Risk Stratification for Lung Cancer Patients.

A comprehensive review of relevant clinical literature on evidence-based recommendations and existing prediction models specific to lung cancer surgery was undertaken. Preoperative risk assessment parameters such as pulmonary function tests (PFT), cardiopulmonary exercise testing (CPET), Brunelli models, Thoracoscore and frailty were analyzed for predicting postoperative risk of complications. When assessing fitness for surgery, the primarily used PFT parameters such as predictive postoperative forced expiratory volume in one second (FEV1) and diffusion capacity for carbon monoxide (DLCO ) showed conflicting evidence in determining a positive correlation with postoperative mortality. CPET variables predicted higher complication risk when VO2peak < 10ml/kg/min, AT < 11ml/kg/min and ventilation/carbon dioxide production (VE/VCO2) was in range of 34-40. While a cardiac risk index like the Thoracic Revised Cardiac Risk Index (ThRCRI) predicted major cardiovascular compromise, a thoracic risk index like Thoracoscore proved imprecise. Lastly, frailty is used to risk stratify patients in clinical practice but a recognized validated model specific to thoracic surgery is non-existent. When considering patients for lung cancer surgery, some dilemma exists regarding the accuracy of clinical prediction models and their external validation. There is a pressing need for the development of a consolidated clinically robust risk stratification model to predict complications after thoracic resections.

COVID-19 and congenital heart disease: an insight of pathophysiology and associated risks.

OBJECTIVE: We aimed to examine the literature to determine if both paediatric and adult patients diagnosed with congenital heart disease (CHD) are at a higher risk of poor outcomes if they have the coronavirus disease 2019 (COVID-19), compared to those without CHD. METHODS: A systematic review was executed using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. To identify articles related to COVID-19 and CHD, an extensive literature search was performed on EMBASE, Medline, Scopus, and Global Health databases using keywords and MeSH terms. RESULTS: A total of 12 articles met the inclusion criteria and were included for analysis in this systematic review. Two themes were identified for data extraction: evidence supporting higher risks in CHD patients and evidence against higher risks in CHD patients. After combining the data, there were 99 patients with CHDs out of which 12 required admissions to ICU. CONCLUSION: This systematic review suggests that CHD may increase the risk of poor outcomes for those with COVID-19, but also highlights the necessity for more research with larger sample sizes in order to make a more justified conclusion, as the majority of papers that were analysed were case series and case reports. Future research should aim to quantify the risks if possible whilst accounting for various confounding factors such as age and treatment history.

The regulation and signalling of anti-Müllerian hormone in human granulosa cells: relevance to polycystic ovary syndrome.

