Understanding the role of children in the transmission of SARS-CoV-2 is urgently required given its policy implications in relation to the reopening of schools and intergenerational contacts.
We ...conducted a rapid review of studies that investigated the role of children in the transmission of SARS-CoV-2. We synthesized evidence for four categories: 1) studies reporting documented cases of SARS-CoV-2 transmission by infected children; 2) studies presenting indirect evidence on the potential of SARS-CoV-2 transmission by (both symptomatic and asymptomatic) children; 3) studies reporting cluster outbreaks of COVID-19 in schools; 4) studies estimating the proportions of children infected by SARS-CoV-2, and reported results narratively.
A total of 16 unique studies were included for narrative synthesis. There is limited evidence detailing transmission of SARS-CoV-2 from infected children. We found two studies that reported a 3-month-old whose parents developed symptomatic COVID-19 seven days after caring for the infant and two children who may have contracted COVID-19 from the initial cases at a school in New South Wales. In addition, we identified six studies presenting indirect evidence on the potential for SARS-CoV-2 transmission by children, three of which found prolonged virus shedding in stools. There is little data on the transmission of SARS-CoV-2 in schools. We identified only two studies reporting outbreaks of COVID-19 in school settings and one case report of a child attending classes but not infecting any other pupils or staff. Lastly, we identified six studies estimating the proportion of children infected; data from population-based studies in Iceland, Italy, South Korea, Netherlands, California and a hospital-based study in the UK suggest children may be less likely to be infected.
Preliminary results from population-based and school-based studies suggest that children may be less frequently infected or infect others, however current evidence is limited. Prolonged faecal shedding observed in studies highlights the potentially increased risk of faeco-oral transmission in children. Further seroprevalence studies (powered adequately for the paediatric population) are urgently required to establish whether children are in fact less likely to be infected compared to adults.
We plan to update this rapid review as new data becomes available. These updates are available at https://www.ed.ac.uk/usher/uncover/completed-uncover-reviews.
Full text
Available for:
NUK, OILJ, UL, UM, UPUK, VSZLJ
A growing body of evidence suggests that vitamin D deficiency has been associated with an increased susceptibility to viral and bacterial respiratory infections. In this study, we aimed to examine ...the association between vitamin D and COVID-19 risk and outcomes. We used logistic regression to identify associations between vitamin D variables and COVID-19 (risk of infection, hospitalisation and death) in 417,342 participants from UK Biobank. We subsequently performed a Mendelian Randomisation (MR) study to look for evidence of a causal effect. In total, 1746 COVID-19 cases (399 deaths) were registered between March and June 2020. We found no significant associations between COVID-19 infection risk and measured 25-OHD levels after adjusted for covariates, but this finding is limited by the fact that the vitamin D levels were measured on average 11 years before the pandemic. Ambient UVB was strongly and inversely associated with COVID-19 hospitalization and death overall and consistently after stratification by BMI and ethnicity. We also observed an interaction that suggested greater protective effect of genetically-predicted vitamin D levels when ambient UVB radiation is stronger. The main MR analysis did not show that genetically-predicted vitamin D levels are causally associated with COVID-19 risk (OR = 0.77, 95% CI 0.55-1.11, P = 0.160), but MR sensitivity analyses indicated a potential causal effect (weighted mode MR: OR = 0.72, 95% CI 0.55-0.95, P = 0.021; weighted median MR: OR = 0.61, 95% CI 0.42-0.92, P = 0.016). Analysis of MR-PRESSO did not find outliers for any instrumental variables and suggested a potential causal effect (OR = 0.80, 95% CI 0.66-0.98, p-val = 0.030). In conclusion, the effect of vitamin D levels on the risk or severity of COVID-19 remains controversial, further studies are needed to validate vitamin D supplementation as a means of protecting against worsened COVID-19.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Spontaneous isolated celiac artery dissection (SICAD) and spontaneous isolated superior mesenteric artery dissection (SISMAD) represent the major types of spontaneous visceral artery dissection. ...However, no quantitative meta-analysis of SICAD and SISMAD is available. The aim of our study was to pool current evidence concerning basic profiles, treatment strategies, long-term adverse events, and morphologic changes of lesioned vessels in SICAD and SISMAD patients.
We searched the MEDLINE, Embase, Scopus, and Cochrane Databases (January 1, 1946-September 21, 2017) for studies of SICAD and SISMAD. Related cohort studies or case series with sample size larger than 10 were included. Two reviewers independently extracted and summarized the data. A random-effects model was used to calculate pooled estimates.
