RESUMO
The Western Antarctic Peninsula (WAP) experiences one of the highest rates of sea surface warming globally, leading to potential changes in biological communities. Long-term phytoplankton monitoring in Potter Cove (PC, King George Island, South Shetlands) from the 1990s to 2009 revealed consistently low biomass values, and sporadic blooms dominated by cold-water microplankton diatoms. However, a significant change occurred between 2010 and 2020, marked by a notable increase in intense phytoplankton blooms in the region. During this period, the presence of a nanoplankton diatom, Shionodiscus gaarderae, was documented for the first time. In some instances, this species even dominated the blooms. S. gaarderae is recognized for producing blooms in temperate waters in both hemispheres. However, its blooming in the northern Southern Ocean may suggest either a recent introduction or a range shift associated with rising temperatures in the WAP, a phenomenon previously observed in experimental studies. The presence of S. gaarderae could be viewed as a warning sign of significant changes already underway in the northern WAP plankton communities. This includes the potential replacement of microplankton diatoms by smaller nanoplankton species. This study, based on observations along the past decade, and compared to the previous 20 years, could have far-reaching implications for the structure of the Antarctic food web.
Assuntos
Diatomáceas , Fitoplâncton , Regiões Antárticas , Plâncton , BiomassaRESUMO
Introduction: Intracellular communication is essential for the maintenance of the anterior pituitary gland plasticity. The aim of this study was to evaluate whether GPCR-Gαi modulates basic fibroblast growth factor (FGF2)-induced proliferative activity in normal pituitary cell populations. Methods: Anterior pituitary primary cell cultures from Wistar female rats were treated with FGF2 (10ng/mL) or somatostatin analog (SSTa, 100nM) alone or co-incubated with or without the inhibitors of GPCR-Gαi, pertussis toxin (PTX, 500nM), MEK inhibitor (U0126, 100µM) or PI3K inhibitor (LY 294002, 10 µM). Results: FGF2 increased and SSTa decreased the lactotroph and somatotroph BrdU uptak2e (p<0.05) whereas the FGF2-induced S-phase entry was prevented by SSTa co-incubation in both cell types, with these effects being reverted by PTX, U0126 or LY294002 pre-incubation. The inhibition of lactotroph and somatotroph mitosis was associated with a downregulation of c-Jun expression, a decrease of phosphorylated (p) ERK and pAKT. Furthermore, SSTa was observed to inhibit the S-phase entry induced by FGF2, resulting in a further increase in the number of cells in the G1 phase and a concomitant reduction in the number of cells in the S phases (p< 0.05), effects related to a decrease of cyclin D1 expression and an increase in the expression of the cell cycle inhibitors p27 and p21. Discussion: In summary, the GPCR-Gαi activated by SSTa blocked the pro-proliferative effect of FGF2 in normal pituitary cells via a MEK-dependent mechanism, which acts as a mediator of both anti and pro-mitogenic signals, that may regulate the principal effectors of the G1 to S-phase transition.
Assuntos
Fator 2 de Crescimento de Fibroblastos , Hipófise , Animais , Feminino , Ratos , Proliferação de Células , Fator 2 de Crescimento de Fibroblastos/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno , Fosfatidilinositol 3-Quinases/metabolismo , Ratos Wistar , Hipófise/citologia , Hipófise/efeitos dos fármacosRESUMO
Schistosoma mansoni infections, particularly egg antigens, induce Th2-dominant granulomatous responses accompanied by remarkable immunoregulatory mechanisms that avoid intense fibrosis. Interleukin (IL)-33 is a cytokine that stimulates the early activation of Th2 responses, and its soluble ST2 receptor (sST2) avoids granulomatous response, as well as CXCL9 and CXCL10 chemokines that have antifibrotic activity. However, in schistosomiasis, these molecules have not been suitably studied. Therefore, this study aimed to measure IL-33 and sST2 RNA, cytokines, and chemokines in peripheral blood cultures from individuals living in schistosomiasis-endemic areas. Peripheral blood cells from individuals with S. mansoni (n = 34) and non-infected individuals (n = 31) were cultured under mitogen stimulation. Supernatant chemokines and cytokines were evaluated using a cytometric bead array, and IL-33 and sST2 mRNA expression was measured using qPCR. Infected individuals showed higher levels of CXCL8, CXCL9, CXCL10, IFN-γ, TNF-α, IL-6, IL-2, IL-4, and IL-10; there was a lower expression of IL-33 mRNA and similar expression of sST2mRNA in infected than non-infected individuals. In conclusion, for the first time, we demonstrated lower IL-33mRNA expression and high levels of the antifibrotic chemokines CXCL9 and CXCL10 in schistosomiasis mansoni, which could control exacerbations of the disease in individuals from endemic areas.
