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Park S, Patel SA, Torr EE, Dureke AGN, McIntyre AM, Skop AR. A protocol for isolating and imaging large extracellular vesicles or midbody remnants from mammalian cell culture. STAR Protoc 2023; 4:102562. [PMID: 37690025 PMCID: PMC10500451 DOI: 10.1016/j.xpro.2023.102562] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/14/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023] Open
Abstract
Traditionally, midbody remnants (MBRs) are isolated from cell culture medium using ultracentrifugation, which is expensive and time consuming. Here, we present a protocol for isolating MBRs or large extracellular vesicles (EVs) from mammalian cell culture using either 1.5% polyethylene glycol 6000 (PEG6000) or PEG5000-coated gold nanoparticles. We describe steps for growing cells, collecting media, and precipitating MBRs and EVs from cell culture medium. We then detail characterization of MBRs through immunofluorescent antibody staining and immunofluorescent imaging.
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Affiliation(s)
- Sungjin Park
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Smit A Patel
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Elizabeth E Torr
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | | | - Alina M McIntyre
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Ahna R Skop
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA.
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Dhere VR, Schuster DM, Goyal S, Schreibmann E, Hershatter B, Patel SA, Shelton JW, Hanasoge S, Patel PR, Sebastian N, Lawal IO, Jani A. Biochemical Relapse-Free Survival in Post-Prostatectomy Patients Receiving 18F-Fluciclovine-Guided Prostate Bed Only Radiation: Post-Hoc Analysis of a Prospective Randomized Trial. Int J Radiat Oncol Biol Phys 2023; 117:e376. [PMID: 37785277 DOI: 10.1016/j.ijrobp.2023.06.2482] [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) Whole pelvis (WP) radiation therapy (XRT) significantly improved biochemical relapse free survival (bRFS) compared to prostate-bed (PB)-only XRT in RTOG 0534, yet increased toxicity and was performed in an era prior to PET staging (Pollack et al, Lancet, 2022). Separately, 18F-fluciclovine PET/CT (PET)-guided post-prostatectomy XRT demonstrated improved bRFS compared to XRT guided by conventional imaging alone. We hypothesized that patients whose decisions were changed from whole pelvic XRT to PB-only XRT after PET imaging would have bRFS that was (a) not significantly different than patients initially planned for PB-only XRT, and (b) significantly improved over patients planned for WP XRT without PET guidance. MATERIALS/METHODS We conducted a post-hoc analysis of a prospective, randomized, single-institution trial comparing conventional (Arm A) v. PET-guided (Arm B) post-prostatectomy XRT. For patients randomized to Arm B, pre-PET treatment field decisions were recorded, and post-fluciclovine fields were rigidly defined per protocol: pN0 patients with no pelvic or extrapelvic PET uptake received PB-only XRT. Three- and four-year bRFS were compared in patients initially planned for WP with change to PB-only XRT [Arm B (WP→PB)] v Arm B patients initially planned for PB-only with final XRT to PB-only [Arm B(PB→PB)] & Arm A patients treated with whole pelvic XRT [Arm A(WP)] using Z test and log-rank test. Demographics were compared using Chi-square test, Fisher's exact test, or ANOVA as appropriate. RESULTS We identified 10 Arm B (WP→PB), 31 Arm B (PB→PB), and 25 Arm A (WP) patients. Androgen deprivation was used in 50.0% of Arm B (WP→PB) and 3.2% of Arm B (PB→PB) patients, p<0.01. Mean pre-XRT PSA was significantly higher (1.56 v 0.32 ng/mL, respectively, p<0.01) in Arm B (WP→PB) v Arm B (PB→PB) patients, however, there was no significant difference in extracapsular extension (p = 1.00), seminal vesical invasion (p = 1.00), Gleason score ≥8 (p = 0.58) or margin positivity (p = 0.73) between cohorts. Three- and four-year bRFS was 80% in Arm B (WP→PB) & 87.4% in Arm B (PB→PB), p = 0.47, respectively. Arm A (WP) patients had significantly worse three- (35.2%) and four-year (13.2%) bRFS compared to Arm B (WP→PB), p<0.01. CONCLUSION Patients initially planned for WP XRT whose treatment field decisions were changed to PB-only XRT after PET guidance had, in this post-hoc analysis, (a) relapse rates not significantly different than patients initially planned for PB-only XRT and (b) improved relapse rates over patients treated with WP XRT without PET guidance. PET-guided volume de-escalation in selected patients may be one approach to mitigating excess toxicity seen with WP XRT without compromising outcomes and warrants further exploration.
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Affiliation(s)
- V R Dhere
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - D M Schuster
- Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA
| | - S Goyal
- Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Atlanta, GA
| | - E Schreibmann
- Winship Cancer Institute of Emory University, Department of Radiation Oncology, Atlanta, GA
| | - B Hershatter
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - S A Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - J W Shelton
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - S Hanasoge
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - P R Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - N Sebastian
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, OH
| | | | - A Jani
- Department of Radiation Oncology, Emory University, Atlanta, GA
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Wynne JF, Lei Y, Pan S, Wang T, Roper JR, Patel PR, Patel SA, Godette KD, Jani A, Yang X. Rapid Unpaired CBCT-Based Synthetic CT for CBCT-Guided Adaptive Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:S179. [PMID: 37784444 DOI: 10.1016/j.ijrobp.2023.06.2524] [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) Quantitative cone beam CT (CBCT) is the foundation for image-guided radiation therapy, improving treatment setup, tumor delineation and dose calculation. However, CBCT images suffer from severe artifacts, limiting clinical utility. Deep learning can overcome these limitations, boosting radiographic and dosimetric quality critical for online adaptive radiotherapy (ART). We hypothesize adapted contrastive unpaired translation (CUT), a recent method for image-to-image translation of photographic images, can improve CBCT quality while reducing compute time, demonstrating utility for ART. MATERIALS/METHODS Same-day CBCT and quality assurance CT (QACT) images acquired from 79 patients receiving proton therapy for prostate cancer between 2019 and 2020 at a single institution were retrospectively collected. QACT images were acquired for quality assurance in accordance with institutional policy. Seventy-nine patients yielded 102 non-contrast CBCT-QACT image sets. Each QACT image was rigidly registered to the corresponding CBCT and resampled to 1 × 1 × 2 mm to establish uniform voxel size and spacing. CBCT images were randomly shuffled prior to input to the CUT model for unsupervised training and QACT-quality synthetic CT images were generated as outputs. We compared mean absolute error (MAE), structural similarity index measure (SSIM), and Fréchet inception distance (FID) against same-day QACT. RESULTS MAE, SSIM, and FID were compared for the CycleGAN and CUT data relative to input QACT and are reported as the mean across five-fold cross-validation ± standard error. CUT achieved superior performance in MAE (19.5 ± 3.9 HU vs. cycleGAN 47.1 ± 25.4) and FID (31.5 ± 6.6 vs cycleGAN 75.9 ± 41.3). MAE indicates pixel-level correspondence to QACT HU intensity values, making the synthetic outputs of CUT useful for dose calculations during ART. FID further demonstrates perceptual visual similarity. SSIM for CycleGAN (0.7 ± 0.2) and CUT (0.8 ± 0.0) were similar, indicating acceptable reproducibility of global structure. CUT was faster and lighter than CycleGAN. CycleGAN contained a total of 28,286,000 parameters; CUT contained 14,703,000, approximately half that of CycleGAN. As a result, CycleGAN computes on a single CT image slice over 0.33s while CUT requires just 0.18s. CONCLUSION The contrastive method investigated here was demonstrated to be faster and more accurate than CycleGAN, requiring fewer networks and parameters to achieve superior performance. We demonstrated anatomic boundary preservation and HU fidelity superior to cycleGAN while significantly reducing compute time. We plan to investigate the use of these synthetic CT images in automated segmentation prior to exploration of CUT in a prospective setting.
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Affiliation(s)
- J F Wynne
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - Y Lei
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - S Pan
- Emory University School of Medicine Department of Radiation Oncology, Atlanta, GA
| | - T Wang
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - J R Roper
- Department of Radiation Oncology, Emory University, Atlanta, GA
| | - P R Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - S A Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - K D Godette
- Winship Cancer Institute, Department of Radiation Oncology, Emory University, Atlanta, GA
| | - A Jani
- Department of Radiation Oncology, Emory University, Atlanta, GA
| | - X Yang
- Department of Radiation Oncology, Emory University, Atlanta, GA
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Sebastian N, Goyal S, Liu Y, Patel PR, Hanasoge S, Dhere VR, Shelton JW, Godette KD, Jani A, Hershatter B, Fischer-Valuck B, Patel SA. Association of Radiation Facility Volume with Overall Survival in Patients with Very High-Risk Prostate Cancer Treated with Radiation and Androgen Deprivation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e434-e435. [PMID: 37785414 DOI: 10.1016/j.ijrobp.2023.06.1604] [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) Studies suggest an association of treatment at high volume facilities with improved survival in cancer patients receiving surgery or radiation therapy. This association has not been studied in patients with very high-risk prostate cancer, who are treated using a multimodality approach that often requires specialized care with advanced diagnostic imaging, complex radiotherapeutic planning, and multidrug antiandrogen regimens. We used the National Cancer Database (NCDB) to study the association of radiation treatment facility volume (FV) with overall survival (OS). MATERIALS/METHODS We selected for patients with very high risk, localized prostate cancer by NCCN criteria (cT3b-T4, primary Gleason pattern 5, >4 cores with grade group 4-5, and/or 2-3 high risk features). We included patients who received hormone therapy with either external beam radiation to a dose of ≥60 Gy or external beam radiation to a dose of ≥45 Gy combined with brachytherapy. Association of FV with OS was evaluated through a bias-adjusted log-rank test to identify the optimal cut point of FV for dichotomization. Kaplan-Meier curves were used to study the association of binary FV with overall survival (OS) with and without IPTW (inverse probability treatment weighting) balancing the following confounders: age, race, median income, education, insurance, academic treatment facility, Charlson comorbidity score, T stage, PSA, Gleason score, total radiation dose, year of diagnosis, and patient distance from treatment facility. Cox proportional hazards model was built using backward variable selection strategy (α of 0.05 for removal). RESULTS We identified 25,219 very high-risk prostate cancer patients by NCCN criteria (median follow up 57.36 months; 95% CI 56.67 - 58.09) diagnosed between 2004 and 2015. High FV (n = 6,438) was associated with better OS on univariable analysis (hazard ratio [HR] = 0.81; 95% confidence interval [CI] 0.77 - 0.86; p < 0.001) and multivariable analysis (HR = 0.89; 95% CI 0.84 - 0.95; p < 0.001). Other factors associated with improved OS on multivariable analysis included younger age, non-white/black race, higher income, private insurance, academic/research treatment facility, lower comorbidity, lower T-stage, lower PSA, and lower Gleason score. After IPTW adjustment, high FV remained associated with better OS (HR = 0.90; 95% CI 0.85 - 0.95; p < 0.001). CONCLUSION Patients with NCCN very high-risk prostate cancer treated at a radiation facility with high case volume had better OS than patients treated at a facility with low volume, after adjustment for confounders. This may suggest that for very high-risk patients, outcomes may be improved by the expertise and optimal multidisciplinary care that typically accompany high facility treatment volume.
