987 resultados para tegumentary glands


Relevância:

10.00% 10.00%

Publicador:

Resumo:

IntroductionThe influx and efflux of military personnel in the possible endemic areas of leishmaniasis provided the impetus for research on the sandflies on Marambaia Island.MethodsSandflies were collected with light traps installed in the 3 ecotypes of 3 areas chosen for their particular landscape aspects.ResultsIn 2009, were collected 32,006 specimens of sandflies belonging to 13 species. The species that showed highest density were Nyssomyia intermedia and Migoneimyia migonei.ConclusionsN. intermedia and M. migonei are the principal vectors of American tegumentary leishmaniasis (ATL) in Brazil; thus, extension studies related to the eco-epidemiology of these species of Marambaia Island are essential.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

RESUMO: Mutações em genes envolvidos na formação do coração e anomalias em qualquer etapa deste processo causam frequentemente malformações cardíacas, que representam o tipo mais comum de defeitos em neonatais, afetando cerca de 1% dos nascimentos por ano. Assim, estima-se que 20 milhões de pessoas sejam portadoras de um defeito cardíaco congénito. O coração da Drosophila melanogaster (mosca-da-fruta), denominado vaso dorsal, é um órgão relativamente simples que actua como uma bomba muscular, contraindo automaticamente para permitir a circulação da hemolinfa através do corpo. A formação do vaso dorsal na mosca é muito semelhante ao desenvolvimento do coração em vertebrados, representando por isso, um poderoso modelo para estudar a rede de genes e os padrões regulatórios relacionados com o desenvolvimento deste órgão. Anteriormente, nós identificámos um gene em Drosophila, darhgef10, fortemente expresso no coração em desenvolvimento e cuja deleção induz anormalidades cardíacas subtis mas prevalentes. Os mutantes para darhgef10 são viáveis e férteis no ambiente controlado de laboratório. Este trabalho teve como objectivos caracterizar fenotipicamente os mutantes nulos para darhgef10, determinar a localização subcelular da proteína dArhgef10 e investigar a base celular subjacente ao defeito no alinhamento dos cardioblastos observado nos mutantes. Os nossos resultados revelaram que a deleção de darhgef10 provoca uma severa redução da viabilidade, sem no entanto comprometer o tempo de desenvolvimento e a longevidade. Por outro lado, o aumento da expressão de darhgef10 em músculos, glândulas salivares e no disco imaginal do olho afeta drasticamente a integridade destes tecidos. A expressão ectópica de darhgef10 in vitro e in vivo revelou que a proteína está localiza no citoplasma com enriquecimento junto à membrana celular, com associação à actina F. Live imaging de embriões mutantes para darhgef10 revelou que os defeitos observados no coração podem estar associados a um defeito na adesão dos músculos alary e/ou das células pericardiais ao vaso dorsal. O homólogo humano de darhgef10, ARHGEF10, também é expresso no coração e está associação a uma maior susceptibilidade para a ocorrência de acidentes vasculares cerebrais aterotrombóticos, sugerindo que o que aprendemos sobre darhgef10 em Drosophila pode ter implicações do ponto de vista clínico para a saúde humana. ----------------------------- ABSTRACT: Mutations in genes controlling heart development and abnormalities in any of its steps frequently cause cardiac malformations, the most common type of birth defects in humans, affecting nearly 1% of births per year. Hence around 20 million adults are expected to live with a congenital heart defect. The Drosophila melanogaster heart, called dorsal vessel, is a relatively simple organ that acts as a muscular pump contracting automatically to allow the circulation of hemolymph. Drosophila heart formation shares many similarities with heart development in vertebrates providing a powerful system to study gene networks and regulatory pathways involved in heart development. We have previously identified a Drosophila gene, darhgef10, which is strongly expressed in the developing heart and when deleted, leads to flies with highly prevalent yet subtle heart abnormalities, compatible with unchallenged life in the laboratory. Our aims were to phenotypically characterize homozygous null darhgef10 mutants, characterize the subcellular localization of dArhgef10 and to study the cellular basis of the misaligned cardioblasts defect. We found that about half of darhgef10 mutants die during development. However, the survivors surprisingly have a nearly normal developmental time, adult locomotor behavior and total lifespan. Detection of transgene-derived dArhgef10 protein in vitro and in vivo using custom antibodies revealed a cytosolic protein slightly enriched in the cellular membranes and associated with F-actin. Tissue-specific darhgef10 expression disrupts the normal morphology of developing muscles, salivary glands and the eye. Live imaging of darhgef10 mutant embryos revealed that heart defect could be caused by a reduced capacity of attachment of pericardial cells and/or alary muscle to dorsal vessel. The human homolog of darhgef10 is also expressed in the heart and is a susceptibility gene for atherothrombotic stroke, suggesting that what we learn about the function of this gene and its phenotypes in Drosophila could have implications to human health.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Introduction During a diagnostic evaluation of canine visceral leishmaniasis (VL), two of seventeen dogs were found to be co-infected by Leishmania (Viannia) braziliensis and Leishmania (Leishmania) chagasi. Methods Specific polymerase chain reaction (PCR) and restriction fragment length polymorphism-PCR (RFLP-PCR) assays were performed. Results PCR assays for Leishmania subgenus identification followed by RFLP-PCR analysis in biopsies from cutaneous lesions and the spleen confirmed the presence of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) chagasi in those fragments. Conclusions This report reinforces the importance of using serological and molecular techniques in the epidemiological surveillance of canine populations in endemic areas in which both diseases are known to co-exist. In such cases, a reassessment of the control measures is required.