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Previous cross-sectional and case–control studies have proposed that decreased vitamin D levels are positively correlated with the risk of suicidality in adults. However, limited studies have examined the association between vitamin D and suicidality in adolescents. This study aimed to investigate the relationship between serum vitamin D and suicidality risk among early adolescents.
Data were obtained from a Chinese early adolescent cohort. In this cohort, seventh-grade students from a middle school in Anhui Province were invited to voluntarily participate in the baseline assessments and provide peripheral blood samples (in September 2019). The participants were followed up annually (in September 2020 and September 2021). Serum 25-hydroxyvitamin D [25(OH)D] and vitamin D–related single-nucleotide polymorphisms at baseline were measured in November 2021. Traditional observational and Mendelian randomization (MR) analyses were performed to examine the relationship between serum 25(OH)D at baseline and the risk of baseline and incident suicidality (i.e., suicidal ideation [SI], plans and attempts).
Traditional observational analysis did not reveal a significant linear or non-linear association of serum 25(OH)D concentration with the risks of baseline and 2-year incident suicidality in the total sample (P > .05 for all). Sex-stratified analysis revealed a non-linear association between the 25(OH)D concentration and the risk of baseline SI in women (Poverall = .002; Pnon-linear = .001). Moreover, the risk of baseline SI in the 25(OH) insufficiency group was lower than that in the 25(OH) deficiency group in the total sample (odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.51–0.92, P = .012). This difference remained significant in women (OR = 0.59, 95% CI = 0.40–0.87, P = .008) but not in men (OR = 0.78, 95% CI = 0.53–1.15, P = .205). Additionally, both linear and non-linear MR analyses did not support the causal effect of serum 25(OH)D concentration on the risk of baseline, 1-year and 2-year incident suicidality (P > .05 for all).
This study could not confirm the causal effect of vitamin D on suicidality risk among Chinese early adolescents. Future studies must confirm these findings with a large sample size.
Research into neural mechanisms underlying cue-induced cigarette craving has attracted considerable attention for its significant role in treatments. However, there is little understanding about the effects of exposure to smoking-related cues on electroencephalogram (EEG) microstates of smokers, which can reflect abnormal brain network activity in several psychiatric disorders.
To explore whether abnormal brain network activity in smokers on exposure to smoking-related cues would be captured by EEG microstates.
Forty smokers were exposed to smoking and neutral imagery conditions (cues) during EEG recording. Behavioural data and parameters for microstate topographies associated with the auditory (A), visual (B), salience and memory (C) and dorsal attention networks (D) were compared between conditions. Correlations between microstate parameters and cigarette craving as well as nicotine addiction characteristics were also analysed.
The smoking condition elicited a significant increase in the duration of microstate classes B and C and in the duration and contribution of class D compared with the neutral condition. A significant positive correlation between the increased duration of class C (smoking minus neutral) and increased craving ratings was observed, which was fully mediated by increased posterior alpha power. The increased duration and contribution of class D were both positively correlated with years of smoking.
Our results indicate that smokers showed abnormal EEG microstates when exposed to smoking-related cues compared with neutral cues. Importantly, microstate class C (duration) might be a biomarker of cue-induced cigarette craving, and class D (duration and contribution) might reflect the relationship between cue-elicited activation of the dorsal attention network and years of smoking.
The goal of this meta-analysis is to evaluate the effects of exercise training on long-term health and cardiorespiratory fitness in participants with CHD after surgery and to investigate the optimal type of exercise training for post-operative patients and how to improve adherence to it.
We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Web of Science from the date of the inception of the database through August 2021.
Altogether, 1424 records were identified in the literature search. Studies evaluating outcomes between exercise training and usual care among post-operative patients with CHD were included. The assessed outcomes were quality of life and cardiorespiratory fitness. We analysed heterogeneity by using the I2 statistic and evaluated the evidence quality according to the recommendation by the Cochrane Collaboration. Nine randomised controlled trials were included. The evidence showed that exercise interventions increased peak oxygen consumption (mean difference = 2.29 [95% CI 0.43, 4.15]; p = 0.02, I2 = 0%). However, no differences in scores of health-related quality of life and pulmonary function were observed between the experimental and control groups.