Assuntos
Esquistossomose mansoni , Esquistossomose , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Interleucina-33/metabolismo , Leucócitos Mononucleares , RNA Mensageiro , Esquistossomose/metabolismo , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/metabolismoRESUMO
Studies point out that the development of social skills can interfere in the students' behavior and consequently in the environment, favoring the school climate and the acquisition of knowledge. Thus, this research aimed to identify the effects of a Social Skills Training (SST) on the school climate. 21 students from the 9th grade of Elementary School participated (11 from the Experimental group and 10 from the Control group) aged between 14 and 16 years old (MD = 14.38; SD = 1.07). The instruments used were: Inventory of Social Skills for Adolescents and the Climate Scale of the Delaware Student School. Ten sessions were held, with weekly meetings of 50 minutes. For data analysis, the following tests were used: Spearman's rô, Wilcoxon and Mann-Whitney for independent samples. There were positive correlations, from moderate to strong, between the factors of social skills and the dimensions of the climate for all participants in the intervention group. In the control group, negative and positive correlations were identified.
Estudos apontam que o desenvolvimento de habilidades sociais pode interferir no comportamento dos alunos e por consequência no ambiente, favorecendo o clima escolar e a aquisição do conhecimento. Dessa forma, esta pesquisa objetivou identificar os efeitos de um treinamento de habilidades sociais (THS) no clima escolar. Participaram 21 estudantes do nono ano do ensino fundamental (11 do grupo experimental e dez do grupo controle) com idades entre 14 e 16 anos (MD = 14,38; DP = 1,07). Os instrumentos utilizados foram: Inventário de Habilidades Sociais para Adolescentes e a Escala de Clima da Escola de Delaware-Estudante. Realizaram-se dez sessões, com encontros semanais de 50 minutos. Para análise de dados, utilizaram-se os testes rô de Spearman, Wilcoxon e Mann-Whitney para amostras independentes. Observaram-se correlações positivas de moderada a forte entre os fatores das habilidades sociais e as dimensões do clima para todos os participantes do grupo intervenção. No grupo controle, identificaram-se correlações negativas e positivas.
Los estúdios señalan que el desarrollo de habilidades sociales puede interferir em el comportamiento de los estudiantes y consecuentemente em el entorno, favoreciendo el clima escolar y la adquisición de conocimientos. Por lo tanto, esta investigación tuvo como objetivo identificar los efectos de un Entrenamiento de habilidades sociales (EHS) en el clima escolar. Participaron 21 alumnos de 9º de primaria (11 del grupo experimental y diez del grupo control) con edades comprendidas entre 14 y 16 años (DM = 14,38; DT = 1,07). Los instrumentos utilizados fueron: Inventario de Habilidades Sociales para Adolescentes y Escala de Clima de la Escuela de Delaware-Estudiantes. Se realizaron diez sesiones, con reuniones semanales de 50 minutos. Para el análisis de los datos se utilizaron las pruebas: rô de Spearman, Wilcoxon y Mann-Whitney para muestras independientes. Hubo correlaciones positivas de moderadas a fuertes entre los factores de habilidades sociales y las dimensiones del clima para todos los participantes en el grupo de intervención. Em el grupo de control se identificaron correlaciones negativas y positivas.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Instituições Acadêmicas , Estudantes , Comportamento , Habilidades Sociais , Personalidade , Psicologia Social , Ensino Fundamental e Médio , Escolaridade , Professores EscolaresRESUMO
