354 resultados para Cones. Bastonetes. Células ganglionares. Dopamina. Olho. Visão


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Mice foetus were killed between 13 and 16 days of the gestational period and their molar tooth germs grafted into the anterior chamber of the eye. The hosts were injected either with 6.25 mg/Kg or with 125 mg/Kg of cyclophosphamide and killed 15 days later. The cyclophosphamide irreversibly, interferes on tooth germ development causing either its total degeneration or an alteration on its morphology forming hypodeveloped tooth germs; its action is directly proportional to the foetus age and to the dose used; it does not induce the formation of osteodentin while some predentin partial cell inclusion may occur.

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The subject of this work was to study a hardening procedure for gutta-percha points, in order to make ease their introduction in very curved root canals. Gutta-percha points of different brands and dimensions were submitted to treatment with alcohol 96 degrees for 1 to 3 days. After this treatment the weight necessary to make a bending of 35 degrees on the tip of the gutta-percha was evaluated. The obtained results were submitted to statistic analysis and the following conclusions can be observed: a. The treatment with alcohol make hard the gutta-percha points in a significant level. b. There was not significant differences between the results obtained with more than one day of alcohol treatment. c. The treatment with alcohol do not make hard all the brands of gutta-percha points.

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Persistent cough leads individuals to seek for medical assistance. Clinical investigation, however, may not reveal any alteration within the clinic's sphere of action. Often enough, some professionals treat the symptom as a disease, introducing several medicines, unsuccessfully. The author's experience, as an otolaryngologist, allows to state that many of these professionals ignore the upper aerodigestive tract as a cough-generator site. The present work discusses the alterations on the mentioned tract, which may provoke the cough reflex, reviewing, initially, the cough mechanism and the localization of the specific receptors. Cough is produce by stimulus at the receptor level or far from it. In upper and lower parts of the aerodigestive tract secretions may run to several directions. Secretion from the paranasal sinus is a frequent cause of cough. Acute sinusitis may occur insidiously bringing about the chronification of the inflammation with cough being the only great apparent symptom. Nasal and dental alterations favor sinusal infection. Signs and symptoms, even if minimum, may be detected through an accurate anamnesis. Nasal allergy, laryngitis, post nasal dripping and septal deviation may also produce cough. The ORL examination is, therefore, imperative, and no radiologic examination can substitute for it. An inadequate treatment, particularly of the sinusitis, may bring about a worsening and extension of the initial condition.

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This paper deals with the ultrastructural study of mature vampire bat Sertoli cells and their relationships with the different stages of testicular germ cells. In vampire bat seminiferous epithelium there are different types of junctional specializations among Sertoli cells and among Sertoli cells and different germ cells, with special emphasis to tight junctions and to junctions like as desmosomes. Ectoplasmic junctions through the Sertoli cells, including the smooth ER, are observed. These cellular interactions and their cytophysiological roles are discussed. Also are related some ultrastructural peculiarities of the Sertoli cell nucleus, nucleolus, cytoplasmic organelles and lipidic inclusions.

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Cara inchada of cattle (CI) is a periodontitis which occurs in calves in several regions of Brazil. Its progressive lesions, caused mainly by Bacteroides melaninogenicus and Actinomyces pyogenes, could lead to loss of teeth, malnutrition and possibly death of affected animals. For further analysis of the pathogenesis of this disease the influence of streptomycin on the adherence of the causative bacteria to oral epithelial cells of cattle was determined. Production of streptomycin by soil bacteria (Actinomycetes) in Brazil had been suggested by several authors. In our studies, streptomycin in subinibitory concentrations increased tenfold the rate of adherence with B. melaninogenicus (from 0.4 to 4.0 bacteria per bovine epithelial cell). On the contrary, streptomycin did not influence significantly the adherence of A. pyogenes nor streptococci of the viridans group. Thus, streptomycin could be a contributing factor to the development of the periodontal infections with B. melaninogenicus.

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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.

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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.

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Maytenus ilicifolia and Maytenus aquifolia (Celastraceae) both designated espinheira-santa have proven anti-ulcer activity. Morphologic similarities between leaves of espinheira-santa and mata-olho (Sorocea bonplandii), has motivated fakes in the market of phytotherapy. The present work consisted of the anatomical study, including stem and leaf, of the species M. ilicifolia, M. aquifolia and S. bomplandii. Samples of adult leaves and stem of plants located in the cities of Maringá and Marialva were collected. Both are located in the northwest region of Paraná State. The botanical material was prepared with using usual techniques of anatomy. The leaves of both Maytenus species presented great similarities, characterizing itself for the presence of epidermal cells with straight walls, biseriate palisade tissue, petiole vascular system represented by unique amphicribal bundle and sclereids, which were present in the stems of these two species. S. bomplandii leaves differed of Maytenus species for presenting epidermal cells with undulated walls, uniserite palisade tissue, petiole vascular system represented by many collateral bundles and gelatinous fibres. Non-glandular trichomes, glandular trichomes, and laticifer only occur in S. bomplandii.

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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.

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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.

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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.

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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.

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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.

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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.

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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.