904 resultados para SENSORY ORGANIZATION


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Background: Inflammatory diseases stand out among sensory neuronopathies because, in their active phase, they can be treated with immunosuppressive agents. Immunosuppressive therapy may present severe adverse effects and requires previous inflammatory activity confirmation. Sensory neuronopathies are diagnosed based on clinical and EMG findings. Diagnostic confirmation and identification of inflammatory activity are based on sensory ganglion histopathological examination. We describe the surgical technique used for dorsal root ganglionectomy in patients with clinical/EMG diagnosis of sensory neuronopathies. Methods: The sensory ganglion was obtained from 15 patients through a small T7-T8 hemilaminectomy and foraminotomy to expose the C7 root from its origin to the spinal nerve bifurcation. In 6 patients, the dural cuff supposed to contain the ganglion was resected en bloc; and in 9 patients, the ganglion was obtained through a longitudinal incision of the dural cuff and microsurgical dissection from the ventral and dorsal roots and radicular arteries. All ganglia were histopathologically examined. Results: No ganglion was found in the dural cuff in 2 patients submitted to en bloc removal, and the ganglion was removed in all patients who underwent microsurgical dissection. All but 2 patients that had ganglion examination presented a neuronopathy of nerve cell loss, 3 with mononuclear inflammatory infiltrate. These patients underwent immunosuppressive therapy, and 2 of them presented clinical improvement. No surgical complications were observed. Conclusions: Microsurgical dorsal root ganglionectomy for diagnosing inflammatory sensory ganglionopathies was effective and safe. Although safe, en bloc resection of the proximal dural cuff was not effective for this purpose. (c) 2008 Published by Elsevier Inc.

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Rat airways exposure to Staphylococcal enterotoxin A (SEA) and B (SEB) induces marked neutrophil influx. Since sensory neuropeptides play important roles in cell infiltration, in this study we have investigated its contribution in triggering SEA- and SEB-induced pulmonary neutrophil infiltration. Male Wistar rats were exposed intratracheally with SEA (3 ng/trachea) or SEB (250 ng/trachea). Animals received different in vivo pretreatments, after which the neutrophil counts and levels of substance P and IL-1 in bronchoalveolar lavage fluid were evaluated. Alveolar macrophages and peritoneal mast cells were incubated with SEA and SEB to determine the IL-1 and TNF-alpha levels. Capsaicin pretreatment significantly reduced SEA- and SEB-induced neutrophil influx in bronchoalveolar lavage fluid, but this treatment was more effective to reduce SEA responses. Treatments with SR140333 (tachykinin NK(1) receptor antagonist) and SR48968 (tachykinin NK(2) receptor antagonist) decreased SEA-induced neutrophil influx, whereas SEB-induced responses were inhibited by SR140333 only. Cyproheptadine (histamine/5-hydroxytriptamine receptor antagonist) and MD 7222 (5-HT(3) receptor antagonist) reduced SEA- and SEB-induced neutrophil influx. The substance P and IL-1 levels in bronchoalveolar lavage fluid of SEA-exposed rats were significantly hi.-her than SEB. In addition, SEA (but not SEB) significantly released mast cell TNF-alpha. Increased production of TNF-alpha and IL-1 in alveolar macrophages was observed in response to SEA and SEB. In conclusion, sensory neuropeptides contribute significantly to SEA- and SEB-induced pulmonary neutrophil recruitment, but SEA requires in a higher extent the airways sensory innervation, and participation of mast cells and alveolar macrophage products. (C) 2009 Elsevier B.V. All rights reserved.

