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1.
Braz J Biol ; 84: e280884, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38922194

RESUMO

Many anuran amphibians deposit their eggs in foam nests, biostructures that help protect the eggs and tadpoles from predators. Currently, there are no other identification and description studies of the cultivable microbiota role in the nests of the Leptodactylid frogs such as Physalaemus cuvieri, Leptodactylus vastus and Adenomera hylaedactyla. This study aimed to isolate and identify the culturable bacteria from these three anuran species' nests, as well as to prospect enzymes produced by this microbiota. Foam nests samples and environmental samples were diluted and viable cell count was determined. Bacterial morphotypes from foam nest samples were isolated through spread plate technique. Isolates' DNAs were extracted followed by rRNA 16S gene amplification and Sanger sequencing. To evaluate their enzymatic potential, the isolates were cultured in ATGE medium supplemented with starch (0.1% w/v), gelatin (3% w/v) and skimmed milk (1% w/v), to verify amylase and protease activity. A total of 183 bacterial morphotypes were isolated, comprising 33 bacterial genera. Proteobacteria phylum was the most abundant in all the three nests (79%). The genera Pseudomonas and Aeromonas were the most abundant taxon in P. cuvieri and L. vastus. In A. Hylaedactyla, were Enterobacter and Bacillus. Regarding enzymatic activities, 130 isolates displayed protease activity and 45 isolates were positive for amylase activity. Our results provide unprecedented information concerning culturable bacterial microbiota of the foam nests of the Leptodactylid frogs, as well as their potential for biomolecules of biotechnological interest.


Assuntos
Anuros , Bactérias , Animais , Anuros/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Comportamento de Nidação/fisiologia , Microbiota , DNA Bacteriano/análise
2.
Drug Chem Toxicol ; : 1-12, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38859707

RESUMO

The herbicide triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) is already considered an environmental problem due to damage caused by incorrect disposal, leaching, and aerial dispersion, which may pose risks to the environment and human health. Studies have evaluated metabolism, absorption, excretion, and active transport but there is no clear information about its mode of action (MoA) and its cytotoxic action potential remains unknown. In this context, mitochondria have been used to assess the toxicity of xenobiotics, for this reason, to identify the toxic mechanism of triclopyr, hepatic mitochondria from Wistar rats were exposed in vitro to different concentrations of triclopyr (0.5-500 µM). There was neither formation/accumulation of reactive oxygen and nitrogen species, nor lipid peroxidation or changes in the mitochondrial antioxidant system, in addition to proper functioning of oxidative phosphorylation and ATP production. Changes were found in NAD(P)H oxidation, membrane potential dissipation and mitochondrial calcium gradient. These results demonstrate that mitochondria suffer damage related to their bioenergetics and redox status but not to their structure when exposed to concentrations of triclopyr considered higher than those described as found in the environment so far.HighlightsTriclopyr has a low mitochondrial uncoupling potential.The damage caused to the bioenergetics and redox state of the mitochondria is related to concentrations considered higher than those found in the environment.Even at high concentrations, triclopyr was not able to change the structure of the organelle after exposure.Oxidative phosphorylation and ATP production were not impaired after exposure.NAD(P)H oxidation resulted in potential membrane dissipation and mitochondrial calcium gradient dissipation.Triclopyr does not have RONS-forming properties, as well as it does not peroxide membrane lipids, it preserves membrane sulfhydryl groups and maintains the normality of the GSH/GSSG ratio.

3.
Braz J Microbiol ; 55(1): 75-86, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38049661

RESUMO

Influenza affects approximately 10% of the world's population annually. It is associated with high morbidity and mortality rates due to its propensity to progress to severe acute respiratory infection, leading to 10-40% of hospitalized patients needing intensive care. Characterizing the multifactorial predictors of poor prognosis is essential for developing strategies against this disease. This study aimed to identify predictors of disease severity in influenza A-infected (IFA-infected) patients and to propose a prognostic score. A retrospective cross-sectional study was conducted with 142 IFA-infected out- and inpatients treated at a tertiary hospital between 2010 and 2018. The viral subtypes, hemagglutinin mutations, viral load, IL-28B SNPs, and clinical risk factors were evaluated according to the patient's ICU admission. Multivariate analysis identified the following risk factors for disease severity: neuromuscular diseases (OR = 7.02; 95% CI = 1.18-41.75; p = 0.032), cardiovascular diseases (OR = 5.47; 95% CI = 1.96-15.27; p = 0.001), subtype (H1N1) pdm09 infection (OR = 2.29; 95% CI = 1.02-5.15; p = 0.046), and viral load (OR = 1.43; 95% CI = 1.09-1.88; p = 0.009). The prognosis score for ICU admission is based on these predictors of severity presented and ROC curve AUC = 0.812 (p < 0.0001). Our results identified viral and host predictors of disease severity in IFA-infected patients, yielding a prognostic score that had a high performance in predicting the IFA patients' ICU admission and better results than a viral load value alone. However, its implementation in health services needs to be validated in a broader population.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Influenza Humana/complicações , Influenza Humana/epidemiologia , Estudos Retrospectivos , Vírus da Influenza A Subtipo H1N1/genética , Estudos Transversais , Gravidade do Paciente , Unidades de Terapia Intensiva
4.
J Helminthol ; 97: e104, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38148677