In total, 43 studies were included. An estimated 8% (95% confidence interval CI, 0.01-0.21) symptomatic SICAD and 12% (95% CI, 0.06-0.19) symptomatic SISMAD patients with initial conservative management required secondary intervention during follow-up, whereas none of the asymptomatic patients treated conservatively required secondary intervention. As for morphologic changes during follow-up, a higher proportion of SICAD patients (64%; 95% CI, 0.47-0.80) achieved complete remodeling compared with SISMAD patients (25%; 95% CI, 0.19-0.32), and an estimated 6% (95% CI, 0.00-0.16) of SICAD and 12% (95% CI, 0.05-0.20) of SISMAD patients had morphologic progression. Overall, the pooled estimate of long-term all-cause mortality was 0% (95% CI, 0.00-0.03) in SICAD and 1% (95% CI, 0.00-0.02) in SISMAD. When stratified by symptoms, symptomatic patients were associated with a significantly increased probability of accomplishing complete remodeling (odds ratio, 3.95; 95% CI, 1.31-11.85) compared with asymptomatic patients.
Initial conservative treatment is safe for asymptomatic SICAD or SISMAD patients. Symptomatic patients managed conservatively have relatively high occurrence of late secondary intervention, which may require closer surveillance, especially in SISMAD because of a lower rate of remodeling.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Substantial evidence indicates that dysbiosis of the gut microbial community is associated with colorectal neoplasia. This review aims to systematically summarise the microbial markers associated ...with colorectal neoplasia and to assess their predictive performance.
A comprehensive literature search of MEDLINE and EMBASE databases was performed to identify eligible studies. Observational studies exploring the associations between microbial biomarkers and colorectal neoplasia were included. We also included prediction studies that constructed models using microbial markers to predict CRC and adenomas. Risk of bias for included observational and prediction studies was assessed.
Forty-five studies were included to assess the associations between microbial markers and colorectal neoplasia. Nine faecal microbiotas (i.e., Fusobacterium, Enterococcus, Porphyromonas, Salmonella, Pseudomonas, Peptostreptococcus, Actinomyces, Bifidobacterium and Roseburia), two oral pathogens (i.e., Treponema denticola and Prevotella intermedia) and serum antibody levels response to Streptococcus gallolyticus subspecies gallolyticus were found to be consistently associated with colorectal neoplasia. Thirty studies reported prediction models using microbial markers, and 83.3% of these models had acceptable-to-good discrimination (AUROC > 0.75). The results of predictive performance were promising, but most of the studies were limited to small number of cases (range: 9-485 cases) and lack of independent external validation (76.7%).
This review provides insight into the evidence supporting the association between different types of microbial species and their predictive value for colorectal neoplasia. Prediction models developed from case-control studies require further external validation in high-quality prospective studies. Further studies should assess the feasibility and impact of incorporating microbial biomarkers in CRC screening programme.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The role of urate in cardiovascular diseases (CVDs) has been extensively investigated in observational studies; however, the extent of any causal effect remains unclear, making it difficult to ...evaluate its clinical relevance.
A phenome-wide association study (PheWAS) together with a Bayesian analysis of tree-structured phenotypic model (TreeWAS) was performed to examine disease outcomes related to genetically determined serum urate levels in 339,256 unrelated White British individuals (54% female) in the UK Biobank who were aged 40-69 years (mean age, 56.87; SD, 7.99) when recruited from 2006 to 2010. Mendelian randomization (MR) analyses were performed to replicate significant findings using various genome-wide association study (GWAS) consortia data. Sensitivity analyses were conducted to examine possible pleiotropic effects on metabolic traits of the genetic variants used as instruments for urate. PheWAS analysis, examining the association with 1,431 disease outcomes, identified 13 distinct phecodes representing 4 disease groups (inflammatory polyarthropathies, hypertensive disease, circulatory disease, and metabolic disorders) and 9 disease outcomes (gout, gouty arthropathy, pyogenic arthritis, essential hypertension, coronary atherosclerosis, ischemic heart disease, chronic ischemic heart disease, myocardial infarction, and hypercholesterolemia) that were associated with genetically determined serum urate levels after multiple testing correction (p < 3.35 × 10-4). TreeWAS analysis, examining 10,750 ICD-10 diagnostic terms, identified more sub-phenotypes of cardiovascular and cerebrovascular diseases (e.g., angina pectoris, heart failure, cerebral infarction). MR analysis successfully replicated the association with gout, hypertension, heart diseases, and blood lipid levels but indicated the existence of genetic pleiotropy. Sensitivity analyses support an inference that pleiotropic effects of genetic variants on urate and metabolic traits contribute to the observational associations with CVDs. The main limitations of this study relate to possible bias from pleiotropic effects of the considered genetic variants and possible misclassification of cases for mild disease that did not require hospitalization.
