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Understanding factors associated with post-discharge sleep quality among COVID-19 survivors is important for intervention development.
This study investigated sleep quality and its correlates among COVID-19 patients 6 months after their most recent hospital discharge.
Healthcare providers at hospitals located in five different Chinese cities contacted adult COVID-19 patients discharged between 1 February and 30 March 2020. A total of 199 eligible patients provided verbal informed consent and completed the interview. Using score on the single-item Sleep Quality Scale as the dependent variable, multiple linear regression models were fitted.
Among all participants, 10.1% reported terrible or poor sleep quality, and 26.6% reported fair sleep quality, 26.1% reported worse sleep quality when comparing their current status with the time before COVID-19, and 33.7% were bothered by a sleeping disorder in the past 2 weeks. After adjusting for significant background characteristics, factors associated with sleep quality included witnessing the suffering (adjusted B = −1.15, 95% CI = −1.70, −0.33) or death (adjusted B = −1.55, 95% CI = −2.62, −0.49) of other COVID-19 patients during hospital stay, depressive symptoms (adjusted B = −0.26, 95% CI = −0.31, −0.20), anxiety symptoms (adjusted B = −0.25, 95% CI = −0.33, −0.17), post-traumatic stress disorders (adjusted B = −0.16, 95% CI = −0.22, −0.10) and social support (adjusted B = 0.07, 95% CI = 0.04, 0.10).
COVID-19 survivors reported poor sleep quality. Interventions and support services to improve sleep quality should be provided to COVID-19 survivors during their hospital stay and after hospital discharge.
Eubiosis is the intestinal microbial ecosystem balance between human and microorganisms, whereas a disbalance in this intestinal microbial ecosystem is known as dysbiosis. The relationship between exercise with gut microbiota in humans is poorly studied, although it seems that one of the possible ways to restore eubiosis could be via exercise. This systematic review aimed to examine the scientific literature available on the influence of exercise in the gut microbiota of healthy adults.
A systematic and comprehensive literature search was conducted in PubMed and Web of Science (WOS) from their inception to April 2019. Search terms used were: “Gastrointestinal Microbiome”, “Fecal Microbiota”, “Cecal Microbiota”, “Faecal Microbiota, “Exercises”, “Training” and “Human”.
The initial search retrieved 218 articles and 15 met the inclusion criteria of which 9 were cross-sectional, 3 acute and 3 chronic exercise interventions. Higher levels of physical activity or VO2max were positively associated with alpha-diversity in the 85.7% of the cross-sectional studies (n = 6). We found controversial findings between levels of physical activity or VO2max with Firmicutes, Bacteroidetes and Proteobacteria phylum over cross-sectional studies. However, some studies found that higher levels of physical activity or VO2max were positively related with Verrumicrobia and Actinobacteria, as well as their levels increased after the exercise interventions studies. Furthermore, higher levels of physical activity or VO2max were positively related with short-chain-fatty-acids (SCFAs), as well as their levels increased after a chronic intervention.
The muscle-gut axis is based on the contraction of skeletal muscle during exercise due to the release of myokines. This myokines that seem to play a role in mediating the glucagon-like peptide-1 (GLP-1) secretion in the gut during exercise. GLP-1 is one of the key incretins involved in the whole-body metabolism. On other hand, the gut-muscle axis, relies that the gut microbiota is able to produce SCFAs, which are mediator of mitochondrial energy metabolism in skeletal muscles.
Higher levels of physical activity or VO2max are positively related with higher levels of alpha diversity and some phylum in healthy adults. Moreover, both acute and chronic exercises only influence some phylum. However, the high heterogeneity between studies hampers to draw stronger conclusions. Therefore, further studies are needed to understand the possible mechanism about how exercise could affect healthy human gut microbiota.
Late-life depression has become an important public health problem. Available evidence suggests that late-life depression is associated with all-cause and cardiovascular mortality among older adults living in the community, although the associations have not been comprehensively reviewed and quantified.
To estimate the pooled association of late-life depression with all-cause and cardiovascular mortality among community-dwelling older adults.
We conducted a systematic review and meta-analysis of prospective cohort studies that examine the associations of late-life depression with all-cause and cardiovascular mortality in community settings.
A total of 61 prospective cohort studies from 53 cohorts with 198 589 participants were included in the systematic review and meta-analysis. A total of 49 cohorts reported all-cause mortality and 15 cohorts reported cardiovascular mortality. Late-life depression was associated with increased risk of all-cause (risk ratio 1.34; 95% CI 1.27, 1.42) and cardiovascular mortality (risk ratio 1.31; 95% CI 1.20, 1.43). There was heterogeneity in results across studies and the magnitude of associations differed by age, gender, study location, follow-up duration and methods used to assess depression. The associations existed in different subgroups by age, gender, regions of studies, follow-up periods and assessment methods of late-life depression.