RESUMO

A new species of Oswaldocruzia Travassos, 1917 (Nematoda, Molineidae), parasite of Leptodactylus macrosternum Miranda-Ribeiro, 1926 (Anura: Leptodactylidae), from Caatinga morphoclimatic domain, Brazil, is described based on morphological and molecular data. Oswaldocruzia franciscoensis n. sp. is characterised by an anterior extremity with a cephalic vesicle divided into two portions, a body covered by cuticular longitudinal ridges, and cervical alae. Males of the new species have caudal bursa of type I with a 2-1-2 pattern, spicules divided into a shoe, bifurcated fork, and blade with two unequal branches, in which the longer branch bifurcates at its distal portion end and the smaller branch with three distal processes, each with distal bifurcations. Females have didelphic and amphidelphic uteri, an ovijector divided into vestibule, anterior and posterior sphincters, and anterior and posterior infundibula. The new species differs from its Neotropical congeners that have caudal bursa of type I, based on the presence of cervical alae and by having a spicular blade distally divided into two unequal branches, with the longer branch bifurcating at its distal portion and smaller branch with three distal processes, each distally bifurcated. The partial 18S rDNA sequence generated for Oswaldocruzia franciscoensis n. sp. is the first of a representative belonging to this genus in the Neotropical region.


Assuntos
Molineoidae , Nematoides , Trichostrongyloidea , Masculino , Feminino , Animais , Anuros/parasitologia , Brasil , Nematoides/genética
5.
Phys Chem Chem Phys ; 25(42): 28703-28715, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37849351

RESUMO

Extracting reliable information on certain physical properties of materials, such as thermal transport, can be computationally very demanding. Aiming to overcome such difficulties in the particular case of lattice thermal conductivity (LTC) of 2D nanomaterials, we propose a simple, fast, and accurate semi-empirical approach for LTC calculation. The approach is based on parameterized thermochemical equations and Arrhenius-like fitting procedures, thus avoiding molecular dynamics or ab initio protocols, which frequently require computationally expensive simulations. As a proof of concept, we obtain the LTC of some prototypical physical systems, such as graphene (and other 2D carbon allotropes), hexagonal boron nitride (hBN), silicene, germanene, binary, and ternary BNC lattices and two examples of the fullerene network family. Our obtained values are in good agreement with other theoretical and experimental estimations, nonetheless, being derived in a rather straightforward way, at a fraction of the usual computational cost.

6.
Arq. bras. med. vet. zootec. (Online) ; 75(5): 914-920, Sept.-Oct. 2023. graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1513653

RESUMO

ABSTRACT Chondrosarcoma, an unusual malignant neoplasm, develops in cartilaginous tissue and presents low rate of metastasis, mainly affecting the axial skeleton from the adult to senile dogs. In the face of unusual occurrence of chondrosarcoma in the long bones of young dogs, the present report aimed to describe it in the right humerus of a two-and-a-half-year-old Siberian Husky, attended at the Veterinary Hospital of the University of Franca, with limping of the right thoracic limb, for 20 days. The radiographic examination of the humerus showed bone lysis and periosteal proliferation. In the incisional biopsy, proliferation of atypical chondrocytes with diffuse distribution, interspersed with compact bone matrix, was observed. The amputation of the limb was performed, and the fragment histopathological analysis showed grade I chondrosarcoma. Periodic returns were made for neoplastic staging, and at 240 days after surgery lung metastases were detected, however, the tutor did not authorize chemotherapy and radiotherapy for financial reasons and due to the absence of respiratory symptoms so far (410 days after surgery). Although uncommon, chondrosarcoma can affect the long bones of young dogs, with clinical signs similar to other bone neoplasms, and, even with the radical limb amputation, can demonstrate systemic metastasis.


