553 research outputs found

    Nuevos datos de distribución de ranas de cristal (Amphibia: Centrolenidae) en el oriente de Ecuador, con comentarios sobre la diversidad en la región

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    We present new information on the latitudinal and altitudinal distribution of five species of recently-described or poorly-known glassfrogs from eastern Ecuador. We include novel data on its body size and natural history. Information on the diversity and biogeography of the centrolenid frogs of Eastern Ecuador is discussed, finding them associated with six vegetation formations distributed between the eastern Andean slopes and lowland Amazonia. We identify three important zones of diversity and endemism in Eastern Ecuador associated with the Napo, Pastaza, and Santiago river basins. The ecosystems of Low Montane and Foothill forests have the largest diversity and endemism of centrolenid frogs, however, 77% are threatened. It is vital to join effort to research and preserve this particular group of the Ecuadorian fauna.Presentamos nueva información que extiende la distribución latitudinal y altitudinal de cinco especies de ranas de cristal recientemente descritas y poco conocidas de la región oriental de Ecuador. Incluimos datos novedosos sobre su tamaño corporal e historia natural. Se discute información sobre la diversidad y biogeografía de ranas centrolenidas del oriente de Ecuador, encontrando que se encuentran asociadas con seis formaciones vegetales comprendidas entre las estribaciones orientales y la baja Amazonia. Identificamos tres importantes zonas de diversidad y endemismo en la región oriental de Ecuador asociadas con las cuencas hidrográficas de los ríos Napo, Pastaza y Santiago. Los ecosistemas de bosques Montano Bajos y Piemontanos concentran la mayor diversidad y endemismo para ranas centrolenidas, sin embargo 77% de ellas están amenazadas. Es trascendental juntar todos los esfuerzos posibles para investigar y conservar este substancial grupo de la fauna ecuatoriana

    Perspectives on the Trypanosoma cruzi-host cell receptor interaction

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    Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets

    Restoring cellular magnesium balance through Cyclin M4 protects against acetaminophen-induced liver damage

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    Acetaminophen overdose is one of the leading causes of acute liver failure and liver transplantation in the Western world. Magnesium is essential in several cellular processess. The Cyclin M family is involved in magnesium transport across cell membranes. Herein, we identify that among all magnesium transporters, only Cyclin M4 expression is upregulated in the liver of patients with acetaminophen overdose, with disturbances in magnesium serum levels. In the liver, acetaminophen interferes with the mitochondrial magnesium reservoir via Cyclin M4, affecting ATP production and reactive oxygen species generation, further boosting endoplasmic reticulum stress. Importantly, Cyclin M4 mutant T495I, which impairs magnesium flux, shows no effect. Finally, an accumulation of Cyclin M4 in endoplasmic reticulum is shown under hepatoxicity. Based on our studies in mice, silencing hepatic Cyclin M4 within the window of 6 to 24 h following acetaminophen overdose ingestion may represent a therapeutic target for acetaminophen overdose induced liver injury

    Ocular inflammatory events following COVID-19 vaccination: a multinational case series

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    Background: Inflammatory adverse events following COVID-19 vaccination are being reported amidst the growing concerns regarding vaccine’s immunogenicity and safety, especially in patients with pre-existing inflammatory conditions. Methods: Multinational case series of patients diagnosed with an ocular inflammatory event within 14 days following COVID-19 vaccination collected from 40 centres over a 3 month period in 2021. Results: Seventy patients presented with ocular inflammatory events within 14 days following COVID-19 vaccination. The mean age was 51 years (range, 19–84 years). The most common events were anterior uveitis (n = 41, 58.6%), followed by posterior uveitis (n = 9, 12.9%) and scleritis (n = 7, 10.0%). The mean time to event was 5 days and 6 days (range, 1–14 days) after the first and second dose of vaccine, respectively. Among all patients, 36 (54.1%) had a previous history of ocular inflammatory event. Most patients (n = 48, 68.6%) were managed with topical corticosteroids. Final vision was not affected in 65 (92.9%), whereas 2 (2.9%) and 3 (4.3%) had reduction in visual acuity reduced by ≤3 lines and > 3 lines, respectively. Reported complications included nummular corneal lesions (n = 1, 1.4%), cystoid macular oedema (n = 2, 2.9%) and macular scarring (n = 2, 2.9%). Conclusion: Ocular inflammatory events may occur after COVID-19 vaccination. The findings are based on a temporal association that does not prove causality. Even in the possibility of a causal association, most of the events were mild and had a good visual outcome

    Land-use change and carbon stocks: regional assessment of sugarcane areas in Brazil.

