Does dexmedetomidine reduce the risk of acute kidney injury after cardiac surgery? A meta-analysis of randomized controlled trials

Abstract Background: Acute Kidney Injury (AKI) is a common complication after cardiac surgery and has been associated with poor outcomes. Dexmedetomidine (DEX) has been shown to confer direct renoprotection based on some animal and clinical studies, but data from other trials came to the opposite conclusion following cardiac surgery. This meta-analysis was conducted to evaluate the effects of perioperative DEX administration on the occurrence of AKI and the outcomes after cardiac surgery. Methods: We searched databases including EMBASE, PubMed, and Cochrane CENTRAL for Randomized Controlled Trials (RCTs) focused on DEX for AKI in adult patients after cardiac surgery. The primary outcome was incidence of AKI. Secondary outcomes were Mechanical Ventilation (MV) duration, Intensive Care Unit (ICU) Length Of Stay (LOS), hospital LOS and mortality. Results: Fifteen trials enrolling 2907 study patients were collected in the meta-analyses. Compared with controls, DEX reduced the incidence of postoperative AKI (Odds Ratio [OR = 0.66]; 95% Confidence Interval [95% CI 0.48-0.91]; p = 0.01), and there was no significant difference between groups in postoperative mortality (OR = 0.63; 95% CI 0.32-1.26; p = 0.19), MV duration (Weighted Mean Difference [WMD = -0.44]; 95% CI -1.50-0.63; p = 0.42), ICU LOS (WMD = -1.19; 95% CI -2.89-0.51; p = 0.17), and hospital LOS (WMD = -0.31; 95% CI -0.76-0.15; p = 0.19). Conclusions: Perioperative DEX reduced the incidence of postoperative AKI in adult patients undergoing cardiac surgery. No significant decrease existed in mortality, MV duration, ICU LOS and hospital LOS owing to DEX administration.

Strength training methods for skiers / Métodos de treinamento de força para esquiadores / Métodos de entrenamiento de fuerza para esquiadores

ABSTRACT Introduction: The ski jumping sequence can be divided into four steps: support, take-off, flight, and landing. Each stage has specific tasks and functions and is closely related, with the completion of each stage depending on the previous one. Objective: Explore the effectiveness of special strength training methods for ski sportsmen. Methods: Using the method of scientific literature review, expert interview, experience, and mathematical statistics to perform the special strength training for Chinese ski athletes, comparing the changes in the jump speed and take-off of the big jumps before and after 16 weeks of strength training with a specially developed protocol. Results: There were significant differences in take-off speed and air height before and after the experiment (P<0.05). The athletes in the experimental group significantly differed in takeoff speed before and after participation in the experiment (P=0.01). Conclusion: The experimental results fully evidence that by improving the rapid contraction strength of flexor and extensor muscles of the trunk and hip joints, modern abdominal center strength training methods are more effective than traditional methods. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: A sequência de saltos de esqui pode ser dividida em quatro etapas: apoio, decolagem, voo e pouso. Cada etapa tem tarefas e funções específicas e está intimamente relacionada, sendo a conclusão de cada etapa dependente da etapa anterior. Objetivo: Explorar a eficácia dos métodos especiais de treinamento de força para esportistas em esqui. Métodos: Usando o método de análise científica literária, entrevista com especialistas, experiência e estatísticas matemáticas para realizar o treinamento de força especial para atletas chineses de esqui, comparando as mudanças na velocidade de salto e decolagem dos grandes saltos antes e depois de 16 semanas de treinamento de força com um protocolo especialmente desenvolvido. Resultados: Houve diferenças significativas na velocidade de decolagem e na altura aérea antes e depois do experimento (P<0,05). Os atletas do grupo experimental tiveram uma diferença muito significativa na velocidade de decolagem antes e depois da participação no experimento (P=0,01). Conclusão: Os resultados experimentais evidenciaram plenamente que ao melhorar a força de contração rápida dos músculos flexores e extensores das articulações do tronco e quadril, os métodos modernos de treinamento de força do centro abdominal são mais eficazes do que os métodos tradicionais de treinamento. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: La secuencia de salto de esquí puede dividirse en cuatro pasos: apoyo, despegue, vuelo y aterrizaje. Cada paso tiene tareas y funciones específicas y está estrechamente relacionado, siendo la conclusión de cada paso dependiente del anterior. Objetivo: Explorar la eficacia de los métodos especiales de entrenamiento de la fuerza para los deportistas de esquí. Métodos: Utilizando el método de revisión de la literatura científica, la entrevista a expertos, la experiencia y la estadística matemática para realizar el entrenamiento de fuerza especial para los atletas de esquí chinos, comparando los cambios en la velocidad de salto y el despegue de los grandes saltos antes y después de 16 semanas de entrenamiento de fuerza con un protocolo especialmente desarrollado. Resultados: Hubo diferencias significativas en la velocidad de despegue y la altura del aire antes y después del experimento (P<0,05). Los atletas del grupo experimental tuvieron una diferencia muy significativa en la velocidad de despegue antes y después de la participación en el experimento (P=0,01). Conclusión: Los resultados experimentales evidencian plenamente que, al mejorar la fuerza de contracción rápida de los músculos flexores y extensores de las articulaciones del tronco y la cadera, los métodos modernos de entrenamiento de la fuerza del núcleo abdominal son más eficaces que los métodos de entrenamiento tradicionales. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Short-term exposure to ambient ozone associated with cardiac arrhythmias in healthy adults / 《全球健康杂志（英文）》