RESUMO O condrossarcoma, neoplasia maligna incomum, desenvolve-se em tecido cartilaginoso e apresenta baixo índice de metástases, acometendo principalmente o esqueleto axial de cães adultos a senis. Diante da ocorrência incomum de condrossarcoma em ossos longos de cães jovens, o presente relato teve como objetivo descrevê-lo no úmero direito de um Husky Siberiano de dois anos e meio de idade, atendido no Hospital Veterinário da Universidade de Franca, com claudicação do membro torácico direito, há 20 dias. O exame radiográfico do úmero mostrou lise óssea e proliferação periosteal. Na biópsia incisional, observou-se proliferação de condrócitos atípicos com distribuição difusa, intercalados com matriz óssea compacta. Foi realizada a amputação do membro, e a análise histopatológica do fragmento evidenciou condrossarcoma grau I. Foram feitos retornos periódicos para estadiamento neoplásico e, aos 240 dias após a cirurgia, foram detectadas metástases pulmonares. O tutor não autorizou quimioterapia e radioterapia por motivos financeiros e por ausência de sintomas respiratórios até o momento (410 dias após a cirurgia). Apesar de incomum, o condrossarcoma pode acometer os ossos longos de cães jovens, com sinais clínicos semelhantes a outras neoplasias ósseas, e, mesmo com a amputação radical do membro, pode demonstrar metástase sistêmica.

7.
J Mech Behav Biomed Mater ; 144: 105993, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37385128

RESUMO

Hydroxyapatite (HA) from bovine bones has been used as a biomaterial in dentistry due to its biocompatibility and bioactivity. However, dense HA bioceramics still present inadequate properties for applications that require high mechanical performance, such as infrastructure. Microstructural reinforcements and control of ceramic processing steps are methods to improve these shortcomings. The present study assessed the effects of polyvinyl butyral (PVB) addition in combination with two sintering methodologies (2-step and conventional), on the mechanical properties of polycrystalline bovine HA bioceramics. The samples were divided into four groups (with 15 samples per group): conventional sintering with binder (HBC) and without binder (HWC) and 2-step sintering with (HB2) and without binder (HW2). HA was extracted from bovine bones, turned into nanoparticles in a ball mill, and subjected to uniaxial and isostatic pressing into discs, according to ISO 6872 standards. All groups were characterized by x-ray diffractometry (XRD), differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and relative density. Besides, mechanical analyses (biaxial flexural strength (BFS) and modulus of elasticity) were also performed. The characterization results demonstrated that adding agglutinants or the sintering method did not affect HA's chemical and structural characteristics. Even so, the HWC group showed the highest mechanical values for BFS and modulus of elasticity being 109.0 (98.0; 117.0) MPa and 105.17 ± 14.65 GPa, respectively. The HA ceramics submitted to conventional sintering and without the addition of binders achieved better mechanical properties than the other groups. The impacts of each variable were discussed and correlated to the final microstructures and mechanical properties.


Assuntos
Durapatita , Nanopartículas , Animais , Bovinos , Durapatita/química , Materiais Biocompatíveis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cerâmica/química , Propriedades de Superfície , Teste de Materiais
8.
Sci Rep ; 13(1): 7460, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156829

RESUMO

Here, we study the problem of decoding information transmitted through unknown quantum states. We assume that Alice encodes an alphabet into a set of orthogonal quantum states, which are then transmitted to Bob. However, the quantum channel that mediates the transmission maps the orthogonal states into non-orthogonal states, possibly mixed. If an accurate model of the channel is unavailable, then the states received by Bob are unknown. In order to decode the transmitted information we propose to train a measurement device to achieve the smallest possible error in the discrimination process. This is achieved by supplementing the quantum channel with a classical one, which allows the transmission of information required for the training, and resorting to a noise-tolerant optimization algorithm. We demonstrate the training method in the case of minimum-error discrimination strategy and show that it achieves error probabilities very close to the optimal one. In particular, in the case of two unknown pure states, our proposal approaches the Helstrom bound. A similar result holds for a larger number of states in higher dimensions. We also show that a reduction of the search space, which is used in the training process, leads to a considerable reduction in the required resources. Finally, we apply our proposal to the case of the phase flip channel reaching an accurate value of the optimal error probability.

9.
Arq. bras. med. vet. zootec. (Online) ; 75(3): 511-518, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1436952

RESUMO

The aim of this study was to evaluate the effect of exogenous amylase on gas production, in vitro dry matter digestibility (IVDMD), and in vitro digestion kinetics of sorghum (Sorghum vulgaris) and two corn hybrids of different grain textures. Ruminal fluid was collected from two rumen-fistulated cows receiving or not exogenous amylase (0.7g kg-1 of dry matter (DM basis)), provided to achieve 396 kilo Novo units kg-1 for amylase activity (DM basis). Gas production was measured after 1, 3, 6, 9, 12, 15, 18, 21, 24, 30, 36, 42 e 48 hours of incubation. Amylase increased gas production (mL) by 5.4%. Corn hybrids have higher in vitro dry matter digestibility than sorghum. Exogenous amylase increased the potential of gas production (A) (P=0.01). There was an effect of hybrid for IVDMD (P<0.01). The addition of exogenous amylase increases the in vitro gas production, improves fermentation kinetics, and increases the production of the ammonia nitrogen of corn and sorghum grains, but does not affect in vitro and dry matter digestibility or the short-chain fatty acids production.


