seoul, 03080, Korea
| | - Y H Kim
- Pituitary Center, Seoul National University Hospital, Seoul, Korea.
- Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, 101 Dae-hak ro, Seoul, 03080, Korea.
| | - J H Kim
- Department of Internal Medicine, Seoul National University College of Medicine, 101 Dae-hak ro, Seoul, 03080, Korea.
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
- Pituitary Center, Seoul National University Hospital, Seoul, Korea.
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Garcia DA, Remmes N, Sarkaria JN, Park SS, Grams M. Comparing Acute Oral Mucosa Toxicity Associated with Minibeam and Conventional Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:e230. [PMID: 37784925 DOI: 10.1016/j.ijrobp.2023.06.1144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Acute oral mucosa toxicity is associated with ulceration, severe pain, and nutritional deficiencies that may lead to treatment interruptions and a decreased quality of life for head and neck cancer patients. Minibeam radiotherapy (MRT) is a type of spatially fractionated radiotherapy that delivers an alternating pattern of sub-millimeter wide peaks of high dose immediately adjacent to much lower valley doses. By delivering a non-uniform dose distribution, MRT allows for elevated peak doses while maintaining extraordinary normal tissue tolerance. In this study, we used an acute oral mucosa toxicity mouse model to test the hypothesis that MRT provides superior tissue sparing compared to conventional radiotherapy (CRT). MATERIALS/METHODS A total of 33 female C57BLJ6 mice were randomized by body weight (BW) across two CRT groups (n = 4/group) receiving open field radiation of 16 and 20 Gy and five MRT groups (n = 5/group) receiving peak:valley doses of 48:8, 72:12, 96:16, 96:8, and 152:8 Gy. All radiation was given in one fraction. The CRT groups were irradiated with a 10 mm circular field using a 225 kVp PA x-ray beam encompassing the oral cavity and oropharynx. The MRT groups were irradiated with the same arrangement, but the beam was collimated into 0.5 mm wide minibeams spaced 1.1 mm center-to-center using tungsten collimators of 0.5, 1, and 2.5 mm thickness to deliver peak-to-valley ratios (PVRs) of 6:1, 12:1, and 19:1. Acute effects in the oral mucosa were studied using changes in BW as a surrogate for clinically significant oral mucositis. BWs were measured daily starting on the day of treatment, and BW changes were computed relative to the day of treatment. The toxicity endpoint was defined such that mice losing >20% BW were humanely euthanized. RESULTS Doses of 20 Gy CRT and 96:16 Gy MRT were highly toxic, with all animals in these groups reaching the toxicity endpoint between 9-11 days post-RT, compared to only one animal in the 16 Gy CRT group, and no animals in the other MRT groups. The BWs of all surviving animals returned to baseline within 15 days post-RT. The groups 48:8, 96:8, and 152:8 Gy showed similar BW loss and full recovery patterns. Additionally, the groups 48:8, 72:12, and 96:16 Gy showed that, for the same PVR, increasing the valley dose resulted in increased BW loss. Lastly, animals did not tolerate 96:16 Gy, but those in the 96:8 Gy group fully recovered. CONCLUSION Despite the extreme toxicity caused by 20 Gy CRT, animals in the MRT groups tolerated peak doses up to 152 Gy when the valley dose was 8 Gy. These results confirm the superior normal tissue sparing capacity of MRT compared to CRT in an oral mucosa mouse model. We delivered tolerable MRT peak doses an order of magnitude larger than toxic CRT doses. Importantly, our results suggest that valley dose is the most useful parameter to assess acute toxicity when using MRT. Our data may prove useful for eventual clinical applications of MRT in head and neck cancers.
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Affiliation(s)
- D A Garcia
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN; Mayo Clinic College of Medicine and Science, Rochester, MN
| | - N Remmes
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - J N Sarkaria
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - M Grams
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
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Laughlin BS, Corbin KS, Thorpe CS, Toesca DAS, Golafshar MA, McGee LA, Halyard M, Mutter RW, Keole SR, Park SS, Shumway D, Vallow LA, Vern-Gross TZ, Wong WW, DeWees TA, Vargas CE. Physician and Patient-Reported Outcomes of a Phase III Trial of Ultra-Hypofractionated vs. Moderate Hypofractionated Radiotherapy to the Whole Breast after Breast-Conserving Surgery. Int J Radiat Oncol Biol Phys 2023; 117:S6. [PMID: 37784534 DOI: 10.1016/j.ijrobp.2023.06.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To report a final analysis evaluating physician and patient-reported outcomes of early breast cancer patients receiving moderate hypofractionation or ultra-hypofractionated whole breast radiotherapy (RT). MATERIALS/METHODS Between April 4, 2018, and February 11, 2020, patients with localized breast cancer (T1-T3, N0-N1, and M0) managed with breast-conserving surgery (BCS) were enrolled. Patients were randomized to receive whole breast RT with moderate hypofractionation to 40 Gy in 15 fractions (Arm A) or ultra-hypofractionation to 25 Gy in 5 fractions (Arm B). An optional concurrent integrated boost to 48 Gy on Arm A or 30 Gy on Arm B was allowed. Early toxicity (<3 months), late toxicity (> 3 months), quality of life (QOL), cosmesis, Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), and deterioration of cosmesis were analyzed. RESULTS One hundred and seven patients were randomized to moderate hypofractionation (n = 54) or ultra-hypofractionation (n = 53). With a median follow-up of 36 months, no significant differences in patient characteristics were noted between the two arms. There were no patients with a grade ≥3 or higher toxicity. Grade 2 toxicities were 7.4% in Arm A and 7.5% in Arm B, and primarily consisted of radiation dermatitis (6 patients), fibrosis (1 patient) and lymphedema (1 patient). The average Harvard Cosmesis score and overall QoL were similar between arms at all time points, with no patients developing cosmetic deterioration. Patient-reported moderate to severe radiation skin burns were more commonly reported in Arm A (21.05%) vs. Arm B (6.25%) at the end of treatment (EOT) (p = 0.078). At EOT, patients receiving moderate hypofractionation had higher mean toxicity scores in breast tenderness (2.66 vs. 1.5, p = 0.018), skin flaking or peeling (0.63 vs. 0.06, p = 0.035), blistering (0.74 vs. 0.06, p = 0.028), pruritis (2.53 vs. 0.87, p < 0.001), erythema (4.24 vs. 2.0, p <0.001), telangiectasias (1.0 vs. 0.28, p = 0.021). Additionally, patients receiving moderate hypofractionation reported significantly worse changes from baseline at EOT in breast tenderness (-2.25 vs. -.86, p = 0.02), telangiectasia (-0.81 vs. 0.18, p = 0.012), skin discoloration (-4.31 vs. -1.04, p < 0.001), skin flaking or peeling (-.55 vs. 0.04, p = 0.053), blistering (-0.82 vs. -0.07, p = 0.033), and pruritus (-2.27 vs. -.67, p = 0.002). There was a return to baseline in all patient-reported breast domains by 3 months (p >0.05) in both arms. CONCLUSION Ultra-hypofractionated whole breast irradiation, consisting of 25 Gy in 5 fractions, provided comparable provider assessed toxicity and cosmetic outcomes to 40 Gy in 15 fractions. At the EOT assessment, ultra-hypofractionation had a better patient reported toxicity profile. Our findings provide further evidence to support daily ultra-hypofractionated whole breast radiotherapy as an appropriate treatment option for early-stage breast cancer.
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Affiliation(s)
- B S Laughlin
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - K S Corbin
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - C S Thorpe
- Department of Radiation Oncology, Sanford Health, Fargo, ND
| | - D A S Toesca
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - M A Golafshar
- Department of Qualitative Health Sciences, Section of Biostatistics, Mayo Clinic, Scottsdale, AZ
| | - L A McGee
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - M Halyard
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - R W Mutter
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S R Keole
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D Shumway
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - L A Vallow
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL
| | - T Z Vern-Gross
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - W W Wong
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - T A DeWees
- Department of Qualitative Health Sciences, Section of Biostatistics, Mayo Clinic, Scottsdale, AZ
| | - C E Vargas
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
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Lucido J, Mullikin TC, Kowalchuk RO, Rose PS, Siontis BL, Morris JM, Johnson-Tesch B, Thull JC, Brinkmann DH, Phillips R, Laack Ii NN, Park SS, Brown PD, Owen D, Merrell KW. Local Control after Re-Irradiation of Spinal Metastases with Stereotactic Body Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e132. [PMID: 37784695 DOI: 10.1016/j.ijrobp.2023.06.933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Determine local control (LC) rate and risk of vertebral compression fractures (VCFs) and radiation myelitis (RM) for patients receiving re-irradiation of spinal metastases (SMs) using stereotactic body radiation therapy (SBRT) from large single-institutional experience with long follow-up. MATERIALS/METHODS Retrospectively identified patients receiving re-irradiation SBRT (rSBRT, 1, 3, or 5 fractions) to SMs previously treated with radiation therapy (RT) and having follow up imaging to assess local control. 1 fraction patients typically received 20-24 Gy and 16-18 Gy to the high- and low-risk planning target volumes (PTVs), respectively, and 27-39 Gy and 21-24 Gy for the 3 fraction patients, with a single level of 50 Gy for 5 fractions. Patient and treatment characteristics for previous RT (pRT) and rSBRT were collected, including histology and dose-volume histogram statistics (DVH). Kaplan-Meier estimates of overall survival (OS), and cumulative incidence (competing with death) of local failure with death as a competing risk was computed for the whole cohort and stratified by radioresistance of histology, and risk of VCF for RM (for treatments at L1 and above) and 95% confidence intervals. Equivalent dose in 2 Gy fractions (EQD2) for PTV and spinal cord (SC) DVH statistics was computed for each individual course and cumulatively, using a/b = 10 Gy for tumor and 2 Gy for SC. RESULTS Identified 107 lesions in 91 patients. 48 (45%) had radioresistant histologies. For all patients, at 1 and 2 years, respectively OS was 64% (55-74%) and 43% (34-55%), LC was 88% (81-94%) and 85% (78-91%) with median follow-up of 52 months (Table 1). OS and LC were not significantly different between radiosensitivity groups (p>0.05). Risk of VCF at 1 and 2 years was 7% (3-13%) and 9% (4-16%). RM was identified in 1 patient, who received 30 Gy in 5 fractions to T1, and had 1-fraction rSBRT 21 months later. SC Dmax was 31.5 Gy for pRT and 10.4 Gy, for rSBRT, resulting in total SC EQD2 of 73 Gy. RM was confirmed on MRI 8 months after rSBRT. Cumulative RM risk at 8 months after rSBRT was estimated at 1% (0-4%). Median EQD2 for the minimum dose to the high and low risk PTVs were 17.7 Gy (interquartile range, IQR, 13.0-27.6 Gy) and 13.7 Gy (IQR, 10.8-19.3 Gy) for rSBRT, and maximum EQD to SC for previous RT, rSBRT, and cumulatively was 38 Gy (IQR, 30-41 Gy), 27 Gy (IQR, 22-36 Gy), and 65 Gy (IQR, 54-73 Gy).Re-irradiation of spinal metastasis with SBRT can be delivered safely and provide high rates of local control, including for radioresistant tumors, as demonstrated with the longest reported follow-up in this setting. CONCLUSION Re-irradiation of SM with SBRT provides high rates of LC even for radioresistant tumors, and low risk of VCF and RM, based on the longest reported follow-up in this setting.
