Search results for "ARS"

To B or Not to B: Comparative Genomics Suggests Arsenophonus as a Source of B Vitamins in Whiteflies

2018

Insect lineages feeding on nutritionally restricted diets such as phloem sap, xylem sap, or blood, were able to diversify by acquiring bacterial species that complement lacking nutrients. These bacteria, considered obligate/primary endosymbionts, share a long evolutionary history with their hosts. In some cases, however, these endosymbionts are not able to fulfill all of their host's nutritional requirements, driving the acquisition of additional symbiotic species. Phloem-feeding members of the insect family Aleyrodidae (whiteflies) established an obligate relationship with Candidatus Portiera aleyrodidarum, which provides its hots with essential amino acids and carotenoids. In addition, ma…

Early detection of SARS-CoV-2 infection cases or outbreaks at nursing homes by targeted wastewater tracking

2021

Objectives Near-source tracking of SARS-CoV-2 RNA in the sewage drains serving particular buildings may allow rapid identification of SARS-CoV-2 infection cases or local outbreaks. In this pilot study, we investigated whether this was the case for nursing homes (NH). Methods The study involved five NH (from A to E) affiliated to the Clínico-Malvarrosa Health Department, Valencia (Spain). These were nursing or mixed nursing/care homes of different sizes, altogether providing care for 472 residents attended by a staff of 309. Near-source sewage samples were screened for presence of SARS-CoV-2 RNA by RT-qPCR at least 5 days per week during the study period. SARS-CoV-2 RNA testing in nasopharyn…

Point-of-care evaluation of a rapid antigen test (CLINITESTⓇ Rapid COVID-19 Antigen Test) for diagnosis of SARS-CoV-2 infection in symptomatic and as…

2021

AbstractRapid antigen assays (RAD) based on lateral flow immunochromatography (LFIC) technology have emerged as a valuable tool for the control of COVID-19 pandemic. Manufacturer□independent, real□world evaluation of these assays is crucial given the considerable heterogeneity reported in their clinical and analytical performances. Here, we report for the first time on the point-of-care performance of the CLINITEST® Rapid COVID-19 Antigen Test (Siemens, Healthineers, Erlangen, Germany) to detect SARS-CoV-2 infection in presumptive COVID-19 cases or asymptomatic close contacts of COVID-19 patients. When compared to RT-PCR, the overall sensitivity of the assay was 80.2 (95% CI, 70.9-87.1) for…

Therapeutic strategies for severe COVID-19: a position paper from the Italian Society of Infectious and Tropical Diseases (SIMIT)

2021

Abstract Scope Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has become pandemic, reaching almost one million death worldwide. At present standard treatment for coronavirus disease 2019 (COVID-19) is not well defined because the evidence, either from randomized or observational studies, with conflicting results, has led to rapid changes in treatment guidelines. Our aim was to narratively summarize the available literature on the management of COVID-19 in order to combine current evidence and interpretation of the data by experts who are treating patients in the frontline setting. Methods The panel conducted a detailed review of the literature and eventual press rele…

An umbrella review of systematic reviews with meta-analyses evaluating positive and negative outcomes of Hydroxychloroquine and chloroquine therapy

2021

Background & aims: Hydroxychloroquine (HCQ) and chloroquine (CQ) are anti-malarial drugs frequently used in the rheumatologic field. They were recently identified as potential therapeutic options for Coronavirus Disease (COVID-19). The present study aims to map and grade the diverse health outcomes associated with HCQ/CQ using an umbrella review approach. Methods: Umbrella review of systematic reviews of observational and intervention studies. For observational studies, random-effects summary effect size, 95% confidence interval, and 95% prediction interval were estimated. We also assessed heterogeneity, evidence for small-study effect, and evidence for excess significance bias. The quality…

Three-dimensional analysis of the physiological foramen geometry of maxillary and mandibular molars by means of micro-CT.

2017

The aim of this study was to investigate the physiological foramen diameter, shape and distance between physiological and anatomical apex of maxillary and mandibular first and second molars. Accurate knowledge of the physiological foramina morphology; thus, inherent mechanical shaping technical hindrances, is decisive when taking the corresponding root canal final preparation decision. The morphological dimensions of a total of 1727 physiological foramina were investigated by means of micro-computed tomography. Mean narrow and wide (to a high number, oval) diameters of the physiological foramen were 0.24, 0.22 and 0.33 mm and 0.33, 0.31 and 0.42 mm in mesiobuccal (MB), distobuccal (DB) and …

The dimer-monomer equilibrium of SARS-CoV-2 main protease is affected by small molecule inhibitors

2021

AbstractThe maturation of coronavirus SARS-CoV-2, which is the etiological agent at the origin of the COVID-19 pandemic, requires a main protease Mpro to cleave the virus-encoded polyproteins. Despite a wealth of experimental information already available, there is wide disagreement about the Mpro monomer-dimer equilibrium dissociation constant. Since the functional unit of Mpro is a homodimer, the detailed knowledge of the thermodynamics of this equilibrium is a key piece of information for possible therapeutic intervention, with small molecules interfering with dimerization being potential broad-spectrum antiviral drug leads. In the present study, we exploit Small Angle X-ray Scattering (…

Human molecular chaperones share with SARS-CoV-2 antigenic epitopes potentially capable of eliciting autoimmunity against endothelial cells: possible…

2020

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), the cause of COVID-19 disease, has the potential to elicit autoimmunity because mimicry of human molecular chaperones by viral proteins. We compared viral proteins with human molecular chaperones, many of which are heat shock proteins, to determine if they share amino acid-sequence segments with immunogenic-antigenic potential, which can elicit cross-reactive antibodies and effector immune cells with the capacity to damage-destroy human cells by a mechanism of autoimmunity. We identified the chaperones that can putatively participate in molecular mimicry phenomena after SARS-CoV-2 infection, focusing on those for which endotheli…

2016

AbstractDespite the high global prevalence of dry eye syndrome (DES), the fundamental processes underlying this pathology remain largely unexplored. Therefore, this study endeavoured to investigate in-depth the tear proteome of DES patients employing the mass spectrometry (MS)-based proteomic strategies. Eighty patients were recruited and subdivided into three major DES subgroups, which are the aqueous-deficient (DRYaq), evaporative (DRYlip) and a combination of the two (DRYaqlip), as well as healthy subjects (CTRL). Discovery proteomics strategy was employed to identify large number of significantly differentially expressed tear proteins in DRYlip vs. CTRL, DRYaq vs. CTRL and DRYaqlip vs. …

Arsenic promotes NF-Κb-mediated fibroblast dysfunction and matrix remodeling to impair muscle stem cell function

2016

Abstract Arsenic is a global health hazard that impacts over 140 million individuals worldwide. Epidemiological studies reveal prominent muscle dysfunction and mobility declines following arsenic exposure; yet, mechanisms underlying such declines are unknown. The objective of this study was to test the novel hypothesis that arsenic drives a maladaptive fibroblast phenotype to promote pathogenic myomatrix remodeling and compromise the muscle stem (satellite) cell (MuSC) niche. Mice were exposed to environmentally relevant levels of arsenic in drinking water before receiving a local muscle injury. Arsenic-exposed muscles displayed pathogenic matrix remodeling, defective myofiber regeneration …