123 resultados para lamina
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The expression of immune response in the form of leukocytic infiltrate by CD3+, CD4+, and CD8+ cells in the epithelium and in the intestinal lamina propria of chicks was studied in the present work by means of immunohistochemical reaction. The chicks were treated with Lactobacillus spp. or cecal microflora (CM) and experimentally challenged or not with Salmonella enterica serovar Enteritidis. The 320 birds utilized were divided into 4 groups containing 80 chicks each and submitted to treatments with Lactobacillus reuteri, Lactobacillus salivarius, Lactobacillus acidophilus, and CM. Each group was subdivided into 4 subgroups of 20 birds each and classified into a subgroup that did not receive treatment (negative control), subgroup treated, subgroup treated and challenged with Salmonella Enteritidis, and subgroup only challenged with Salmonella Enteritidis (positive control). The results obtained show that the treatment with L. reuteri, L. salivarius, L. acidophilus, or CM and challenged or not with Salmonella Enteritidis determine immune response in the form of leukocytic infiltrate by CD3+ and CD8+ lymphocytes followed by CD4+ in the epithelium and in the lamina propria of the duodenum, jejunum, and cecum of chicks up to 12 d of age. The quantity of CD3+ lymphocytes was significantly higher (P < 0.05) in the intestine of chicks treated with L. acidophilus or CM and challenged or not with Salmonella Enteritidis; however, the higher quantity of CD8+ lymphocytes was in the intestine of chicks treated with CM and challenged with Salmonella Enteritidis. The duodenum was the segment in which the immune response by T cells (CD3+, CD4+, and CD8+) was stimulated with the greatest intensity, followed by, respectively, the jejunum and cecum. The quantity of CD3+ lymphocytes present in the duodenum, jejunum, and cecum increases with the age of chicks, independent of the stimulus determined by treatments or challenge.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The author studied the structure of the tissue components of the tunicae of the terminal segment of the sigmoid sinus, particularly at the level of the transition between the sigmoid sinus, the superior bulb of the jugular vein and the first portion of the human internal jugular vein; it was established that the transition between the sigmoid sinus and the first portion of the internal jugular vein occupies the whole extension of the superior bulb of the jugular vein up to the inferior third of the first portion of this vessel. These vascular walls exhibit a structure similar to that of the dura, i.e. the tunica adventitia is formed by fascicles of collagenic fibers which describe discontinuous spirals, more open proximal to the beginning of the first portion of the internal jugular vein. Approximately in the inferior third of the first portion of the internal jugular vein, there appear fascicles of smooth muscle fibers which are arranged similarly to those of the venous walls. The tunica intima of these vascular segments exhibits an endothelium resting on a network of elastic fibers which may play the role of an internal elastic lamina. From the bony border of the jugular foramen there originates a connective system whose fascicles of collagenic and elastic fibers incorporate to the wall of the internal jugular vein after describing a stretch in spiral around the vascular lumen.
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Gingival mucosae of man and the adult Cebus apella monkey were fixed for 3 hr in modified Karnovsky fixative containing 2.5% glutaraldehyde, 2% formaldehyde in 0.1 M sodium phosphate buffer (pH=7.4). The specimens were postfixed in 1% osmium tetroxide in 0.1 M sodium phosphate buffer at 4°C for 2 hr, dehydrated in a graded alcohol series and embedded in Epon 812. Thick sections of 1-3 μm and ultrathin sections of 40-80 nm in thickness were cut with glass knives on an LKB ultramicrotome. The thick sections were stained with toluidine blue solution, and the grids were stained with uranyl acetate and lead citrate and examined under a Philips EM-301 electron microscope. Our observations permitted us to conclude that: both gingival mucosae, of man and the Cebus apella monkey, have lamellar nerve endings; these corpuscles are localized in the papillar space of the epithelium and do not contact closely with the basement membrane; the nerve endings are composed of an afferent fiber which subdivides several times and forms irregular flattened or discoidal expansions; the laminae of the lamellar cells are very thin near the terminal axon and are larger and irregular in shape at the peripheral portion of the corpuscle; the terminal axon shows abundant mitochondria, myelin figures, clear vesicles, and multivesicular bodies; between the axoplasm membrane and adjacent cytoplasmic lamina and between the lamellae, small desmosome type junctions are noted; and the cytoplasmic material of the lamellae cells is characterized by the presence of numerous microfilaments, microtubules, mitochondria, rough endoplasmic reticulum, and caveolae.
