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921.
da Rosa Cristiano Niederauer Pereira Filho Waterloo Bremer Ulisses Franz Putzke Jair de Andrade André Medeiros Kramer Gisieli Hillebrand Fernando Luis de Jesus Janisson Batista 《Biodiversity and Conservation》2022,31(7):1887-1892
Biodiversity and Conservation - 相似文献
922.
Rafael Almeida Paiva Tania Martins‐Marques Katia Jesus Teresa Ribeiro‐Rodrigues Monica Zuzarte Ana Silva Liliana Reis Maria da Silva Paulo Pereira Pieter Vader Joost Petrus Gerardus Sluijter Lino Gonalves Maria Teresa Cruz Henrique Girao 《Journal of cellular and molecular medicine》2019,23(2):1137-1151
Myocardial ischaemia is associated with an exacerbated inflammatory response, as well as with a deregulation of intercellular communication systems. Macrophages have been implicated in the maintenance of heart homeostasis and in the progression and resolution of the ischaemic injury. Nevertheless, the mechanisms underlying the crosstalk between cardiomyocytes and macrophages remain largely underexplored. Extracellular vesicles (EVs) have emerged as key players of cell‐cell communication in cardiac health and disease. Hence, the main objective of this study was to characterize the impact of cardiomyocyte‐derived EVs upon macrophage activation. Results obtained demonstrate that EVs released by H9c2 cells induced a pro‐inflammatory profile in macrophages, via p38MAPK activation and increased expression of iNOS, IL‐1β and IL‐6, being these effects less pronounced with ischaemic EVs. EVs derived from neonatal cardiomyocytes, maintained either in control or ischaemia, induced a similar pattern of p38MAPK activation, expression of iNOS, IL‐1β, IL‐6, IL‐10 and TNFα. Importantly, adhesion of macrophages to fibronectin was enhanced by EVs released by cardiomyocytes under ischaemia, whereas phagocytic capacity and adhesion to cardiomyocytes were higher in macrophages incubated with control EVs. Additionally, serum‐circulating EVs isolated from human controls or acute myocardial infarction patients induce macrophage activation. According to our model, in basal conditions, cardiomyocyte‐derived EVs maintain a macrophage profile that ensure heart homeostasis, whereas during ischaemia, this crosstalk is affected, likely impacting healing and post‐infarction remodelling. 相似文献
923.
Phylogeny of Gracilariaceae (Rhodophyta): evidence from plastid and mitochondrial nucleotide sequences
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Goia de M. Lyra Emmanuelle da S. Costa Priscila B. de Jesus João Carlos G. de Matos Taiara A. Caires Mariana C. Oliveira Eurico C. Oliveira Zhenxiang Xi José Marcos de C. Nunes Charles C. Davis 《Journal of phycology》2015,51(2):356-366
Gracilariaceae are mostly pantropical red algae and include ~230 species in seven genera. Infrafamilial classification of the group has long been based on reproductive characters, but previous phylogenies have shown that traditionally circumscribed groups are not monophyletic. We performed phylogenetic analyses using two plastid (universal plastid amplicon and rbcL) and one mitochondrial (cox1) loci from a greatly expanded number of taxa to better assess generic relationships and understand patterns of character distributions. Our analyses produce the most well‐supported phylogeny of the family to date, and indicate that key characteristics of spermatangia and cystocarp type do not delineate genera as commonly suggested. Our results further indicate that Hydropuntia is not monophyletic. Given their morphological overlap with closely related members of Gracilaria, we propose that Hydropuntia be synonymized with the former. Our results additionally expand the known ranges of several Gracilariaceae species to include Brazil. Lastly, we demonstrate that the recently described Gracilaria yoneshigueana should be synonymized as G. domingensis based on morphological and molecular characters. These results demonstrate the utility of DNA barcoding for understanding poorly known and fragmentary materials of cryptic red algae. 相似文献
924.
Rafael González-Alvarez María de Lourdes Garza-Rodríguez Iván Delgado-Enciso Víctor Manuel Trevi?o-Alvarado Ricardo Canales-Del-Castillo Laura Elia Martínez-De-Villarreal ángel Lugo-Trampe María Elizabeth Tejero Natalia E. Schlabritz-Loutsevitch María Del Refugio Rocha-Piza?a Shelley A. Cole Diana Reséndez-Pérez Mario Moises-Alvarez Anthony G. Comuzzie Hugo Alberto Barrera-Salda?a Raquel Garza-Guajardo Oralia Barboza-Quintana Irám Pablo Rodríguez-Sánchez 《Biological research》2015,48(1)
925.