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Affiliation(s)
- N Sebastian
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, OH
| | - S Goyal
- Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Atlanta, GA
| | - Y Liu
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA
| | - P R Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - S Hanasoge
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - V R Dhere
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - J W Shelton
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - K D Godette
- Winship Cancer Institute, Department of Radiation Oncology, Emory University, Atlanta, GA
| | - A Jani
- Department of Radiation Oncology, Emory University, Atlanta, GA
| | - B Hershatter
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | | | - S A Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
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Corriher TJ, Janopaul-Naylor J, Liu Y, Dhere VR, Sebastian N, Weiss A, Hershatter B, Filson CP, Patel SA. Utilization of Radical Prostatectomy vs. Radiation Therapy for Gleason Grade Group 5 Prostate Cancer before and after USPSTF Grade D Recommendation against Prostate-Specific Antigen Screening in 2012. Int J Radiat Oncol Biol Phys 2023; 117:e374. [PMID: 37785273 DOI: 10.1016/j.ijrobp.2023.06.2478] [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) The 2012 United States Preventive Services Task Force (USPSTF) Grade D recommendation against prostate-specific antigen (PSA) screening has resulted in a shift to higher-stage prostate cancer (PC) at diagnosis. While incidence of low-risk prostate cancer has declined, more men are diagnosed with high-risk disease, and multimodal treatment is often required. The impact of this epidemiologic shift on practice patterns, specifically radical prostatectomy (RP) versus definitive radiation therapy (RT), for men with localized PC at high risk of recurrence is unknown. Herein, we evaluate the utilization of RP versus RT in the United States for Gleason grade group 5 (GG5) prostate cancer before and after 2012. MATERIALS/METHODS We identified 34,011 men with localized GG5 PC treated with (1) RP or (2) RT plus androgen deprivation therapy (ADT) between 2004 and 2017 in the National Cancer Database. We excluded those who were clinically node-positive, had metastatic disease, or received chemotherapy or palliative-intent treatment. Chi-square was used to compare the relative use of RP and RT before versus after January 1, 2012, corresponding to the year of USPSTF recommendation against PSA screening. Annual use of RP versus RT from 2004 to 2017 was compared in academic and non-academic centers using Cochran-Armitage test for trend. Joinpoint regression assessed if 2012 was significant for inflection of crude rates of RP. Finally, we modeled the effect of treatment year (i.e., 2012-2017 versus 2004-2011) on use of RP using multivariable logistic regression. Sensitivity analysis tested an interaction term for facility type (i.e., academic versus community). Tests were two-sided with a 0.05 level of significance. RESULTS Of the eligible men, 10,745 (31.6%) had T3-T4 disease. Between 2004 and 2011, 36.5% (n = 5,483) underwent RP; between 2012 and 2017, 42.3% (n = 8,034) underwent RP (p = .02). Across all centers, use of RP increased from 31% to 41% (p for trend <.001). In academic centers, use of RP increased from 32% to 44% (p for trend <.001); in community centers, use of RP increased from 30% to 39% (p for trend <.001). 2012 was associated with significant inflection for increase in RP use in all centers. On multivariable analysis, there was an increased odds of receiving RP after 2012 (adjusted OR 1.34, 95% CI 1.28-1.40, p<.001). No differential effect by facility type was observed (p = .15). CONCLUSION Utilization of RP for GG5 PC has significantly increased in the United States over the past decade, particularly after the USPSTF Grade D recommendation against PSA screening in 2012. It remains unknown whether oncologic or functional outcomes may be compromised in this group of high-risk men, many of whom require post-prostatectomy RT and/or ADT. While historically rare, prospective comparison of RP versus RT+ADT for GG5 PC may be helpful given the evolving epidemiology of localized PC.
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Affiliation(s)
- T J Corriher
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - J Janopaul-Naylor
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - Y Liu
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA
| | - V R Dhere
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - N Sebastian
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - A Weiss
- Department of Urology, Emory University School of Medicine, Atlanta, GA
| | - B Hershatter
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - C P Filson
- Department of Urology, Emory University School of Medicine, Atlanta, GA
| | - S A Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
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Janopaul-Naylor J, Corriher TJ, Switchenko J, Hanasoge S, Esdaille A, Mahal BA, Filson CP, Patel SA. Disparities in Time to Prostate Cancer Treatment Initiation before and after the Affordable Care Act. Int J Radiat Oncol Biol Phys 2023; 117:e28. [PMID: 37785048 DOI: 10.1016/j.ijrobp.2023.06.709] [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) Delayed access to care may contribute to disparities in prostate cancer (PCa). The Affordable Care Act (ACA) aimed at increasing access and reducing healthcare disparities, but its impact on timely treatment initiation for men with PCa is unknown. MATERIALS/METHODS Men with intermediate- and high-risk PCa diagnosed 2010-2016 and treated with curative surgery or radiotherapy were identified in the National Cancer Database. Multivariable logistic regression modeled the effect of race and insurance type on treatment delay >180 days after diagnosis to start of surgery, radiotherapy, or hormonal therapy. Cochran-Armitage test measured annual trends in delays, and join point regression assessed if 2014, the year the ACA became fully operationalized, was significant for inflection in crude rates of major delays. RESULTS Of 422,506 eligible men, 18,720 (4.4%) experienced >180-day delay in treatment initiation. Compared to White patients, Black (OR 1.79, 95% CI 1.72-1.87, p<.001) and Hispanic (OR 1.37, 95% CI 1.28-1.48, p<.001) patients had higher odds of delay. These disparities persisted when analyzing only patients treated after 2014 or for patients who had Medicare or Private insurance. Compared to uninsured patients, those with Medicaid had no difference in odds of delay (OR 0.94, 95% CI 0.84-1.06, p = .31), while those with private insurance (OR 0.57, 95% CI 0.52-0.63, p<.001) or Medicare (OR 0.64, 95% CI 0.58-0.70, p<.001) had lower odds of delay. These disparities persisted when analyzing only patients treated after 2014. Mean time to treatment significantly increased from 2010 to 2016 across all racial/ethnic groups (trend p<.001); 2014 was associated with a significant inflection for increase in rates of major delays. CONCLUSION The impact of race and insurance status were independently associated with longer delays to PCa treatment in the US. These disparities were unaffected by implementation of the ACA. In fact, implementation of ACA was associated with increased delays in treatment initiation for all men, regardless of race. As the epidemiology of newly diagnosed prostate cancer in the United States continues to shift due to tempered screening and the COVID pandemic, further work will be needed to increase equity in prostate cancer care.
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Affiliation(s)
- J Janopaul-Naylor
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - T J Corriher
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | | | - S Hanasoge
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
| | - A Esdaille
- Department of Urology, Emory University School of Medicine, Atlanta, GA
| | - B A Mahal
- Department of Radiation Oncology, University of Miami/Sylvester Comprehensive Cancer Center, Miami, FL
| | - C P Filson
- Department of Urology, Emory University School of Medicine, Atlanta, GA
| | - S A Patel
- Department of Radiation Oncology, Winship Cancer Institute of Emory University, Atlanta, GA
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Balaji G, Yadav G, Patel SA, Ramesh A, Nema S, Ramalingam T. Accuracy of Femoral Tunnel Placement between Anteromedial and Anterolateral Visualisation Portals in Anterior Cruciate Ligament Reconstruction - Outcomes of a CT based Cross-Sectional Study. Malays Orthop J 2023; 17:7-12. [PMID: 37583529 PMCID: PMC10424999 DOI: 10.5704/moj.2307.002] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 08/18/2022] [Indexed: 08/17/2023] Open
Abstract
Introduction Anatomical femoral tunnel placement is critical for anterior cruciate ligament reconstruction (ACLR). Tunnel placement may vary with different surgical techniques. The aim of this study was to compare the accuracy of femoral tunnel placement between the Anteromedial (AM) and Anterolateral (AL) visualisation portals on post-operative CT scans among a cohort of ACLR patients. Materials and methods This cross-sectional study was conducted from January 2018 to March 2020 after obtaining ethics clearance. Patients who went for arthroscopic ACLR in our institute were divided into an AM (group 1) and an AL (group 2) based on the visualisation portal for creating the femoral tunnel and a 3D CT scan was done. The femoral tunnel position was calculated in deep to shallow and high to low direction using the Bernard Hertel grid. Femoral tunnel angle was measured in the 2D coronal image. Statistical analysis was done with the data collected. Results Fifty patients with an average age of 26.36 (18-55) years ±7.216 SD were enrolled in the study. In this study, the AM technique was significantly more accurate (p<0.01) than the AL technique in terms of femoral tunnel angle. Furthermore, the deep to the shallow position was significantly (p= 0.018) closer to normative values, as determined by the chi-square test. The chances of error in tunnel angle in femoral condyle are 2.6 times greater in the AL technique (minimal clinical difference). Conclusion To conclude, in ACLR the anteromedial visualisation portal can facilitate accurate femoral tunnel placement compared to the anterolateral visualisation portal.