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    Abstract: In agricultural product Life Cycle Assessment (LCA), emissions or removals of carbon (C) from land-use change can highly affect the global warming. The aim of this study was to evaluate the impacts of biomass C values and stock change factors on land use change (LUC) emissions in areas of sugarcane expansion in Brazil. In this study, we used stratified random sample in order to estimate changes in land cover through geotechnologies and associated C stocks from literature data. For that, the total area was stratified by three criteria: soil type, % of native vegetation in 1998 and age of sugarcane plantation in 2018. The sample size represented 12.8% of the studied area (172,000 ha). To this end, a matrix of primary combinations was combined with spatial data such as land cover in 1998, soil types, biomes and Köppen climate classification. Estimates of C stock changes in soil and biomass were calculated the Stock-Difference Method, according to IPCC Guidelines and specialized literature. Respecting the uncertainties, this approach allowed to have an estimate of C balance in sugarcane fields at the regional level in Brazil. Three main recommendations: (i) values of FMG> 1.0 (FMG, stock change factor for management regime), should be used for sugarcane, but future research ratification is necessary; (ii) biomass C values of sugarcane biomass above 5 tonnes C ha-1 should be used, especially when sugarcane is harvested without burning; and (iii) as there is still no relationship between level of pasture degradation and C content in soil, biomass C values and pasture FMG should be carefully chosen in pasture conversion to sugarcane

    PESCADOR, a web-based tool to assist text-mining of biointeractions extracted from PubMed queries

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    BACKGROUND: Biological function is greatly dependent on the interactions of proteins with other proteins and genes. Abstracts from the biomedical literature stored in the NCBI's PubMed database can be used for the derivation of interactions between genes and proteins by identifying the co-occurrences of their terms. Often, the amount of interactions obtained through such an approach is large and may mix processes occurring in different contexts. Current tools do not allow studying these data with a focus on concepts of relevance to a user, for example, interactions related to a disease or to a biological mechanism such as protein aggregation. RESULTS: To help the concept-oriented exploration of such data we developed PESCADOR, a web tool that extracts a network of interactions from a set of PubMed abstracts given by a user, and allows filtering the interaction network according to user-defined concepts. We illustrate its use in exploring protein aggregation in neurodegenerative disease and in the expansion of pathways associated to colon cancer. CONCLUSIONS: PESCADOR is a platform independent web resource available at: http://cbdm.mdc-berlin.de/tools/pescador

    Non-capsulated and capsulated Haemophilus influenzae in children with acute otitis media in Venezuela: a prospective epidemiological study

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    <p>Abstract</p> <p>Background</p> <p>Non-typeable <it>Haemophilus influenzae </it>(NTHi) and <it>Streptococcus pneumoniae </it>are major causes of bacterial acute otitis media (AOM). Data regarding AOM are limited in Latin America. This is the first active surveillance in a private setting in Venezuela to characterize the bacterial etiology of AOM in children < 5 years of age.</p> <p>Methods</p> <p>Between December 2008 and December 2009, 91 AOM episodes (including sporadic, recurrent and treatment failures) were studied in 87 children enrolled into a medical center in Caracas, Venezuela. Middle ear fluid samples were collected either by tympanocentesis or spontaneous otorrhea swab sampling method. Standard laboratory and microbiological techniques were used to identify bacteria and test for antimicrobial resistance. The results were interpreted according to Clinical Laboratory Standards Institute (CLSI) 2009 for non-meningitis isolates. All statistical analyses were performed using SAS 9.1 and Microsoft Excel (for graphical purposes).</p> <p>Results</p> <p>Overall, bacteria were cultured from 69.2% (63 of the 91 episodes); at least one pathogen (<it>S. pneumoniae, H. influenzae, S. pyogenes </it>or <it>M. catarrhalis</it>) was cultured from 65.9% (60/91) of episodes. <it>H. influenzae </it>(55.5%; 35/63 episodes) and <it>S. pneumoniae </it>(34.9%; 22/63 episodes) were the most frequently reported bacteria. Among <it>H. influenzae </it>isolates, 62.9% (22/35 episodes) were non-capsulated (NTHi) and 31.4% (11/35 episodes) were capsulated including types d, a, c and f, across all age groups. Low antibiotic resistance for <it>H. influenzae </it>was observed to amoxicillin/ampicillin (5.7%; 2/35 samples). NTHi was isolated in four of the six <it>H. influenzae </it>positive samples (66.7%) from recurrent episodes.</p> <p>Conclusions</p> <p>We found <it>H. influenzae </it>and <it>S. pneumoniae </it>to be the main pathogens causing AOM in Venezuela. Pneumococcal conjugate vaccines with efficacy against these bacterial pathogens may have the potential to maximize protection against AOM.</p

