447 research outputs found

    Activity and abundance of methane-oxidizing bacteria in secondary forest and manioc plantations of Amazonian Dark Earth and their adjacent soils

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    The oxidation of atmospheric CH4 in upland soils is mostly mediated by uncultivated groups of microorganisms that have been identified solely by molecular markers, such as the sequence of the pmoA gene encoding the ?-subunit of the particulate methane monooxygenase enzyme. The objective of this work was to compare the activity and diversity of methanotrophs in Amazonian Dark Earth soil (ADE, Hortic Anthrosol) and their adjacent non-anthropic soil. Secondly, the effect of land use in the form of manioc cultivation was examined by comparing secondary forest and plantation soils. CH4 oxidation potentials were measured and the structure of the methanotroph communities assessed by quantitative PCR (qPCR) and amplicon pyrosequencing of pmoA genes. The oxidation potentials at low CH4 concentrations (10 ppm of volume) were relatively high in all the secondary forest sites of both ADE and adjacent soils. CH4 oxidation by the ADE soil only recently converted to a manioc plantation was also relatively high. In contrast, both the adjacent soils used for manioc cultivation and the ADE soil with a long history of agriculture displayed lower CH4 uptake rates. Amplicon pyrosequencing of pmoA genes indicated that USC?, Methylocystis and the tropical upland soil cluster (TUSC) were the dominant groups depending on the site. By qPCR analysis it was found that USC? pmoA genes, which are believed to belong to atmospheric CH4 oxidizers, were more abundant in ADE than adjacent soil. USC? pmoA genes were abundant in both forested and cultivated ADE soil, but were below the qPCR detection limit in manioc plantations of adjacent soil. The results indicate that ADE soils can harbor high abundances of atmospheric CH4 oxidizers and are potential CH4 sinks, but as in other upland soils this activity can be inhibited by the conversion of forest to agricultural plantations

    Histochemical Evaluation of Human Prostatic Tissues with Cratylia mollis Seed Lectin

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    Lectins, proteins which selectively recognize carbohydrates, have been used in histochemistry for the evaluation of changes in glycosylation in processes of cellular differentiation and/or dedifferentiation. Cratylia mollis seed lectins (Cramoll 1,4 and Cramoll 3), conjugated to horseradish peroxidase, were used as histochemical probes in human prostate tissues: normal (NP), hyperplasia (BPH), and prostate carcinoma (PCa). The staining pattern of Con-A and Cramoll 1,4 in BPH was more intense than in NP. These lectins also showed staining differences between BPH and PCa; the latter showing decreased staining intensity with an increased degree of malignancy. PNA and Cramoll 3 stained epithelial cells similarly in all diagnoses although they did present intense staining of PCa glands lumen. Corpora amylacea were not differentially recognized by any of the lectins. Cramoll 1,4 and Cramoll 3 seed lectins present themselves as candidates for histochemical probes for prostate pathologies when compared to commercial lectins such as Con-A and PNA

    Epidemiology of COVID-19 in the State of Sergipe/Brazil and Its Relationship with Social Indicators

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    A pandemic is capable of generating a great impact, not only from the point of view of health, but also socioeconomically. In March 2020, the World Health Organization (WHO) declared that a new pandemic situation had arisen, due to the SARS-CoV-2 virus, whose probable origin was zoonotic. The largest number of cases of this disease is concentrated in the United States of America (USA), India, and Brazil. The mortality rate is estimated at 3.4%, but regional differences may exist, and places with a high demographic density have become true epicentres and may be related to higher rates of transmission. In addition to the above, lower human development indexes (HDI) can be related to worse outcomes, especially in the North and Northeast regions of Brazil since they are the least developed places. The Northeast region is the second-most-affected place in the number of COVID-19 cases in Brazil. An analytical observational study of an ecological type was carried out from April to October 2020 to assess the epidemiological situation of COVID-19 in the state of Sergipe and specifically to analyse the incidence of cases and deaths resulting from COVID-19 in the different health regions of the state of Sergipe, in relation to the values of the HDI and demographic density. During the study period, 84,325 cases of COVID-19 were identified, in which 2205 resulted in death. In most of the regions studied, there was a positive association between the number of cases and deaths and the greater the demographic density, but there was no increase in the risk of becoming ill, nor of dying the lower the HDI. Large and crowded cities are places of greatest vulnerability to illness, due to their greater capacity of transmitting the virus; however, further studies are needed to identify other factors that are decisive in the outcomes of this new disease.This research received no external funding.info:eu-repo/semantics/publishedVersio

