Arthropods, the largest animal phylum, including insects, spiders and crustaceans, are characterized by their bodies being covered primarily in chitin. Besides being a source of this biopolymer, ...crustaceans have also attracted attention from biotechnology given their cuticles’ remarkable and diverse mechanical properties. The goose barnacle, Pollicipes pollicipes, is a sessile crustacean characterized by their body parts covered with calcified plates and a peduncle attached to a substrate covered with a cuticle. In this work, the composition and structure of these plates and cuticle were characterized. The morphology of the tergum plate revealed a compact homogeneous structure of calcium carbonate, a typical composition among marine invertebrate hard structures. The cuticle consisted of an outer zone covered with scales and an inner homogenous zone, predominantly organic, composed of successive layers parallel to the surface. The scales are similar to the tergum plate and are arranged in parallel and oriented semi-vertically. Structural and biochemical characterization confirmed a bulk composition of ɑ-chitin and suggested the presence of elastin-based proteins and collagen. The mechanical properties of the cuticle showed that the stiffness values are within the range of values described in elastomers and soft crustacean cuticles resulting from molting. The removal of calcified components exposed round holes, detailed the structure of the lamina, and changed the protein properties, increasing the rigidity of the material. This flexible cuticle, predominantly inorganic, can provide bioinspiration for developing biocompatible and mechanically suitable biomaterials for diverse applications, including in tissue engineering approaches.
The intensity and frequency of severe droughts in the Amazon region have increased in the recent decades. These extreme events are associated with changes in forest dynamics, biomass and floristic ...composition. However, most studies of drought response have focused on upland forests with deep water tables, which may be especially sensitive to drought. Palms, which tend to dominate the less well‐drained soils, have also been neglected. The relative neglect of shallow water tables and palms is a significant concern for our understanding of tropical drought impacts, especially as one‐third of Amazon forests grow on shallow water tables (<5 m deep).
We evaluated the drought response of palms and trees in forests distributed over a 600 km transect in central‐southern Amazonia, where the landscape is dominated by shallow water table forests (SWTF). We compared vegetation dynamics before and following the 2015–2016 El Nino drought, the hottest and driest on record for the region (−214 mm of cumulative water deficit).
We observed no change in stand mortality rates and no biomass loss in response to drought in these forests. Instead, we observed an increase in recruitment rates, which doubled to 6.78% year‐1 ± 4.40 (M ± SD) during 2015–2016 for palms and increased by half for trees (to 2.92% year‐1 ± 1.21), compared to rates in the pre‐El‐Nino interval. Within these SWTF, mortality and recruitment rates varied as a function of climatic drought intensity and water table depth for both palms and trees, with mortality being greatest in climatically and hydrologically wetter environments and recruitment greatest in drier environments. Across our transect, there was a significant increase over time in tree biomass.
Synthesis. Our results indicate that forests growing over shallow water tables—relatively under‐studied vegetation that nonetheless occupies one‐third of Amazon forests—are remarkably resistant to drought. These findings are consistent with the hypothesis that local hydrology and its interactions with climate strongly constrain forest drought effects, and has implications for climate change feedbacks. This work enhances our understanding of integrated drought effects on tropical forest dynamics and highlights the importance of incorporating neglected forest types into both the modelling of forest climate responses and into public decisions about priorities for conservation.
Our results indicate that forests growing over shallow water tables—relatively under‐studied vegetation that nonetheless occupies one‐third of Amazon forests—are remarkably resistant to drought. These findings are consistent with the hypothesis that local hydrology and its interactions with climate strongly constrain forest drought effects, and has implications for climate change feedbacks. This work enhances our understanding of integrated drought effects on tropical forest dynamics and highlights the importance of incorporating neglected forest types into both the modelling of forest climate responses and into public decisions about priorities for conservation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Background
Calcifying cyst odontogenic tumour (CCOT) is a rare benign cystic neoplasm of odontogenic origin. MMPs are responsible for extracellular matrix remodelling and, together their inhibitors ...and inducer, determinate the level of its turnover in pathological processes, leading to an auspicious microenvironment for tumour development. Thus, our goal was to evaluate matrix metalloproteinases (MMPs‐2, ‐7, ‐9 and ‐14), their inhibitors (TIMPs‐2, ‐3, ‐4 and RECK) and its inductor (EMMPRIN) expression in CCOT.
Materials and Methods
We used 18 cases of CCOT submitted to immunolocalization of the target proteins and analysed in both neoplastic odontogenic epithelial and stromal compartments.