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Affiliation(s)
- G Balaji
- Department of Orthopaedics, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
| | - G Yadav
- Department of Orthopaedics, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
| | - S A Patel
- Department of Orthopaedics, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
| | - A Ramesh
- Department of Orthopaedics, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
| | - S Nema
- Department of Orthopaedics, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India
| | - T Ramalingam
- Department of Orthopaedics, Sarvajanik College of Physiotherapy Rampura, Surat, India
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Bohannon D, Janopaul-Naylor J, Rudra S, Yang X, Chang CW, Wang Y, Ma C, Patel SA, McDonald MW, Zhou J. Prediction of plan adaptation in head and neck cancer proton therapy using clinical, radiographic, and dosimetric features. Acta Oncol 2023:1-8. [PMID: 37335043 DOI: 10.1080/0284186x.2023.2224050] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 06/01/2023] [Indexed: 06/21/2023]
Abstract
PURPOSE Because proton head and neck (HN) treatments are sensitive to anatomical changes, plan adaptation (re-plan) during the treatment course is needed for a significant portion of patients. We aim to predict re-plan at plan review stage for HN proton therapy with a neural network (NN) model trained with patients' dosimetric and clinical features. The model can serve as a valuable tool for planners to assess the probability of needing to revise the current plan. METHODS AND MATERIALS Mean beam dose heterogeneity index (BHI), defined as the ratio of the maximum beam dose to the prescription dose, plan robustness features (clinical target volume (CTV), V100 changes, and V100 > 95% passing rates in 21 robust evaluation scenarios), as well as clinical features (e.g., age, tumor site, and surgery/chemotherapy status) were gathered from 171 patients treated at our proton center in 2020, with a median age of 64 and stages from I-IVc across 13 HN sites. Statistical analyses of dosimetric parameters and clinical features were conducted between re-plan and no-replan groups. A NN was trained and tested using these features. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of the prediction model. A sensitivity analysis was done to determine feature importance. RESULTS Mean BHI in the re-plan group was significantly higher than the no-replan group (p < .01). Tumor site (p < .01), chemotherapy status (p < .01), and surgery status (p < .01) were significantly correlated to re-plan. The model had sensitivities/specificities of 75.0%/77.4%, respectively, and an area under the ROC curve of .855. CONCLUSION There are several dosimetric and clinical features that correlate to re-plans, and NNs trained with these features can be used to predict HN re-plans, which can be used to reduce re-plan rate by improving plan quality.
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Affiliation(s)
- D Bohannon
- Department of Nuclear and Radiological Engineering, Georgia institute of Technology, Atlanta, GA, USA
| | - J Janopaul-Naylor
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - S Rudra
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - X Yang
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - C W Chang
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - Y Wang
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - C Ma
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - S A Patel
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - M W McDonald
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
| | - J Zhou
- Department of Radiation Oncology, Emory University, Atlanta, GA, USA
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Hassan M, Awadalla M, Tan TC, Scherrer-Crosbie M, Zhang L, Zlotoff DA, Bany Bakar R, Hickey SB, Patel SA, Januzzi JL, Passeri JJ, Keane F, Jimenez R, MacDonald SM, Neilan TG. Serial measurement of global longitudinal strain among women with breast cancer treated with proton radiation therapy. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2850] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Conventional photon radiotherapy (RT) for breast cancer is associated with reduction in global longitudinal strain (GLS), an increase in both troponin and N-terminal pro-B type natriuretic peptide (NT-proBNP), and incident heart failure. The cardiac radiation exposure with proton-RT is reduced and, thus may be associated with less cardiotoxicity.
Objectives
To test the effect of proton-RT on GLS, troponin and NT-proBNP.
Methods
A prospective observational single center study of 69 women being treated with proton-RT for breast cancer. Serial measurements of GLS, high-sensitivity cardiac troponin-I (hs-cTnI), and NT-proBNP were performed at pre-specified intervals (pre proton-RT, 4 weeks after completion of proton-RT and again at 2 months post proton-RT).
Results
The mean age was 46±11 years, BMI was 25.6±5.2 kg/m2, 32% had hypertension and mean radiation dose to the heart and left ventricle (LV) were 0.44 Gy and 0.12 Gy respectively. There was no change in LV ejection fraction (pre proton-RT vs. 4-weeks post proton-RT vs. 2 months post proton-RT, 65±5 vs. 66±5 vs. 64±4%, p=0.15), global GLS (−21.7±2.7 vs. −22.7±2.3 vs. −22.8±2.1%, p=0.24) or segmental GLS from pre-to post proton-RT. Similarly, there was no change in hs-cTnI or NT-proBNP with proton-RT. However, post proton-RT, we found that patients with a history of hypertension had lower GLS when compared to women without hypertension (−21.3±3.5 vs. −24.0±2.4%, p=0.006).
Conclusion
Proton-RT did not impact LV function, or associate with an increase in biomarkers. These data support the potential cardiac benefits of proton-RT compared to conventional RT.
Funding Acknowledgement
Type of funding sources: None.
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Affiliation(s)
- M Hassan
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
| | - M Awadalla
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
| | - T C Tan
- Westmead and Blacktown Hospitals, University of Western Sydney and School of Medical Sciences, Division of Cardiology, Blacktown, Australia
| | - M Scherrer-Crosbie
- Hospital of the University of Pennsylvania, Cardiovascular Medicine Division, Philadelphia, United States of America
| | - L Zhang
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
| | - D A Zlotoff
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
| | - R Bany Bakar
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
| | - S B Hickey
- Massachusetts General Hospital - Harvard Medical School, Radiation Oncology Department, Boston, United States of America
| | - S A Patel
- Massachusetts General Hospital - Harvard Medical School, Radiation Oncology Department, Boston, United States of America
| | - J L Januzzi
- Massachusetts General Hospital - Harvard Medical School, Division of Cardiology, Boston, United States of America
| | - J J Passeri
- Massachusetts General Hospital - Harvard Medical School, Division of Cardiology, Boston, United States of America
| | - F Keane
- Massachusetts General Hospital - Harvard Medical School, Radiation Oncology Department, Boston, United States of America
| | - R Jimenez
- Massachusetts General Hospital - Harvard Medical School, Radiation Oncology Department, Boston, United States of America
| | - S M MacDonald
- Massachusetts General Hospital - Harvard Medical School, Radiation Oncology Department, Boston, United States of America
| | - T G Neilan
- Massachusetts General Hospital - Harvard Medical School, Cardiovascular Imaging Research Center, Department of Radiology and Division of Cardiology, Boston, United States of America
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10
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Shah MK, Kondal D, Patel SA, Singh K, Devarajan R, Shivashankar R, Ajay VS, Menon VU, Varthakavi PK, Viswanathan V, Dharmalingam M, Bantwal G, Sahay RK, Masood MQ, Khadgawat R, Desai A, Prabhakaran D, Narayan KMV, Tandon N, Ali MK. Effect of a multicomponent intervention on achievement and improvements in quality-of-care indices among people with Type 2 diabetes in South Asia: the CARRS trial. Diabet Med 2020; 37:1825-1831. [PMID: 31479537 PMCID: PMC7051882 DOI: 10.1111/dme.14124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/28/2019] [Indexed: 11/30/2022]
Abstract
AIMS To evaluate whether and what combinations of diabetes quality metrics were achieved in a multicentre trial in South Asia evaluating a multicomponent quality improvement intervention that included non-physician care coordinators to promote adherence and clinical decision-support software to enhance physician practices, in comparision with usual care. METHODS Using data from the Centre for Cardiometabolic Risk Reduction in South Asia (CARRS) trial, we evaluated the proportions of trial participants achieving specific and combinations of five diabetes care targets (HbA1c <53 mmol/mol [7%], blood pressure <130/80 mmHg, LDL cholesterol <2.6 mmol/L, non-smoking status, and aspirin use). Additionally, we examined the proportions of participants achieving the following risk factor improvements from baseline: ≥11-mmol/mol (1%) reduction in HbA1c , ≥10-mmHg reduction in systolic blood pressure, and/or ≥0.26-mmol/l reduction in LDL cholesterol. RESULTS Baseline characteristics were similar in the intervention and usual care arms. Overall, 12.3%, 29.4%, 36.5%, 19.5% and 2.2% of participants in the intervention group and 16.2%, 38.3%, 31.6%, 11.3% and 0.8% of participants in the usual care group achieved any one, two, three, four or five targets, respectively. We noted sizeable improvements in HbA1c , blood pressure and cholesterol, and found that participants in the intervention group were twice as likely to achieve improvements in all three indices at 12 months that were sustained over 28 months of the study [relative risk 2.1 (95% CI 1.5,2.8) and 1.8 (95% CI 1.5,2.3), respectively]. CONCLUSIONS The intervention was associated with significantly higher achievement of and greater improvements in composite diabetes quality care goals. However, among these higher-risk participants, very small proportions achieved the complete group of targets, which suggests that achievement of multiple quality-of-care goals is challenging and that other methods may be needed in closing care gaps.
