640 research outputs found
Cardiovascular Response to High Altitude Hypoxia
Normal and abnormal cardiovascular response to high altitude (HA) hypoxia were studied in 98 healthy subjects and in 15 patients with HA pulmonary oedema (HAPO) and acute mountain sickness (AMS) at an altitudeof 3,658 m. The healthy sea level (SL) residents showed marked blood volume changes during the first week with pulmonary hypotension and depression of left ventricular (LV) performance and physical work capacity (PWC). The HA natives, however, had better LV performance and PWC indicating a better adaptation to HA hypoxia. HAPO subjects showed evidence of severe pulmonary hypertension with normal left atrial pressures but the exact mechanism of this condition is still not clear. AMS subjects showed no circulatory abnormalities 'but had relative hypercapnia and severe hypoxemia suggesting that AMS may be causcd by relative hyposensitiveness of the respiratory centre to hypoxia or hypercapnia
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Risk threshold for surgical prevention of ovarian cancer
BACKGROUND: Risk-reducing salpingo-oophorectomy (RRSO) is the most effective intervention to prevent ovarian cancer (OC). It is only available to high-risk women with >10% lifetime OC risk. This threshold has not been formally tested for cost-effectiveness. OBJECTIVE: To specify the OC risk thresholds for RRSO being cost-effective for preventing OC in premenopausal women. METHODS: The costs as well as effects of surgical prevention ('RRSO') were compared over a lifetime with 'no RRSO' using a decision analysis model. RRSO was undertaken in premenopausal women >40 years. The model was evaluated at lifetime OC risk levels: 2%, 4%, 5%, 6%, 8% and 10%. Costs and outcomes are discounted at 3.5%. Uncertainty in the model was assessed using both deterministic sensitivity analysis and probabilistic sensitivity analysis (PSA). Outcomes included in the analyses were OC, breast cancer (BC) and additional deaths from coronary heart disease. Total costs and effects were estimated in terms of quality-adjusted life-years (QALYs); incidence of OC and BC; as well as incremental cost-effectiveness ratio (ICER). DATA SOURCES: Published literature, Nurses Health Study, British National Formulary, Cancer Research UK, National Institute for Health and Care Excellence guidelines and National Health Service reference costs. The time horizon is lifetime and perspective: payer. RESULTS: Premenopausal RRSO is cost-effective at 4% OC risk (life expectancy gained=42.7 days, ICER=£19 536/QALY) with benefits largely driven by reduction in BC risk. RRSO remains cost-effective at >8.2% OC risk without hormone replacement therapy (ICER=£29 071/QALY, life expectancy gained=21.8 days) or 6%if BC risk reduction=0 (ICER=£27 212/QALY, life expectancy gained=35.3 days). Sensitivity analysis indicated results are not impacted much by costs of surgical prevention or treatment of OC/ BC or cardiovascular disease. However, results were sensitive to RRSO utility scores. Additionally, 37%, 61%, 74%, 84%, 96% and 99.5% simulations on PSA are cost-effective for RRSO at the 2%, 4%, 5%, 6%, 8% and 10% levels of OC risk, respectively. CONCLUSIONS: Premenopausal RRSO appears to be extremely cost-effective at ≥4% lifetime OC risk, with ≥42.7 days gain in life expectancy if compliance with hormone replacement therapy is high. Current guidelines should be re-evaluated to reduce the RRSO OC risk threshold to benefit a number of at-risk women who presently cannot access risk-reducing surgery.The study is supported by researchers at the National Institute for Health Research University College London Hospitals Biomedical Research CentreThis is the author accepted manuscript. It is currently under an indefinite embargo pending publication by BMJ Group
Variation in Outcome Reporting in Studies of Fertility-Sparing Surgery for Cervical Cancer: a Systematic Review.
