433 resultados para Células estaminais embrionárias


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The developmental phases of giant cells induced by root-knot nematodes (Meloidogyne exigua) in rubber plant (Hevea brasiliensis) root were studied in relation to its number and size evaluated in eight sample dates. The results were subject to cluster analysis and principal component analysis. Sample dates were clearly distinct regarding giant cell development. As a result, the nematode infestation cycle was characterized by the following sequential phases: initial, equilibrium, choice and final.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Sparfloxacin, a difluorquinolone derivative, is a potent antibacterial agent active against a wide range of gram-positive and gram-negative organisms including Streptococcus pneumoniae, Staphylococcus aureus, methicillin resistant S. aureus, Legionella spp, Mycoplasma spp; Chlamydia spp. and Mycobacteria. A drawback of fluorquinolones is their photoreactivity. Sparfloxacin has been studied in terms of therapeutic activities. However, few reports about analytical methods of sparfloxacin are available in the literature. The aim of this study was to determine cytotoxic effects, using sparfloxacin reference substance (SPAX-SR), sparfloxacin tablets (SPAX-COMP) and sparfloxacin tablets submitted UV light during 36 hours (SPAX-COMP.36) solution, and two isolated products (7 and 9) of SPAX-SR submitted UV-C light, in concentrations of 31.25, 62.5, 125 and 250 μg/mL by in vitro mononuclear humane culture cells. The results, statistically analyzed by Teste de Tukey, showed SPAX, SPAX-COMP and SPAX-COMP.36 solutions could reduce the cells number in these conditions. These results could not be observed for products 7 or 9. These results can suggest that isolated product can be less cytotoxic than SPAX-SR, is method can also be used to identified products degradation of sparfloxacin in stability study. However, the low activity achieved with sparfloxacin submitted to UV-light is a source of concern and requires further investigation about its photodegradation mechanism.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research studied the condition (Kn) relative factor, the hepatosomatic (HSR), the splenosomatic (SSR) relation, the erythrocytes, thrombocytes and leukocytes number, the glicogen locality by PAS method in thrombocytes and leucocytes and the total protein and electrolytes serices levels in both Cyprinus carpio L. sex. The female Kn showed higher value than the males. The female HSR average values were lower than the ones observed in males, while the leukocytes, lymphocytes and neutrophils percentage number were the highest. However, the males magnesium and choride serices levels were higher than the females. The HRS average values, hematocrit, haemoglobin concentration, average corspucular volume (ACV), average corpuscular haemoglobin concentration (ACHC), erythocytes number, trombocytes, monocytes, oesinophils, positive PAS leukocyte granular (PAS-LG), and total protein, sodium, potassium and calcium serices levels did not show significant statistics difference (p> 0.05) between males and females. The PAS method showed glicogen granules into the thronbocytes, eosinophils and neutrophils cytoplasm. Nevertheless, in the PAS-LG cytoplasm, neutral glicoprotein granules were also observed. Monocytes and lynfocytes showed negative reaction to PAS. In the teleosts, the gonodas matureness presents higher relation with the factor of condition. During the reprodution period it is unlikely to find the sexual effects isolated in the hemogram, because most of the time that is not the only factor to cause dimorphism.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The morphology of the midgut epithelium cells of Anticarsia gemmatalis (Hübner) larvae is described by light and transmission electron microscopy. The midgut of A. gemmatalis is the largest portion of the digestive tract, with three distinct regions: proximal, media and distal. Its wall is formed by pseudostratified columnar epithelial tissue having four cell types: columnar, goblet, regenerative, and endocrine cells. The columnar cells are numerous and long, with the apical portion showing many lengthy microvilli and the basal portion invaginations forming a basal labyrinth. The goblet cells have a large goblet-shaped central cavity delimited by cytoplasmic projections filled with mitochondria. The regenerative cells present electron-dense cytoplasm and few organelles. The endocrine cells are characterized by electron-dense secretory granules, usually concentrated in the cytoplasm basal region.