Population genetic analyses of SARS-CoV-2 genomes indicated that these viruses evolved into two major types designated L and S , that are well defined by two different SNPs that show nearly complete linkage across the viral strains sequenced to date. Whereas the L type was more prevalent in the early stages of the outbreak in Wuhan, the frequency of the L type decreased after early January Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly. On the other hand, the S type, which is evolutionarily older and less aggressive, might have increased in relative frequency due to relatively weaker selective pressure. These findings strongly support an urgent need for further immediate, comprehensive studies that combine genomic data, epidemiological data, and chart records of the clinical symptoms of patients with coronavirus disease COVID This content is only available as a PDF.
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Abstract Study Objectives Short and long sleep durations are linked to reduced kidney function, but little research has examined how sleep is associated with hydration status. Our aim was to assess the relationship between sleep duration and urinary hydration biomarkers among adults in a cross-cultural context.
Regression results were mixed using Uosm, but in the same direction as Usg. Conclusions Short sleep duration was associated with higher odds of inadequate hydration in US and Chinese adults relative to sleeping 8 hr.
Disrupting the late sleep period may increase risk of dehydration and subsequently lead to acute kidney injury. This study, using cross-sectional data on adults from a US nationally representative survey and a large Chinese cohort, finds that short sleep duration 6 hr , compared with 8 hr of sleep, was associated with higher odds of inadequate hydration using urinary biomarkers.
Longitudinal and experimental research is needed to further examine physiological feedback loops, including the role of vasopressin release during sleep, and recovery processes linking sleep duration and hydration status.
Short sleep was associated with inadequate hydration in a cross-cultural context. Introduction Sleep duration has been associated with myriad health outcomes, including cardiovascular disease, obesity, diabetes, and chronic kidney disease CKD [ 1—5 ]. However, a key aspect of population health, which has received less attention, is how sleep relates to actual hydration status for adults in the general population.
Proper hydration is critical to physiological functioning and health [ 6 , 7 ]. The short-term health consequences of body water deficit, or inadequate hydration, are headaches, fatigue, irritability, dry mouth, visual acuity, and in severe cases, loss of motor function and death [ 8—10 ].
Therefore, identifying biological and behavioral aspects of daily life which are modifiable and related to hydration status may help improve general well-being and reduce risk of chronic conditions associated with dehydration, like urolithiasis kidney stones and urinary tract infections [ 6 ].
Hydration status is part of a tightly linked and regulated hormonal system of renin—angiotensin—aldosterone, which regulates urine concentration and body water conservation [ 6 , 11 ].
Vasopressin is released in response to hydration status, but is also part of a circadian rhythm [ 12 ]. Vasopressin increases in the late sleep period to help avoid dehydration [ 13 , 14 ]. Therefore, missing this sleep period through short sleep may affect vasopressin release and disrupt body water homeostasis [ 14 ].
Long sleep may be associated with worse hydration through changes to vasopressin release as well as higher water losses from respiration and longer periods of water intake restriction [ 13 ]. It is therefore possible that short and long sleep may consequently negatively affect hydration status as well. A significant gap exists in the literature identifying how sleep and hydration status are related. One recent study evaluated the effect of controlled dehydration compared with euhydration on sleep quality and sleep quantity in young, healthy adults [ 17 ].
This study did not find that mild dehydration through body water loss affected either sleep duration or quality. However, this study examined only the direction of mild dehydration effects on sleep and is limited by small sample size. At a population level, it is unclear how sleep may be directly associated with hydration status outside of some common upstream factors, particularly across the lifespan. These factors could serve as confounders to understanding the relationship in any one study site.
Therefore, the objective of this paper is to examine how reported usual night-time sleep duration is associated with urinary measures of hydration status in a nationally representative sample of US adults and a large cohort of Chinese adults. We hypothesize that short and long duration of sleep will be associated with more concentrated urine and higher probability of inadequate hydration across populations.
This survey uses both in-person interviews alongside physical examinations, which take place in Mobile Examination Centers MECs. Data for these analyses come from the —, —, and — cycles. The examination response rate varied between Kailuan study design The Kailuan Study is an ongoing multicenter cohort that includes Chinese adults in Tangshan city, China, which was designed to study risk factors for noncommunicable disease in a Chinese population [ 23 ].
Baseline information e. In , information was collected on sleep habits in 12 adults 10 men and 2 women aged 25—95 years who were evaluated at the Kailuan general hospital, one of the 11 centers, and free of neurodegenerative diseases, as detailed elsewhere [ 2 , 24 , 25 ]. This site was chosen for this analysis because it was the only one where sleep information was collected.