In conclusion, participation in a physical exercise training programme was safe and improved fitness in patients after surgery for CHD. We recommend that post-operative patients with CHD participate in physical exercise training. Additional research is needed to study the various forms of exercise training and their impact on quality of life.
As the corona virus disease 2019 (COVID-19) pandemic continues around the world, understanding the transmission characteristics of COVID-19 is vital for prevention and control. We conducted the first study aiming to estimate and compare the relative risk of secondary attack rates (SARs) of COVID-19 in different contact environments. Until 26 July 2021, epidemiological studies and cluster epidemic reports of COVID-19 were retrieved from SCI, Embase, PubMed, CNKI, Wanfang and CBM in English and Chinese, respectively. Relative risks (RRs) were estimated in pairwise comparisons of SARs between different contact environments using the frequentist NMA framework, and the ranking of risks in these environments was calculated using the surface under the cumulative ranking curve (SUCRA). Subgroup analysis was performed by regions. Thirty-two studies with 68 260 participants were identified. Compared with meal or gathering, transportation (RR 10.55, 95% confidence interval (CI) 1.43–77.85), medical care (RR 11.68, 95% CI 1.58–86.61) and work or study places (RR 10.15, 95% CI 1.40–73.38) had lower risk ratios for SARs. Overall, the SUCRA rankings from the highest to the lowest were household (95.3%), meal or gathering (81.4%), public places (58.9%), daily conversation (50.1%), transportation (30.8%), medical care (18.2%) and work or study places (15.3%). Household SARs were significantly higher than other environments in the subgroup of mainland China and sensitive analysis without small sample studies (<100). In light of the risks, stratified personal protection and public health measures need to be in place accordingly, so as close contacts categorising and management.
The present study evaluated whether fat mass assessment using the triceps skinfold (TSF) thickness provides additional prognostic value to the Global Leadership Initiative on Malnutrition (GLIM) framework in patients with lung cancer (LC). We performed an observational cohort study including 2672 LC patients in China. Comprehensive demographic, disease and nutritional characteristics were collected. Malnutrition was retrospectively defined using the GLIM criteria, and optimal stratification was used to determine the best thresholds for the TSF. The associations of malnutrition and TSF categories with survival were estimated independently and jointly by calculating multivariable-adjusted hazard ratios (HR). Malnutrition was identified in 808 (30·2 %) patients, and the best TSF thresholds were 9·5 mm in men and 12 mm in women. Accordingly, 496 (18·6 %) patients were identified as having a low TSF. Patients with concurrent malnutrition and a low TSF had a 54 % (HR = 1·54, 95 % CI = 1·25, 1·88) greater death hazard compared with well-nourished individuals, which was also greater compared with malnourished patients with a normal TSF (HR = 1·23, 95 % CI = 1·06, 1·43) or malnourished patients without TSF assessment (HR = 1·31, 95 % CI = 1·14, 1·50). These associations were concentrated among those patients with adequate muscle mass (as indicated by the calf circumference). Additional fat mass assessment using the TSF enhances the prognostic value of the GLIM criteria. Using the population-derived thresholds for the TSF may provide significant prognostic value when used in combination with the GLIM criteria to guide strategies to optimise the long-term outcomes in patients with LC.