Resumo Fundamento A nefropatia induzida por contraste (NIC) está associada a um risco aumentado de eventos cardiovasculares adversos maiores (ECAM), e a associação entre NIC e mecanismos oxidativos está bem documentada. Objetivo Este estudo visou avaliar a relação entre os níveis séricos da molécula de lesão renal-1 (KIM-1) e a NIC em pacientes idosos com infarto do miocárdio sem supradesnivelamento do segmento ST (IAMSSST). Métodos O presente estudo incluiu um total de 758 pacientes com IAMSSST que foram submetidos a intervenção coronária percutânea (ICP); 15 desenvolveram NIC após a ICP e outros 104 constituíram o grupo controle, pareado por idade > 65 anos. Foram registrados os valores laboratoriais desde a linha de base até o período entre 48 e 72 horas e os achados clínicos. Os pacientes foram acompanhados durante um ano. Foram considerados significativos valores de p < 0,05. Resultados A NIC foi observada em 12,60% dos pacientes. A KIM-1 sérica foi significativamente mais alta no grupo com NIC que no grupo sem NIC (14,02 [9,53 - 19,90] versus 5,41 [3,41 - 9,03], p < 0,001). O escore Mehran foi significativamente mais alto no grupo com NIC do que no grupo sem NIC (14 [5 - 22] versus 5 [2 - 7], p = 0,001). Os ECAM foram significativamente maiores no grupo com NIC do que no grupo sem NIC (7 [46,70%] versus 12 [11,50%], p = 0,001). A análise de regressão logística multivariada mostrou que o nível de KIM-1 basal (OR = 1,652, IC 95%: 1,20 - 2,27, p = 0,002) e o escore Mehran (OR = 1,457, IC 95%: 1,01 - 2,08, p = 0,039) foram preditores independentes da NIC em pacientes idosos com IAMSSST. Conclusão A concentração sérica basal de KIM-1 e o escore de Mehran são preditores independentes de NIC em pacientes idosos com IAMSSST. Além disso, todas as causas de mortalidade, morte cardiovascular, reinfarto do miocárdio, acidente vascular cerebral e MACE foram significativamente maiores no grupo CIN no acompanhamento de um ano. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)
Abstract Background Contrast-induced nephropathy (CIN) is associated with an increased risk of major adverse cardiovascular events (MACE), and the association between CIN and oxidative mechanisms is well documented. Objective This study aimed to evaluate the relationship between serum levels of kidney injury molecule-1 (KIM-1) and CIN in elderly patients with non-ST-segment elevation myocardial infarction (NSTEMI). Methods This study included a total of 758 patients with NSTEMI, who underwent percutaneous coronary intervention (PCI); 15 developed CIN after PCI, and another 104 were the control group, matched for age > 65 years. Baseline to 48-to-72-hour laboratory values and clinical outcomes were recorded. Patients were followed during one year. P values of < 0.05 were considered significant. Results CIN was observed in 12.60% of the patients. Serum KIM-1 was significantly higher in the CIN group than in the non-CIN group (14.02 [9.53 - 19.90] vs. 5.41 [3.41 - 9.03], p < 0.001). The Mehran score was significantly higher in the CIN group than in the non-CIN group (14 [5 - 22] vs. 5 [2 - 7], p = 0.001). MACE were significantly higher in the CIN group than in the non-CIN group (7 [46.70%] vs. 12 [11.50%], p = 0.001). Multivariate logistic regression analysis showed that baseline KIM-1 level (OR = 1.652, 95% CI: 1.20 - 2.27, p = 0.002) and Mehran score (OR = 1.457, 95% CI: 1.01 - 2.08, p = 0.039) were independent predictors of CIN in elderly patients with NSTEMI. Conclusion Baseline serum KIM-1 concentration and Mehran score are independent predictors of CIN in elderly patients with NSTEMI. Additionally, all-cause mortality, cardiovascular death, myocardial reinfarction, stroke, and MACE were significantly higher in the CIN group at one-year follow-up. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)
Assuntos
Humanos , Idoso , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Nefropatias , Fatores de Risco , Meios de Contraste , RimRESUMO
The isolation of single monoclonal antibodies (mAbs) against a given antigen was only possible with the introduction of the hybridoma technology, which is based on the fusion of specific B lymphocytes with myeloma cells. Since then, several mAbs were described for therapeutic, diagnostic, and research purposes. Despite being an old technique with low complexity, hybridoma-based strategies have limitations that include the low efficiency on B lymphocyte-myeloma cell fusion step, and the need to use experimental animals. In face of that, several methods have been developed to improve mAb generation, ranging from changes in hybridoma technique to the advent of completely new technologies, such as the antibody phage display and the single B cell antibody ones. In this review, we discuss the hybridoma technology along with emerging mAb isolation approaches, taking into account their advantages and limitations. Finally, we explore the usefulness of the hybridoma technology nowadays.
