[A retrospective analysis of clinical characteristics and prognostic factors for 152 cases of Staphylococcus aureus bloodstream infection]

To understand the clinical characteristics of Staphylococcus aureus bloodstream infection and the main risk factors affecting clinical prognosis, providing a reference for clinical prevention and control of Staphylococcus aureus bloodstream infection. In this study, the clinical data of 152 patients with Staphylococcus aureus bloodstream infection admitted to Guangdong Provincial People's Hospital from January 2019 to December 2021 were retrospectively analyzed by reviewing the electronic medical record system, including underlying diseases, clinical characteristics, risk factors, and bacterial resistance. Statistical methods such as Chi-Squared Test and t Test were used to analyze the related risk factors that may affect the clinical characteristics and prognosis of patients with Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection, then the variables with P<0.05 in univariate analysis were included in the multivariate logistic regression model to analyze the independent risk factors of poor prognosis. The results showed among 152 patients with Staphylococcus aureus bloodstream infection, 50 patients (32.89%) were infected with MRSA. In comparison, 102 patients (67.11%) were infected with methicillin-sensitive Staphylococcus aureus (MSSA). Except for rifampicin, the resistance rate of MRSA to commonly used antibiotics was all higher than that of MSSA, and the difference was statistically significant (Chi-square values were 8.272, 11.972, 4.998, 4.776, respectively;all P-values are less than 0.05). Strains resistant to vancomycin, linezolid, and quinupristin/dalfopristin were not found. In the MRSA group, indwelling catheter and drainage tube, carbapenems, and β-lactamase inhibitor treatment were significantly higher than the MSSA group. The difference was statistically significant (P<0.05). The incidence of poor prognosis of bloodstream infection in the MRSA group was higher than that in the MSSA group (34.00% vs 13.73%), and the difference was statistically significant (χ²=8.495, P<0.05). No independent risk factors associated with poor prognosis were found in the included patients with MRSA bloodstream infection.Multivariate Logistic regression model analysis showed that solid malignant tumors (OR=13.576, 95%CI: 3.352-54.977, P<0.05), mechanical ventilation (OR=7.468, 95%CI: 1.398-39.884, P<0.05) were the most important independent risk factors for poor prognosis in patients with Staphylococcus aureus bloodstream infection. In summary, the poor prognosis rate of MRSA bloodstream infection is higher than that of MSSA. The clinical evaluation of related risk factors should be strengthened, targeted prevention and control interventions should be taken to improve the prognosis of patients with Staphylococcus aureus bloodstream infection, and the use of antibiotics should be rational and standardized, to control bacterial infection and drug resistance effectively.

Nirmatrelvir increases blood tacrolimus concentration in COVID-19 patients as determined by UHPLC-MS/MS method

OBJECTIVE

Transplant recipients have a higher risk of SARS-CoV-2 infection owing to the use of immunosuppressive drugs like tacrolimus (FK506). FK506 and nirmatrelvir (NMV) (an anti-SARS-CoV-2 drug) are metabolized by cytochrome P450 3A4 and may have potential drug-drug interactions. It is important to determine the effect of NMV on FK506 concentrations.

PATIENTS AND METHODS

Following protein precipitation from blood, FK506 and its internal standard (FK506-13C,2d4) were detected by ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS). Total 22 blood samples (valley concentrations) from two coronavirus disease 2019 (COVID-19) patients were collected and analyzed for FK506 concentrations.

RESULTS

Blood levels of FK506 (0.5-100 ng/mL) showed good linearity. The UHPLC-MS/MS method was validated with intra- and inter-batch accuracies of 104.55-107.85%, and 99.52-108.01%, respectively, and precisions of < 15%. Mean blood FK506 concentration was 12.01 ng/mL (range, 3.15-33.1 ng/mL). Five-day co-administration with NMV increased the FK506 concentrations from 3.15 ng/mL to 33.1 ng/mL, returning to 3.36 ng/mL after a 9-day-washout.

CONCLUSIONS

We developed a simple quantification method for therapeutic drug monitoring of FK506 in patients with COVID-19 using UHPLC-MS/MS with protein precipitation. We found that NMV increased FK506 blood concentration 10-fold. Therefore, it is necessary to re-consider co-administration of FK506 with NMV.

[Analysis of liver function injury associated with 2019-nCoV Omicron mutant strains]

Objective: To investigate the clinical features and influencing factors of liver function injury in patients with 2019-nCoV/SARS-CoV-2 Omicron mutant strains. Methods: 1 183 confirmed imported cases of SARS-CoV-2 who were admitted at Shanghai Public Health Clinical Center (affiliated to Fudan University) from July 1, 2021 to January 15, 2022 were collected. Clinical data, viral genotyping and laboratory test results were collected to retrospectively analyze the basic condition and clinical characteristics of liver function injury. Statistical analysis was performed using t-test or Wilcoxon rank-sum test, χ² test or Fisher's exact test, Pearson correlation test and logistic regression analysis. Results: 125 (10.6%) cases had raised baseline ALT level and 60 (5.1%) cases had abnormal baseline AST level. Among them, 33 cases (2.8%) had received hepatoprotective drugs. Liver function injury was generally mild in SARS-CoV-2 infection and minimal in Omicron mutant strains. Leukocyte count was increased in patients with raised alanine aminotransferase (ALT) [(6.96±1.78)×10⁹/L vs. (6.41±1.96)×10⁹/L, P=0.005 2], CT scan showed the proportion of liver hypodensity was significantly increased (2.4% vs. 0.3%, P=0.018 0). High-sensitivity C-reactive protein [(7.83±22.36) mg/L vs. (2.68±6.21) mg/L, P=0.007 8] and D-dimer [(0.34±0.39) μg/ml vs. (0.31±0.75) μg/ml, P=0.047 5] levels were higher in patients with raised AST than normal group. 26 cases had normal liver function at hospital admission; however, abnormal liver function was occurred during the course of the disease. Another 8 patients had abnormal liver function at hospital admission, and reduced liver function further during the course of treatment. Recovery time and length of hospital stay was significantly affected in patients with worsened liver function. Baseline body mass index value [odds ratio (OR)]=1.80, P=0.047), non-Omicron strains (OR=12.63, P=0.046), D-dimer (OR=2.36, P=0.047) and interleukin-6 levels (OR=1.03, P=0.009), and those who used glucocorticoids and/or ulinastatin after hospital admission (OR=6.89, P=0.034) had a higher risk of worsening liver function. Conclusions: Liver dysfunction could be observed among COVID-19 patients. Patients infected with omicron variant generally showed mild liver injury. Dynamic monitoring of liver function is necessary, especially among those with baseline elevated IL-6, D-Dimer level and use of antiinflammation medication during treatment.

