Navegando por Palavras-chave "sciatic nerve"

Agora exibindo 1 - 5 de 5
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Abnormal extrapelvic course of the inferior gluteal artery
    (Springer, 1997-06-01) Gabrielli, C.; Olave, E.; Sarmento, A.; Mizusaki, C.; Prates, J. C.; UNIV LA FRONTERA; Universidade Federal de São Paulo (UNIFESP)
    At its extrapelvic course the inferior gluteal a. is found to be strictly related to the sciatic n. This relationship has been described in a general way, emphasizing its medial localization in respect to the nerve. Clinicosurgical reports describe cases of aneurysms of the inferior gluteal a. on its extrapelvic course and subsequent compression at the nerve. in order to get further details on the relationship between these two structures, 80 gluteal regions from 40 cadavers of adult Brazilian individuals, 29 males and 11 females, were dissected. the inferior gluteal a. was found medial to the sciatic n. in 62 cases (77.5%); in the 18 remaining (22.5%) the trunk of the artery or one of its branches perforated the nerve. of these, 14 (77.8%) were males and 4 (22.2%) females. This disposition was found 8 times (44.4%) on the right and 10 (55.6%) on the left side; was unilateral in 4 individuals (1 on the right and 3 on the left side) and bilateral in 7. the course of the inferior gluteal a. through the sciatic n. and/or the presence of aneurysms of this artery should be considered as a possible cause of nerve compression.
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Bone marrow cells are able to increase vessels number during repair of sciatic nerve lesion
    (Elsevier B.V., 2008-05-15) Fernandes, Marcela [UNIFESP]; Valente, Sandra Gomes [UNIFESP]; Silva Fernandes, Maria Jose da [UNIFESP]; Villar Felix, Evandro Penteado [UNIFESP]; Naffah Mazzacoratti, Maria da Graca [UNIFESP]; Scerni, Debora Amado [UNIFESP]; Gomes dos Santos, Joao Baptista [UNIFESP]; Leite, Vilnei Mattioli [UNIFESP]; Faloppa, Flavio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The aim of this study was to compare the outcomes of nerve autografts (GRF) and venous grafts containing mononuclear bone marrow cells (BMCs) in sciatic nerve-lesioned rats. Control animals underwent sham operations (SHAM), received empty venous grafts (EPV), or received venous grafts containing BMC vehicle (AGR). Outcome was evaluated through sciatic functional index (SIFI), morphometric and morphologic analyses of the nerve distal to the lesion, and the number of spinal cord motor neurons positive for the retrograde tracer, Fluoro-Gold (R). All groups exhibited poor results in SFI when compared to SHAM animals throughout the postoperative period. All groups also had a significantly greater fiber density, decreased fiber diameter, and decreased motor neuron number than the SHAM group. No significant difference between the GRF and BMC groups was observed in any of these parameters. On the other hand, vessel density was significantly higher in BMC than all other groups. BMC-containing venous grafts are superior to nerve autografts in increasing vessel density during sciatic nerve regeneration. (c) 2007 Elsevier B.V. All rights reserved.
