Search

Sparse code multiple access (SCMA) is a promising technology to provide high throughput and overall improved system performance at affordable cost for next-generation passive optical networks (NG-PONs). Message passing algorithm (MPA) based on a factor graph is usually used for low-complexity multi-user detection in SCMA. However, MPA requires accurate and effective channel estimation due to the interference between the user's signals on the same resource block and suffers uncertain convergence caused by the cycles in the factor graph. In this paper, a graph neural networks (GNN)-based detection method is proposed for SCMA-PON, which performs channel impairment compensation and signal detection in a joint manner. 25.5 Gb/s SCMA-OFDM system over 20/60 km single mode fiber link is simulated to demonstrate the feasibility with 8.5-G class optical devices. The simulation results show that GNN-based detection method outperforms MPA and is more robust to the nonlinear distortion for the same level of computational complexity.

Background The effect of hormone replacement therapy (HRT) on colorectal cancer (CRC) mortality and all-cause mortality remains unclear. We conducted a systematic review and dose‒response meta-analysis to determine the effects of HRT on CRC mortality and all-cause mortality. Methods We searched the PubMed, Embase, and Cochrane Library electronic databases for all relevant studies published until June 2022 to investigate the effects of HRT exposure on survival rates for patients with CRC. Two reviewers independently extracted individual study data and evaluated THE risk of bias among the studies using the Newcastle‒Ottawa Scale. To examine a potential nonlinear relationship between the year of HRT use and CRC mortality, we performed a two-stage random effects dose‒response meta-analysis. RESULTS Ten cohort studies encompassing 480,628 individuals were included. The meta-analysis revealed that HRT was inversely associated with the risk of CRC mortality [hazard ratios (HR) = 0.77, 95% CI (0.68, 0.87), I2 = 69.5%, P 2 = 89.6%, p

Objectives: To identify reporting guidelines related to surgical technique and propose recommendations for areas that require improvement. Study Design and Setting: A protocol-guided scoping review was conducted. A literature search of MEDLINE, the EQUATOR Network Library, Google Scholar, and Networked Digital Library of Theses and Dissertations was conducted to identify surgical technique reporting guidelines published up to December 31, 2021. Results: We finally included 55 surgical technique reporting guidelines, vascular surgery (n = 18, 32.7%) was the most common among the clinical specialties covered. The included guidelines generally showed a low degree of international and multidisciplinary cooperation. Few guidelines provided a detailed development process (n = 14, 25.5%), conducted a systematic literature review (n = 13, 23.6%), used the Delphi method (n = 4, 7.3%), or described post-publication strategy (n = 6, 10.9%). The vast majority guidelines focused on the reporting of intraoperative period (n = 50, 90.9%). However, of the guidelines requiring detailed descriptions of surgical technique methodology (n = 43, 78.2%), most failed to provide guidance on what constitutes an adequate description. Conclusion: Our study demonstrates significant deficiencies in the development methodology and practicality of reporting guidelines for surgical technique. A standardized reporting guideline that is developed rigorously and focuses on details of surgical technique may serve as a necessary impetus for change.

Objective To analyze the retraction status and reasons of non-Cochrane systematic reviews (SRs) in medicine. Study Design and Setting MEDLINE, Embase, Retraction Watch Database and Google Scholar were systematically searched to find all retracted non-Cochrane SRs. Results Of 159 non-Cochrane SRs in medicine retracted between 2004 and 2020, more than 70% were led by authors from China and affiliated with hospitals. The largest proportion of retraction notices were issued by the publisher and editor(s) jointly. Fraudulent peer-review was the most common reason for retraction, followed by unreliable data meaning errors in study selection or data analysis. The median time between publication and retraction was 14 months, and SRs retracted due to research misconduct took longer to retract than honest error. Conclusion The total number of retracted SRs is increasing worldwide, in particular in China. The most common reasons for retraction are fraudulent peer-review and unreliable data, and in most cases the SR is retracted more than a year after publication. Better systems of ethical oversight and culture to improve the process of peer review and adherence to the COPE retraction guidance are needed, and authors should strengthen their skills in SR methodology.