Results
All molecules evaluated were expressed in both compartments in CCOT. In epithelial layer, immunostaining for MMPs, TIMPs, RECK and EMMPRIN was found in basal, suprabasal spindle and stellate cells surrounding ghost cells and ghost cells themselves, except for MMP‐9 and TIMP‐2 which were only expressed by ghost cells. In stromal compartment, extracellular matrix, mesenchymal (MC) and endothelial cells (EC) were positive for MMP‐2, ‐7, TIMP‐3 and ‐4, while MMP‐9, TIMP‐2 and RECK were positive only in MC and MMP‐14 only in EC. Statistical significance difference was found between both compartments for MMP‐9 (P < 0.001), RECK (P = 0.004) and EMMPRIN (P < 0.001), being more expressed in epithelium than in stroma. Positive correlation between both stromal EMMPRIN and RECK expression was found (R = 0.661, P = 0.003).
Conclusions
We concluded that these proteins/enzymes are differentially expressed in both epithelium and stroma of CCOT, suggesting an imbalance between MMPs and their inducer/inhibitors may contribute on the tumour behaviour.
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CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Resumo: Estima-se a mortalidade anual por acidentes de trabalho na agropecuária, 2000-2010, no Brasil. Empregou-se o Sistema de Informações sobre Mortalidade (SIM), para identificar os casos. Dados ...faltantes para ocupação e acidente de trabalho foram recuperados com informações individuais disponíveis, e incorporados casos ao total. Dados da população são dos Censos Demográficos. Foram identificados 8.923 óbitos por acidentes de trabalho, sendo 44,8% destes resultantes da recuperação. Em 2000, a mortalidade bruta por acidentes de trabalho foi estimada em 6,4/100 mil trabalhadores, aumentando para 8,1/100 mil em 2003, quando declinou para 7,3/100 mil em 2010. Entre os homens, "projeções de animais ou veículos de tração animal" foram as circunstâncias mais comuns, mas em mulheres foram as intoxicações por agrotóxicos. A mortalidade geral por acidentes de trabalho na agropecuária foi baixa quando comparada à de outros países, sugerindo sub-registro residual apesar da recuperação, o que requer melhoria da qualidade dos registros. Medidas de prevenção sensíveis a diferenças de gênero são necessárias.
Tetrahydrolinalool (THL) is an acyclic monoterpene alcohol, produced during linalol metabolism and also a constituent of essential oils. As described in the literature, many monoterpenes present ...anticonvulsant properties, and thus we became interested in evaluating the anticonvulsant activity of Tetrahydrolinalool using in mice model as well as in silico approaches. Our results demonstrated that THL increased latency to seizure onset and also reduced the mortality, in picrotoxin induced seizure tests. The results may be related to GABAergic regulation, which was also suggested in seizure testing induced by 3-mercapto-propionic acid. In the strychnine-induced seizure testing, none of the groups pretreated with THL modulated the parameters indicative of anticonvulsant effect. The electrophysiological results revealed that THL treatment reduces seizures induced by pentylenetetrazole. The in silico molecular docking studies showed that the interaction between THL and a GABAA receptor model formed a stable complex, in comparison to the crystaligraphic structure of diazepam, a structurally related ligand. In conclusion, all the evidences showed that THL presents effective anticonvulsant activity related to the GABAergic pathway, being a candidate for treatment of epileptic syndromes.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Este relato de caso possui o objetivo de relatar o tratamento da espasticidade de dois pacientes com o uso de fitocanabinoides. O caso 1 é de um paciente portador de hérnia discal cervical e lombar, ...evoluindo com espasticidade, principalmente em período noturno. Após o tratamento com fitocanabinoides, o paciente apresentou redução dos movimentos involuntários e redução dos despertares noturnos. O caso 2 é de uma paciente portadora de fibromialgia, associado a espasticidade de membros superiores, insônia e transtorno de humor. Após o tratamento com fitocanabinoides, a paciente evoluiu com cessação dos movimentos involuntários, melhora da qualidade de sono e melhora do quadro álgico. Conclui-se que os fitocanabinoides foram capazes de reduzir a espasticidade dos pacientes, e também auxiliou no tratamento de transtornos associados.
The engineering of core@multi-shell nanoparticles containing heterogeneous crystalline phases in different layers constitutes an important strategy for obtaining optical probes. The possibility of ...obtaining an opto-magnetic core@multi-shell nanoparticle capable of emitting in the visible and near-infrared ranges by upconversion and downshifting processes is highly desirable, especially when its optical responses are dependent on temperature and magnetic field variations. This work proposes the synthesis of hierarchically structured core@multi-shell nanoparticles of heterogeneous crystalline phases: a cubic core containing Dy
III
ions responsible for magnetic properties and optically active hexagonal shells, where Er
III
, Yb
III
, and Nd
III
ions were distributed. This system shows at least three excitation energies located at different biological windows, and its emission intensities are sensitive to temperature and external magnetic field variations. The selected crystalline phases of the core@multi-shell nanoparticles obtained in this work is fundamental to the development of multifunctional materials with potential applications as temperature and magnetic field optical probes.