Late-life depression is associated with higher risk of both all-cause and cardiovascular mortality among community-dwelling elderly people. Future studies need to test the effectiveness of preventing depression among older adults as a way of reducing mortality in this population. Optimal treatment of late-life depression and its impact on mortality require further investigation.
We suggest a new method to evaluate stress directionality, the ratio of principal stresses, using nanoindentation by introducing a modified Berkovich indenter that is extended in one direction from the Berkovich indenter. In a nonequibiaxial stress state, the indentation load-depth curves are shifted differently as the extended axis of the indenter is placed in accordance with each principal direction. The indentation load-difference is proportional to each principal stress and the slopes are defined by the normal and parallel conversion factors whose ratio is constant at 0.58. The suggested method was verified by indentation tests using five nonequibiaxial stressed specimens. The evaluated stress directionality results show agreement with the applied reference values within ±20%. Furthermore, we calculated the conversion factor ratios for other modified Berkovich indenters extended to different degrees through finite element analysis and confirmed that the conversion factor ratio was inversely proportional to the extension of the modified Berkovich indenter.
Escherichia coli (E. coli) is the most widely applied model organism in current biological science. As a widespread opportunistic pathogen, E. coli can survive not only by symbiosis with human, but also outside the host as well, which necessitates the evaluation of its response to the space environment. Therefore, to keep humans safe in space, it is necessary to understand how the bacteria respond to this environment. Despite extensive investigations for a few decades, the response of E. coli to the real space environment is still controversial. To better understand the mechanisms how E. coli overcomes harsh environments such as microgravity in space and to investigate whether these factors may induce pathogenic changes in E. coli that are potentially detrimental to astronauts, we conducted detailed genomics, transcriptomic and proteomic studies on E. coli that experienced 17 days of spaceflight. By comparing two flight strains LCT-EC52 and LCT-EC59 to a control strain LCT-EC106 that was cultured under the same temperature conditions on the ground, we identified metabolism changes, polymorphism changes, differentially expressed genes and proteins in the two flight strains. The flight strains differed from the control in the utilization of more than 30 carbon sources. Two single nucleotide polymorphisms (SNPs) and one deletion were identified in the flight strains. The expression level of more than 1000 genes altered in flight strains. Genes involved in chemotaxis, lipid metabolism and cell motility express differently. Moreover, the two flight strains also differed extensively from each other in terms of metabolism, transcriptome and proteome, indicating the impact of space environment on individual cells is heterogeneous and probably genotype-dependent. This study presents the first systematic profile of E. coli genome, transcriptome and proteome after spaceflight, which helps to elucidate the mechanism that controls the adaptation of microbes to the space environment.
A challenge for future deep-ice coring in central Antarctica is to identify an appropriate inert drilling fluid with no undesirable physical or chemical characteristics. The drilling fluids currently in use (kerosene-based fluids with density-increasing additives, ethanol and n-butyl acetate) are not intelligent choices for the future from safety, environmental and some technological standpoints. Recently proposed drilling fluids based upon ESTISOL™ have high viscosity at low temperatures, which severely limits their application in cold environments. This paper presents our research into the application of low-molecular-weight, fatty-acid esters (FAEs), substances commonly used in the fragrance and flavoring industries. According to available data, selected FAEs are not hazardous to human health. Considering density requirements alone, ethyl butyrate and n-propyl propionate best meet our present needs. The viscosities of these two chemicals are also the lowest among studied FAEs, not exceeding 4 mPas at temperatures down to −60°C. Both compounds are highly volatile, and insoluble in water. Such properties are attractive, but the applicability of FAEs to deep, cold, ice drilling can be evaluated only after field-based, practical experiments in test boreholes.
The introduction of low-temperature fluid into boreholes drilled in ice sheets helps to remove drilling cuttings and to prevent borehole closure through visco-plastic deformation. Only special fluids, or mixtures of fluids, can satisfy the very strict criteria for deep drilling in cold ice. The effects of drilling fluid on the natural environment are analyzed from the following points of view: (1) occupational safety and health; (2) ozone depletion and global warming; (3) chemical pollution; and (4) biological pollution. Traditional low-temperature drilling fluids (kerosene-based fluids with density additives, ethanol and n-butyl acetate) cannot be qualified as intelligent choices from the safety, environmental and technological standpoints. This paper introduces a new type of low-temperature drilling fluid composed of synthetic ESTISOLTM esters, which are non-hazardous substances. ESTISOLTM 140 mixtures with ESTISOLTM 165 or ESTISOLTM F2887 have an acceptable density and viscosity at low temperature. To avoid the potential for biological contamination of the subglacial environment, the borehole drilling fluid should be treated carefully on the surface.
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