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Affiliation(s)
| | - T C Mullikin
- Department of Radiation Oncology, Duke University, Rochester, MN
| | - R O Kowalchuk
- University of Virginia / Riverside Radiosurgery Center, Newport News, VA
| | - P S Rose
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN
| | - B L Siontis
- Division of Medical Oncology, Mayo Clinic, Rochester, MN
| | - J M Morris
- Department of Radiology, Mayo Clinic, Rochester, MN
| | | | - J C Thull
- Mayo Clinic, Department of Radiation Oncology, Rochester, MN
| | - D H Brinkmann
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - R Phillips
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - N N Laack Ii
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - P D Brown
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D Owen
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - K W Merrell
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
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5
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Kowalchuk RO, Mullikin TC, Spears GM, Rose PS, Siontis BL, Kim DK, Costello BA, Morris JM, Gao RW, Shiraishi S, Lucido J, Olivier K, Owen D, Stish BJ, Waddle MR, Laack Ii NN, Park SS, Brown PD, Merrell KW. Assessment of Minimum Dose as a Strong Predictor of Local Failure after Spine SBRT. Int J Radiat Oncol Biol Phys 2023; 117:e120-e121. [PMID: 37784669 DOI: 10.1016/j.ijrobp.2023.06.909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiation therapy (SBRT) has demonstrated robust clinical benefits in carefully selected patients, improving local control and even overall survival (OS). Even so, a wide range of dose-fractionation schemes are used in clinical practice. We seek to assess a large database to determine clinical and dosimetric predictors of local failure after spine SBRT. MATERIALS/METHODS From a large institutional database, spine SBRT treatments with subsequent imaging follow-up to assess local control were identified. Patients were treated with a simultaneous integrated boost technique using 1 or 3 fractions, generally delivering 20-24 Gy in 1 fraction to the high dose volume and 16 Gy to the low dose volume (or 30-36 Gy and 24 Gy for 3 fraction treatments). Exclusions included: lack of imaging follow-up, proton therapy, and benign primary histologies. Statistical analyses included Cox proportional hazards analyses and the robust log-rank statistic for cut-point analysis. The cumulative incidence of local failure with death as a competing risk was considered as the primary endpoint. RESULTS A total of 522 eligible spine SBRT treatments (68% single fraction) were identified in 377 unique patients. Patients had a median OS of 43.7 months (95% confidence interval: 34.3-54.4). The cumulative incidence of local failure was 19.3% (15.3-23.2) at 1 year and 25.6% (21.1-29.9) at 2 years. Univariate analysis identified that the minimum dose (normalized for the prescription dose) was a strong predictor of local failure (p = 0.0093). Among patients treated with a single fraction, statistical significance was maintained (p = 0.024). No other dosimetric factors were predictive of local failure. In a cut point analysis, the log-rank statistic was maximized at 15.8 Gy minimum dose for single-fraction treatment (HR = 0.51, 95% CI: 0.34 - 0.75, p = 0.0009). Cumulative incidence of local failure was 15.1% (9.8-20.2) vs. 24.7% (17.2-31.5) at 1 year using this cut-off. Comparable local control was demonstrated with a minimum dose of 14 Gy (HR = 0.57, 95%: 0.37 - 0.87, p = 0.009), with reduced local control with lower minimum doses. Among a range of clinical factors assessed, only epidural and soft tissue involvement were predictive of local failure (HR = 1.80 and 1.98, respectively). Multivariable analyses incorporating soft tissue involvement, epidural extension, and multilevel disease confirmed the 15.8 Gy cutoff for single fraction cases (HR = 0.58, 95% CI: 0.38-0.88, p = 0.011). CONCLUSION Spine SBRT offers favorable local control using a range of dose-fractionation schemes; however, minimum dose has a strong association with local control, unlike any other dosimetric factors tested. Furthermore, statistical significance was maintained even when considering epidural extension and potential limitations from dose to the spinal cord. Our data suggests that the minimum dose should be prioritized during treatment planning, ideally to at least 14 - 15.8 Gy for single fraction.
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Affiliation(s)
- R O Kowalchuk
- University of Virginia / Riverside Radiosurgery Center, Newport News, VA
| | - T C Mullikin
- Department of Radiation Oncology, Duke University, Rochester, MN
| | - G M Spears
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - P S Rose
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN
| | - B L Siontis
- Division of Medical Oncology, Mayo Clinic, Rochester, MN
| | - D K Kim
- Department of Radiology, Mayo Clinic, Rochester, MN
| | - B A Costello
- Division of Medical Oncology, Mayo Clinic, Rochester, MN
| | - J M Morris
- Department of Radiology, Mayo Clinic, Rochester, MN
| | - R W Gao
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S Shiraishi
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - J Lucido
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - K Olivier
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D Owen
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - B J Stish
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - M R Waddle
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - N N Laack Ii
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - P D Brown
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - K W Merrell
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
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Horjeti E, Kim Y, Arafa A, Sutera P, Phillips R, Song D, Kiess AP, Tran PT, Park SS, Lucien-Matteoni F. PSMA-Positive Extracellular Vesicles Predict Disease Recurrence in Oligometastatic Castration-Sensitive Prostate Cancer Treated with Stereotactic Ablative Radiotherapy: Analysis of the ORIOLE trial. Int J Radiat Oncol Biol Phys 2023; 117:S36. [PMID: 37784483 DOI: 10.1016/j.ijrobp.2023.06.303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic ablative radiation therapy (SABR) can prolong progression free survival in oligometastatic prostate cancer (omPC) patients. However, predictive tools to identify those who will benefit from SABR are necessary. Our group was the first to demonstrate that plasma levels of prostate cancer-derived extracellular vesicles (ProstEVs) correlate with tumor burden and predict disease progression in omPC after SABR. Herein, we conducted a blinded validation study using plasma samples from the ORIOLE randomized phase 2 clinical trial in castration-sensitive patients. MATERIALS/METHODS Plasma samples from 46 omPC patients from the Baltimore ORIOLE trial: a 2:1 ratio randomization to SABR vs observation (NCT02680587). Baseline PSMA+ ProstEV levels were measured by standardized and calibrated nanoscale flow cytometry using fluorescent PSMA antibodies. Median ProstEV levels was used as cut-off for low and high levels. Kaplan-Meier curves and Cox regression models were used to determine the association of ProstEV levels with clinical outcomes [PSA progression-free survival (psaPFS) and radiographic distant progression free survival (rPFS)]. RESULTS No association was observed between number of metastatic lesions or baseline PSA and plasma ProstEV levels. The rPFS for patients treated with SABR was 29.6 months. The rPFS for patients treated with SABR with high and low ProstEV levels were 11.1 months and 36 months, respectively (Hazard Ratio: 2.85; 95% CI, 1.01-7.48; P = 0.02). The psaPFS for patients treated with SABR was 11.9 months. The psaPFS for patients with high and low ProstEV levels were 5.9 months and 24.3 months, respectively (HR: 2.44; 95% CI, 1.00-5.94; P = 0.03). CONCLUSION ProstEVs is the first blood biomarker of tumor burden that can prognosticate the risk of disease recurrence in omPC patients treated with SABR. While biomarker-guided trials are warranted, our validation study strengthens the clinical value of ProstEVs for personalized radiation therapy.
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Affiliation(s)
- E Horjeti
- Department of Urology, Mayo Clinic, Rochester, MN
| | - Y Kim
- Department of Urology, Mayo Clinic, Rochester, MN
| | - A Arafa
- University of Minnesota, Minneapolis, MN
| | - P Sutera
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medicine, Baltimore, MD
| | - R Phillips
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D Song
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD
| | - A P Kiess
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD
| | - P T Tran
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - F Lucien-Matteoni
- Department of Urology, Mayo Clinic, Rochester, MN; Department of Immunology, Mayo Clinic, Rochester, MN
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7
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Ebner DK, Evans JM, Christensen B, Breinholt J, Gamez ME, Lester SC, Routman DM, Ma DJ, Price K, Dong H, Park SS, Chintakuntlawar AV, Neben-Wittich MA, McGee LA, Garces Y, Patel SH, Foote RL, Evans JD. Unique T-cell Sub-Population Shifts after SBPT and Nivolumab in Platinum Refractory HNC: Biomarker Correlates from ROR1771. Int J Radiat Oncol Biol Phys 2023; 117:e580. [PMID: 37785763 DOI: 10.1016/j.ijrobp.2023.06.1920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) ROR1771 was a clinical trial investigating the use of stereotactic body proton radiotherapy (SBPT) and nivolumab in recurrent platinum refractory head and neck squamous cell carcinoma (HNSCC). The planned analysis of T-cell subpopulation and biomarker response is herein presented. MATERIALS/METHODS Patients with metastatic histologically confirmed HNSCC from any primary site received 2 cycles of nivolumab followed by SBPT to 1-2 selected target lesion(s) (hilar/lung: 8 of 12 patients), followed by maintenance nivolumab. Peripheral blood mononuclear cells were isolated pre-/post-treatment. Flow cytometry identified T-cell subpopulations. Single Cell 5' Gene Expression (GEX) and V(D)J T Cell Receptor libraries were prepared using Single Cell Immune Profiling. Seurat (v4.1.1) was used to identify cell type clusters, and differential expression post-filtration was evaluated using the Wilcoxon Rank Sum test. RESULTS A total of 12 patients were eligible for analysis, with one alive at time of analysis, 52 months from start of treatment. Median overall survival here was 12.5 months vs. 7.5-months on CheckMate 141. SBPT ranged from 35-50 Gy. Sequential changes in T-cell populations from baseline were noted with initiation of nivolumab, driving decrease in tumor-reactive (TTR; CD11ahighPD1+CD8+), central memory (TCM; CCR7+CD45RA-), and effector T-cells (TEF; CCR7-CD45RA-). TTR and TCM increased following SBPT, with greatest increase (3.5x TTR and 5.2x TCM) in the surviving patient. An average of 68 genes with significant differential expression between timepoints (p<0.0001) demonstrated RNA gene expression changes across all cell subtypes, including ribosomal (RPL and RPS) genes, ACTB, FTL, MALAT1, and others. This averaged 113 genes across all timepoints in the surviving patient, with peak following nivolumab induction. On T-cell receptor (TCR) analysis of this patient, the predominant clonotype diversity changed substantially following nivolumab. Following SBPT, clonotype diversity again changed to include a milieu seen neither at baseline nor with nivolumab alone. These TCRs persisted for approximately 2 weeks following SBPT before returning to resemble the nivolumab-induced TCR diversity alone, coinciding with disease recurrence. CONCLUSION ROR1771 demonstrated overall survival favorably comparable to CheckMate 141. Biomarker analysis of peripheral blood samples demonstrated significant shifts in T-cell subpopulations and underlying gene expression to nivolumab and then to SBPT administration. SBPT to a target lesion changed TCR clonotypes within the peripheral blood beyond those seen with nivolumab administration, with fading of these TCR clonotypes coinciding with recurrence. SBPT in combination with nivolumab may drive systemic immunologic change above that induced by nivolumab alone and warrants further investigation.