Dual magnetic and temperature optical probes of hierarchically structured core@multi-shell nanoparticles with controlled crystalline phases: a magneto cubic core containing Dy
III
and a co-doped Er
III
:Yb
III
: Nd
III
optical hexagonal shell.
O potencial epidêmico do vírus Oropouche (OROV) demonstra a necessidade urgente de novos métodos de diagnóstico que possam ampliar os testes e fornecer resultados em menos tempo. A amplificação ...isotérmica mediada por transcrição reversa (RT-LAMP) é uma técnica molecular que possui alta especificidade, sensibilidade, rápida detecção e baixo custo, e está sendo amplamente utilizada no diagnóstico molecular. Portanto, o objetivo deste trabalho foi desenvolver e padronizar a técnica colorimétrica RT-LAMP para detecção do OROV. Reações de RT-LAMP foram realizadas utilizando o kit WarmStart LAMP colorimétrico 2x Master Mix, e o resultado foi determinado por avaliação visual através da mudança de cor do indicador de pH fenol vermelho. A concentração final dos reagentes, assim como a determinação da temperatura e tempo de reação otimizados. Um tempo máximo de reação de 25 minutos e a temperatura ideal de 67°C foram estabelecidos. O teste demonstrou alta sensibilidade em comparação com a RT-qPCR, sendo capaz de detectar cerca de uma cópia do vírus em poucos minutos e uma especificidade de 100% contra diversas arbovírus como Dengue, Zika, Chikungunya e Mayaro. A RT-LAMP para o vírus OROV é um diagnóstico inédito e de grande importância para auxiliar hospitais e centros de saúde ao redor do mundo no diagnóstico desse patógeno, que muitas vezes é confundido com outras arboviroses. Além disso, poderia ser uma ferramenta útil para vigilância epidemiológica do OROV, alertando a população sobre os possíveis riscos de surtos endêmicos desse vírus no país e auxiliando no controle desse patógeno negligenciado.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
O presente artigo tem como objetivo analisar o Programa Círculos de Leitura, realizado pela Secretaria da Educação do Estado do Ceará em parceria com o Instituto Fernand Braudel de Economia Mundial ...(IFBE), para a formação de leitoras(es) reflexivas(os) que busquem ampliar o acesso ao conhecimento literário. Para tanto, procuramos compreender como o projeto dialoga com o paradigma da formação de leitores e com as competências socioemocionais da Base Nacional Comum Curricular. Constatamos a presença de diversas competências da BNCC nos relatos utilizados como corpus de análise. Identificamos como tais competências são desenvolvidas mediante a prática da leitura durante os encontros dos Círculos, além de compreendermos como acontece a mediação dos participantes do Programa com o texto, estimulando a leitura e a subjetividade humana.
Left atrial (LA) volume indexing for body surface area (BSA) may underestimate LA size in obese and overweight people. Since LA volume is a risk marker for some cardiovascular events, it is suggested ...that indexing for height would be an alternative more appropriate method. The aims of this study were to find normal and the best cutoff values for LA volume indexed for height in our population.
Echocardiograms from 2018 to 2021 were reviewed and patients without known cardiac disease and completely normal echocardiograms that had the left atrial volume (LAvol) measured by biplane Simpson's method were included. LAvol was indexed by BSA (ml/m
), by height (LAvol/m), by height raised to exponent 2.7 (ml/ m
) and by height squared (ml/h
).
A total of 545 patients, 50.5 ± 13.4 y., 335 females (61,5%) were analyzed. There were 145 normal weight (26.6%), 215 overweight (39.4%), 154 obese (28.3%) and 31 low weight (5.7%) patients. To establish normal values we included only the normal weight group and considered normal values from 2SD below to 2SD above the mean. Mean and normal values were: LAvol/h 26.0 ±4.5, 17 - 35 ml/m, LAvol/ht
16 ± 2.8, 10.4 - 21.6 ml/ ht
and LAvol/ht
11.4 ± 2.2, 7.0 - 15.8 ml/m
. The normal LAvol/ht
differed between male and female (11.4 ± 2.4 and 12.8 ± 2.6, p < 0.001). LA diameter, LAvol, LAvol/h, LAvol/h
and LAvol/ht
increased progressively from low-weight, normal weight, overweight and obese patients (p< 0.0001), but not LAvol/BSA. When indexing LAvol for height, for height
and for height
20.8%, 22.7% and 21.4% of the obese patients, respectively, were reclassified as enlarged LA, and 7.4%, 8.8% and 8.4% of the overweight patients as well. Using ROC curve analysis, LAvol/h
had the highest AUC ant the best predictive value to identify LA enlargement and LAvol/BSA the worst one.
Normal values for LAvol indexed for height by three different methods are described in normal individuals. We reinforce that LAvol indexation for BSA underestimates LA size in obese and overweight patients and in these groups, specially, indexing for height
is probably the best method to evaluate LAvol.
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