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Diazotrophs Show Signs of Restoration in Amazon Rain Forest Soils with Ecosystem Rehabilitation.
Biological nitrogen fixation can be an important source of nitrogen in tropical forests that serve as a major CO2 sink. Extensive deforestation of the Amazon is known to influence microbial communities and the biogeochemical cycles they mediate. However, it is unknown how diazotrophs (nitrogen-fixing microorganisms) respond to deforestation and subsequent ecosystem conversion to agriculture, as well as whether they can recover in secondary forests that are established after agriculture is abandoned. To address these knowledge gaps, we combined a spatially explicit sampling approach with high-throughput sequencing of nifH genes. The main objectives were to assess the functional distance decay relationship of the diazotrophic bacterial community in a tropical forest ecosystem and to quantify the roles of various factors that drive the observed changes in the diazotrophic community structure. We observed an increase in local diazotrophic diversity (α-diversity) with a decrease in community turnover (β-diversity), associated with a shift in diazotrophic community structure as a result of the forest-to-pasture conversion. Both diazotrophic community turnover and structure showed signs of recovery in secondary forests. Changes in the diazotrophic community were primarily driven by the change in land use rather than differences in geochemical characteristics or geographic distances. The diazotroph communities in secondary forests resembled those in primary forests, suggesting that at least partial recovery of diazotrophs is possible following agricultural abandonment.IMPORTANCE The Amazon region is a major tropical forest region that is being deforested at an alarming rate to create space for cattle ranching and agriculture. Diazotrophs (nitrogen-fixing microorganisms) play an important role in supplying soil N for plant growth in tropical forests. It is unknown how diazotrophs respond to deforestation and whether they can recover in secondary forests that establish after agriculture is abandoned. Using high-throughput sequencing of nifH genes, we characterized the response of diazotrophs' β-diversity and identified major drivers of changes in diazotrophs from forest-to-pasture and pasture-to-secondary-forest conversions. Studying the impact of land use change on diazotrophs is important for a better understanding of the impact of deforestation on tropical forest ecosystem functioning, and our results on the potential recovery of diazotrophs in secondary forests imply the possible restoration of ecosystem functions in secondary forests
Effect of cadmium on the morphology and anatomy of Salvinia auriculata
This study aimed to evaluate the morphological and anatomical changes of Salvinia auriculata exposed to different concentrations 0, 2.5, 5, 7.5 and 10 μM of cadmium (Cd) and its effect on plant growth. The experiment was conducted in the laboratory of Plant Anatomy of the IF Goiano/Rio Verde Campus, Goiás. Cd free samples of S. auriculata, was obtained from the Aquários Plantados company, located in Belo Horizonte. The material was grown hydroponically for 20 days and after the experimental period, the leaf samples were fixed, including in historesin, cut to 5 μm thick thick, stained with toluidine blue and the images were obtained in an optical microscope. The toxic effects of Cd on S. auriculata was observed at lowest concentration with the appearance of chlorotic and necrotic spots. Microscopic analysis showed increased height and width of the aerenchyma gaps, mesophyll and a reduction in abaxial surface epidermal cells, due to increased doses of this metal. It was observed that S. auriculata is a plant sensitive to Cd, and thus indicated for environmental monitoring.Key words: Ecological, aquatic species, pollution
The new automated daily mortality surveillance system
The experience reported in an earlier Eurosurveillance issue on a fast method to evaluate the impact of the 2003 heatwave on mortality in Portugal, generated a daily mortality surveillance system (VDM) that has been operating ever since jointly with the Portuguese Heat Health Watch Warning System. This work describes the VDM system and how it evolved to become an automated system operating year-round, and shows briefly its potential using mortality data from January 2006 to June 2009 collected by the system itself. The new system has important advantages such as: rapid information acquisition, completeness (the entire population is included), lightness (very little information is exchanged, date of death, age, sex, place of death registration). It allows rapid detection of impacts (within five days) and allows a quick preliminary quantification of impacts that usually took several years to be done. These characteristics make this system a powerful tool for public health action. The VDM system also represents an example of inter-institutional cooperation, bringing together organisations from two different ministries, Health and Justice, aiming at improving knowledge about the mortality in the population
Etiologic Evaluation and Investigation of Global Development Delay and Intellectual Disability
Developmental Delay (DD) and Intellectual Disability (ID), depending
on the affected individual being under or above five years-old, result
from environmental or genetic causes during the developmental period,
that manifest as a subnormal functioning of intellectual abilities. In
western countries there is a prevalence of about 3%, with a great impact
in the individuals, their families, as well as in the society. Etiologic
diagnosis remains unknown in about 65-80% of the cases. It is a clinically
heterogeneous condition as it can be sporadic or familiar, encompassing
an autosomal dominant, recessive or X-linked transmission.
