The role of target membrane sialic acid residues in the fusion activity of the influenza virus: the effect of two types of ganglioside on the kinetics of membrane merging

The influenza virus enters target cells via the action of hemagglutinin proteins (HA) inserted into the viral envelope. HA promotes membrane fusion between the viral envelope and endosomal membrane at low pH, following viral binding to sialic acid-containing receptors on target cells, and internalization by endocytosis. The effect of target membrane sialic acid residues on the fusion activity of the influenza virus towards model membranes was evaluated by both reduction, (i.e. treating somatic cells with neuraminidase- (NA-) prior to virus-cell interactions), and by supplementing liposomes with the gangliosides GD1a and GT1b. The harshness of the neuraminidase pretreatment of target cells required to affect virus-induced membrane merging was found to greatly depend on the assay conditions, i.e. whether a virus-cell prebinding step at neutral pH was included prior to acidification. Minor concentrations of neuraminidase were found to greatly reduce virus fusion, but only in the absence of a prebinding step; they had no effect if this step was included. Although membrane merging was greatly reduced following cell neuraminidase pretreatment, virus-cell association at low pH was not disturbed proportionately. This probably reflects unspecific virus-cell binding under these conditions, probably of inactivated or aggregated virus particles, which does not translate into membrane merging. This seems to suggest both that target membrane sialic acid can protect the virus from losing its activity before triggering membrane merging, and that the importance of this interaction is not merely to ensure virus-target proximity. With liposomes, we found that both types of ganglioside supported efficient fusion, with GD1a promoting a slightly faster initial rate. However, in this case, virus-target proximity closely mirrored fusion activity, thus pointing to differential specificity between targets routinely used to assay influenza virus fusion activit

Seminal traits, suitability for semen preservation and fertility in the native Portuguese horse breeds Puro Sangue Lusitano and Sorraia: Implications for stallion classification and assisted reproduction

The Puro Sangue Lusitano (PSL) is the major national breed of horse in Portugal, but no studies exist on its seminal characteristics, or on the possibility of conserving semen for future use. The aim of this study was to evaluate semen parameters, fertility and the aptness to semen preservation in Lusitano Stallions. In order to compare characteristics defined by a single or by multiple semen collections per stallion 152 ejaculates obtained from 152 Lusitano stallions presented at an annual breeding soundness examination as well as data related to 371 ejaculates obtained from 9 PSL were analyzed. These latter samples were also evaluated in terms of their possible use in assisted reproduction and were compared with 113 ejaculates obtained from 4 Sorraia horses, a rare and endangered Portuguese breed. The percentage of motile spermatozoa (PMS) was assessed after collection (AC), after semen dilution (AD) and at 24 h of cool-storage. Mean values obtained for sperm motility and morphology and semen pH observed after semen collection differ significantly (P < 0.05) between single collection/multiple stallions and multiple collections/limited stallions, and no age related effects were detected. Overall, Lusitano semen quality was comparable to that of related breeds, while Sorraia stallions had very poor semen quality. The response to cool-storage of diluted semen samples differed among stallions and breeds, and the best results for progressive motile sperm cells at 24 h were in a range of 35-53% for PSL stallions and were lower for Sorraia stallions. Fertility rates obtained with artificial insemination (AI) averaged at 85% for PSL. With the exception of PMS AC, sperm vitality and semen pH no other seminal trait seemed to influence fertility rates in the Lusitano breed.http://www.sciencedirect.com/science/article/B6T43-4SPJ1TD-3/1/6a0fc54305a5730ccff6ba975a4abd0

Xenografting as a Tool to Preserve Endangered Species: Outcomes and Challenges in Model Systems