926.
Paula Lopez Roa Maria Jesus Perez-Granda Patricia Munoz Pilar Catalan Roberto Alonso Eduardo Sanchez-Perez Emma Novoa Emilio Bouza 《PloS one》2015,10(6)
Background
Reactivation of cytomegalovirus (CMV) has been reported occasionally in immnunocompetent patients in the intensive care unit (ICU). The epidemiology and association of CMV infection with adverse outcome is not well defined in this population. Patients undergoing major heart surgery (MHS) are at a particularly high risk of infection. CMV infection has not been systematically monitored in MSH-ICU patients.Methods
We assessed CMV plasma viremia weekly using a quantitative polymerase chain reaction assay in a prospective cohort of immunocompetent adults admitted to the MHS-ICU for at least 72 hours between October 2012 and May 2013. Risk factors for CMV infection and its potential association with continued hospitalization or death by day 30 (composited endpoint) were assessed using univariate and multivariate logistic regression analyses.Results
CMV viremia at any level was recorded in 16.5% of patients at a median of 17 days (range, 3-54 days) after admission to the MHS-ICU. Diabetes (adjusted OR, 5.6; 95% CI, 1.8-17.4; p=0.003) and transfusion requirement (>10 units) (adjusted OR, 13.7; 95% CI, 3.9-47.8; p<0.001) were independent risk factors associated with CMV reactivation. Reactivation of CMV at any level was independently associated with the composite endpoint (adjusted OR, 12.1; 95% CI, 2.3-64; p=0.003).Conclusion
Reactivation of CMV is relatively frequent in immunocompetent patients undergoing MHS and is associated with prolonged hospitalization or death. 相似文献927.
Joel M Kremer Alan J Kivitz Jesus A Simon-Campos Evgeny L Nasonov Hans-Peter Tony Soo-Kon Lee Bonnie Vlahos Constance Hammond Jack Bukowski Huihua Li Seth L Schulman Susan Raber Andrea Zuckerman John D Isaacs 《Arthritis research & therapy》2015,17(1)
IntroductionTofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). During the clinical development programme, increases in mean serum creatinine (SCr) of approximately 0.07 mg/dL and 0.08 mg/dL were observed which plateaued early. This study assessed changes in measured glomerular filtration rate (mGFR) with tofacitinib relative to placebo in patients with active RA.MethodsThis was a randomised, placebo-controlled, Phase 1 study (). Patients were aged ≥18 years with active RA. Patients were randomised 2:1 to oral tofacitinib 10 mg twice daily (BID) in Period 1 then placebo BID in Period 2 (tofacitinib → placebo); or oral placebo BID in both Periods (placebo → placebo). Change in mGFR was evaluated by iohexol serum clearance at four time points (run-in, pre-dose in Period 1, Period 1 end, and Period 2 end). The primary endpoint was the change in mGFR from baseline to Period 1 end. Secondary endpoints included: change in mGFR at other time points; change in estimated GFR (eGFR; Cockcroft–Gault equation) and SCr; efficacy; and safety.Results148 patients were randomised to tofacitinib → placebo (N = 97) or placebo → placebo (N = 51). Baseline characteristics were similar between groups. A reduction of 8% (90% confidence interval [CI]: 2%, 14%) from baseline in adjusted geometric mean mGFR was observed during tofacitinib treatment in Period 1 vs placebo. During Period 2, mean mGFR returned towards baseline during placebo treatment, and there was no difference between the two treatment groups at the end of the study – ratio (tofacitinib → placebo/placebo → placebo) of adjusted geometric mean fold change of mGFR was 1.04 (90% CI: 0.97, 1.11). Post-hoc analyses, focussed on mGFR variability in placebo → placebo patients, were consistent with this conclusion. At study end, similar results were observed for eGFR and SCr. Clinical efficacy and safety were consistent with prior studies.ConclusionIncreases in mean SCr and decreases in eGFR in tofacitinib-treated patients with RA may occur in parallel with decreases in mean mGFR; mGFR returned towards baseline after tofacitinib discontinuation, with no significant difference vs placebo, even after post-hoc analyses. Safety monitoring will continue in ongoing and future clinical studies and routine pharmacovigilance. NCT01484561
Trial registration
Clinicaltrials.gov . Registered 30 November 2011. NCT01484561Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0612-7) contains supplementary material, which is available to authorized users. 相似文献928.
