RESUMO
OBJECTIVE: The aim of this study was to perform gait analysis using a pressure-sensitive walkway in dogs submitted to high (total) or low amputation (partial) of one forelimb or hindlimb. STUDY DESIGN: A total of 39 dogs met the inclusion criteria. The reasons for the amputations were motor vehicle accidents in 38 dogs and possible limb malformation in 1 dog. The amputee dogs were divided into four groups: G1 (n = 10)-high forelimb; G2 (n = 10)-low forelimb; G3 (n = 9)-high hindlimb; and G4 (n = 10)-low hindlimb. For kinetic evaluation, the dogs were walked across a pressure-sensitive walkway. RESULTS: In dogs with forelimb amputation, the percentage of body weight (%BW) distribution on the contralateral forelimb was 50.7% in cases of high amputation and 55.5% in cases of low amputation, while the %BW distribution on the hindlimbs, mainly in the ipsilateral hindlimb, was 27.9% in cases of high amputation and 27.1% in cases of low amputation. In cases of high amputation of the hindlimb, the %BW distribution was 71.5% on the forelimbs and 29.7% on the contralateral hindlimb, while in cases of low amputation, the distribution was mainly for the contralateral hindlimb and ipsilateral forelimb. No statistical difference was noted between the amputation levels, except for the contralateral limb in cases of low and high amputation of the hindlimbs concerning the overload percentage and %BW distribution. CONCLUSION: The amputation level of one forelimb did not influence the %BW distribution; however, in the hindlimb, this was higher for the contralateral limb in dogs submitted to high amputation.
Assuntos
Amputação Cirúrgica , Membro Anterior , Análise da Marcha , Membro Posterior , Animais , Cães/cirurgia , Membro Posterior/cirurgia , Análise da Marcha/veterinária , Masculino , Amputação Cirúrgica/veterinária , Feminino , Marcha , Pressão , Doenças do Cão/cirurgia , AmputadosRESUMO
Spontaneous lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve life quality for patients suffering from lymphatic disorders. This study was designed to verify if VEGFC treatment improves lymphatic vascularization in a time-dependent manner in mouse hindlimb (HL) after resection of the inguinal lymph node. Lymphatic vascular density (Vv) and length (Lv) were evaluated by stereology after immunohistochemistry. The control Group (CG) was not manipulated but received saline instead of VEGFC treatment. The surgery Group (SG) had the left inguinal lymph node resected but did not received VEGFC treatment. VEGFC Treated Group (TG) had the node resected and received VEGFC treatment. VEGFC and VEGFR3 local expression were assessed by qPCR. There was an effect of time over Vv and Lv in the SG and significant difference between CG and SG in the regions studied (proximal, medium and distal regions) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups. VEGFC and VEGFR3 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and VEGFR3 gene expression presented significant difference between CG and SG, between SG and TG and between CG and TG. This study showed significant decrease in lymphatic vascularization in the left hindlimb of mice after surgical removal of the inguinal lymph node and adjacent lymphatic vessels. Exogenous VEGFC could recover lymphatic vascularization through stimulating neolymphangiogenesis.
Assuntos
Membro Posterior/cirurgia , Excisão de Linfonodo/veterinária , Linfangiogênese , Vasos Linfáticos/cirurgia , Fator C de Crescimento do Endotélio Vascular/administração & dosagem , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
We aimed to investigate the effects of an anti-tumor necrosis factor-α antibody (ATNF) on cartilage and subchondral bone in a rat model of osteoarthritis. Twenty-four rats were randomly divided into three groups: sham-operated group (n=8); anterior cruciate ligament transection (ACLT)+normal saline (NS) group (n=8); and ACLT+ATNF group (n=8). The rats in the ACLT+ATNF group received subcutaneous injections of ATNF (20 µg/kg) for 12 weeks, while those in the ACLT+NS group received NS at the same dose for 12 weeks. All rats were euthanized at 12 weeks after surgery and specimens from the affected knees were harvested. Hematoxylin and eosin staining, Masson's trichrome staining, and Mankin score assessment were carried out to evaluate the cartilage status and cartilage matrix degradation. Matrix metalloproteinase (MMP)-13 immunohistochemistry was performed to assess the cartilage molecular metabolism. Bone histomorphometry was used to observe the subchondral trabecular microstructure. Compared with the rats in the ACLT+NS group, histological and Mankin score analyses showed that ATNF treatment reduced the severity of the cartilage lesions and led to a lower Mankin score. Immunohistochemical and histomorphometric analyses revealed that ATNF treatment reduced the ACLT-induced destruction of the subchondral trabecular microstructure, and decreased MMP-13 expression. ATNF treatment may delay degradation of the extracellular matrix via a decrease in MMP-13 expression. ATNF treatment probably protects articular cartilage by improving the structure of the subchondral bone and reducing the degradation of the cartilage matrix.