The use of testis tissue xenografting as a valuable tool to rescue endangered and genetically valuable individuals that die young or otherwise fail to produce sperm has been the subject of much interest. Although the technique has been successfully applied to a wide variety of species, little is known about what determines the outcome. Furthermore, to improve the applicability of xenografting, new methods to preserve and transport testis tissue from valuable animals are emerging. However, one major issue remains: the application of xenografting implies the development of subsequent ART techniques to produce offspring from the recovered material. This paper focuses on these three aspects of testis tissue xenografting as a tool for rescuing endangered and valuable genetic pools

Avaliação económica de programas de Reabilitação Respiratória em doentes respiratórios crónicos: impacto no Serviço Nacional de Saúde

Em Portugal, as doenças respiratórias crónicas, em particular a doença pulmonar obstrutiva cronica (DPOC), tem uma expressão significativa no quadro de doenças diagnosticadas. Face à escassez de recursos e ao aumento crescente das necessidades da população, a pressão sobre os serviços de saúde tem aumentado significativamente, pelo que se torna premente uma utilização eficiente dos recursos disponíveis para que, a custos razoáveis, seja possível obter verdadeiros ganhos em saúde. Assim, perceber qual o verdadeiro impacto económico no SNS decorrente da utilização eficiente de recursos no tratamento da DPOC, mais especificamente, a implementação de programas de reabilitação respiratória, é deveras relevante. De modo a proceder à avaliação económica deste tipo de programas, recorreu-se a modelos de simulação de Markov e análise custo-efectividade, onde para diferentes cenários hipotetizados foram relacionados os custos decorrentes destes programas com a sua efectividade, número de internamentos evitados, comparando com a terapêutica convencional. Através da análise de rácios incrementais custo-efectividade, verificou-se que os cenários hipotetizados são custo-efectivos, por apesar de apresentarem mais custos apresentarem também mais benefícios. No entanto, ao comparar o custo por internamento evitado com o custo de um internamento, este valor é bastante superior mesmo para o melhor cenário (9791,50€ vs. 4258,78€). Ao aumentar a eficácia da terapêutica estes rácios tornam-se mais aceitáveis, sendo para o melhor cenário, menores que o custo de internamento de um doente no estadio mais grave. Esta avaliação atende apenas ao impacto nos internamentos evitados, pelo que o real impacto da reabilitação respiratória se encontra subestimado, podendo ser avaliada à luz dessa mesma medida de efectividade.In Portugal, the burden of respiratory diseases, in particular the chronic obstructive respiratory disease, have a huge expression on the number of diagnosed diseases. Due to the lack of resourses and the increase of healthcare needs by the citzens, the pressure over the healthcare services has been significantly higher, so the need for an efficient use of the available resourses, at reasonable prices it’s urgent, in a way that it’s possible to obtain real health gains. Realize the true economic impact to the NHS, by the eficiente use of the resources in the treatment of COPD, more specificly the respiratory rehabilitation programs, is very importante. In order to procced with the eveluation of this health programs, were used Markov simulation models and cost-effectiveness analysis, in which for different scenarios, the costs of these programs were related to their effectivenesses, hospital admissions avoided, when compared to the convencional therapy. Through the analysis of the incremental cost-effectiveness ratios, it was foud that the hypothesized scenarios are cost-effective, because, although presenting more costs also present more benefits. However, when comparing the cost per hospital admisson avoided with the cost of an hospital admission, this figure is significantly higher, even for the best case scenario (9791,50€ vs. 4258,78€). By increasing the eficacy of the therapy, this rácios become more acceptable, and for the best case scenario, lower than an hospital admisson of a patient in the most severe stage. This evaluation only addresses the impact on avoided hospital admissions, so the real impact of respiratory rehebilitation programs are underestimated, and can only be assessed in light of that same measure of effectiveness

Acrosome components after intracytoplasmic sperm injection: the decondensation frontier

http://www.sciencedirect.com/science/article/B6T6K-43CBFGC-14/1/c122d3f8e7188ef9ec4a133a8068995