BACKGROUND: Cervical cancer affects 3,197 women in the UK, and 604000 women worldwide annually, with peak incidence seen between 30-34 years of age. For many, fertility-sparing surgery is an appealing option where possible. However, absence of large-scale data, along with a notable variation in reported outcomes in relevant studies may undermine future efforts for consistent evidence synthesis. OBJECTIVES: To systematically review the reported outcomes measured in studies that include women who underwent fertility-sparing surgery for cervical cancer and identify whether variation exists. SEARCH STRATEGY: We searched MEDLINE, EMBASE, and CENTRAL from inception to February 2019. SELECTION CRITERIA: Randomised controlled trials, cohort and observational studies, and case studies of more than 10 participants from January 1990 to date. DATA COLLECTION AND ANALYSIS: Study characteristics and all reported treatment outcomes. MAIN RESULTS: 104 studies with a sum of 9535 participants were identified. Most studies reported on oncological outcomes (97/104), followed by fertility and pregnancy (86/104), post-operative complications (74/104), intra-operative complications (72/104), and quality of life (5). There were huge variation and heterogeneity in reported outcomes, with only 12% being good quality and 87% being of poor quality. CONCLUSIONS: There is significant heterogeneity in the reported outcomes. An agreed Core Outcome Set (COS) is necessary for future studies to effectively harmonise reported outcomes that are measurable and relevant to patients, clinicians, and researchers. This systematic review sets the groundwork for the development of a COS for fertility-sparing surgery in cervical cancer
Bioactivity and In Silico Studies of Isoquinoline and Related Alkaloids as Promising Antiviral Agents: An Insight
Viruses are widely recognized as the primary cause of infectious diseases around the world. The ongoing global pandemic due to the emergence of SARS-CoV-2 further added fuel to the fire. The development of therapeutics becomes very difficult as viruses can mutate their genome to become more complex and resistant. Medicinal plants and phytocompounds could be alternative options. Isoquinoline and their related alkaloids are naturally occurring compounds that interfere with multiple pathways including nuclear factor-κB, mitogen-activated protein kinase/extracellular-signal-regulated kinase, and inhibition of Ca²⁺-mediated fusion. These pathways play a crucial role in viral replication. Thus, the major goal of this study is to comprehend the function of various isoquinoline and related alkaloids in viral infections by examining their potential mechanisms of action, structure-activity relationships (SAR), in silico (particularly for SARS-CoV-2), in vitro and in vivo studies. The current advancements in isoquinoline and related alkaloids as discussed in the present review could facilitate an in-depth understanding of their role in the drug discovery process
Investigating the Impact of Ultra-Radical Surgery on Survival in Advanced Ovarian Cancer Using Population-Based Data in a Multicentre UK Study
We investigated URS and impact on survival in whole patient cohorts with AOC treated within gynaecological cancer centres that participated in the previously presented SOCQER 2 study. National cancer registry datasets were used to identify FIGO Stage 3,4 and unknown stage patients from 11 cancer centres that had previously participated in the SOCQER2 study. Patient outcomes’ association with surgical ethos were evaluated using logistic regression and Cox proportional hazards. Centres were classified into three groups based on their surgical complexity scores (SCS); those practicing mainly low complexity, (5/11 centres with >70% low SCS procedures, 759 patients), mainly intermediate (3/11, 35–50% low SCS, 356 patients), or mainly high complexity surgery (3/11, >35% high SCS, 356 patients). Surgery rates were 43.2% vs. 58.4% vs. 60.9%. across mainly low, intermediate and high SCS centres, respectively, p < 0.001. Combined surgery and chemotherapy rates were 39.2% vs. 51.8% vs. 38.3% p < 0.000 across mainly low, intermediate and high complexity groups, respectively. Median survival was 23.1 (95% CI 19.0 to 27.2) vs. 22.0 (95% CI 17.6 to 26.3) vs. 17.9 months (95% CI 15.7 to 20.1), p = 0.043 in mainly high SCS, intermediate, and low SCS centres, respectively. In an age and deprivation adjusted model, compared to patients in the high SCS centres, patients in the low SCS group had an HR of 1.21 (95% CI 1.03 to 1.40) for death. Mainly high/intermediate SCS centres have significantly higher surgery rates and better survival at a population level. Centres that practice mainly low complexity surgery should change practice. This study provides support for the utilization of URS for patients with advanced OC
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