RESUMO
Overfishing is a concerning threat that can lead to the collapse of fish stocks. We assessed the combinations of factors, including biological traits, types of exploitation and responses to sea temperature and salinity changes, that drive species to collapse in the Brazilian Exclusive Economic Zone (EEZ) tropical and subtropical regions. We applied a catch-based method of stock classification and a catch time series of 61â¯years from 132 exploited fish species. Species were categorized as Collapsed, Overexploited, Fully Exploited or in Development, and we used a GAM analysis to understand their categorization over time. Furthermore, a Redundancy Analysis was developed to assess the species characteristics that best predicted each exploitation category. Twelve species were classified as Collapsed, 55 as Overexploited, 46 as Fully Exploited and 19 as in Development. Tropical and subtropical exploited species collapses in Brazil were best explained by a complex combination of a negative impact of warmer sea temperatures, fishery exploitation and specific life-history traits. A synergistic interaction between these factors could bring species to collapse. We hypothesize that the exploitation of species with vulnerable traits may alter how these species respond to temperature and, therefore, lead them to collapse given that intense exploitation may affect their ability to respond to temperature increases. Measures to mitigate climate change impacts should take into consideration incentives to decrease the exploitation of vulnerable species and, specifically, consider species with more sensitive biological traits. Such measures are also important to minimize the socioeconomic impacts on the people that depend on these species.
Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Brasil , Mudança Climática , Peixes , Alimentos Marinhos/estatística & dados numéricosRESUMO
The semi-arid region of Northeast Brazil (NEB) experiences severe droughts during El Niño Southern Oscillation (ENSO) years, with major impacts on the dynamics of the native vegetation (Caatinga). However, the effect of these droughts on carbon cycling is not well understood. Here, a numerical model is used to investigate the influence of variations in Pacific and Atlantic sea surface temperatures (SST) on drought and carbon dynamics of the Caatinga during past ENSO events. We demonstrate that precipitation reductions in the Caatinga have a strong influence on vegetation dynamics, with net primary production (NPP) remaining low throughout the droughts. Furthermore, the Caatinga acts as a carbon sink, even in years of severe drought. However, net ecosystem exchange (NEE) is lower in years of low NPP rates, resulting in long periods with limited ecosystem activity. The SST patterns indicate that extreme vegetation changes in the Caatinga are associated with the combination of ENSO events and North Atlantic SST warming.
Assuntos
El Niño Oscilação Sul , Florestas , Brasil , Oceano PacíficoRESUMO
The upwelling cores on the Caribbean Colombian coasts are mainly located at the Peninsula de la Guajira and Cabo de la Aguja. We used monthly averaged Moderate Resolution Imaging Spectroradiometer (MODIS) sea surface temperature as the only information to build up a prediction model for the upwelling events. This comprised two steps: (i) the reduction of the complexity by means of the Karhunen-Loève transform and (ii) a prediction model of time series. Two prediction models were considered: (a) a parametric autoregressive-moving average (ARMA) time series from the Box-Jenkins methodology and (b) a harmonic synthesis model. The harmonic synthesis also comprised of two steps: the maximum entropy spectral analysis and a least-squares harmonic analysis on the set of frequencies. The parametric ARMA time series model failed at the time of prediction with a very narrow range, and it was quite difficult to apply. The harmonic synthesis allowed prediction with a horizon of six months with a correlation of about 0.80. The results can be summarized using the time series of the weights of the different oscillation modes, their spatial structures with the nodal lines, and a high confidence model with a horizon of prediction of about four months.
RESUMO
Monthly data of abiotic variables (sea surface temperature; minimum and maximum air temperature; minimum, mean and maximum air humidity; minimum, mean and maximum atmospheric pressure; minimum, mean and maximum dew point; sea surface salinity; wind speed and direction; minimum and maximum tidal level and photosynthetically available radiation) were collected from different online repositories, all regarding the period between January 2013 and December 2017, from localities near Mar Casado Beach rocky shore, in São Paulo State southern coast, Brazil. Principal Component Analysis was performed to verify data variance and correlations among variables. Linear regression decomposition methods were applied to identify trend and seasonal patterns within the time indexed data. Deseasonalized time series were analyzed to identify structural breaks in trend patterns. Spectral analysis was applied to detrended time series.