Objective:The exact biological mechanism whereby exposure to ambient ozone(O3)may contribute to clinical onset of cardiovascular events remains unclear.In this study,we aim to examine the impacts of O3 exposure on cardiac arrhythmias and potential pathways involved through autonomic dysfunction and myocardial injury.Methods:Seventy-three non-smoking healthy adults were followed with 4 repeated measurements of 24-hour ambulatory arrhythmias,heart rate variability,ST-segment deviation,and blood pressure(BP)in Beijing,China,2014-2016.Generalized additive mixed models coupled with distributed lag nonlinear models were constructed to evaluate the associations and potential interlinks between O3 exposure and outcome measurements.Results:During the study period,24-hour average concentrations of ambient O3 were 47.4 μg/m3(ranging from 1.0 to 165.9 μg/m3).Increased risks of premature ventricular contraction and ventricular tachycardia were associated with interquartile range increases in O3 exposure during the last 5 days before each participant's clinic visit,with relative risks of 2.14(95％confidence interval[CI]:1.95 to 2.32)and 5.47(95％CI:3.51 to 7.43),respectively.Mediation analyses further showed that sympathetic activation,parasympathetic inhibition,and elevated BP levels,as well as heightened risks of ST-segment depression could mediate up to 47.74％of the risks of arrhythmias attributable to O3 exposure.Conclusion:Our results suggest that short-term exposure to ambient O3 could prompt the genesis of arrhythmias partially through worsening autonomic function and myocardial burden.

An extended analysis of cardiovascular benefits of indoor air filtration intervention among elderly:a randomized crossover trial(Beijing indoor air purifier study,BIAPSY) / 《全球健康杂志（英文）》

Objective:Evidence on potential cardiovascular benefits of personal-level intervention among the elderly exposed to high levels of particulate matter(PM)remains limited.We aimed to assess improvements in surrogate markers of cardiovascular injury in vulnerable populations at risks by using indoor air filtration units.Methods:We conducted a randomized crossover trial for 2 separate 2-week air filtration interventions in 20 households of patients with stable chronic obstructive pulmonary disease and their partners in the winter of 2013,with concurrent measurements of indoor PM.The changes in biomarkers indicative of cardiac injury,atherosclerosis progression and systemic inflammation following intervention were evaluated using linear mixed-effect models.Results:In the analysis,average levels of indoor PM with aerodynamic diameters＜2.5 μm(PM2.5)decreased significantly by 59.2％(from 59.6 to 24.3 μg/m3,P＜0.001)during the active air filtration.The reduction was accompanied by improvements in levels of high-sensitivity cardiac troponin I by-84.6％(95％confidence interval[CI]:-90.7 to-78.6),growth differentiation factor-15 by-48.1％(95％CI:-31.2 to-25.6),osteoprotegerin by-65.4％(95％CI:-56.5 to-18.7),interleukin-4 by-46.6％(95％CI:-62.3 to-31.0)and myeloperoxidase by-60.3％(95％CI:-83.7 to-3.0),respectively.Conclusion:Indoor air filtration intervention may provide potential cardiovascular benefits in vulnerable popu-lations at risks.

Age at menarche and associated factors of female junior middle school students in Tianjin area / 中国学校卫生

Objective@#This study aims to investigate the menarcheal age of female junior middle school students in Tianjin and associated factors, providing suggestions for further development of adolescence education on physiological and mental health.@*Methods@#A total of 4 127 junior middle school girls in Tianjin area were selected by stratified random sampling method, and investigated by the method of physical examination and questionnaire survey, results were analyzed.@*Results@#There were 1 383 girls reported menarche. Mean age at menarche was(12.68±1.19) years old; One-way ANOVA showed that girls with higher family income, higher parental education had earlier menarcheal age(F=4.97, 9.52, 10.64, P<0.05). It showed that the tendency that obesity group and over-weight group was higher in the rate of menarche than that of normal group and marasmus group(F=4.20, P<0.05). However, different time on watching TV, computer or celephone and sleeping was found to be unrelated with age at menarche(P>0.05). Kruskal Wallis H test showed that girls whose mothers’ AAM was earlier had earlier menarcheal age(H=82.94, P<0.05). According to age, girls were divided into groups of 10-11, 11-12, 12-13 and 13-14 years old. Girls in each age group were divided into the menstruation menarche group and the non-menstruation menarche group. The results showed that the levels of height, weight, BMI, waist circumference, hip circumference, and the skin fold thickness in menstruation group were higher than those in non-menstruation group(t=2.18-10.93, P<0.05). After that, girls of each group were divided into four group：marasmus group, the normal group, the over-weight group and the obesity group according to BMI(χ2=34.66，13.37，11.09，12.60,P<0.05).@*Conclusion@#Female junior middle school students’ menarcheal age in Tianjin is related to family income, parents’education, mother’s age at menarche, obesity and physical exercise frequency.