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Affiliation(s)
- D K Ebner
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - J M Evans
- Intermountain Precision Genomics, St George, UT
| | | | - J Breinholt
- Intermountain Precision Genomics, St George, UT
| | - M E Gamez
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S C Lester
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D M Routman
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - D J Ma
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - K Price
- Department of Medical Oncology, Mayo Clinic, Rochester, MN
| | - H Dong
- Department of Urology and Immunology, Mayo Clinic, Rochester, MN
| | - S S Park
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | | | | | - L A McGee
- Department of Radiation Oncology, Mayo Clinic, Phoenix, AZ
| | - Y Garces
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - S H Patel
- Department of Radiation Oncology, Mayo Clinic Arizona, Phoenix, AZ
| | - R L Foote
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN
| | - J D Evans
- Department of Radiation Oncology, Intermountain Healthcare, Murray, UT
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8
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Park SS, Gonzalez-Juarbe N, Riegler AN, Im H, Hale Y, Platt MP, Croney C, Briles DE, Orihuela CJ. Streptococcus pneumoniae binds to host GAPDH on dying lung epithelial cells worsening secondary infection following influenza. Cell Rep 2021; 35:109267. [PMID: 34133917 PMCID: PMC8265312 DOI: 10.1016/j.celrep.2021.109267] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 04/07/2021] [Accepted: 05/26/2021] [Indexed: 12/13/2022] Open
Abstract
Streptococcus pneumoniae (Spn) alone and during co-infection with influenza A virus (IAV) can result in severe pneumonia with mortality. Pneumococcal surface protein A (PspA) is an established virulence factor required for Spn evasion of lactoferricin and C-reactive protein-activated complement-mediated killing. Herein, we show that PspA functions as an adhesin to dying host cells. We demonstrate that PspA binds to host-derived glyceraldehyde-3-phosphate dehydrogenase (GAPDH) bound to outward-flipped phosphatidylserine residues on dying host cells. PspA-mediated adhesion was to apoptotic, pyroptotic, and necroptotic cells, but not healthy lung cells. Using isogenic mutants of Spn, we show that PspA-GAPDH-mediated binding to lung cells increases pneumococcal localization in the lower airway, and this is enhanced as a result of pneumolysin exposure or co-infection with IAV. PspA-mediated binding to GAPDH requires amino acids 230-281 in its α-helical domain with intratracheal inoculation of this PspA fragment alongside the bacteria reducing disease severity in an IAV/Spn pneumonia model.
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Affiliation(s)
- Sang-Sang Park
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Ashleigh N Riegler
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hansol Im
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yvette Hale
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Maryann P Platt
- Infectious Diseases and Genomic Medicine Group, J. Craig Venter Institute, Rockville, MD, USA
| | - Christina Croney
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - David E Briles
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Carlos J Orihuela
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA.
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9
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Park SS, Gonzalez-Juarbe N, Martínez E, Hale JY, Lin YH, Huffines JT, Kruckow KL, Briles DE, Orihuela CJ. Streptococcus pneumoniae Binds to Host Lactate Dehydrogenase via PspA and PspC To Enhance Virulence. mBio 2021; 12:e00673-21. [PMID: 33947761 PMCID: PMC8437407 DOI: 10.1128/mbio.00673-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 02/06/2023] Open
Abstract
Pneumococcal surface protein A (PspA) and pneumococcal surface protein C (PspC, also called CbpA) are major virulence factors of Streptococcus pneumoniae (Spn). These surface-exposed choline-binding proteins (CBPs) function independently to inhibit opsonization, neutralize antimicrobial factors, or serve as adhesins. PspA and PspC both carry a proline-rich domain (PRD) whose role, other than serving as a flexible connector between the N-terminal and C-terminal domains, was up to this point unknown. Herein, we demonstrate that PspA binds to lactate dehydrogenase (LDH) released from dying host cells during infection. Using recombinant versions of PspA and isogenic mutants lacking PspA or specific domains of PspA, this property was mapped to a conserved 22-amino-acid nonproline block (NPB) found within the PRD of most PspAs and PspCs. The NPB of PspA had specific affinity for LDH-A, which converts pyruvate to lactate. In a mouse model of pneumonia, preincubation of Spn carrying NPB-bearing PspA with LDH-A resulted in increased bacterial titers in the lungs. In contrast, incubation of Spn carrying a version of PspA lacking the NPB with LDH-A or incubation of wild-type Spn with enzymatically inactive LDH-A did not enhance virulence. Preincubation of NPB-bearing Spn with lactate alone enhanced virulence in a pneumonia model, indicating exogenous lactate production by Spn-bound LDH-A had an important role in pneumococcal pathogenesis. Our observations show that lung LDH, released during the infection, is an important binding target for Spn via PspA/PspC and that pneumococci utilize LDH-A derived lactate for their benefit in vivoIMPORTANCEStreptococcus pneumoniae (Spn) is the leading cause of community-acquired pneumonia. PspA and PspC are among its most important virulence factors, and these surface proteins carry the proline-rich domain (PRD), whose role was unknown until now. Herein, we show that a conserved 22-amino-acid nonproline block (NPB) found within most versions of the PRD binds to host-derived lactate dehydrogenase A (LDH-A), a metabolic enzyme which converts pyruvate to lactate. PspA-mediated binding of LDH-A increased Spn titers in the lungs and this required LDH-A enzymatic activity. Enhanced virulence was also observed when Spn was preincubated with lactate, suggesting LDH-A-derived lactate is a vital food source. Our findings define a role for the NPB of the PRD and show that Spn co-opts host enzymes for its benefit. They advance our understanding of pneumococcal pathogenesis and have key implications on the susceptibility of individuals with preexisting airway damage that results in LDH-A release.
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Affiliation(s)
- Sang-Sang Park
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Norberto Gonzalez-Juarbe
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, USA
| | - Eriel Martínez
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Joanetha Yvette Hale
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yi-Han Lin
- Infectious Diseases and Genomic Medicine Group, J Craig Venter Institute, Rockville, Maryland, USA
| | - Joshua T Huffines
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Katherine L Kruckow
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - David E Briles
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Carlos J Orihuela
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
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10
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Park SS, Lee S, Rhee DK. Crystal Structure of the Pneumococcal Vancomycin-Resistance Response Regulator DNA-Binding Domain. Mol Cells 2021; 44:179-185. [PMID: 33795535 PMCID: PMC8019601 DOI: 10.14348/molcells.2021.2235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/10/2021] [Accepted: 02/25/2021] [Indexed: 11/27/2022] Open
Abstract
Vancomycin response regulator (VncR) is a pneumococcal response regulator of the VncRS two-component signal transduction system (TCS) of Streptococcus pneumoniae. VncRS regulates bacterial autolysis and vancomycin resistance. VncR contains two different functional domains, the N-terminal receiver domain and C-terminal effector domain. Here, we investigated VncR C-terminal DNA binding domain (VncRc) structure using a crystallization approach. Crystallization was performed using the micro-batch method. The crystals diffracted to a 1.964 Å resolution and belonged to space group P212121. The crystal unit-cell parameters were a = 25.71 Å, b = 52.97 Å, and c = 60.61 Å. The structure of VncRc had a helix-turn-helix motif highly similar to the response regulator PhoB of Escherichia coli. In isothermal titration calorimetry and size exclusion chromatography results, VncR formed a complex with VncS, a sensor histidine kinase of pneumococcal TCS. Determination of VncR structure will provide insight into the mechanism by how VncR binds to target genes.
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Affiliation(s)
- Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Korea
| | - Sangho Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Korea
| | - Dong-Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Suwon 16419, Korea
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11
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Affiliation(s)
- S S Park
- Division of Intensive Care Medicine, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates; Division of Intensive Care Medicine, Seoul National University Hospital, Seoul, Republic of Korea
| | - H Y Oh
- Division of Internal Medicine, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates
| | - D J Hong
- Department of Laboratory Medicine, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates; Department of Laboratory Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
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12
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Ghosh P, Shah M, Ravichandran S, Park SS, Iqbal H, Choi S, Kim KK, Rhee DK. Pneumococcal VncR Strain-Specifically Regulates Capsule Polysaccharide Synthesis. Front Microbiol 2019; 10:2279. [PMID: 31632380 PMCID: PMC6781885 DOI: 10.3389/fmicb.2019.02279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 09/18/2019] [Indexed: 11/19/2022] Open
Abstract
Capsular polysaccharides (CPS), a major virulence factor in Streptococcus pneumoniae, become thicker during blood invasion while not during asymptomatic nasopharyngeal colonization. However, the underlying mechanism controlling this differential pneumococcal CPS regulation remain unclear. Here, we show how VncR, the response regulator of the vancomycin resistance locus (vncRS operon), regulates CPS expression in vncR mutants in three serotype (type 2, 3, and 6B) backgrounds upon exposure to serum lactoferrin (LF). Comparative analysis of CPS levels in the wild type (WT) of three strains and their isogenic vncR mutants after LF exposure revealed a strain-specific alteration in CPS production. Consistently, VncR-mediated strain-specific CPS production is correlated with pneumococcal virulence, in vivo. Electrophoretic mobility-shift assay and co-immunoprecipitation revealed an interaction between VncR and the cps promoter (cpsp) in the presence of serum. In addition, in silico analysis uncovered this protein-DNA interaction, suggesting that VncR binds with the cpsp, and recognizes the strain-specific significance of the tandem repeats in cpsp. Taken together, the interaction of VncR and cpsp after serum exposure plays an essential role in regulating differential strain-specific CPS production, which subsequently determines strain-specific systemic virulence. This study highlights how host protein LF contributes to pneumococcal VncR-mediated CPS production. As CPS plays a significant role in immune evasion, these findings suggest that drugs designed to interrupt the VncR-mediated CPS production could help to combat pneumococcal infections.