In this study, high serum urate levels were found to be associated with increased risk of different types of cardiac events. The finding of genetic pleiotropy indicates the existence of common upstream pathological elements influencing both urate and metabolic traits, and this may suggest new opportunities and challenges for developing drugs targeting a common mediator that would be beneficial for both the treatment of gout and the prevention of cardiovascular comorbidities.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Despite a burgeoning literature during the last two decades regarding perioperative risk management of anal fistula, little is known about its risk factors that influence postoperative recurrence. We ...performed a meta-analysis to summarize and assess the credibility of evidence of potential risk factors for anal fistula recurrence (AFR) after surgery.
Pubmed and EMBASE without language restriction were searched from inception to April 2018 that reported risk factors which predisposed recurrence after anal fistula surgery. We excluded studies that involved patients with anal fistula associated with Crohn's disease. MOOSE guidelines were followed when this meta-analysis was performed. We used random-effects models to pool relative risks (RRs) with 95% confidence intervals (CIs). Evidence from observational studies was graded into high-quality (Class I), moderate-quality (Class II/III) and low-quality (Class IV) based on Egger's P value, total sample size and between-study heterogeneity.
Of 3514 citations screened, 20 unique observational studies comprising 6168 patients were involved in data synthesis. High-quality evidence showed that AFR was associated with high transsphincteric fistula (RR, 4.77; 95% CI, 3.83 to 5.95), internal opening unidentified (RR, 8.54; 95% CI, 5.29 to 13.80), and horseshoe extensions (RR, 1.92; 95% CI, 1.43 to 2.59). Moderate-quality evidence suggested an association with prior anal surgery (RR, 1.52; 95% CI, 1.04 to 2.23), seton placement surgery (RR, 2.97; 95% CI, 1.10 to 8.06), and multiple fistula tract (RR, 4.77; 95% CI, 1.46 to 15.51). High-quality evidence demonstrated no significant association with gender or smoking; moderate-quality evidence also suggested no association with age, tertiary referral, alcohol use, diabetes mellitus, obesity, preoperative seton drainage, high internal opening, postoperative drainage, mucosal advancement flap surgery, supralevator extensions, location or type of anal fistula.
Several patient, surgery and fistula-related factors are significantly associated with postoperative AFR. These findings strengthen clinical awareness of early warning to identify patients with high-risk disease recurrence for AFR.
•No meta-analysis has been conducted to summarize the credibility of evidence of risk factors for AFR after surgery.•This meta-analysis finds that several risk factors are significantly associated with AFR with different quality of evidence.•These findings strengthen clinical awareness of early warning to identify patients with high risk for AFR.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There is a clear need for systematic appraisal of models/factors predicting colorectal cancer (CRC) metastasis and recurrence because clinical decisions about adjuvant treatment are taken on the ...basis of such variables.
We conducted an umbrella review of all systematic reviews of observational studies (with/without meta-analysis) that evaluated risk factors of CRC metastasis and recurrence. We also generated an updated synthesis of risk prediction models for CRC metastasis and recurrence. We cross-assessed individual risk factors and risk prediction models.
Thirty-four risk factors for CRC metastasis and 17 for recurrence were investigated. Twelve of 34 and 4/17 risk factors with p < 0.05 were estimated to change the odds of the outcome at least 3-fold. Only one risk factor (vascular invasion for lymph node metastasis LNM in pT1 CRC) presented convincing evidence. We identified 24 CRC risk prediction models. Across 12 metastasis models, six out of 27 unique predictors were assessed in the umbrella review and four of them changed the odds of the outcome at least 3-fold. Across 12 recurrence models, five out of 25 unique predictors were assessed in the umbrella review and only one changed the odds of the outcome at least 3-fold.
This study provides an in-depth evaluation and cross-assessment of 51 risk factors and 24 prediction models. Our findings suggest that a minority of influential risk factors are employed in prediction models, which indicates the need for a more rigorous and systematic model construction process following evidence-based methods.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Display omitted
•This work concentrates on providing the theoretical basis and process optimization scheme of the laser powder bed fusion (LPBF) in situ alloying technology to prepare novel high ...entropy alloy.•A micro-scale integrated simulation model is constructed based on the discrete element method (DEM), finite element method (FEM), and calculation of phase diagram (CALPHAD).•Equi-atomic FeCoCrNi medium entropy alloy is used as the model alloy, the forming performance are predicted by the integrated simulation model output and the print experiments.•The heterogeneous powder bed cannot fully be alloyed under the traditional laser scanning parameters, a laser remelting process is indispensable to improve the composition inhomogeneity of final part.
