965 resultados para Middle Temporal Area


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The distribution and density of a population of the narrowback mud crab Panopeus americanus were evaluated, with emphasis on the different developmental stages (juveniles and adults) and sexes. Specimens were collected in a remnant human-impacted mangrove at Araca on the northern coast of Sao Paulo, Brazil, at two-month intervals from January through July 2006, using 1m x 1m sample plots randomly distributed in the intertidal zone. The population was abundant, with a mean density of 14.3 +/- 9.3 individuals/m(2). Larger individuals were more abundant in the upper and middle intertidal zones, whereas smaller crabs were predominant in the lower intertidal and thus remained submerged longer. Males and juveniles were homogeneously distributed. Females preferred regions farther from the waterline. A clustered distribution pattern suggested gregarious behaviour and settling of juveniles in the vicinity of the adults` habitats, in an adaptive process as a function of tidal rhythms.

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The prevalence of the parasite Aporobopyrus curtatus in Petrolisthes armatus from southern Brazil was determined, and the effect the parasite had on host reproduction was evaluated. Of all 775 crabs sampled in Araca region from March 2005 to July 2006, 3.2% presented bopyrid parasites. All the parasitized individuals had one branchial chamber occupied by two mature parasites, with no preference for the right or left chamber. Male and female hosts were infested in equal proportions. Parasitized juveniles, large individuals and ovigerous females were not found in our study. The absence of parasitized ovigerous females seems to be insufficient evidence to support the hypothesis of parasitic castration and would require a histological study to confirm their reproductive death. The percentage of infestation observed in our study (3.1%) is lower than the one found in other studies and it could indicate the existence of factor(s) regulating the density of A. curtatus in the Araca region. At least in this population, the low but constant presence of the bopyrid A. curtatus population did not appear to have a negative effect on the porcellanid population, and parasitized individuals did not play a significant role in the natural history of P. armatus.

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The taxonomic composition and diversity of assemblages of Ephemeroptera nymphs of four lotic environments in the central region of State of Rio Grande do Sul, a subtropical area in southern Brazil, were evaluated. Samplings were done monthly, with a Surber sampler, from June 2001 to May 2002, in the Jacui River and three of its tributaries. The total number of nymphs collected in the four sampling sites was 11,007 in five families and 19 genera, of these, 11 are new records for the State. The highest diversity occurred in Point 4 (H` = 2.41) and the lowest in Point 2 (H` = 1.69). Point 4 had the highest environmental stability, conservation of the riparian vegetation and the lowest anthropic impact, while Point 2 presented a large environmental simplification due to a direct anthropic influence ( e. g. domestic sewerage, trampling by cattle). The diversity of nymphs observed in the total area is high, compared to the estimated maximum theoretical diversity; a result of the high evenness and richness recorded. Rarefaction curves, calculated for a sample of 1,018 specimens, showed a similar expectation of richness for the four sampling sites. This result seems to be associated with the overall environmental homogeneity of the region caused by long-term alterations ( land use and deforestation). In summary, higher diversity of Ephemeroptera nymph assemblages seems to be associated with habitat complexity, a good vegetation cover and a lower anthropic influence.

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The present study aimed to determine the richness, occurrence constancy, reproductive modes. standard of abundance distribution, season of vocalization and to test correlation among climatic variables and activity of vocalization of anurans in a region of the Pampa Biome, Santa Maria, Rio Grande do Sul State. During the period of Novernber/2001 to October/2002 monthly collections were carried out utilizing the `survey at breeding site` method and examination of specimens kept in the Colecao Herpetologica do Setor de Zoologia da Universidade Federal de Santa Maria (ZUFSM). Tire Occurrence of 25 species of anurans was recorded. The anurofauna recorded represents 30% of the species known to Occur in Rio Grande do Sul, and comprises species generally associated with grasslands in this state and neighboring countries. Four reproductive modes were recorded: mode 1 (14 species: 58.3%) mode 11 and 30 (9 species` 37.5%) and mode 24 (1 species; 4.2%). The low diversification of reproductive modes is likely related to the homogeneity of the grassland habitat. Most species were constant or accessory in the Study area and the species abundance distribution patterns fit in the Broken Stick and Log-normal models. characterized by homogeneity of species abundance distribution. Most species showed great plasticity in habitat. but few were plastic in vocalization sites use. There was a weak positive correlation between species richness and precipitation. There was also a weak positive correlation between the abundance of species calling activity and maximum average temperatures. These correlations indicated that, in the study area. the abundance of calling males is more affected by the temperature, and species richness is more affected by precipitation, despite the fact that significantly higher species richness occurs during the hottest period of the year. These results showed that the climatological variables examined were not enough to explain the seasonal occurrence of species, thus the influence of other environmental variables merit to be tested in future studies.

