68 research outputs found

    Association of Aβ with Ceramide-Enriched Astrosomes Mediates Aβ Neurotoxicity

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    Amyloid-β (Aβ) associates with extracellular vesicles termed exosomes. It is not clear whether and how exosomes modulate Aβ neurotoxicity in Alzheimer\u27s disease (AD). We show here that brain tissue and serum from the transgenic mouse model of familial AD (5xFAD) and serum from AD patients contains ceramide-enriched and astrocyte-derived exosomes (termed astrosomes) that are associated with Aβ. In Neuro-2a cells, primary cultured neurons, and human induced pluripotent stem cell-derived neurons, Aβ-associated astrosomes from 5xFAD mice and AD patient serum were specifically transported to mitochondria, induced mitochondrial clustering, and upregulated the fission protein Drp-1 at a concentration corresponding to 5 femtomoles Aβ/L of medium. Aβ-associated astrosomes, but not wild type or control human serum exosomes, mediated binding of Aβ to voltage-dependent anion channel 1 (VDAC1) and subsequently, activated caspases. Aβ-associated astrosomes induced neurite fragmentation and neuronal cell death, suggesting that association with astrosomes substantially enhances Aβ neurotoxicity in AD and may comprise a novel target for therapy

    Улучшение и значительное расширение торговых связей между Йеменом и Египтом

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    This paper explains the volume of trade exchange between the Republic of Yemen and Egypt, as well as its increasing growth, as well as ways to increase and sustain it, due to the two countries' common maritime borders, which have a relationship in this field and communicate the continents in maritime navigation, which Russia and Belarus will benefit from in the import and export of goods between continents.Показаны объем торговых обменов между Республикой Йемен и Египтом, а также их постоянный рост. Описаны способы увеличения и поддержания этого роста благодаря общим морским границам двух стран. Республика Йемен и Египт взаимодействуют в этой сфере, связывая континенты морской навигацией, от которой также могут выиграть Россия и Беларусь при импорте и экспорте товаров

    The Effectiveness of Levosimendan on Veno-Arterial Extracorporeal Membrane Oxygenation Management and Outcome: A Systematic Review and Meta-Analysis

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    Objectives: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides a temporary support system for patients with cardiogenic shock refractory to conventional medical therapies. It has been reported that levosimendan may facilitate VA-ECMO weaning and improve survival. The primary objective of this review was to examine the effect of levosimendan use on VA-ECMO weaning and mortality in critically ill patients on VA-ECMO. Design: MEDLINE, EMBASE, and CENTRAL were searched. A pair of reviewers identified eligible clinical trials. Two reviewers extracted data and independently assessed the risk of bias. A random-effect model was used to combine data. The primary outcome was the success of weaning from VA-ECMO. Measurements and Main Results: Seven studies of observational design, including a total of 630 patients, were selected in the final analysis. The sample size ranged from ten-to-240 patients, with a mean age between 53 and 65 years, and more than half of them underwent cardiac surgeries. The VA-ECMO durations varied between four and 11.6 days. Overall, levosimendan use was significantly associated with successful weaning compared with control (odds ratio [OR] 2.89, 95% CI, 1.53-5.46; poverall effect = 0.001); I2 = 49%). For survival, six studies (n = 617) were included in the meta-analysis involving 326 patients in the levosimendan group and 291 in the comparator group. Pooled results showed a significantly higher survival rate in the levosimendan group (OR 0.46, 95% CI, 0.30-0.71; poverall effect = 0.0004; I2 = 20%). Conclusions: Levosimendan therapy was significantly associated with successful weaning and survival benefit in patients with cardiogenic or postcardiotomy shock needing VA-ECMO support for severe cardiocirculatory compromise. To date, there is limited literature and absence of evidence from randomized trials addressing the use of levosimendan in VA-ECMO weaning. This study may be considered a hypothesis-generating research for randomized controlled trials to confirm its findings

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Droplet Retention on an Incline

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    The present study seeks to understand and predict droplet retention on smooth hydrophobic surfaces. The droplet shape and the advancing and receding contact angles are experimentally measured as a function of droplet size under the action of a gravitational force at different inclination angles. The advancing and receding contact angles are correlated with static contact angle and Bond number. A Volume of Fluid – Continuous Surface Force model with varying contact angles along the triple contact line is developed to predict droplet shape. The model is first verified against a two dimensional analytical solution. It is then used to simulate the shape of a sessile droplet on an incline at various angles of inclination and to deter- mine the critical angle of inclination as a function of droplet size. Good agreement is found between exper- imental measurements and predictions. The contact line profile and contact area are also predicted. The contact area predictions based on a spherical-cap assumption are compared to the numerical predictions and are found to underpredict the droplet contact area
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