7 resultados para Innervation
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Patients with cleft lip and palate usually present dental anomalies of number, shape, structure and position in the cleft area and the general dentist is frequently asked to restore or extract those teeth. Considering that several anatomic variations are expected in teeth adjacent to cleft areas and that knowledge of these variations by general dentists is required for optimal treatment, the objectives of this paper are: 1) to describe changes in the innervation pattern of anterior teeth and soft tissue caused by the presence of a cleft, 2) to describe a local anesthetic procedure in unilateral and bilateral clefts, and 3) to provide recommendations to improve anesthetic procedures in patients with cleft lip and palate. The cases of 2 patients are presented: one with complete unilateral cleft lip and palate, and the other with complete bilateral cleft lip and palate. The patients underwent local anesthesia in the cleft area in order to extract teeth with poor bone support. The modified anesthetic procedure, respecting the altered course of nerves in the cleft maxilla and soft tissue alterations at the cleft site, was accomplished successfully and the tooth extraction was performed with no pain to the patients. General dentists should be aware of the anatomic variations in nerve courses in the cleft area to offer high quality treatment to patients with cleft lip and palate.
Resumo:
Objective: To test the hypothesis that the extraocular muscles (EOMs) of patients with infantile nystagmus have muscular and innervational adaptations that may have a role in the involuntary oscillations of the eyes. Methods: Specimens of EOMs from 10 patients with infantile nystagmus and postmortem specimens from 10 control subjects were prepared for histologic examination. The following variables were quantified: mean myofiber cross-sectional area, myofiber central nucleation, myelinated nerve density, nerve fiber density, and neuromuscular junction density. Results: In contrast to control EOMs, infantile nystagmus EOMs had significantly more centrally nucleated myofibers, consistent with cycles of degeneration and regeneration. The EOMs of patients with nystagmus also had a greater degree of heterogeneity in myofiber size than did those of controls, with no difference in mean myofiber cross-sectional area. Mean myelinated nerve density, nerve fiber density, and neuromuscular junction density were also significantly decreased in infantile nystagmus EOMs. Conclusions: The EOMs of patients with infantile nystagmus displayed a distinct hypoinnervated phenotype. This represents the first quantification of changes in central nucleation and myofiber size heterogeneity, as well as decreased myelinated nerve, nerve fiber, and neuromuscular junction density. These results suggest that deficits in motor innervation are a potential basis for the primary loss of motor control.
Resumo:
The aim of this study was to identify immunoreactive neuropeptide Y (NPY) and calcitonin gene-related peptide (CGRP) neurons in the autonomic and sensory ganglia, specifically neurons that innervate the rat temporomandibular joint (TMJ). A possible variation between the percentages of these neurons in acute and chronic phases of carrageenan-induced arthritis was examined. Retrograde neuronal tracing was combined with indirect immunofluorescence to identify NPY-immuno-reactive (NPY-IR) and CGRP-immunoreactive (CGRP-IR) neurons that send nerve fibers to the normal and arthritic temporomandibular joint. In normal joints, NPY-IR neurons constitute 78 +/- 3%, 77 +/- 6% and 10 +/- 4% of double-labeled nucleated neuronal profile originated from the superior cervical, stellate and otic ganglia, respectively. These percentages in the sympathetic ganglia were significantly decreased in acute (58 +/- 2% for superior cervical ganglion and 58 +/- 8% for stellate ganglion) and chronic (60 +/- 2% for superior cervical ganglion and 59 +/- 15% for stellate ganglion) phases of arthritis, while in the otic ganglion these percentages were significantly increased to 19 +/- 5% and 13 +/- 3%, respectively. In the trigeminal ganglion, CGRP-IR neurons innervating the joint significantly increased from 31 +/- 3% in normal animals to 54 +/- 2% and 49 +/- 3% in the acute and chronic phases of arthritis, respectively. It can be concluded that NPY neurons that send nerve fibers to the rat temporomandibular joint are located mainly in the superior cervical, stellate and otic ganglia. Acute and chronic phases of carrageenan-induced arthritis lead to an increase in the percentage of NPY-IR parasympathetic and CGRP-IR sensory neurons and to a decrease in the percentage of NPY-IR sympathetic neurons related to TMJ innervation.
Resumo:
O músculo diafragma, encontrado apenas nos mamíferos, é o principal músculo no processo respiratório, servindo de fronteira entre as cavidades torácica e abdominal. Sua importância também ganha destaque em pesquisas realizadas no âmbito dos enxertos, empregando-se diversos tipos de membranas biológicas para o reparo de defeitos diafragmáticos, os quais podem gerar hérnias diafragmáticas. Apesar de muitos estudos já conduzidos para com os primatas não humanos, especialmente no que tange a espécie do novo mundo Callithrix jacchus (Sagui-de-tufo-branco), oriundo do nordeste brasileiro, as pesquisas envolvendo o uso do diafragma em tal espécie é inexistente. Deste modo objetivou-se caracterizar a morfologia e a biometria do diafragma na espécie Callithrix jacchus de ambos os sexos, analisando possíveis divergências estruturais entre machos e fêmeas. Para tal foram utilizados quatros animais, 2 machos e 2 fêmeas, adultos, que vieram a óbito por causas naturais, provenientes de um criadouro comercial. Após fixação em solução de formaldeído 10% os animais foram devidamente dissecados para fotodocumentação e em seguida o diafragma coletado para efetuação da biometria (comprimento e largura) com o uso de um paquímetro e para o processamento histológico por meio da coloração de hematoxilina-eosina e tricrômio de masson, da porção muscular. As mensurações feitas permitiram concluir que não houve diferenças signifcativas entre machos e femeas. A topografia e a presença de três aberturas (forame da veia cava caudal, hiato aórtico e esofágico) na extensão do diafragma corroboram com descrições na literatura classica para outros mamíferos. A presença de um centro tendíneo em "V" difere do encontrado para animais como o peixe-boi e porquinho-da-india, mas é similar ao encontrado para o gambá-de-orelhas-brancas e rato albino. No que diz respeito aos achados histológicos conclui-se que as fibras musculares estão dispostas de forma organizada, apresentam diâmetro grande e núcleos basais, tendo, portanto, características similares do músculo estriado esquelético tanto nos animais machos como nas fêmeas.
