The role of viruses in human acute appendicitis: a systematic literature review.

BACKGROUND: There have been debates about the human appendix function, and while previous research suggested it might be a vestigial organ with no functional significance, recent studies have pointed out that it might have an important role in the immune system. Acute appendicitis (AA) is a common cause of emergency abdominal surgery in the world. Some epidemiologic investigations have found an association between appendicitis and viral infections. In this study, we have reviewed systematically articles to discover viral infections that cause appendicitis and find any possible correlations between the two. METHODS: This systematic review was performed by searching among electronic databases including Web of Science, PubMed, Scopus, and EMBASE on viruses and appendicitis topics. RESULTS: Conducted search leads to 983 results in all databases after the duplicate removal and screening by title, abstract, and full-text based on inclusion criteria lead to 19 studies. There were several assays to detect the viruses, which are thought to be AA causative agents. RT-PCR and immunoassays were the mainstay methods to detect the probable cause. CONCLUSION: Investigations suggested that some viruses including measles virus (MV), influenza virus, dengue fever virus (DFV), human immunodeficiency virus (HIV), human herpesviruses, rotavirus, and adenovirus are associated with acute appendicitis. Despite the available reports, the specific mechanisms behind the relationship between acute appendicitis and viral infections are yet to be understood. Therefore, further investigations are necessary to find out the pathogenesis and pathophysiology of viral complications in appendicitis.

Effect of herbal compounds on coronavirus; a systematic review and meta-analysis.

BACKGROUND: The new coronavirus (COVID-19) has been transmitted exponentially. Numerous studies have been performed in recent years that have shown the inhibitory effect of plant extracts or plant-derived compounds on the coronavirus family. In this study, we want to use systematic review and meta-analysis to answer the question, which herbal compound has been more effective? MAIN BODY: The present study is based on the guidelines for conducting meta-analyzes. An extensive search was conducted in the electronic database, and based on the inclusion and exclusion criteria, articles were selected and data screening was done. Quality control of articles was performed. Data analysis was carried out in STATA software. CONCLUSION: Due to the variety of study methods, definitive conclusions are not possible. However, in this study, we attempted to gather all the available evidence on the effect of plant compounds on SARS-COV-2 to be used for the development and use of promising antiviral agents against this virus and other coronaviruses. Trypthantrin, Sambucus extract, S. cusia extract, Boceprevir and Indigole B, dioica agglutinin urtica had a good effect on reducing the virus titer. Also among the compounds that had the greatest effect on virus inhibition, Saikosaponins B2, SaikosaponinsD, SaikosaponinsA and Phillyrin, had an acceptable selectivity index greater than 10. Andrographolide showed the highest selectivity index on SARS-COV-2. Our study confirmed insufficient data to support alkaloid compounds against SARS-COV-2, and the small number of studies that used alkaloid compounds was a limitation. It is recommended to investigate the effect of more alkaloid compounds against Corona virus.

Salivirus infection: Systematic review and meta-analysis of association with gastrointestinal symptoms in children.

Salivirus (SaV) is a newly described member of the family Picornaviridae that has been associated with gastrointestinal (GI) symptoms, particularly in children. The aim of the present study was to evaluate the prevalence of SaV in symptomatic children and its potential association with GI complications. A systematic search was conducted from 01 December 2009 to 10 December 2020, in three major English databases, including Scopus, PubMed and Web of Science as well as Google scholar search engine. Random effect model-based overall prevalence and odds ratio (OR) were assessed in cross-sectional and case-control studies by STATA 14.1. The random effect model-based pooled prevalence of SaV was 1.6% (95% CI, 0.010-0.022%) and overall OR for all eight case-control studies indicated an association (3.19 with 95% confidence interval 1.35-7.57) that was not statistically significant, due to the small number of studies available. More comprehensive case-control studies in multiple geographies should be conducted on the prevalence of SaV in children.

Worldwide prevalence of microbial agents' coinfection among COVID-19 patients: A comprehensive updated systematic review and meta-analysis.