Wernekinck Commissure Syndrome with Holmes Tremor: A Report of Two Cases and Review of Literature

Wernekinck commissure syndrome is a rare midbrain infarction, it consists of several symptoms including bilateral cerebellar ataxia, ophthalmoplegia, and palatal tremor. Holmes tremor is a rare clinical syndrome characterized by a combination of resting, postural, and action tremors. We describe two cases of Wernekinck commissure syndrome with Holmes tremor. To the best of our knowledge, it has been rarely reported in the literature to date. Both of the cases were presented with acute onset of bilateral cerebellar ataxia, dysarthria, and Holmes tremor. In the treatment, one patient was given "clonazepam and benheisol," the other was received acupuncture therapy, both of them showed a marked improvement in ataxia and tremor.

11-year follow-up outcomes of catheter ablation of para-hisian accessory pathways

Funding Acknowledgements

Type of funding sources: None.

Background

Ablation of para-hisian accessory pathways (APs) remains challenging due to anatomic characteristics and few studies have focused on the causes for recurrence of radiofrequency ablation of para-hisian APs.

Objective

This retrospective single center study was aimed to explore the risk factors for recurrence of para-hisian APs.

Methods

113 patients who had a para-hisian AP with an acute success were enrolled in the study. In the 11-year follow-up, 15 cases had a recurrent para-hisian AP. Therefore 98 patients were classified into success group while 15 patients were classified into recurrence group. Demographic and ablation characteristics were analyzed.

Results

Gender difference was similar in two groups. The median age was 36.2 years old and was younger in recurrence group. Maximum ablation power was significantly higher in success group (29 ± 7.5 vs 22.9 ± 7.8, p &lt; 0.01). Ablation time of final target sites was found to be markedly higher in success group (123.4 ± 53.1 vs 86.7 ± 58.3, p &lt; 0.05). Ablation time less than 60 seconds was detected in 12 (12.2%) cases in success group and 7 (46.7%) cases in recurrence group (p &lt; 0.01). Occurrence of junctional rhythm was significantly higher in recurrence group (25.5% vs 53.3%, p &lt; 0.05). No severe conduction block, no pacemaker implantation and no stroke were reported. Junctional rhythm during ablation (OR = 3.833, 95%CI 1.083-13.572, p = 0.037) and ablation time &lt;60s (OR = 5.487, 95%CI 1.411-21.340, p = 0.014) were independent risk factors for the recurrence of para-hisian AP.

Conclusions

Considering the long-term safety of ablation of para-hisian AP, proper extension of ablation time and increase of ablation power could be applied during operation.

[Histopathological features of squamous cell carcinoma of lung neoadjuvant immunotherapy focusing on responses]

Objective: To analyze the pathologic features of responses to neoadjuvant immunotherapy of squamous cell carcinoma (SCC) of the lung. Methods: The study included 31 patients with resected lung SCC post neoadjuvant immunotherapy. All patients were recruited from the neoadjuvant anti-PD-1 (Sintilimab) phase Ⅰb clinical trial (ChiCTR-OIC-17013726). The histopathological morphology and different degrees of pathologic response to immunotherapy were evaluated basing on irPRC standard. Results: According to the percentage of residual viable tumor (% RVT), pathologic responses of complete pathologic response (cPR), major pathologic response (MPR) and non-MPR were noted in 19% (n=6), 29% (n=9), and 52% (n=16) of patients respectively. In addition, extensive immune activation phenomena (immune cell infiltration, including infiltration of lymphocytes, plasma cells, foamy macrophages, lymphocyte aggregation and tertiary lymphoid structures formation) and tissue repair features (giant cells, granuloma formation, proliferative fibrosis and neovascularization) were observed in tumor regression bed. Conclusions: Neoadjuvant immunotherapy has favorable effect on lung SCC. Pathologic assessment of resected lung cancer specimens after neoadjuvant immunotherapy shows unique histopathological features consistent with its mechanism.

Assessment of Ischemic Volumes by Using Relative Filling Time Delay on CTP Source Image in Patients with Acute Stroke with Anterior Circulation Large Vessel Occlusions

BACKGROUND AND PURPOSE

Thrombectomy up to 24 hours after stroke onset in patients with specific ischemic brain volumes remains a challenge, because many stroke centers do not apply specialized software to calculate ischemic volumes at advanced imaging. We aimed to establish the association between relative filling time delay on CTP source imaging and ischemic volume parameters and the infarct penumbra to core volume mismatch in patients with acute ischemic stroke.

MATERIALS AND METHODS

Consecutive patients with acute ischemic stroke and with M1 segment MCA with or without terminal ICA occlusions on baseline CTA and CTP within 24 hours of stroke symptom onset were included. Ischemic volumes were analyzed with software based on CTP maps. Relative filling time delay was classified into 4 grades-grade 0: relative filling time delay = 0 seconds; grade 1: relative filling time delay >0 to ≤4 seconds; grade 2: relative filling time delay >4 to ≤8 seconds; and grade 3: relative filling time delay > 8 seconds. Differences in ischemic volume parameters among relative filling time delay grades were tested.

RESULTS

We recruited 138 patients (median age, 69 years; 62.3% male). Different median volumes of the infarct core (grade 0, 7.3 mL; grade 1, 23.3 mL; grade 2, 45.7 mL; grade 3, 135 mL [P < .001]) and the penumbra (grade 0, 47.6 mL; grade 1, 90 mL; grade 2, 110 mL; grade 3, 92 mL [P = .043]) were observed among relative filling time delay grades. Target mismatch (defined by the criteria of the DEFUSE 3 trial) was identified in 71.7% of the patients (99/138). A relative filling time delay grade ≤ 1 independently predicted target mismatch, with a sensitivity of 0.79 (95% CI, 0.7-0.87) and a specificity of 0.66 (95% CI, 0.49-0.8).

CONCLUSIONS

Relative filling time delay grade based on CTP source imaging is a simple and effective parameter for evaluating ischemic volumes and target mismatch in patients with acute ischemic stroke. Further studies that compare relative filling time delay grade with clinical functional outcomes are necessary.

