ABSTRACT The aim of this study was to evaluate Leishmania vectors and investigate the environmental and climatic characteristics related to their transmission. This was a prospective ...eco-epidemiological study involving the systematic collection of sandflies and a canine serological survey in areas of municipality in Brazil. Blood samples from 1,752 dogs were examined to test for canine visceral leishmaniasis (VL). An entomological evaluation was carried out using 24 light traps in the peridomicile and intradomicile areas of 12 households for 12 months. Climate variables were analyzed using a simple Spearman correlation and a spatial analysis via the fuzzy logic method and K function. The prevalence rate of canine VL was 4.1% and 7.1% in the two areas that were studied, respectively. The entomological study resulted in the capture of 431 sandflies. Most (74%) of the specimens were captured in the peridomiciliary area, and 5.6% of the samples that were analyzed using molecular biology were positive for Leishmania spp. In particular, Leishmania infantum was found in 100% of the positive samples. The spatial analysis showed that one particular area presented a higher concentration of high-density overlapping points of Lutzomyia longipalpis and seropositive dog populations, indicating a higher risk of the concomitant occurrence of both events. The results show that a parasite-reservoir-vector interface is active in the studied areas.
RESUMO Objetivou-se avaliar a fauna vetorial e os aspectos ambientais e climáticos relacionados à transmissão das leishmanioses. Foi realizado um estudo eco-epidemiológico prospectivo de coleta sistemática de flebotomíneos e inquérito censitário sorológico canino em áreas de um município do Brasil. Para determinar a taxa de prevalência de LVC, foram examinadas amostras de sangue de 1752 cães. Na avaliação entomológica, foram instaladas 24 armadilhas luminosas em 12 residências distribuídas, instaladas no ambiente de peridomicílio e intradomicílio durante 12 meses. Para análise dos aspectos climáticos, utilizou-se a correlação simples de Spearman e para análise espacial foram utilizadas a Lógica Fuzzy e a Função K. A taxa de prevalência em cães foi de 4,1% e 7,1%. No estudo entomológico, foram capturados 431 flebotomíneos. A maior parte (74%) dos espécimes foi capturada no peridomicílio. Em relação à infecção natural, 5,6 % das amostras analisadas por biologia molecular apresentaram positividade à infecção por Leishmania spp.. Em 100% das amostras positivas, encontrou-se infecção por Leishmania infantum. Na análise espacial uma Área apresentou maior concentração de pontos de sobreposição de alta densidade de Lutzomyia longipalpis e cães sororreagentes, indicando maior risco na ocorrência concomitante dos dois eventos. Os resultados mostram que a interface parasito-reservatório-vetor está ativa nas áreas estudadas.
The aim of this study was to investigate the potential anti-inflammatory and anti-oxidant effects of gabapentin (GBP) in mice. The anti-inflammatory and anti-oxidant effects were evaluated using ...various mediators that induce paw edema, peritonitis model, myeloperoxidase (MPO) activity, proinflammatory cytokine levels, glutathione (GSH) consumption, and malondialdehyde (MDA) production in mice. Pretreatment of mice with GBP (1 mg/kg) significantly reduced carrageenan or dextran-induced paw edema (
P
< 0.05) when compared to vehicle group. Adding to this, GBP (1 mg/kg) significantly inhibited paw edema induced by histamine, serotonin, bradikinin, 48/80 compound, and prostaglandin E
2
. In the carrageenan-induced peritonitis model, GBP significantly decreased total and differential leukocyte counts and reduced the levels of MPO activity in the plantar tissue and IL-1β and TNF-α concentrations in the peritoneal exudate. The same dose of GBP also decreased the MDA concentration and increased the levels of GSH into the peritoneal fluid. In summary, our results demonstrated that GBP exhibited anti-inflammatory activity in mice by reducing the action of inflammatory mediators, neutrophil migration and proinflammatory cytokine levels, and anti-oxidant properties by decreasing the concentration of MDA and increasing the GSH content. These observations raise the possibility that GBP could be used to improve tissue resistance to damage during inflammatory conditions.
A common challenge in drug design pertains to finding chemical modifications to a ligand that increases its affinity to the target protein. An underutilized advance is the increase in structural ...biology throughput, which has progressed from an artisanal endeavor to a monthly throughput of hundreds of different ligands against a protein in modern synchrotrons. However, the missing piece is a framework that turns high-throughput crystallography data into predictive models for ligand design. Here, we designed a simple machine learning approach that predicts protein-ligand affinity from experimental structures of diverse ligands against a single protein paired with biochemical measurements. Our key insight is using physics-based energy descriptors to represent protein-ligand complexes and a learning-to-rank approach that infers the relevant differences between binding modes. We ran a high-throughput crystallography campaign against the SARS-CoV-2 main protease (M
), obtaining parallel measurements of over 200 protein-ligand complexes and their binding activities. This allows us to design one-step library syntheses which improved the potency of two distinct micromolar hits by over 10-fold, arriving at a noncovalent and nonpeptidomimetic inhibitor with 120 nM antiviral efficacy. Crucially, our approach successfully extends ligands to unexplored regions of the binding pocket, executing large and fruitful moves in chemical space with simple chemistry.
