299 research outputs found

    Ezrin interacts with the SARS coronavirus spike protein and restrains infection at the entry stage

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    © 2012 Millet et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Entry of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) and its envelope fusion with host cell membrane are controlled by a series of complex molecular mechanisms, largely dependent on the viral envelope glycoprotein Spike (S). There are still many unknowns on the implication of cellular factors that regulate the entry process. Methodology/Principal Findings: We performed a yeast two-hybrid screen using as bait the carboxy-terminal endodomain of S, which faces the cytosol during and after opening of the fusion pore at early stages of the virus life cycle. Here we show that the ezrin membrane-actin linker interacts with S endodomain through the F1 lobe of its FERM domain and that both the eight carboxy-terminal amino-acids and a membrane-proximal cysteine cluster of S endodomain are important for this interaction in vitro. Interestingly, we found that ezrin is present at the site of entry of S-pseudotyped lentiviral particles in Vero E6 cells. Targeting ezrin function by small interfering RNA increased S-mediated entry of pseudotyped particles in epithelial cells. Furthermore, deletion of the eight carboxy-terminal amino acids of S enhanced S-pseudotyped particles infection. Expression of the ezrin dominant negative FERM domain enhanced cell susceptibility to infection by SARS-CoV and S pseudotyped particles and potentiated S-dependent membrane fusion. Conclusions/Significance: Ezrin interacts with SARS-CoV S endodomain and limits virus entry and fusion. Our data present a novel mechanism involving a cellular factor in the regulation of S-dependent early events of infection.This work was supported by the Research Grant Council of Hong Kong (RGC#760208)and the RESPARI project of the International Network of Pasteur Institutes

    Therapeutic aims of drugs offering only progression-free survival are misunderstood by patients, and oncologists may be overly optimistic about likely benefits

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    PURPOSE: The use of novel and often expensive drugs offering limited survival benefit in advanced disease is controversial. Treatment recommendations are influenced by patient characteristics and trial data showing overall response rates (ORR), progression-free survival (PFS) and overall survival (OS). PFS is frequently the primary outcome in licencing studies. PATIENTS AND METHODS: As part of a longitudinal study Assessing the 'VALue' to patients of PROgression Free Survival (AVALPROFS), oncologists completed checklists at baseline following consultations with patients. Questions probed perceived clinical benefits of the drugs to populations in general. Patients completed study-specific interview schedules at baseline, 6 weeks into treatment, and at withdrawal due to toxicity or progression. Patients also completed tumour- and treatment-specific quality of life questionnaires monthly for their time in the study. Only baseline results are reported here. RESULTS: Thirty-two UK oncologists discussed management options with 90 patients with heterogeneous advanced cancers. Oncologists' estimates of medical benefit in general from treatment varied between 10 and 80 %. They expected 46/90 (51 %) of their patients to derive some clinical benefit from the prescribed treatment but were either unsure or expected none for 44/90 (49 %). Predictions of life expectancy were variable but 62 % (56/90) of patients were expected to survive longer with treatment. A majority of patients 51/90 (57 %) had 'no idea' or were 'unclear' what PFS meant and 45/90 (50 %) thought extension of life was the primary therapeutic aim of treatment. CONCLUSION: Discussions between doctors and patients with metastatic disease about future management plans and likely therapeutic gains are challenging. Factors influencing decisions about putative benefits of novel drugs are often applied inconsistently can be overly optimistic and may even contradict published data

    Restoring brain function after stroke - bridging the gap between animals and humans

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    Stroke is the leading cause of complex adult disability in the world. Recovery from stroke is often incomplete, which leaves many people dependent on others for their care. The improvement of long-term outcomes should, therefore, be a clinical and research priority. As a result of advances in our understanding of the biological mechanisms involved in recovery and repair after stroke, therapeutic opportunities to promote recovery through manipulation of poststroke plasticity have never been greater. This work has almost exclusively been carried out in preclinical animal models of stroke with little translation into human studies. The challenge ahead is to develop a mechanistic understanding of recovery from stroke in humans. Advances in neuroimaging techniques now enable us to reconcile behavioural accounts of recovery with molecular and cellular changes. Consequently, clinical trials can be designed in a stratified manner that takes into account when an intervention should be delivered and who is most likely to benefit. This approach is expected to lead to a substantial change in how restorative therapeutic strategies are delivered in patients after stroke

    Long-term prognostic impact of cardiovascular comorbidities in patients with prostate cancer receiving androgen deprivation therapy: A population-based competing risk analysis.

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    Our study investigated how adverse cardiovascular outcomes are impacted by cardiovascular comorbidities in patients with prostate cancer treated by androgen deprivation therapy (ADT). Using prospective, population-based data, all Hong Kong patients with prostate cancer who received ADT during 1 January 1993 to 3 March 2021 were identified and followed up for the endpoint of cardiovascular hospitalization/mortality until 31 September 2021, whichever earlier. Multivariable competing risk regression was used to compare the endpoint's cumulative incidence between different combinations of major cardiovascular comorbidities (heart failure [HF], myocardial infarction [MI], stroke and/or arrhythmia), with noncardiovascular death as competing event. Altogether, 13 537 patients were included (median age 75.9 [interquartile range 70.0-81.5] years old; median follow-up 3.3 [1.5-6.7] years). Compared to those with none of prior HF/MI/stroke/arrhythmia, the incidence of the endpoint was not different in those with only stroke (subhazard ratio [SHR] 1.06 [95% confidence interval (CI): 0.92-1.23], P = .391), but was higher in those with only HF (SHR 1.67 [1.37-2.02], P < .001), arrhythmia (SHR 1.63 [1.35-1.98], P < .001) or MI (SHR 1.43 [1.14-1.79], P = .002). Those with ≥2 of HF/MI/stroke/arrhythmia had the highest incidence of the endpoint (SHR 1.94 [1.62-2.33], P < .001), among whom different major cardiovascular comorbidities had similar prognostic impacts, with the number of comorbidities present being significantly prognostic instead. In conclusion, in patients with prostate cancer receiving ADT, the sole presence of HF, MI or arrhythmia, but not stroke, may be associated with elevated cardiovascular risks. In those with ≥2 of HF/MI/stroke/arrhythmia, the number of major cardiovascular comorbidities may be prognostically more important than the type of comorbidities. [Abstract copyright: © 2023 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Straight impact crater rim segments on Mercury

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    The formation of straight impact crater rims is widely accepted to be influenced by preexisting lithospheric structure. We investigate the distribution and orientations of straight crater rim segments across Mercury. We devise a mapping workflow aimed at minimizing distortions of length and orientation that arise when working on projected image mosaics on a global scale and produce a global map of the rims of 7,145 impact craters with diameters between 20 and 400 km. We extract straight rim segments that maintain consistent orientations for at least 10 km to assess their frequency and orientation. Our dataset shows that 83% of craters have straight rim segments that show strong east–west orientations at the poles and weak north–south or random orientations at lower latitudes. This emphasizes the importance of lithospheric structure for impact cratering on Mercury. Our map dataset provides valuable insights for future investigations into the tectonic evolution of Mercury

    Staging the tumour and staging the host: Pre-treatment combined Neutrophil Lymphocyte Ratio and modified Glasgow Prognostic Score is associated with overall survival in patients with oesophagogastric cancers undergoing treatment with curative intent

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    Background: This study examined whether an innate systemic inflammatory response (SIR) measured by combination neutrophil to lymphocyte ratio (NLR) and modified Glasgow Prognostic Score (mGPS) was associated with overall survival (OS) in patients with esophagogastric cancer (EC) undergoing neoadjuvant chemotherapy (NAC) followed by surgery. Methods: Patients diagnosed with EC, managed with NAC prior to surgery at a regional referral center, between January 2010 and December 2015, were included. The mGPS and NLR were calculated within 12 weeks before NAC. Patients were grouped by combined NLR/mGPS score into three groups of increasing SIR: NLR ≤ 3 (n = 152), NLR &gt; 3 + mGPS = 0 (n = 55), and NLR &gt; 3 + mGPS &gt; 0 (n = 32). Univariable and multivariable Cox regression was used to analyse OS. Results: Overall, 337 NAC patients were included, with 301 (89%) proceeding to surgery and 215 (64%) having R0 resection. There were 203 deaths, with a median follow-up of those alive at censor of 69 months (range 44–114). Higher combined NLR/mGPS score (n = 239) was associated with poorer OS independent of clinical stage and performance status (hazard ratio 1.28, 95% confidence interval 1.02–1.61; p = 0.032), higher rate of progression on NAC (7% vs. 7% vs. 19%; p = 0.003), and lower proportion of eventual resection (80% vs. 84% vs. 53%; p = 0.003). Conclusions: The combined NLR/mGPS score was associated with OS and initial treatment outcomes in patients undergoing NAC prior to surgery for EC, stratifying survival in addition to clinical staging and performance status. The host SIR may be a useful adjunct to multidisciplinary decision making

    MET-PREVENT: metformin to improve physical performance in older people with sarcopenia and physical prefrailty/frailty - protocol for a double-blind, randomised controlled proof-of-concept trial

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    \ua9 Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ. INTRODUCTION: Skeletal muscle dysfunction is central to both sarcopenia and physical frailty, which are associated with a wide range of adverse outcomes including falls and fractures, longer hospital stays, dependency and the need for care. Resistance training may prevent and treat sarcopenia and physical frailty, but not everyone can or wants to exercise. Finding alternatives is critical to alleviate the burden of adverse outcomes associated with sarcopenia and physical frailty. This trial will provide proof-of-concept evidence as to whether metformin can improve physical performance in older people with sarcopenia and physical prefrailty or frailty. METHODS AND ANALYSIS: MET-PREVENT is a parallel group, double-blind, placebo-controlled proof-of-concept trial. Trial participants can participate from their own homes, including completing informed consent and screening assessments. Eligible participants with low grip strength or prolonged sit-to-stand time together with slow walk speed will be randomised to either oral metformin hydrochloride 500 mg tablets or matched placebo, taken three times a day for 4 months. The recruitment target is 80 participants from two secondary care hospitals in Newcastle and Gateshead, UK. Local primary care practices will act as participant identification centres. Randomisation will be performed using a web-based minimisation system with a random element, balancing on sex and baseline walk speed. Participants will be followed up for 4 months post-randomisation, with outcomes collected at baseline and 4 months. The primary outcome measure is the four metre walk speed at the 4-month follow-up visit. ETHICS AND DISSEMINATION: The trial has been approved by the Liverpool NHS Research Ethics Committee (20/NW/0470), the Medicines and Healthcare Regulatory Authority (EudraCT 2020-004023-16) and the UK Health Research Authority (IRAS 275219). Results will be made available to participants, their families, patients with sarcopenia, the public, regional and national clinical teams, and the international scientific community. TRIAL REGISTRATION NUMBER: ISRCTN29932357
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