BACKGROUND: The reporting of surgical techniques is of mixed quality, with most at a very minimal level. Reporting guidelines that could be applied to guide surgical technique reporting vary in methodology for development, discipline coverage, dimension coverage and detail requested. However, a scoping review that could indicate the gaps and efforts needed in surgical technique reporting guidelines is lacking and warranted. This study aims to design a methodological rigour protocol to guide the development of a scoping review of surgical technique reporting guidelines. METHODS: This protocol is designed following the 2020 manual proposed by the Joanna Briggs Institute. To further ensure the soundness of the protocol, we also included multidisciplinary professionals (including methodologists, clinicians, and journal editors) to refine the protocol. DISCUSSION: Seven key steps for developing the scoping review are identified and presented in detail, including (I) identifying the research questions; (II) inclusion criteria; (III) search strategy; (IV) source of evidence selection; (V) data extraction; (VI) analysis of the evidence; and (VII) presentation of the results. Guided by this protocol, the subsequent scoping review will inform us the overview of surgical technique reporting guidelines and precisely guide our direction and next steps in improving surgical technique reporting guidelines. TRIAL REGISTRATION: This protocol is not registered as the PROSPERO database only accepts registration of systematic review protocols while does not accept registration of scoping review protocols. ispartof: GLAND SURGERY vol:10 issue:7 pages:2325-2333 ispartof: location:China (Republic : 1949- ) status: published

Objective Since the beginning of the COVID‐19 epidemic, a large number of guidelines on diagnosis and treatment of COVID‐19 have been developed, but the quality of those guidelines and the consistency of recommendations are unclear. The objective of this study is to evaluate the quality of the diagnosis and treatment guidelines on COVID‐19 and analyze the consistency of the recommendations of these guidelines. Methods We searched for guidelines on diagnosis and/or treatment of COVID‐19 through PubMed, CBM, CNKI, and WanFang Data, from January 1, 2020 to August 31, 2020. In addition, we also searched official websites of the US CDC, European CDC and WHO, and some guideline collection databases. We included diagnosis and/or treatment guidelines for COVID‐19, including rapid advice guidelines and interim guidelines. Two trained researchers independently extracted data and four trained researchers evaluated the quality of the guidelines using the AGREE II instruments. We extracted information on the basic characteristics of the guidelines, guideline development process, and the recommendations. We described the consistency of the direction of recommendations for treatment and diagnosis of COVID‐19 across the included guidelines. Results A total of 37 guidelines were included. Most included guidelines were assessed as low quality, with only one of the six domains of AGREE II (clarity of presentation) having a mean score above 50%. The mean scores of three domains (stakeholder involvement, the rigor of development and applicability) were all below 30%. The recommendations on diagnosis and treatment were to some extent consistent between the included guidelines. Computed tomography (CT), X‐rays, lung ultrasound, RT‐PCR, and routine blood tests were the most commonly recommended methods for COVID‐19 diagnosis. Thirty guidelines were on the treatment of COVID‐19. The recommended forms of treatment included supportive care, antiviral therapy, glucocorticoid therapy, antibiotics, immunoglobulin, extracorporeal membrane oxygenation (ECMO), convalescent plasma, and psychotherapy. Conclusions The methodological quality of currently available diagnosis and treatment guidelines for COVID‐19 is low. The diagnosis and treatment recommendations between the included guidelines are highly consistent. The main diagnostic methods for COVID‐19 are RT‐PCR and CT, with ultrasound as a potential diagnostic tool. As there is no effective treatment against COVID‐19 yet, supportive therapy is at the moment the most important treatment option.

Plant-soil microbe linkage is theoretically positive, but rarely observed in natural ecosystems. We hypothesized that animal grazing decouples this linkage, for plant removal usually decreases plant influences on soil microbiota. We tested the hypothesis by exploring plant and soil microbial diversity in grazed versus non-grazed grasslands along a gradient of plant diversity. Grazing slightly decreased the diversity of plants and soil microbes in high-diversity sites, but increased them in low-diversity sites. Plant and microbial diversity positively correlated in non-grazed grasslands (P < 0.001), but not in grazed grasslands, indicating that grazing decoupled the biodiversity linkage. The decoupling was attributed to the change of the principal driver of soil microbiota from plant variables in non-grazed grasslands to soil variables in grazed grasslands. The diversity decoupling was also characterized by reduced plant-microbe interactions and lower heterogeneity in grazed grasslands. Our findings provide significant insights into the cross-biota linkages in grassland ecosystems.