The coronavirus disease 2019 (COVID-19) epidemic is spreading globally. Studies revealed that obesity may affect the progression and prognosis of COVID-19 patients. The aim of the meta-analysis is to identify the prevalence and impact of obesity on COVID-19. Studies on obese COVID-19 patients were obtained by searching PubMed, Cochrane Library databases and Web of Science databases, up to date to 5 June 2020. And the prevalence rate and the odds ratio (OR) of obesity with 95% confidence interval (CI) were used as comprehensive indicators for analysis using a random-effects model. A total of 6081 patients in 11 studies were included. The prevalence of obesity in patients with COVID-19 was 30% (95% CI 21–39%). Obese patients were 1.79 times more likely to develop severe COVID-19 than non-obese patients (OR 1.79, 95% CI 1.52–2.11, P < 0.0001, I2 = 0%). However obesity was not associated with death in COVID-19 patients (OR 1.05, 95% CI 0.65–1.71, P = 0.84, I2 = 66.6%). In dose−response analysis, it was estimated that COVID-19 patients had a 16% increased risk of invasive mechanical ventilation (OR 1.16, 95% CI 1.10–1.23, P < 0.0001) and a 20% increased risk of admission to ICU (OR 1.20, 95% CI 1.11–1.30, P < 0.0001) per 5 kg/m2 increase in BMI. In conclusion, obesity in COVID-19 patients is associated with severity, but not mortality.
Association was found between tea and neural tube defects. However, few studies investigated the relationship between tea consumption and blood folate levels. We aimed to investigate the association between tea consumption and plasma folate concentrations among women aged 18–30 years in different ethnicities of China.
Data were obtained from a national cross-sectional study conducted from 2005 to 2006 of women aged 18–30 years in China. Socio-demographic characteristics and lifestyle were obtained from a questionnaire. Dietary folate intake was determined by 24-h dietary recall. Plasma folate concentrations were measured by a microbiological assay. Multiple linear regression model was used to calculate partial regression coefficients after adjusting for confounding factors.
Nine provinces or autonomous regions in China.
A total of 2932 women aged 18–30 years in China.
After stratifying by ethnicity and tea type, tea consumption was significantly positively associated with plasma folate levels in Han women who drank unfermented tea weekly (β = 0·067, and P = 0·037) or daily (β = 0·119, and P = 0·031) and in Uighur women who drank fermented tea weekly (β = 0·325, and P = 0·028). For women who drank unfermented tea in Han ethnicity, weekly and daily tea drinkers had 6·77 % (95 % CI: 6·36 %, 7·21 %) and 7·13 % (95 % CI: 6·40 %, 7·96 %) increase in plasma folate concentration compared with no tea drinkers.
There is a suggestion of possible positive association between unfermented tea drinking in Han ethnicity and plasma folate concentrations, for Chinese women aged 18–30 years. The relationship between tea drinking in other ethnic groups and plasma folate still needs to be further explored.
Not all plant-based and animal foods exert the same health effects due to their various nutrient compositions. We aimed to assess the quality of plant-based v. animal foods in relation to mortality in a prospective cohort study. Using data collected from a nationally representative sample of 36 825 adults in the National Health and Nutrition Examination Survey 1999–2014, we developed a de novo Comprehensive Diet Quality Index (cDQI) that assesses the quality of seventeen foods based on the healthfulness and separately scored the quality of eleven plant-based foods in a plant-based Diet Quality Index (pDQI) and six animal foods in an animal-based Diet Quality Index (aDQI). Mortality from all causes, heart disease and cancer were obtained from linkage to the National Death Index up to 31 December 2015. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95 % CI after multivariable adjustments. During a median follow-up of 8·3 years, 4669 all-cause deaths occurred, including 798 deaths due to heart disease and 1021 due to cancer. Compared with individuals in the lowest quartile, those in the highest quartile of cDQI had a lower risk of all-cause mortality (HR 0·75, 95 % CI 0·65, 0·86; Ptrend < 0·001), which largely reflected the inverse relationship between quality of plant-based foods (pDQI) and all-cause mortality (HR 0·66, 95 % CI 0·58, 0·74; Ptrend < 0·001). No independent association was found for the quality of animal foods (aDQI) and mortality. Our results suggest that consuming healthy plant-based foods is associated with lower all-cause mortality among US adults.
We study bundles on projective spaces that have vanishing lower cohomologies using their short minimal free resolutions. We partition the moduli
according to the Hilbert function H and classify all possible Hilbert functions H of such bundles. For each H, we describe a stratification of
by quotients of rational varieties. We show that the closed strata form a graded lattice given by the Betti numbers.