RESUMO
The forest dynamics in the Amazonian floodplains is strongly triggered by the flood pulse. Trees respond to unfavorable growth conditions during the flood period by cambial dormancy, which results in the formation of annual growth rings. We determined tree age and compared the mean annual rates of increase in the diameter of Macrolobium acaciifolium with hydrological and climatic factors in three regions of central Amazonian floodplain forest. A wood sample was obtained from each tree using an increment borer. Ring growth was assessed by marginal parenchyma bands to determine tree age and the mean diameter increment. Ring widths were indexed to construct cross-dating chronologies and correlated with climatic and hydrological variables. The analyses demonstrate that the mean annual diameter increment did not differ between the three study sites. The chronologies correlated significantly with the terrestrial phase. There was no significant difference in the ring-width index between El Niño years and other years, and between La Niña and other years. These results show that the hydrological variables can be considered crucial to the rates of tree growth and diameter increment in floodplains, and El Niño signals were not detected in the tree-ring chronologies.
A dinâmica das florestas alagáveis da Amazônia é fortemente influenciada pelo pulso anual de inundação. As árvores respondem às condições de crescimento desfavoráveis durante o período de inundação através da dormência cambial, resultando na formação de anéis de crescimento anuais. Neste estudo, determinamos a idade das árvores e comparamos as taxas anuais médias de incremento em diâmetro de Macrolobium acaciifolium com fatores hidrológicos e climáticos em três regiões de florestas alagáveis na Amazônia central. Para cada árvore, uma amostra de madeira foi obtida usando uma broca dendrocronológica. O crescimento do anel foi avaliado por bandas de parênquima marginal, para determinar a idade da árvore e o incremento médio em diâmetro. As séries de anéis foram indexadas, para construir cronologias, e correlacionadas com variáveis climáticas e hidrológicas. Nossas análises demonstraram que o incremento anual médio em diâmetro não diferiu entre os três locais de estudo. As cronologias correlacionaram-se significativamente com a fase terrestre. Não houve diferença significativa no índice de largura dos anéis entre os anos de El Niño e outros anos, e entre os anos de La Niña e outros anos. Estes resultados mostraram que as variáveis hidrológicas podem ser consideradas cruciais para as taxas de crescimento e de incremento em diâmetro das árvores em florestas alagáveis, e que não foram detectados sinais de El Niño nas cronologias das árvores analisadas.
Assuntos
Ciclo Hidrológico , Efeitos do Clima/análise , Estágios do Ciclo de Vida , Fabaceae/crescimento & desenvolvimento , Fatores Abióticos/análise , Brasil , Ecossistema AmazônicoRESUMO
The forest dynamics in the Amazonian floodplains is strongly triggered by the flood pulse. Trees respond to unfavorable growth conditions during the flood period by cambial dormancy, which results in the formation of annual growth rings. We determined tree age and compared the mean annual rates of increase in the diameter of Macrolobium acaciifolium with hydrological and climatic factors in three regions of central Amazonian floodplain forest. A wood sample was obtained from each tree using an increment borer. Ring growth was assessed by marginal parenchyma bands to determine tree age and the mean diameter increment. Ring widths were indexed to construct cross-dating chronologies and correlated with climatic and hydrological variables. The analyses demonstrate that the mean annual diameter increment did not differ between the three study sites. The chronologies correlated significantly with the terrestrial phase. There was no significant difference in the ring-width index between El Niño years and other years, and between La Niña and other years. These results show that the hydrological variables can be considered crucial to the rates of tree growth and diameter increment in floodplains, and El Niño signals were not detected in the tree-ring chronologies.(AU)