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Paracoccidioidomycosis has a variety of clinical manifestations and Paracoccidioides brasiliensis, the causative agent, may infect many tissues, most importantly the lungs. Migration of pathogenic yeasts to the endothelial cell layer is considered a prerequisite for multiple organ invasion and dissemination of the fungus. In this study of the adhesion of P. brasiliensis to endothelial cells in vitro, we investigated whether this adhesion could represent a mechanism of dissemination. To this end, as well as using conventional optical microscopy, an alternative in vivo technique was developed, to detect the presence of fungal cells in umbilical cords embedded in paraffin wax. An experiment on the migration of P. brasiliensis through an endothelial cell monolayer was carried out, and the migration of yeast cells was greater, and took less time, in control wells with no cells. The fungus crossed the monolayer, but, compared to control wells, the migration-rate was about 30% lower. This shows that the monolayer only partially blocked migration of the fungus. In these experiments, we had great difficulty finding P. brasiliensis adhered to the cell monolayer, when it was examined at different times, suggesting that migration of the fungus across the endothelial layer is very fast, and cannot normally be observed in cell culture in vitro. Thus, P. brasiliensis can cross the endothelium rapidly and probably invades deeper tissue.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mastitis is an inflammatory process in the udder that can affect the quality and quantity of milk produced causing economic losses and risks for health. Considering the somatic cell count (SCCs) as indicator of udder health and the milk yield (MY) of buffaloes from São Paulo State, this study aimed to quantify the related losses in milk due to somatic cells count (SCC). 9404 sources of information from 2198 lactations that occurred between 1997 and 2004 were analysed. There was no relation between MY and the SCCs in the buffaloes at first parity. For the second parity in the months 1, 2, 5, 6 and 7 of lactation, there was a negative and significant relationship between SCCs and MY. For parities of three or more there was a significant and negative regression coefficient during every month of lactation betrween MY and SCC. The average losses varied from 0,18 to 2,2 milk liters per unit of SCCs. The results indicated large losses observed in the miltiparous buffaloes and that this category needs received special attention in terms of udder health. The effect of farm, parity and year, must be considered comparison between animals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The retrovirus HTLV-1 is the etiological agent of the adult T-cell leukemia and HTLV-1 associated myelopathy/tropical spastic paraparesis. The proviral genome has 9,032 base pairs, showing regulatory and structural genes. The env gene encodes for the transmembrane glycoprotein gp 21. The development of methodologies for heterologous protein expression, as well as the acquisition of a cellular line that constituently expresses the recombinant, were the main goals of this work. The DNA fragment that encodes for gp 21 was amplified by nested-PCR and cloned into a pCR2.1-TOPO vector. After which, a sub-cloning was realized using the expressing vector pcDNA3.1+. The transfection of mammalian cells HEK 293 was performed transitorily and permanently. Production of the recombinant gp 21 was confirmed by flux cytometry experiments and the cell line producing protein will be used in immunogenicity assays.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mesenchymal Stem Cells (MSCs) have a high ability to renew and differentiate themselves into various lineages of conjunctive tissues. This study aimed to isolate the MSCs from murine bone marrow by using two different growth media and to characterize them with immunostaining with antivimentin antibody. We used six 2-week old BALB/c mice. Bone marrow was collected from mice's tibial and femoral channels and re-suspended in a final strength of 6x105 in Knockout-DMEM and high-glucose-DMEM media, supplemented by 10% FBS, and kept in a humidified 5% CO2 incubator at 37°C for 72 h, when non-adherent cells were removed during the change of medium. The number and density of adherent fibroblast-like colonies was greater with the Knockout-DMEM medium (within 5 days of culture) versus 10-20 days in DMEM-high glucose to get the same cellular concentration. The cells in both groups were highly positive for antivimentin antibody, characterizing them as MSCs. Obtaining MSCs as quickly as possible is essential for cell therapy field, especially when those cells are intended to be used for the repair of tissues from mesenchymal sources.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to examine the endothelial surface and to perform a morphometric analysis of the corneal endothelial cells in normal eyes of dogs using specular microscopy. Morphometric analysis with regard mean cell area and cell density was performed. Both eyes of ten mixed-breed, males and females, with 6 years of age, weighing about 15 kg euthanatized for reasons unrelated to this study were evaluated. Eyes were examined to determine that they did not have visible ocular disease and transported to the laboratory in moist chamber. Using a contact specular microscope the corneal endothelium was examined. Three images of the central corneal endothelium of each eye were obtained. The mean cell area and the cell density of the corneal endothelial cells were obtained using software for corneal endothelium analysis and density measurement. The mean cell area was 395 ± 36 μm 2 and the endothelial cell density was 2555 ± 240 cells/mm2. The present work demonstrates that the normal corneal endothelium of dog is similar to those described in human.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