Etiologic investigation emphasizes the importance of the clinical and
family history as well as the physical examination, with special care for
dysmorphologic evaluation.
The authors reviewed DD/ ID focusing not only on clinical diagnosis but
mostly on genetic causes and etiologic investigation. The protocol presented
is followed by the Medical Genetics Department of Coimbra’s
Paediatrics Hospital, in accordance to the international consensus
Anatomical and histochemical analysis of vegetative organs of Vernonia ferruginea Less. (Asteraceae)
Vernonia ferruginea Less. is a perennial shrub species, present in several regions of Brazil, especially in the savanna. It is popularly used as a phytotherapic. This fact justifies the need to anatomically characterize the plant for its accurate identification and to conduct histochemical studies with the aim of identifying the chemical nature of its cellular constituents. The species-specific data will contribute significantly to pharmaceutical quality control and also provide information about the sites of specific chemical compounds. Samples of V. ferruginea vegetative organs were collected and submitted to the usual plant anatomy and histochemical techniques. The leaves are anfihipoestomática with anomocytic stomata; have tector and glandular trichomes that store essential oils. The stem has collateral-type vascular bundles arranged in a eustele structure; it also has glandular and tector trichomes. The root has brachysclereids, endoderm with various chemical compounds and vascular bundles having axial elements and rays. Few differences were found in the structure of vegetative organs in relation to other species of the genus, confirming the importance of the details shown.Key words: Plant anatomy, assapeixe-branco, essential oils
Endovascular treatment versus medical care alone for ischaemic stroke: systematic review and meta-analysis
Objectives: To evaluate the efficacy and safety of endovascular treatment, particularly adjunctive intra-arterial mechanical thrombectomy, in patients with ischaemic stroke. / Design: Systematic review and meta-analysis. / Data sources: Medline, Embase, Cochrane Central Register of Controlled Trials, Web of Science, SciELO, LILACS, and clinical trial registries from inception to December 2015. Reference lists were crosschecked. / Eligibility criteria for selecting studies: Randomised controlled trials in adults aged 18 or more with ischaemic stroke comparing endovascular treatment, including thrombectomy, with medical care alone, including intravenous recombinant tissue plasminogen activator (rt-PA). Trial endpoints were functional outcome (modified Rankin scale scores of ≤2) and mortality at 90 days after onset of symptoms. No language or time restrictions applied. / Results: 10 randomised controlled trials (n=2925) were included. In pooled analysis endovascular treatment, including thrombectomy, was associated with a higher proportion of patients experiencing good (modified Rankin scale scores ≤2) and excellent (scores ≤1) outcomes 90 days after stroke, without differences in mortality or rates for symptomatic intracranial haemorrhage, compared with patients randomised to medical care alone, including intravenous rt-PA. Heterogeneity was high among studies. The more recent studies (seven randomised controlled trials, published or presented in 2015) proved better suited to evaluate the effect of adjunctive intra-arterial mechanical thrombectomy on its index disease owing to more accurate patient selection, intravenous rt-PA being administered at a higher rate and earlier, and the use of more efficient thrombectomy devices. In most of these studies, more than 86% of the patients were treated with stent retrievers, and rates of recanalisation were higher (>58%) than previously reported. Subgroup analysis of these seven studies yielded a