A dinâmica das florestas alagáveis da Amazônia é fortemente influenciada pelo pulso anual de inundação. As árvores respondem às condições de crescimento desfavoráveis durante o período de inundação através da dormência cambial, resultando na formação de anéis de crescimento anuais. Neste estudo, determinamos a idade das árvores e comparamos as taxas anuais médias de incremento em diâmetro de Macrolobium acaciifolium com fatores hidrológicos e climáticos em três regiões de florestas alagáveis na Amazônia central. Para cada árvore, uma amostra de madeira foi obtida usando uma broca dendrocronológica. O crescimento do anel foi avaliado por bandas de parênquima marginal, para determinar a idade da árvore e o incremento médio em diâmetro. As séries de anéis foram indexadas, para construir cronologias, e correlacionadas com variáveis climáticas e hidrológicas. Nossas análises demonstraram que o incremento anual médio em diâmetro não diferiu entre os três locais de estudo. As cronologias correlacionaram-se significativamente com a fase terrestre. Não houve diferença significativa no índice de largura dos anéis entre os anos de El Niño e outros anos, e entre os anos de La Niña e outros anos. Estes resultados mostraram que as variáveis hidrológicas podem ser consideradas cruciais para as taxas de crescimento e de incremento em diâmetro das árvores em florestas alagáveis, e que não foram detectados sinais de El Niño nas cronologias das árvores analisadas.(AU)
Assuntos
Fabaceae/crescimento & desenvolvimento , Fatores Abióticos/análise , Estágios do Ciclo de Vida , Efeitos do Clima/análise , Ciclo Hidrológico , Ecossistema Amazônico , BrasilRESUMO
The somatotropic axis (SA) regulates numerous aspects of vertebrate physiology such as development, growth, and metabolism and has influence on several tissues including neural, immune, reproductive and gastric tract. Growth hormone (GH) is a key component of SA, it is synthesized and released mainly by pituitary somatotrophs, although now it is known that virtually all tissues can express GH, which, in addition to its well-described endocrine roles, also has autocrine/paracrine/intracrine actions. In the pituitary, GH expression is regulated by several hypothalamic neuropeptides including GHRH, PACAP, TRH and SST. GH, in turn, regulates IGF1 synthesis in several target tissues, adding complexity to the system since GH effects can be exerted either directly or mediated by IGF1. In reptiles, little is known about the SA components and their functional interactions. The aim of this work was to characterize the mRNAs of the principal SA components in the green iguana and to develop the tools that allow the study of the structural and functional evolution of this system in reptiles. By employing RT-PCR and RACE, the cDNAs encoding for GHRH, PACAP, TRH, SST and IGF1 were amplified and sequenced. Results showed that these cDNAs coded for the corresponding protein precursors of 154, 170, 243, 113, and 131 amino acids, respectively. Of these, GHRH, PACAP, SST and IGF1 precursors exhibited a high structural conservation with respect to its counterparts in other vertebrates. On the other hand, iguana's TRH precursor showed 7 functional copies of mature TRH (pyr-QHP-NH2), as compared to 4 and 6 copies of TRH in avian and mammalian proTRH sequences, respectively. It was found that in addition to its primary production site (brain for GHRH, PACAP, TRH and SST, and liver for IGF1), they were also expressed in other peripheral tissues, i.e. testes and ovaries expressed all the studied mRNAs, whereas TRH and IGF1 mRNAs were observed ubiquitously in all tissues considered. These results show that the main SA components in reptiles of the Squamata Order maintain a good structural conservation among vertebrate phylogeny, and suggest important physiological interactions (endocrine, autocrine and/or paracrine) between them due to their wide peripheral tissue expression.
Assuntos
Hormônio Liberador de Hormônio do Crescimento/genética , Iguanas/genética , Fator de Crescimento Insulin-Like I/genética , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Somatostatina/genética , Hormônio Liberador de Tireotropina/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Hormônio Liberador de Hormônio do Crescimento/química , Hormônio Liberador de Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/química , Fator de Crescimento Insulin-Like I/metabolismo , Filogenia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/química , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Somatostatina/química , Somatostatina/metabolismo , Hormônio Liberador de Tireotropina/química , Hormônio Liberador de Tireotropina/metabolismoRESUMO
Somatostatin is a peptide able to stop breathing, acting in the neural network that generates and control the respiratory rhythm. In this chapter, we present data on the early postnatal development of somatostatinergic systems in the mouse brainstem and summarize evidence for their influence on the generation and control of the respiratory rhythm.