Previous studies have reported the effects of pequi oil (Caryocar brasiliense Cambess.) in cancer prevention and treatment. However, its biomedical applications are limited due to the hydrophobic ...nature of the oil. In this study, we used nanotechnology strategies to design and characterize a pequi oil-based nanoemulsion and evaluate its anticancer effects. Our data show that monodisperse (PdI 0.23) pequi oil nanoemulsions (123 nm – hydrodynamic diameter; −15 mV – zeta potential) were prepared successfully using lecithin as surfactant and had physicochemical stability when exposed to stress conditions (pH and serial dilution) or long-term (200 days) storage at different temperatures. Significant dose- and time-dependent antitumoral effects against breast cancer cells (4T1) were also observed (IC50 of 299.8 and 173.7 μg/mL after 24 and 48 h respectively, p < 0.001), along with lower cytotoxicity against non-tumoral cells (NIH/3T3) (IC50 of 442.7 and 380.3 μg/mL after 24 and 48 h respectively). In addition, we show that in our formulation, pequi oil has a dual role, behaving both as a structural component of the nanoemulsion and as a cytotoxic agent against breast cancer cells. Taken together, our results reveal pequi oil-based nanoemulsion as a promising nanosized platform to be used as an adjuvant tool for breast cancer treatments.
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•A monodisperse nanoemulsion based on pequi oil (PeNE) was successfully obtained.•PeNE was stable under stress conditions and long-term storage.•PeNE showed significant antitumoral effects against breast cancer cells (4T1).•PeNE was less cytotoxic against non-tumoral cells (NIH/3T3) than in 4T1 cells.
Biodiversity assessment is a mandatory task for sustainable and adaptive management for the next decade, and long-term ecological monitoring programs are a cornerstone for understanding changes in ...ecosystems. The Brazilian Long-Term Ecological Research Program (PELD) is an integrated effort model supported by public funds that finance ecological studies at 34 locations. By interviewing and compiling data from project coordinators, we assessed monitoring efforts, targeting biological groups and scientific production from nine PELD projects encompassing coastal lagoons to mesophotic reefs and oceanic islands. Reef environments and fish groups were the most often studied within the long-term projects. PELD projects covered priority areas for conservation but missed sensitive areas close to large cities, as well as underrepresenting ecosystems on the North and Northeast Brazilian coast. Long-term monitoring projects in marine and coastal environments in Brazil are recent (<5 years), not yet integrated as a network, but scientifically productive with considerable relevance for academic and human resources training. Scientific production increased exponentially with project age, despite interruption and shortage of funding during their history. From our diagnosis, we recommend some actions to fill in observed gaps, such as: enhancing projects' collaboration and integration; focusing on priority regions for new projects; broadening the scope of monitored variables; and, maintenance of funding for existing projects.
The present study analyzed blood pressure responses after a single session of isometric handgrip exercise performed with different volumes and intensities by patients with hypertension.
This ...randomized crossover trial submitted 12 hypertensive patients (58±5 years old) to four isometric handgrip exercise sessions in a random order: 4 x 2 min at 30% of the maximal voluntary contraction (S30%); 4 x 2 min at 50% of the maximal voluntary contraction (S50%2min); 4 x 3 min at 30% of the maximal voluntary contraction (S30%3min); and a control session. The systolic and diastolic blood pressure, heart rate, and rate-pressure product were measured pre- and post-exercise (30th min).
No significant changes were observed in cardiovascular variables after any session (p>0.05 for all comparisons). Similarly, individual analyses revealed heterogeneity in the responses, including increases in blood pressure observed in some sessions. Patients with reduced blood pressure after an isometric handgrip exercise session exhibited a higher body mass index, diastolic blood pressure and heart rate (p<0.05). They also tended to be younger (p=0.07).
Isometric handgrip exercise performed with different intensities and volumes did not reduce the blood pressure of hypertensive patients.
In this work, a hydrophilic clay, Na-montmorillonite from Wyoming, USA, was rendered organophilic by exchanging the inorganic interlayer cations for hexadecyltrimethylammonium ions (HDTA), with the ...formulae of (CH
3)
3N(C
16H
33)
+ ion. Based on fact that organo-clay has high affinities for non-ionic organic molecules, 1,3,4-thiadiazole-2,5-dithiol was loaded on the HDTA-montmorillonite surface, resulting in the 1,3,4-thiadiazole-2,5-dithiol-HDTA-montmorillonite complex (TDD-organo-clay).