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Affiliation(s)
| | - Masaud Shah
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Subramaniyam Ravichandran
- Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, Suwon, South Korea
| | - Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Hamid Iqbal
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Sangdun Choi
- Department of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Kyeong Kyu Kim
- Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, Suwon, South Korea
| | - Dong Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
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13
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Wiemers EE, Park SS, Seltzer JA, Sohn H. CHANGES IN FINANCIAL AND TIME TRANSFERS WITH PARENTS OVER 25 YEARS: EVIDENCE FROM THE 1988 AND 2013 PSID. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- E E Wiemers
- University of Massachusetts Boston, Boston, Massachusetts, United States
| | - S S Park
- University of California, Department of Sociology, Los Angeles, CA, USA
| | - J A Seltzer
- University of California, Department of Sociology, Los Angeles, CA, USA
| | - H Sohn
- University of California, California Center for Population Research, Los Angeles, CA, USA
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14
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Mukerji R, Hendrickson C, Genschmer KR, Park SS, Bouchet V, Goldstein R, Lefkowitz EJ, Briles DE. The diversity of the proline-rich domain of pneumococcal surface protein A (PspA): Potential relevance to a broad-spectrum vaccine. Vaccine 2018; 36:6834-6843. [PMID: 30293761 DOI: 10.1016/j.vaccine.2018.08.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/18/2018] [Accepted: 08/19/2018] [Indexed: 01/28/2023]
Abstract
Pneumococcal surface protein A (PspA) is a surface exposed, highly immunogenic protein of Streptococcus pneumoniae. Its N-terminal α-helical domain (αHD) elicits protective antibody in humans and animals that can protect mice from fatal infections with pneumococci and can be detected in vitro with opsonophagocytosis assays. The proline-rich domain (PRD) in the center of the PspA sequence can also elicit protection. This study revealed that although the sequence of PRD was diverse, PRD from different pneumococcal isolates contained many shared elements. The inferred amino acid sequences of 123 such PRDs, which were analyzed by assembly and alignment-free (AAF) approaches, formed three PRD groups. Of these sequences, 45 were classified as Group 1, 19 were classified as Group 2, and 59 were classified as Group 3. All Group 3 sequences contained a highly conserved 22-amino acid non-proline block (NPB). A significant polymorphism was observed, however, at a single amino acid position within NPB. Each of the three PRD groups had characteristic patterns of short amino acid repeats, with most of the repeats being found in more than one PRD group. One of these repeats, PKPEQP as well as the NPB were previously shown to elicit protective antibodies in mice. In this study, we found that sera from 12 healthy human adult volunteers contained antibodies to all three PRD groups. This suggested that a PspA-containing vaccine containing carefully selected PRDs and αHDs could redundantly cover the known diversity of PspA. Such an approach might reduce the chances of PspA variants escaping a PspA vaccine's immunity.
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Affiliation(s)
- Reshmi Mukerji
- Department of Microbiology, University of Alabama at Birmingham, United States
| | - Curtis Hendrickson
- Center for Clinical and Translational Sciences, University of Alabama at Birmingham, United States
| | - Kristopher R Genschmer
- Department of Microbiology, University of Alabama at Birmingham, United States; Department of Medicine, Division of Pulmonary, Allergy and Critical Care, United States
| | - Sang-Sang Park
- Department of Microbiology, University of Alabama at Birmingham, United States
| | - Valérie Bouchet
- Section of Molecular Genetics, Maxwell Finland Laboratory for Infectious Diseases, Division of Pediatric Infectious Diseases, Boston University Medical Center, Boston, MA 02118, United States
| | - Richard Goldstein
- Section of Molecular Genetics, Maxwell Finland Laboratory for Infectious Diseases, Division of Pediatric Infectious Diseases, Boston University Medical Center, Boston, MA 02118, United States
| | - Elliot J Lefkowitz
- Department of Microbiology, University of Alabama at Birmingham, United States; Center for Clinical and Translational Sciences, University of Alabama at Birmingham, United States
| | - David E Briles
- Department of Microbiology, University of Alabama at Birmingham, United States.
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15
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Lee S, Ghosh P, Kwon H, Park SS, Kim GL, Choi SY, Kim EH, Tran TDH, Seon SH, Le NT, Iqbal H, Lee S, Pyo S, Rhee DK. Induction of the pneumococcal vncRS operon by lactoferrin is essential for pneumonia. Virulence 2018; 9:1562-1575. [PMID: 30246592 PMCID: PMC6177237 DOI: 10.1080/21505594.2018.1526529] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/12/2018] [Indexed: 12/29/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus), the major pathogen for pneumonia, commonly colonizes the lung, but the mechanism underlying the coordination of virulence factors during invasion via the host protein remains poorly understood. Bacterial lysis releases the components of the cell wall, and triggers innate immunity and the subsequent secretion of pro-inflammatory cytokines. Previously, the virulence of the pep27 mutant was shown to be attenuated as a feasible candidate for vaccine development. However, the role of pep27 gene, belonging to the vancomycin-resistance locus (vncRS operon), in virulence, is largely unknown. This study demonstrates that transferrin in the host serum reduces the survival of the host during S. pneumoniae infections in mice. The exposure of the pneumococcal D39 strain to lactoferrin induced the vncRS operon, lysis, and subsequent in vivo cytokine production, resulting in lung inflammation. However, these responses were significantly attenuated in pneumococci harboring a mutation in pep27. Mechanistically, the VncS ligand, identified as lactoferrin, induced the vncRS operon and increased the in vivo mortality rates. Thus, serum-induced activation of vncRS plays an essential role in inducing pneumonia.
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Affiliation(s)
- Seungyeop Lee
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | | | - Hyogyoung Kwon
- Soonchunhyang Institute of Medi-bio Science, Soonchunhyang University, Cheonan, Korea
| | - Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Gyu-Lee Kim
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Sang-Yoon Choi
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Eun-Hye Kim
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | | | - Seung Han Seon
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Nhat Tu Le
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Hamid Iqbal
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Sangho Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Korea
| | - Suhkneung Pyo
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Dong-Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
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16
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Kim GL, Luong TT, Park SS, Lee S, Ha JA, Nguyen CT, Ahn JH, Park KT, Paik MJ, Suhkneung-Pyo, Briles DE, Rhee DK. Inhibition of Autolysis by Lipase LipA in Streptococcus pneumoniae Sepsis. Mol Cells 2017; 40:935-944. [PMID: 29281779 PMCID: PMC5750712 DOI: 10.14348/molcells.2017.0201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/19/2017] [Accepted: 11/21/2017] [Indexed: 02/06/2023] Open
Abstract
More than 50% of sepsis cases are associated with pneumonia. Sepsis is caused by infiltration of bacteria into the blood via inflammation, which is triggered by the release of cell wall components following lysis. However, the regulatory mechanism of lysis during infection is not well defined. Mice were infected with Streptococcus pneumoniae D39 wild-type (WT) and lipase mutant (ΔlipA) intranasally (pneumonia model) or intraperitoneally (sepsis model), and survival rate and pneumococcal colonization were determined. LipA and autolysin (LytA) levels were determined by qPCR and western blotting. S. pneumoniae Spd_1447 in the D39 (type 2) strain was identified as a lipase (LipA). In the sepsis model, but not in the pneumonia model, mice infected with the ΔlipA displayed higher mortality rates than did the D39 WT-infected mice. Treatment of pneumococci with serum induced LipA expression at both the mRNA and protein levels. In the presence of serum, the ΔlipA displayed faster lysis rates and higher LytA expression than the WT, both in vitro and in vivo. These results indicate that a pneumococcal lipase (LipA) represses autolysis via inhibition of LytA in a sepsis model.
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Affiliation(s)
- Gyu-Lee Kim
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | | | - Sang-Sang Park
- Department of Microbiology, University of Alabama at Birmingham, AL 35294-2170,
USA
| | - Seungyeop Lee
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | - Jung Ah Ha
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | | | - Ji Hye Ahn
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | - Ki-Tae Park
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | - Man-Jeong Paik
- College of Pharmacy, Sunchon National University, Suncheon 57922,
Korea
| | - Suhkneung-Pyo
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
| | - David E. Briles
- Department of Microbiology, University of Alabama at Birmingham, AL 35294-2170,
USA
| | - Dong-Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Suwon 16419,
Korea
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17
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Park SS. Laudation on Prof. Alexander Berghaus. HNO 2017; 66:120-121. [PMID: 29230509 DOI: 10.1007/s00106-017-0451-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S S Park
- Department of Otolaryngology-Head & Neck Surgery, University of Virginia, Box 800713, 22908-0713, Charlottesville, USA.
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18
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Kang IG, Jeong WJ, Park CS, Ryu HS, Lee MJ, Park SS, Kim HJ. Hydrothorax Due to Extravasation of Intravenous Contrast after Power Injection through Right Subclavian Catheter. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791101800111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We report a case of hydrothorax after receiving intravenous (IV) contrast material by power injector through right subclavian central venous catheter (CVC) line. A 38-year-old woman presented to the local emergency department with hypotension after a pedestrian accident. After resuscitation, CVC was inserted into her right subclavian vein and fluid was administered well before computed tomography (CT) enhancement. Contrast-enhanced CT scan showed a large amount of extravasation of contrast material and fluid collection in the thoracic and pericardial cavities which was not shown in non-enhanced CT scan. During operation, vascular perforation was found in right subclavian vein. This case highlights that emergency physicians must keep in mind the possibility of vessel injury after CVC insertion and contrast material is preferably injected via peripheral IV access.
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Park CS, Kang IG, Heo SJ, Chae YS, Kim HJ, Park SS, Lee MJ, Jeong WJ. A Randomised, Cross over Study Using a Mannequin Model to Evaluate the Effects on CPR Quality of Real-Time Audio-Visual Feedback Provided by a Smartphone Application. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791402100304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objective To evaluate the effect of real time feedback provided by smartphone application on cardiopulmonary resuscitation (CPR) performance. Methods Participants were randomised in two groups based on whether chest compression with or without the assistance of the smartphone application. Both groups performed hands-only CPR on a mannequin for 4 minutes. Data on CPR performance of both groups was compared. To assess the reliability the feedback value, we compared the CPR data from Skillmeter and data from smartphone. A questionnaire survey to participants about the usefulness of the application was also evaluated. Results Twenty-one subjects were recruited for the study. We found no significant difference in mean chest compression rate (103.3±5.0/min vs. 107.1±1.7/min; p=0.133) and depth between the two groups (47.3 [39.3, 56.2] mm vs. 45.8 [40.3, 49.9] mm; p=0.085). The proportion of adequate compression depth over the total compression was significantly higher in the group using the smartphone (38.1% vs. 22.2%; p=0.034). The CPR data displayed on smartphone application in mannequin's chest was not different from Skillmeter software. The majority of the participants considered the application easy to use, but holding the smartphone during CPR hampered compression. Conclusions Real-time audio-visual feedback on CPR depth and rate using a smartphone application can help to maintain the adequate chest compression depth in prolonged CPR. A better method to hold the smartphone may maximise the feedback effect on CPR quality. (Hong Kong j.emerg.med. 2014;21:153-160)
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Affiliation(s)
- CS Park
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - IG Kang
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - SJ Heo
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - YS Chae
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - HJ Kim
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - SS Park
- Konyang University Hospital, Department of Emergency Medicine, Republic of Korea
| | - MJ Lee
- Kyungpook National University Hospital, Department of Emergency Medicine, Republic of Korea
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20
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Park DW, Kim SH, Moon JY, Song JS, Choi J, Kwak HJ, Jeong MG, Ro YS, Kim TH, Sohn JW, Shin DH, Park SS, Yoon HJ. The effect of low-volatile organic compounds, water-based paint on aggravation of allergic disease in schoolchildren. Indoor Air 2017; 27:320-328. [PMID: 27007057 DOI: 10.1111/ina.12301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 03/19/2016] [Indexed: 06/05/2023]
Abstract
Whether indoor painting aggravates preexisting allergic diseases remains unclear. We aimed to evaluate the impact of new classroom painting on aggravation of asthma, allergic rhinitis (AR), and atopic dermatitis (AD) in children. Studied school was previously painted with conventional water-based paint 20 years ago and had natural ventilation system. We identified a total of 172 children aged 10-12 years with allergic diseases in 17 classrooms, which were allocated to newly painted rooms with low-volatile organic compounds (VOC), water-based paint, or existing rooms. After painting, there was no intervention or internal airflow to influence indoor air environment in both classrooms. We prospectively assessed the symptom severity and serious events of allergic diseases between both classrooms at baseline and after one and eight weeks after painting. At one and eight weeks, there were no significant changes in the Childhood Asthma Control Test scores, the fractional nitric oxide levels, lung function in asthmatic children in either classroom. There were also no significant changes in the severity score of AR or AD, or serious events in all allergic diseases. These findings suggest classroom painting with this new paint at the levels encountered in this study might not be a major aggravating factor for school-aged children with allergic diseases.