Assuntos
Adalimumab/farmacologia , Antirreumáticos/farmacologia , Osso e Ossos/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Ligamento Cruzado Anterior/cirurgia , Artrite Experimental/tratamento farmacológico , Artroplastia Subcondral , Osso e Ossos/metabolismo , Cartilagem Articular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Feminino , Membro Posterior/patologia , Membro Posterior/cirurgia , Imuno-Histoquímica , Escala de Gravidade do Ferimento , Metaloproteinase 13 da Matriz/efeitos dos fármacos , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite/cirurgia , Fatores de Proteção , Distribuição Aleatória , Ratos Sprague-DawleyRESUMO
We aimed to investigate the effects of an anti-tumor necrosis factor-α antibody (ATNF) on cartilage and subchondral bone in a rat model of osteoarthritis. Twenty-four rats were randomly divided into three groups: sham-operated group (n=8); anterior cruciate ligament transection (ACLT)+normal saline (NS) group (n=8); and ACLT+ATNF group (n=8). The rats in the ACLT+ATNF group received subcutaneous injections of ATNF (20 μg/kg) for 12 weeks, while those in the ACLT+NS group received NS at the same dose for 12 weeks. All rats were euthanized at 12 weeks after surgery and specimens from the affected knees were harvested. Hematoxylin and eosin staining, Masson's trichrome staining, and Mankin score assessment were carried out to evaluate the cartilage status and cartilage matrix degradation. Matrix metalloproteinase (MMP)-13 immunohistochemistry was performed to assess the cartilage molecular metabolism. Bone histomorphometry was used to observe the subchondral trabecular microstructure. Compared with the rats in the ACLT+NS group, histological and Mankin score analyses showed that ATNF treatment reduced the severity of the cartilage lesions and led to a lower Mankin score. Immunohistochemical and histomorphometric analyses revealed that ATNF treatment reduced the ACLT-induced destruction of the subchondral trabecular microstructure, and decreased MMP-13 expression. ATNF treatment may delay degradation of the extracellular matrix via a decrease in MMP-13 expression. ATNF treatment probably protects articular cartilage by improving the structure of the subchondral bone and reducing the degradation of the cartilage matrix.
Assuntos
Animais , Feminino , Adalimumab/farmacologia , Antirreumáticos/farmacologia , Osso e Ossos/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Osteoartrite/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Artroplastia Subcondral , Ligamento Cruzado Anterior/cirurgia , Artrite Experimental/tratamento farmacológico , Osso e Ossos/metabolismo , Cartilagem Articular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Membro Posterior/patologia , Membro Posterior/cirurgia , Imuno-Histoquímica , Escala de Gravidade do Ferimento , /efeitos dos fármacos , /metabolismo , Osteoartrite/cirurgia , Fatores de Proteção , Distribuição Aleatória , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To evaluate the postoperative analgesic effects of epidural administration of morphine and neostigmine, either alone or in combination, in dogs. ANIMALS: 30 dogs undergoing orthopedic surgery on a pelvic limb. PROCEDURES: Anesthetic protocols were standardized. At the end of surgery, 10 dogs each received 1 of 3 epidural treatments: morphine (0.1 mg/kg), neostigmine (5 µg/kg), or morphine plus neostigmine (0.1 mg/kg and 5 µg/kg, respectively). Postoperative pain scores and the need for rescue analgesia were evaluated for 24 hours. RESULTS: Pain scores were higher in the neostigmine group, compared with scores for the morphine-neostigmine group, at 2 and 24 hours after surgery and higher in the morphine group than in the morphine-neostigmine group at 2 and 4 hours. During 24 hours, rescue analgesia was provided for 4, 7, and 2 of 10 dogs each in the morphine, neostigmine, and morphine-neostigmine groups, respectively. The number of dogs given rescue analgesia was significantly different among groups at 2, 3, 4, and 6 hours after surgery. Dogs in the morphine and morphine-neostigmine groups had a lower probability of receiving rescue analgesia within 24 hours than did dogs in the neostigmine group. CONCLUSIONS AND CLINICAL RELEVANCE: When administered epidurally, morphine alone or in combination with neostigmine provided effective postoperative analgesia in most dogs after orthopedic surgery, whereas neostigmine alone did not. Findings for this study suggested a potential role for neostigmine as an adjuvant for epidural analgesia in dogs undergoing orthopedic surgeries on the pelvic limbs.
Assuntos
Analgesia Epidural/veterinária , Analgésicos Opioides/administração & dosagem , Cães/fisiologia , Morfina/administração & dosagem , Neostigmina/administração & dosagem , Dor Pós-Operatória/veterinária , Analgesia/veterinária , Analgesia Epidural/métodos , Animais , Cães/lesões , Cães/cirurgia , Quimioterapia Combinada/veterinária , Feminino , Fraturas do Fêmur/cirurgia , Fraturas do Fêmur/veterinária , Membro Posterior/lesões , Membro Posterior/cirurgia , Luxação do Quadril/cirurgia , Luxação do Quadril/veterinária , Masculino , Procedimentos Ortopédicos/veterinária , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Período Pós-Operatório , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/veterináriaRESUMO
Vascularized bone marrow transplantation (VBMT) appears to promote tolerance for vascularized composite allotransplantation (VCA). However, it is unclear whether VBMT is critical for tolerance induction and, if so, whether there is a finite amount of VCA that VBMT can support. We investigated this with a novel VCA combined flap model incorporating full-thickness hemiabdominal wall and hindlimb osteomyocutaneous (HAW/HLOMC) flaps. Effects of allograft mass (AM) and VBMT on VCA outcome were studied by comparing HAW/HLOMC VCAs with fully MHC-mismatched BN donors and Lewis recipients. Control groups did not receive treatments following transplantation. Treatment groups received a short course of cyclosporine A (CsA), antilymphocyte serum, and three doses of adipocyte-derived stem cells (POD 1, 8, and 15). The results showed that all flaps in control allogeneic groups rejected soon after VCAs. Treatment significantly prolonged allograft survival. Three of eight recipients in HLOMC treatment group had allografts survive long-term and developed donor-specific tolerance. Significantly higher peripheral chimerism was observed in HLOMC than other groups. It is concluded that the relative amount of AM to VBMT is a critical factor influencing long-term allograft survival. Accordingly, VBMT content compared with VCA mass may be an important consideration for VCA in humans.
Assuntos
Parede Abdominal/cirurgia , Transplante de Medula Óssea/métodos , Aloenxertos Compostos , Membro Posterior/cirurgia , Retalhos Cirúrgicos , Alotransplante de Tecidos Compostos Vascularizados/métodos , Animais , Medula Óssea/irrigação sanguínea , Medula Óssea/imunologia , Estudos de Viabilidade , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Tolerância Imunológica , Imunossupressores/uso terapêutico , Teste de Cultura Mista de Linfócitos , Subpopulações de Linfócitos/imunologia , Masculino , Tamanho do Órgão , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Transplante de Pele , Cauda , Quimeras de TransplanteRESUMO
Axolotls (Ambystoma mexicanum) have the ability to regenerate amputated limbs throughout their life span. In the present study, we attempted to elucidate how axolotls can specify limb type correctly during the regeneration process. We misexpressed Tbx5 in regenerating hindlimb blastema, and consequently a forelimb-like hindlimb regenerated from the hindlimb blastema. On the other hand, no change was observed in Tbx5-overexpressing forelimb blastema, and thus we considered that Tbx5 plays a key role in the specification of forelimb during the regeneration process of axolotl limbs. However, axolotls' fore- and hindlimbs have very similar structures except for the number of fingers, and it was very difficult to judge whether the forelimb-like regenerate was a true forelimb or merely a forelimb-like hindlimb. Therefore, in order to confirm our conclusion, we have to investigate other genes that are expressed differentially between fore- and hindlimbs in future experiments.
