52 research outputs found
Efficacy of biomaterials for lateral bone augmentation performed with guided bone regeneration. A network meta-analysis.
Bone regeneration is often required concomitant with implant placement to treat a bone fenestration, a dehiscence, and for contouring. This systematic review assessed the impact of different biomaterials employed for guided bone regeneration (GBR) simultaneous to implant placement on the stability of radiographic peri-implant bone levels at ≥12 months of follow-up (focused question 1), as well as on bone defect dimension (width/height) changes at re-assessment after ≥4 months (focused question 2). Only randomized controlled trials (RCTs) and controlled clinical trials (CCTs) that compared different biomaterials for GBR were considered. A Bayesian network meta-analysis (NMA) was performed using a random-effects model. A ranking probability between treatments was obtained, as well as an estimation of the surface under the cumulative ranking value (SUCRA). Overall, whenever the biological principle of GBR was followed, regeneration occurred in a predictable way, irrespective of the type of biomaterial used. A lower efficacy of GBR treatments was suggested for initially large defects, despite the trend did not reach statistical significance. Regardless of the biomaterial employed, a certain resorption of the augmented bone was observed overtime. While GBR was shown to be a safe and predictable treatment, several complications (including exposure, infection, and soft tissue dehiscence) were reported, which tend to be higher when using cross-linked collagen membranes
Novo neonicotinóide associado a regulador de crescimento de insetos, no controle da mosca-branca e do pulgão na cultura do algodão.
Resumo: O objetivo deste trabalho foi avaliar o desempenho da nova molécula química dinotefuram, pertencente ao grupo dos neonicotinóides, associada a um análogo do hormônio juvenil (piriproxifem), em aplicação foliar, no controle da mosca-branca B. tabaci Biótipo B e do pulgão A. gossypii, em algodoeiro. O delineamento foi em blocos ao acaso com quatro repetições. Os tratamentos foram: testemunha, dinotefuram + piriproxifem a 25 + 12,5; 50 + 12,5; 75 + 12,5; 25 + 25; 50 + 25; 75 + 25 e dinotefuram a 75 g i.a./ha. Cada parcela foi de 48m2. Para aplicação foliar, utilizou-se um pulverizador costal equipado com barra contendo seis pontas cônicas (TXVK-8), propelido por CO2 e volume de 200 L/ha. Foram realizadas avaliações de eficiência dos tratamentos aos 0, 5, 10, 15 e 20 dias após a aplicação, contando-se o número de ninfas de mosca-branca e o número de pulgões em 10 folhas por parcela. Pela análise dos resultados, concluiu-se que o inseticida dinotefuram associado ao piriproxifem, foi eficiente no controle de ninfas de mosca-branca e do pulgão, igualando-se aos padrões já utilizados
Emprego de bloqueador seletivo de alimentação (Pimetrozine), no controle do bicudo-do-algodoeiro, Anthonomus grandis (Coleoptera:curculionidae), na cultura do algodão.
Longitudinal analysis of DC subsets in patients with ovarian cancer: Implications for immunotherapy.
The use of circulating cDC1 to generate anti-cancer vaccines is among the most promising approaches to overcome the limited immunogenicity and clinical efficacy of monocyte-derived DC. However, the recurrent lymphopenia and the reduction of DC numbers and functionality in patients with cancer may represent an important limitation of such approach. In patients with ovarian cancer (OvC) that had received chemotherapy, we previously showed that cDC1 frequency and function were reduced.
We recruited healthy donors (HD, n=7) and patients with OvC at diagnosis and undergoing interval debulking surgery (IDS, n=6), primary debulking surgery (PDS, n=6) or at relapse (n=8). We characterized longitudinally phenotypic and functional properties of peripheral DC subsets by multiparametric flow cytometry.
We show that the frequency of cDC1 and the total CD141+ DC capacity to take up antigen are not reduced at the diagnosis, while their TLR3 responsiveness is partially impaired in comparison with HD. Chemotherapy causes cDC1 depletion and increase in cDC2 frequency, but mainly in patients belonging to the PDS group, while in the IDS group both total lymphocytes and cDC1 are preserved. The capacity of total CD141 <sup>+</sup> DC and cDC2 to take up antigen is not impacted by chemotherapy, while the activation capacity upon Poly(I:C) (TLR3L) stimulation is further decreased.