MiR-24 alleviates cardiomyocyte apoptosis after myocardial infarction via targeting BIM

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "MiR-24 alleviates cardiomyocyte apoptosis after myocardial infarction via targeting BIM, by L.-J. Pan, X. Wang, Y. Ling, H. Gong, published in Eur Rev Med Pharmacol Sci 2017; 21 (13): 3088-3097-PMID: 28742197" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/13100.

[Analysis of baseline liver biochemical parameters in 324 cases with novel coronavirus pneumonia in Shanghai area]

Objective: To summarize the clinical characteristics and liver biochemical parameters of 324 cases admitted with novel coronavirus pneumonia in Shanghai area. Methods: Clinical data and baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia admitted to the Shanghai Public Health Clinical Center from January 20, 2020 to February 24, 2020 were retrospectively analyzed. Patients were divided into two groups based on the status of illness: mild type (mild and typical) and severe type (severe and critical).The differences in clinical data and baseline liver biochemical parameters of the two groups were described and compared. The t-test and Wilcoxon rank-sum test were used for measurement data. The enumeration data were expressed by frequency and rate, and chi-square test was used. Results: Of the 324 cases with novel coronavirus pneumonia, 26 were severe cases (8%), with median onset of 5 days, 20 cases were HBsAg positive (6.2%), and 70 cases (21.6%) with fatty liver, diagnosed with X-ray computed tomography. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyl transferase (GGT), total bilirubin (TBil), albumin(ALB) and international normalized ratio (INR) of 324 cases at baseline were 27.86 ± 20.02 U/L, 29.33 ± 21.02 U/L, 59.93 ± 18.96 U / L, 39.00 ± 54.44 U/L, 9.46 ± 4.58 μmol / L, 40.64 ± 4.13 g / L and 1.02 ± 0.10. Of which, ALT was > than the upper limit of normal (> ULN), accounting for 15.7% (51/324). ALT and AST > ULN, accounting for 10.5% (34/324). ALP > ULN, accounting for 1.2% (4/324). ALP and GGT > ULN, accounting for 0.9% (3/324). INR > ULN was lowest, accounting for 0.6% (2/324). There were no statistically significant differences (P > 0.05) in ALT [(21.5 vs. 26) U / L, P = 0.093], ALP [(57 vs.59) U/L, P = 0.674], and GGT [(24 vs.28) U/L, P = 0.101] between the severe group and the mild group. There were statistically significant differences in AST (23 U/L vs. 34 U/L, P < 0.01), TBil (10.75 vs. 8.05 μmol / L, P < 0.01), ALB (35.79 ± 4.75 vs. 41.07 ± 3.80 g/L, P < 0.01), and INR (1.00 vs. 1.04, P < 0.01). Conclusion: The baseline liver biochemical parameters of 324 cases with novel coronavirus pneumonia in Shanghai area was comparatively lower and the liverinjury degree was mild, and the bile duct cell damage was rare.

Determination of Glyphosate and Aminomethylphosphonic Acid in Crops by Capillary Gas Chromatography with Mass-Selective Detection: Collaborative Study

A collaborative study was conducted to validate a method for the determination of glyphosate and aminomethylphosphonic acid (AMPA) in crops. The analytes are extracted from crops with water, and the crude extracts are then subjected to a cation exchange cleanup. The analytes are derivatized by the direct addition of the aqueous extract into a mixture of heptafluorobutanol and trifluoroacetic anhydride. The derivatized analytes are quantitated by capillary gas chromatography with mass-selective detection (MSD). The collaborative study involved 13 laboratories located in 5 countries 12 laboratories returned valid data sets. The crops tested were field corn grain, soya forage, and walnut nutmeat at concentrations of 0.050, 0.40, and 2.0 mg/kg. The study used a split-level pair replication scheme with blindly coded laboratory samples. Twelve materials were analyzed, including 1 control and 3 split-level pairs for each matrix, 1 pair at each nominal concentration. For glyphosate, the mean recovery was 91%, the average intralaboratory variance, the repeatability relative standard deviation (RSDr), was 11%, and the interlaboratory variance, the reproducibility relative standard deviation (RSDR), was 16%. For AMPA, the mean recovery was 87%, the RSDr was 16%, and the RSDR was 25% at mg/kg levels.

Stromal fibroblast-derived MFAP5 promotes the invasion and migration of breast cancer cells via Notch1/slug signaling

BACKGROUND

The tumor microenvironment (TME) regulates tumor progression, and cancer-associated fibroblasts (CAFs) are the primary stromal components of the TME, with the potential to drive tumor metastasis via the secretion of paracrine factors, but the specific mechanisms driving this process have not been defined.

METHODS

Proteins secreted from CAFs and normal fibroblasts (NFs) were analyzed via proteomic analysis (fold change > 2, p < 0.05) to identify tumor-promoting proteins secreted by CAFs.

RESULTS

Proteomic analysis revealed that microfibrillar-associated protein 5 (MFAP5) is preferentially expressed and secreted by CAFs relative to NFs, which was confirmed by Western blotting and RT-qPCR. Transwell and wound healing assays confirmed that MFAP5 is secreted by CAFs, and drives the invasion and migration of MCF7 breast cancer cells. We further found that in MCF7 cells MFAP5 promoted epithelial-mesenchymal transition, activating Notch1 signaling and consequently upregulating NICD1 and slug. When Notch1 was knocked down in MCF7 cells, the ability of MFAP5 to promote invasion and migration decreased.

CONCLUSION

CAFs promote cancer cells invasion and migration via MFAP5 secretion and activation of the Notch1/slug signaling. These data highlight this pathway as a therapeutic target to disrupt tumor progression through the interference of CAF-tumor crosstalk.

Abstract P6-09-07: Expression of miR-106b in circulating tumor cells is associated with EMT and prognosis in metastatic breast cancer patients

# Co-first author: W.T., G.L., X.X.

* Co-Correspondence: C.G. and W.G.J.

Abstract

Background: Circulating tumor cells (CTCs) display changes in epithelial-mesenchymal transition (EMT) markers and miRNAs regulate EMT in breast cancer cells. The association between EMT characteristics and miRNA expression in CTCs of metastatic breast cancer (MBC) patients and their clinical implications remain unknown.