Coronavirus disease 2019 (COVID-19) has rapidly spread worldwide, but there is so far no comprehensive analysis of all known symptoms of the disease. Our study aimed to present a comprehensive picture of the clinical symptoms of COVID-19 using an evidence map.We systematically searched MEDLINE via PubMed, Web of Science, Embase, and Cochrane library from their inception to March 16, 2021. We included systematic reviews reporting the clinical manifestations of COVID-19 patients. We followed the PRISMA guidelines, and the study selection, data extraction, and quality assessment were done by two individuals independently. We assessed the methodological quality of the studies using AMSTAR. We visually presented the clinical symptoms of COVID-19 and their prevalence.A total of 102 systematic reviews were included, of which, 68 studies (66.7%) were of high quality, 19 studies (18.6%) of medium quality, and 15 studies (14.7%) of low quality. We identified a total of 74 symptoms including 17 symptoms of the respiratory system, 21 symptoms of the neurological system, 10 symptoms of the gastrointestinal system, 16 cutaneous symptoms, and 10 ocular symptoms. The most common symptoms were fever (67 studies, ranging 16.3%-91.0%, pooled prevalence: 64.6%, 95%CI, 61.3%-67.9%), cough (68 studies, ranging 30.0%-72.2%, pooled prevalence: 53.6%, 95%CI, 52.1%-55.1%), muscle soreness (56 studies, ranging 3.0%-44.0%, pooled prevalence: 18.7%, 95%CI, 16.3%-21.3%), and fatigue (52 studies, ranging 3.3%-58.5%, pooled prevalence: 29.4%, 95%CI, 27.5%-31.3%). The prevalence estimates for COVID-19 symptoms were generally lower in neonates, children and adolescents, and pregnant women than in the general populations.At least 74 different clinical manifestations are associated with COVID-19. Fever, cough, muscle soreness, and fatigue are the most common, but attention should also be paid to the rare symptoms that can help in the early diagnosis of the disease.

Objective To assess the methodological and reporting quality of Chinese- and English -language systematic reviews and meta-analyses (SRs/MAs) published by Chinese authors between 2016 and 2018. Study Design and Setting We searched MEDLINE and Chinese Science Citation Database (CSCD) for SRs/MAs led by Chinese authors published between 2016 and 2018. We used random sampling to select 10% of the eligible SRs/MAs published in each year from CSCD, and then matched the same number of SRs/MAs in MEDLINE. Reporting quality was evaluated using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and methodological quality using the Assessment of Multiple Systematic Reviews (AMSTAR-2) tool. Stratified analyses were conducted to compare the differences of quality between Chinese- and English language SRs/MAs. Results We identified 336 SRs/MAs (168 in Chinese and 168 in English). The reporting quality in Chinese-language SRs/MAs was slightly lower than English-language SRs/MAs (mean PRISMA scores: 20.58 vs. 21.71 in 2016, 19.87 vs. 21.24 in 2017, and 21.29 vs. 22.38 in 2018). Less than half of both Chinese- and English-language SRs/MAs complied with item 5 (protocol and registration), item 7 (information sources), item 8 (search) and item 27 (funding)). The methodological quality in Chinese -language SRs/MAs was also slightly lower than English -language SRs/MAs (mean AMSTAR-2 scores: 8.07 vs. 9.36 in 2016; 9.21 vs. 10.26 in 2017; 8.86 vs. 9.28 in 2018). Three items (item 2: established a protocol; item 4: use a comprehensive literature search; and item 10: report the sources of funding) were adhered to by less than 10% of both Chinese- and English -language SRs/MAs. Only one (0.6%) Chinese-language SRs/MA and nine (5.4%) English-language SRs/MAs were rated as high methodological quality. Conclusion The reporting and methodological quality of English-language SRs/MAs conducted by authors from China between 2016 and 2018 were slightly better than those of Chinese -language SRs/MAs.

Background . Hundreds of coronavirus disease 2019 (COVID-19) clinical practice guidelines (CPGs) and expert consensus statements have been developed and published since the outbreak of the epidemic. However, these CPGs are of widely variable quality. So, this review is aimed at systematically evaluating the methodological and reporting qualities of COVID-19 CPGs, exploring factors that may influence their quality, and analyzing the change of recommendations in CPGs with evidence published. Methods . We searched five electronic databases and five websites from 1 January to 31 December 2020 to retrieve all COVID-19 CPGs. The assessment of the methodological and reporting qualities of CPGs was performed using the AGREE II instrument and RIGHT checklist. Recommendations and evidence used to make recommendations in the CPGs regarding some treatments for COVID-19 (remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir) were also systematically assessed. And the statistical inference was performed to identify factors associated with the quality of CPGs. Results . We included a total of 92 COVID-19 CPGs developed by 19 countries. Overall, the RIGHT checklist reporting rate of COVID-19 CPGs was 33.0%, and the AGREE II domain score was 30.4%. The overall methodological and reporting qualities of COVID-19 CPGs gradually improved during the year 2020. Factors associated with high methodological and reporting qualities included the evidence-based development process, management of conflicts of interest, and use of established rating systems to assess the quality of evidence and strength of recommendations. The recommendations of only seven (7.6%) CPGs were informed by a systematic review of evidence, and these seven CPGs have relatively high methodological and reporting qualities, in which six of them fully meet the Institute of Medicine (IOM) criteria of guidelines. Besides, a rapid advice CPG developed by the World Health Organization (WHO) of the seven CPGs got the highest overall scores in methodological (72.8%) and reporting qualities (83.8%). Many CPGs covered the same clinical questions (it refers to the clinical questions on the effectiveness of treatments of remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir in COVID-19 patients) and were published by different countries or organizations. Although randomized controlled trials and systematic reviews on the effectiveness of treatments of remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir for patients with COVID-19 have been published, the recommendations on those treatments still varied greatly across COVID-19 CPGs published in different countries or regions, which may suggest that the CPGs do not make sufficient use of the latest evidence. Conclusions . Both the methodological and reporting qualities of COVID-19 CPGs increased over time, but there is still room for further improvement. The lack of effective use of available evidence and management of conflicts of interest were the main reasons for the low quality of the CPGs. The use of formal rating systems for the quality of evidence and strength of recommendations may help to improve the quality of CPGs in the context of the COVID-19 pandemic. During the pandemic, we suggest developing a living guideline of which recommendations are supported by a systematic review for it can facilitate the timely translation of the latest research findings to clinical practice. We also suggest that CPG developers should register the guidelines in a registration platform at the beginning for it can reduce duplication development of guidelines on the same clinical question, increase the transparency of the development process, and promote cooperation among guideline developers all over the world. Since the International Practice Guideline Registry Platform has been created, developers could register guidelines prospectively and internationally on this platform.