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Background and purpose: Hereditary sensory and autonomic neuropathy ( HSAN) type V is a very rare disorder. It is characterized by the absence of thermal and mechanical pain perception caused by decreased number of small diameter neurons in peripheral nerves. Recent genetic studies have pointed out the aetiological role of nerve growth factor beta, which is also involved in the development of the autonomic nervous system and cholinergic pathways in the brain. HSAN type V is usually reported not to cause mental retardation or cognitive decline. However, a structured assessment of the cognitive pro. le of these patients has never been made. Methods and results: We performed a throughout evaluation of four HSAN type V patients and compared their performance with 37 normal individuals. Our patients showed no cognitive deficits, not even mild ones. Discussion and Conclusions: Although newer mutations on this and related disorders are continuously described, their clinical characterization has been restricted to the peripheral aspects of these conditions. A broader characterization of this rare disorder may contribute to better understand the mechanisms of the nociceptive and cognitive aspects of pain.

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The objective of this research was to evaluate the effects of 2 levels of raw milk somatic cell count (SCC) on the composition of Prato cheese and on the microbiological and sensory changes of Prato cheese throughout ripening. Two groups of dairy cows were selected to obtain low-SCC (<200,000 cells/mL) and high-SCC (>700,000 cells/mL) milks, which were used to manufacture 2 vats of cheese. The pasteurized milk was evaluated according to the pH, total solids, fat, total protein, lactose, standard plate count, coliforms at 45 degrees C, and Salmonella spp. The cheese composition was evaluated 2 d after manufacture. Lactic acid bacteria, psychrotrophic bacteria, and yeast and mold counts were carried out after 3, 9, 16, 32, and 51 d of storage. Salmonella spp., Listeria monocytogenes, and coagulase-positive Staphylococcus counts were carried out after 3, 32, and 51 d of storage. A 2 x 5 factorial design with 4 replications was performed. Sensory evaluation of the cheeses from low- and high-SCC milks was carried out for overall acceptance by using a 9-point hedonic scale after 8, 22, 35, 50, and 63 d of storage. The somatic cell levels used did not affect the total protein and salt: moisture contents of the cheeses. The pH and moisture content were higher and the clotting time was longer for cheeses from high-SCC milk. Both cheeses presented the absence of Salmonella spp. and L. monocytogenes, and the coagulase-positive Staphylococcus count was below 1 x 10(2) cfu/g throughout the storage time. The lactic acid bacteria count decreased significantly during the storage time for the cheeses from both low- and high-SCC milks, but at a faster rate for the cheese from high-SCC milk. Cheeses from high-SCC milk presented lower psychrotrophic bacteria counts and higher yeast and mold counts than cheeses from low- SCC milk. Cheeses from low- SCC milk showed better overall acceptance by the consumers. The lower overall acceptance of the cheeses from high-SCC milk may be associated with texture and flavor defects, probably caused by the higher proteolysis of these cheeses.

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Prostate growth and physiology are regulated by steroid hormones and modulated by multiple endocrine factors We investigated the action of insulin on the tissue organization and kinetics of epithelial cells in the rat ventral prostate (VP) in response to castration up to 120 hours after surgery by using an acute protocol of alloxan induced diabetes Diabetes caused a reduction in volume density (Vv(o)/) and volume of the epithelium The effects of castration on the epithelium were accelerated in the diabetic animals as determined by changes in V(o)/, and volume The smooth muscle cells became atrophic and apparently relaxed in response to castration in contrast to the spinous aspect observed in nondiabetic castrated rats Counting of apoptotic nuclei in the epithelium showed the classical apoptosis peak at 72 hours in nondiabetic rats and an advance of the apoptosis peak to 48 hours after castration in diabetic rats Insulin restored the time of the peak to 72 hours These results were confirmed after immunostaining for cleaved caspase 3 and suggest a survival and antiapoptotic effect on VP epithelial cells in both the presence and absence of androgen stimulation This idea is supported by the observation that insulin also reduced the overall rate of apoptosis at all experimental points analyzed before and after castration

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In this study the main question investigated was the number and size of both binucleate and mononucleate superior cervical ganglion (SCG) neurons and, whether post-natal development would affect these parameters. Twenty left SCGs from 20 male pacas were used. Four different ages were investigated, that is newborn (4 days), young (45 days), adult (2 years), and aged animals (7 years). By using design-based stereo-logical methods, that is the Cavalieri principle and a physical disector combined with serial sectioning, the total volume of ganglion and total number of mononucleate and binucleate neurons were estimated. Furthermore, the mean perikaryal (somal) volume of mononucleate and binucleate neurons was estimated using the vertical nucleator. The main findings of this study were a 154% increase in the SCG volume, a 95% increase in the total number of mononucleate SCG neurons and a 50% increase in the total volume of SCG neurons. In conclusion, apart from neuron number, different adaptive mechanisms may coexist in the autonomic nervous system to guarantee a functional homeostasis during ageing, which is not always associated with neuron losses. Anat Rec, 292:966-975, 2009. (C) 2009 Wiley-Liss, Inc.

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The maned wolf (Chrysocyon brachyurus) is the largest canid in South America, weighing up to 30 kg, and exhibits an omnivorous diet based on fruits and small vertebrates. Maned wolves are considered to live in monogamous pairs defending a common territory, with mates living a largely solitary life, but these conclusions come from few studies with small samples. We captured maned wolves in Emas National Park, central Brazil, and monitored their use of space using radiotelemetry. Home-range size and overlap of 45 adults, and interactions between members of 5 pairs, were investigated. Home-range sizes of resident adults averaged 80.18 km(2) using the fixed kernel with 95% of the locations, and averaged 13.78 km(2) with 50% of the locations. Overlap of 95% ranges between male-male, female-female, or mixed dyads was similar, approximately 0.20, whereas 50% ranges of maned wolves showed less overlap overall but more tolerance for overlap with the opposite sex. Members of a pair were located alone more often than together, and even when located simultaneously maintained a mean distance of >0.5 km apart, independent of time of day. Results are in agreement with a spatial organization based on monogamous mating pairs with little intrapair sociality, but the latter needs to be investigated in more detail.

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The architectonic features of the thalamic ventrobasal complex (Vb) of two species of Megachiropteran (Grey-headed flying fox, Pteropus poliocephalus, and the Eastern tube-nosed bat, Nyctimene robinsoni) are compared with those of a Microchiropteran (Australian ghost bat, Macroderma gigas). The somatosensory system was chosen for comparison as it represents a sensory system that has undergone analogous modifications in both Chiropteran lineages (the evolution of the wing). The components of Vb were examined as there are taxon-specific features in this region of the brain. Within the Megachiropteran Vb, four subnuclei were recognized: the ventral posterior medial (VPM), the ventral posterior lateral (VPL), the ventral posterior inferior (VPI), and the basal ventral medial (VMb). In the ghost bat only VPM and VPL were identified with certainty. No VPI was evident in the ghost bat, however a putative VMb was observed. Vb of the ghost bat also lacked the arcuate lamina, which distinguishes VPM from VPL in the Megachiropterans and many other mammals. These taxon-specific differences lend support to the proposal that the order Chiroptera has a diphyletic origin.

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The present study investigates the somatotopic representation in the somatosensory thalamus of a megachiropteran bat. Using standard microelectrode mapping techniques, representational maps were generated for the ventrobasal (Vb) and posterior (Po) thalamic complexes of the Grey-headed flying fox. Anatomical tracing from neocortical injections provided additional data confirming the somatotopy found physiologically. A full representation of the body surface innervated by the trigeminal and spinal nerves was found. However, in contrast with other mammals, the representations of the forelimb and adjacent thoracic trunk within the thalamus were inverted. This means that the distal portions of the wing membrane and the tips of the digits were represented dorsally in Vb, and the thoracic trunk was represented ventrally In Po the digit tips were represented in the ventral most portion and the thoracic trunk in the dorsal portion of the nucleus. These results are discussed in relation to similarities of megachiropteran somatosensory thalamic nuclei to those of other mammalian species and in relation to the formation of thalamic somatotopic maps and fiber sorting.

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Spontaneous and tone-evoked changes in light reflectance were recorded from primary auditory cortex (A1) of anesthetized cats (barbiturate induction, ketamine maintenance). Spontaneous 0.1-Hz oscillations of reflectance of 540- and 690-nm light were recorded in quiet. Stimulation with tone pips evoked localized reflectance decreases at 540 nm in 3/10 cats. The distribution of patches activated by tones of different frequencies reflected the known tonotopic organization of auditory cortex. Stimulus-evoked reflectance changes at 690 nm were observed in 9/10 cats but lacked stimulus-dependent topography. In two experiments, stimulus-evoked optical signals at 540 nm were compared with multiunit responses to the same stimuli recorded at multiple sites. A significant correlation (P < 0.05) between magnitude of reflectance decrease and multiunit response strength was evident in only one of five stimulus conditions in each experiment. There was no significant correlation when data were pooled across all stimulus conditions in either experiment. In one experiment, the spatial distribution of activated patches, evident in records of spontaneous activity at 540 nm, was similar to that of patches activated by tonal stimuli. These results suggest that local cerebral blood volume changes reflect the gross tonotopic organization of A1 but are not restricted to the sites of spiking neurons.

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The extrastriate cortex near the dorsal midline has been described as part of an 'express' pathway that provides visual input to the premotor cortex. This pathway is considered important for the integration of sensory information about the visual field periphery and the skeletomotor system, especially in relation to the control of arm movements. However, a better understanding of the functional contributions of different parts of this complex has been hampered by the lack of data on the extent and boundaries of its constituent visual areas. Recent studies in macaques have provided the first detailed view of the topographical organization of this region in Old World monkeys. Despite differences in nomenclature, a comparison of the visuotopic organization, myeloarchitecture and connections of the relevant visual areas with those previously studied in New World monkeys reveals a remarkable degree of similarity and helps to clarify the subdivision of function between different areas of the dorsomedial complex. A caudal visual area, named DM or V6, appears to be important for the detection of coherent patterns of movement across wide regions of the visual field, such as those induced during self-motion. A rostral area, named M or V6A, is more directly involved with visuomotor integration. This area receives projections both from DM/V6 and from a separate motion analysis channel, centred on the middle temporal visual area (or V5), which detects the movement of objects in extrapersonal space. These results support the suggestion, made earlier on the basis of more fragmentary evidence, that the areas rostral to the second visual area in dorsal cortex are homologous in all simian primates. Moreover, they emphasize the importance of determining the anatomical organization of the cortex as a prerequisite for elucidating the function of different cortical areas.

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We describe the genomic organization of a recently identified CC chemokine, MIP3 alpha /CCL20 (HGMW-approved symbol SCYA20). The MIP-3 alpha /CCL20 gene was cloned and sequenced, revealing a four exon, three intron structure, and was localized by FISK analysis to 2q35-q36. Two distinct cDNAs were identified, encoding two forms of MIP-3 alpha /CCL20, Ala MLP-3 alpha /CCL20 and Ser MIP-3 alpha /CCL20, that differ by one amino acid at the predicted signal peptide cleavage site. Examination of the sequence around the boundary of intron 1 and exon 2 showed that use of alternative splice acceptor sites could give rise to Ata MIP-3 alpha /CCL20 or Ser MIP-3 alpha /CCL20. Both forms of MIP-3cr/CCL20 were chemically synthesized and tested for biological activity. Both flu antigen plus IL-a-activated CD4(+) and CD8(+) T lymphoblasts and cord blood-derived dendritic cells responded to Ser and Ala MIP-3 alpha /CCL20. T lymphocytes exposed only to IL-2 responded inconsistently, while no response was detected in naive T lymphocytes, monocytes, or neutrophils. The biological activity of Ser MIP-3 alpha /CCL20 and Ala MIP-3 alpha /CCL20 and the tissue-specific preference of different splice acceptor sites are not yet known. (C) 2001 Academic Press.