Resumo:
The objective of this study was to evaluate the effects of caloric restriction (CR) on myenteric neurons in the duodenum of Wistar rats during aging. Thirty rats were divided into three groups: the C group (six-month-old animals that were fed a normal diet from weaning until six months of age), the SR group (18-month-old animals that were fed a normal diet from weaning until 18 months of age) and the CR group (18-month-old animals that were fed a 30% CR diet after six months of age). After 12 months, the animals were euthanized. Whole-mount preparations of the duodenums were either stained with Giemsa or underwent NADPH-diaphorase histochemistry to determine the general myenteric neuron population and the nitrergic neuron subpopulation (NADPH-d +), respectively. The NADPH-d-negative (NADPH-d -) neuron population was estimated based on the difference between the Giemsa-stained and NADPH-d + neurons. The neurons were counted, and the cell body areas were measured. Aging was associated with neuronal loss in the SR group, which was minimized by caloric restriction in the CR group. The density (mm(2)) of the Giemsa-stained neurons was higher in the SR group (79.09 +/- 6.25) than in the CR (92.37 +/- 11.6) and C (111.68 +/- 15.26) groups. The density of the NADPH-d + neurons was higher in the SR group (44.90 +/- 5.88) than in the C (35.75 +/- 1.6) and RC (39.14 +/- 7.02) groups. The density of NADPH-d - neurons was higher in the CR (49.73 +/- 12.08) and C (75.64 +/- 17.05) groups than in the SR group (33.82 +/- 4.5). In the C group, 32% and 68% of the Giemsa-stained myenteric neurons were NADPH-d + or NADPH-d -, respectively. With aging (SR group), the percentage of nitrergic neurons (56.77%) increased, whereas the percentage of NADPH-d - neurons (43.22%) decreased. In the CR group, the change in the percentage of nitrergic (42.37%) and NADPH-d - (57.62%) neurons was lower. As NADPH-d - neurons will be mostly cholinergic neurons, CR appears to reduce the loss of cholinergic neurons during aging. The cell body dimensions (mu m(2)) were not altered by aging or CR. Thus. CR had a protective effect on myenteric neurons during aging. (C) 2012 Elsevier B.V. All rights reserved.
Resumo:
Previous studies using morphine-treated dams reported a role for the rostral lateral periaqueductal gray (rIPAG) in the behavioral switching between nursing and insect hunting, likely to depend on an enhanced seeking response to the presence of an appetitive rewarding cue (i.e., the roach). To elucidate the neural mechanisms mediating such responses, in the present study, we first observed how the rIPAG influences predatory hunting in male rats. Our behavioral observations indicated that bilateral rIPAG NMDA lesions dramatically interfere with prey hunting, leaving the animal without chasing or attacking the prey, but do not seem to affect the general levels of arousal, locomotor activity and regular feeding. Next, using Phaseolus vulgaris-leucoagglutinin (PHA-L), we have reviewed the rIPAG connection pattern, and pointed out a particularly dense projection to the hypothalamic orexinergic cell group. Double labeled PHA-L and orexin sections showed an extensive overlap between PHA-L labeled fibers and orexin cells, revealing that both the medial/perifornical and lateral hypothalamic orexinergic cell groups receive a substantial innervation from the rIPAG. We have further observed that both the medial/perifornical and lateral hypothalamic orexinergic cell groups up-regulate Fos expression during prey hunting, and that rIPAG lesions blunted this Fos increase only in the lateral hypothalamic, but not in the medial/perifornical, orexinergic group, a finding supposedly associated with the lack of motivational drive to actively pursue the prey. Overall, the present results suggest that the rIPAG should exert a critical influence on reward seeking by activating the lateral hypothalamic orexinergic cell group. (C) 2011 Elsevier B.V. All rights reserved.
Resumo:
Background: Since noradrenergic innervation was described in the ovarian follicle, the actions of the intraovarian catecholaminergic system have been the focus of a variety of studies. We aimed to determine the gonadotropin-independent effects of the catecholamine norepinephrine (NE) in the steroid hormone profile of a serum-free granulosa cell (GC) culture system in the context of follicular development and dominance. Methods: Primary bovine GCs were cultivated in a serum-free, chemically defined culture system supplemented with 0.1% polyvinyl alcohol. The culture features were assessed by hormone measurements and ultrastructural characteristics of GCs. Results: GCs produced increasing amounts of estradiol and pregnenolone for 144h and maintained ultrastructural features of healthy steroidogenic cells. Progesterone production was also detected, although it significantly increased only after 96h of culture. There was a highly significant positive correlation between estradiol and pregnenolone production in high E2-producing cultures. The effects of NE were further evaluated in a dose response study. The highest tested concentration of NE (10 (-7) M) resulted in a significant increase in progesterone production, but not in estradiol or pregnenolone production. The specificity of NE effects on progesterone productio n was further investigated by incubating GCs with propranolol (10 (-8) M), a non-selective beta-adrenergic antagonist. Conclusions: The present culture system represents a robust model to study the impact of intrafollicular factors, such as catecholamines, in ovarian steroidogenesis and follicular development. The results of noradrenergic effects in the steroidogenesis of GC have implications on physiological follicular fate and on certain pathological ovarian conditions such as cyst formation and anovulation.