Reproductive biology of Oxychilus(Atlantoxychilus) spectabilis (Milne-Edwards, 1885) (Gastropoda: Pulmonata) : a gametogenic approach

The taxonomic status and anatomy of Oxychilus (Atlantoxychilus) spectabilis (Milne-Edwards, 1885), an endemic land snail from Santa Maria Island, Azores, has been subject of detailed study, yet information about its life history is wanting. This study describes the reproductive cycle of O. (A.) spectabilis and assesses the validity of three morphometric shell parameters as maturation diagnostic characters. Our results indicate that individuals are reproductively more active from May to November. However, the availability of spermatozoa throughout the year and the residual values of mature oocytes during the remaining months seem to provide minimum conditions for reproduction all year round. The snail has a functional protandric tendency and gonadal maturation is initially triggered by photophase and after regulated by temperature. The positive correlation between gonadal maturation and morphometric shell characters indicate that these parameters might be a useful tool for the diagnosis of snail’s maturation

Sensors based on recycled optical fibers destroyed by the catastrophic fuse effect

In the last decades the fiber Bragg gratings (FBG) and Fabry-Perot Interferometer (FPI) micro cavities based sensors have become one of the most attractive optical fiber sensing technologies. However, its production requires a significant economical investment. We propose a cost effective solution based on micro cavity generated by the recycling of optical fibers destroyed through the catastrophic fuse effect. This technique considerably reduces the experimental complexity and the production costs. In this paper, the application of these sensors in the monitoring of several parameters, such as refractive index, pressure, strain and temperature is presented

In vivo biodistribution of carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles in rats

Carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles (CMCht/PAMAM) have recently been proposed for intracellular drug delivery purposes. These are constituted by a PAMAM dendrimer core grafted with chains of CMCht. Previous reports have shown that these nanoparticles disclosed an improved cytotoxic profile when compared to traditional dendrimers. Following on these results the present study aims to assess, for the first time, the short-term in vivo biodistribution of CMCht/PAMAM dendrimer nanoparticles upon intravenous injections in Wistar Han rats. The rats were injected in the tail vein with 1 and 10 µg/g, respectively, of fluorescein isothiocyanate (FITC) labeled CMCht/PAMAM dendrimer nanoparticles. Brain, liver, kidney and lung were collected at 24, 48 and 72 hours after injection and further stained with phalloidin-TRITC (red) and DAPI (blue) to trace the nanoparticles within the tissues. Liver, kidney and lung were also stained for haematoxylin and eosin in order to assess possible alterations in the morphology of these organs. CMCht/PAMAM dendrimer nanoparticles were observed within the vascular space and parenchyma of liver, kidney and lung, and in the choroid plexus, after 24, 48 and 72 hours upon intravenous injection of nanoparticles. No particles were observed in the brain parenchyma, nor any apparent deleterious histological changes, were observed within these organs. The present report revealed that CMCht/PAMAM dendrimer nanoparticles were stable in circulation for periods up to 72 hours, targeting the main organs/systems through internalization by the cells present in their parenchyma. These results provide positive indicators to their potential use in the future as intracellular drug delivery systems.Funds attributed by Fundação Calouste de Gulbenkian to A.J. Salgado under the scope of the The Gulbenkian Programme to Support Research in Life Sciences; Portuguese Foundation for Science and Technology (Science 2007 Program – A.J. Salgado, pre- and postdoctoral fellowships to J.M. Oliveira – SFRH/BPD/63175/2009, A.M. Frias – SFRH/BPD/45206/2008, F. Marques – SFRH/BPD/33379/2008, A.M. Falcão – SFRH/BD/44485/2008, S. Roque – SFRH/BD/24539/2005; S.R. Cerqueira – SFRH/BD/SFRH/BD/48406: 2008)

Response to comment on 'Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity'

Lambert et al. question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm that our study provides unambiguous evidence that chytridiomycosis has affected at least 501 amphibian species

The HIV-1 reservoir landscape in persistent elite controllers and transient elite controllers

FUNDING. Instituto de Salud Carlos III (FI17/00186, FI19/00083, MV20/00057, PI18/01532, PI19/01127 and PI22/01796), Gilead Fellowships (GLD22/00147). NIH grants AI155171, AI116228, AI078799, HL134539, DA047034, MH134823, amfAR ARCHE and the Bill and Melinda Gates Foundation.BACKGROUND. Persistent controllers (PCs) maintain antiretroviral-free HIV-1 control indefinitely over time, while transient controllers (TCs) eventually lose virological control. It is essential to characterize the quality of the HIV reservoir in terms of these phenotypes in order to identify the factors that lead to HIV progression and to open new avenues toward an HIV cure. METHODS. The characterization of HIV-1 reservoir from peripheral blood mononuclear cells was performed using next-generation sequencing techniques, such as full-length individual and matched integration site proviral sequencing (FLIP-Seq; MIP-Seq). RESULTS. PCs and TCs, before losing virological control, presented significantly lower total, intact, and defective proviruses compared with those of participants on antiretroviral therapy (ART). No differences were found in total and defective proviruses between PCs and TCs. However, intact provirus levels were lower in PCs compared with TCs; indeed the intact/defective HIV-DNA ratio was significantly higher in TCs. Clonally expanded intact proviruses were found only in PCs and located in centromeric satellite DNA or zinc-finger genes, both associated with heterochromatin features. In contrast, sampled intact proviruses were located in permissive genic euchromatic positions in TCs. CONCLUSIONS. These results suggest the need for, and can give guidance to, the design of future research to identify a distinct proviral landscape that may be associated with the persistent control of HIV-1 without ART.Instituto de Salud Carlos III (FI17/00186, FI19/00083, MV20/00057, PI18/01532, PI19/01127, PI22/01796)Gilead Fellowships (GLD22/00147)NIH grants AI155171, AI116228, AI078799, HL134539, DA047034, MH134823, amfAR ARCHEBill and Melinda Gates Foundatio

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality