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The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.
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Deshidratación , Malus , Clorofila A , Prolina , AzúcaresRESUMEN
The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.
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Cucurbitaceae , Ácido Salicílico , Hidroponía , Ácido Salicílico/farmacología , Estrés Salino , Sales (Química) , AguaRESUMEN
OBJECTIVE: Herpes simplex virus encephalitis (HSVE) represents the most common cause of sporadic encephalitis in humans. The development of intracerebral hematomas is rare and late during the course of HSVE. To report a case of a patient with HSVE who initially presented a diffuse intracranial hemorrhage with predominant intraventricular bleeding. CASE REPORT: A 66-year-old man was admitted to the Emergency Department with acute headache. Antecedents: alcohol consumption and ethylic hepatopathy. The brain computed tomography showed acute tetraventricular hemorrhage and hydrocephalus. The blood analysis showed pancytopenia and alteration of all hepatic parameters. After external drainage of cerebrospinal fluid the patient presented a worsening of headache, disorientation, mild left hemiparesis, neck stiffness and temperature of 37.6 °C. The cerebrospinal fluid was hemorrhagic, with 3 lymphocytes/mm3, 60 mg/dL of proteins and PCR positive for Herpes simplex virus type 1. The patient improved with intravenous acyclovir, however he experienced several medical complications which caused his dead. DISCUSSION: The patient presented an atypical cerebral bleeding related to HSVE because the development of hematoma was early and the topography of hemorrhage was basically intraventricular. Probably, both atypical characteristics were related to thrombocytopenia and severe coagulation disorder. This case expands the spectrum of cerebrovascular disorders associated with HSVE.
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Hemorragia Cerebral/etiología , Encefalitis por Herpes Simple/complicaciones , Anciano , Hemorragia Cerebral/diagnóstico , Encefalitis por Herpes Simple/diagnóstico , Humanos , MasculinoRESUMEN
DL-glutamic acid monohydrate crystal was synthesized from an aqueous solution by slow evaporation technique. The crystal was submitted to high-pressure (1 atm-14.3 GPa) to investigate its vibrational behavior and the occurrence of phase transitions. We performed Raman spectroscopy as probe and through the analysis of the spectra we discovered three structural phase transitions. The first one occurs around 0.9 GPa. In this phase transition, glutamic acid molecules suffer modifications in their conformations while water molecules are less affected. The second phase transition at 4.8 GPa involves conformational changes related to CO2-, NH3+ units and the water molecules, while the third one, between 10.9 and 12.4 GPa, involves motions of several parts of the glutamic acid as well as the water molecules. Considering the dynamic of high pressure, the second phase of DL-glutamic acid monohydrate crystal presented a better stability compared with the second phase of its polymorphs α and ß L-glutamic acid. In addition, water molecules seem to play important role on this structural stability. All changes are reversible.
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Ácido Glutámico/química , Conformación Molecular , Transición de Fase , Presión , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Espectrometría RamanRESUMEN
Sprentascaris mahnerti (Nematoda: Raphidascarididae) collected from Loricariichthys labialis (Siluriformes: Loricariidae) in the Pantanal wetlands, State of Mato Grosso do Sul (Brazil), was redescribed using light and scanning electron microscopy (SEM), and genetically characterised along with two other raphidascaridids: Raphidascaroides brasiliensis and Ro. moraveci. Due to the systematic discussion regarding Raphidascaris and Sprentascaris, as well as the poor knowledge about the phylogenetic relationships within Raphidascarididae, phylogenies were reconstructed based on partial sequences of the 18S and 28S nuclear rRNA gene, the nuclear ITS1-5.8S-ITS2 and the cytochrome c oxidase subunit I (cox1) mtDNA. Morphological study of S. mahnerti, confirmed some previously described features, revealed new characteristics and permitted to elucidate some inconsistencies noted in the literature. Morphological and genetic characterisation of S. mahnerti supported its validity. Phylogenetic reconstructions supported the monophyly of Sprentascaris, which has three pairs of interlabial conspicuous cuticular projections as a synapomorphy. The relationships among several lineages of raphidascaridids were unsolved, albeit Goezia and Ichthyascaris formed well-supported monophyletic assemblages, in which the first included species with no relations regarding the habitat of hosts and the geographic origin. The present findings represent one more step towards the understanding of the interrelationships of raphidascaridid nematodes. In this sense, Sprentascaris should be considered valid as an independent lineage from Raphidascaris.
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Ascaridoidea/clasificación , Ascaridoidea/genética , Enfermedades de los Peces/parasitología , Filogenia , Animales , Ascaridoidea/ultraestructura , Brasil , Complejo IV de Transporte de Electrones/genética , Femenino , Agua Dulce/parasitología , Masculino , Microscopía Electrónica de Rastreo , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genéticaRESUMEN
INTRODUCCIÓN La caries dental ha sido convencionalmente manejada mediante la remoción no selectiva del tejido carioso (remoción total), sin embargo, los efectos adversos de este procedimiento han promovido la utilización de técnicas de remoción de caries conservadoras (remoción selectiva), pero aún existe controversia respecto a su efectividad. MÉTODOS Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metaanálisis, preparamos tablas de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos siete revisiones sistemáticas que en conjunto incluyeron siete estudios primarios, todos ellos correspondientes a ensayos aleatorizados. Concluimos que la remoción selectiva de caries podría disminuir la necesidad de tratamiento de endodoncia y el riesgo de exposición pulpar en dientes con caries profundas, pero la certeza de la evidencia es baja. No existe claridad de que la remoción selectiva de caries disminuya el riesgo de aparición de signos y síntomas de patología pulpar y el riesgo de fracaso de las restauraciones ya que la certeza de la evidencia es muy baja.
INTRODUCTION Dental caries have been conventionally managed by non-selective removal of carious tissue (total complete removal); however, the adverse effects of this procedure have promoted the use of conservative caries removal techniques (selective removal), but there is still controversy regarding its effectiveness. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified seven systematic reviews including seven studies overall, of which all were randomized trials. We concluded that selective caries removal may decrease the need for root canal treatment and the risk of pulp exposure in teeth with deep caries, but the certainty of the evidence is low. It is not clear whether the selective removal of caries reduces the risk of appearance of signs and symptoms of pulp disease and the risk of restorations failure, as the certainty of the evidence is very low.
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Humanos , Caries Dental/terapia , Tratamiento Conservador/métodos , Revisiones Sistemáticas como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Medición de Riesgo , Caries Dental/patología , Endodoncia RegenerativaRESUMEN
Janus particles interfacially self-assemble into different structures when incorporated into multiphase systems. Dissipative particle dynamics simulations are employed herein to investigate the interplay between aggregation mechanisms and phase separation in polymer blends. Shorter rods with a standing configuration become increasingly "caged" or trapped in larger aggregates as weight fraction increases, which is reflected in the way that their diffusion is coupled to their aggregation rates. Janus rods of higher aspect ratios that are tilted at the interface aggregate side-by-side and are able to hinder phase separation kinetics. This is due to a combination of individual Janus rod conformations at the interface, their intrinsic aggregation mechanisms, aggregate fractal dimension, and aggregation rates, and can also be traced back to the scaling of the diffusion coefficient of aggregates with their size. Findings presented provide insight into the mechanisms governing two dimensionally growing colloidal aggregates at fluid interfaces, more specifically, those associated with Janus particles, and shed light on the potential of these systems in paving the way for designing new functional materials.
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Diaphanocephalus galeatus collected from the small intestine of the lizard Dracaena paraguayensis in the Pantanal wetlands, State of Mato Grosso do Sul, Brazil, is redescribed. Genetic characterization and observations using scanning electron microscopy (SEM) were performed for the first time. The vouchers of D. galeatus and the type specimens of its congeners, deposited in the Coleção Helmintológica do Instituto Oswaldo Cruz (CHIOC), were consulted. Light and SEM observations revealed several undescribed features of D. galeatus, i.e. structure of the cephalic end and of the buccal capsule, position and morphology of deirids, presence of phasmids in females and presence of unpaired papilla on the membranous projection that covers the genital cone in males. After observation of the specimens deposited in the helminthological collection, D. jacuruxi is considered a synonym of D. galeatus, and D. diesingi, despite its incomplete description, is tentatively retained as valid due to the poor condition of the type material. The results also indicated low host specificity of D. galeatus, contradicting previous assertions. Genetic comparisons using patristic distances and phylogenetic trees generated from sequences of the 28S rRNA nuclear gene indicated that D. galeatus is closer to the taxa within Ancylostomatoidea and Strongyloidea than any lineage of Metastrongyloidea or Trichostrongyloidea. However, most of the nodal supports were low. Based on the genetic and morphological characterization, the validity of D. galeatus was confirmed. These data may serve for further comparative approaches for different populations of the parasite, from different hosts in different geographical areas, mitigating taxonomic confusions.
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Lagartos/parasitología , Nematodos/clasificación , Filogenia , Animales , Brasil , ADN Ribosómico/genética , Femenino , Especificidad del Huésped , Intestino Delgado/parasitología , Masculino , Microscopía Electrónica de Rastreo , Nematodos/anatomía & histología , Nematodos/ultraestructura , ARN Ribosómico 28S/genéticaRESUMEN
Raphidascaris (Sprentascaris) andersoni n. sp. (Nematoda: Raphidascarididae) collected in the intestine of the humphead cichlid Gymnogeophagus balzanii (Perugia) from the Pantanal wetlands, State of Mato Grosso do Sul (Brazil) is described and genetically characterized. The new species differs from its congeners mainly by having a conspicuous papilla-like formation slightly anterior to the cloacal aperture. Furthermore, males of R. (S.) lanfrediae and R. (S.) mahnerti have caudal alae, and R. (S.) hypostomi and R. (S.) pimelodi lack lateral alae, whereas in the new species caudal alae are absent and lateral alae present. The remaining congeners, namely, R. (S.) marano and R. (S.) saltaensis differ from Raphidascaris (Sprentascaris) andersoni n. sp. mainly because males have three pairs of postcloacal papillae (vs five pairs). In the phylogenetic reconstructions, using three nuclear genetic markers (18S, ITS1-5.8S-ITS2 and 28S rDNA) and one mitochondrial (cox1 mtDNA), the new species was separated from other representatives of Raphidascarididae, and the absence of monophyly in Hysterothylacium and Raphidascaroides was confirmed. Moreover, the subgenera Sprentascaris and Ichthyascaris appeared to be monophyletic. Therefore, even though Raphidascaris (Raphidascaris) was apparently not monophyletic, the subgenera of Raphidascaris should be re-erected as valid genera. The updated diagnoses of Ichthyascaris, Raphidascaris and Sprentascaris are given. The present study represents the first parasitological survey in G. balzanii.
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Infecciones por Ascaridida/veterinaria , Ascaridoidea/clasificación , Ascaridoidea/crecimiento & desarrollo , Enfermedades de los Peces/parasitología , Animales , Infecciones por Ascaridida/parasitología , Ascaridoidea/genética , Ascaridoidea/aislamiento & purificación , Brasil , Cíclidos/parasitología , ADN de Helmintos/genética , ADN Ribosómico/genética , Femenino , Masculino , Filogenia , HumedalesRESUMEN
This study investigated whether the body morphology of the tetra fish Astyanax lacustris (previously Astyanax asuncionensis) varied between populations inhabiting one lagoon (a lentic, shallow environment, with great habitat complexity created by aquatic macrophytes) and an adjacent river (a deeper, lotic environment where aquatic macrophytes are scarce) in a seasonally flooded wetland, despite population mixing during the wet season. Morphological differences matched a priori predictions of the theory relating functional body morphology and swimming performance in fishes between lagoon and river habitats. Observed morphological variation could have resulted from adaptive habitat choice by tetras, predation by piscivores and adaptive phenotypic plasticity during development.
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Characidae/anatomía & histología , Natación , Humedales , Animales , Brasil , Characidae/fisiología , Ecosistema , Inundaciones , Conducta Predatoria , Ríos , Estaciones del AñoRESUMEN
Stroke is one of the leading causes of death and disability worldwide. However, current therapies only reach a small percentage of patients and may cause serious side effects. We propose the therapeutic use of retinoic acid-loaded nanoparticles (RA-NP) to safely and efficiently repair the ischaemic brain by creating a favourable pro-angiogenic environment that enhances neurogenesis and neuronal restitution. Our data showed that RA-NP enhanced endothelial cell proliferation and tubule network formation and protected against ischaemia-induced death. To evaluate the effect of RA-NP on vascular regulation of neural stem cell (NSC) survival and differentiation, endothelial cell-conditioned media (EC-CM) were collected. EC-CM from healthy RA-NP-treated cells reduced NSC death and promoted proliferation while EC-CM from ischaemic RA-NP-treated cells decreased cell death, increased proliferation and neuronal differentiation. In parallel, human endothelial progenitor cells (hEPC), which are part of the endogenous repair response to vascular injury, were collected from ischaemic stroke patients. hEPC treated with RA-NP had significantly higher proliferation, which further highlights the therapeutic potential of this formulation. To conclude, RA-NP protected endothelial cells from ischaemic death and stimulated the release of pro-survival, proliferation-stimulating factors and differentiation cues for NSC. RA-NP were shown to be up to 83-fold more efficient than free RA and to enhance hEPC proliferation. These data serve as a stepping stone to use RA-NP as vasculotrophic and neurogenic agents for vascular disorders and neurodegenerative diseases with compromised vasculature.
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Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/patología , Tretinoina/administración & dosificación , Animales , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Humanos , Isquemia/tratamiento farmacológico , Isquemia/patología , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/química , Neovascularización Fisiológica/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Polímeros/química , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/patologíaRESUMEN
This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28 ± 5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09% ± 16.59%, P=0.001), but there was no change in the experimental arm (-12.48% ± 12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.
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Endotelio Vascular/fisiología , Ejercicio Físico/fisiología , Adulto , Análisis de Varianza , Velocidad del Flujo Sanguíneo/fisiología , Endotelio Vascular/diagnóstico por imagen , Fuerza de la Mano/fisiología , Humanos , Masculino , Valores de Referencia , Factores de Riesgo , Resistencia al Corte/fisiología , Estadísticas no Paramétricas , Factores de Tiempo , Ultrasonografía DopplerRESUMEN
This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28±5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09%±16.59%, P=0.001), but there was no change in the experimental arm (-12.48%±12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.