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OBJECTIVE: We present observations of the anatomy of the sylvian fissure region and their clinical application in neuroimaging, microsurgery for middle cerebral artery aneurysms and insular lesions, frontobasal resections, and epilepsy Surgery. METHODS: Sixty adult cadaveric hemispheres and 12 adult cadaveric heads were studied after perfusion of the arteries and veins with colored latex. The anatomic information was applied in more than 200 microsurgeries in and around the sylvian fissure region in the past 15 years. RESULTS: The sylvian fissure extends from the basal to the lateral surface of the brain and presents 2 compartments on each surface, I superficial (temporal stem and its ramii) and 1 deep (anterior and lateral operculoinsular compartments). The temporal operculum is in opposition to the frontal and parietal opercula (planum polare versus inferior frontal and precentral gyri, Heschl`s versus postcentral gyri, planum temporale versus supramarginal gyrus). The inferior frontal, precentral, and postcentral gyri cover the anterior, middle, and posterior thirds of the lateral surface of the insula, respectively. The pars triangularis covers the apex of the insula, located immediately distal to the genu of the middle cerebral artery. The clinical application of the anatomic information presented in this article is in angiography, middle cerebral artery aneurysm surgery, insular resection, frontobasal resection, and amygdalohippocampectomy, and hemispherotomy. CONCLUSION: The anatomic relationships of the sylvian fissure region can be helpful in preoperative planning and can serve as reliable intraoperative navigation landmarks in microsurgery involving that region.

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Objetive: To evaluate the effects of conjugated equine estrogens (CEE) on the pilocarpine-induced epilepsy in rats. Study design: 40 female rats were divided into: GPC (positive control) presented ""status epilepticus"" (SE) induced by pilocarpine; GOC(ovariectomized control) only castrated; GNC (negative control) received only saline solution; GPE received pilocarpine, presented SE, castrated and received 50 mu g/kg CEE treatment; GPV received pilocarpine, castrated and received propylene glycol (vehicle). The animals were monitored by a video system. At the end of observation, the brains removed for later histologic analysis using Neo-Timm and Nissl methods. Results: The GPE presented a reduction in number of seizures compared to GPV. The Neo-Timm analysis showed that GPV had greater sprouting of mossy fibers, with a denser band in the area of the dentate gyrus hilum compared to GPE. On Nissl staining, GPE showed evident neuronal loss in the CA3 area. GPV presented loss in CA1 and dentate gyrus. Conclusion: Estrogen may have a protecting effect on the central nervous system. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: This is a clinical study of our experience using pedicle perforator flaps to cover skin defects in the middle and distal segment of the leg. Design: Prospective study. Setting: University hospital. Patients/Intervention: Twenty-four patients underwent treatment of a skin defect in the middle or distal segment of the leg by means of pedicled flaps based on perforating arteries. The perforating arteries were located before the operation by means of echo-Doppler examination. The flaps were planned in propeller fashion (21 cases) and as advancement (three cases). Main Outcome Measurements: The results were evaluated according the origin of perforator flap, size of the flap, and donor area and viability of the flap. The success rate of the echo-Doppler to identify the location of perforator vessel was also evaluated. Results: In nine cases, the perforating vessels originated from the fibular artery, in 10 the posterior tibial artery, and in five the anterior tibial artery. The mean size of the flaps was 5 cm in width by 12 cm in length. The success rate using an echo-Doppler was 87%. The flaps were fully viable in 20 cases and partially viable in four cases. Conclusion: On the basis of these results, it is concluded that perforating flaps are a good choice of treatment for skin losses, especially in the distal segment of the leg, and could be an alternative option for the use of free microsurgical flaps.

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Cognitive deficits are a key feature of recent-onset psychosis, but there is no consensus on whether such deficits are generalized or confined to specific domains. Besides, it is unclear whether cognitive deficits: a) are found in psychotic patients in samples from outside high-income countries; and b) whether they progress uniformly over time in schizophrenia and affective psychoses. We applied 12 tests organized into eight cognitive domains, comparing psychosis patients (n = 56, time from initial contact = 677.95+/-183.27 days) versus healthy controls (n = 70) recruited from the same area of Sao Paulo, Brazil. Longitudinal comparisons (digit span and verbal fluency) were conducted between a previous assessment of the subjects carried out at their psychosis onset, and the current follow-up evaluation. Psychosis patients differed significantly from controls on five domains, most prominently on verbal memory. Cognitive deficits remained detectable in separate comparisons of the schizophrenia subgroup and, to a lesser extent, the affective psychosis subjects against controls. Longitudinal comparisons indicated significant improvement in schizophrenia, affective psychoses, and control subjects, with no significant group-by-time interactions. Our results reinforce the view that there are generalized cognitive deficits in association with recent-onset psychoses, particularly of non-affective nature, which persist over time. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

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Background: HTLV-1/2 diagnosis in high-risk populations from Sao Paulo, Brazil has been problematic due a high proportion of seroindeterminate results. Objectives: To confirm and extend previous findings regarding HTLV-1/2 diagnosis in this geographic area. Study design: Sera from 2312 patients were tested for HTLV-1/2 antibodies using enzyme immunoassay (EIA) and Western blot (WB) analysis. Patients were from AIDS Reference Centers (Group 1; 1393 patients) and HTLV out-patient clinics (Group 11; 919 patients). Results were analyzed according to patients` age, gender, and clinic type. Results: HTLV-1 and HTLV-2 were detected in both groups. Among seropositive females, HTLV-2 was slightly more common in Group 1 (54.5%), while HTLV-1 prevailed in Group II (73.9%). Males from Group II had a higher percentage of HTLV-seroindeterminate results. No correlation between HTLV serological results and age was detected. Temporal analyses disclosed a high number of HTLV-seroindeterminate samples, and a large spectrum of indeterminate WB profiles. GD21 and/or rgp46-II bands were detected in 34.6% of sera from Group 1, and a p24 or p19 band was detected in 35.3% of sera from Group II. Conclusions: High rates of HTLV-indeterminate serological patterns during temporal analyses were confirmed in high-risk populations from Sao Paulo, Brazil. (c) 2008 Elsevier B.V. All rights reserved.

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Object. The goal of this paper is to analyze the extension and relationships of glomus jugulare tumor with the temporal bone and the results of its surgical treatment aiming at preservation of the facial nerve. Based on the tumor extension and its relationships with the facial nerve, new criteria to be used in the selection of different surgical approaches are proposed. Methods. Between December 1997 and December 2007, 34 patients (22 female and 12 male) with glomus jugulare tumors were treated. Their mean age was 48 years. The mean follow-up was 52.5 months. Clinical findings included hearing loss in 88%, swallowing disturbance in 50%, and facial nerve palsy in 41%. Magnetic resonance imaging demonstrated a mass in the jugular foramen in all cases, a mass in the middle ear in 97%, a cervical mass in 85%, and an intradural mass in 41%. The tumor was supplied by the external carotid artery in all cases, the internal carotid artery in 44%, and the vertebral artery in 32%. Preoperative embolization was performed in 15 cases. The approach was tailored to each patient, and 4 types of approaches were designed. The infralabyrinthine retrofacial approach (Type A) was used in 32.5%; infralabyrinthine pre- and retrofacial approach without occlusion of the external acoustic meatus (Type B) in 20.5%; infralabyrinthine pre- and retrofacial approach with occlusion of the external acoustic meatus (Type C) in 41 W. and the infralabyrinthine approach with transposition of the facial nerve and removal of the middle ear structures (Type D) in 6% of the patients. Results. Radical removal was achieved in 91% of the cases and partial removal in 9%. Among 20 patients without preoperative facial nerve dysfunction, the nerve was kept in anatomical position in 19 (95%), and facial nerve function was normal during the immediate postoperative period in 17 (85%). Six patients (17.6%) had a new lower cranial nerve deficit, but recovery of swallowing function was adequate in all cases. Voice disturbance remained in all 6 cases. Cerebrospinal fluid leakage occurred in 6 patients (17.6%), with no need for reoperation in any of them. One patient died in the postoperative period due to pulmonary complications. The global recovery, based on the Karnofsky Performance Scale (KPS), was 100% in 15% of the patients, 90% in 45%, 80% in 33%, and 70% in 6%. Conclusions. Radical removal of glomus jugulare tumor can be achieved without anterior transposition of the facial nerve. The extension of dissection, however, should be tailored to each case based on tumor blood supply, preoperative symptoms, and tumor extension. The operative field provided by the retrofacial infralabyrinthine approach, or the pre- and retrofacial approaches. with or without Closure of the external acoustic meatus, allows a wide exposure of the jugular foramen area. Global functional recovery based on the KPS is acceptable in 94% of the patients. (DOI: 10.3171/2008.10.JNS08612)