risk ratio of 1.56 (95% confidence interval 1.38 to 1.75) for good functional outcomes and 0.86 (0.69 to 1.06) for mortality, without heterogeneity among the results of the studies. All trials were open label. Risk of bias was moderate across studies. The full results of two trials are yet to be published. / Conclusions: Moderate to high quality evidence suggests that compared with medical care alone in a selected group of patients endovascular thrombectomy as add-on to intravenous thrombolysis performed within six to eight hours after large vessel ischaemic stroke in the anterior circulation provides beneficial functional outcomes, without increased detrimental effects. / Systematic review registration: PROSPERO CRD42015019340
Síndrome de Churg-Strauss
A síndrome de Churg-Strauss é uma vasculite ANCA-associada de pequenos e médios vasos. As manifestações clínicas mais comuns
são eosinofilia marcada, asma, sinusite crónica, infiltrados pulmonares,
cardiomiopatia, queixas gastrointestinais e mononeurite multiplex. Os anticorpos Anti-MPO (anti-mieloperoxidade), pANCA
(com padrão de imunoflurescência perinuclear) encontram-se presentes em 38-59% dos casos. O envolvimento cardíaco é
uma importante causa de morbilidade e a principal causa de mortalidade no síndrome de Churg-Strauss. Histologicamente
caracteriza-se por uma vasculite necrotizante eosinofílica.
O tratamento é baseado na corticoterapia e em fármacos imunosupressores
(ciclofosfamida e azatioprina) sendo determinado de acordo com critérios de prognóstico. A remissão completa ocorre em cerca de 90% dos casos, sendo as recaídas frequentes (25% dos casos)
Synthesis of novel methyl 3-(Hetero)arylthieno[3,2-b]pyridine-2-carboxylates and antitumor activity evaluation: Studies in vitro and in ovo grafts of chick chorioallantoic membrane (cam) with a triple negative breast cancer cell line
A series of novel functionalized methyl 3-(hetero)arylthieno[3,2-b]pyridine-2-carboxylates 2a–2h were synthesized by C-C Pd-catalyzed Suzuki-Miyaura cross-coupling of methyl 3-bromothie-no[3,2-b]pyridine-2-carboxylate with (hetero)aryl pinacol boranes, trifluoro potassium boronate salts or boronic acids. Their antitumoral potential was evaluated in two triple negative breast cancer (TNBC) cell lines—MDA-MB-231 and MDA-MB-468, by sulforhodamine B assay. Their effects on the non-tumorigenic MCF-12A cells were also evaluated. The results demonstrated that three compounds caused growth inhibition in both TNBC cell lines, with little or no effect against the non-tumorigenic cells. The most promising compound was further studied concerning possible effects on cell viability (by trypan blue exclusion assay), cell proliferation (by bromodeoxyuridine assay) and cell cycle profile (by flow cytometry). The results demonstrated that the GI50 concentration of compound 2e (13 µM) caused a decreased in MDA-MB-231 cell number, which was correlated with a decreased in the % of proliferating cells. Moreover, this compound increased G0/G1 phase and decreased S phases, when compared to control cells (although was not statistic significant). Interestingly, compound 2e also reduced tumor size using an in ovo CAM (chick chorioallantoic membrane) model. This work highlights the potential antitumor effect of a novel methyl 3-arylthieno[3,2-b]pyridine-2-carboxylate derivative.This research was funded by Fundação para a Ciência e Tecnologia (FCT)—Portugal that financially supports CQUM (UID/QUI/686/2019), also financed by European Regional Development Fund (ERDF), COMPETE2020 and Portugal2020, the PTNMR network also supported by Portugal2020. C.P.R.X. is supported through the post-doc grant SFRH/BPD/122871/2016 and J.M.R. through the doctoral grant SFRH/BD/115844/2016, by FCT, ESF (European Social Fund) and HCOP (Human Capital Operational Programme)
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