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Humanos , Masculino , Adulto , Endotelio Vascular/fisiología , Ejercicio Físico/fisiología , Análisis de Varianza , Velocidad del Flujo Sanguíneo/fisiología , Endotelio Vascular/diagnóstico por imagen , Fuerza de la Mano/fisiología , Valores de Referencia , Factores de Riesgo , Resistencia al Corte/fisiología , Estadísticas no Paramétricas , Factores de Tiempo , Ultrasonografía DopplerRESUMEN
In July 2009 and July 2010 (two dry periods separated by an atypically large flood in the Pantanal wetland of Brazil), 34 and 33 specimens of the sardine fish Triportheus nematurus were collected, respectively, for the study of the metazoan parasite community of this species. Parasite ecological and community descriptors were calculated for both host samples, and possible similarities were tested statistically. Five species of metazoan parasites were identified, four of which were common to both host samples. A total of 61 metazoan parasites were collected from all fish hosts (17 specimens in July 2009 (mean: 0.5 ± 0.66 parasites/fish) and 44 specimens in July 2010 (mean: 1.33 ± 1.41 parasites/fish)). The nematode Procamallanus hilarii and the monogenean Anacanthorus sp. were the most prevalent and abundant species in 2009 and 2010, respectively. The mean total abundance and species richness were significantly higher in 2010. Parasite communities in both samples of T. nematurus were characterized by species with low prevalence, abundance, mean total abundance and species richness, thus indicating low parasite diversity. Significant differences in the prevalence and abundance of P. hilarii and Anacanthorus sp. between the two samples allowed the discrimination of infracommunities, which were united in two distinct groups. This appears to be the first evidence that the peculiar hydrological dynamics of the southern Pantanal wetland (Brazil) exert an important influence over the structure of the parasite community.
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Characiformes/parasitología , Enfermedades de los Peces/parasitología , Parásitos/clasificación , Parásitos/aislamiento & purificación , Enfermedades Parasitarias en Animales/parasitología , Animales , Biodiversidad , Brasil/epidemiología , Enfermedades de los Peces/epidemiología , Carga de Parásitos , Enfermedades Parasitarias en Animales/epidemiología , Prevalencia , HumedalesRESUMEN
Avaliaram-se as alterações histológicas e a expressão das metalotioneínas (MTs) e das proteínas de choque térmico (Hsp70) nos rins de ratos Wistar após a exposição ao fungicida tirame. Os animais foram distribuídos em três grupos: grupo dieta-padrão; grupo dieta-padrão+óleo de milho; e grupo tirame. Foram encontradas diferenças significativas (P<0,05) na evolução do peso corporal entre os ratos do grupo tirame e os dos grupos controle e óleo de milho, e não foram verificadas lesões histológicas evidentes nos rins dos animais. Foram encontradas diferenças entre os animais do grupo exposto ao tirame e os dos grupos controle e óleo quanto às características histomorfométricas relativas ao corpúsculo renal - exceto para a proporção área da cápsula de Bowman:área do glomérulo - e relativas aos túbulos contorcidos proximal e distal - exceto para altura do epitélio dos túbulos distais. Nos ratos expostos ao tirame, foi observada imunomarcação positiva para as MTs, de moderada a forte, nos túbulos contorcidos da região cortical, diminuindo do córtex em direção à medula, e forte imunomarcação para as Hsp70 nas áreas do córtex e da medula, no glomérulo e nos túbulos contorcidos. Os resultados sugerem que o tirame pode ter toxicidade crônica nos mamíferos por afetar o seu crescimento e que a expressão das MTs e das Hsp70, provável resposta celular adaptativa ao estresse oxidativo causado pelo tirame, pode ser utilizada como biomarcador de exposição a este químico.
The histological alterations and the expression of metallothionein (MTs) and heat shock protein (Hsp70) in the kidney of Wistar rats after thiram fungicide exposure were evaluated. Animals were distributed into three groups: standard diet group, standard diet + corn oil group and thiram group. Significant differences were found (P<0,05) in the evolution of body weight between rats in the thiram group and those in the control and corn oil groups, and no histological lesions were evident in the animals' kidneys. Differences were found among animals in the group exposed to thiram and the control and oil groups regarding histomorphometric characteristics of the renal corpuscle - except for the proportion in the area of Bowman's capsule: glomerulus area - and regarding the height of the epitelium in the distal tubules. In rats exposed to thiram, a positive moderate to strong immunoexpression was observed for MTs, in the cortical convulated tubules decreasing the cortex towards the medulla, and a strong immunoexpression for Hsp70 in the cortex and medulla areas, in the glomerulus and convulated tubules. The results suggest that thiram may have chronic toxicity in mammals affecting their growth, and that the expression of MTs and Hsp70, a probable cellular adaptive response to the oxidative stress caused by thiram, may be used as a biomarker of exposure to this chemical.