Assuntos
Ambystoma mexicanum/metabolismo , Membro Posterior/fisiologia , Regeneração/fisiologia , Proteínas com Domínio T/metabolismo , Amputação Cirúrgica , Animais , Membro Anterior/fisiologia , Membro Anterior/cirurgia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Membro Posterior/cirurgiaRESUMO
BACKGROUND: Degloving injuries may be a challenge when it comes to deciding the surgical approach to be used. Repositioning of the flap and suturing are faster and more straightforward, but often these procedures often lead to total or partial loss of the avulsed flap. Pharmacological agents with vascular properties that enhance the viability of the reattached flap could be beneficial to patients with degloving injuries. Experimental models with which to test this hypothesis are scarce. An experimental model reproducing a degloving injury of the hind limb of rats was developed in our department, and the effects of pentoxifylline (Ptx) and allopurinol (Alp) were assessed. METHODS: In all, 3 groups of rats were studied (25 rats each). A hind limb degloving model was used in all groups, resulting in a reverse flow flap. The flap was then repositioned and sutured. The control (Ct) group received only saline solution, the Ptx group received pentoxifylline (25 mg/kg), and the Alp group received allopurinol (45 mg/kg). The rats were observed for 7 days, after which they were killed, and the flap was removed. The total area of the avulsed flap and the necrotic area were measured. RESULTS: The median total flap area (cm) was 5.6 for the Ct group, 5.5 for the Ptx group, and 5.8 for the Alp group (P = 0.9465). Thus, the flaps were similar. The median necrotic flap area (cm) was 3.3 for the Ct group, 2.3 for the Ptx group, and 1.9 for the Alp group (P = 0.0001). There was a statistical difference between the Ct and Ptx groups and the Ct and Alp groups (P < 0.05). CONCLUSIONS: The areas of necrosis observed in the degloved flaps of the rats' hind limbs were smaller in the pentoxifylline and allopurinol groups. Although allopurinol seems to be more efficient, the difference was not significant.
Assuntos
Alopurinol/farmacologia , Pentoxifilina/farmacologia , Lesões dos Tecidos Moles/patologia , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Retalhos Cirúrgicos/patologia , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Membro Posterior/lesões , Membro Posterior/cirurgia , Masculino , Necrose/patologia , Necrose/prevenção & controle , Ratos , Ratos Wistar , Pele/irrigação sanguínea , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia , Lesões dos Tecidos Moles/tratamento farmacológico , Vasodilatadores/farmacologia , Xantina Oxidase/antagonistas & inibidoresRESUMO
In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.
Assuntos
Ambystoma mexicanum/fisiologia , Cartilagem Articular/fisiologia , Membro Anterior/fisiologia , Membro Posterior/fisiologia , Articulações/fisiologia , Regeneração/fisiologia , Agrecanas/genética , Agrecanas/metabolismo , Ambystoma mexicanum/anatomia & histologia , Amputação Cirúrgica , Animais , Biomarcadores/metabolismo , Cartilagem Articular/anatomia & histologia , Clonagem Molecular , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Amarelo de Eosina-(YS) , Membro Anterior/anatomia & histologia , Membro Anterior/cirurgia , Expressão Gênica , Hematoxilina , Membro Posterior/anatomia & histologia , Membro Posterior/cirurgia , Histocitoquímica , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Articulações/anatomia & histologiaRESUMO
OBJECTIVE: To report repair of a right proximal tibial Salter-Harris type II fracture in a foal with a hybrid external fixator (HEF). STUDY DESIGN: Case report. ANIMALS: A 5-month-old male foal. METHODS: After open surgical reduction, an HEF built with wires, 2 half-rings, 3 half-threaded connecting rods, and Schanz pins was used to stabilize the fracture. RESULTS: Immediately after surgery, the foal had relatively good weight bearing. The HEF was removed at 60 days after radiographic confirmation of healing. CONCLUSIONS: HEF can be used to stabilize a proximal tibial Salter-Harris type II fracture in a 5-month-old foal. CLINICAL RELEVANCE: HEF should be considered as another option for repair of proximal tibial Salter-Harris type II fractures in foals.
Assuntos
Fixadores Externos/veterinária , Fraturas Ósseas/veterinária , Doenças dos Cavalos/cirurgia , Animais , Fraturas Ósseas/cirurgia , Membro Posterior/patologia , Membro Posterior/cirurgia , Cavalos , MasculinoRESUMO
Viability and functional results of a segment replantation depend on the prevention of deleterious effects of ischemia. Prolonged ischemia leads to alterations in the microcirculation: thrombosis, edema, production of oxygen free radicals, and platelet aggregation. The effect of IIb-IIIa glycoprotein inhibitors was tested in a partial limb amputation model submitted to warm ischemia. The male Wistar rats were divided into four groups: G1 with 0 hours of ischemia and saline ( N = 20), G2 with 6 hours of ischemia and saline ( N = 24), G3 with 6 hours of ischemia and abciximab ( N = 23), and G4 with 6 hours of ischemia and tirofiban ( N = 29). The limbs were observed for 7 days and classified as viable or nonviable. Viability and mortality rates were obtained and analyzed by Q-square and Fisher exact tests ( P < 0.05). The viability rates were 100% (G1), 30% (G2), 77.78% (G3), and 80.95% (G4). G2 was statistically different from G1, G3, and G4. G1, G3, and G4 were not statistically different. Transoperative and postoperative mortalities were not statistically different. The administration of abciximab and tirofiban improved limb salvage after ischemia and reperfusion and did not modify mortality rates significantly.