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Affiliation(s)
- M K Shah
- Department of Family and Preventive Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - D Kondal
- Centre of Excellence, Centre for Cardiometabolic Risk Reduction in South Asia, Public Health Foundation of India, Gurgaon, India
| | - S A Patel
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - K Singh
- Centre of Excellence, Centre for Cardiometabolic Risk Reduction in South Asia, Public Health Foundation of India, Gurgaon, India
| | - R Devarajan
- Centre of Excellence, Centre for Cardiometabolic Risk Reduction in South Asia, Public Health Foundation of India, Gurgaon, India
| | - R Shivashankar
- Centre for Chronic Disease Control India, Public Health Foundation of India, Gurgaon, India
| | - V S Ajay
- Centre of Excellence, Centre for Cardiometabolic Risk Reduction in South Asia, Public Health Foundation of India, Gurgaon, India
| | - V U Menon
- Department of Endocrinology and Diabetes, Amrita Institute of Medical Sciences, Kerala, India
| | - P K Varthakavi
- Department of Endocrinology, TNM College and BYL Nair Charity Hospital, Mumbai, India
| | - V Viswanathan
- MV Hospital for Diabetes & Diabetes Research Centre, Chennai, India
| | - M Dharmalingam
- Bangalore Endocrinology and Diabetes Research Centre, Karnataka, India
| | - G Bantwal
- Department of Endocrinology, St John's Medical College and Hospital, Karnataka, India
| | - R K Sahay
- Department of Endocrinology, Osmania General Hospital, Hyderabad, India
| | - M Q Masood
- Department of Medicine, Section of Endocrinology and Diabetes, Aga Khan University, Karachi, Pakistan
| | - R Khadgawat
- Department of Endocrinology and Metabolism, All India Institute of Medical Sciences, New Delhi, India
| | - A Desai
- Department of Medicine Endocrine Unit, Goa Medical College, Goa, India
| | - D Prabhakaran
- Department of Medicine Endocrine Unit, Goa Medical College, Goa, India
- Centre for Control of Chronic Conditions, Public Health Foundation of India, Gurgaon, India
| | - K M V Narayan
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - N Tandon
- Department of Medicine, Section of Endocrinology and Diabetes, Aga Khan University, Karachi, Pakistan
| | - M K Ali
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
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11
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Nehser M, Dark J, Schweitzer D, Campbell M, Zwicker J, Hitt DM, Little H, Diaz-Correa A, Holley DC, Patel SA, Thompson CM, Bridges RJ. System X c- Antiporter Inhibitors: Azo-Linked Amino-Naphthyl-Sulfonate Analogues of Sulfasalazine. Neurochem Res 2020; 45:1375-1386. [PMID: 31754956 PMCID: PMC10688270 DOI: 10.1007/s11064-019-02901-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 01/18/2023]
Abstract
The cystine/glutamate antiporter system Xc- (SXc-) mediates the exchange of intracellular L-glutamate (L-Glu) with extracellular L-cystine (L-Cys2). Both the import of L-Cys2 and the export of L-Glu take on added significance in CNS cells, especially astrocytes. When the relative activity of SXc- overwhelms the regulatory capacity of the EAATs, the efflux of L-Glu through the antiporter can be significant enough to trigger excitotoxic pathology, as is thought to occur in glioblastoma. This has prompted considerable interest in the pharmacological specificity of SXc- and the development of inhibitors. The present study explores a series of analogues that are structurally related to sulfasalazine, a widely employed inhibitor of SXc-. We identify a number of novel aryl-substituted amino-naphthylsulfonate analogues that inhibit SXc- more potently than sulfasalazine. Interestingly, the inhibitors switch from a competitive to noncompetitive mechanism with increased length and lipophilic substitutions, a structure-activity relationship that was previously observed with aryl-substituted isoxazole. These results suggest that the two classes of inhibitors may interact with some of the same domains on the antiporter protein and that the substrate and inhibitor binding sites may be in close proximity to one another. Molecular modeling is used to explore this possibility.
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Affiliation(s)
- M Nehser
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - J Dark
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - D Schweitzer
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - M Campbell
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - J Zwicker
- Deciphera Pharmaceuticals, Lawrence, KA, 66044, USA
| | - D M Hitt
- Chemistry Department, Carroll College, Helena, MT, 56925, USA
| | - H Little
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - A Diaz-Correa
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - D C Holley
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - S A Patel
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - C M Thompson
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA
| | - R J Bridges
- Department of Biomedical and Pharmaceutical Science, Center for Structural and Functional Neuroscience, Skaggs School of Pharmacy, University of Montana, Missoula, MT, 59812, USA.
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12
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Patel SA, Mahmood SS, Nguyen T, Yeap BY, Jimenez RB, Taghian AG, Meyersohn NM, Neilan TG, MacDonald SM. Abstract P2-11-04: Not presented. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p2-11-04] [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
This abstract was not presented at the symposium.
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Affiliation(s)
- SA Patel
- Massachusetts General Hospital, Boston, MA
| | - SS Mahmood
- Massachusetts General Hospital, Boston, MA
| | - T Nguyen
- Massachusetts General Hospital, Boston, MA
| | - BY Yeap
- Massachusetts General Hospital, Boston, MA
| | - RB Jimenez
- Massachusetts General Hospital, Boston, MA
| | - AG Taghian
- Massachusetts General Hospital, Boston, MA
| | | | - TG Neilan
- Massachusetts General Hospital, Boston, MA
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13
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Newell JL, Keyari CM, McDaniel SW, Diaz PJ, Natale NR, Patel SA, Bridges RJ. Novel di-aryl-substituted isoxazoles act as noncompetitive inhibitors of the system Xc(-) cystine/glutamate exchanger. Neurochem Int 2013; 73:132-8. [PMID: 24333322 DOI: 10.1016/j.neuint.2013.11.012] [Citation(s) in RCA: 9] [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: 10/07/2013] [Revised: 11/26/2013] [Accepted: 11/29/2013] [Indexed: 01/18/2023]
Abstract
The system xc(-) antiporter is a plasma membrane transporter that mediates the exchange of extracellular l-cystine with intracellular l-glutamate. This exchange is significant within the context of the CNS because the import of l-cystine is required for the synthesis of the antioxidant glutathione, while the efflux of l-glutamate has the potential to contribute to either excitatory signaling or excitotoxic pathology. Changes in the activity of the transport system have been linked to the underlying pathological mechanisms of a variety of CNS disorders, one of the most prominent of which is its highly enriched expression in glial brain tumors. In an effort to produce more potent system xc(-) blockers, we have been using amino-3-carboxy-5-methylisoxazole propionic acid (ACPA) as a scaffold for inhibitor development. We previously demonstrated that the addition of lipophilic aryl groups to either the #4 or #5 position on the isoxazole ring markedly increased the inhibitory activity at system xc(-). In the present work a novel series of analogues has been prepared in which aryl groups have been introduced at both the #4 and #5 positions. In contrast to the competitive action of the mono-substituted analogues, kinetic analyses indicate that the di-substituted isoxazoles block system xc(-)-mediated uptake of (3)H-l-glutamate into SNB-19 cells by a noncompetitive mechanism. These new analogues appear to be the first noncompetitive inhibitors identified for this transport system, as well as being among the most potent blockers identified to date. These diaryl-isoxazoles should be of value in assessing the physiological roles and molecular pharmacology of system xc(-).
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Affiliation(s)
- J L Newell
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - C M Keyari
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - S W McDaniel
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - P J Diaz
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - N R Natale
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - S A Patel
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States
| | - R J Bridges
- Center for Structural & Functional Neuroscience, Department of Biomedical & Pharmaceutical Sciences, Skaggs School of Pharmacy, University of Montana, Missoula, MT 59812, United States.
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14
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Patel SA, Shepard WD, Barros JA, Streckfus CF, Quock RL. In vitro evaluation of Midwest Caries ID: a novel light-emitting diode for caries detection. Oper Dent 2013; 39:644-51. [PMID: 24107098 DOI: 10.2341/13-114-l] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Traditional detection techniques have limits in diagnosing occlusal caries. Thus, more accurate methods are needed. This study evaluates the ability of the Midwest Caries ID (Midwest) to detect caries. METHODS Two hundred sixty-four extracted, nonrestored premolars and molars were cleaned and stored in 0.2% sodium azide. Teeth were divided into three groups of 88. One examination site on each occlusal surface was chosen. Each site was inspected by a calibrated examiner via visual, Midwest, and histologic exams. First, a visual exam was performed following the International Caries Detection and Assessment guidelines. Next, the same site was inspected using the Midwest device. Finally, the tooth was sectioned mesiodistally through the site. The half with greater caries progression was visualized under a stereomicroscope (64×). Histologic appearance was scored based on the Downer system. Data were analyzed using Kendall tau-b, partial correlation coefficients, and the receiver operating characteristics curve. RESULTS Overall, the Midwest scoring assessment correlated with histologic assessments (tau = 0.32; p<0.0001), but the visual exam had a stronger correlation (tau = 0.53; p<0.0001) with the histologic exam. The sensitivity and specificity of the Midwest was also reported at 0.56 and 0.84, compared with 0.92 and 0.43, respectively, for the visual exam. CONCLUSIONS Midwest Caries ID is a novel caries detection device that has limitations and should not be used as the sole means to detect occlusal caries.