HTLV-1 is the virus that causes T cell lymphoma/leukemia in adults and a neurological disorder known as HTLV-associated myelopathy or tropical spastic paraparesis. One of the transmission means is through contaminated blood and its byproducts. Because of the risk of HTLV-associated infections, screening for HTLV was introduced for Brazilian blood donors in 1993. Most of the diagnostic kits used in the national blood banks are bought from foreign companies. Brazil does not have the technology to produce this material and there is a need to produce diagnostic systems with national technology. In this study, we show the expression of gp21/HTLV-1 in Escherichia coli and its reactivity towards monoclonal antibodies and the antibodies of infected patients. Expressing these proteins is the first step towards obtaining diagnostic kits with Brazilian biotechnology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Some recent articles have reported that mesenchymal stem cells (MSCs) can be induced to express hepatocyte markers by transplanting them into animal models of liver damage, or by in vitro culture with growth factors and cytokines. In this study, the aim is to evaluate the behavior of MSCs subjected to induction of hepatocyte differentiation. The MSCs were isolated from the bone marrow of 4 normal donors, characterized and subjected to both in vitro and in vivo induction of hepatocyte differentiation. The in vitro induced cells showed morphological changes, acquiring hepatocyte-like features. However, the immunophenotype of these cells was not modified. The induced cells exhibited no increase in albumin, cytokeratin 18 or cytokeratin 19 transcripts, when analyzed by real-time RT-PCR. The expression of albumin, cytokeratin 18 and alpha fetoprotein was also unchanged, according to immunofluorescence tests. In vivo, the MSC demonstrated a potential to migrate to damaged liver tissue in immunodeficient mice. Taken together, the results suggest that bone marrow MSCs are incapable of in vitro differentiation into hepatocytes by the approach used here, but are capable of homing to damaged hepatic tissue in vivo, suggesting a role for them in the repair of the liver. This contribution to tissue repair could be associated with a paracrine effect exerted by these cells.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Lipoma is a benign tumor composed of proliferation of mature fat cells interspersed by fibrous connective tissue, blood vessels and muscles, delimited by a thin capsule. Although it represents a mesenchymal neoplasm most common human body, are rare occurrences in the oral cavity. Presents clinical and histopathological variables that do not alter their prognosis. The pathogenesis is still uncertain, although some authors consider heredity and endocrine disorders as possible causes. Occurs with greater prevalence in obese people, although their metabolism is completely independent of the normal body lipid metabolism. The clinical diagnosis of oral lipoma is the view of a nodular mass, soft, asymptomatic, flat surface, without ulceration and limited growth. The continuing growth of the lesion may cause difficulty in chewing, speech, dental adaptation and change in facial aesthetics of the patient, requiring surgical excision of the lesion. The final diagnosis is by histopathological examination. Aims to present a literature review and clinical cases of a retrospective study of 61 cases of lipomas diagnosed in pathological service between 1978 and 2009, among the 10 573 reports during that same period. It emphasizes the special cases of large lipomas of the maxillofacial region, and the importance of early diagnosis of these lesions. A dental surgeon should be able to diagnose lipomas in an early stage in the maxillofacial area avoiding a massive growth of these lesions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The transitional cell carcinoma is usually located in the trigone region of the bladder, and shows nonspecific clinical signs of the lower urinary tract such as hematuria, strangury, pollakiuria and urinary incontinence. The urethral and ureteral obstructions occur in some cases. Etiological factors such as endogenous and iatrogenic have been listed as the cause of disease. The objective of this report is to describe the process and treatment of two cases of transitional cell carcinoma presented simultaneously in two dogs, mother and daughter, that showed hematuria and post-renal azotemia, both with tumor in the trigone of bladder. After partial cystectomy ureteroneocistostomia, the diagnosis of transitional cell carcinoma was confirmed by histopathological analysis of bladder tissue. Patients received firocoxib as adjuvant to surgery. It is concluded that the surgical procedure associated with the use of specific anti-inflammatory COX-2 provided a better quality of life in both patients.