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Affiliation(s)
- D W Park
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - S-H Kim
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - J-Y Moon
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - J S Song
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - J Choi
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - H J Kwak
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - M G Jeong
- Department of Dermatology, Hanyang University College of Medicine, Seoul, Korea
| | - Y S Ro
- Department of Dermatology, Hanyang University College of Medicine, Seoul, Korea
| | - T H Kim
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - J W Sohn
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - D H Shin
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - S S Park
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
| | - H J Yoon
- Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
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Mutter RW, Park SS, Hieken TJ, Vargas CE, Mei-Yin PC, Kathryn RJ, Hector VR, Kimberly CS, Elizabeth YS, Daniel VW. Abstract OT2-03-03: A randomized trial of 15 fraction vs 25 fraction pencil beam scanning proton radiotherapy after mastectomy in patients requiring regional nodal irradiation. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-ot2-03-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Post-mastectomy radiotherapy improves survival in women with node-positive breast cancer. Pencil beam scanning proton therapy is attractive due to potential to reduce the dose to the heart and lungs compared with traditional photon techniques while improving conformality and limiting skin dose compared with passively scanned proton therapy. The optimal dose and fractionation for pencil-beam scanning proton therapy remains unknown.
Trial Design: This is a multi-center open label phase II randomized controlled trial to determine the safety of 15 fraction vs 25 fraction pencil beam scanning proton radiotherapy after mastectomy in patients requiring regional nodal irradiation.
Eligibility Criteria: Patients ≥ 18 years with primary, non-inflammatory invasive breast cancer who have undergone mastectomy with or without immediate reconstruction and chest wall and regional nodal irradiation planned.
Aims: To determine whether the 24 month complication rate (defined as grade 3 or greater late adverse events, and unplanned surgical intervention in patients who undergo mastectomy with reconstruction) of 15 fraction chest wall and regional node pencil beam scanning proton radiotherapy is acceptable relative to 25 fraction chest wall and regional nodal pencil beam scanning proton radiotherapy and worthy of further investigation.
Statistical methods: The study is designed as a non-inferiority/superiority “hybrid” design using the approach of Freidlin et al. It is Using a one-sided type I error rate of 0.05 (corresponding equivalently to constructing a 1-sided 95% confidence limit), 72 evaluable patients will have 80% power to reject the null hypothesis that the 24-month complication rate in the experimental arm is higher than that of the control arm by more than 10% (i.e. rule out inferiority) under the alternative hypothesis that the complication rate in the experimental arm is 5% less than that of the control arm (i.e. superiority). However, the design will have only 41% power when the two treatment arms are equivalent (i.e. the complication rate is 10% for both arms).
Accrual: The study opened in June 2016. Five of a planned eighty-two patients have been accrued to date.
Citation Format: Mutter RW, Park SS, Hieken TJ, Vargas CE, Mei-Yin PC, Kathryn RJ, Hector VR, Kimberly CS, Elizabeth YS, Daniel VW. A randomized trial of 15 fraction vs 25 fraction pencil beam scanning proton radiotherapy after mastectomy in patients requiring regional nodal irradiation [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-03-03.
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Kim GL, Choi SY, Seon SH, Lee S, Park SS, Song JY, Briles DE, Rhee DK. Pneumococcal pep27 mutant immunization stimulates cytokine secretion and confers long-term immunity with a wide range of protection, including against non-typeable strains. Vaccine 2016; 34:6481-6492. [DOI: 10.1016/j.vaccine.2016.10.071] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 10/30/2016] [Accepted: 10/31/2016] [Indexed: 12/18/2022]
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Mansfield AS, Aubry MC, Moser JC, Harrington SM, Dronca RS, Park SS, Dong H. Temporal and spatial discordance of programmed cell death-ligand 1 expression and lymphocyte tumor infiltration between paired primary lesions and brain metastases in lung cancer. Ann Oncol 2016; 27:1953-8. [PMID: 27502709 PMCID: PMC5035793 DOI: 10.1093/annonc/mdw289] [Citation(s) in RCA: 254] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 07/18/2016] [Indexed: 12/26/2022] Open
Abstract
The tumor microenvironments of paired primary lung cancers and brain metastases are significantly different, such that many of the metastases lose PD-L1 expression, lymphocyte infiltration or both with greater discrepancies over time. The spatial and temporal heterogeneity of PD-L1 expression may limit its use as a tissue-based predictive biomarker in lung cancer. Background The dynamics of PD-L1 expression may limit its use as a tissue-based predictive biomarker. We sought to expand our understanding of the dynamics of PD-L1 expression and tumor-infiltrating lymphocytes (TILs) in patients with lung cancer-related brain metastases. Experimental design Paired primary lung cancers and brain metastases were identified and assessed for PD-L1 and CD3 expression by immunohistochemistry. Lesions with 5% or greater PD-L1 expression were considered positive. Agreement statistics and the χ2 or Fisher's exact test were used for analysis. Results We analyzed 146 paired lesions from 73 cases. There was disagreement of tumor cell PD-L1 expression in 10 cases (14%, κ = 0.71), and disagreement of TIL PD-L1 expression in 19 cases (26%, κ = 0.38). Most paired lesions with discordant tumor cell expression of PD-L1 were obtained 6 or more months apart. When specimens were categorized using a proposed tumor microenvironment categorization scheme based on PD-L1 expression and TILs, there were significant changes in the classifications because many of the brain metastases lacked either PD-L1 expression, tumor lymphocyte infiltration or both even when they were present in the primary lung cancer specimens (P = 0.009). Conclusions We identified that there are significant differences between the tumor microenvironment of paired primary lung cancers and brain metastases. When physicians decide to treat patients with lung cancer with a PD-1 or PD-L1 inhibitor, they must do so in the context of the spatial and temporal heterogeneity of the tumor microenvironment.
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Affiliation(s)
- A S Mansfield
- Division of Medical Oncology, Departments of Oncology
| | | | | | | | - R S Dronca
- Division of Medical Oncology, Departments of Oncology
| | - S S Park
- Radiation Oncology, Mayo Clinic, Rochester, USA
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24
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Lee JK, Lee J, Park SS, Heo EY, Park YS, Lee CH, Lee SM, Yoon HI, Yim JJ, Yoo CG, Chung HS, Kim YW, Han SK, Kim DK. Effect of inhalers on the development of haemoptysis in patients with non-cystic fibrosis bronchiectasis. Int J Tuberc Lung Dis 2015; 18:363-70. [PMID: 24670577 DOI: 10.5588/ijtld.13.0255] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The association of inhaler use with haemoptysis has rarely been reported in patients with non-cystic fibrosis (CF) bronchiectasis. OBJECTIVE To elucidate the effect of inhaler use on the development of haemoptysis in patients with non-CF bronchiectasis. METHODS In a case-crossover study of 192 non-CF bronchiectasis patients with a history of haemoptysis and inhaler use, the risk of haemoptysis associated with the use of inhalers was elucidated. Two inhaled corticosteroids/long-acting β₂-agonists (ICS/LABA), one long-acting muscarinic antagonist and one short-acting β₂-agonist (SABA) were evaluated. The case and control periods were defined respectively as 030 and 180210 days before haemoptysis. RESULTS The risk of haemoptysis during the case period was 3.51 times higher than during the control period with any use of inhalers (95%CI 1.966.28). The results of clinically significant haemoptysis showed good agreement with those of total events. These associations were consistent with the sensitivity analyses. In the sub-analysis according to inhaler type, ICS/LABA and SABA were significantly associated with an increased risk of haemoptysis (aOR 2.62, 95%CI 1.255.45; aOR 2.51, 95%CI 2.235.15). CONCLUSIONS In patients with non-CF bronchiectasis, the use of inhalers, especially including 2-agonist, was associated with an increased risk of haemoptysis.
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Affiliation(s)
- J-K Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - J Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - S S Park
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Republic of Korea
| | - E Y Heo
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Republic of Korea
| | - Y S Park
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - C H Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - S-M Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - H I Yoon
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam-si, Republic of Korea
| | - J-J Yim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - C-G Yoo
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - H S Chung
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Republic of Korea
| | - Y W Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - S K Han
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - D K Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Republic of Korea
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25
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Nam Y, Jung J, Park SS, Kim SJ, Shin SJ, Choi JH, Kim M, Yoon HE. Disseminated mucormycosis with myocardial involvement in a renal transplant recipient. Transpl Infect Dis 2015; 17:890-6. [PMID: 26538076 DOI: 10.1111/tid.12452] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 08/05/2015] [Accepted: 08/13/2015] [Indexed: 12/20/2022]
Abstract
We report the case of a renal transplant recipient with pulmonary and splenic mucormycosis whose demise was accelerated by a myocardial abscess. Once pulmonary and splenic mucormycosis was diagnosed, liposomal amphotericin B was started and immunosuppressant treatments were discontinued. The pulmonary cavities regressed during treatment, but new myocardial and peri-allograft abscesses developed. The myocardial abscess diffusely infiltrated the left ventricular wall and was associated with akinesia, which led to sudden cardiac arrest. This case demonstrates a rare manifestation of mucormycosis and highlights the fatality and invasiveness of this infection.
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Affiliation(s)
- Y Nam
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea
| | - J Jung
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea
| | - S S Park
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea
| | - S J Kim
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.,Division of Nephrology, Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea
| | - S J Shin
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.,Division of Nephrology, Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea
| | - J H Choi
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.,Division of Infectious Disease, Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea
| | - M Kim
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.,Division of Cardiology, Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea
| | - H E Yoon
- Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.,Division of Nephrology, Department of Internal Medicine, Incheon St. Mary's Hospital, Incheon, Korea
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26
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Nguyen CT, Park SS, Rhee DK. Stress responses in Streptococcus species and their effects on the host. J Microbiol 2015; 53:741-9. [PMID: 26502957 DOI: 10.1007/s12275-015-5432-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 09/30/2015] [Accepted: 09/30/2015] [Indexed: 12/15/2022]
Abstract
Streptococci cause a variety of diseases, such as dental caries, pharyngitis, meningitis, pneumonia, bacteremia, endocarditis, erysipelas, and necrotizing fasciitis. The natural niche of this genus of bacteria ranges from the mouth and nasopharynx to the skin, indicating that the bacteria will inevitably be subjected to environmental changes during invasion into the host, where it is exposed to the host immune system. Thus, the Streptococcus-host interaction determines whether bacteria are cleared by the host's defenses or whether they survive after invasion to cause serious diseases. If this interaction was to be deciphered, it could aid in the development of novel preventive and therapeutic agents. Streptococcus species possess many virulent factors, such as peroxidases and heat-shock proteins (HSPs), which play key roles in protecting the bacteria from hostile host environments. This review will discuss insights into the mechanism(s) by which streptococci adapt to host environments. Additionally, we will address how streptococcal infections trigger host stress responses; however, the mechanism by which bacterial components modulate host stress responses remains largely unknown.