STUDY QUESTION: What prevents the fall in anti-Müllerian hormone (AMH) levels in polycystic ovary syndrome (PCOS) and what are the consequences of this for follicle progression in these ovaries? SUMMARY ANSWER: Exposure of granulosa cells (GCs) to high levels of androgens, equivalent to that found in PCOS, prevented the fall in AMH and was associated with dysregulated AMH-SMAD signalling leading to stalled follicle progression in PCOS. WHAT IS KNOWN ALREADY: In normal ovaries, AMH exerts an inhibitory role on antral follicle development and a fall in AMH levels is a prerequisite for ovulation. Levels of AMH are high in PCOS, contributing to the dysregulated follicle growth that is a common cause of anovulatory infertility in these women. STUDY DESIGN, SIZE, DURATION: Human KGN-GC (the cell line that corresponds to immature GC from smaller antral follicles (AF)) were cultured with a range of doses of various androgens to determine the effects on AMH production. KGN-GC were also treated with PHTPP (an oestrogen receptor ß (ERß) antagonist) to examine the relationship between AMH expression and the ratio of ERα:ERß. The differential dose-related effect of AMH on gene expression and SMAD signalling was investigated in human granulosa-luteal cells (hGLC) from women with normal ovaries, with polycystic ovarian morphology (PCOM) and with PCOS. KGN-GC were also cultured for a prolonged period with AMH at different doses to assess the effect on cell proliferation and viability. PARTICIPANTS/MATERIALS, SETTING, METHODS: AMH protein production by cells exposed to androgens was measured by ELISA. The effect of PHTPP on the mRNA expression levels of AMH, ERα and ERß was assessed by real-time quantitative PCR (qPCR). The influence of AMH on the relative mRNA expression levels of aromatase, AMH and its receptor AMHRII, and the FSH and LH receptor (FSHR and LHR) in control, PCOM and PCOS hGLCs was quantified by qPCR. Western blotting was used to assess changes in levels of SMAD proteins (pSMAD-1/5/8; SMAD-4; SMAD-6 and SMAD-7) after exposure of hGLCs from healthy women and women with PCOS to AMH. The ApoTox-Glo Triplex assay was used to evaluate the effect of AMH on cell viability, cytotoxicity and apoptosis. MAIN RESULTS AND THE ROLE OF CHANCE: Testosterone reduced AMH protein secreted from KGN-GC at 10-9-10-7 M (P < 0.05; P < 0.005, multiple uncorrected comparisons Fishers least squares difference), but at equivalent hyperandrogenemic levels no change was seen in AMH levels. 5α-DHT produced a significant dose-related increase in AMH protein secreted into the media (P = 0.022, ANOVA). Increasing the mRNA ratio of ERα:ERß produced a corresponding increase in AMH mRNA expression (P = 0.015, two-way ANOVA). AMH increased mRNA levels of aromatase (P < 0.05, one-way ANOVA) and FSHR (P < 0.0001, one-way ANOVA) in hGLCs from women with PCOM, but not from normal cells or PCOS (normal n = 7, PCOM n = 5, PCOS n = 4). In contrast to hGLCs from ovulatory ovaries, in PCOS AMH reduced protein levels (cell content) of stimulatory pSMAD-1/5/8 and SMAD-4 but increased inhibitory SMAD-6 and -7 (P < 0.05, normal n = 6, PCOS n = 3). AMH at 20 and 50 ng/ml decreased KGN-GC cell proliferation but not viability after 8 days of treatment (P < 0.005, two-way ANOVA). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Luteinised GC from women undergoing IVF have a relatively low expression of AMH/AMHRII but advantageously continue to display responses inherent to the ovarian morphology from which they are collected. To compensate, we also utilised the KGN cell line which has been characterised to be at a developmental stage close to that of immature GC. The lack of flutamide influence on testosterone effects is not in itself sufficient evidence to conclude that the effect on AMH is mediated via conversion to oestrogen, and the effect of aromatase inhibitors or oestrogen-specific inhibitors should be tested. The effect of flutamide was tested on testosterone but not DHT. WIDER IMPLICATIONS OF THE FINDINGS: Normal folliculogenesis and ovulation are dependent on the timely reduction in AMH production from GC at the time of follicle selection. Our findings reveal for the first time that theca-derived androgens may play a role in this model but that this inhibitory action is lost at levels of androgens equivalent to those seen in PCOS. The AMH decline may either be a direct effect of androgens or an indirect one via conversion to oestradiol and acting through the upregulation of ERα, which is known to stimulate the AMH promoter. Interestingly, the ability of GCs to respond to this continually elevated AMH level appears to be reduced in cells from women with PCOS due to an adaptive alteration in the SMAD signalling pathway and lower expression of AMHRII, indicating a form of 'AMH resistance'. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Thomas Addison Scholarship, St Georges Hospital Trust. The authors report no conflict of interest in this work and have nothing to disclose. TRIAL REGISTRATION NUMBER: N/A.

Research experience of resident doctors who attended research methodology courses of the National Postgraduate Medical College of Nigeria.

INTRODUCTION: For over three decades, the National Postgraduate Medical College of Nigeria (NPMCN) has been vested with the responsibility of overseeing postgraduate medical training. The main objective of this study was to assess the residents' perception of research as well as challenges faced in pursing seamless research during their training. MATERIALS AND METHODS: This study was a cross-sectional descriptive survey in 2013. Self-administered questionnaires were distributed to the participants of the annual research methodology workshop in all the 15 faculties of the NPMCN. The questionnaires assessed the residents' previous exposure to research, their publication history and their trainers' input to their own research. Statistical analysis was performed using the Statistical Package for the Social Sciences version 20 software. RESULTS: Four hundred and one resident doctors, out of a total of 415 who attended the course, completed the questionnaires during the study period (96.6% response rate). There were 269 (67.0%) males and 132 (33.0%) females, giving a male-to-female ratio of 2:1. About three-quarters of them admitted that their exposure to research during training was grossly inadequate. Twenty-five percent of them were involved in a previous research before residency training, and a further 70% of respondents were involved in their trainers' research work. Ninety-four percent in our study identified a lack of dedicated time to be spared for research as a major obstacle to research. CONCLUSION: Contribution and exposure to research among postgraduate trainees in Nigeria are low. Lack of dedicated time for research was viewed as the major obstacle to research by most residents.