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15
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Bowen SR, Nyflot MJ, Zeng J, Sandison GA, Patel SA, Kinahan PE. TU-E-141-09: Impact of Attenuation Correction Mode On 4D PET/CT for Target Definition in Lung Cancer Patients. Med Phys 2013. [DOI: 10.1118/1.4815437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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16
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Patel SA, Hoehn KL, Lawrence RT, Sawbridge L, Talbot NA, Tomsig JL, Turner N, Cooney GJ, Whitehead JP, Kraegen EW, Cleasby ME. Overexpression of the adiponectin receptor AdipoR1 in rat skeletal muscle amplifies local insulin sensitivity. Endocrinology 2012; 153:5231-46. [PMID: 22989629 PMCID: PMC3498583 DOI: 10.1210/en.2012-1368] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adiponectin is an adipokine whose plasma levels are inversely related to degrees of insulin resistance (IR) or obesity. It enhances glucose disposal and mitochondrial substrate oxidation in skeletal muscle and its actions are mediated through binding to receptors, especially adiponectin receptor 1 (AdipoR1). However, the in vivo significance of adiponectin sensitivity and the molecular mechanisms of muscle insulin sensitization by adiponectin have not been fully established. We used in vivo electrotransfer to overexpress AdipoR1 in single muscles of rats, some of which were fed for 6 wk with chow or high-fat diet (HFD) and then subjected to hyperinsulinemic-euglycemic clamp. After 1 wk, the effects on glucose disposal, signaling, and sphingolipid metabolism were investigated in test vs. contralateral control muscles. AdipoR1 overexpression (OE) increased glucose uptake and glycogen accumulation in the basal and insulin-treated rat muscle and also in the HFD-fed rats, locally ameliorating muscle IR. These effects were associated with increased phosphorylation of insulin receptor substrate-1, Akt, and glycogen synthase kinase-3β. AdipoR1 OE also caused increased phosphorylation of p70S6 kinase, AMP-activated protein kinase, and acetyl-coA carboxylase as well as increased protein levels of adaptor protein containing pleckstrin homology domain, phosphotyrosine binding domain, and leucine zipper motif-1 and adiponectin, peroxisome proliferator activated receptor-γ coactivator-1α, and uncoupling protein-3, indicative of increased mitochondrial biogenesis. Although neither HFD feeding nor AdipoR1 OE caused generalized changes in sphingolipids, AdipoR1 OE did reduce levels of sphingosine 1-phosphate, ceramide 18:1, ceramide 20:2, and dihydroceramide 20:0, plus mRNA levels of the ceramide synthetic enzymes serine palmitoyl transferase and sphingolipid Δ-4 desaturase, changes that are associated with increased insulin sensitivity. These data demonstrate that enhancement of local adiponectin sensitivity is sufficient to improve skeletal muscle IR.
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Affiliation(s)
- S A Patel
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, United Kingdom
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17
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Abstract
The aim of this in vitro study was to investigate the effect of the cariostatic and preventive agent silver diamine fluoride (SDF) on the microtensile bond strength of resin composite to dentin. Forty-two caries-free, extracted molars were flattened occlusally and apically using a diamond saw, and the exposed occlusal dentin was polished with a series of silicon carbide papers, all under water irrigation. The teeth were then randomly divided into six groups of seven teeth each that were treated as follows: 1) Peak SE self-etch bonding agent; 2) 12% SDF + Peak SE; 3) 38% SDF + Peak SE; 4) Peak LC etch-and-rinse bonding agent; 5) 12% SDF + Peak LC; and 6) 38% SDF + Peak LC. Four-millimeter buildups of Amelogen Plus were incrementally placed on all teeth; after a 24-hour storage period in distilled water, the specimens were sectioned perpendicular to the adhesive interface to produce beams of cross-sectional surface area measuring approximately 1 mm(2). The beams were placed on a microtensile testing machine, which utilized a single-speed pump motor and force gauge at 20 kgf × 0.01 second to record maximum tensile force before failure occurred. Two-way analysis of variance and post hoc Tukey tests were performed to compare the effects of the SDF on microtensile bond strength, with statistical significance set at α = 0.05. None of the experimental groups treated with different concentrations of SDF showed a significant difference in bond strength compared to the control groups, and there was no significant difference in bond strength between self-etch and etch-and-rinse groups. However, the effect of SDF on self-etch bonded teeth compared to etch-and-rinse bonded teeth was statistically significant (p=0.0363), specifically at the 12% concentration. SDF does not adversely affect the bond strength of resin composite to noncarious dentin.
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Affiliation(s)
- R L Quock
- University of Texas-Houston School of Dentistry, Restorative Dentistry & Biomaterials, Houston, TX, USA.
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18
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Linam JM, Chand RR, Broudy VC, Liu KC, Back AL, Lin EH, Patel SA. Evaluation of the impact of HIV serostatus, tobacco smoking and CD4 counts on epidermoid anal cancer survival. Int J STD AIDS 2012; 23:77-82. [DOI: 10.1258/ijsa.2011.011020] [Citation(s) in RCA: 17] [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: 11/18/2022]
Abstract
Tobacco smoking and HIV infection increase the risk of epidermoid anal cancer (EAC). No published studies have examined smoking and EAC outcomes, and the literature is discrepant regarding outcomes of HIV-positive patients with EAC. The goal of this study was to examine smoking history, HIV status and outcomes in EAC patients. We conducted a retrospective analysis of adults with invasive EAC treated in the University of Washington hospital system from 1 January 1994 to 31 December 2008. Sixty-three patients were included. Forty-seven patients (75%) had primary chemoradiation, of whom 42 (89%) completed therapy. Two patients (3%) received radiotherapy alone. Fourteen patients (22%) underwent primary surgery, of whom 11 (79%) underwent tumour excision and three (21%) abdominoperineal resection (APR). We analysed smoking history, HIV status and CD4 count (≥200 cells/μL/<200 cells/μL for HIV-positive patients) versus outcomes. Forty-five patients (71%) were in remission, and 44 (70%) were alive at last follow-up. Overall survival was significantly better for never-smokers than for ever-smokers. There were no differences in outcomes according to HIV status or CD4 counts. Patients with anal cancer who smoke have worse overall survival than non-smoking patients. HIV infection does not appear to affect anal cancer outcomes.
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Affiliation(s)
| | | | - V C Broudy
- Department of Medicine, University of Washington Medical Center
| | - K C Liu
- Department of Biostatistics, University of Washington, Seattle, WA, USA
| | - A L Back
- Department of Medicine, University of Washington Medical Center
| | - E H Lin
- Department of Medicine, University of Washington Medical Center
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19
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Ferreira LS, Cai S, Barros JA, Patel SA, Chen W, Marques MM. Effects of laser phototherapy and growth factors PDGF and BMP-2 on the odontogenic differentiation of dental pulp stem cells. Med Oral Patol Oral Cir Bucal 2012. [DOI: 10.4317/medoral.17643600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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20
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Patel S, Patel NJ, Patel SA. Simultaneous spectrophotometric estimation of imipramine hydrochloride and chlordiazepoxide in tablets. Indian J Pharm Sci 2011; 71:468-72. [PMID: 20502561 PMCID: PMC2865827 DOI: 10.4103/0250-474x.57304] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 05/20/2009] [Accepted: 08/13/2009] [Indexed: 11/05/2022] Open
Abstract
A binary mixture of imipramine HCl and chlordiazepoxide was determined by three different spectrophotometric methods. The first method involved determination of imipramine HCl and chlordiazepoxide using the simultaneous equations and the second method involved absorbance ratio method. Imipramine has absorbance maxima at 251 nm, chlordiazepoxide has absorbance maxima at 264.5 nm and isoabsorptive point is at 220 nm in methanol. Linearity was obtained in the concentration ranges of 1-25 and 1-10 μg/ml for Imipramine HCL and Chlordiazepoxide, respectively. The third method involved determination of these two drugs using the first-derivative spectrophotometric technique at 219 and 231.5 nm over the concentration ranges of 1-20 and 2-24 μg/ml with mean accuracies 99.46±0.78 and 101.43±1.20%, respectively. These methods were successively applied to pharmaceutical formulations because no interferences from the tablet excipients were found. The suitability of these methods for the quantitative determination of the compounds was proved by validation.
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Affiliation(s)
- Sejal Patel
- S. K. Patel College of Pharmaceutical Education and Research, Department of Pharmaceutical Chemistry, Ganpat University, Kherva, Mehsana-382 711, India
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Cleasby ME, Lau Q, Polkinghorne E, Patel SA, Leslie SJ, Turner N, Cooney GJ, Xu A, Kraegen EW. The adaptor protein APPL1 increases glycogen accumulation in rat skeletal muscle through activation of the PI3-kinase signalling pathway. J Endocrinol 2011; 210:81-92. [PMID: 21543456 PMCID: PMC3114475 DOI: 10.1530/joe-11-0039] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
APPL1 is an adaptor protein that binds to both AKT and adiponectin receptors and is hypothesised to mediate the effects of adiponectin in activating downstream effectors such as AMP-activated protein kinase (AMPK). We aimed to establish whether APPL1 plays a physiological role in mediating glycogen accumulation and insulin sensitivity in muscle and the signalling pathways involved. In vivo electrotransfer of cDNA- and shRNA-expressing constructs was used to over-express or silence APPL1 for 1 week in single tibialis cranialis muscles of rats. Resulting changes in glucose and lipid metabolism and signalling pathway activation were investigated under basal conditions and in high-fat diet (HFD)- or chow-fed rats under hyperinsulinaemic-euglycaemic clamp conditions. APPL1 over-expression (OE) caused an increase in glycogen storage and insulin-stimulated glycogen synthesis in muscle, accompanied by a modest increase in glucose uptake. Glycogen synthesis during the clamp was reduced by HFD but normalised by APPL1 OE. These effects are likely explained by APPL1 OE-induced increase in basal and insulin-stimulated phosphorylation of IRS1, AKT, GSK3β and TBC1D4. On the contrary, APPL1 OE, such as HFD, reduced AMPK and acetyl-CoA carboxylase phosphorylation and PPARγ coactivator-1α and uncoupling protein 3 expression. Furthermore, APPL1 silencing caused complementary changes in glycogen storage and phosphorylation of AMPK and PI3-kinase pathway intermediates. Thus, APPL1 may provide a means for crosstalk between adiponectin and insulin signalling pathways, mediating the insulin-sensitising effects of adiponectin on muscle glucose disposal. These effects do not appear to require AMPK. Activation of signalling mediated via APPL1 may be beneficial in overcoming muscle insulin resistance.