BACKGROUND: Standardized and transparent reporting of surgical technique is the cornerstone of effective dissemination, implementation and improvement. However, current reporting of surgical techniques is inadequate. The existing guidelines potentially applied to guide surgical technique reporting are with a minimal highlight of the surgical technique, lack requirements explaining what extent and dimensions need to be described in detail, or are unlikely to extrapolate to a wide range of surgical techniques. This study aims to formulate a rigorous protocol to develop a surgical technique reporting checklist and standards (SUPER) that defines what a clear, comprehensive and detailed surgical technique report should be contained. METHODS: This protocol is designed following the classic guidance for developing reporting guidelines recommended by the EQUATOR network. RESULTS: The development team will consist of surgeons (~80%), methodologists, and journal editors. The draft checklist sources will include a scoping review of existing reporting guidelines related to surgical technique, surgical technique articles from 15 top journals published in the last year, and brainstorming by the multidisciplinary development team. The final SUPER checklist will be formed after three rounds of Delphi surveys, one round of face-to-face meeting, and a month-long pilot test. The SUPER checklist will be published as open-access and be used in combination with existing reporting guidelines related to surgical techniques (e.g., IDEAL). This protocol will steer the SUPER checklist's development, allowing us to further elaborate surgical technique reporting for all surgical specialties, and enabling a more favorable experience for surgeons, nurses, medical students, residents, editors, and reviewers. TRIAL REGISTRATION: This trial is registered at the EQUATOR network on December 18th, 2020. Available at: https://www.equator-network.org/library/reporting-guidelines-under-development/reporting-guidelines-under-development-for-other-study-designs/. ispartof: GLAND SURGERY vol:10 issue:8 pages:2591-2599 ispartof: location:China (Republic : 1949- ) status: published

Polypharmacy and related adverse consequences are common in the older adults, especially mortality, but the causality of this relationship remains unclear. This meta-analysis aimed to explore the relationship between polypharmacy and mortality in older adults.We systematically searched Pubmed, Embase, and the Cochrane Library from inception until August 2021 to identify observational studies providing quantitative estimates on the association between polypharmacy(≥5drugs) and mortality in the elderly (≥65 years). Results from individual studies were pooled using a random-effects or fixed-effects model.A total of twenty-four cohort studies including 2,967,952 participants of 65 years or older in this meta-analysis. twenty-four studies found a significant increase in mortality associated with polypharmacy (≥5 drugs) [Relative Risk, RR=1.28, 95%CI (1.19,1.39), P0.05] or excessive polypharmacy (≥10 drugs) [Relative Risk, RR=1.44, 95%CI (1.03,2.01), P0.05] among older adults. Eight studies showed an 50% increased hospitalization rate for polypharmacy in the older adults [RR=1.50, 95%CI (1.18,1.89), P0.05]. Subgroup analysis showed that the relationship between polypharmacy and mortality was different among older adults in community [RR=1.41, 95%CI (1.24,1.60), P0.05], in hospital [RR=1.10, 95%CI (1.00,1.20), P0.05], in institutions [RR=1.47, 95%CI (1.29,1.68), P0.05]. The mortality rate of the elderly using 5 to 9 drugs was [RR=1.23, 95%CI (1.06,1.43), P0.05] and using more than 10 drugs was [RR=1.44, 95%CI (1.03,2.01), P0.05].The results of this meta-analysis suggest that polypharmacy may be associated with increased mortality in older adults, but this association must be carefully considered and needed further validation.CI=confidence interval; MOOSE=Meta-analysis of Observational Studies in Epidemiology; NOS = Newcastle-Ottawa Scale; PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RR = relative risk; HR = hazard ratio; OR = odds ratio; GRADE = Grading of Recommendations Assessment Development and Evaluation.