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Affiliation(s)
- Cuong Thach Nguyen
- School of Pharmacy, Sungkyunkwan University, Su-Won, 16419, Republic of Korea
| | - Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Su-Won, 16419, Republic of Korea
| | - Dong-Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Su-Won, 16419, Republic of Korea.
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27
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Seong MW, Cho A, Park HW, Seo SH, Lim BC, Seol D, Cho SI, Park SS, Chae JH. Clinical applications of next-generation sequencing-based gene panel in patients with muscular dystrophy: Korean experience. Clin Genet 2015; 89:484-488. [PMID: 26060040 DOI: 10.1111/cge.12621] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 06/01/2015] [Accepted: 06/03/2015] [Indexed: 11/30/2022]
Abstract
Muscular dystrophy (MD) is a genetically and clinically heterogeneous group of disorders. Here, we performed targeted sequencing of 18 limb-girdle MD (LGMD)-related genes in 35 patients who were highly suspected of having MD. We identified one or more pathogenic variants in 23 of 35 patients (65.7%), and a genetic diagnosis was performed in 20 patients (57.1%). LGMD2B was the most common LGMD type, followed by LGMD1B, LGMD2A, and LGMD2G. Among the three major LGMD types in this group, LGMD1B was correlated with the lowest creatine kinase (CK) levels and the earliest onset, whereas LGMD2B was correlated with the highest CK levels and the latest onset. Thus, next-generation sequencing-based gene panels can be a helpful tool for the diagnosis of MDs, particularly in young children and those displaying atypical symptoms.
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Affiliation(s)
- M-W Seong
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - A Cho
- Department of Pediatrics, College of Medicine, Ewha Womans University, Seoul, Korea
| | - H W Park
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - S H Seo
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - B C Lim
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - D Seol
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - S I Cho
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - S S Park
- Departments of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - J H Chae
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
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Park SS, Kwon HY, Tran TDH, Choi MH, Jung SH, Lee S, Briles DE, Rhee DK. ClpL is a chaperone without auxiliary factors. FEBS J 2015; 282:1352-67. [PMID: 25662392 DOI: 10.1111/febs.13228] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 01/29/2015] [Accepted: 02/04/2015] [Indexed: 12/13/2022]
Abstract
Caseinolytic protease L (ClpL) is a member of the heat shock protein (Hsp) 100 family, which is found mostly in Gram-positive bacteria. Here, ClpL, a major HSP in Streptococcus pneumoniae (pneumococcus), was biochemically characterized in vitro. Recombinant ClpL shows nucleotide hydrolase, refolding, holdase and disaggregation activity using either Mg(2+) or Mn(2+) and does not require the DnaK system for chaperone activity. ClpL exhibits two features distinct from other HSP100 family proteins: (a) Mn(2+) enhances hydrolase activity, as well as chaperone activity; and (b) NTPase activity. ClpL forms a hexamer in the presence of ADP, ATP and ATP-γ-S. Mutational analysis using double-mutant proteins mutated at the two Walker A motifs (K127A/T128A and K458A/T459A) revealed that both nucleotide-binding domains are involved in chaperone activity, ATP hydrolase activity and hexamerization. Overall, pneumococcal ClpL is a unique Mn(2+) -dependent Hsp100 family member that has chaperone activity without other co-chaperones.
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Affiliation(s)
- Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Suwon, Korea
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29
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Thinda S, Lam K, Park SS. Unintentional secondary exogenous corticosteroid exposure and central serous chorioretinopathy. Eye (Lond) 2015; 29:577-9. [PMID: 25592121 DOI: 10.1038/eye.2014.328] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 12/07/2014] [Indexed: 11/09/2022] Open
Abstract
PURPOSE The purpose of this study is to describe a possible association between unintentional secondary exogenous corticosteroid exposure and central serous chorioretinpathy (CSCR). METHODS A retrospective review of three patients diagnosed with CSCR in one or both eyes and a history of possible unintentional secondary corticosteroid exposure. Clinical history, exam findings, optical coherence tomography, fluorescein angiography, and clinical course were reviewed. RESULTS Three patients, who did not use corticosteroids, reported suspected unintentional secondary corticosteroid exposure from living with family members or partners using dermatologic corticosteroid cream and/or inhalers frequently. Two of the three patients had a history of recurrent CSCR, one patient involving both eyes. After taking precautions to avoid secondary corticosteroid exposure, all three patients had complete resolution of CSCR without further recurrence during follow-up ranging from 2 to 4 years. CONCLUSIONS Patients with CSCR should be queried for both primary and possible unintentional secondary routes of corticosteroid exposure, which may contribute to this condition.
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Affiliation(s)
- S Thinda
- Department of Ophthalmology and Vision Science, University of California Davis Eye Center, Sacramento, CA, USA
| | - K Lam
- Department of Ophthalmology and Vision Science, University of California Davis Eye Center, Sacramento, CA, USA
| | - S S Park
- Department of Ophthalmology and Vision Science, University of California Davis Eye Center, Sacramento, CA, USA
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Nguyen CT, Le NT, Tran TDH, Kim EH, Park SS, Luong TT, Chung KT, Pyo S, Rhee DK. Streptococcus pneumoniae ClpL modulates adherence to A549 human lung cells through Rap1/Rac1 activation. Infect Immun 2014; 82:3802-10. [PMID: 24980975 PMCID: PMC4187815 DOI: 10.1128/iai.02012-14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 06/12/2014] [Indexed: 11/20/2022] Open
Abstract
Caseinolytic protease L (ClpL) is a member of the HSP100/Clp chaperone family, which is found mainly in Gram-positive bacteria. ClpL is highly expressed during infection for refolding of stress-induced denatured proteins, some of which are important for adherence. However, the role of ClpL in modulating pneumococcal virulence is poorly understood. Here, we show that ClpL impairs pneumococcal adherence to A549 lung cells by inducing and activating Rap1 and Rac1, thus increasing phosphorylation of cofilin (inactive form). Moreover, infection with a clpL mutant (ΔclpL) causes a greater degree of filopodium formation than D39 wild-type (WT) infection. Inhibition of Rap1 and Rac1 impairs filopodium formation and pneumococcal adherence. Therefore, ClpL can reduce pneumococcal adherence to A549 cells, likely via modulation of Rap1- and Rac1-mediated filopodium formation. These results demonstrate a potential role for ClpL in pneumococcal resistance to host cell adherence during infection. This study provides insight into further understanding the interactions between hosts and pathogens.
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Affiliation(s)
| | - Nhat-Tu Le
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | | | - Eun-Hye Kim
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Sang-Sang Park
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | | | - Kyung-Tae Chung
- Department of Clinical Laboratory Science, Dong-Eui University, Busan, South Korea
| | - Suhkneung Pyo
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Dong-Kwon Rhee
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
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Abstract
The link between inflammation and tumourisation has long been considered as a key event in clinical cancer development. Inflammation and inflammatory diseases can be caused by many factors including infectious agents, altered genetics and various degrees of injuries from simple cuts to traumatic wounds, such as those suffered in battlefield. Improved management of all wound types is critical in protecting affected individuals against the development of tumourisation cues, which may potentially lead to cancer development. There have been numerous studies on the mechanism of inflammation-induced tumourisation. Thus, in this mini review, we summarised evidence demonstrating the potential link between infectious agents and their moonlight proteins, wounding, trauma, overactive repair mechanisms, and carcinogenesis.
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Affiliation(s)
- S S Park
- PhD, Research Scientist, Diagnostics and Translational Research Center, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Gaithersburg, US
| | - M J Izadjoo
- PhD, Senior Distinguished Scientist, Diagnostics and Translational Research Center, The Henry M. Jackson Foundation for the Advancement of Military Medicine, Gaithersburg, US
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32
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Seo SH, Hwang SM, Ko JM, Ko JS, Hyun YJ, Cho SI, Park H, Kim SY, Seong MW, Park SS. Identification of novel mutations in the VPS33B gene involved in arthrogryposis, renal dysfunction, and cholestasis syndrome. Clin Genet 2014; 88:80-4. [PMID: 24917129 DOI: 10.1111/cge.12442] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 05/22/2014] [Accepted: 06/09/2014] [Indexed: 11/29/2022]
Abstract
Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B and VIPAS39. Here, we report novel mutations identified in four patients with ARC syndrome. We analyzed the entire coding regions of the VPS33B and VIPAS39 genes by direct sequencing. To detect novel splice site mutations, mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. All four patients had compound heterozygous variants in the VPS33B gene. One patient had a previously reported splice site variant with unknown significance, c.239+5G>A, and a novel nonsense mutation, c.621G>A. The other three patients had the c.403+2T>A mutation, and each of them carried one of the splice site variants, c.239+5G>A or c.499-11G>A. c.239+5G>A and c.499-11G>A created novel splice sites which resulted in abnormal transcripts. No significant VIPAS39 mutation was detected in all patients. In patients suspected with ARC syndrome, mutation analysis of the VPS33B gene should be employed as a primary diagnostic test before performing invasive testing procedures such as organ biopsies. Performing mRNA analysis can be useful in predicting the pathogenic phenotype when the mutation seems to affect a normal splicing mechanism.
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Affiliation(s)
- S H Seo
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
| | - S M Hwang
- Department of Laboratory Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - J M Ko
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul, South Korea
| | - J S Ko
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul, South Korea
| | - Y J Hyun
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
| | - S I Cho
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
| | - H Park
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
| | - S Y Kim
- Department of Laboratory Medicine, National Medical Center, Seoul, South Korea
| | - M-W Seong
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
| | - S S Park
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
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Na YJ, Lee IH, Park SS, Lee SR. Effects of combination of rice straw with alfalfa pellet on milk productivity and chewing activity in lactating dairy cows. Asian-Australas J Anim Sci 2014; 27:960-4. [PMID: 25050037 PMCID: PMC4093563 DOI: 10.5713/ajas.2013.13597] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 11/16/2013] [Accepted: 03/14/2014] [Indexed: 11/27/2022]
Abstract
An experiment was conducted to determine the effects of diets containing coarse-texture rice straw and small particle size alfalfa pellets as a part of total mixed ration (TMR) on milk productivity and chewing activity in lactating dairy cows. Sixteen multiparous Holstein dairy cows (670±21 kg body weight) in mid-lactation (194.1±13.6 days in milk) were randomly assigned to TMR containing 50% of timothy hay (TH) or TMR containing 20% of rice straw and 30% of alfalfa pellet mixture (RSAP). Geometric mean lengths of TH and RSAP were found to be 5.8 and 3.6, respectively. Dry matter intake, milk yield and milk composition were measured. Moreover, eating and ruminating times were recorded continuously using infrared digital camcorders. Milk yield and milk composition were not detected to have significant differences between TH and RSAP. Dry matter intake (DMI) did not significantly differ for cows fed with TH or RSAP. Although particle size of TH was larger than RSAP, eating, ruminating and total chewing time (min/d or min/kg of DMI) on TH and RSAP were similar. Taken together, our results suggest that using a proper amount of coarse-texture rice straw with high value nutritive alfalfa pellets may stimulate chewing activity in dairy cows without decreasing milk yield and composition even though the quantity of rice straw was 40% of TH.
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Hyun MH, Lee CH, Kim HJ, Tong Y, Park SS. Systematic review and meta-analysis of robotic surgery compared with conventional laparoscopic and open resections for gastric carcinoma. Br J Surg 2014; 100:1566-78. [PMID: 24264778 DOI: 10.1002/bjs.9242] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Robot-assisted gastrectomy (RAG) has been developed in the hope of improving surgical quality and overcoming the limitations of conventional laparoscopically assisted gastrectomy (LAG) and open gastrectomy (OG) for gastric cancer. The aim of this study was to determine the extent of evidence in support of these ideals. METHODS A systematic review of the three operation types (RAG, LAG and OG) was carried out to evaluate short-term outcomes including duration of operation, retrieved lymph nodes, estimated blood loss, resection margin status, technical postoperative complications and hospital stay. RESULTS Nine non-randomized observational clinical studies involving 7200 patients satisfied the eligibility criteria. RAG was associated with longer operating times than LAG and OG (weighted mean difference 61.99 and 65.73 min respectively; P ≤ 0.001). The number of retrieved lymph nodes and the resection margin length in RAG were comparable with those of LAG and OG. Estimated blood loss as significantly less in RAG than in OG (P = 0.002), but not LAG. Mean hospital stay for RAG was similar to that for LAG (P = 0.14). In contrast, hospital stay was significantly shorter, by a mean of 2.18 days, for RAG compared with OG (P < 0.001). Postoperative complications were similar for all three operative approaches. CONCLUSION Short-term oncological outcomes of RAG were comparable with those of the other approaches. LAG was a shorter procedure and less expensive than RAG. Future studies involving RAG should focus on minimizing duration of operation and reducing cost.
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Affiliation(s)
- M H Hyun
- Division of Upper Gastrointestinal Surgery, Department of Surgery, and
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Kim JH, Seong MW, Lee KE, Choi HJ, Ku EJ, Bae JH, Park SS, Choi SH, Kim SW, Shin C, Kim SY. Germline mutations and genotype-phenotype correlations in patients with apparently sporadic pheochromocytoma/paraganglioma in Korea. Clin Genet 2013; 86:482-6. [PMID: 24134185 DOI: 10.1111/cge.12304] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/27/2013] [Accepted: 10/15/2013] [Indexed: 11/29/2022]
Abstract
The aim of our study was to assess the frequency of germline mutations and develop the genetic testing strategy in patients with apparently sporadic pheochromocytoma/paraganglioma (PPGL) in Korea. We included 53 patients diagnosed with non-syndromic PPGL without a family history of PPGLs in three referral centers from 2004 to 2011. Succinate dehydrogenase complex B (SDHB), SDHD, Von Hippel-Lindau (VHL), and rearranged during transfection (RET) genes were examined by direct sequencing and multiple ligation-dependent probe amplification. The study patients were composed of 26 men and 27 women, and mean age was 50.1 ± 13.5 years. The frequency of germline mutations was 13.2% (7/53): RET (n = 2), VHL (n = 1), SDHB (n = 2), and SDHD (n = 2). Six of seven mutation carriers were diagnosed before the age of 50. One of two patients harboring an SDHB mutation had malignant PPGLs. One patient with multifocal head and neck paraganglioma (PGL) and pheochromocytoma (PHEO) carried a SDHD mutation. The carriers of germline mutations in patients with apparently sporadic PPGL were 13.2% in our study. We recommend genetic testing in patients below 50 years and SDHD genetic testing in patients with multifocal PPGLs. In malignant PPGLs, SDHB genetic testing may be performed.
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Affiliation(s)
- J H Kim
- Department of Internal medicine, Seoul National University College of Medicine, Seoul, South Korea
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Park SS, Kim DH, Jeon YP, Kim TW. Enhancement of the stabilization in white organic light-emitting diodes utilizing a color conversion layer containing CdSe/ZnS quantum dots. J Nanosci Nanotechnol 2013; 13:7194-7197. [PMID: 24245227 DOI: 10.1166/jnn.2013.8162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
White organic light emitting diodes (WOLEDs) were fabricated utilizing blue emitting organic light emitting diodes and color conversion layers containing CdSe/ZnS quantum dots (QDs). The best color purity of the WOLEDs was achieved by using the red and green QDs ratio of 1:9.5. Commission Internationale de l'Eclairage coordinates of the WOLEDs slightly shifted from (0.35, 0.33) to (0.35, 0.32) with increasing applied voltage from 9 to 14 V, indicative of a deep stabilized white color. Color tunable mechanisms of WOLEDs with a color conversion layer containing CdSe/ZnS QDs are described on the basis of the experimental results.
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Affiliation(s)
- S S Park
- Department of Electronics and Computer Engineering, Hanyang University, Seoul 133-791, Korea
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Park SS, Sanders DB, Smith BP, Ryan J, Plasencia J, Osborn MB, Wellnitz CM, Southard RN, Pierce CN, Arabia FA, Lane J, Frakes D, Velez DA, Pophal SG, Nigro JJ. Total artificial heart in the pediatric patient with biventricular heart failure. Perfusion 2013; 29:82-8. [PMID: 23868320 DOI: 10.1177/0267659113496580] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mechanical circulatory support emerged for the pediatric population in the late 1980s as a bridge to cardiac transplantation. The Total Artificial Heart (TAH-t) (SynCardia Systems Inc., Tuscon, AZ) has been approved for compassionate use by the Food and Drug Administration for patients with end-stage biventricular heart failure as a bridge to heart transplantation since 1985 and has had FDA approval since 2004. However, of the 1,061 patients placed on the TAH-t, only 21 (2%) were under the age 18. SynCardia Systems, Inc. recommends a minimum patient body surface area (BSA) of 1.7 m(2), thus, limiting pediatric application of this device. This unique case report shares this pediatric institution's first experience with the TAH-t. A 14-year-old male was admitted with dilated cardiomyopathy and severe biventricular heart failure. The patient rapidly decompensated, requiring extracorporeal life support. An echocardiogram revealed severe biventricular dysfunction and diffuse clot formation in the left ventricle and outflow tract. The decision was made to transition to biventricular assist device. The biventricular failure and clot formation helped guide the team to the TAH-t, in spite of a BSA (1.5 m(2)) below the recommendation of 1.7 m(2). A computed tomography (CT) scan of the thorax, in conjunction with a novel three-dimensional (3D) modeling system and team, assisted in determining appropriate fit. Chest CT and 3D modeling following implantation were utilized to determine all major vascular structures were unobstructed and the bronchi were open. The virtual 3D model confirmed appropriate device fit with no evidence of compression to the left pulmonary veins. The postoperative course was complicated by a left lung opacification. The left lung anomalies proved to be atelectasis and improved with aggressive recruitment maneuvers. The patient was supported for 11 days prior to transplantation. Chest CT and 3D modeling were crucial in assessing whether the device would fit, as well as postoperative complications in this smaller pediatric patient.
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Affiliation(s)
- S S Park
- 1Division of Cardiothoracic Surgery, Division of Cardiology, Division of Critical Care Medicine, Children's Heart Center, Division of Radiology, Phoenix Children's Hospital, Phoenix, AZ, USA
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Abstract
The Fontan procedure represents the final stage of the transition to single ventricle physiology. Conversion of very complex congenital heart anatomy, such as hypoplastic left heart syndrome, double-outlet right ventricle or double-inlet left ventricle, to a single ventricle has grown in popularity as morbidity and mortality have improved. As these patients grow, survivors are at risk for impaired ventricular dysfunction, plastic bronchitis, protein-losing enteropathy and late failure. Late failing Fontan patients represent a particularly vexing scenario for clinicians, as the only durable treatment option is cardiac transplantation. However, in the short-term, some of these patients require support beyond medical management, with mechanical circulatory support via extracorporeal life support or a ventricular assist device. We report the successful bridge of an adolescent female post-Fontan conversion with late severe cardiac failure. The patient was initially resuscitated with extracorporeal life support, transitioned to a single Berlin Heart EXCOR® ventricular assist device and, subsequently, underwent successful cardiac transplantation.
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Affiliation(s)
- DB Sanders
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | - SR Sowell
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | - SS Park
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | - C Derby
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
- Cardon Children’s Hospital, Banner Desert Hospital, Mesa, AZ, USA
| | - BC Willis
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | - JE Lane
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | | | | | - SG Pophal
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
| | - JJ Nigro
- Scott and Laura Eller Congenital Heart Center, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Children’s Heart Center, Phoenix Children’s Hospital, Phoenix, AZ, USA
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Lee HY, Seong MW, Park SS, Hwang SS, Lee J, Park YS, Lee CH, Lee SM, Yoo CG, Kim YW, Han SK, Yim JJ. Diagnostic accuracy of Xpert® MTB/RIF on bronchoscopy specimens in patients with suspected pulmonary tuberculosis. Int J Tuberc Lung Dis 2013; 17:917-21. [PMID: 23621953 DOI: 10.5588/ijtld.12.0885] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE To determine the diagnostic accuracy of the Xpert® MTB/RIF assay using samples obtained through bronchoscopy in patients with suspected pulmonary tuberculosis (PTB). DESIGN We retrospectively reviewed the records of patients with suspected PTB for whom the Xpert MTB/RIF assay was performed on bronchoscopy specimens. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the diagnosis of active PTB were calculated for acid-fast bacilli (AFB) smear microscopy and the Xpert assay using culture of Mycobacterium tuberculosis from sputum or bronchoscopy specimens as a reference standard. RESULTS A total of 132 patients were included in the final analysis. Of these, 38 had culture-confirmed PTB. The sensitivity of the Xpert assay using bronchial washing or bronchoalveolar lavage (BAL) fluid for the diagnosis of PTB was 81.6%, and specificity was 100%. The PPV and NPV were 100% and 92.1%, respectively. The sensitivity and specificity of AFB smear microscopy were respectively 13.2% and 98.8%. CONCLUSION The Xpert assay on bronchoscopy specimens provided an accurate diagnosis of PTB in patients who had a negative AFB smear or who could not produce sputum.