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Linear and stereological morphometric methods were applied to the jejunal and ileal mucosa of young, adult, and old male Wistar rats submitted to protein deficiency and rehabilitation. The animals were fed ad libitum a 2% casein diet during 42 days and then received a 20% casein diet for 30 days. Food intake, body weights, and plasma protein concentrations were recorded. In the young protein deficient rats values of mucosal height, surface area, and volume of the lamina propria were significantly lower than those of their age controls in both jejunum and ileum. In adults the differences were less marked and in the old rats all parameters were found to be unaltered by the protein deficient diet. The surface-to-volume ratio showed no significant differences between control and protein deficient in all three age groups, meaning that villus pattern did not change with protein deficiency. On rehabilitation, a striking difference between jejunum and ileum was observed in the young rats; all parameters returned to control levels in the jejunum, while they remained lower than those of their controls in the ileum.
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The testicular stroma of the vampire bat including the testicular capsula and the lamina propria of the seminiferous tubuli, was strongly PAS-positive. This observation was a possible indication of great amounts of structural glycogen and other glycoconjugates at the level of smooth muscle cells; elongated contractile cells and/or collagen frameworks of the tunica albuginea and tubular lamina propria. In the last the basement membranes of the seminiferous tubules were particularly strongly PAS positive, as an indication of their neutral mucosubstances structural composition, previously described (Malmi et al., 1987). The epithelium lining from the cavitary and surface rete testis complex showed low reactivities to mucosubstances; total proteins and lipids and oxidative enzymes studied. Although the apical granulation at the rete testis epithelium showed an intense PAS reactivity with hypothesis of glycoprotein secretion, through the rete. The PAS, Sudan Black B, NADH, MDH and LDH reactions of the testicular interstitium seem correlate to steroid metabolism (biosynthesis and secretion), at the Leydig cells level. The seminiferous epithelium generally had low reactions to all the histochemical studies realized. Particularly in the adbasal compartment the histochemical localizations of NADH diaphorase and LDH were possible related to glycolytic activities and general carbohydrates metabolism, both enzymes, and hydrogen transport, the NADH. The strong PAS, diastase and PAS, and alcian blue pH 2.5 and PAS reactions observed in the adluminal seminiferous epithelium compartment were directly related to the spermatids acrosomal glycoconjugates structuration. Also the SDH localization at this level seems to be related to the mitochondrial activities at the middle piece level in the late spermatids.
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Structurally the boundary tissue of the vampire bat seminiferous tubuli showed 2 to 5 layers of connective tissue in which elongated contractile cells and lamellar and/or fibrillar collagen were noticed. This boundary tissue forms the seminiferous tubular lamina propria. Its structure was more complex around the seminiferous tubuli near the Capsula testicularis than between the adjacent and contiguous tubuli into the testicular lobuli. The whole ultrastructural organization of the seminiferous lamina propria was described here.
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Histopathology by hematoxilin-eosin (HE) and periodic acid Schiff (PAS), concomitant direct immunofluorescence (DI) against total human immunoglobulins and against Candida albicans, was effectuated in 25 persons dentures wearers. In 5 persons without chronic athrofic candidiasis (CAC) clinical signals in the palate the HE showed wise inflammatory elements in the connective tissue and the PAS marked the continuous basal layer, the intra-cellular grains of granular layer and the uniform parakeratin on epithelial surface. In 20 others, with palatal signals of CAC, in the HE was frequent the features encountered in Candida infected and PAS revealed, beside descontinuous lamina basal and epithelial surface covered by tide and discontinuous parakeratin, the presence of round bodies few largers that presents in the granular layer, casually isolated in the medial portion of ret pegs and connective papillae. In the first 5 persons the DI against total human immunoglobulins not showed signals of the humoral immunologic phenomena, the same was valid to others 20 patients with CAC clinical aspects. However the DI with conjugate against C. albicans in the 20 cases with CAC signals revealed suitable aspects of the structures assumed by Candida in tissues. Cultures of samples obtained of the persons with CAC signals was positive in 100% to Candida, 70% presumptively albicans, against 80% of positiviness to generus Candida, 67% presumptively albicans, in the persons without CAC signals.