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The aims of this study were to characterize the spatial distribution of neurodegeneration after status epilepticus (SE) induced by either systemic (S) or intrahippocampal (H) injection of pilocarpine (PILO), two models of temporal lobe epilepsy (TLE), using FluoroJade (FJ) histochemistry, and to evaluate the kinetics of FJ staining in the H-PILO model. Therefore, we measured the severity of behavioral seizures during both types of SE and also evaluated the FJ staining pattern at 12, 24, and 168 h (7 days) after the H-PILO insult. We found that the amount of FJ-positive (FJ+) area was greater in SE induced by S-PILO as compared to SE induced by H-PILO. After SE induced by H-PILO, we found more FJ+ cells in the hilus of the dentate gyrus (DG) at 12 h, in CA3 at 24 h, and in CA1 at 168 h. We found also no correlation between seizure severity and the number of FJ+ cells in the hippocampus. Co-localization studies of FJ+ cells with either neuronal-specific nuclear protein (NeuN) or glial fibrillary acidic protein (GFAP) labeling 24 h after H-PILO demonstrated spatially selective neurodegeneration. Double labeling with FJ and parvalbumin (PV) showed both FJ+/PV+ and FJ+/PV- cells in hippocampus and entorhinal cortex, among other areas. The current data indicate that FJ+ areas are differentially distributed in the two TLE models and that these areas are greater in the S-PILO than in the H-PILO model. There is also a selective kinetics of FJ+ cells in the hippocampus after SE induced by H-PILO, with no association with the severity of seizures, probably as a consequence of the extra-hippocampal damage. These data point to SE induced by H-PILO as a low-mortality model of TLE, with regional spatial and temporal patterns of FJ staining. (C) 2010 Elsevier B.V. All rights reserved.

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To analyse the gutta-percha filled area of C-shaped molar teeth root filled with the modified MicroSeal technique with reference to the radiographic features and the C-shaped canal configuration. Twenty-three mandibular second molar teeth with C-shaped roots were classified according to their radiographic features as: type I - merging, type II - symmetrical and type III - asymmetrical. The canals were root filled using a modified technique of the MicroSeal system. Horizontal sections at intervals of 600 mu m were made 1 mm from the apex to the subpulpal floor level. The percentage of gutta-percha area from the apical, middle and coronal levels of the radiographic types was analysed using the Kruskal-Wallis test. Complementary analysis of the C-shaped canal configurations (C1, C2 and C3) determined from cross-sections from the apical third was performed in a similar way. No significant differences were found between the radiographic types in terms of the percentage of gutta-percha area at any level (P > 0.05): apical third, type I: 77.04%, II: 70.48% and III: 77.13%, middle third, type I: 95.72%, II: 93.17%, III: 91.13% and coronal level, type I: 98.30%, II: 98.25%, III: 97.14%. Overall, the percentage of the filling material was lower in the apical third (P < 0.05). No significant differences were found between the C-shaped canal configurations apically; C1: 72.64%, C2: 79.62%, C3: 73.51% (P > 0.05). The percentage of area filled with gutta-percha was similar in the three radiographic types and canal configuration categories of C-shaped molars. These results show the difficulty of achieving predictable filling of the root canal system when this anatomical variation exists. In general, the apical third was less completely filled.