We excluded participants 8. Excluded participants had similar age 55 vs 54 years and body mass index BMI, All participants provided written informed consent. In —, adults provided urine samples in the MEC. These samples were measured for urine specific gravity, or the density of urine relative to water, using a digital hand-held refractometer ATAGO PALS , with automatic temperature compensation. Usg is commonly used for laboratory and field measurements of hydration status and urine concentration [ 26 ].
Usg values vary between 1. The Kailuan Study. A single random midstream morning urine sample was collected from each participant during the interview in Usg was assessed using instrument colorimetric method a reagent strip method, also called the dry chemistry test method [ 28 ] within 2 hr of urine sample collection HMA test strips, Changchun Dirui Medical Technology Co. Changchun, China. All urine samples were measured using a urine analyzer N, Dirui, Changchun, China at the central laboratory of the Kailuan general hospital.
The results of Usg were rounded to 0. Uosm is highly correlated with Usg and is a reliable urinary biomarker of daily hydration status [ 29 ]. Main independent variable: sleep duration National Health and Nutrition Examination Survey Participants were asked about their sleeping habits in their home, using the Computer-Assisted Personal Interviewing CAPI system, as part of the survey participant household interview. The Kailuan Study Participants were asked to report usual total hours of actual sleep during the night to the half hour and also did not take into account daytime naps.
Based on previous research that has indicated a U-shaped pattern between hours of sleep and health outcomes where both short sleep and long sleep were seen as potential risk factors [ 1 ], we categorized sleep based on the latest recommendations at less than 6 hr of sleep, 6, 7, 8, and 9 hr or more hours of sleep [ 30 ].
We treated 8 hr of sleep as the reference category since this is often viewed as an ideal sleep duration by sleep experts [ 31 ]. Covariates We adjusted for several known confounders in this analysis depending on data availability by site. The AMPM recall method minimizes bias by improving respondent recall of foods and beverages consumed in the previous 24 hr period from midnight to midnight through standardized probes [ 38 ].
The Global Physical Activity Questionnaire was used to construct the physical activity variable [ 39 ]. During the home interview, participants were asked, using the CAPI system, to list the total time they spent in the previous week in moderate and vigorous activities from biking or walking, work, and leisure activities. Physical activity was dichotomized based on whether the individual met national guidelines of min or more per week of moderate or vigorous physical activity [ 40 ].
Adults with HbA1C values of 6. Medication information if they had taken prescription medications in the last 30 days was obtained through self-report by showing the container to the interviewer. The prescriptions were coded by NCHS. The codes for any diuretic medication e. In the Kailuan Study, information on potential confounders was collected via questionnaire i. Medication use data were collected on participants and all diuretic drugs were coded to exclude participants based on participant self-report.
Analyses were conducted in Stata Because we controlled for dietary intake variables, we used day one dietary sample weights to adjust for over-sampling, nonresponse, noncoverage, and day of the week. Descriptive statistics characterizing the NHANES samples were estimated with and without exclusions for adults with diabetes and those who reported taking a diuretic prescription medication in the past 30 days to estimate the relationship between sleep and hydration status for the full samples and a healthier subset Table 1.
Auslandsstudium in China – Was man für ein Studium in China wissen muss
Inhalt[ Bearbeiten Quelltext bearbeiten ] T. Campbell , Seite Beim Menschen wurden estrogene Effekte oder nachteilige Wirkungen auf die Entwicklung der Geschlechtsorgane und die Fruchtbarkeit jedoch bisher nicht nachgewiesen. Diese Kritik sollte ernst genommen werden, denn dadurch relativierten sich einige der Schlussfolgerungen der Buchautoren. Dieser Umstand mindere aber kaum die Aussagekraft des Buches. Leitzmann verweist darauf, dass von den 18 Kapiteln auf Seiten lediglich ein Unterkapitel mit 43 Seiten die Ergebnisse der China Study beschreibt. Campbell analysiere zudem zahlreiche wissenschaftliche Ergebnisse, die von diversen Forschergruppen im Laufe der Jahre publiziert wurden.
Freie Universität Berlin
I totally loved this book as of page or so! The cancer also barely grew at all in rats that were fed low to medium to high amounts of PLANT protein wheat protein and soy protein were tested. I thought they were going to do a lot more tests to find out the effects of OTHER animal proteins besides casein what about whey protein, fish protein, beef protein, chicken protein, etc , and I thought they would do tests with other carcinogens besides aflatoxin. I am perplexed by this. Also, it makes no sense because there are plenty of organizations like Physicians Committee for Responsible Medicine and PETA that would have the money to sponsor the research.
Dies ist jedoch in der Regel die angenehmste Variante. Dann kommt es weiterhin auch auf das eigene Studienfach an. Und Auf was muss ich bei der Bewerbung achten? Das kann ein erster Schritt sein, um die Auswahl einzugrenzen. Auch hier werden jedoch oft Motivationsschreiben oder Sprachnachweise verlangt.