Antonio G. Pacheco Beatriz Grinsztejn Maria de Jesus M. da Fonseca Ronaldo I. Moreira Valdiléa G. Veloso Ruth K. Friedman Marilia Santini-Oliveira Sandra W. Cardoso Melissa Falc?o José G. Mill Isabela Bensenor Paulo Lotufo Dóra Chor 《PloS one》2015,10(2)
BackgroundCombination antiretroviral therapy (cART) had a dramatic impact on the mortality profile in human immunodeficiency virus (HIV) infected individuals and increased their life-expectancy. Conditions associated with the aging process have been diagnosed more frequently among HIV-infected patients, particularly, cardiovascular diseases.MethodsPatients followed in the Instituto de Pesquisa Clínica Evandro Chagas (IPEC) prospective cohort in Rio de Janeiro were submitted to the general procedures from the Brazilian Longitudinal Study of Adult Health, comprising several anthropometric, laboratory and imaging data. Carotid intima-media thickness (cIMT) was measured by ultrasonography, following the Mannheim protocol. Linear regression and proportional odds models were used to compare groups and covariables in respect to cIMT. The best model was chosen with the adaptive lasso procedure.ResultsA valid cIMT exam was available for 591 patients. Median cIMT was significantly larger for men than women (0.56mm vs. 0.53mm; p = 0.002; overall = 0.54mm). In univariable linear regression analysis, both traditional risk factors for cardiovascular diseases (CVD) and HIV-specific characteristics were significantly associated with cIMT values, but the best multivariable model chosen included only traditional characteristics. Hypertension presented the strongest association with higher cIMT terciles (OR = 2.51; 95%CI = 1.69–3.73), followed by current smoking (OR = 1,82; 95%CI = 1.19–2.79), family history of acute myocardial infarction or stroke (OR = 1.60; 95%CI = 1.10–2.32) and age (OR per year = 1.12; 95%CI = 1.10–1.14).ConclusionsOur results show that traditional cardiovascular disease (CVD) risk factors are the major players in determining increased cIMT among HIV infected patients in Brazil. This finding reinforces the need for thorough assessment of those risk factors in these patients to guarantee the incidence of CVD events remain under control. 相似文献
929.
Lara Pena-Bello Sonia Pertega-Diaz Elena Outeiri?o-Blanco Jesus Garcia-Buela Sulay Tovar Susana Sangiao-Alvarellos Carlos Dieguez Fernando Cordido 《PloS one》2015,10(3)
Context
Metabolic substrates and nutritional status play a major role in growth hormone (GH) secretion. Uncovering the mechanisms involved in GH secretion following oral glucose (OG) administration in normal and obese patients is a pending issue.Objective
The aim of this study was to investigate GH after OG in relation with adiposity, insulin secretion and action, and ghrelin secretion in obese and healthy women, to further elucidate the mechanism of GH secretion after OG and the altered GH secretion in obesity.Participants and Methods
We included 64 healthy and obese women. After an overnight fast, 75 g of OG were administered; GH, glucose, insulin and ghrelin were obtained during 300 minutes. Insulin secretion and action indices and the area under the curve (AUC) were calculated for GH, glucose, insulin and ghrelin. Univariate and multivariate linear regression analyses were employed.Results
The AUC of GH (μg/L•min) was lower in obese (249.8±41.8) than in healthy women (490.4±74.6), P=0.001. The AUC of total ghrelin (pg/mL•min) was lower in obese (240995.5±11094.2) than in healthy women (340797.5±37757.5), P=0.042. There were significant correlations between GH secretion and the different adiposity, insulin secretion and action, and ghrelin secretion indices. After multivariate analysis only ghrelin AUC remained a significant predictor for fasting and peak GH. 相似文献930.
Nieto A Cabrera CM Catalina P Cobo F Barnie A Cortés JL Barroso del Jesus A Montes R Concha A 《Cell biology international》2007,31(3):269-278
Mitomycin C (MMC) treatment has been used to arrest cell proliferation but not much is known about the effect of MMC on human foreskin fibroblasts (HFF) used as feeders for human embryonic stem cells (hESC). We tested the ability of MMC to stop the proliferation of HFF and to induce apoptosis. MMC inhibited the proliferation of HFF at 10 microg/ml over 2.5h of MMC treatment showing a decrease in the proliferation index measured by Ki-67 and S and G2/M phases related to active HFF. A low percentage of cells showed necrotic or apoptotic features using different lengths of incubation. Over time, the majority of cells remained in a mitotically inactive state. The percentage of apoptotic cells increased from day 2 to day 10, at the same time as the necrotic ones increased. The HS181 hESC line grew in an undifferentiated state on inactive HFF throughout the study. 相似文献