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Early-life events may induce alterations in neuronal function in adulthood. A crucial aspect in studying long-lasting effects induced by environmental interventions imposed to the animal several weeks before is finding a stable change that could be causally related to the phenotype observed in adulthood. In order to explain an adult trait, it seems necessary to look back to early life and establish a temporal line between events. The neonatal handling procedure is an experimental tool to analyze the long-lasting impact of early-life events. Aside from the neuroendocrine response to stress, neonatal handling also alters the functionality of the hypothalamus-pituitary-gonad (HPG) axis. Reductions in ovulation and surge of the luteinizing hormone (LH) on the proestrous day were shown in female rats. Considering the importance of the medial preoptic area (MPA) for the control of ovulation, the present study aimed to verify the effects of neonatal handling on the numerical density and cell size in the MPA in 11-day-old and 90-day-old female rats. Cellular proliferation was also assessed using BrdU (5-bromo-2`-deoxyuridine) in 11-day-old pups. Results showed that neonatal handling induces a stable reduction in the number of cells and in the size of the cell soma, which were lower in handled females than in nonhandled ones at both ages. Cellular proliferation in the MPA was also reduced 24 h after the last manipulation. The repeated mother-infant disruption imposed by the handling procedure ""lesioned"" the MPA. The dysfunction in the ovulation mechanisms induced by the handling procedure could be related to that neuronal loss. The study also illustrates the impact of an environmental intervention on the development of the brain. (C) 2008 Elsevier B.V. All rights reserved

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Immunocytochemical techniques were used to examine the distribution of neurons immunoreactive (-ir) for nitric oxide synthase (nNOS), somatostatin (SOM), neuropeptide Y (NPY), parvalbumin (PV), calbindin (CB) and calretinin (CH), in the inferotemporal gyros (Brodmann's area 21) of the human neocortex. Neurons that colocalized either nNOS or SOM with PV, CB or CR were also identified by double-labeling techniques. Furthermore, glutamate receptor subunit profiles (GluR1, GluR2/3, GluR2/4, GluR5/6/7 and NMDAR1) were also determined for these cells. The number and distribution of cells containing nNOS, SOM, NPY, PV, CB or CR differed for each antigen. In addition, distinct subpopulations of neurons displayed different degrees of colocalization of these antigens depending on which antigens were compared. Moreover, cells that contained nNOS, SOM, NPY, PV, GB or CR expressed different receptor subunit profiles. These results show that specific subpopulations of neurochemically identified nonpyramidal cells may be activated via different receptor subtypes. As these different subpopulations of cells project to specific regions of pyramidal calls, facilitation of subsets of these cells via different receptor subunits may activate different inhibitory circuits. Thus, various distinct, but overlapping, inhibitory circuits may act in concert in the modulation of normal cortical function, plasticity and disease.

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The basal dendritic arbors of over 500-layer III pyramidal neurones of the macaque cortex were compared by fractal analyses, which provides a measure of the space filling (or branching pattern) of dendritic arbors. Fractal values (D) of individual cells were compared between the cytochrome oxidase (CO)-rich blobs and CO-poor interblobs, of middle and upper layer III, and between sublaminae, in the primary visual area (Vi). These data were compared with those in the CO compartments in the second visual area (V2), and seven other extrastriate cortical areas. (V4, MT, LIP, 7a, TEO, TE and STP). There were significant differences in the fractal dimensions, and therefore the dendritic branching patterns, of cells in striate and extrastriate areas. Of the 55 possible pairwise comparisons of fractal dimension of neurones in different cortical areas (or CO compartments), 39 proved to be significantly different. The markedly different morphologies of pyramidal cells in the different cortical areas may be one of the features that determine the functional signatures of these cells by influencing the number of inputs received by, and propagation of potentials through, their dendritic arbors.