The following properties of TDD-organo-clay are discussed: selective adsorption of heavy metal ions measured by batch and chromatographic column techniques, and utilization as preconcentration agent in a chemically modified carbon paste electrode (CMCPE) for determination of mercury(II).
The main point of this paper is the construction of a selective sensor, a carbon paste electrode modified with TDD-organo-clay, its properties and its application to the determination of mercury(II) ions, as this element belongs to the most toxic metals. The chemical selectivity of this functional group and the selectivity of voltammetry were combined for preconcentration and determination.
ABSTRACT Twelve dogs with traumatic hip luxation were selected for surgical intervention with a modified iliofemoral suture technique using an anchor screw to substitute the passage of suture ...material through a perforated tunnel in the ilium. Six procedures were performed with non-absorbable suture and other six with absorbable suture materials. These cases were evaluated at 15, 30, 60, and 90 days after surgery by performing an ambulation analysis and palpation of the joint. In all cases, there was a return of partial and total limb support in an average of 3 and 19 postoperative, respectively. The fixation strategy of the suture material in the ilium using an anchor screw proved to be efficient with a smaller surgical approach and lesser surgical difficulty, maintaining joint congruence in acute as chronic luxation cases. The use of absorbable and non-absorbable sutures had excellent clinical results, but there was a subjective superiority of the first ones, once 4 dogs of the non-absorbable group presented some discomfort during the postoperative palpation of the joint, 90 days after surgery.
RESUMO Doze cães com luxação coxofemoral traumática foram submetidos à intervenção cirúrgica de sutura iliofemoral modificada com uso de parafuso âncora substituindo a passagem de fio através de túnel perfurado no ílio. Seis procedimentos foram realizados com fio não absorvível, e outros seis com fio absorvível. Os casos foram avaliados aos 15, 30, 60 e 90 dias após a cirurgia, por meio de análise de deambulação e palpação articular. Em todos os casos, houve retorno de suporte parcial e total do peso no membro operado, em média, aos três e 19 dias de pós-operatório, respectivamente. A estratégia de fixação do fio de sutura no ílio com parafuso âncora se mostrou eficaz, permitindo uma abordagem cirúrgica menos invasiva, com menor dificuldade na execução, garantindo manutenção da congruência articular tanto em quadros de luxação aguda como crônica. O uso de fio absorvível e não absorvível teve bons resultados clínicos, porém houve uma superioridade subjetiva do primeiro, uma vez que quatro pacientes do grupo fio inabsorvível mostraram desconforto à palpação da articulação aos 90 dias após a cirurgia.
Capsicum species are frequently described in terms of genetic divergence, considering morphological, agronomic, and molecular databases. However, descriptions of genetic differences based on ...anatomical characters are rare. We examined the anatomy and the micromorphology of vegetative and reproductive organs of several Capsicum species. Four Capsicum accessions representing the species C. annuum var. annuum, C. baccatum var. pendulum, C. chinense, and C. frutescens were cultivated in a greenhouse; leaves, fruits and seeds were sampled and their organ structure analyzed by light and scanning electronic microscopy. Molecular accession characterization was made using ISSR markers. Polymorphism was observed among tector trichomes and also in fruit color and shape. High variability among accessions was detected by ISSR markers. Despite the species studied present a wide morphological and molecular variability that was not reflected by anatomical features.
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•Analysis of premature anchor rod failure in guyed transmission towers.•Deformations in steel microstructure were identified by EBSD analysis.•High chloride content found in the ...rust.•Increase of chloride and sulfate content in the soil adhered to corroded anchor rod.•Iron oxyhydroxide (FeOOH) formations were the key to premature anchor rod failure.
The mechanical rupture of buried structural components, such as the anchor rods of guyed transmission towers, poses a significant problem in electrical and mechanical engineering. In this work, joint evaluation of anchor rods microstructures, corrosion products, and environmental analysis of corroded anchor rods in a guyed tower was conducted. Microstructural metal analysis, electron microscopy scanning, and backscattered electron diffraction (type FEG-SEM/EBSD) were used to determine the disorientation of the crystalline structure (misorientation angle <5°) and elongated grains with sizes around 2–10 µm. Predominant crystallographic planes (001) and (111) were found to be more susceptible to corrosion than (101). Researchers also observed accumulations of chloride ions in concentrations of up to 10.2% in corrosion products, and in the soil surrounding the anchor rod, chloride and sulfate ions were found in concentrations of up to 5.15% and 2.33%, respectively.