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Affiliation(s)
- M E Cleasby
- Department of Veterinary Basic Sciences, Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK.
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Lim PK, Patel SA, Gregory LA, Rameshwar P. Neurogenesis: role for microRNAs and mesenchymal stem cells in pathological states. Curr Med Chem 2010; 17:2159-67. [PMID: 20423304 DOI: 10.2174/092986710791299894] [Citation(s) in RCA: 20] [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] [Received: 01/22/2010] [Accepted: 04/25/2010] [Indexed: 11/22/2022]
Abstract
Implantation of adult human mesenchymal stem cells (MSCs) to treat neural disorders shows promise. Depending on their microenvironment, MSCs could potentially be used for the repair and/or replacement of neurons in traumatic brain injury or the treatment of Parkinson's disease. This cross-disciplinary review incorporates aspects of neuroscience, stem cell biology, cancer biology and immunology to discuss interactions between inflammatory mediators and MSCs. We first discuss the role of microRNAs (miRNAs) in neurological development. Secondly, we discuss the ability of MSCs to transdifferentiate into functional neurons, which are regulated by miRNAs, and the implications of these cells for the therapy of neuropathological states. The administration of effective and safe MSC therapy must acknowledge immune mediators that may predispose the early differentiating MSCs to oncogenic insults. Thus, we discuss a key gene, RE-1 silencing transcription factor (REST), based on its dual role in neurogenesis and cancer development. Immune mediators could be central to MSC responses within a region of tissue injury and are also discussed in detail. Exploring the predisposition of MSCs to oncogenesis is critical for translational science since the implementation of safeguarding measures prior to therapy can lead to the successful delivery of stem cells to patients. The method by which MSCs could be applied for future therapies might require trans-disciplinary approaches for personalized treatments.
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Affiliation(s)
- P K Lim
- Department of Medicine-Division of Hematology/Oncology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA
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Patel DB, Patel NJ, Patel SK, Prajapati AM, Patel SA. RP-HPLC Method for the Estimation of Dutasteride in Tablet Dosage Form. Indian J Pharm Sci 2010; 72:113-6. [PMID: 20582201 PMCID: PMC2883211 DOI: 10.4103/0250-474x.62247] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 09/15/2009] [Accepted: 01/06/2010] [Indexed: 11/17/2022] Open
Abstract
A simple, sensitive and precise RP-HPLC method was developed for the determination of dutasteride in tablet dosage form. The RP-HPLC separation was achieved on phenomenex C18 column (250 mm, id 4.6 mm, 5 μm) using mobile phase methanol:water (90:10 v/v) at a flow rate of 1 ml/min at an ambient temperature. Quantification was achieved with photodiode array detection at 235 nm over the concentration range 1-12 μg/ml. The method was validated statistically and was applied successfully for the determination of dutasteride in tablets.
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Affiliation(s)
- Dipti B Patel
- S. K. Patel College of Pharmaceutical Education & Research, Department of Pharmaceutical Chemistry, Ganpat University, Kherva-382 711, India
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Patel SA, Patel PU, Patel NJ, Patel MM, Bangoriya UV. High performance thin layer chromatographic method for estimation of linezolid in tablets. Indian J Pharm Sci 2007. [DOI: 10.4103/0250-474x.36948] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Kharfan-Dabaja MA, Patel SA, Osunkoya AO, Kojouri K, Kamble R, Yang J, Hashmi M, Ozer H, Selby GB. Expression of the vascular endothelial growth factor receptors 1 and 2 in acute myeloid leukemia: incidence and feasibility of immunohistochemical staining. ACTA ACUST UNITED AC 2006; 28:254-8. [PMID: 16898965 DOI: 10.1111/j.1365-2257.2006.00802.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Vascular endothelial growth factor (VEGF) and its receptor tyrosine kinases, VEGFR-1 and VEGFR-2, are important therapeutic targets for various cancers including AML. Paraffin-embedded bone marrow samples (PE-BM) are, in most cases, the only tissue accessible to perform retrospective analyses of novel targets such as VEGF and/or its receptors. As a result, it limits our options to immunohistochemistry (IHS), or more expensive and less practical techniques such as enzyme-linked immunosorbent assay (ELISA) or fluorescence in situ hybridization (FISH). We analyzed the feasibility of IHS to measure VEGFR-1 and VEGFR-2 expression in 28 AML samples using monoclonal antibodies (moAbs) against Flt-1 (VEGFR-1) and KDR/Flk-1 (VEGFR-2). Medical records were reviewed for relevant clinical information. Expression of VEGFR-1 (+) and VEGFR-2 (+) were seen in 25% (7/28) and 43% (12/28) respectively. Forty-six percent (13/28) were dual-negatives for VEGFR-1 and VEGFR-2; 14% (4/28) were dual-positives for VEGFR-1 and VEGFR-2. An inferior survival was observed in patients whose myeloblasts express either VEGFR-1 (+) or VEGFR-2 (+), or both. Determination of expression of VEGF receptors (1 and 2) by IHS in PE-BM tissue is feasible. Prospective comparison of IHC to flow cytometry or other molecular techniques, and assessment of the prognostic significance of VEGF receptors in AML patients is warranted.
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Affiliation(s)
- M A Kharfan-Dabaja
- Section of Hematology-Oncology and OU cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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Patel SA, Patel CN, Patel MM. Visible spectrophotometric methods for the estimation of metoclopramide hydrochloride in tablets. Indian J Pharm Sci 2006. [DOI: 10.4103/0250-474x.26663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Patel SA, Patel NM, Patel MM. Spectrophotometric estimation of cefotaxime and ceftriaxone in pharmaceutical dosage forms. Indian J Pharm Sci 2006. [DOI: 10.4103/0250-474x.22977] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Patel SA, Luketich JD, Landreneau RP, Sciurba FC. Clinical trials in lung volume reduction surgery. Semin Thorac Cardiovasc Surg 2004; 15:464-71. [PMID: 14710389 DOI: 10.1053/j.semtcvs.2003.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S A Patel
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, PA 15213, USA
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Affiliation(s)
- S A Patel
- Department of Surgery, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY, USA
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Brophy DP, Patel SA. Optimal digital subtraction angiography of dorsalis pedis artery: effect of foot positioning on angiographic demonstration. J Vasc Interv Radiol 1999; 10:376-7. [PMID: 10102207 DOI: 10.1016/s1051-0443(99)70048-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Patel SA, Graunke DM, Pieper RO. Aberrant silencing of the CpG island-containing human O6-methylguanine DNA methyltransferase gene is associated with the loss of nucleosome-like positioning. Mol Cell Biol 1997; 17:5813-22. [PMID: 9315639 PMCID: PMC232429 DOI: 10.1128/mcb.17.10.5813] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Tumor-associated aberrant silencing of CpG island-containing genes has been correlated with increased cytosine methylation, a "closed" chromatin structure, and exclusion of transcription factor binding in the CpG island/promoter regions of affected genes. Given the lack of understanding of what constitutes a closed chromatin structure in CpG islands, however, it has been difficult to assess the relationship among cytosine methylation, chromatin structure, and inappropriate gene silencing. In this study, nuclease accessibility analysis was used to more clearly define the chromatin structure in the CpG island of the human O6-methylguanine DNA methyltransferase (MGMT) gene. Chromatin structure was then related to in vivo DNA-protein interactions and cytosine methylation status of the MGMT CpG island in human glioma cells varying in MGMT expression. The results of these studies indicated that the "open" chromatin structure associated with the MGMT CpG island in MGMT+ cells consisted of an approximately 250-bp transcription factor-binding, nuclease-accessible, nucleosome-free region of DNA, whose formation was associated with at least four flanking, precisely positioned nucleosome-like structures. In MGMT- cells, this precise nucleosomal array was lost and was replaced by randomly positioned nucleosomes (i.e., the closed chromatin structure), regardless of whether methylation of the CpG island was spread over the entire island or limited to regions outside the transcription factor binding region. These results suggest that CpG islands facilitate the expression of housekeeping genes by facilitating nucleosomal positioning and that the conditions that alter the formation of this array (such as perhaps methylation) may indirectly affect CpG island-containing gene expression.