O objetivo deste estudo foi avaliar o efeito da amilase exógena na produção de gases, a digestibilidade in vitro da matéria seca (DIVMS) e a cinética de digestão in vitro de sorgo (Sorghum vulgaris) e de dois híbridos de milho de diferentes texturas de grãos. O líquido ruminal foi coletado de duas vacas fistuladas no rúmen recebendo ou não amilase exógena (0,7g kg-1 de matéria seca (MS)), fornecida para atingir 396 kg Novo unidades kg-1 para atividade de amilase (base na MS). A produção de gás foi medida após uma, três, seis, nove, 12, 15, 18, 21, 24, 30, 36, 42 e 48 horas de incubação. A amilase aumentou a produção de gás (mL) em 5,4%. Híbridos de milho apresentam maior DIVMS que o sorgo. A amilase exógena aumentou o potencial de produção de gás (A) (P=0,01). Houve efeito de híbrido para DIVMS (P<0,01). Amilase exógena aumenta a produção de gás in vitro, melhora a cinética da fermentação e aumenta a produção de nitrogênio amoniacal de grãos de milho e sorgo, mas não afeta a digestibilidade in vitro da matéria seca ou a produção de ácidos graxos de cadeia curta.


Assuntos
Técnicas In Vitro , Zea mays , Sorghum , Ruminação Digestiva , Gases , Intestinos
10.
Ars vet ; 39(2): 34-39, 2023. ilus, tab, graf
Artigo em Português | VETINDEX | ID: biblio-1438478

RESUMO

Diversos estudos relacionados à viabilidade e eficiência do uso de materiais alternativos ao globo de Vernon têm sido realizados, principalmente em decorrência ao preço elevado do cobre, componente do instrumento padrão. O objetivo foi avaliar a eficiência da utilização de caneca de alumínio como material alternativo para substituição do globo de Vernon. Para a confecção do protótipo empregou-se uma caneca de alumínio, utilizada em pistola de pintura, com capacidade de 50 ml. A caneca foi pintada com tinta preto-fosca, em duas camadas e um termômetro de mercúrio foi inserido ao centro. Para realização dos testes foram utilizados quatro equipamentos (dois globos de Vernon e dois globos negros alternativos). Foram efetuados testes prévios de comportamento temporal. Estabelecido o tempo, as temperaturas dos globos foram coletadas durante sete dias consecutivos, em três períodos, de 15 minutos cada. Os registros de temperatura foram realizados a cada cinco minutos, num total de 84 por equipamento. Os dados foram submetidos a análise de correlação de Pearson. Os resultados indicaram correlação positiva com o r2 de 0,9927, estabelecendo uma forte correlação entre os resultados de temperatura média do globo negro alternativo e globo de Vernon. Conclui-se que o globo negro alternativo do tipo caneca de alumínio mostrou-se eficiente para aferição da temperatura de globo negro em estudos de ambiência em substituição ao Globo de Vernon.(AU)


Several studies related to the feasibility and efficiency of using alternative materials to Vernon's globe have been carried out, mainly due to the high price of copper, a component of the standard instrument. The objective was to evaluate the efficiency of using an aluminum mug as an alternative material for replacing Vernon's globe. To make the prototype, an aluminum mug was used, used in a paint gun, with a capacity of 50 ml. The mug was painted with matte black paint, in two layers and a mercury thermometer was inserted in the center. Four pieces of equipment were used to carry out the tests (two Vernon globes and two alternative black globes). Previous temporal behavior tests were carried out. Once the time was established, the globes' temperatures were collected for seven consecutive days, in three periods of 15 minutes each. Temperature records were taken every five minutes, a total of 84 per equipment. Data were subjected to Pearson's correlation analysis. The results indicated a positive correlation with the r2 of 0.9927, establishing a strong correlation between the mean temperature results of the alternative black globe and Vernon's globe. It is concluded that the alternative black globe of the aluminum mug type proved tobe efficient for measuring the temperature of the black globe in ambience studies, replacing the Vernon Globe.(AU)


Assuntos
Bem-Estar do Animal , Proteínas Anticongelantes/análise , Alumínio/química
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