    Effectiveness and safety of first-generation protease inhibitors in clinical practice: Hepatitis C virus patients with advanced fibrosis

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    AIM: To evaluates the effectiveness and safety of the first generation, NS3/4A protease inhibitors (PIs) in clinical practice against chronic C virus, especially in patients with advanced fibrosis. METHODS: Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1, treatment-nai¨ve (TN) or treatment-experienced (TE), who underwent triple therapy with the first generation NS3/4A protease inhibitors, boceprevir (BOC) and telaprevir (TVR), in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow up. RESULTS: One thousand and fifty seven patients were included, 405 (38%) were treated with BOC and 652 (62%) with TVR. Of this total, 30% (n = 319) were TN and the remaining were TE: 28% (n = 298) relapsers, 12% (n = 123) partial responders (PR), 25% (n = 260) null-responders (NR) and for 5% (n = 57) with prior response unknown. The rate of sustained virologic response (SVR) by intention-to-treatment (ITT) was greater in those treated with TVR (65%) than in those treated with BOC (52%) (P < 0.0001), whereas by modified intention-to-treatment (mITT) no were found significant differences. By degree of fibrosis, 56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients, both TN and TE. In the analysis by groups, the TN patients treated with TVR by ITT showed a higher SVR (P = 0.005). However, by mITT there were no significant differences between BOC and TVR. In the multivariate analysis by mITT, the significant SVR factors were relapsers, IL28B CC and non-F4; the type of treatment (BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients, treated with BOC (46%) or with TVR (45%). 28% of the patients interrupted the treatment, mainly by non-viral response (51%): this outcome was more frequent in the TE than in the TN patients (57% vs 40%, P = 0.01). With respect to severe haematological disorders, neutropaenia was more likely to affect the patients treated with BOC (33% vs 20%, P = 0.0001), and thrombocytopaenia and anaemia, the F4 patients (P = 0.000, P = 0.025, respectively). CONCLUSION: In a real clinical practice setting with a high proportion of patients with advanced fibrosis, effectiveness of first-generation PIs was high except for NR patients, with similar SVR rates being achieved by BOC and TVR

    The genetic determinants of recurrent somatic mutations in 43,693 blood genomes

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    Nononcogenic somatic mutations are thought to be uncommon and inconsequential. To test this, we analyzed 43,693 National Heart, Lung and Blood Institute Trans-Omics for Precision Medicine blood whole genomes from 37 cohorts and identified 7131 non-missense somatic mutations that are recurrently mutated in at least 50 individuals. These recurrent non-missense somatic mutations (RNMSMs) are not clearly explained by other clonal phenomena such as clonal hematopoiesis. RNMSM prevalence increased with age, with an average 50-year-old having 27 RNMSMs. Inherited germline variation associated with RNMSM acquisition. These variants were found in genes involved in adaptive immune function, proinflammatory cytokine production, and lymphoid lineage commitment. In addition, the presence of eight specific RNMSMs associated with blood cell traits at effect sizes comparable to Mendelian genetic mutations. Overall, we found that somatic mutations in blood are an unexpectedly common phenomenon with ancestry-specific determinants and human health consequences
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