Assuntos
Amputação Cirúrgica , Anticorpos Monoclonais/uso terapêutico , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Salvamento de Membro , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Tirosina/análogos & derivados , Isquemia Quente , Abciximab , Animais , Membro Posterior/cirurgia , Masculino , Microcirculação/fisiologia , Modelos Animais , Fenômeno de não Refluxo/fisiopatologia , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Wistar , Tirofibana , Tirosina/uso terapêuticoRESUMO
A 2-month-old dog was presented with injuries involving both hind paws. Only the 5th digit and its digital pad were present on the right paw. Following a full-thickness skin graft, the 5th digital pad was transferred distal to the metatarsal bones. The transferred pad permitted weight-bearing on the limb.
Assuntos
Traumatismos do Pé/veterinária , Membro Posterior/lesões , Membro Posterior/cirurgia , Transplante de Pele/veterinária , Suporte de Carga , Animais , Cães , Traumatismos do Pé/cirurgia , Masculino , Transplante de Pele/métodos , Resultado do Tratamento , Cicatrização/fisiologiaRESUMO
OBJECTIVE: To compare the pre-emptive analgesic effects of epidural ketamine or S(+)-ketamine on post-incisional hyperalgesia. STUDY DESIGN: Prospective randomized study. ANIMALS: Twenty-four mongrel dogs (1-5 years, weighing 11.9+/-1.8 kg). METHODS: Dogs were anesthetized with propofol (5 mg/kg intravenously) and a lumbosacral epidural catheter was placed. Dogs were randomly allocated to 3 groups, each with 8 dogs. The control group (CG) was administered saline solution (0.3 mL/kg); the ketamine group (KG) ketamine (0.6 mg/kg); and the S(+)-ketamine group (SG) S(+)-ketamine (0.6 mg/kg). The final volume was adjusted to 0.3 mL/kg in all groups. Five minutes after the epidural injection a surgical incision was made in the common pad of the right hind limb and was immediately closed with simple interrupted nylon suture. Respiratory (RR) and heart (HR) rates, rectal temperature (T), sedation (S), lameness score, and mechanical nociceptive threshold by von Frey filaments were evaluated before the propofol anesthesia and at 15, 30, 45, 60, 75, and 90 minutes and then at 2, 4, 6, 8, 12, and 24 hours after epidural injection. RESULTS: There were no differences in RR, HR, T, or S between groups. Motor blockade of the hind limbs was observed during 20+/-3.6 minutes in KG and during 30.6+/-7.5 minutes in SG (mean+/-SD). Mechanical force applied to obtain an aversive response was higher from 45 minutes to 12 hours in KG and from 60 to 90 minutes in SG, when compared with CG. CONCLUSIONS: Pre-emptive epidural ketamine induced no alterations in RR and HR, and reduced post-incisional hyperalgesia for a longer time than did S(+) ketamine. CLINICAL RELEVANCE: Although anesthetic and analgesic potency of S(+) ketamine is twice that of ketamine, the racemic form is seemingly better for post-incisional hyperalgesia.
Assuntos
Analgésicos/administração & dosagem , Anestesia Epidural/veterinária , Cães/fisiologia , Ketamina/administração & dosagem , Dor Pós-Operatória/veterinária , Animais , Cães/cirurgia , Membro Posterior/cirurgia , Injeções Epidurais/veterinária , Medição da Dor/veterinária , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Resultado do TratamentoRESUMO
The effects of local application of a cream containing nitric oxide (NO) donors, S-nitroso-N-acetylpenicillamine (SNAP) or isosorbide dinitrate were studied in a rat model of incision pain. An incision was made in the plantar aspect of a hind paw and the cream was applied inside the surgical wound. SNAP (1-10%) or isosorbide (2.5-5%) reduced the incision allodynia as measured with von Frey filaments. Higher concentrations produced a smaller or no effect, but SNAP (30%) intensified the allodynia. Allodynia was also intensified by SNAP (5% or 30%) in rats pretreated with intraplantar 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ, 4 microg), a guanylate cyclase inhibitor. The effect of isosorbide (5%) was prevented by ODQ. The cream containing SNAP released 10- to 20-fold more nitrite than did isosorbide from a macrophage culture. We conclude that local application of drugs generating a low NO concentration reduces incision pain through activation of guanylate cyclase. Drugs generating high NO concentrations, however, intensify pain via a guanylate cyclase-independent mechanism.