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Tronco Encefálico/fisiologia , Neurônios/metabolismo , Respiração , Centro Respiratório/fisiologia , Somatostatina/metabolismo , Animais , Tronco Encefálico/crescimento & desenvolvimento , Tronco Encefálico/metabolismo , Camundongos , Centro Respiratório/crescimento & desenvolvimento , Centro Respiratório/metabolismoRESUMO
Resumo Este artigo é resultado de pesquisa de campo realizada junto aos coletores de sementes e frutos oleaginosos - Produtos Florestais Não Madeireiros (PFNMs) - em áreas rurais de Salvaterra e Bragança, no estado do Pará. O objetivo é contribuir com os estudos empíricos sobre saúde e segurança ocupacional no extrativismo, ainda incipientes no Brasil, por falta de amparo técnico-científico relacionado à atividade extrativista e por falta de regulamentação específica para a área. A pesquisa, realizada a partir da coleta de dados primários e observacionais, aponta os riscos de saúde e segurança aos quais os coletores estão expostos e os métodos de prevenção de acidentes, a fim de identificar possíveis melhorias nas condições de trabalho em um contexto onde a regulamentação de padrões trabalhistas para autônomos, informais e extrativistas na Amazônia é praticamente inexistente. A metodologia se caracteriza como estudo de caso em profundidade com coleta de dados primários com adoção de métodos mistos para sua sistematização. Os resultados demonstram que novas práticas e normas precisam ser adotadas para que os riscos à saúde e à segurança dos coletores sejam minimizados, além de garantir fiscalização, incentivo e monitoramento de práticas de segurança adequadas à atividade e específicas para cada região.
Abstract This article is the result of a field research conducted among collectors of oleaginous seeds and fruits - Non-Timber Forest Products (NTFP) - in the rural areas of Salvaterra and Bragança, in the state of Pará, Brazil. It aimed to contribute to empirical studies on health and occupational safety in extractivism, still incipient in Brazil due to the lack of technical-scientific support and the lack of specific regulation on the area. The research was conducted by the collection of primary and observational data that point out the risks to health and safety to which collectors are exposed to and the methods to prevent accidents in order to identify possible improvements to working conditions in a context in which labor regulation standards for autonomous, informal and extractive workers in the Amazon is practically inexistent. This paper's methodology is characterized as an embedded case study along with the collection of quantitative and qualitative data with the adoption of mixed methods for their systematization. The results show that new practices and norms should be adopted so the risks to health and safety of collectors are minimized, besides ensuring the inspection, incentives and monitoring of safety practices that are adequate to the activity and specific to each region.
Assuntos
Humanos , Masculino , Feminino , População Rural , Condições de Trabalho , Saúde Ocupacional , Agricultura Florestal , Riscos OcupacionaisRESUMO
The regulatory effect of allergic responses induced by IgG antibodies on human intra-thymic cells has not been reported in the literature. The aim of this study was to evaluate the possible differential effect of purified IgG from atopic and non-atopic individuals on human intra-thymic αßT cell cytokine production. Thymic tissues were obtained from 14 patients who were less than 7 d old. Additionally, blood samples were collected from atopic and non-atopic volunteers. Thymocytes and peripheral blood mononuclear cells were cultured with purified atopic or non-atopic IgG, and intracellular cytokine production was assessed. Purified IgG did not influence the frequency or viability of human intra-thymic αßT cells. Purified non-atopic IgG induced greater IFN-γ production by intra-thymic CD4+CD8+ T cells than did the mock treatment and atopic IgG. A similar effect of purified non-atopic IgG on TCD8 cells was observed compared with the mock treatment. Atopic IgG inhibited IFN-γ and TGF-ß production by intra-thymic TCD4 cells. Treatment with intravenous immunoglobulin resulted in intermediate levels of IFN-γ and TGF-ß in intra-thymic TCD4 cells compared with treatment with atopic and non-atopic IgG. Peripheral TCD4 cells from non-atopic individuals produced IFN-γ only in response to atopic IgG. This report describes novel evidence revealing that IgG from atopic individuals may influence intracellular IFN-γ production by intra-thymic αßT cells in a manner that may favor allergy development.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Hipersensibilidade Imediata , Imunoglobulinas Intravenosas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Interferon gama/metabolismo , Timócitos/imunologia , Técnicas de Cocultura , Humanos , Recém-Nascido , Timo/imunologiaRESUMO