Background: Gallbladder drainage plays a key role in the management of acute cholecystitis (AC) patients. Percutaneous transhepatic gallbladder drainage (PTGBD) is commonly used while endoscopic naso-gallbladder drainage (ENGBD) serves as an alternative. Methods: A single center, prospective randomized controlled trial was performed. Eligible AC patients were randomly assigned to ENGBD or PTGBD group. Randomization was a computer-generated list with 1:1 allocation. All patients received cholecystectomy 2–3 months after drainage. The primary endpoint was abdominal pain score, and the intention-to-treat population was analyzed. (ClinicalTrials.gov: NCT03701464). Findings: Between Oct 1, 2018 and Feb 29, 2020, 22 out of 61 consecutive AC patients were enrolled in the final analysis. The mean abdominal pain scores before drainage, and at 24, 48, and 72 h after drainage in ENGBD were 6.9 ± 1.1, 4.3 ± 1.2, 2.2 ± 0.8 and 1.5 ± 0.5, respectively, while those of PTGBD were 7.4 ± 1.2, 6.2 ± 1.2, 5.3 ± 1.0 and 3.7 ± 0.9; and the mean gallbladder area tenderness scores were 8.4 ± 1.2, 5.7 ± 0.9, 3.5 ± 0.7, 2.5 ± 0.5 for ENGBD and 8.6 ± 0.9, 7.3 ± 1.0, 7.4 ± 0.5, 4.8 ± 0.9 for PTGBD. The mean abdominal pain and gallbladder area tenderness scores of the ENGBD significantly decreased than the PTGBD (group × time interaction P

Background Supportive treatment is an important and effective part of the management for patients with life-threatening diseases. This study aims to identify and evaluate the forms of supportive care for patients with respiratory diseases. Methods An umbrella review of supportive care for patient with respiratory diseases was undertaken. We comprehensively searched the following databases: Medline, EMBASE, Web of Science, CNKI (China National Knowledge Infrastructure), Wanfang Data and CBM (SinoMed) from their inception to 31 March 2020, and other sources to identify systematic reviews and meta-analyses related to supportive treatments for patient with respiratory diseases including Coronavirus Disease 2019 (COVID-19), severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and influenza. We assessed the methodological quality using the AMSTAR score and the quality of the evidence for the primary outcomes of each included systematic review and meta-analysis. Results We included 18 systematic reviews and meta-analyses in this study. Most studies focused on the respiratory and circulatory support. Ten studies were of high methodological quality, five studies of medium quality, and three studies of low quality. According to four studies extracorporeal membrane oxygenation did not reduce mortality in adults [odds ratio/relative risk (OR/RR) ranging from 0.71 to 1.28], but two studies reported significantly lower mortality in patients receiving venovenous extracorporeal membrane oxygenation than in the control group (OR/RR ranging from 0.38 to 0.73). Besides, monitoring of vital signs and increasing the number of medical staff may also reduce the mortality in patients with respiratory diseases. Conclusions Our overview suggests that supportive care may reduce the mortality of patients with respiratory diseases to some extent. However, the quality of evidence for the primary outcomes in the included studies was low to moderate. Further systematic reviews and meta-analyses are needed to address the evidence gap regarding the supportive care for SARS, MERS and COVID-19.

This project aims to evaluate the methods and reporting quality of practice guidelines of five different viruses that have caused Public Health Emergencies of International Concern (PHEIC) over 20 past years: the severe acute respiratory syndrome coronavirus (SARS-CoV), Ebola virus, Middle East respiratory syndrome coronavirus (MERS-CoV), Zika virus and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We systematically searched databases, guideline websites and government health agency websites from their inception to February 02, 2020 to extract practice guidelines for SARS-CoV, Ebola virus, MERS-CoV, Zika virus, SARS-CoV-2 and the diseases they caused. The literature was screened independently by four researchers. Then, fifteen researchers evaluated the quality of included guidelines using the AGREE-II (Appraisal of Guidelines for Research and Evaluation II, for methodological quality) instrument and RIGHT (Reporting Items for practice Guidelines in Healthcare, for reporting quality) statement. Finally, a total of 81 guidelines were included, including 21 SARS-CoV guidelines, 11 Ebola virus (EBOV) guidelines, 9 MERS-CoV guidelines, 10 Zika Virus guidelines and 30 SARS-CoV-2 guidelines. The evaluation of the methodological quality indicated that the mean scores of each domain for guidelines of each virus were all below 60%, the scores for guidelines in the domains of "clarity of presentation" being the highest and in the "editorial independence" lowest. The mean reporting rate of each domain for guidelines of each virus was also less than 60%: the reporting rates for the domain "background" were highest, and for the domain "funding and interests" lowest. The methodological and reporting quality of the practice guidelines for SARS-CoV, Ebola virus, MERS-CoV, Zika virus and SARS-CoV-2 guidelines tend to be low. We recommend to follow evidence-based methodology and the RIGHT statement on reporting when developing guidelines.