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Animales , Ratas , Metalotioneína/análisis , /análisis , Ratas Wistar/anatomía & histología , Ratas Wistar/anomalías , Antifúngicos , Estrés OxidativoRESUMEN
Ivermectin (IVM) resistance of Cooperia spp. in cattle has become an increasing and global problem. The early detection of anthelmintic resistance (AR) is important to propose strategies to slow down the development of resistance and requires sensitive, reliable, economic high-throughput and practical tests. The purpose of the present study was to apply a larval migration inhibition test (LMIT) for evaluating IVM and MOX efficacy against well-characterized field isolates of Cooperia spp. infecting cattle in Brazil. Eight isolates were used for IVM and seven for MOX. The following EC50 values of IVM were observed for the isolates: susceptible, 1.16 ηmol; Nova Alvorada do Sul I, 4.09 ηmol (RF=3.52); Campo Grande BNA, 3.57 ηmol (RF=3.07); Campo Grande TBR, 4.09 ηmol (RF=3,52); Nova Alvorada do Sul II, 2.50 ηmol (RF=2.15); Bandeirantes, 11.35 ηmol (RF=9.78); Campo Grande II, 6.03 ηmol (RF=5.20); and Porto Mortinho, 8.63 ηmol (RF=7.44). For MOX, the following EC50 values were observed: susceptible, 0.75 ηmol; Campo Grande BNA, 0.93 ηmol (RF=1.24); Campo Grande TBR, 0.36 ηmol (RF=0.48); Nova Alvorada do Sul II, 2.57 ηmol (RF=3.42); Bandeirantes, 1.43 ηmol (RF=1.90); Campo Grande II, 1.08 ηmol (RF=1.44); and Porto Mortinho, 0.49 ηmol (RF=0.65). The LMIT used in the present study can be a useful tool for in vitro evaluation of IVM, but not of MOX. However, such methodology cannot be used in large-scale studies yet. The isolates of Cooperia spp. showed various degrees of resistance to IVM, though remaining susceptible to MOX.
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Antihelmínticos/farmacología , Enfermedades de los Bovinos/parasitología , Resistencia a Medicamentos , Ivermectina/farmacología , Macrólidos/farmacología , Trichostrongyloidea/efectos de los fármacos , Animales , Brasil , Bovinos , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Larva/efectos de los fármacos , Actividad Motora/efectos de los fármacosRESUMEN
Feral pigs (S. scrofa) were introduced to the Pantanal region around 200 years ago and the population appears to be in expansion. Its eradication is considered to be impossible. The population of feral pigs in the Pantanal wetlands is currently estimated at one million. Two scientific excursions were organized. The first was conducted during the dry season, when 21 feral pigs were captured and the second was during the wet season, when 23 feral pigs were captured. Ticks were collected and the oviposition and hatching process were studied to confirm the biological success of each tick species. Three tick species were found to be feeding on feral pigs: Amblyomma cajennense, A. parvum, and Ornithodoros rostratus. During the dry season, 178 adult A. cajennense were collected, contrasting with 127 A. cajennense specimens in the wet season. This suggests that the seasonality of these ticks in the Brazilian Pantanal wetlands could be different from other regions. The results indicate that A. parvum and A. cajennense are biologically successful parasites in relation to feral pigs. A. cajennense appears to have adapted to this tick-host relationship, as well as the areas where feral pigs are abundant, and could play a role in the amplification of this tick population.
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During the study of metazoan parasites of freshwater fish in the Pantanal wetland (state of Mato Grosso do Sul, Brazil), third-stage larvae of Brevimulticaecum sp. were collected from the abdominal cavity, liver parenchyma, mesentery, skeletal muscles and stomach wall of the following species: Gymnotus inaequilabiatus, Hemisorubim platyrhynchos, Hoplias aff. malabaricus, Myleus levis, Pseudoplatystoma corruscans, Pygocentrus nattereri, Serrasalmus marginatus and Sorubim lima. The larvae exhibited the main characteristics of the genus Brevimulticaecum, such as short ventricular appendices and the position of excretory pore and excretory nucleus. This is the first report and description of larval specimens of Brevimulticaecum parasitic in these hosts, which are fish species distributed throughout South America.
Asunto(s)
Enfermedades de los Peces/parasitología , Agua Dulce , Nematodos/ultraestructura , Infecciones por Nematodos/parasitología , Humedales , Animales , Brasil , Peces , Larva , Microscopía Electrónica de Rastreo , Nematodos/clasificaciónRESUMEN
Trypanosoma (Megatrypanum) theileri from cattle and trypanosomes of other artiodactyls form a clade of closely related species in analyses using ribosomal sequences. Analysis of polymorphic sequences of a larger number of trypanosomes from broader geographical origins is required to evaluate the clustering of isolates as suggested by previous studies. Here, we determined the sequences of the spliced leader (SL) genes of 21 isolates from cattle and 2 from water buffalo from distant regions of Brazil. Analysis of SL gene repeats revealed that the 5S rRNA gene is inserted within the intergenic region. Phylogeographical patterns inferred using SL sequences showed at least 5 major genotypes of T. theileri distributed in 2 strongly divergent lineages. Lineage TthI comprises genotypes IA and IB from buffalo and cattle, respectively, from the Southeast and Central regions, whereas genotype IC is restricted to cattle from the Southern region. Lineage TthII includes cattle genotypes IIA, which is restricted to the North and Northeast, and IIB, found in the Centre, West, North and Northeast. PCR-RFLP of SL genes revealed valuable markers for genotyping T. theileri. The results of this study emphasize the genetic complexity and corroborate the geographical structuring of T. theileri genotypes found in cattle.
Asunto(s)
Enfermedades de los Bovinos/epidemiología , Bovinos/parasitología , Filogenia , ARN Lider Empalmado/genética , Trypanosoma/clasificación , Trypanosoma/genética , Tripanosomiasis , Animales , Secuencia de Bases , Brasil/epidemiología , Búfalos/parasitología , Enfermedades de los Bovinos/parasitología , ADN Protozoario/análisis , ADN Protozoario/genética , ADN Ribosómico/análisis , ADN Ribosómico/genética , ADN Espaciador Ribosómico/análisis , ADN Espaciador Ribosómico/genética , Evolución Molecular , Genotipo , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico/genética , ARN Ribosómico 5S/genética , Análisis de Secuencia de ADN , Trypanosoma/aislamiento & purificación , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitología , Tripanosomiasis/veterinariaRESUMEN
The objective of this study has been to evaluate the stability of alpha-, (gamma+beta)-, and delta-tocopherols in rice bran oil chemically refined submitted to heating in a heater without air circulation and shielded from light, at temperatures of 100 degrees C and 180 degrees C. The collection of samples took place after 48, 96, 144, 192, 240, 336, and 432 h of heating and were stored in amber-colored flasks and frozen (-18 degrees C). The analyses of tocopherols took place in accordance with the method by Chen and Bergman (2005), with slight modifications, utilizing a system of high efficiency system of liquid chromatography. It was observed that the alpha-tocopherol is present at higher concentration in rice bran oil (328.4 mg/kg), followed by (gamma+beta)-tocopherol (99.1 mg/kg), and delta-tocopherol (7.7 mg/kg). The alpha-tocopherol in rice bran oil submitted to 100 degrees C showed a reduction of 28.65% at the end of 432 h of heating whereas when submitted to 180 degrees C temperature; its reduction was of 100% at the end of 240 h of heating. The contents of (gamma+beta)- and delta-tocopherol in rice bran oil at the end of 432 h of heating at 100 degrees C was of 79.9 and 6.4 mg/100 g, respectively.