BACKGROUND: Chronic schistosomiasis and its severe complication, periportal fibrosis, are characterized by a predominant Th2 response. To date, specific single nucleotide polymorphisms in ST2 have been some of the most consistently associated genetic variants for asthma. OBJECTIVE: We investigated the role of ST2 (a receptor for the Th2 cytokine IL-33) in chronic and late-stage schistosomiasis caused by Schistosoma japonicum and the potential effect of ST2 genetic variants on stage of disease and ST2 expression. METHODS: We recruited 947 adult participants (339 with end-stage schistosomiasis and liver cirrhosis, 307 with chronic infections without liver fibrosis, and 301 health controls) from a S japonicum-endemic area (Hubei, China). Six ST2 single nucleotide polymorphisms were genotyped. Serum soluble ST2 (sST2) was measured by ELISA, and ST2 expression in normal liver tissues, Hepatitis B virus-induced fibrotic liver tissues, and S japonicum-induced fibrotic liver tissues was measured by immunohistochemistry. RESULTS: We found sST2 levels were significantly higher in the end-stage group (36.04 [95% CI, 33.85-38.37]) compared with chronic cases and controls (22.7 [95% CI, 22.0-23.4], P < 1E-10). In addition, S japonicum-induced fibrotic liver tissues showed increased ST2 staining compared with normal liver tissues (P = .0001). Markers rs12712135, rs1420101, and rs6543119 were strongly associated with sST2 levels (P = 2E-10, 5E-05, and 6E-05, respectively), and these results were replicated in an independent cohort from Brazil living in a S mansoni endemic region. CONCLUSIONS: We demonstrate for the first time that end-stage schistosomiasis is associated with elevated sST2 levels and show that ST2 genetic variants are associated with sST2 levels in patients with schistosomiasis.
Assuntos
Doenças Endêmicas , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Cirrose Hepática/genética , Fígado/patologia , Schistosoma japonicum/imunologia , Schistosoma mansoni/imunologia , Esquistossomose/genética , Adulto , Animais , Brasil/epidemiologia , China/epidemiologia , Doença Crônica , Estudos de Coortes , Progressão da Doença , Feminino , Fibrose , Genótipo , Humanos , Proteína 1 Semelhante a Receptor de Interleucina-1/sangue , Interleucina-33/metabolismo , Fígado/parasitologia , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Esquistossomose/complicações , Esquistossomose/epidemiologiaRESUMO
Global warming is seen as one of the greatest threats to the world's coral reefs and, with the continued rise in sea surface temperature predicted into the future, there is a great need for further understanding of how to prevent and address the damaging impacts. This is particularly so for countries whose economies depend heavily on healthy reefs, such as those of the eastern Caribbean. Here, we compare the severity of bleaching and mortality for five dominant coral species at six representative reef sites in Barbados during the two most significant warm-water events ever recorded in the eastern Caribbean, i.e., 2005 and 2010, and describe prevailing island-scale sea water conditions during both events. In so doing, we demonstrate that coral bleaching and subsequent mortality were considerably lower in 2010 than in 2005 for all species, irrespective of site, even though the anomalously warm water temperature profiles were very similar between years. We also show that during the 2010 event, Barbados was engulfed by a transient dark green turbid water mass of riverine origin coming from South America. We suggest that reduced exposure to high solar radiation associated with this transient water mass was the primary contributing factor to the lower bleaching and mortality observed in all corals. We conclude that monitoring these episodic mesoscale oceanographic features might improve risk assessments of southeastern Caribbean reefs to warm-water events in the future.
RESUMO
Parallel studies of nesting colonies in Mexico and the United States show that Elegant Terns (Thalasseus elegans) have expanded from the Gulf of California Midriff Island Region into Southern California, but the expansion fluctuates from year to year. A strong inverse relationship between nesting pairs in three Southern California nesting areas [San Diego saltworks, Bolsa Chica Ecological Reserve, and Los Angeles Harbor (1991 to 2014)] and Isla Rasa in the Midriff (1980 to 2014) shows that terns migrate northward when confronting warm oceanographic anomalies (>1.0°C), which may decrease fish availability and hamper nesting success. Migration pulses are triggered by sea surface temperature anomalies localized in the Midriff and, secondarily, by reductions in the sardine population as a result of intensive fishing. This behavior is new; before year 2000, the terns stayed in the Midriff even when oceanographic conditions were adverse. Our results show that terns are responding dynamically to rapidly changing oceanographic conditions and fish availability by migrating 600 km northwest in search of more productive waters.