Methods: CTC-specific miRNAs were screened based on comparison of the miRNA profile between CTC and primary tumor. RT-PCR was used to quantity the expression levels of EMT makers and miRNA candidates. We enrolled 219 MBC patients with CTCs ≥ 5/7.5mL blood from 2 cohorts and CTCs were detected and enriched by CellSearch. Overall survival (OS) and radiological response were analyzed. CTCs were divided into epithelial- (E-CTCs) and mesenchymal-like CTC (M-CTCs) phenotypes based on a cut-off value derived from suspended breast cancer cells recovered from PBMCs.

Results: MiR-106b displayed upregulation in CTCs, with a higher level in M-CTCs than E-CTCs. Patients with E-CTCs showed better OS than those with M-CTCs (HR 1.77, 95% CI 1.14-2.78, P =0.012). CTCs from chemo-resistant MBC patients exhibited higher miR-106b. CTC-specific miR-106b was negatively associated with therapy response and OS (HR 1.73, 95% CI 1.06-2.84, P = 0.029).

Conclusions: CTC-specific miR-106b was associated with EMT phenotypes of CTCs and may predict prognosis in MBC patients.

Citation Format: Tan W, Liang G, Xie X, Tan L, Sanders AJ, Liu Z, Ling Y, Zhong W, Jiang WG, Gong C. Expression of miR-106b in circulating tumor cells is associated with EMT and prognosis in metastatic breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-09-07.

Abstract P2-08-56: Effects of young age on prognosis in patients with node-negative tumors 2 cm or smaller breast cancer

Background It is still controversial to consider age as a prognostic factor into the treatment strategy of patients with T1N0M0 breast cancer.

Aim The main purpose of this study was to evaluate the effect of age on recurrence risk in patients diagnosed with T1N0M0 breast cancer as well as compare the prognosis of young aged patients(YA,≤40 years old) to non-young aged patients(non-YA,&gt;40 years old) by using a propensity score matching(PSM) analysis.

Methods 365 patients with T1N0M0 breast cancer diagnosed between 2003 and 2016 who received surgery in Sun Yat-sen Memorial Hospital Breast Cancer Center were included.The recurrence free survival (RFS) and risk factors for recurrence were identified by using Kaplan-Meier method and Cox proportional hazards models. PSM was then used to reduce the confounding effect of known risk factors on prognosis and then to compare 5-year RFS rates in patients between two age groups.

Results After a median follow up of 79 months, 54 patients developed recurrences and 5-year RFS was 87.6%. YA patients had lower RFS estimates (80.6%), compared to patients diagnosed in a later age (89.1% if older than 40-years old; P = 0.049). YA patients tended to have Her-2 positive, TNBC tumors, higher rate of Ki-67 expression and nuclear grade tumor. At multivariate analysis, Her-2 positive (HR 2.115; 95% CI 1.103-4.055, p=0.024) and TNBC (HR 2.963; 95% CI 1.485-5.914, p=0.002) resulted independent prognostic factors of patient with T1N0M0 breast cancer. In the subgroup analysis, we found significant poor RFS for YA patients with Her-2 positive breast cancer compared to the older counterparts(p=0.006) and YA patients were associated with significantly higher rates of the locoregional recurrence rather than metastasis(p=0.004), especially in first 5 years after diagnosis. After PSM, the baseline level and treatment status including tumor size, grade, HR status, Her-2 status, Ki67 expression breast surgery type and systemic adjuvant treatment(AST) of patients in the two age groups tended to be equal. As result, we found significant difference in the 5-year RFS between two age groups(p=0.008).

Conclusion Based on equal treatment condition, young age at presentation conferred a worse prognosis in patients with T1N0M0 breast cancer is independent on other pathological features.

Citation Format: Zhong W, Tan L, You N, Wang Y, Liang G, Liu Z, Ling Y, Tian Z, Gong C. Effects of young age on prognosis in patients with node-negative tumors 2 cm or smaller breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-56.

Abstract P2-07-12: A prognostic prediction nomogram (PDIDC) for breast Paget's disease with infiltrating ductal carcinoma patients: A SEER cohort analysis

Purpose

The aim of the study was to develop a specific nomogram for prediction of prognosis for breast Paget's disease with infiltrating ductal carcinoma (PD-IDC) patients.

Patients and Methods

Patients data were obtained by the Surveillance, Epidemiology, and End Results (SEER) program (N=2502). Study outcome was Breast Cancer Specific Survival (BCSS). Cox proportional hazards model was applied to identify risk factors and develop predictive model. For internal validation, discrimination was calculated with the concordance index (C-index) using the bootstrap method and calibration assessed.

Results

NPI classification, skin symptom, tumor site and age showed significant association with BCSS(table.1)and were used to build the PDIDC nomogram and to calculate risk score. PDIDC nomogram's C-index (0.791, 95%CI 0.783-0.818) showed better discrimination power than NPI classification (0.691, 95%CI, 0.650-0.735, P= 0.000) and AJCC staging (0.718, 95%CI, 0.695-0.741, P=0.000). Patients were divided into high-risk (1882/2502, 75.21%) and low-risk (620/2502, 24.78%) subgroups with the optimal cut-off of risk scores (4.28). The total BCSS of low-risk subgroup was 77.8% (95%CI 74.4%-81.4%) vs. 31.1% (95%CI 19.4-49.8) of high-risk group (P=0.000). Bootstrap internal validation demonstrated an average C-index of 0.739 (95% CI, 0.692-0.746). The nomogram calibration was validated to be accurate in predicting 5-year and 10-year survival.

Variable finally selected for risk predicted model.PredictorHazard RatioP Value95% CINPI classification Good1 Moderate2.170.0001.51-3.14Poor7.260.0004.96-10.63Skin symptom Without1 With1.760.0001.34-2.32Tumor site Centrally located1 Non-centrally located1.250.0421.07-1.56Age*1.010.0001.01-1.03* Continuous variable.

Conclusion

Utilizing NPI classification, skin symptom, tumor site and age, we developed the PDIDC nomogram to predict the 5-year and 10-year BCSS of breast PD-IDC patients.

Citation Format: Tan L, Chen K, Jiang WG, You N, Wang Y, Sanders A, Liang G, Liu Z, Ling Y, Zhong W, Tian Z, Gong C. A prognostic prediction nomogram (PDIDC) for breast Paget's disease with infiltrating ductal carcinoma patients: A SEER cohort analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-12.

Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use

Tobacco and alcohol use are leading causes of mortality that influence risk for many complex diseases and disorders1. They are heritable2,3 and etiologically related4,5 behaviors that have been resistant to gene discovery efforts6-11. In sample sizes up to 1.2 million individuals, we discovered 566 genetic variants in 406 loci associated with multiple stages of tobacco use (initiation, cessation, and heaviness) as well as alcohol use, with 150 loci evidencing pleiotropic association. Smoking phenotypes were positively genetically correlated with many health conditions, whereas alcohol use was negatively correlated with these conditions, such that increased genetic risk for alcohol use is associated with lower disease risk. We report evidence for the involvement of many systems in tobacco and alcohol use, including genes involved in nicotinic, dopaminergic, and glutamatergic neurotransmission. The results provide a solid starting point to evaluate the effects of these loci in model organisms and more precise substance use measures.

Semi-dominant mutation in the cysteine-rich receptor-like kinase gene, ALS1, conducts constitutive defence response in rice

Plants have evolved a sophisticated two-branch defence system to prevent the growth and spread of pathogen infection. The novel Cys-rich repeat (CRR) containing receptor-like kinases, known as CRKs, were reported to mediate defence resistance in plants. For rice, there are only two reports of CRKs. A semi-dominant lesion mimic mutant als1 (apoptosis leaf and sheath 1) in rice was identified to demonstrate spontaneous lesions on the leaf blade and sheath. A map-based cloning strategy was used for fine mapping and cloning of ALS1, which was confirmed to be a typical CRK in rice. Functional studies of ALS1 were conducted, including phylogenetic analysis, expression analysis, subcellular location and blast resistance identification. Most pathogenesis-related (PR) genes and other defence-related genes were activated and up-regulated to a high degree. ALS1 was expressed mainly in the leaf blade and sheath, in which further study revealed that ALS1 was present in the vascular bundles. ALS1 was located in the cell membrane of rice protoplasts, and its mutation did not change its subcellular location. Jasmonic acid (JA) and salicylic acid (SA) accumulation were observed in als1, and enhanced blast resistance was also observed. The mutation of ALS1 caused a constitutively activated defence response in als1. The results of our study imply that ALS1 participates in a defence response resembling the common SA-, JA- and NH1-mediated defence responses in rice.

Reduced fibre size, capillary supply and mitochondrial activity in constitutional thinness' skeletal muscle

AIM

Constitutional thinness (CT) is a rare condition of natural low body weight, with no psychological issues, no marker of undernutrition and a resistance to weight gain. This study evaluated the skeletal muscle phenotype of CT women by comparison with a normal BMI control group.

METHODS

Ten CT women (BMI < 17.5 kg/m² ) and 10 female controls (BMI: 18.5-25 kg/m² ) underwent metabolic and hormonal assessment along with muscle biopsies to analyse the skeletal muscular fibres pattern, capillarity, enzymes activities and transcriptomics.

RESULTS

Constitutional thinness displayed similar energy balance metabolic and hormonal profile to controls. Constitutional thinness presented with lower mean area of all the skeletal muscular fibres (-24%, P = .01) and percentage of slow-twitch type I fibres (-25%, P = .02, respectively). Significant downregulation of the mRNA expression of several mitochondrial-related genes and triglycerides metabolism was found along with low cytochrome c oxidase (COX) activity and capillary network in type I fibres. Pre- and post-mitochondrial respiratory chain enzymes levels were found similar to controls. Transcriptomics also revealed downregulation of cytoskeletal-related genes.

CONCLUSION

Diminished type I fibres, decreased mitochondrial and metabolic activity suggested by these results are discordant with normal resting metabolic rate of CT subjects. Downregulated genes related to cytoskeletal proteins and myocyte differentiation could account for CT's resistance to weight gain.

Methylation pattern variation between goats and rats during the onset of puberty

Puberty is initiated by increased pulsatile gonadotropin-releasing hormone (GnRH) release from the hypothalamus. Epigenetic repression is thought to play a crucial role in the initiation of puberty, although the existence of analogous changes in methylation patterns across species is unclear. We analysed mRNA expression of DNA methyltransferases (DNMTs) and methyl-binding proteins (MBPs) in goats and rats by quantitative real-time PCR (qRT-PCR). DNA methylation profiles of hypothalamic were determined at the pre-pubertal and pubertal stages by bisulphite sequencing. In this study, expression of DNMTs and MBPs mRNA showed different patterns in goats and rats. Global methylation variation was low in goats and rats, and the profile remained stable during puberty. Gene ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis revealed the involvement of 62 pathways in puberty in goats and rats including reproduction, type I diabetes mellitus and GnRH signalling pathways and found that Edn3, PTPRN2 and GRID1 showed different methylation patterns during puberty in goats and rats and similar variation patterns for Edn3 and PTPRN2 were showed. These indicated that Edn3 and PTPRN2 would play a role in the timing of puberty. This study provides evidence of the epigenetic control of puberty.

MiR-24 alleviates cardiomyocyte apoptosis after myocardial infarction via targeting BIM

OBJECTIVE

Ischemia hypoxia induces cardiomyocyte (CM) apoptosis in the process of acute myocardial infarction (AMI). It was showed that pro-apoptosis factor BIM participates in regulating tumor cell apoptosis under ischemia or hypoxia condition, while its role in CM apoptosis after AMI is still unclear. It was revealed that miR-24 expression was significantly reduced in myocardial tissue after AMI. Bioinformatics analysis exhibits that miR-24 is targeted to the 3'-UTR of BIM. This study aims to investigate the role of miR-24 in mediating BIM expression and CM apoptosis.

PATIENTS AND METHODS

Dual-luciferase assay was used to confirm the targeted regulation between miR-24 and BIM. Cells were cultured under ischemia hypoxia for 12 h after transfection for 48 h. Cell apoptosis was tested by using flow cytometry. The caspase activity was detected by using spectrophotometry. Wistar rats were divided into four groups, including Sham, AMI, AMI + agomir-control, and AMI + agomir-24 groups. Cardiac function was evaluated by using echocardiography. CM apoptosis was determined by using TUNEL. Infarction area was measured by using evans blue staining. MiR-24 targeted suppressed BIM expression.

RESULTS

MiR-24 mimic and/or si-BIM transfection significantly declined the BIM expression, inhibited caspase-9 and caspase-3 activities, and reduced cell apoptosis in H9C2 cells. MiR-24 expression was decreased, while BIM levels were up-regulated in myocardium after AMI. Agomir-24 injection down-regulated the BIM expression in myocardium, reduced CM apoptosis, narrowed infarction area, and improved cardiac function in rats.

CONCLUSIONS

MiR-24 was reduced, whereas BIM was enhanced in the CM after AMI. MiR-24 up-regulation plays a critical role in decreasing BIM expression, reducing CM apoptosis, and improving cardiac function after AMI.

The psychometric properties of the 5-item gratitude questionnaire in Chinese adolescents

WHAT IS KNOWN ON THE SUBJECT?: The GQ-6 is one of the most widely used self-report questionnaires to evaluate the level of gratitude among adults. The GQ-5 appears suitable for adolescents. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: We developed a Chinese version of the GQ-5 and examined evidence for its reliability and validity. Results demonstrated adequate reliability and validity, indicating that it is appropriate for the assessment of gratitude in Chinese adolescents. In addition, Chinese early adolescent females reported higher gratitude than adolescent males. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Screening adolescents who have lower levels of gratitude through the GQ-5 could help identify students who may benefit from empirically validated interventions to promote higher levels of gratitude in an effort to promote positive psychosocial and academic outcomes.

ABSTRACT

Background This study was conducted to evaluate the psychometric properties of the Chinese version of the 5-item Gratitude Questionnaire (GQ-5). Method The sample consisted of 2093 middle school students (46.8% males) in mainland China. Confirmatory factor analysis and multigroup confirmatory factor analysis were performed to examine the factor structure and the measurement equivalence across gender. The convergent validity, Cronbach's α and mean interitem correlations of the GQ-5 were also evaluated. Results The results provided evidence of internal consistency reliability through a Cronbach's α of 0.812 and a mean interitem correlation of 0.463 for the total sample. The results also supported a one-dimensional factor structure. In addition, convergent validity was assessed by statistically significant positive correlations between the GQ-5 and the two subscales of the Children's Hope Scale (CHS) and the Brief Multidimensional Students' Life Satisfaction Scale (BMSLSS) total score. Finally, multigroup confirmatory factor analysis also demonstrated measurement equivalence across gender. Subsequent analyses of latent mean revealed gender differences in early adolescent male and female students. Conclusions The Chinese version of the GQ-5 appears to be a reliable and valid measure of gratitude among Chinese early adolescents. Early adolescent female students reported higher gratitude than early adolescent male students.

Investigation of underlying comorbidities as risk factors for symptomatic human hepatitis E virus infection

BACKGROUND

Symptomatic Hepatitis E virus (HEV) infection occurs in few infected subjects, and the risk factors are not completely known.

AIM

To explore the risk factors for adverse clinical outcomes in acute HEV infections.

METHODS

A large retrospective study was conducted. The baseline characteristics, clinical outcomes, and laboratory data of 512 acute HEV infection cases were analysed using logistic regression models.

RESULTS

All patients exhibited autochthonous sporadic HEV infections, and most were elderly. Their symptoms varied from asymptomatic to severe liver diseases. In all, 215 patients (42.0%) had liver failure and/or decompensation, and 45 (8.2%) patients died within 3 months. Nearly 60% of patients had underlying chronic liver diseases (CLDs), 20% were cirrhotic, and various extrahepatic underlying comorbidities were common. The logistic regression analysis revealed that underlying CLDs, especially cirrhosis, were closely associated with disease severity (OR = 8.78, P < 0.001) but not with mortality in patients with severe liver diseases. In addition to the known factors, including an old age, the male gender and CLDs, we identified pre-existing extrahepatic tumours, diabetes, and chronic respiratory and renal diseases as novel independent predictors for adverse clinical outcomes. Importantly, patients without these four extrahepatic comorbidities showed a much lower mortality rate (4.2%, P < 0.001) than patients with one (18.5%) or more comorbidities (34.5%).

CONCLUSIONS

Previous comorbidities, including tumours, diabetes, and chronic liver, lung and kidney diseases, were independent risk factors for adverse outcomes, especially mortality, in acute HEV infections. This study provides valuable data for improving the prevention and control of HEV infection.

Two-step shoulder delivery method reduces the incidence of shoulder dystocia

OBJECTIVE

io compare two-step method ot shoulder delivery with one-step for the maternal and neonatal outcomes.

MATERIALS AND METHODS

This was a randomized controlled clinical trial. Women scheduled for vaginal delivery without severe complications were enrolled and randomly arranged into two groups. Women in study group were delivered by two-step method for shoulder delivery, that is to wait for at least one contraction after head delivery, and naturally delivery of shoulder. Women in controlled group were delivered by one-step method, that is after the head was delivered, gentle press of head was applied to facility shoulder delivery. Maternal and neonatal outcomes as Apgar score, rate of shoulder dystocia, and postpartum bleeding were recorded. Interval of head to shoulder was timed in second.

RESULTS

The study group had lower rate of shoulder dystocia than that in control group (X²= 4.27,p =0.03), no increasing of asphyxia, and postpartum bleeding. The average interval of head to shoulder in study group was longer than that in control group. There was no difference in interval between shoulder dystocia vs. normal birth group, neither was there a difference in interval between asphyxia babies and normal babies group. By two-step method, the mean value of head to shoulder interval was 59.025 seconds, 95% CI (20.000-150.000 seconds), mean+2xSD = 148.927 seconds. In one-step group, mean was 44.172 seconds, 95% CI= (10.000~105.000 seconds), mean +2xSD = 94.812 seconds.

CONCLUSION

Two-step method of shoulder delivery had a lower rate of shoulder dystocia than one-step method, no increasing of neonatal asphyxia and postpartum bleeding. The longer interval of head to shoulder did not relate to shoulder dystocia and asphyxia. The normal value of head to shoulder interval might be longer than 60 seconds.