Our study provides new information about the impact of chemotherapy on the immune system of patients with OvC and sheds a new light on the importance of considering timing with respect to chemotherapy when designing new vaccination strategies that aim at withdrawing or targeting specific DC subsets
Combining eutectic solvents and pressurized liquid extraction coupled in-line with solid-phase extraction to recover, purify and stabilize anthocyanins from Brazilian berry waste
Pressurized techniques are straightforward for high-scale applications and highly controllable, which seems an excellent strategy for recovering unstable natural compounds. In this work, the main advance was the development of a platform based on the pressurized liquid extraction coupled in-line with a solid-phase extraction step (PLE-SPE) combined with the use of eutectic mixtures as solvents to promote an efficient extraction and purification of natural pigments from food wastes. Eutectic mixtures, conventionally known as (deep) eutectic solvents – (D)ES, are combinations of two or more substances with a lower melting point than any of their components. (D)ES are often referred as “green solvents” because they can potentially be more environmentally friendly than other solvents, especially volatile organic solvents (VOSs). Overall, (D)ES have the potential to contribute to the achievement of several of the SDGs (especially 3, 13, and 14) through their positive impacts on health, environment, and sustainable production and consumption practices. Thus, in this work, (D)ES were used as solvents to valorize Brazilian berry waste (Plinia cauliflora). Anthocyanins are the biomass's main compounds of commercial interest, mainly for food and cosmetic applications. However, there are several technological issues regarding color control due to their high sensitivity to light, heat, oxygen, and pH variations. Thus, the data achieved in this work highlighted the high efficiency and low environmental footprint of the PLE-SPE-(D)ES platform developed. The success of the downstream process here developed was proved by the high extraction efficiency and the purity level of the anthocyanins obtained. Besides, thermal stability analysis was evaluated, demonstrating that (D)ES are not only solvents but also stabilizing agents, improving the shelf-life of the extracted colorants.publishe
Previsão probabilística de enchentes para uma pequena bacia hidrográfica do Pantanal.
O monitoramento para a previsão de cheias de pequenas bacias hidrográficas é de grande importância tendo em vista a relação dos recursos hídricos com a sociedade, pois pode garantir o uso sustentável às comunidades urbanas de cidades lindeiras à bacia. O rio Aquidauana está inserido na planície Pantaneira sendo considerado vulnerável à inundações, no entanto, falta de um sistema eficiente para previsões de cheias e inundações. Assim, este estudo propõe um sistema de previsão probalística de enchentes para a bacia do Rio Aquidauana. Para tanto foram utilizadas as redes neurais artificiais (RNAs) do tipo MultiLayer Perceptron (treinamento backpropagation) com parâmetros otimizados pelos Algoritmos Genéticos. A RNA foi treinada e avaliada com base em dados de chuva acumulada (mm) e nível de rio (cm) à montante entre os anos de 1995 a 2014. A previsão realizada foi de 1 a 5 dias, tendo como melhor desempenho o modelo para 1 dia de previsão, com resultado de coeficiente de determinação e erro quadrático médio de 0,93 e 30 (cm), respectivamente
Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.
In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field
Pesquisa clínica em saúde mental: o ponto de vista dos usuários sobre a experiência de ouvir vozes
Analysis of antiviral immunity in primary and chronic infections
Several evidences in humans underscored the contribution of CD4 and CD8 T-cell responses in controlling viral and bacterial infections. However, CD4 and CD8 Τ cells have distinct and specific effector functions leading to a hierarchical importance in responding to different types of pathogens. In this context, the present work aimed to investigate distinct CD8 T-cell features potentially influencing T-cell efficacy against viral infection. To achieve this-objective, CD8 Τ cells derived from HIV-infected patients and healthy donors harbouring virus-specific immune responses or immunized with an HTV vaccine candidate were studied.
In particular, we performed a comprehensive cross-sectional and longitudinal analysis to characterize the function, the phenotype and the functional avidity of HIV-specific CD8 Τ cells during acute (PHI) and chronic infection and, in particular, we investigated immunological parameters potentially associated with the functional avidity of HIV-specific CD8 Τ cells. In addition, we studied the expression pattern of co-inhibitory molecules and the influence of CD 160 on the functions of CD8 Τ cells in absence of chronic infections.
From these analyses we observed that the functional avidity of HIV-specific CD8 T- cell responses was significantly lower in acute than in chronic infection, but was not different between chronic progressive and non-progressive patients. Functional avidity remained low after several years of antiretroviral therapy in PHI patients, but increased in patients experiencing a virus rebound following treatment interruption in association with a massive renewal of the global CD8 complementarity-determining region 3 of the TCR. The functional avidity was also directly associated to T-cell exhaustion.
In individuals with no sign of HIV or Hepatitis A, Β or C virus infection, CD8 Τ cells expressed higher levels of co-inhibitory molecules than CD4 Τ cells and this was dependent on the stage of T-cell differentiation and activation. The expression of CD 160 impaired the proliferation capacity and IL-2 production of CD8 Τ cells and was reduced upon CD8 T-cell activation, entitling CD 160 as unique marker of CD8 T-cell exhaustion. The CD 160 blockade restored the proliferation capacity of virus-specific CD8 Τ cells providing a potential new target for immunotherapy.