    Calcaneal tendon plasticity following gastrocnemius muscle injury in rat

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    Cross-talk between skeletal muscle and tendon is important for tissue homeostasis. Whereas the skeletal muscle response to tendon injury has been well-studied, to the best of our knowledge the tendon response to skeletal muscle injury has been neglected. Thus, we investigated calcaneal tendon extracellular matrix (ECM) remodeling after gastrocnemius muscle injury using a rat model. Wistar rats were randomly divided into four groups: control group (C; animals that were not exposed to muscle injury) and harvested at different time points post gastrocnemius muscle injury (3, 14, and 28 days) for gene expression, morphological, and biomechanical analyses. At 3 days post injury, we observed mRNA-level dysregulation of signaling pathways associated with collagen I accompanied with disrupted biomechanical properties. At 14 days post injury, we found reduced collagen content histologically accompanied by invasion of blood vessels into the tendon proper and an abundance of peritendinous sheath cells. Finally, at 28 days post injury, there were signs of recovery at the gene expression level including upregulation of transcription factors related to ECM synthesis, remodeling, and repair. At this time point, tendons also presented with increased peritendinous sheath cells, decreased adipose cells, higher Young’s modulus, and lower strain to failure compared to the uninjured controls and all post injury time points. In summary, we demonstrate that the calcaneal tendon undergoes extensive ECM remodeling in response to gastrocnemius muscle injury leading to altered functional properties in a rat model. Tendon plasticity in response to skeletal muscle injury merits further investigation to understand its physiological relevance and potential clinical implications

    Recurrent Pregnancy Loss: Investigations and Interventions

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    Recurrent pregnancy loss (RPL) affects 0.8–1.4% of couples, and this prevalence increases with aging. However, etiology is commonly unknown, and most therapies are not supported by strong evidence. There are many examinations that investigate causes of RPL: hormonal status, spermatozoa morphology and DNA fragmentation, immunologic status, uterine assessment, thrombophilia, and others. Recently different types of treatment have emerged, most lacking good evidence. As for example, we may mention the use of anticoagulants, aspirin, corticosteroids, progesterone, and antioxidants and psychological support. It is argued that some procedures such as preimplantation genetic testing for aneuploidy and intracytoplasmic morphologically selected sperm injection would impact on the outcomes and help RPL management. This chapter will discuss the current evidence concerning examinations and treatments that would improve the outcomes in patients with RPL, with recommended practice

    Produção de l-asparaginase extracelular por fungos amazônicos

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    O principal agente terapêutico de doenças hematopoiéticas como a Leucemia Linfoide Aguda (LLA) consiste na aplicação de um biofármaco antileucêmico cujo mecanismo de ação atua na destruição de substâncias indispensáveis ao metabolismo das células tumorais. A L-Asparaginase é uma enzima que opera como agente antineoplásico diminuindo a concentração de asparagina livre no sangue, um aminoácido importante para a sobrevivência de células cancerígenas. A literatura relata que enzimas produzidas por bactérias apresentam reações adversas significativas aos humanos. Nessa direção, a L-Asparaginase de origem fúngica tem mostrado grande potencial no tratamento de LLA, apresentando características similares aquelas produzidas pelo organismo humano. O presente trabalho objetiva avaliar qualitativamente a produção de L-Asparaginase extracelular por fungos filamentosos da Amazônia. Para isso, foram selecionadas dez cepas de fungos filamentosos oriundos de solos e tubérculos amazônicos. O teste foi divido em duas etapas. A primeira etapa pré-fermentativa em meio Czapek Dox (pH 6,2) ideal no cultivo de microrganismos provenientes do solo, no qual permaneceram na incubadora Shaker por 96 horas a 30°C. Na segunda etapa, fermentativa, o micélio filtrado foi reinoculado em um novo meio Czapek Dox acrescido de 0,007% do indicador azul bromotimol, mantido sob agitação constante por 96 horas a 30° C. Os experimentos foram realizados em triplicata e a alteração na cor da solução inoculada para azul representa resultado positivo, visto que o indicador químico induz a mudança de cor à medida que o pH do meio aumenta, resultado da atividade enzimática do microrganismo (liberação da amônia pela hidrólise da L-asparagina). Das cepas fúngicas testadas para a produção extracelular de L-Asparaginase, seis obtiveram resultado positivo, apresentando coloração azul conforme o protocolo. E quatro apresentaram resultado negativo, com coloração não alterada. Por fim, os testes preliminares apontam para as constantes contribuições que a Amazônia oferece na síntese de enzimas para fabricação de biofármacos. Nesse sentido, fica evidente a grande importância em investir nas pesquisas direcionadas ao estudo sobre a capacidade dos fungos filamentosos da região em produzir substâncias de interesse biotecnológico. &nbsp
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