Mps1 kinase regulates tumor cell viability via its novel role in mitochondria

Targeting mitotic kinase monopolar spindle 1 (Mps1) for tumor therapy has been investigated for many years. Although it was suggested that Mps1 regulates cell viability through its role in spindle assembly checkpoint (SAC), the underlying mechanism remains less defined. In an endeavor to reveal the role of high levels of mitotic kinase Mps1 in the development of colon cancer, we unexpectedly found the amount of Mps1 required for cell survival far exceeds that of maintaining SAC in aneuploid cell lines. This suggests that other functions of Mps1 besides SAC are also employed to maintain cell viability. Mps1 regulates cell viability independent of its role in cytokinesis as the genetic depletion of Mps1 spanning from metaphase to cytokinesis affects neither cytokinesis nor cell viability. Furthermore, we developed a single-cycle inhibition strategy that allows disruption of Mps1 function only in mitosis. Using this strategy, we found the functions of Mps1 in mitosis are vital for cell viability as short-term treatment of mitotic colon cancer cell lines with Mps1 inhibitors is sufficient to cause cell death. Interestingly, Mps1 inhibitors synergize with microtubule depolymerizing drug in promoting polyploidization but not in tumor cell growth inhibition. Finally, we found that Mps1 can be recruited to mitochondria by binding to voltage-dependent anion channel 1 (VDAC1) via its C-terminal fragment. This interaction is essential for cell viability as Mps1 mutant defective for interaction fails to main cell viability, causing the release of cytochrome c. Meanwhile, deprivation of VDAC1 can make tumor cells refractory to loss of Mps1-induced cell death. Collectively, we conclude that inhibition of the novel mitochondrial function Mps1 is sufficient to kill tumor cells.

Cross-cultural validation of the 20-item Toronto Alexithymia Scale in Chinese adolescents

WHAT IS KNOWN ON THE SUBJECT?: The TAS-20 is the most widely used self-reported questionnaire to assess the level of alexithymia in students and community and clinical samples. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: The TAS-20-C exhibited high levels of reliability and validity, indicating that it is appropriate for the assessment of alexithymia in Chinese adolescents. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Screening adolescents who are at risk of alexithymia through the TAS-20 could help to perform necessary and effective precautions to decrease the adverse effects of alexithymia, such as the risks of developing depressive mood and behavioral problems.

ABSTRACT

Purpose The aim of this study was to examine the psychometric properties of the Chinese version of the 20-item Toronto Alexithymia Scale (TAS-20-C) in a sample of Chinese adolescents. Method Adolescents (n = 1260) recruited from three schools in mainland China completed the TAS-20-C, the somatization subscale of the Symptom Checklist 90 (SCL-90) and Center for Epidemiological Studies Depression Scale (CES-D). Five different factorial models of the TAS-20 were tested using confirmatory factor analysis (CFA). Cronbach's α, mean inter-item correlations and predictive validity were also evaluated. Results Among those five different factorial models, the four-factor structure model was suitable and invariant across gender and age in this sample. The TAS-20-C demonstrated adequate internal reliability. Gender and age accounted for insignificant amounts of variability in total TAS-20-C and factor scores. TAS-20-C total and subscale scores were correlated significantly with SCL-90 somatization subscale and CES-D. Girls scored higher than boys on difficulty identifying feelings (DIF) and pragmatic thinking (PR) subscales. DIF and lack of subjective significance or importance of emotions (IMs) subscale scores were higher among younger than among middle and older adolescents. Implications for Practice Validating the TAS-20 in adolescents is quite important to use it in evaluating adolescents' alexithymia, and screen those at risk of alexithymia.

I148M variant of PNPLA3 increases the susceptibility to non-alcoholic fatty liver disease caused by obesity and metabolic disorders

BACKGROUND

The patatin-like phospholipase 3 (PNPLA3) rs738409 gene polymorphism is an important genetic determinant of non-alcoholic fatty liver disease (NAFLD). However, the associations between liver fat and metabolic traits in rs738409 G allele carriers and the allelic influence on this association have not been fully studied.

AIM

To investigate the influence of the PNPLA3 gene polymorphism on the association of liver fat with serum metabolic factors and carotid atherosclerosis.

METHODS

Liver fat was measured by quantitative ultrasound in 4300 subjects in the Shanghai Changfeng community and analysed for its association with obesity and metabolic factors in individuals with the PNPLA3 CC, CG and GG genotypes.

RESULTS

Non-alcoholic fatty liver disease occurred in 37.9% and 28.8% of the subjects with the GG and CC genotypes respectively (P < 0.001). Liver fat was significantly associated with body mass index, waist circumference, serum triglycerides, high-density lipoprotein cholesterol, fasting blood glucose and insulin in the PNPLA3 rs738409 G allele carriers (P < 0.001). Compared with the CC homozygotes, the GG homozygotes presented higher liver fat and liver fibrosis scores despite their better metabolic status (comparison of regression line slopes, P < 0.05). An increase in liver fat was accompanied by a significant increase in the average and maximum carotid intima-media thickness in subjects with the PNPLA3 CC genotype but not in those with the GG genotype.

CONCLUSIONS

PNPLA3 rs738409 G allele carriers were found to be more susceptible to the metabolic-related hepatic steatosis, and developed NAFLD and liver fibrosis despite presenting relatively better metabolic statuses and lower risks for carotid atherosclerosis.

A common polymorphism rs1800247 in osteocalcin gene was associated with serum osteocalcin levels, bone mineral density, and fracture: the Shanghai Changfeng Study

We evaluated the relationship between a common polymorphism rs1800247 in osteocalcin gene and serum osteocalcin levels, bone mineral density and fracture in Chinese. This was a population-based cross-sectional study. We demonstrated that rs1800247 was associated with bone mineral density and fracture in men and serum osteocalcin levels in women.

INTRODUCTION

This study aimed to evaluate the relationship between a common polymorphism rs1800247 in osteocalcin gene and serum total osteocalcin levels, bone mineral density (BMD) and fracture in Chinese middle-aged and elderly men and women.

METHODS

This was a population-based cross-sectional study included 5561 individuals aged 45 years or older. Information on fractures sustained after age of 45 were collected. BMD at the lumbar spine, femoral neck and total hip were measured using dual-energy X-ray absorptiometry. The genotyping of rs1800247 was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy.

RESULTS

rs1800247 was associated with lumbar spine BMD and femoral neck BMD in the dominant model adjusted for age, body mass index (BMI), serum total osteocalcin in men (both P = 0.04). Besides, rs1800247 was associated with fracture adjusted for age, BMI, serum total osteocalcin and total hip BMD in the additive and dominant models in men (P = 0.04 and 0.01). In the dominant model, the carriers of CC and TC genotypes was associated with a lower odds of fracture compared with the carriers of TT genotype (OR = 0.60, 95%CI 0.40-0.88, P = 0.01). In men, rs1800247 was not associated with serum total osteocalcin levels in additive, dominant or recessive models. However, rs1800247 was associated with serum total osteocalcin levels in all models adjusted for age, BMI, menopausal status and total hip BMD in women (all p < 0.001), with osteocalcin levels decreasing across TT, TC and CC genotypes. rs1800247 was not associated with BMD or fracture in all models in women.