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Morphological and ultrastructural features of the paracloacal glands of Metachirus nudicaudatus are described. Two pairs of glands, one on the right and the other on the left of the anal canal, are formed, each consisting of a major and a minor portion. Their wall is made up of three layers: a mucosal, a muscular and an external capsule. The inner one is a mucosa the epithelium of which contains holocrine cells characterized by lipid droplets and intermediate filaments. The surrounding vascular lamina propria contains flattened tubular apocrine glands whose epithelial cells contain abundant endoplasmic reticulum, prominent Golgi complexes and numerous secretory granules. The middle layer is formed by skeletal striated muscle and the outer (third layer) consists of dense connective tissue. Each gland originates from a single duct. Transverse sections show that each duct, except in the female major gland, is in fact formed by a duct system. One of these ducts comes from the central cavity, lined by holocrine epithelium, and the others result from the branched tubular glands of the lamina propria.
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Neoplasms and tumours related to the odontogenic apparatus may be composed only of epithelial tissue or epithelial tissue associated with odontogenic ectomesenchyme. The immunohistochemical detection of different cytokeratins (CKs) polypeptides and vimentin has made it easier to explain the histogenesis of many epithelial diseases. The present study aimed to describe the immunohistochemical expression of cytokeratins 7, 8, 10, 13, 14, 18, 19 and vimentin in the epithelial components of the dental germ and of five types of odontogenic tumours. The results were compared and histogenesis discussed. All cells of the dental germ were positive for CK14, except for the preameloblasts and secreting ameloblasts, in which CK14 was gradually replaced by CK19. CK7 was especially expressed in the cells of the Hertwig root sheath and the stellate reticulum. The dental lamina was the only structure to express CK13. The reduced epithelium of the enamel organ contained CK14 and occasionally CK13. Cells similar to the stellate reticulum, present in the ameloblastoma and in the ameloblastic fibroma, were positive for CK13, which indicates a nature other than that of the stellate reticulum of the normal dental germ. The expression of CK14 and the ultrastructural aspects of the adenomatoid odontogenic tumour probably indicated its origin in the reduced dental epithelium. Calcifying odontogenic epithelial tumour is thought to be composed of primordial cells due to the expression of vimentin. Odontomas exhibited an immunohistochemical profile similar to that of the dental germ. In conclusion, the typical IF of odontogenic epithelium was CK14, while CK8, 10 and 18 were absent. Cytokeratins 13 and 19 labelled squamous differentiation or epithelial cells near the surface epithelium, and CK7 had variable expression.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The median preoptic nucleus (MnPO) is one of most important site of the lamina terminalis implicated in the regulation of hydro electrolytic and cardiovascular balance. The purpose of this study was to determine the effect of L-Type calcium channel antagonist, nifedipine, on the increase of median arterial blood pressure (MAP) induce by angiotensin II (ANG II) injected into the MnPO. The influence of nitric oxide (NO) on nifedipine antipressor action has also been studied by utilizing N W-nitro-L-arginine methyl ester (L-NAME) (40 μg 0.2 μL -1) a NO synthase inhibitor (NOSI), 7-nitroindazole (7-NIT) (40 μg 0.2 μL -1), a specific neuronal NO synthase inhibitor (nNOSI) and sodium nitroprusside (SNP) (20 μg 0.2 μL -1) a NO donor agent. We have also investigated the central role of losartan and PD123349 (20 nmol 0.2 μL -1), AT 1 and AT 2, respectively (selective non peptide ANG II receptor antagonists), in the pressor effect of ANG II (25 pmol 0.2 μL -1) injected into the MnPO. Male Wistar rats weighting 200-250 g, with cannulae implanted into the MnPO were utilized. Losartan injected into the MnPO, prior to ANG II, blocked the pressor effect of ANGII. PD 123319 only decreased the pressor effect of ANG II. Rats pre-treated with either 50 μg 0.2 μL -1 or 100 μg 0.2 μL -1 of nifedipine, followed by 25 