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Affiliation(s)
- H Y Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine and Lung Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
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Stamper BD, Mecham B, Park SS, Wilkerson H, Farin FM, Beyer RP, Bammler TK, Mangravite LM, Cunningham ML. Transcriptome correlation analysis identifies two unique craniosynostosis subtypes associated with IRS1 activation. Physiol Genomics 2012; 44:1154-63. [PMID: 23073384 DOI: 10.1152/physiolgenomics.00085.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The discovery of causal mechanisms associated with nonsyndromic craniosynostosis has proven to be a difficult task due to the complex nature of the disease. In this study, differential transcriptome correlation analysis was used to identify two molecularly distinct subtypes of nonsyndromic craniosynostosis, termed subtype A and subtype B. In addition to unique correlation structure, subtype A was also associated with high IGF pathway expression, whereas subtype B was associated with high integrin expression. To identify a pathologic link between altered gene correlation/expression and the disease state, phosphorylation assays were performed on primary osteoblast cell lines derived from cases within subtype A or subtype B, as well as on primary osteoblast cell lines with novel IGF1R variants previously reported by our lab (Cunningham ML, Horst JA, Rieder MJ, Hing AV, Stanaway IB, Park SS, Samudrala R, Speltz ML. Am J Med Genet A 155A: 91-97, 2011). Elevated IRS1 (pan-tyr) and GSK3β (ser-9) phosphorylation were observed in two novel IGF1R variants with receptor L domain mutations. In subtype A, a hypomineralization phenotype coupled with decreased phosphorylation of IRS1 (ser-312), p38 (thr-180/tyr-182), and p70S6K (thr-412) was observed. In subtype B, decreased phosphorylation of IRS1 (ser-312) as well as increased phosphorylation of Akt (ser-473), GSK3β (ser-9), IGF1R (tyr-1135/tyr-1136), JNK (thr-183/tyr-187), p70S6K (thr-412), and pRPS6 (ser-235/ser-236) was observed, thus implicating the activation of IRS1-mediated Akt signaling in potentiating craniosynostosis in this subtype. Taken together, these results suggest that despite the stimulation of different pathways, activating phosphorylation patterns for IRS1 were consistent in cell lines from both subtypes and the IGF1R variants, thus implicating a key role for IRS1 in the pathogenesis of nonsyndromic craniosynostosis.
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Affiliation(s)
- B D Stamper
- Center for Tissue and Cell Sciences, Seattle Children's Research Institute, Seattle, Washington 98101, USA.
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Kim SY, Kim H, Kim SY, Ra EK, Joo SI, Shin S, Seong MW, Yoo CG, Kim EC, Park SS. The Xpert® MTB/RIF assay evaluation in South Korea, a country with an intermediate tuberculosis burden. Int J Tuberc Lung Dis 2012; 16:1471-6. [PMID: 22981162 DOI: 10.5588/ijtld.11.0602] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING A central hospital laboratory in South Korea. OBJECTIVE To evaluate the usefulness of the Xpert® MTB/RIF assay in a country with an intermediate tuberculosis burden. DESIGN A total of 71 real-time polymerase chain reaction-positive sputum sediments were tested within 24 h by the Xpert MTB/RIF assay. Mycobacterium tuberculosis detection was compared with smear microscopy and culture. Rifampicin (RMP) resistance was compared with a culture-based method and rpoB gene sequencing. We also assessed the limit of detection for mutant proportions and time savings in diagnosis. RESULTS The Xpert MTB/RIF assay detected M. tuberculosis in 71 (100%) specimens (32 smear-positive, 39 smear-negative). This assay showed 100% (62/62) concordance with drug resistance confirmed by culture and 98.4% (61/62) concordance with sequencing. A specimen containing approximately 50% of mutant p.His526Tyr was falsely interpreted as wild-type bacilli by this assay. The minimal detection ratio was 5:1 of mutant vs. wild-type cells. The median time saved was 18.5 days (range 9-30) for the diagnosis of M. tuberculosis and 81.5 days (65-136) for RMP susceptibility in smear-negative, culture-positive patients. CONCLUSIONS The Xpert MTB/RIF assay showed high sensitivity in detecting M. tuberculosis with information on RMP resistance, and had a more rapid time to diagnosis compared to conventional tests; however, the location and amount of mutation may affect test sensitivity.
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Affiliation(s)
- S Y Kim
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul, South Korea
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Seo SH, Ahn HS, Yu YS, Kang HJ, Park KD, Cho SI, Park JS, Hyun YJ, Kim JY, Seong MW, Park SS. Mutation spectrum of RB1 gene in Korean bilateral retinoblastoma patients using direct sequencing and gene dosage analysis. Clin Genet 2012; 83:494-6. [PMID: 22963398 DOI: 10.1111/j.1399-0004.2012.01954.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 07/24/2012] [Accepted: 08/07/2012] [Indexed: 11/29/2022]
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Jeon K, Choi WI, An JS, Lim SY, Kim WJ, Park GM, Park SS, Choi HS, Lee BH, Choi JC, Na MJ, Park J, Kim JY. Paradoxical response in HIV-negative patients with pleural tuberculosis: a retrospective multicentre study. Int J Tuberc Lung Dis 2012; 16:846-51. [PMID: 22507441 DOI: 10.5588/ijtld.11.0642] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE To evaluate the incidence, clinical characteristics and predicting factors for the development of paradoxical response in human immunodeficiency virus negative patients with isolated pleural tuberculosis (TB). DESIGN A multicentre, retrospective cohort study including 458 patients who were diagnosed and treated with isolated pleural TB between March 2005 and February 2010. RESULTS Paradoxical response developed in 72 patients (16%) with isolated pleural TB. The mean time to development of paradoxical response was 8.8 ± 6.4 weeks after initiation of anti-tuberculosis treatment. The main presentation of paradoxical response was aggravation of pre-existing pleural effusion in 58 patients (81%). However, the majority of the patients who developed paradoxical response had no associated symptoms (n = 49, 68%). In multiple logistic regression analysis, development of paradoxical response was independently associated with the proportion of eosinophils (adjusted OR 1.293, 95%CI 1.077-1.553) and protein concentrations (adjusted OR 0.590, 95%CI 0.397-0.878) in the pleural fluid at the time of diagnosis. CONCLUSION Paradoxical response developed in 16% of the patients approximately 2 months after initiation of anti-tuberculosis treatment, presenting with aggravation of pre-existing pleural effusion. Development of paradoxical response was associated with the proportion of eosinophils and protein concentrations in the pleural fluid at the time of diagnosis.
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Affiliation(s)
- K Jeon
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
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Kim EH, Choi SY, Kwon MK, Tran TDH, Park SS, Lee KJ, Bae SM, Briles DE, Rhee DK. Streptococcus pneumoniae pep27 mutant as a live vaccine for serotype-independent protection in mice. Vaccine 2012; 30:2008-19. [DOI: 10.1016/j.vaccine.2011.11.073] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 11/19/2011] [Accepted: 11/19/2011] [Indexed: 10/14/2022]
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Mehrpouya M, Park SS. Prediction of atomic force microscope probe dynamics through the receptance coupling method. Rev Sci Instrum 2011; 82:125001. [PMID: 22225241 DOI: 10.1063/1.3664787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The increased growth in the use of tip-based sensing, manipulations, and fabrication of devices in atomic force microscopy (AFM) necessitates the accurate prediction of the dynamic behavior of the AFM probe. The chip holder, to which the micro-sensing device is attached, and the rest of the AFM system can affect the overall dynamics of the probe. In order to consider these boundary effects, we propose a novel receptance coupling method to mathematically combine the dynamics of the AFM setup and probe, based on the equilibrium and compatibility conditions at the joint. Once the frequency response functions of displacement over force at the tool tip are obtained, the dynamic interaction forces between the tip and the sample in nanoscale can be determined by measuring the probe tip displacement.
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Affiliation(s)
- M Mehrpouya
- Micro Engineering, Dynamics and Automation Laboratory (MEDAL), Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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Choi KJ, Lee HS, Yoon YS, Park SS, Kim JS, Jeong JJ, Choi YR. Distal metatarsal osteotomy for hallux varus following surgery for hallux valgus. ACTA ACUST UNITED AC 2011; 93:1079-83. [PMID: 21768632 DOI: 10.1302/0301-620x.93b8.26430] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We reviewed the outcome of distal chevron metatarsal osteotomy without tendon transfer in 19 consecutive patients (19 feet) with a hallux varus deformity following surgery for hallux valgus. All patients underwent distal chevron metatarsal osteotomy with medial displacement and a medial closing wedge osteotomy along with a medial capsular release. The mean hallux valgus angle improved from -11.6° pre-operatively to 4.7° postoperatively, the mean first-second intermetatarsal angle improved from -0.3° to 3.3° and the distal metatarsal articular angle from 9.5° to 2.3° and the first metatarsophalangeal joints became congruent post-operatively in all 19 feet. The mean relative length ratio of the metatarsus decreased from 1.01 to 0.99 and the mean American Orthopaedic Foot and Ankle Society score improved from 77 to 95 points. In two patients the hallux varus recurred. One was symptom-free but the other remained symptomatic after a repeat distal chevron osteotomy. There were no other complications. We consider that distal chevron metatarsal osteotomy with a medial wedge osteotomy and medial capsular release is a useful procedure for the correction of hallux varus after surgery for hallux valgus.
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Affiliation(s)
- K J Choi
- Choi Kyung Jin Orthopaedic Hospital, 369-26 Woobong Building 3F, Shindang-dong, Jung-gu, Seoul, Korea
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Kim SY, Seong MW, Jeon BS, Kim SY, Ko HS, Kim JY, Park SS. Phase analysis identifies compound heterozygous deletions of the PARK2 gene in patients with early-onset Parkinson disease. Clin Genet 2011; 82:77-82. [DOI: 10.1111/j.1399-0004.2011.01693.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Jeong JC, Lee H, Lee SW, Park JY, Ahn SY, Park H, Kim EC, Park SS, Ahn C, Oh KH. Fungal peritonitis due to Scedosporium prolificans. Perit Dial Int 2011; 31:213-5. [PMID: 21427256 DOI: 10.3747/pdi.2009.00234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Lee YJ, Park SS, Kim SY, Lee JY, Koo HK, Yoon HI. A case of systemic polyarteritis nodosa involving bronchial artery. Sarcoidosis Vasc Diffuse Lung Dis 2010; 27:164-168. [PMID: 21319600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis involving predominantly medium-sized muscular arteries. It commonly involves skin, kidney, cardiovascular system, gastrointestinal system, and neurological system. But bronchial artery involvement of PAN is rarely identified. We report a case of PAN with initial presentation of hemoptysis. On admission, chest radiograph and chest CT angiography revealed no focus of bleeding. Angiography showed a bronchial artery aneurysm and multiple arterial aneurysms in both renal, hepatic, mesenteric and branches of small bowel arteries. These findings were compatible with the diagnosis of PAN. The patient was started on steroid and cyclophosphamide.
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Affiliation(s)
- Y J Lee
- Division of Respiratory and Critical Care Medicine, Department of Internal Medicine and Lung Institute, Seoul National University Hospital, Seoul, Republic of Korea
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Malekian M, Trieu D, Owoc JS, Park SS, Hunter CJ. Investigation of the intervertebral disc and fused joint dynamics through experimental modal analysis and the receptance coupling method. J Biomech Eng 2010; 132:041004. [PMID: 20387967 DOI: 10.1115/1.4001114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Identification of intervertebral disc (IVD) dynamics is important in understanding the spine mechanism and behavior. This paper experimentally identifies the dynamics of the bovine caudal IVD using experimental modal analysis and the inverse receptance coupling method. Experimental modal analysis was performed on free-free mounted bovine caudal vertebrae joined by an IVD and a fused IVD joint. Shear, rotational, and axial dynamics of the joints are identified by curve fitting of the frequency response functions, and identifying the damping ratio, stiffness, and modal frequency in each axis. The identified dynamics are compared with the IVD joints with and without fusion. Results provide important insight into IVD dynamics and fused IVD dynamics. This method can be extended to identify human IVD joint dynamics.
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Affiliation(s)
- M Malekian
- Department of Mechanical and Manufacturing Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
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