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Venomous animals are those that, by means of a hunting and defense mechanism, are able to inject their prey with a toxic substance produced in their bodies, directly from specialized glands (e.g., tooth, sting, spur) through which the poison passes. Millipedes are poisonous animals; they can be harmful to humans, and their effects usually manifest as erythematous, purpuric, and cyanotic lesions; local pain; and paresthesia. Here, we report a case of skin contact with a millipede for 6h resulting in skin lesions similar to blue toe syndrome.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Abstract:INTRODUCTION:The Montenegro skin test (MST) has good clinical applicability and low cost for the diagnosis of American tegumentary leishmaniasis (ATL). However, no studies have validated the reference value (5mm) typically used to discriminate positive and negative results. We investigated MST results and evaluated its performance using different cut-off points.METHODS:The results of laboratory tests for 4,256 patients with suspected ATL were analyzed, and 1,182 individuals were found to fulfill the established criteria. Two groups were formed. The positive cutaneous leishmaniasis (PCL) group included patients with skin lesions and positive direct search for parasites (DS) results. The negative cutaneous leishmaniasis (NCL) group included patients with skin lesions with evolution up to 2 months, negative DS results, and negative indirect immunofluorescence assay results who were residents of urban areas that were reported to be probable sites of infection at domiciles and peridomiciles.RESULTS:The PCL and NCL groups included 769 and 413 individuals, respectively. The mean ± standard deviation MST in the PCL group was 12.62 ± 5.91mm [95% confidence interval (CI): 12.20-13.04], and that in the NCL group was 1.43 ± 2.17mm (95% CI: 1.23-1.63). Receiver-operating characteristic curve analysis indicated 97.4% sensitivity and 93.9% specificity for a cut-off of 5mm and 95.8% sensitivity and 97.1% specificity for a cut-off of 6mm.CONCLUSIONS:Either 5mm or 6mm could be used as the cut-off value for diagnosing ATL, as both values had high sensitivity and specificity.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Biochemical and hematimetric indicators of inflammation and cell damage were correlated with bilirubin and hepatic and pancreatic enzymes in 30 chronic male alcoholics admitted into psychiatric hospital for detoxification and treatment of alcoholism. Aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, and total bilirubin were altered, respectively, in 90%, 63%, 87%, 23% and 23% of the cases. None of the indicators of inflammation (lactic dehydrogenase, altered in 16% of the cases; alpha-1 globulin, 24%; alpha-2 globulin, 88%; leucocyte counts, 28%) was correlated with alterations of bilirubin or liver enzymes. Lactic dehydrogenase was poorly sensitive for detection of hepatocytic or muscular damage. Alterations of alpha-globulins seemed to have been due more to alcohol metabolism-induced increase of lipoproteins than to inflammation. Among indicators of cell damage, serum iron, increased in 40% of the cases, seemed to be related to liver damage while creatine phosphokinase, increased in 84% of the cases, related to muscle damage. Hyperamylasemia was found in 20% of the cases and significantly correlated with levels of bilirubin, alkaline phosphatase and gamma-glutamyltransferase. It was indicated that injuries of liver, pancreas, salivary glands, and muscle occurred in asymptomatic or oligosymptomatic chronic alcoholics.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We prospectively studied the effects of the ligation of the inferior thyroid artery (ITA) on postoperative hypoparathyroidism in 48 patients who underwent functional subtotal thyroidectomy. Patients were randomized into two groups: A, with bilateral ligation of the ITA and B, without ligation of the ITA. Parathyroid function was checked preoperatively and after surgery by clinical examination and measurement of total calcium, intact PTH, urinary calcium, and AMPc. RESULTS: A significant incidence of postoperative hypocalcemia occurred: 17% in group A and 13% in B on the 4th postoperative day. Six months later, the incidence was 5% in Group A and 0% in Group B. These differences were not statistically significant between the two groups, and neither were any of the other clinical and laboratory observations. CONCLUSION: The ligation of the ITA was not an important causal factor for the occurrence of postoperative hypocalcemia after subtotal thyroidectomy.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Salivary gland tumors constitute a highly heterogeneous histopathologic group. There are few epidemiological studies of large series of benign and malignant salivary gland tumors in Brazil. MATERIAL AND METHODS: Hospital records of 124 patients with salivary gland tumors diagnosed from January 1993 to December 1999 were reviewed. The patients were analyzed according to gender, age, size, location, and histopathology of the tumor. RESULTS AND CONCLUSIONS: Patients with benign and malignant tumors presented with a mean age of 47.7 and 48.8 years, respectively. The frequency of benign tumors was 80% (n = 99) and malignant tumors 20% (n = 25). Tumors were localized in the parotid gland 71% (n = 88), in the submandibular gland 24% (n = 30), and in the minor salivary glands 5% (n = 6). The most common benign tumors were pleomorphic adenoma in 84% (n = 84) and Warthin's tumor in 13% (n = 13). Among malignant tumors, mucoepidermoid carcinoma was the most common in 52% (n = 13), adenoid cystic carcinoma occurred in 20% (n = 5), and carcinoma ex pleomorphic adenoma was detected in 12% (n = 3).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

PURPOSE: The aim of this investigation was to quantitatively evaluate C-cells in colloid goiters, analyzing 36 thyroids that were obtained through thyroidectomy from 24 patients with goiter and 12 normal glands from adult patients without thyroid disease, which were used as the control group. MATERIAL AND METHODS: On average, 6 different thyroid areas were sampled and labeled by immunohistochemistry with a monoclonal anticalcitonin antibody, utilizing the avidin-biotin-peroxidase complex. C-cells were counted in fields measuring 1 square centimeter, and the mean number of cells per field was then calculated. Data were statistically analyzed using the Mann-Whitney test. RESULTS: In the colloid goiter group, the number of C-cells ranged from 0 to 23 per field, while in normal controls they ranged from 20 to 148 per field. CONCLUSIONS: These results demonstrate a significant decrease of C-cell number in the colloid goiter group compared with control group, indicating that the hyperplastic process is restricted to follicular cells, to the detriment of C-cells, which probably cease to receive trophic stimuli.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

PURPOSE: To test an experimental model of chemical mammary carcinogenesis induction in rats. METHODS: Twenty young virgin Sprague-Dawley female rats, aged 47 days, received 20 mg of 7,12-dimethylbenz(a)anthracene (DMBA) intragastrically by gavage. Afterwards, at 8 and 13 weeks, their mammary glands were examined. At the end of the experiment, the animals were sacrificed, and the mammary tumors were measured and weighed. Tumor fragments were analyzed using light microscopy. RESULTS: Eight weeks after DMBA injection, 16 rats presented at least 1 breast tumor (80%). After 13 weeks, all of them (100%) developed breast carcinomas that were confirmed by histopathological analysis. CONCLUSION: This experimental animal model of chemical mammary induced carcinogenesis is feasible and can be used in further experiments on the role of tumorigenic biomodulator substances.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Two new species of Bucephalidae (Trematoda) are described from fishes of the Brazilian Amazon. Glandulorhynchus turgidus gen. et sp. n. from Hydrolycus sp. differs from all others in the family by having conspicuous glands near the anterior extremity and an expanded uterus used for storing eggs. Prosorhynchus piranhus sp. n. from Serrasalmus rhombeus is characterized as having a small rhynchus and pharynx, and a large cirrus sac.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Previous studies on monocarboxylate transporters expression in prostate cancer (PCa) have shown that monocarboxylate transporter 2 (MCT2) was clearly overexpressed in prostate malignant glands, pointing it out as a putative biomarker for PCa. However, its localization and possible role in PCa cells remained unclear. In this study, we demonstrate that MCT2 localizes mainly at peroxisomes in PCa cells and is able to take advantage of the peroxisomal transport machinery by interacting with Pex19. We have also shown an increase in MCT2 expression from non-malignant to malignant cells that was directly correlated with its peroxisomal localization. Upon analysis of the expression of several peroxisomal ß-oxidation proteins in PIN lesions and PCa cells from a large variety of human prostate samples, we suggest that MCT2 presence at peroxisomes is related to an increase in ß -oxidation levels which may be crucial for malignant transformation. Our results present novel evidence that may not only contribute to the study of PCa development mechanisms but also pinpoint novel targets for cancer therapy.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

ABSTRACT Nodal glands are found in one third of the Polygalaceae genera and have valuable taxonomic, ecological and evolutionary significance. In Brazil, they occur in five of the eleven genera already registered. However, there is still a controversy regarding the origin of these structures. The objective of this study was to characterize the morphology and the origin of nodal glands inCaamembeca spectabilis, in order to increase the structural and functional knowledge of these glands in the genera. Samples of nodal regions were collected, fixed and processed according to the methods of light microscopy and electron scanning. Ants were observed and identified along the stem axis. The glucose in exudate allows us to classify these glands as extrafloral nectaries. They are located in pairs on the nodal region. However, its origin is in the leaf trace. In the longitudinal section, the nectaries were present in the apex of cells with anticlinal walls impregnated with suberin, which represents the first record for the family. In this region there is also the formation of a hole by lysis. The secretory tissue is surrounded by phloem. Xylem vessels were observed only on the basis of the nectary, where there are also idioblasts with crystals in druse type. We have studied the ontogeny of the glands nodal in Caamembeca spectabilis and unveiled that these glands are linked to the leaves as stipular nectaries. In addition, the new findings presented here may add support for the understanding of morphology and anatomy of nodal glands in Caamembeca.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Silk fibroin is a commonly available natural biopolymer produced in specialized glands of arthropods, such as silkworms or spiders, scorpions, mites, bees and flies. This biopolymer has a long history of use in textile production and also as sutures or treatment of skin wounds. Silk fibroin has been increasingly explored in other areas of biomedical science where we can find a higher morphological diversification of silk biomaterials like films, electrospun fibers, 3D porous scaffolds or nanoparticles. In recent years it has been demonstrated that fibroin is an excellent material for active components in optical devices. This new application opens the way towards the development of multifunctional optoelectronic devices, which in perspective can be made fully biocompatible and eventually bioresorbable. Moreover, fibroin can be added to other biocomponents in order to modify the biomaterial properties leading to optimized and total different functions. These improvements can go from higher cell adhesion in tissue engineering or enhanced optical transparency, smoothness or flexibility in optoelectronic devices. The tuning and completely understanding of silk fibers physicochemical properties and interaction with other elements are of crucial importance for the improvement of already existent silk-based materials and the basis for the development of new products.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Silk fibroin (SF) is a commonly available natural biopolymer produced in specialized glands of arthropods, with a long history of use in textile production and also in health cares. The exceptional intrinsic properties of these fibers, such as self-assembly, machinability, biocompatibility, biodegradation or non-toxicity, offer a wide range of exciting opportunities [1]. It has long been recognized that silk can be a rich source of inspiration for designing new materials with tailored properties, enhanced performance and high added value for targeted applications, opening exciting new prospects in the domain of materials science and related technological fields, including bio-friendly integration, miniaturization and multifunctionalization. In recent years it has been demonstrated that fibroin is an excellent material for active components in optics and photonics devices. Progress in new technological fields such as optics, photonics and electronics are emerging [2,3]. The incorporation of polymer electrolytes as components of various devices (advanced batteries, smart windows, displays and supercapacitors) offers significant advantages with respect to traditional electrolytes, including enhanced reliability and improved safety. SF films are particularly attractive in this context. They have near-perfect transparency across the VIS range, surface flatness (together with outstanding mechanical robustness), ability to replicate patterned substrates and their thickness may be easily tailored from a few nanometers to hundreds of micrometers through spin-casting of a silk solution into subtract. Moreover, fibroin can be added to other biocomponents or salts in order to modify the biomaterial properties leading to optimized and total different functions. Preliminary tests performed with a prototype electrochromic device (ECD) incorporating SF films doped with lithium triflate and lithium tetrafluoroborate (LiTFSI and LiBF4, respectively) as electrolyte and WO3 as cathodic electrochromic layer, are extremely encouraging. Aiming to evaluate the performance of the ion conducting SF membranes doped with LiTFSI and LiBF4 (SF-Li), small ECDs with glass/ITO/WO3/SF-Li/CeO2-TiO2/ITO/glass configuration were assembled and characterized. The device exhibited, after 4500 cycles, the insertion of charge at -3.0 V reached –1.1 mC.cm-2 in 15 s. After 4500 cycles the window glass-staining, glass/ITO/WO3/Fibrin-Li salts electrolyte/CeO2-TiO2/ITO/glass configuration was reversible and featured a T  8 % at λ = 686 nm