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    Bone marrow-derived mesenchymal stem cells versus adipose-derived mesenchymal stem cells for peripheral nerve regeneration
    (Medknow Publications & Media Pvt Ltd, 2018) Fernandes, Marcela [UNIFESP]; Valente, Sandra Gomes [UNIFESP]; Sabongi, Rodrigo Guerra [UNIFESP]; Gomes dos Santos, Joao Baptista [UNIFESP]; Leite, Vilnei Mattioli [UNIFESP]; Ulrich, Henning; Nery, Arthur Andrade; da Silva Fernandes, Maria Jose [UNIFESP]
    Studies have confirmed that bone marrow-derived mesenchymal stem cells (MSCs) can be used for treatment of several nervous system diseases. However, isolation of bone marrow-derived MSCs (BMSCs) is an invasive and painful process and the yield is very low. Therefore, there is a need to search for other alterative stem cell sources. Adipose-derived MSCs (ADSCs) have phenotypic and gene expression profiles similar to those of BMSCs. The production of ADSCs is greater than that of BMSCs, and ADSCs proliferate faster than BMSCs. To compare the effects of venous grafts containing BMSCs or ADSCs on sciatic nerve injury, in this study, rats were randomly divided into four groups: sham (only sciatic nerve exposed), Matrigel (MG
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    The effects of adrenalectomy in blood flow adjustments produced by sciatic nerve stimulation in rats
    (Elsevier B.V., 2004-05-31) Possas, O. S.; Lopes, O. U.; Universidade Federal de São Paulo (UNIFESP)
    Sciatic nerve stimulation (SNS) produces hypertension, tachycardia, vasodilatation in the stimulated limb and vasoconstriction in the limb contralateral to the stimulation site. These autonomic adjustments represent an equivalent of the cardiovascular responses described as features of defense-alerting reactions. However, while the muscle vasodilatation observed in rats during stimulation of hypothalamic sites involved in defense reactions has been referred to as a general, non-selective increase in blood flow, previous studies conducted on cats have demonstrated that high-intensity cutaneus stimulation produces vasodilatation in the stimulated limb and vasoconstriction in the other limbs. in anesthetized rats, the effects of SNS in the muscle vascular territory of the contralateral limb, as well as the participation of circulating catecholamines in these adjustments continued to be unknown. Therefore, in the present study we investigated the blood flow adjustments elicited by SNS in the stimulated and in the contralateral hind limbs before and after bilateral adrenalectomy. in urethane-anesthetized, paralyzed, and artificially ventilated rats, SNS (800-1000 muA, 1 ms, 100 Hz, 10 s) produced hypertension, tachycardia, vasodilatation in the stimulated hindlimb and vasoconstriction in the contralateral hindlimb. After bilateral adrenalectomy the pressor responses to SNS were abolished, the vasodilatation in the stimulated limb was greater and the vasoconstriction in the contralateral limb was replaced by vasodilatation. These results suggest that the vasodilatation in the stimulated limb does not depend on circulating catecholamines. (C) 2004 Elsevier B.V. All right reserved.
  • Nenhuma Miniatura disponível
    Item
    Somente Metadadados
    Glutamatergic and GABAergic inputs to the RVL mediate cardiovascular adjustments to noxious stimulation
    (Amer Physiological Soc, 2001-02-01) Possas, Olga Sueli [UNIFESP]; Lopes, Oswaldo Ubriaco [UNIFESP]; Cravo, Sergio Luiz [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Stimulation of cutaneous and muscle afferents induces several cardiovascular adjustments such as hypertension, tachycardia, and muscle vasodilation. Although previous studies have demonstrated that the rostral ventrolateral medulla (RVL) mediates sympathoexcitation and pressor responses to sciatic nerve stimulation (SNS), whether it also mediates blood flow adjustments remains unclear. Therefore, in the present study, we examined the role of the RVL in the vasodilation induced by SNS and the possible neurotransmitters involved. In Urethane-anesthetized, paralyzed, and artificially ventilated rats, SNS (square pulses, 1 ms, 20 Hz, 800-1200 muA, 10 s) produced increases in blood pressure, heart rate, blood flow, and vascular conductance of the stimulated limb. Unilateral microinjection of kainic acid (2 nmol/100 nl) into the RVL contralateral to the stimulated limb abolished cardiovascular adjustments to SNS. Unilateral microinjections of kynurenic acid (2 nmol/100 nl) selectively abolished the pressor response to SNS, whereas bicuculline (400 pmol/100 nl) abolished the increases in blood flow without changing the pressor response. These results suggest that glutamatergic synapses within the RVL mediate pressor responses, whereas GABAergic synapses may mediate the vasodilation to SNS.