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Backgrounds Night-shift workers are exposed to nocturnal light and are more prone to circadian rhythm disorders. Although night-shift work is thought to be associated with the decrease in melatonin secretion, studies have shown inconsistent results. Methods This systematic review and meta-analysis studied the association between night-shift work and melatonin levels. Pubmed and Embase databases were used for literature searching. The pooled standardized mean differences (SMDs) and 95% confidence intervals (CIs) were used to compare the differences between night-shift workers and the controls. Results Thirty-three studies reported in 25 articles (1845 night-shift workers and 3414 controls, mean age 45.12 years) were included after a systematic literature review. Data of circulating melatonin levels and its metabolites, 6-sulfatoxymelatonin (aMT6s) in urine were collected for meta-analysis. The results showed that the first morning-void aMT6s level in night-shift workers was significantly lower than in day workers (SMD = −0.101, 95% CI = −0.179 to −0.022, P = 0.012). The level of mean 24-h urinary aMT6s was lower in night-shift workers than day workers (SMD: −0.264, 95% CI: −0.473 to −0.056, P = 0.013). Among fixed night-shift workers, the level of circulating melatonin, as well as first morning-void aMT6s was lower than that of day workers. Conclusion Our findings indicate that experience of night-shift work is associated with suppression of melatonin production, especially among fixed night-shift workers.

[11C]-S-methyl-16-thiopalmitic acid (a) was developed with excellent heart-to-background uptake ratios and higher retention in heart. Myocardial uptake and metabolism of the tracer is markedly higher CPT I dependent. When compared to [11C]-S-methyl-14-thiomyristic acid (b), [11C]-S-methyl-12-thiododecanoic acid (c) and [11C]-palmitate, a showed an early high uptake and a significantly slower late clearance in heart and a prolonged myocardial elimination half-life (30 min). Analysis of heart tissue and urine samples showed that a was metabolized via beta-oxidation in myocardium. Small animal PET images of the accumulation of a in the rat myocardium were clearly superior to [11C]-palmitate. These initial studies suggest that a could be a potentially useful clinical PET tracer to assess myocardial fatty acid metabolism.

Background: Night-shift workers are exposed to nocturnal light and are more prone to develop circadian rhythm disorders. Although night-shift work is thought to be associated with decreasing levels of melatonin, studies have showed inconsistent results. Methods: This systematic review and meta-analysis studied the association between night-shift work and levels of melatonin and its metabolite, 6-sulfatoxymelatonin (aMT6s). PubMed and EMBASE databases were searched up to August 30, 2019. The difference in melatonin levels between night-shift workers and day workers was statistically quantified by standardized mean difference (SMD) and 95% confidence interval (CI). Findings: Thirty-three studies reported in 25 articles (1,845 night-shift workers and 3,414 controls, mean age 45.12 years) were included after systematic literature review. Pooled results showed that first morning-void aMT6s level in night-shift workers was significantly lower than in day workers (SMD = -0.101, 95% CI= -0.179 to -0.022, P =0.012). The level of mean 24-hour urinary aMT6s was lower in night-shift workers than day workers (SMD: -0.264, 95% CI: -0.473 to -0.056, P = 0.013). Among fixed night-shift workers, the level of circulating melatonin, as well as first morning-void aMT6s was lower than that of day workers. Interpretation: The exposure of night-shift work is inversely associated with the levels of urinary aMT6s and blood melatonin. Night-shift workers experience to chronic reduction in melatonin which might introduce a high risk of carcinoma. Public health and medical services are needed to relieve the harm of night-shift work. Funding Statement: This work was supported by Natural Science Foundation of Shandong Province, China (No. ZR2017MH100). Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: The study protocol was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and was registered in the PROSPERO database.

Background Flood-related damage can be very severe and include health effects. Among those health impacts, infectious diseases still represent a significant public health problem in China. However, there have been few studies on the identification of the spectrum of infectious diseases associated with floods in one area. This study aimed to quantitatively identify sensitive infectious diseases associated with floods in Guangxi, China. Methods A time-trend ecological design was conducted. A descriptive analysis was first performed to exclude infectious diseases with low incidence from 2005 to 2012 in ten study sites of Guangxi. The Wilcoxon rank-sum test was applied to examine the difference in the ten-day attack rate of infectious diseases between the exposure and control periods with different lagged effects. Negative binomial, zero-inflated Poisson and zero-inflated negative binomial models were used to examine the relationship and odd ratios (ORs) of the risk of floods on infectious diseases of preliminary screening. Results A total of 417,271 infectious diseases were notified. There were 11 infectious diseases associated with floods in the preliminary screening process for flood-sensitive infectious diseases. The strongest effect was shown with a 0–9 ten-day lag in different infectious diseases. Multivariate analysis showed that floods were significantly associated with an increased the risk of bacillary dysentery (odds ratio (OR) = 1.268, 95% confidence interval (CI): 1.072–1.500), acute haemorrhagic conjunctivitis (AHC, OR = 3.230, 95% CI: 1.976–5.280), influenza A (H1N1) (OR = 1.808, 95% CI: 1.721–1.901), tuberculosis (OR = 1.200, 95% CI: 1.036–1.391), influenza (OR = 2.614, 95% CI: 1.476–4.629), Japanese encephalitis (OR = 2.334, 95% CI: 1.119–4.865), and leptospirosis (OR = 1.138, 95% CI: 1.075–1.205), respectively. Conclusion The spectrum of infectious diseases which are associated with floods are bacillary dysentery, AHC, influenza A (H1N1), tuberculosis, influenza, Japanese encephalitis and leptospirosis in Guangxi. Floods can result in differently increased risk of these diseases, and public health action should be taken to control a potential risk of these diseases after floods., Highlights • The health effects of floods on infectious diseases are complex and far-reaching. • First time to quantitatively identify sensitive infectious diseases associated with floods. • Floods have different impacts on sensitive infectious diseases and bring more risk of AHC and influenza.

Posttranslational modifications of histone tails are crucial epigenetic marks that regulate diverse cellular processes. Histone lysine methylation activates or represses transcription, depending on the site and degree of these modifications. Two classes of histone lysine demethylases remove histone methylation. Lysine demethylase 1 (KDM1, also known as LSD1) is a flavin adenine dinucleotide (FAD)-containing enzyme that removes mono-/di-methylation. The Jumonji C-terminal domain (JmjC) family of histone demethylases uses Fe(2+) and α-ketoglutarate as cofactors to remove all methylation states. Structural studies have provided insights into the overall architecture, the catalytic mechanism, and the substrate specificity of histone demethylases. Here, we review these exciting advances in the structure biology of histone demethylases and discuss the general principles applicable to other histone-modifying enzymes.

The thermodynamic properties of 75 polyfluorinated dibenzo-p-dioxins (PFDDs) in the ideal gas state at 298.15K and 1.013x10(5) Pa have been calculated at the B3LYP/6-311G* level using Gaussian 03 program. The isodesmic reactions were designed to calculate standard enthalpy of formation (DeltaH(f)(degrees)) and standard free energy of formation (DeltaG(f)(degrees)) of PFDDs congeners. The relations of these thermodynamic parameters with the number and position of fluorine atom substitution (N(PFS)) were discussed, and it was found that there exist high correlations between thermodynamic parameters (entropy (S(degrees)), DeltaH(f)(degrees) and DeltaG(f)(degrees)) and N(PFS). According to the relative magnitude of their DeltaG(f)(degrees), the relative stability order of PFDD congeners was theoretically proposed.