Sildenafil Preserves Diastolic Relaxation After Reduction By L-name And Increases Phosphodiesterase-5 In The Intercalated Discs Of Cardiac Myocytes And Arterioles.

We investigated the influence of sildenafil on cardiac contractility and diastolic relaxation and examined the distribution of phosphodiesterase-5 in the hearts of hypertensive rats that were treated with by NG-nitro-L-arginine methyl ester (L-NAME). Male Wistar rats were treated with L-NAME and/or sildenafil for eight weeks. The Langendorff method was used to examine the effects of sildenafil on cardiac contractility and diastolic relaxation. The presence and location of phosphodiesterase-5 and phosphodiesterase-3 were assessed by immunohistochemistry, and cGMP plasma levels were measured by ELISA. In isolated hearts, sildenafil prevented the reduction of diastolic relaxation (dP/dt) that was induced by L-NAME. In addition, phosphodiesterase-5 immunoreactivity was localized in the intercalated discs between the myocardial cells. The staining intensity was reduced by L-NAME, and sildenafil treatment abolished this reduction. Consistent with these results, the plasma levels of cGMP were decreased in the L-NAME-treated rats but not in rats that were treated with L-NAME + sildenafil. The sildenafil-induced attenuation of the deleterious hemodynamic and cardiac morphological effects of L-NAME in cardiac myocytes is mediated (at least in part) by the inhibition of phosphodiesterase-5.661253-

Sildenafil preserves diastolic relaxation after reduction by L-NAME and increases phosphodiesterase-5 in the intercalated discs of cardiac myocytes and arterioles

OBJECTIVES: We investigated the influence of sildenafil on cardiac contractility and diastolic relaxation and examined the distribution of phosphodiesterase-5 in the hearts of hypertensive rats that were treated with by NG-nitro-L-arginine methyl ester (L-NAME). METHODS: Male Wistar rats were treated with L-NAME and/or sildenafil for eight weeks. The Langendorff method was used to examine the effects of sildenafil on cardiac contractility and diastolic relaxation. The presence and location of phosphodiesterase-5 and phosphodiesterase-3 were assessed by immunohistochemistry, and cGMP plasma levels were measured by ELISA. RESULTS: In isolated hearts, sildenafil prevented the reduction of diastolic relaxation (dP/dt) that was induced by L-NAME. In addition, phosphodiesterase-5 immunoreactivity was localized in the intercalated discs between the myocardial cells. The staining intensity was reduced by L-NAME, and sildenafil treatment abolished this reduction. Consistent with these results, the plasma levels of cGMP were decreased in the L-NAME-treated rats but not in rats that were treated with L-NAME + sildenafil. CONCLUSION: The sildenafil-induced attenuation of the deleterious hemodynamic and cardiac morphological effects of L-NAME in cardiac myocytes is mediated (at least in part) by the inhibition of phosphodiesterase-5

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension

Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Caracterização da ação hipotensora do veneno de Bothrops alternatus em ratos anestesiados