BackgroundSupportive treatment is an important and effective part of the management for patients with life-threatening diseases. This study aims to identify and evaluate the forms of supportive care for patients with respiratory diseases.MethodsAn umbrella review of supportive care for patient respiratory diseases was undertaken. We comprehensively searched the following databases: Medline, EMBASE, Web of Science, CNKI (China National Knowledge Infrastructure), Wanfang Data and CBM (SinoMed) from their inception to 31 March 2020, and other sources to identify systematic reviews and meta-analyses related to supportive treatments for patient with respiratory diseases including COVID-19, SARS, MERS and influenza. We assessed the methodological quality using the AMSTAR score and the quality of the evidence for the primary outcomes of each included systematic review and meta-analysis.ResultsWe included 18 systematic reviews and meta-analyses in this study. Most studies focused on the respiratory and circulatory support. Ten studies were of high methodological quality, five studies of medium quality, and three studies of low quality. According to four studies extracorporeal membrane oxygenation did not reduce mortality in adults (OR/RR ranging from 0.71 to 1.28), but two studies reported significantly lower mortality in patients receiving venovenous extracorporeal membrane oxygenation than in the control group (OR/RR ranging from 0.38 to 0.73). Besides, monitoring of vital signs and increasing the number of medical staff may also reduce the mortality in patients with respiratory diseases.ConclusionsOur overview suggests that supportive care may reduce the mortality of patients with respiratory diseases to some extent. However, the quality of evidence for the primary outcomes in the included studies was low to moderate. Further systematic reviews and meta-analyses are needed to address the evidence gap regarding the supportive care for SARS, MERS and COVID-19.

BackgroundCOVID-19, a disease caused by SARS-CoV-2 coronavirus, has now spread to most countries and regions of the world. As patients potentially infected by SARS-CoV-2 need to visit hospitals, the incidence of nosocomial infection can be expected to be high. Therefore, a comprehensive and objective understanding of nosocomial infection is needed to guide the prevention and control of the epidemic.MethodsWe searched major international and Chinese databases Medicine, Web of science, Embase, Cochrane, CBM(China Biology Medicine disc), CNKI (China National Knowledge Infrastructure) and Wanfang database)) for case series or case reports on nosocomial infections of COVID-19, SARS(Severe Acute Respiratory Syndromes) and MERS(Middle East Respiratory Syndrome) from their inception to March 31st, 2020. We conducted a meta-analysis of the proportion of nosocomial infection patients in the diagnosed patients, occupational distribution of nosocomial infection medical staff and other indicators.ResultsWe included 40 studies. Among the confirmed patients, the proportions of nosocomial infections were 44.0%, 36.0% and 56.0% for COVID-19, SARS and MERS, respectively. Of the confirmed patients, the medical staff and other hospital-acquired infections accounted for 33.0% and 2.0% of COVID-19 cases, 37.0% and 24.0% of SARS cases, and 19.0% and 36.0% of MERS cases, respectively. Nurses and doctors were the most affected among the infected medical staff. The mean numbers of secondary cases caused by one index patient were 29.3 and 6.3 for SARS and MERS, respectively.ConclusionsThe proportion of nosocomial infection in patients with COVID-19 was 44%. Patients attending hospitals should take personal protection. Medical staff should be awareness of the disease to protect themselves and the patients.

BackgroundThe outbreak of the coronavirus disease 2019 (COVID-19) has had a massive impact on the whole world. Computed tomography (CT) has been widely used in the diagnosis of this novel pneumonia. This study aims to understand the role of CT for the diagnosis and the main imaging manifestations of patients with COVID-19.MethodsWe conducted a rapid review and meta-analysis on studies about the use of chest CT for the diagnosis of COVID-19. We comprehensively searched databases and preprint servers on chest CT for patients with COVID-19 between 1 January 2020 and 31 March 2020. The primary outcome was the sensitivity of chest CT imaging. We also conducted subgroup analyses and evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.ResultsA total of 104 studies with 5694 patients were included. Using RT-PCR results as reference, a meta-analysis based on 64 studies estimated the sensitivity of chest CT imaging in COVID-19 was 99% (95% CI, 0.97-1.00). If case reports were excluded, the sensitivity in case series was 96% (95% CI, 0.93-0.99). The sensitivity of CT scan in confirmed patients under 18 years old was only 66% (95% CI, 0.11-1.00). The most common imaging manifestation was ground-glass opacities (GGO) which was found in 75% (95% CI, 0.68-0.82) of the patients. The pooled probability of bilateral involvement was 84% (95% CI, 0.81-0.88). The most commonly involved lobes were the right lower lobe (84%, 95% CI, 0.78-0.90) and left lower lobe (81%, 95% CI, 0.74-0.87). The quality of evidence was low across all outcomes.ConclusionsIn conclusion, this meta-analysis indicated that chest CT scan had a high sensitivity in diagnosis of patients with COVID-19. Therefore, CT can potentially be used to assist in the diagnosis of COVID-19.