BACKGROUND: To provide information about pathogens' coinfection prevalence with SARS-CoV-2 could be a real help to save patients' lives. This study aims to evaluate the pathogens' coinfection prevalence among COVID-19 patients. METHOD: In order to find all of the relevant articles, we used systematic search approach. Research-based databases including PubMed, Web of Science, Embase, and Scopus, without language restrictions, were searched to identify the relevant bacterial, fungal, and viral coinfections among COVID-19 cases from December 1, 2019, to August 23, 2021. In order to dig deeper, other scientific repositories such as Medrxiv were probed. RESULTS: A total of 13,023 studies were found through systematic search. After thorough analysis, only 64 studies with 61,547 patients were included in the study. The most common causative agents of coinfection among COVID-19 patients were bacteria (pooled prevalence: 20.97%; 95% CI: 15.95-26.46; I2 : 99.9%) and less frequent were virus coinfections (pooled prevalence: 12.58%; 95% CI: 7.31-18.96; I2 : 98.7%). The pooled prevalence of fungal coinfections was also 12.60% (95% CI: 7.84-17.36; I2 : 98.3%). Meta-regression analysis showed that the age sample size and WHO geographic region did not influenced heterogeneity. CONCLUSION: We identified a high prevalence of pathogenic microorganism coinfection among COVID-19 patients. Because of this rate of coinfection empirical use of antibacterial, antifungal, and antiviral treatment are advisable specifically at the early stage of COVID-19 infection. We also suggest running simultaneously diagnostic tests to identify other microbiological agents' coinfection with SARS-CoV-2.

An overview on the seven pathogenic human coronaviruses.

To date, seven human coronaviruses (HCoVs) have been detected: HCoV-NL63, HCoV-229E, HCoV-HKU1, HCoV-OC43, severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2. Four of these viruses, including HCoV-NL63, -229E, -HKU1 and -OC43, usually cause mild-to-moderate respiratory diseases with a seasonal pattern. Since 2000, three new HCoVs have emerged with a significant mortality rate. Although SARS-CoV and MERS-CoV caused an epidemic in some countries, SARS-CoV-2 escalated into a pandemic. All HCoVs can cause severe complications in the elderly and immunocompromised individuals. The bat origin of HCoVs, the presence of intermediate hosts and the nature of their viral replication suggest that other new coronaviruses may emerge in the future. Despite the fact that all HCoVs share similarities in viral replication, they differ in their accessory proteins, incubation period and pathogenicity. This study aims to review these differences between the seven HCoVs.

Long noncoding RNAs in respiratory viruses: A review.

Long noncoding RNAs (lncRNAs) are defined as RNA molecules longer than 200 nucleotides that can regulate gene expression at the transcriptional or post-transcriptional levels. Both human lncRNAs and lncRNAs encoded by viruses can modulate the expression of host genes which are critical for viral replication, latency, activation of signalling pathways, cytokine and chemokine production, RNAi processing, expression of interferons (IFNs) and interferon-stimulated genes (ISGs). Studies on lncRNAs as key regulators of host-virus interactions may give new insights into therapeutic strategies for the treatment of related diseases. This current review focuses on the role of lncRNAs, and their interactions with respiratory viruses including influenza A virus (IAV), respiratory syncytial virus (RSV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

The Role of Bacterial and Fungal Human Respiratory Microbiota in COVID-19 Patients.

Recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), has led to a worldwide pandemic with millions of infected patients. Alteration in humans' microbiota was also reported in COVID-19 patients. The alteration in human microbiota may contribute to bacterial or viral infections and affect the immune system. Moreover, human's microbiota can be altered due to SARS-CoV-2 infection, and these microbiota changes can indicate the progression of COVID-19. While current studies focus on the gut microbiota, it seems necessary to pay attention to the lung microbiota in COVID-19. This study is aimed at reviewing respiratory microbiota dysbiosis among COVID-19 patients to encourage further studies on the field for assessment of SARS-CoV-2 and respiratory microbiota interaction.