Orientador: Stephen HysloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências MédicasResumo: Venenos de serpentes do gênero Bothrops produzem efeitos locais (dor, edema, inflamação, hemorragia, necrose), e sistêmicos (coagulopatias, hemorragia, hipotensão/choque, insuficiência renal aguda). Neste estudo, avaliamos a ação hipotensora do veneno da B. altematus em ratos anestesiados e investigamos os mediadores envolvidos neste fenômeno. Ratos Wistar machos anestesiadoscom pentobarbital sódico (40 mg/kg, Lp.) foram canulados para medição da pressão arterial (artéria carótida) e administração de veneno e de drogas (veia femora!). A pressão arterial e a freqüência cardíaca foram registradas continuamente durante o experimento. O veneno, suas frações e as drogas foram dissolvidos em salina e administrados in bolus (0,1 ml) após 15 minutos para a estabilização da pressão. Em alguns experimentos o veneno foi dialisado utilizando-se membranas de celulose (limites de filtração de 2 kDa e 12 kDa) antes de ser administrado aos ratos. Para identificar a fração hipotensora, o veneno foi fracionado por gel filtração em resina Superdex 75 e as frações testadas na pressão arterial. O veneno causou hipotensão de ormadose-dependente(1-100j.lg/kg)com quedamáximade 69,8.:!::6,2%na maior dose (média:t desvio padrão, n=5) e com retorno da pressão a 80% dos níveis basais em 30 minoO pré-tratamento de ratos com atropina (antagonista muscarínico; 4 mg/kg, Lv.) ou glibenclamida (antagonista de canais de K+ ATP-dependentes; 50 mg/kg, Lv.) não alterou de forma significativa a hipotensão causada pelo veneno (100 j.lg/kg, Lv.). Por outro lado, o N'úJ-L-nitro-argininameti! éster (L-NAME, 20 mg/kg, Lv.), inibidor da biossíntese de óxido nítrico (NO), reduziu a hipotensão máxima causada pelo veneno (100 j.lg/kg) de 69,8.:!:6,2%para 29,1.:!::16,6%(n=5, p<0,05). Ratos prétratados com captopril (2 mg/kg), um inibidor da enzima conversora da angiotensina e potencializador do efeito da bradicinina, apresentaram acentuação da hipotensão máxima causada pelo veneno (50 j.lg/kg) de 51,2:t5,5% para 80,8:t9,4% (n=5, p<0,05). A indometacina (inibidor da ciclooxigenase, 10 mg/kg, Lv.) causou pequena redução na hipotensão máxima, e potencializou a recuperação da pressão para níveis basais; também aumentou a resistência dos ratos a doses maiores. A pré-incubação do veneno com antiveneno comercial aboliu totalmente a atividade hipotensora enquanto que a administração separada do antiveneno antes ou após o veneno não afetou a hipotensão subseqüente. O veneno dialisado produziu hipotensão de 46,9::t6,8% e 30,3::t5,5% com a dose de 100 ~g/kg após diálise em membranas com limites de filtração de 2 kDa e 12 kDa, respectivamente (p<0,05 comparados à queda de 69,8:!:6,2% com veneno não dialisado). Das frações obtidas por gel filtração do veneno, nenhuma sozinha (100 ~g/kg) reproduziu o efeito observado com o veneno total. Na combinação de frações, apenas as frações 2 e 4 reproduziram o quadro hipotensor do veneno, sendo que a fração 4 potencializou a fração 2. A ação da fração 2 também foi potencializada (p<0,05) pelo captopril enquanto que a fração 4 potencializou (p<0,05) a hipotensão causada pela bradicinina (1 mg/kg, Lv.). Estes resultados mostram que o veneno da B. altematus produziu resposta hipotensora dose-dependente em ratos que foi parcialmente mediada por NO, o qual pode ter sido liberado pela bradicinina proveniente da atividade cininogênica do veneno e presente na fração 2. A ação potencializadora da fração 4 sugere a presença de peptídeos potencializadores da bradicinina no veneno. Metabólitos do ácido araquidônico parecem estar envolvidos mais na manutenção da hipotensão do que na queda inicial. A via muscarínica e os canais de K+ATPdependentes parecem não estar envolvidos na hipotensão induzida pelo venenoAbstract: The venoms of Bothrops snakes produce systemic effects characterized by disseminated bleeding, coagulopathies, shock and acute renal failure. In this study, we investigated the mediators involved in hypotension induced by Bothrops altematus snake venom. Male Wistar rats anesthetized with sodium pentobarbital were cannulated for measurement of blood pressure and heart rate, and for administration of drugs and venom. Venom (1-100 j.!g/kg) produced dosedependent hypotension with no effect on heart rate; a higher dose (200 j.!g/kg)also produced progressive cardiac depression. L-NAME attenuated the venom-induced hypotension whereas captopril potentiated the fali in blood pressure. Indomethacin enhanced the recovery to normal values and prolonged the survival of rats at venom doses up to 200 og/kg, but atropine and glibenclamide had no effect on the hypotensive response. Preincubating venom with commercial antivenom abolished the hypotensive activity. Fractionation of venom by gel filtration chromatography resulted in four peaks, of which only peaks 2 and 4 in combination reproduced the hypotension caused by whole venom. Peak 2 was also potentiated by captopril while peak 4 potentiated the response to bradykinin. These results indicate that the hypotension produced by B. altematus venom is mediated partly by nitric oxide whose formation may be stimulated by bradykinin and potentiated by captopril. Arachidonic acid metabolites may contribute to sustaining the hypotension whereas muscarinic receptors and ATP-dependent K+channels are not involved.MestradoMestre em Farmacologi