Background In December 2019, a pneumonia caused by a novel coronavirus (SARS-CoV-2) emerged in Wuhan, China and has rapidly spread around the world since then. Aim This study aims to understand the research gaps related to COVID-19 and propose recommendations for future research. Methods We undertook a scoping review of COVID-19, comprehensively searching databases and other sources to identify literature on COVID-19 between 1 December 2019 and 6 February 2020. We analysed the sources, publication date, type and topic of the retrieved articles/studies. Results We included 249 articles in this scoping review. More than half (59.0%) were conducted in China. Guidance/guidelines and consensuses statements (n = 56; 22.5%) were the most common. Most (n = 192; 77.1%) articles were published in peer-reviewed journals, 35 (14.1%) on preprint servers and 22 (8.8%) posted online. Ten genetic studies (4.0%) focused on the origin of SARS-CoV-2 while the topics of molecular studies varied. Nine of 22 epidemiological studies focused on estimating the basic reproduction number of COVID-19 infection (R0). Of all identified guidance/guidelines (n = 35), only ten fulfilled the strict principles of evidence-based practice. The number of articles published per day increased rapidly until the end of January. Conclusion The number of articles on COVID-19 steadily increased before 6 February 2020. However, they lack diversity and are almost non-existent in some study fields, such as clinical research. The findings suggest that evidence for the development of clinical practice guidelines and public health policies will be improved when more results from clinical research becomes available.

ObjectiveThis study applied the public genetic databases high-throughput gene expression omnibus (GEO) database to compare the difference of gene screening between the repeated implantation failure (RIF) patients and women with normal endometrium. This study aims to provide additional information for the diagnosis and treatment in RIF patients through the gene set enrichment analysis and the construction of protein–protein interactions (PPIs) network.MethodThe human endometrial microarray data of RIF and normal control group were obtained from the GEO database provided by the National Center for Biotechnology Information (NCBI). The analysis and the review of differential gene screening, gene ontology (GO) pathway analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and PPIs network construction were carried out.Result273 genes with differential expression, 87 up-regulated and 186 down-regulated genes, were obtained through differential gene analysis. 50 genes with the most significant differential expression fold change were screened for subsequent analysis. KEGG results indicated that the top three related pathways were cancer pathway, MAPK signaling pathway, and homologous recombination pathway when the relevant pathways were sequenced according to the correlation size. GO analysis showed that differentially expressed genes were involved in protein phosphorylation, complement activation, and other biological processes. PPIs analysis demonstrated that targeted genes show high correlation to the endometrial receptivity, including PAEP, CXCL14, HOXB3, CD55, and VEGFA, all were down-regulated in RIF endometrial tissues compared to the control group, and these genes also influenced and regulated each other.ConclusionThrough public databases and bioinformatics, several factors in endometrial receptivity that affect RIF directly and indirectly were found. In particular, the immune and angiogenesis factors stood out the most. The different genes which regulate the immune response and angiogenesis response may become new targeted treatment for RIF.

Background: Gallbladder drainage plays a key role in the management of high-risk patients with acute cholecystitis. Percutaneous transhepatic gallbladder drainage (PTGBD) is a common drainage method, and endoscopic naso-gallbladder drainage (ENGBD) is an alternative natural orifice transluminal endoscopic procedure. No study has clearly declared the better method or their impact on subsequent cholecystectomy. Methods: We performed an open-label, prospective randomized controlled parallel trial at a tertiary surgical center. Patients who needed gallbladder decompression were randomly assigned to receive ENGBD or PTGBD. The primary endpoint was the abdominal pain score, and the intention-to-treat population was analyzed. Findings: Twenty-two participants were enrolled, and the abdominal pain scores of the ENGBD group before drainage and 24, 48, and 72 hours after drainage were 6.0 (6.0-8.0), 4.0 (3.0-6.0), 2.0 (2.0-2.0) and 1.0 (1.0-2.0), respectively, while those of the PTGBD group were 7.0 (6.0-9.0), 6.0 (6.0-7.0), 5.0 (4.0-6.0) and 3.0 (3.0-5.0), respectively. The abdominal pain scores were significantly lower in the ENGBD group, as were the gallbladder area tenderness score(P