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Affiliation(s)
- S A Patel
- Program in Molecular Biology and Division of Hematology/Oncology, Loyola University Chicago, Maywood, Illinois 60153, USA
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Ji Z, Hadac EM, Henne RM, Patel SA, Lybrand TP, Miller LJ. Direct identification of a distinct site of interaction between the carboxyl-terminal residue of cholecystokinin and the type A cholecystokinin receptor using photoaffinity labeling. J Biol Chem 1997; 272:24393-401. [PMID: 9305898 DOI: 10.1074/jbc.272.39.24393] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Mechanisms of ligand binding and activation of G protein-coupled receptors are particularly important, due to their ubiquitous expression and potential as drug targets. Molecular interactions between ligands and these receptors are best defined for small molecule ligands that bind within the transmembrane helices. Extracellular domains seem to be more important for peptide ligands, based largely on effects of receptor mutagenesis, where interference with binding or activity can reflect allosteric as well as direct effects. We now take the more direct approach of photoaffinity labeling the active site of the cholecystokinin (CCK) receptor, using a photolabile analogue of CCK having a blocked amino terminus. This probe, 125I-desaminotyrosyl-Gly-[Nle28,31, pNO2-Phe33]CCK-(26-33), binds specifically, saturably, and with high affinity (Ki = 3.3 nM) and has full agonist activity. This makes likely its being sited in a natural position within the receptor. As substrate, we used CHO-CCK receptor cells overexpressing functional recombinant rat type A CCK receptor. Covalent labeling of the appropriate Mr = 85,000-95,000 plasma membrane glycoprotein with core of Mr = 42,000 was established by SDS-polyacrylamide gel electrophoresis and autoradiography. A single domain adjacent to transmembrane 1 was labeled, as established by cyanogen bromide cleavage and separation by gel and/or high pressure liquid chromatography. The site of interaction was further defined by additional proteolysis with trypsin, with purification of the labeled fragment, followed by manual Edman degradation and radiochemical sequencing. This demonstrated that Trp39 was specifically labeled and likely resides proximate to the carboxyl-terminal pNO2-Phe33 residue of the probe. A model of this ligand-bound receptor has been constructed and will be used to plan future experiments to refine our understanding of this interaction.
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Affiliation(s)
- Z Ji
- Center for Basic Research in Digestive Diseases, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA
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Affiliation(s)
- C A Owens
- Department of Radiology, University of Illinois Medical Center, Chicago 60612, USA
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Ravindra R, McIlroy PJ, Patel SA. Drugs that influence tubulin polymerization modulate thyrotropin-releasing hormone receptor number in AtT-20 cells. Pharmacol Toxicol 1997; 80:24-9. [PMID: 9148278 DOI: 10.1111/j.1600-0773.1997.tb00279.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In order to examine the role of cytoskeleton in modulating the cell surface receptors, AtT-20 cells (stably expressing thyrotropin-releasing hormone receptors) were incubated with drugs that are known to modify the tubulin-microtubule system. The binding of [3H]methyl thyrotropin-releasing hormone ([3H]mTRH) to intact cells increased as a function of time, and was linear from 1.25 x 10(6) to 6.25 x 10(6) cells/ml. Cells incubated with colchicine, vinblastine, and taxol for 16 hr were harvested and the cell concentration was determined using a haemocytometer. Because the drugs inhibited the cell proliferation at 100 nM, it was decided to examine the effect of 100 nM of each of the three drugs on the ability of [3H]mTRH to bind cell surface receptors. Cells were incubated with the drugs for 16 hr at 37 degrees. After the incubation, cells (5 x 10(6) cells/ml) from each group were assayed for [3H]mTRH binding. Colchicine, vinblastine, and taxol stimulated [3H]mTRH binding by up to 27, 27, and 21%, respectively, without altering the Ka of the ligand to the receptor. These results suggest that perturbation of cytosolic microtubules leads to a reorganization of the spatial location of hormone receptors.
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Affiliation(s)
- R Ravindra
- Veterans Affairs Medical Center, North Chicago, IL 60064, USA
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37
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Sinha A, Clatch RJ, Stuck G, Blumenthal SA, Patel SA. Isoflurane hepatotoxicity: a case report and review of the literature. Am J Gastroenterol 1996; 91:2406-9. [PMID: 8931426] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Isoflurane, hailed as the anesthetic of the 1980s, is less hepatotoxic than its predecessors, halothane and enflurane. Since its release by the Food and Drug Administration in 1979, controversy has existed about the extent to which isoflurane is capable of producing hepatotoxic effects. In this report, we provide direct evidence that isoflurane can induce liver injury and should therefore be considered as a potential cause of serum transaminase elevations in any patient who is exposed to this anesthetic.
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Affiliation(s)
- A Sinha
- Department of Family Practice, Christ Hospital and Medical Center, Oak Lawn, Illinois, USA
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Abstract
In order to study Gq-tubulin interaction in the cytosol, GH3 and AtT-20 cells (stably expressing TRH receptor) were transiently transfected with Gq alpha cDNA. Forty-eight hours after transfection, thyrotropin-releasing hormone (TRH)-stimulated prolactin (PRL) secretion by Gq alpha-transfected GH3 cells increased by 90% compared to mock-transfected cells. In addition, using immunocytochemistry it was observed that Gq alpha-specific staining was much more prominent in Gq alpha-transfected GH3 and AtT-20 cells (also transfected with Gq alpha) compared to mock-transfected cells. Thus, transfection resulted in successful overexpression of functional Gq alpha. Forty-eight hours after transfection, cells were processed to obtain soluble and polymerized tubulin fractions. Tubulin levels were determined in these fractions by immunoblotting using polyclonal anti-tubulin antibodies. Compared to mock-transfected cells soluble tubulin levels decreased in Gq alpha-transfected GH3 and AtT-20 cells, by 33 and 52%, respectively. Moreover, compared to mock-transfected cells a 50% reduction in the ratio (an index of the flux between tubulin pools) of soluble and polymerized tubulin levels was observed in Gq alpha-transfected GH3 and AtT-20 cells. To determine whether these effects on tubulin were mediated by Gq directly, we examined the influence of purified Gq on tubulin polymerization. Gq (0.5 microM) inhibited polymerization of crude tubulin (present in GH3 cell cytosol) by 53%. In contrast to its effects on GH3 cell cytosol tubulin, Gq stimulated purified tubulin polymerization by 160%. These results suggest that Gq modulates the polymerization and depolymerization cycles of tubulin and that this modulation is in turn influenced by other unknown cellular components.
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Affiliation(s)
- R Ravindra
- Department of Cell and Molecular Biology, University of Medicine and Dentistry of New Jersey-School of Osteopathic Medicine, Stratford 08084, USA
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Ravindra R, Forman LJ, Patel SA. Effect of colchicine and taxol on thyrotropin-releasing hormone receptor coupling to G protein in GH(3) cells. Endocrine 1996; 4:43-52. [PMID: 21153290 DOI: 10.1007/bf02738873] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/1995] [Revised: 11/07/1995] [Accepted: 11/20/1995] [Indexed: 11/25/2022]
Abstract
The role of membrane-associated tubulin in TRH receptor-G protein coupling was investigated with the use of compounds that influence tubulin function. TRH-stimulated G protein GTPase activity in GH(3) cell membranes was used to determine receptor-G protein coupling. TRH-stimulated GTPase activity was abolished by G(qα) antibody, suggesting that TRH receptor coupling to G(q) results in the activation of G(qα) and the subsequent hydrolysis of GTP. TRH (1 μM) stimulated the enzymatic activity by up to 69 pmol/min/mg protein, and in the presence of 1 μM colchicine the hormone-stimulated activity was only 26 pmol/min/mg protein. Similar inhibition of TRH receptor-G protein coupling was observed with tubulin antibodies and purified tubulin, suggesting that perturbation of membrane-associated tubulin and/or tubulin-G protein interaction by these compounds disrupts receptor-G protein interaction. Next, the events occurring at the initial stages of TRH-mediated signal transduction were correlated to prolactin (PRL) secretion in GH(3) cells. Colchicine (1 μM) and taxol (1 μM) inhibited the basal PRL secretion by 38 and 44%, respectively. In addition, colchicine (1 μM) and taxol (1 μM) significantly inhibited TRH-stimulated PRL secretion. TRH-stimulated PRL secretion in control, colchicine-, and taxol-treated cells was 13.9, 9.1, and 6 ng/mL, respectively. Furthermore, polymerized tubulin levels were decreased by colchicine and increased by taxol. These results suggest that perturbation of the steady state of tubulin-G(q) interaction may disrupt the initial events in TRH-mediated signal transduction.
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Affiliation(s)
- R Ravindra
- Department of Cell Biology, University of Medicine and Dentistry of New Jersey-School of Osteopathic Medicine, Stratford, NJ
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Abstract
Esophageal variceal ligation (EVL) has emerged as a popular alternative to endoscopic sclerotherapy (ES), with equal efficacy as ES in control of active bleeding, rebleeding rate, and variceal eradication. The complication rate for EVL has been reported lower than for ES in several clinical trials. However, several unique complications inherent to EVL have been recognized. Overtube injury to the pharynx and proximal esophagus has been the most serious complication. Transient vocal cord paralysis, cricopharyngeal perforation, proximal esophageal laceration, varix rupture, and free esophageal perforation have also been reported. Direct banding-induced complications have been limited to rebleeding from banded ulcers, transient esophageal obstruction, and simple strictures. Pulmonary as well as serious systemic complications have yet to be reported. We report four complications of EVL, review the literature, and suggest strategies for the recognition, management, and prevention of EVL complications.
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Affiliation(s)
- W H Holderman
- Department of Medicine, University of Illinois at Chicago, USA
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Ravindra R, Forman LJ, Patel SA. Vinblastine and nocodazole inhibit basal and thyrotropin-releasing hormone-stimulated prolactin secretion in GH(3) cells. Endocrine 1995; 3:591-6. [PMID: 21153137 DOI: 10.1007/bf02953024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/1995] [Accepted: 04/20/1995] [Indexed: 11/27/2022]
Abstract
To investigate the efficacy of vinblastine as a possible therapeutic agent in prolactinomas, we have examined the effects of vinblastine on GH(3) cell function. The effects of vinblastine were compared to another anti-microtubule drug, nocodazole. At 24 h, prolactin (PRL) secretion was 737±63 ng/ml in control cells. In cells treated with 0.1, 1 and 10μM: nocodazole for 24 h, PRL secretion was reduced to 200±30 ng/ml. After a 24 h incubation with the drugs, cells were washed with drug-free medium and challenged with 100NM: TRH for 10 min. TRH-stimulated PRL secretion was 35±7 ng/ml in control cells, 14±0.5 ng/ml in vinblastine-treated cells and 8.8±0.1 ng/ml in nocodazole-treated cells. [(3)H]TRH binding to GH(3) cell membrane was inhibited by about 15% by vinblastine and nocodazole. In vinblastine and nocodazole treated cells, polymerized tubulin levels decreased by 46 and 55%, respectively. These observations that vinblastine suppresses PRL secretion by GH(3) cells suggest that this drug might be useful as a therapeutic agent for prolactinomas.
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Affiliation(s)
- R Ravindra
- Department of Cell Biology, University of Medicine and Dentistry of New Jersey-School of Osteopathic Medicine, 08084, Stratford, New Jersey, USA
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Abstract
The effect of thyrotropin-releasing hormone (TRH) on the tubulin-microtubule system in GH3 cells was investigated. Prolactin (PRL) secretion by GH3 cells was stimulated by TRH at 1, 5, and 10 min of incubation. The polymerized tubulin levels increased from 0.4 units micrograms-1 protein in control cells to 0.6 units micrograms-1 protein in cells incubated with TRH for 1 min. Soluble tubulin levels increased from 0.8 units microgram-1 protein in control cells to 1.2 units micrograms-1 protein in cells exposed to TRH for 5 min. Tubulin levels were similar in control cells and cells treated with TRH for 10 min. These results suggest that TRH-stimulated PRL secretion is accompanied by a shift in the equilibrium between tubulin pools.
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Affiliation(s)
- R Ravindra
- Department of Cell Biology, University of Medicine and Dentistry of New Jersey, School of Osteopathic Medicine, Stratford 08084, USA
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Abstract
Plasma membranes from anterior pituitary lobes of rats and GH3 cells were exposed to monoclonal anti-beta tubulin antibodies or normal mouse IgG, and treated with FITC-labeled anti-mouse IgG. Specimens were visualized with a microscope equipped with epifluorescence optics. Tubulin-specific fluorescence was very prominent in membranes incubated with tubulin antibody and was negligible in membranes incubated with normal mouse IgG or FITC-labeled anti-mouse IgG alone. Two dimensional electrophoresis revealed that 27% of the rat pituitary tubulin is beta-tubulin and 73% is alpha-tubulin; 17% of the GH3 cell tubulin is beta-tubulin and 83% is alpha-tubulin. These results suggest that tubulin is a component of plasma membranes of the rat pituitary and GH3 cells.
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Affiliation(s)
- R Ravindra
- Department of Cell Biology, UMDNJ-School of Osteopathic Medicine, Stratford 08084
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Patel SA, al-Haddadin D, Schopp J, Cantave I, Duarte B, Watkins JL. Gastrointestinal manifestations of amyloidosis: a case of diverticular perforation. Am J Gastroenterol 1993; 88:578-82. [PMID: 8470641] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Amyloidosis is an intriguing disorder. Its clinical presentation usually rests on the organ(s) infiltrated with the amyloid. We report a patient who presented with peritonitis secondary to a perforated large jejunal diverticulum and multiple small bowel diverticula. We believe the diverticula were a direct result of primary amyloid infiltration of the intestine in the antimesenteric location. This is the first reported case of small bowel diverticula caused by amyloidosis.
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Affiliation(s)
- S A Patel
- Section of Digestive and Liver Diseases, University of Illinois, Chicago
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Patel SA, Castillo DF, Hibbeln JF, Watkins JL. Magnetic resonance imaging appearance of hepatic schistosomiasis, with ultrasound and computed tomography correlation. Am J Gastroenterol 1993; 88:113-6. [PMID: 8420249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- S A Patel
- Department of Internal Medicine, University of Illinois, Chicago
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Calvin HI, von Hagen S, Hess JL, Patel SA, Fu SC. Lens GSH depletion and electrolyte changes preceding cataracts induced by buthionine sulfoximine in suckling mice. Exp Eye Res 1992; 54:621-6. [PMID: 1623947 DOI: 10.1016/0014-4835(92)90141-e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cataracts were induced in suckling mice by multiple injections of L-buthionine-S,R-sulfoximine (BSO), a specific inhibitor of GSH biosynthesis, starting on post-natal day 7. The earliest visible lens aberrations began approximately 2 days after t(o), following 99% depletion of lens GSH. Cataract development then proceeded through four stages within less than 24 hr. Elevated Na+ and Ca+ and decreased K+ were first detected in pre-cataractous (stage 0) lenses. During stage 0, lens Na+ and K+ levels displayed a significant inverse correlation; by contrast, Ca2+ levels were poorly correlated with those of Na+. The initial increase in Na+ exceeded the decrease in K+. This suggested the presence of osmotic stress prior to cataract stage 1 (developing floriform). Increased lens hydration was first apparent in stage 1, coincident with a marked elevation of Ca2+, further increase in Na+ and decrease in K+. These trends persisted in the stage 2 cataract (completed floriform). Subsequent changes in lens hydration and cation content during cataract stages 3 (degenerate floriform) and 4 (amorphous translucent) suggested substantial influx of extracellular fluid into the affected lenses. The BSO cataract may represent a useful in vivo model to study the functions of GSH in maintaining normal lens cation balance and transparency.
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Affiliation(s)
- H I Calvin
- Department of Ophthalmology, Biochemistry and Molecular Biology, UMD-NJ Medical School, Newark 07103
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Abstract
L-buthionine-S,R-sulfoximine (BSO), a specific inhibitor of GSH biosynthesis, was administered four times daily to mouse pups on post-natal days 7 and 8, inducing initiation of opacification on day 9. The initial progression of the cataract (less than 24 hr) was divided into four stages: (1) developing floriform; (2) mature floriform; (3) degenerate floriform; and (4) amorphous translucent cataract. Following this, dense corticonuclear opacities developed within several days. Two-dimensional gel electrophoresis of water-soluble whole lens extracts indicated that the most rapid early cataractous changes, occurring mainly during stage 2, were loss of the two major components of the heavy beta-crystallin fraction, a 31-kDa basic polypeptide and an acidic component at 27 kDa, concomitant with the appearance of new species at 30 and 25 kDa. This was followed by more extensive modification of both alpha and beta-crystallins during stages 3 and 4 and the appearance of abnormal species at 26, 19 and 18 kDa, which were slightly more acidic than the major normal alpha A-crystallin polypeptide. The gamma-crystallin components, relatively unaffected at stage 4, were then lost rapidly as dense opacities ensued. By contrast with the water-soluble fraction, the normal day 9 urea-soluble fraction was deficient in gamma-crystallin polypeptides and enriched in anodic components whose relative electrophoretic mobilities were similar to those reported previously for phosphorylated bovine alpha A-crystallin and several cytoskeletal polypeptides. At stage 4 of the cataract, the modifications of normal alpha and beta-crystallin components in the urea-soluble fraction paralleled those in the water-soluble fraction, but the products seen were more numerous. In addition, the cytoskeletal proteins were no longer detectable. Substantial increases in lens Ca2+ that precede all of the above changes in lens polypeptide composition suggest that Ca(2+)-activated proteolysis may play a major role in development of BSO cataracts.
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Affiliation(s)
- H I Calvin
- Department of Ophthalmology, UMD-NJ Medical School, Newark 07103
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Patel SA, Borges MC, Batt MD, Rosenblate HJ. Trichosporon cholangitis associated with hyperbilirubinemia, and findings suggesting primary sclerosing cholangitis on endoscopic retrograde cholangiopancreatography. Am J Gastroenterol 1990; 85:84-7. [PMID: 2296969] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Usually, ascending cholangitis is a bacterial process. However, in the debilitated or immunocompromised patient, mycotic cholangitis must be placed in the differential diagnosis. We report a patient with cryptogenic cirrhosis whose presenting problem in his terminal hospitalization was spontaneous bacterial peritonitis, for which he was treated with broad-spectrum antibiotics. Endoscopic retrograde cholangiopancreatogram was performed during the hospital course to explain his profound hyperbilirubinemia. The findings were grossly consistent with primary sclerosing cholangitis or cholangiocarcinoma. The patient subsequently continued to deteriorate, and died with hepatic and renal failure. At autopsy, he was found to have choledocholithiasis, marked biliary duct proliferation, and ascending cholangitis, with Trichosporon demonstrated histologically to be invading the bile ducts. To our knowledge, this is the first reported case of Trichosporon cholangitis.
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Affiliation(s)
- S A Patel
- Lutheran General Hospital, Park Ridge, Illinois
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Abstract
This paper reviews the role of colonoscopy in large-bowel obstruction by a gallstone. We report the case of an elderly female with a cholecystocolonic fistula who had a large-bowel obstruction caused by a gallstone that migrated to the level of narrowing in the large bowel. After multiple attempts at removal of the stone with a snare and basket retriever, the patient was taken to the operating room and the stone was removed. Colonscopy in these circumstances can be diagnostic and possibly therapeutic.
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Affiliation(s)
- S A Patel
- Lutheran General Hospital, Department of Internal Medicine, Park Ridge
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Patel SA, Braun HL, Fine MS, Moody ML. Imipenem-associated elevation of amylase and lipase. Am J Gastroenterol 1989; 84:80-1. [PMID: 2463756] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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