Assuntos
Doadores de Óxido Nítrico/farmacologia , Dor Pós-Operatória/prevenção & controle , Penicilamina/análogos & derivados , Animais , Modelos Animais de Doenças , Diuréticos Osmóticos/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/metabolismo , Membro Posterior/cirurgia , Hiperalgesia/prevenção & controle , Isossorbida/farmacologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitritos/metabolismo , Pomadas , Oxidiazóis/farmacologia , Limiar da Dor/efeitos dos fármacos , Dor Pós-Operatória/fisiopatologia , Penicilamina/farmacologia , Quinoxalinas/farmacologia , Ratos , Ratos Wistar , Fatores de TempoRESUMO
Justificativa e objetivos - O bloqueio do plexo braquial por via axilar, embora bastante difundido por ter menor incidência de complicações, apresenta três inconvenientes que limitam o seu uso: índice de falhas, latência longa e restrição a cirurgias de antebraço e mão. O objetivo deste estudo foi verificar o tempo de latência e a eficácia do bloqueio do plexo braquial por via axilar empregando-se um estimulador de nervo. Método - Participaram do estudo, aberto, prospectivo, 38 pacientes, estado físico ASA I, II e III, com idades entre 13 e 74 anos, submetidos a cirurgia de mebro superior. Na sala de operação, após monitorização, venóclise, sedação com 1 1 3mg de midazolam por via venosa, os pacientes foram submetidos ao bloqueio do plexo braquial por via axilar, após emprego do estimulador de nervo, com amperagens decrescentes a partir de 0,9mA e injetando-se o anestésico local, após obtenção de resposta motora dos dedos da mão, com menor amperagem. Foram observadas as latências sensitiva e motora, a eficácia e falhas sensitiva e motora, parciais ou totais, e efeitos colaterais. Resultados - As latências sensitiva e motora foram, respectivamente, 5,2ñ3,8 e 4,6ñ3,3 minutos. As falhas parciais sensitivas foram em número de seis, as motoras dez e completa duas, enquanto que em vinte casos não ocorreram falhas. Apenas em dois casos foi necessário converter para anestesia geral. Conclusões - Concluímos que, nas condições deste estudo, o uso do estimulador de nervo mostrou-se útil para a realização do bloqueio, sendo que, na maioria dos casos, não foi necessário estímulo maior que 0,3mA
Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Anestésicos Locais/administração & dosagem , Plexo Braquial , Bupivacaína/administração & dosagem , Estimulação Elétrica , Bloqueio Nervoso , Membro Posterior/cirurgiaRESUMO
Limb regeneration in the short-toes axolotl is impaired. Our goal was to characterize the regeneration process in this mutant by histological and immunocytochemical methods. Previous research indicates that age and a defective basement membrane may be instrumental factors in short-toes axolotl regeneration (Del Rio-Tsonis et al. [1992] Proc. Natl. Acad. Sci. U.S.A., 89:5502-5506). The present results show that limb regeneration can occur even in older (1-2-year-old) short-toes axolotls. The process was always significantly delayed, but the time required for complete regeneration varied. Even so, the basement membrane of short-toes regenerates showed no differences in thickness or shape compared with wild-type regenerates. Distally amputated short-toes limbs gave rise to more digits in the regenerate, indicating that regeneration may be somewhat dependent on the level of amputation. Since extracellular matrix (ECM) remodeling occurs extensively during regeneration, we compared the ECM of the short-toes and wild-type regenerates using monoclonal antibodies (mAbs) MT2 and ST1 (Tassava et al. [1996] Wound Rep. Reg., 4:75-81). The short-toes regenerates showed decreased reactivity to mAb MT2, which identifies type XII collagen, an ECM protein that is normally unregulated during regeneration, and increased reactivity to mAb ST1, which identifies a limb ECM component that typically undergoes breakdown in the distal stump. Thus, impaired regeneration in the short-toes axolotl is correlated with impaired ECM remodeling in the distal limb stump. This supports the view that ECM remodeling plays an important role in regeneration.