Orthogonal frequency division multiplexing/offset quadrature amplitude modulation (OFDM/OQAM) is a promising modulation candidate for passive optical network (PON) due to its high flexibility, better time–frequency focusing characteristic, great resistance to the inter symbol and inter carrier interferences and higher spectrum efficiency compared to OFDM. However, the intrinsic imaginary interference together with linear and nonlinear distortions make it more difficult to recover the transmitted OFDM/OQAM signal at the receiver side. To mitigate the transmission impairments, a modified convolutional neural network (CNN) is utilized to learn the channel state information and the constellation demapping mechanism for OFDM/OQAM-PON. The distorted received signals are equalized implicitly to obtain the transmitted binary bits directly. The simulation results show that the CNN based receiver (Rx) can compensate the linear and nonlinear distortions more effectively compared to traditional pilot-based Rx, especially for the high order modulation long-reach PON.

Background Several systematic reviews and meta-analyses have assessed the association between egg consumption and human health, but the evidence is often conflicting. Methods We conducted a systematic literature search to find all systematic reviews and meta-analyses that assess the association between egg consumption and any type of health outcome. We used AMSTAR to evaluate the methodological quality of the reviews, and GRADE to determine the quality of evidence. We visualized the results using a human anatomy diagram and evidence mapping. Results Our search revealed 29 systematic reviews and meta-analyses. Eight studies were of high methodological quality, 16 studies of medium quality, and five studies of low quality. We identified 34 primary outcomes from the included 29 reviews, which were combined into a total of 22 different health outcomes. Two of the primary outcomes were based on high-quality evidence, 18 on moderate-quality evidence, and 14 on low-quality evidence. Egg consumption was associated with an increased risk of two diseases and decreased risk of six outcomes. For ten outcomes, no significant association was found, and for four outcomes, different reviews came to conflicting conclusions. Conclusions The association between egg consumption and the risk of cancer, diabetes, cardiovascular diseases and other related diseases has been studied in several meta-analyses. The evidence from different studies on the same topic was often conflicting, which can complicate the making of dietary recommendations.

Background COVID-19, a disease caused by SARS-CoV-2 coronavirus, has now spread to most countries and regions of the world. As patients potentially infected by SARS-CoV-2 need to visit hospitals, the incidence of nosocomial infection can be expected to be high. Therefore, a comprehensive and objective understanding of nosocomial infection is needed to guide the prevention and control of the epidemic. Methods We searched major international and Chinese databases: Medicine, Web of Science, Embase, Cochrane, CBM (China Biology Medicine disc), CNKI (China National Knowledge Infrastructure) and Wanfang database for case series or case reports on nosocomial infections of COVID-19, SARS (severe acute respiratory syndromes) and MERS (Middle East respiratory syndrome) from their inception to March 31st, 2020. We conducted a meta-analysis of the proportion of nosocomial infection patients in the diagnosed patients, occupational distribution of nosocomial infection medical staff. Results We included 40 studies. Among the confirmed patients, the proportions of nosocomial infections with early outbreaks of COVID-19, SARS, and MERS were 44.0%, 36.0%, and 56.0%, respectively. Of the confirmed patients, the medical staff and other hospital-acquired infections accounted for 33.0% and 2.0% of COVID-19 cases, 37.0% and 24.0% of SARS cases, and 19.0% and 36.0% of MERS cases, respectively. Nurses and doctors were the most affected among the infected medical staff. The mean numbers of secondary cases caused by one index patient were 29.3 and 6.3 for SARS and MERS, respectively. Conclusions The proportion of nosocomial infection in patients with COVID-19 was 44% in the early outbreak. Patients attending hospitals should take personal protection. Medical staff should be awareness of the disease to protect themselves and the patients.

We aimed to establish the quantitative structure–property relationship (QSPR) with thermal stabilities of 90 structurally diverse second-order nonlinear optical (NLO) chromophore molecules using easily understood and obtained physicochemical molecular descriptors. These descriptors include number of C atoms (NC), number of F atoms (NF), relative number of N atoms (RNN) and relative number of triple bonds (RNTB). Multiple linear regression (MLR) and support vector machine (SVM) were used to develop the linear and nonlinear models, respectively. The obtained linear model had a square of correlation coefficient R 2 = 0.928 with a root mean square error (RMS) error of 19.28 for the training set, while R 2 = 0.828, RMS = 29.79 for the test set. The RMS error in prediction for overall data set is 21.65. The nonlinear model gave better results: for the training set R 2 = 0.949, RMS = 16.16, and for the test set R 2 = 0.867, RMS = 25.40. The RMS error in prediction for overall data set is 18.38. The proposed mode...