All together, these results expand our knowledge regarding the interplay between the immune system and the viruses.
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De nombreuses études chez l'Homme ont mis en évidence la contribution des réponses cellulaires Τ CD4 et CD8 dans le contrôle des infections virales et bactériennes. En particulier, les lymphocytes Τ ont différentes fonctions effectrices spécifiques qui leur confèrent un rôle clé lors d'infections par différents pathogènes. Ce travail vise à étudier différentes caractéristiques des cellules Τ CD8 affectant l'efficacité des réponses cellulaires contre les virus. Pour atteindre cet objectif nous avons étudié les cellules Τ CD8 provenant de patients infectés par le VIH et de donneurs sains avec des réponses immunitaires naturelles ou vaccinales contre des virus.
Nous avons effectué plusieurs analyses transversales et longitudinales des fonctions, du phénotype et de l'avidité fonctionnelle des lymphocytes Τ CD8 spécifiques au VIH au cours d'infections aiguës et chroniques; en particulier, nous avons étudié les paramètres immunologiques qui pourraient être associés à l'avidité fonctionnelle. De plus, nous avons investigué le profil d'expression des principales molécules co-inhibitrices et en particulier le rôle du CD 160 dans les fonctions des lymphocytes Τ CD8.
Sur la base de ces analyses, nous avons constaté que l'avidité fonctionnelle des cellules Τ CD8 spécifiques au VIH était significativement plus faible lors infections aiguës que lors d'infections chroniques, mais n'était, par contre, pas différente entre les patients avec des infections chroniques progressives et non progressives. L'avidité fonctionnelle reste faible après plusieurs années de traitement antirétroviral, mais augmente chez les patients subissant un rebond viral, et donc exposés à des hautes virémies, suite à l'interruption du traitement. Cette augmentation d'avidité des lymphocytes Τ CD8, liée à un épuisement fonctionnel accru, était quantitativement directement associée à un renouvellement massif du TCR.
Indépendamment de l'infection par le VIH, les cellules Τ CD8 expriment des niveaux plus élevés de molécules co-inhibitrices (PD-1, 2B4 et CD 160) par rapport aux cellules Τ CD4 et ceci dépend de leur stade de différenciation et d'activation. En particulier, CD 160 semble être un marqueur clé d'épuisement cellulaire des cellules Τ CD8, et donc une nouvelle cible potentielle pour l'immunothérapie, car a) son expression réduit la capacité proliférative et la production d'IL-2 b) CD 160 diminue suite à 1'activation et c) le blocage de CD 160 redonne la capacité proliférative aux cellules Τ CD8 spécifiques aux virus.
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Le système immunitaire est un ensemble de cellules, tissus et organes indispensables pour limiter l'entrée des pathogènes à travers la peau et les muqueuses. Parmi les différentes cellules composant le système immunitaire, les cellules Τ CD4 et CD8 sont fondamentales pour le contrôle des infections virales et bactériennes. Les moyens pour combattre les différents pathogènes peuvent être cependant très variables.
Les cellules Τ CD8, qui sont indispensables pour la lutte contre les virus, peuvent avoir différents niveaux de sensibilité; les cellules qui répondent à de faibles quantités d'antigène ont une forte sensibilité. Suite à une première infection virale, les cellules Τ CD8 ont une sensibilité plus faible que lors d'expositions répétées au même virus. En effet, la réexposition au pathogène induit une augmentation de sensibilité, grâce au recrutement et/ou à l'expansion de cellules Τ dotées d'une sensibilité plus élevée. Les cellules Τ CD8 avec une plus haute sensibilité semblent être caractérisées par une perte de fonctionnalité (épuisement fonctionnel associé à une haute expression de molécules dites inhibitrices).
En absence d'infection, la fonction des molécules inhibitrices n'est pas encore clairement définie. Les cellules Τ CD8 montrent un niveau d'expression plus élevé de ces molécules par rapport aux cellules Τ CD4. Ceci dépend de l'état des cellules. Parmi ces molécules, le CD160 est associé à l'incapacité des cellules à proliférer et à produire de l'IL-2, une protéine importante pour la prolifération et la survie cellulaire. L'incapacité des cellules exprimant le CD 160 à proliférer en réponse à des virus peut être restaurée par le blocage fonctionnel du récepteur CD 160.
Cette étude étoffe notre connaissance du rôle des cellules Τ CD8 ainsi que des conséquences induites par leur épuisement fonctionnel. Ces informations sont fondamentales pour le développement de nouvelles stratégies thérapeutiques et vaccinales
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