Virulence factors in carbapenem-resistant hypervirulent Klebsiella pneumoniae

Copyright © 2023 Mendes, Santos, Ramalho, Duarte and Caneiras. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Hypervirulence and carbapenem-resistant have emerged as two distinct evolutionary pathotypes of Klebsiella pneumoniae, with both reaching their epidemic success and posing a great threat to public health. However, as the boundaries separating these two pathotypes fade, we assist a worrisome convergence in certain high-risk clones, causing hospital outbreaks and challenging every therapeutic option available. To better understand the basic biology of these pathogens, this review aimed to describe the virulence factors and their distribution worldwide among carbapenem-resistant highly virulent or hypervirulent K. pneumoniae strains, as well as to understand the interplay of these virulence strains with the carbapenemase produced and the sequence type of such strains. As we witness a shift in healthcare settings where carbapenemresistant highly virulent or hypervirulent K. pneumoniae are beginning to emerge and replace classical K. pneumoniae strains, a better understanding of these strains is urgently needed for immediate and appropriate response.This research was partially funded by Fundação para a Ciência e a Tecnologia (FCT), under grant numbers UIDB/04295/2020 and UIDP/04295/2020. Moreover, CC acknowledges the funding provided by the “Research Award in Healthcare Associated Infections” granted by Escola Superior de Saúde Norte da Cruz Vermelha Portuguesa (2019) and by “BInov award,” an innovation award granted by the Southern Regional Section and Autonomous Regions of the Portuguese Pharmaceutical Society (2021). GM was supported by Fundação para a Ciência e Tecnologia (FCT), Portugal, through a Ph.D. Research Studentship Contract (Contrato de Bolsa de Investigação para Doutoramento 2020.07736.BD).info:eu-repo/semantics/publishedVersio

PALSAR-2/ALOS-2 AND OLI/LANDSAT-8 DATA INTEGRATION FOR LAND USE AND LAND COVER MAPPING IN NORTHERN BRAZILIAN AMAZON

In northern Brazilian Amazon, the crops, savannahs and rainforests form a complex landscape where land use and land cover (LULC) mapping is difficult. Here, data from the Operational Land Imager (OLI)/Landsat-8 and Phased Array type L-band Synthetic Aperture Radar (PALSAR-2)/ALOS-2 were combined for mapping 17 LULC classes using Random Forest (RF) during the dry season. The potential thematic accuracy of each dataset was assessed and compared with results of the hybrid classification from both datasets. The results showed that the combination of PALSAR-2 HH/HV amplitudes with the reflectance of the six OLI bands produced an overall accuracy of 83% and a Kappa of 0.81, which represented an improvement of 6% in relation to the RF classification derived solely from OLI data. The RF models using OLI multispectral metrics performed better than RF models using PALSAR-2 L-band dual polarization attributes. However, the major contribution of PALSAR-2 in the savannahs was to discriminate low biomass classes such as savannah grassland and wooded savannah

Lifelong Healthy Habits and Lifestyles

The expression “lifestyles” describes several expressed behaviors, usually in the form of consumption and behaviors patterns, which characterizes how an individual or group fits into society. Although, with the advancement of science and the facilitation of human tasks in the daily living, there is a reduction in mortality from infectious diseases and an increase in longevity, however the appearance of chronic-degenerative diseases that negatively affect the quality of life have been found when some behaviors, defined as “good” lifestyles are not considered. The lifestyles could be defined as a set of mediating structures that reflect a totality of activities, attitudes and social values ​​closely related and that depend on economic and social conditions, education, age, among other factors. It manifests historical and cultural experiences and emerges from a set of decisions, over which the subject assumes control, thus, the lifestyle is revealed to be fundamental in the promotion and protection of health. This chapter intends to describe how healthy lifestyles could be considered adequate through our living period since young ages, maintaining and distinguishing them during adulthood and making them useful in older ages

Testicular aging involves mitochondrial dysfunction as well as an increase in UCP2 levels and proton leak

http://www.sciencedirect.com/science/article/B6T36-4V1DJMK-4/2/e5e215dfcd6f54b36d458bf36b793db