pmol 0.2 μL -1 of ANG II, decreased ANG II-pressor effect. L-NAME potentiated the pressor effect of ANG II. 7-NIT injected prior to ANG II into the MnPO also potentiated the pressor effect of ANGII but with less intensity than that of L-NAME. SNP injected prior to ANG II blocked the pressor effect of ANG II. The potentiation action of L-NAME and 7-NIT on ANG II-pressor effect was blocked by prior injection of nifedipine. The results described in this study provide evidence that calcium channels play important roles in central ANG II-induced pressor effect. The structures containing NO in the brain, such as MnPO, include both endothelial and neuronal cells, which might be responsible for the influence of nifedipine on the pressor effect of ANG II. These data have shown the functional relationship between L-Type calcium channel and a free radical gas NO in the MnPO, on the control of ANG II-induced pressor effect acting in AT 1 and AT 2 receptors.
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This work described the lesions caused in different species of fish by gill parasites from fee-fishing at Guariba, State of São Paulo. The research was developed from april, 1997 to march to 1999, seeking to verified the kind tissues lesions from fish. Of these, forty and seven were Leporinus macrocephalus and fifty and five Piaractus mesopotamicus. About 87.2% of the L. macrocephalus, and 58.1% of the P. mesopotamicus were sponged by several species of parasites. The parasite most abundant in L. macrocephalus was Piscinoodinium pillulare, while monogenean, Trichodina sp and myxosporidian infected P. mesopotamicus. Severe gill lesions have been observed in L. macrocephalus and P. mesopotamicus caused by monogenean, P. pillulare e Trichodina sp. parasitism, such as intersticial hemorrhage, sub-epithelium edema, inflammation, epitelial hiperplasy in filaments and lamina, proliferation of mucosal cells and laminar fusion.
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The objective of the present research was to investigate the ultrastructural peculiarities of the aortic wall of the rat. Seven young adult rats were used, from which fragments of the infrarenal abdominal aorta were collected. After collection, the vascular segments were fixed and sent for analysis by scanning electron microscope. The elastic lamellae appear interposed with smooth muscular fibers; this pattern was verified mainly at the medial layer structure. Among the mural elements a well defined interrelationship was established through connective lamellae of the arterial wall. The collagen lamellae mainly provided anchoring among the elastic and smooth muscular constituents. The intimal layer showed special ultrastructural features, such as a non-continuous inner elastic lamina presented in certain sites of the vascular wall, followed by endothelial pores. This mural pattern of the abdominal aorta provided support to vascular functions such as shrinkage among the laminar composition of the arterial layers, also acting in mechanical properties of the vascular wall, such as viscoelasticity and contractility - essential actions to blood vessel hemodynamics.
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The intimal layer of the thoracic and abdominal aortic segments of Cebus apella monkey presented an evident inner elastic lamina. The medial layer of the thoracic aorta segment showed a basic lamellar elastic pattern having a medium average of 23.12 lamellae per analyzed cut sections, which appeared disposed circular and oblique relatively to the aortic lumen. The aortic adventitial layer, at this level, was formed mainly by collagen fibers, irregularly disposed between elastic fibers and smooth muscle cells. The aortic abdominal portion, in this monkey, at the suprarenal level presented a medium number of 19.12 elastic lamellae which showed a relatively disorganized and broken up pattern. At the infrarenal level the aortic medium layer showed a medium average of 11.75 elastic lamellae and next to the emission of the internal iliac arteries it was found only a middle average of 8.37 elastic lamellae intermingled with smooth muscle cells and collagen fibers whose concentration seemed to be increased next to the adventitial layer. The external elastic lamina was only present in the more distal aortic segment near to the emission of the internal iliac arteries.