Biology subjects

Rivas, F.

Publications and source records attributed to Rivas, F..

5 recordsLinked to original sources

bioRxiv2024

Rthoptera: standardized insect bioacoustics in R

O_LICrickets were the first study subjects at the dawn of bioacoustics, yet, almost 100 years later, freely available and robust analysis tools and protocols are still needed. C_LIO_LIWe introduce Rthoptera, a new open-source R package for the analysis of insect acoustic signals, offering accurate graphics and standardised temporal and spectral measurements through a streamlined workflow. Our package delivers results in a fraction of the time typically required by multi-software methods. Most of the functions have interactive versions (Shiny applications), facilitating their adoption by researchers with any level of technical expertise. C_LIO_LINew acoustic metrics are introduced: Spectral Excursion, Pattern Complexity Index, Temporal Excursion, Dynamic Excursion, and Broadband Activity Index. C_LIO_LIAccompanied by an appropriate recording protocol, our tool can become the backbone of a standard analysis protocol for comparative insect bioacoustics. C_LI

bioinformatics↗

bioRxiv2023

Unveiling Vaginal Fibrosis: A Novel Murine Model Using Bleomycin and Epithelial Disruption

ObjectiveDevelop, validate, and characterize a fibrotic murine vaginal wound healing model using bleomycin instillations and epithelial disruption. ApproachWe tested the effect of repeated bleomycin instillations with mucosal layer disruption on induction of vaginal fibrosis. Tissue samples collected at various time points were analyzed for fibrosis-related gene expression changes and collagen content. ResultsLow (1.5U/kg) and high-dose (2.5U/kg) bleomycin instillations alone did not induce fibrosis, but when high-dose bleomycin was combined with epithelial disruption, increased pro-fibrotic gene expression and trichrome staining were observed. To evaluate spatial and temporal changes in the ECM structure and gene expression, tissue samples were collected at 1 day, 3 weeks, and 6 weeks after bleomycin and epithelial disruption. Data analyses revealed a significant decrease in matrix metabolizing genes and an increase in pro-fibrotic genes and inhibitors of matrix metabolizing genes in the bleomycin plus epithelial disruption group at 3 weeks. Elevated levels of the profibrotic genes Acta2, Col1a1, and Col3a were exclusively detected in this group at 3 weeks, and trichrome staining confirmed increased collagen content after 3 weeks. Hydroxyproline levels showed a tendency towards elevation at 3 weeks (p=0.12) and 6 weeks (p=0.14), indicating fibrosis manifestation at 3 weeks and resolution by 6 weeks post-instillation and epithelial disruption. InnovationWe combined bleomycin instillations with epithelial disruption to induce fibrosis and understand the mechanisms of the vaginal repair process. ConclusionsEpithelial disruption combined with bleomycin induces murine vaginal fibrosis within three weeks, characterized by increased collagen synthesis. Remarkably, the vaginal tissue fully recovers within six weeks, elucidating the regenerative capacity of the vagina.

physiology↗

bioRxiv2023

Identification of culturable fungi and bacteria in mosquito saliva and impact on arbovirus infection in vitro

Mosquito saliva plays a key role in arbovirus transmission and pathogenesis. This study isolated and identified culturable fungal and bacterial colonies from saliva harvested from Aedes aegypti (lab strain) and Culex pipiens (field-collected) mosquitoes. For the first time, Penicillium crustosum was identified in mosquito saliva. Culturable bacteria detected in mosquito saliva included Serratia marcescens, Serratia nematodiphila, Enterobacter spp., and Klebsiella spp., which were previously identified as mosquito or insect endosymbionts in the midgut or other organs. Analysis with 16S metagenomics showed that the bacterial community in saliva appeared more diverse than the bacterial communities in midguts. Blood feeding did not affect the fungal or bacterial load in mosquito saliva. Oral treatment of adult mosquitoes with antibiotics or an antifungal drug resulted in a significant reduction of resp. bacteria or fungi present in the mosquito saliva. Co-incubation of Semliki Forest virus with saliva from antibiotic or antifungal treated mosquitoes triggered a decrease in viral infection in human skin fibroblasts compared to non-treated saliva. This work lays the foundation for further exploration of the impact of fungi and bacteria in mosquito saliva on both vector competence and arbovirus infection in the mammalian host.

microbiology↗

bioRxiv2022

Injury and a program of fetal wound healing in the fetal and neonatal extrahepatic bile duct

IntroductionBiliary atresia (BA) is an obstructive cholangiopathy that initially affects the extrahepatic bile ducts (EHBDs) of neonates. The etiology is uncertain, but evidence points to a prenatal cause; however, the response of the fetal EHBD to injury remains unknown. The objective of this study was to define the fetal response to EHBD injury and to determine whether it follows a fetal wound healing paradigm. MethodsMouse, rat, sheep, and human EHBD samples were studied at different developmental time points. Models included a fetal sheep model of prenatal hypoxia, human BA EHBD remnants and liver samples taken at the time of the Kasai procedure, EHBDs isolated from neonatal rats and mice, and spheroids and other models generated from primary neonatal mouse cholangiocytes. ResultsA wide layer of high molecular weight HA encircling the lumen was characteristic of the normal perinatal but not adult EHBD. This layer, which was surrounded by collagen, expanded in injured ducts in parallel with extensive peribiliary gland (PBG) hyperplasia, increased mucus production and elevated serum bilirubin levels. BA EHBD remnants similarly showed increased HA centered around ductular structures compared with age-appropriate controls. High molecular weight HA typical of the fetal/neonatal ducts caused increased cholangiocyte spheroid growth, whereas low molecular weight HA induced abnormal epithelial morphology; low molecular weight HA caused matrix swelling in a bile duct-on-a-chip device. ConclusionThe fetal/neonatal EHBD, including in human EHBD remnants from Kasai surgeries, demonstrated an injury response with high levels of HA typical of the regenerative, scarless program termed fetal wound healing. Although generally beneficial, the expanded peri-luminal HA layer may swell and lead to elevated bilirubin levels and obstruction of the EHBD.

physiology↗

bioRxiv2018

Bipolar multiplex families have an increased burden of common risk variants for psychiatric disorders

Multiplex families with a high prevalence of a psychiatric disorder are often examined to identify rare genetic variants with large effect sizes. In the present study, we analysed whether the risk for bipolar disorder (BD) in BD multiplex families is influenced by common genetic variants. Furthermore, we investigated whether this risk is conferred mainly by BD-specific risk variants or by variants also associated with the susceptibility to schizophrenia or major depression. In total, 395 individuals from 33 Andalusian BD multiplex families as well as 438 subjects from an independent, sporadic BD case-control cohort were analysed. Polygenic risk scores (PRS) for BD, schizophrenia, and major depression were calculated and compared between the cohorts. Both the familial BD cases and unaffected family members had significantly higher PRS for all three psychiatric disorders than the independent controls, suggesting a high baseline risk for several psychiatric disorders in the families. Moreover, familial BD cases showed significantly higher BD PRS than unaffected family members and sporadic BD cases. A plausible hypothesis is that, in multiplex families with a general increase in risk for psychiatric disease, BD development is attributable to a high burden of common variants that confer a specific risk for BD. The present analyses, therefore, demonstrated that common genetic risk variants for psychiatric disorders are likely to contribute to the high incidence of affective psychiatric disorders in the multiplex families. The PRS explained only part of the observed phenotypic variance and rare variants might have also contributed to disease development.

genetics↗