CONCLUSIONS

A common polymorphism rs1800247 in osteocalcin gene may affect the risk of osteoporosis and fracture and serum total osteocalcin levels in Chinese, and there may be gender differences underlying these associations.

Assessment of genetic diversity of bermudagrass germplasm from southwest China and Africa by using AFLP markers

Cynodon dactylon (L.) Pers. var. dactylon (common bermudagrass) is widely distributed geographically between approximately 45°N and 45°S latitude, penetrating to approximately 53°N latitude in Europe. The extensive variation of morphological and adaptive characteristics of the taxon has been substantially documented, but information is lacking on DNA molecular variation in geographically disparate forms. The genetic diversity of 51 wild accessions of bermudagrass from southwest China (Sichuan, Chongqing, Yunnan, Guizhou, and Tibet) and 8 African bermudagrass was analyzed using amplified fragment length polymorphism molecular markers. A total of 670 polymorphic bands were detected with 11 primer combinations, of which 663 (98.74%) bands were found to be polymorphic. The genetic similarity among the accessions ranged from 0.64-0.96 with an average of 0.78. All 59 wild accessions were clustered into 5 eco-geographic groups, and nearly all accessions from the same area were classified into the same group and were found to be associated with their geographical distributions. Therefore, complex geographical and ecological environments are important factors for the genetic structure and geographical distribution of C. dactylon.

A genetic variant in SLC6A20 is associated with Type 2 diabetes in white-European and Chinese populations

AIMS

To investigate whether polymorphisms in SLC6A20 are associated with susceptibility to Type 2 diabetes.

METHODS

In the Rotterdam Study, a prospective, population-based cohort (n = 5974), 22 tagging polymorphisms with minor allele frequencies>0.05 across SLC6A20 were studied. Replication studies were performed in an independent Dutch case-control study (DiaGene-Rotterdam Study 2 n = 3133), and in a Chinese Han case-control population (n = 2279). A meta-analysis of the results was performed.

RESULTS

In the Rotterdam study, the minor alleles of rs13062383, rs10461016 and rs2286489 increased the risk of Type 2 diabetes (hazard ratio 1.37, 95% CI 1.15-1.63, hazard ratio 1.30 95% CI 1.09-1.54 and hazard ratio 1.20, 95% CI 1.07-1.35, respectively). In the DiaGene/Rotterdam Study 2, the A allele of rs13062383 increased the risk of Type 2 diabetes (odds ratio 1.45, 95% CI 1.19-1.76). In the Chinese Han study, the rs13062383 A allele also increased the risk of Type 2 diabetes (odds ratio 1.21, 95% CI 1.03-1.42). Meta-analysis showed a highly significant association of rs13062383 with Type 2 diabetes (odds ratio 1.35, 95% CI 1.21-1.47; P = 3.3 × 10⁻⁸).

CONCLUSIONS

In conclusion, rs13062383 in SLC6A20 increased the susceptibility to Type 2 diabetes in populations with different genetic backgrounds.

Ventilation Distribution Heterogeneity at Rest as a Marker of Exercise Impairment in Mild-to-Advanced COPD

The difference between total lung capacity (TLC) by body plethysmography and alveolar volume (VA) from the single-breath lung diffusing capacity measurement provides an index of ventilation distribution inequalities in COPD. The relevance of these abnormalities to dyspnea and exercise intolerance across the continuum of disease severity remains unknown. Two-hundred and seventy-six COPD patients distributed across GOLD grades 1 to 4 and 67 healthy controls were evaluated. The "poorly communicating fraction" (PCF) of the TLC was estimated as the ratio (%) of TLC to VA. Healthy subjects showed significantly lower PCF values compared to GOLD grades 1 to 4 (10 ± 3% vs. 17 ± 8% vs. 27 ± 10% vs. 37 ± 10% vs. 56 ± 11%, respectively; p < 0.05). Pulmonary gas exchange impairment, mechanical ventilatory constraints and ventilation-corrected dyspnea scores worsened across PCF tertiles (p < 0.05). Of note, GOLD grades 1 and 2 patients with the highest PCF values had pronounced exercise ventilatory inefficiency and dyspnea as a limiting symptom. In fact, dyspnea was a significant contributor to exercise limitation only in those with "moderate" or "extensive" PCF (p < 0.05). A receiver operating characteristics curve analysis revealed that PCF was a better predictor of severely reduced maximal exercise capacity than traditional pulmonary function indexes including FEV1 (area under the curve (95% confidence interval) = 0.85 (0.81-0.89), best cutoff = 33.4%; p < 0.01). In conclusion, PCF is a readily available functional marker of gas exchange and mechanical abnormalities relevant to dyspnea and exercise intolerance across the COPD grades.

Real-time experimental demonstrations of software reconfigurable optical OFDM transceivers utilizing DSP-based digital orthogonal filters for SDN PONs

Real-time optical OFDM (OOFDM) transceivers with on-line software-controllable channel reconfigurability and transmission performance adaptability are experimentally demonstrated, for the first time, utilizing Hilbert-pair-based 32-tap digital orthogonal filters implemented in FPGAs. By making use of an 8-bit DAC/ADC operating at 2GS/s, an oversampling factor of 2 and an EML intensity modulator, the demonstrated RF conversion-free transceiver supports end-to-end real-time simultaneous adaptive transmissions, within a 1GHz signal spectrum region, of a 2.03Gb/s in-phase OOFDM channel and a 1.41Gb/s quadrature-phase OOFDM channel over a 25km SSMF IMDD system. In addition, detailed experimental explorations are also undertaken of key physical mechanisms limiting the maximum achievable transmission performance, impacts of transceiver's channel multiplexing/demultiplexing operations on the system BER performance, and the feasibility of utilizing adaptive modulation to combat impairments associated with low-complexity digital filter designs. Furthermore, experimental results indicate that the transceiver incorporating a fixed digital orthogonal filter DSP architecture can be made transparent to various signal modulation formats up to 64-QAM.