The Laser Powder Bed Fusion (LPBF) in-situ alloying is a novel technology for preparing novel alloys efficiently. However, the narrow process window limit its application. A micro-scale integrated simulation model is designed and constructed based on the Discrete Element Method (DEM), the Finite Element Method (FEM), and Calculation of phase diagram (CALPHAD) method in the work. The equation of the methods are introduced. By defining the parameters such as composition inhomogeneity ω, the forming performance of LPBF in-situ alloying FeCoCrNi medium entropy alloys are predicted. The calculation results show that the hysteresis diffusion effect makes the mixing powders more challenging to be in-situ alloyed than conventional main component alloys. For the mixed powder beds consisting of 15–53 μm particles with equal mass ratio, the composition deviation on the micro-scale is within 2.5%, and the composition homogeneity reaches 98.9 %. Under a laser power of 150 W and a scanning speed of 500 mm/s, several laser remelting process are indispensable to eliminate unmelted elements. Experiments are carried out to verify the accuracy of the integrated simulation model, and the high-efficiency preparation experiment of non-equiatomic ratio medium entropy alloy was carried out by using the technology.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
BACKGROUND:There has been a long-lasting controversy about whether higher BMI is associated with worse perioperative outcomes of laparoscopic colorectal surgery. Recently, a number of newly published ...investigations have made it possible to draw a quantitative conclusion.
OBJECTIVE:We conducted this comprehensive meta-analysis to clarify the exact effect that BMI imposes on perioperative outcome of laparoscopic colorectal surgery.
DATA SOURCES:We systematically searched MEDLINE, Embase, and Cochrane Library databases to identify all relevant studies.
STUDY SELECTION:Comparative studies in English that investigated perioperative outcome of laparoscopic colorectal surgery for patients with different BMIs were included. Quality of studies was evaluated by using the Newcastle-Ottawa Scale.
INTERVENTION:The risk factor of interest was BMI.
MAIN OUTCOME MEASURES:Effective sizes were pooled under a random-effects model to evaluate preoperative, intraoperative, and postoperative outcomes.
RESULTS:A total of 43 studies were included. We found that higher BMI was associated with significantly longer operative time (p < 0.001), greater blood loss (p = 0.01), and higher incidence of conversion to open surgery (p < 0.001). Moreover, BMI was a risk factor for overall complication rates (p < 0.001), especially for ileus (p = 0.02) and events of the urinary system (p = 0.03). Significant association was identified between higher BMI and risk of surgical site infection (p < 0.001) and anastomotic leakage (p = 0.02). Higher BMI might also led to a reduced number of harvest lymph nodes for patients with colorectal cancer (p = 0.02). The heterogeneity test identified no significant cross-study heterogeneity, and the results of cumulative meta-analysis, sensitivity analysis, and the publication bias test verified the reliability of our study.
LIMITATIONS:Most studies included were retrospectively designed.
CONCLUSIONS:Body mass index is a practical and valuable measurement for the prediction of the perioperative outcome of laparoscopic colorectal surgery. Higher BMI is associated with worse perioperative outcome. More accurate conclusions, with more precise cutoff values, can be achieved by future well-designed prospective investigations.
1 To understand the trends of overweight and obesity in China, we accessed the country/territory-level year-specific data of age-standardized summary exposure value (SEV, standing for the pooled ...proportion among the population), deaths, and disability-adjusted life of years (DALYs) for high body mass index (BMI, high BMI was defined as the BMI level higher than theoretical minimum risk exposure level 25 kg/m2) and its associated diseases for 204 countries/territories between 1990 and 2019 using data from the Global Burden of Disease Collaborative Network. Health care providers call for trustworthy and transparent evidence-based clinical practice guidelines to facilitate their practice of bodyweight control. 7.Shi, QWang, YHao, QVandvik, POGuyatt, GLi, J. Pharmacotherapy for adults with overweight and obesity: a systematic review and network meta-analysis of randomised controlled trials. 8.Ge, LSadeghirad, BBall, GDCda Costa, BRHitchcock, CLSvendrovski, A. Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials.