Iliac osteosynthesis with nylon clamp associated to polymethylmethacrylate bone cement - experimental study in dogs cadavers

Fractures of iliac body are generally consequences of traumas of great impact. These fractures lead to a lack of locomotor response and in specific cases, surgery is needed. Among the possible therapeutic lines, implants become a good option. In this paper, the authors used dog corpses to develop a surgery technique of iliac osteosynthesis, employing nylon clamps and bone cement of polymethylmethacrylate (PMMA). Sixteen hemi pelvises of eight dog corpses, which had its iliac bodies totally fractured previously, were utilized. The osteosynthesis was reached through the implantation of six nylon clamps, distributed equally between the bone fragments. With the use of the nylon clamps there were bone realignment and a contact surface to fixation of the biomaterial. The technique developed in corpses was easily executed, effective in reduction, alignment and stabilization of the fracture. The authors suggest more studies in vitro to evaluate immobilization resistance and functionality in dogs with this condition.

Métodos para estudo das respostas metabólicas de cães e gatos a diferentes alimentos

Durante o processo de assimilação e uso dos alimentos, diferentes respostas metabólicas podem ser desenvolvidas pelo organismo dos animais. Estas respostas são fruto da integração de mecanismos complexos, que envolvem os sistemas neuro-endócrino e o funcionamento dos órgãos, sendo influenciadas pela dieta, espécie animal, idade, condição fisiológica e composição corporal. Este trabalho enfoca a importância fisiológica e os métodos de estudo das respostas pós-prandiais aos carboidratos, bem como as alterações fisiológicas conseqüentes ao balanço eletrolítico da dieta. A quantidade, estrutura química e processamento industrial do amido determinam boa parte da resposta pós-prandial de glicose e insulina de cães. em gatos, outros mecanismos parecem ser mais importantes, como a ingestão de aminoácidos. A fibra alimentar também altera a resposta pós-prandial ao alimento, devendo ser consideradas sua quantidade, solubilidade e fermentabilidade no desenvolvimento das dietas. Os métodos de estudo destas respostas incluem avaliação das respostas glicêmica e insulínca pós-prandiais, teste endovenoso de tolerância à glicose e à arginina. O clâmp euglicêmico apresenta-se também como ferramenta de estudo, no entanto revela informações mais relacionadas ao animal do que à dieta. A compreensão do conjunto de alterações metabólicas aos carboidratos é importante no estudo do controle da saciedade, composição corporal e inúmeras doenças degenerativas e endócrinas. A concentração e relação entre os macro-elementos da dieta (Na, Cl, K, P, Ca, Mg e S) e dos aminoácidos sulfurados (metionina, cistina e taurina) interferem em inúmeras funções orgânicas, como a cardiovascular, neuromuscular, metabolismo ósseo, renal e pulmonar, refletindo-se no equilíbrio hidro-eletrolítico e ácido-básico orgânicos. de importância prática para cães e gatos encontram-se a relação destes nutrientes com cardiopatias, nefropatias, osteodistrofias e urolitíases. A relação entre os macro-elementos é estabelecida em mmol/kg de matéria seca da dieta, calculando-se seu balanço cátion-ânion (excesso de bases ou ânions dietéticos não determinados). Suas repostas orgânicas são medidas, dentre outros métodos, pela hemogasimetria, balanço hídrico, mensuração do volume dos espaços extracelular e vascular, supersaturação e pH urinários.

Determination of the sevoflurane sparing effect of methadone in cats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clampe de Ganz no tratamento de urgência em lesões do anel pélvico

OBJETIVO: Avaliar a eficiência do clampe de Ganz na estabilização e redução dos deslocamentos da pelve, quando utilizado no tratamento de urgência, além de aquilatar eventuais dificuldades e facilidades do método. MÉTODOS: O clampe de Ganz foi utilizado no tratamento de urgência em 31 pacientes com graves lesões do anel pélvico (Tile C) associadas a importante instabilidade hemodinâmica. RESULTADO: Entre os pacientes, 27 (87,1%) apresentaram evolução favorável, com estabilização, redução dos deslocamentos e compressão da região posterior do anel, além de estabilização hemodinâmica, e quatro (12,9%) evoluíram para óbito. CONCLUSÃO: O clampe de Ganz mostrou-se eficiente ferramenta no tratamento de urgência das lesões do anel pélvico, por ser de concepção simples, de rápida colocação, não impedir ou dificultar procedimentos no abdome e, principalmente, por permitir a estabilização da pelve, redução dos deslocamentos e compressão na região posterior do anel, local onde ocorrem os maiores sangramentos, reduzindo-os ou eliminando-os.

Trimetazidine and N-acetylcysteine in attenuating hind-limb ischemia and reperfusion injuries: experimental study in rats

Aim. Lower-limb traumatic injury associated with ischemia and followed by reperfusion (I/R) is a common severe situation in muscle lesions due to trauma and hypoxia followed by local and systemic injuries induced by oxygen-derived free radical release during reperfusion. The aim of this study was to evaluate the attenuating effects of trimetazidine (TMZ) and N-acetylcysteine (NAC) in such situation.Methods. The muscles at the root of the right hind limb of Wistar rats were cross-sectioned, preserving femoral vessels and nerves and clamping the femoral artery for four hours. The clamp was then released and the femoral artery has been reperfused for 2 hours. Rats were randomly divided in groups of ten as follows: Group 1: sham I/R, treated with saline; Group 2: I/R, treated with saline; Group 3: sham I/R, treated with TMZ (7.5 mg/kg/dose); Group 4: sham I/R, treated with NAC (375 mg/kg/dose); Group 5: I/R treated with TMZ (7.5 mg/kg/dose); Group 6: I/R treated with NAC (375 mg/kg/dose). All rats received two intravenous bolus injections of the drugs, one before ischemia and one before reperfusion. Oxidative stress in plasma (MDA, total, oxidized and reduced glutathione), creatinephosphokinase (CPK), optical and electron microscopy and pelvic extremity circumference and volume were studied.Results. No statistical differences were found between the groups for MDA or total and reduced glutathione. Oxidized glutathione increased significantly in groups 5 and 2. Limb circumference as well as limb volume increased in all groups over time, mainly in groups 5, 2 and 1. CPK increased in all groups, being highest in groups 5, 6 and 2. Histological lesions were present in all but sham groups, being less severe in group 6. Soleus muscle analyses at electron microscopy exhibit some degree of alteration in all groups.Conclusion. This experimental model simulated severe limb trauma associated with ischemia and reperfusion, and, as such, it was aggressive, causing severe injury and local inflammatory reaction. The model did not show antioxidant action from NAC, and possible antioxidant action from TMZ was insufficient to attenuate tissue injuries. [Int Angiol 2009;28:412-7]

Insulin secretion, insulin sensitivity, and hepatic insulin extraction in first-degree relatives of type 2 diabetic patients

To identify early metabolic abnormalities in type 2 diabetes mellitus, we measured insulin secretion, sensitivity to insulin, and hepatic insulin extraction in 48 healthy normal glucose-tolerant Brazilians, first-degree relatives of type 2 diabetic patients (FH+). Each individual was matched for sex, age, weight, and body fat distribution with a person without history of type 2 diabetes (FH-). Both groups were submitted to a hyperglycemic clamp procedure (180 mg/dl). Insulin release was evaluated in its two phases. The first was calculated as the sum of plasma insulin at 2.5, 5.0, 7.5, and 10.0 min after the beginning of glucose infusion, and the second as the mean plasma insulin level in the third hour of the clamp procedure. Insulin sensitivity index (ISI) was the mean glucose infusion rate in the third hour of the clamp experiment divided by the mean plasma insulin concentration during the same period of time. Hepatic insulin extraction was determined under fasting conditions and in the third hour of the clamp procedure as the ratio between C-peptide and plasma insulin levels. FH+ individuals did not differ from FH- individuals in terms of the following parameters [median (range)]: a) first-phase insulin secretion, 174 (116-221) vs 207 (108-277) µU/ml, b) second-phase insulin secretion, 64 (41-86) vs 53 (37-83) µU/ml, and c) ISI, 14.8 (9.0-20.8) vs 16.8 (9.0-27.0) mg kg-1 min-1/µU ml-1. Hepatic insulin extraction in FH+ subjects was similar to that of FH- ones at basal conditions (median, 0.27 vs 0.27 ng/µU) and during glucose infusion (0.15 vs 0.15 ng/µU). Normal glucose-tolerant Brazilian FH+ individuals well-matched with FH- ones did not show defects of insulin secretion, insulin sensitivity, or hepatic insulin extraction as tested by hyperglycemic clamp procedures.

Fertilizing Capacity of Frozen Epididymal Sperm Collected from Dogs

The collection of epididymal sperm may be a valuable tool for canine reproduction especially since it can enable collection of cells after death of a valuable dog. The aim of the present study was to evaluate the viability of epididymal sperm after freeze-thawing. Epididymides were obtained from four adult dogs by elective orchiectomy. The caudal portion of the epididymides and part of the deferential ducts were squeezed by means of an anatomic clamp into a Petri dish containing either 0.9% saline solution (Group 1) or Ringer solution without lactate (Group 2). Samples were centrifuged at 800 x g for 10 min, the supernatant was removed and the pellet was diluted in one step with a Tris/citric acid/OEP (Orvus Es Paste) extender containing 7% glycerol and subjected to semen freezing. Oocytes were obtained from canine ovaries, after ovariohysterectomy. Only oocytes that were approximately 100 mu m in diameter, with a dark ooplasm surrounded by three-or four-well formed cumulus cell layers were used for sperm testing. Frozen semen samples were thawed in a water bath at 70 degrees C for 8 s and analysed at room temperature for sperm motility and velocity. Oocytes were incubated with spermatozoa in humidified atmosphere containing 5% CO(2) at 38 degrees C for 18 h. Morphological and functional characteristics of spermatozoa were similar in both groups. However, the percentage of sperm cells bound to oocytes was significantly higher in Group 2 than in Group 1. This result suggests that the Ringer solution without lactate was a more suitable medium for collecting epididymal canine sperm than 0.9% saline.

Effect of lidocaine on the minimum alveolar concentration of sevoflurane in dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Demographic and metabolic characteristics of individuals with progressive glucose tolerance

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeitos da injeção de solução bicarbonatada de ácido acetilsalicílico em mucosa colorretal de coelhos, com vistas a aplicação no preparo pré-operatório do cólon

INTRODUÇÃO: A recidiva local no câncer colorretal tem como principal causa o implante de células tumorais nas anastomoses. 11-15 Dessa maneira, lavagem química do lúmen intestinal é preconizada para evitar tanto o implante quanto à recidiva local. 11-28 em estudos prévios constatamos que a solução bicarbonatada de ácido acetilsalicílico tem efeitos citolíticos e anti-tumorais in-vitro.31 OBJETIVOS: Avaliar a toxicidade da solução de aspirina na mucosa colônica de coelhos com o objetivo de usá-la no preparo intestinal de portadores de câncer colorretal. MATERIAIS E MÉTODOS: Foram utilizados 20 coelhos. Um clampe vascular foi colocado acima do cólon sigmóide. Os animais foram submetidos a um enema com 50 ml da solução de aspirina ou soro fisiológico de acordo com o grupo. Os animais foram sacrificados ao término do procedimento ou tardiamente de acordo com o grupo. RESULTADOS: A solução de aspirina não altera a mucosa colônica de coelhos. CONCLUSÃO: O uso da solução bicarbonatada de ácido acetilsalicílico no preparo intestinal de portadores de câncer colorretal é clinicamente possível.

Differential effects of novel wasp toxin on rat hippocampal interneurons

We studied the effects of a wasp toxin beta-pompilidotoxin (beta-PMTX) on rat hippocampal CA1 interneurons by the current-clamp technique. The firing patterns of pyramidal neurons and pyramidale interneurons were not affected by beta-PMTX, but in oriens and radiatum interneurons, beta-PMTX converted the action potentials to prolonged depolarizing potentials by slowing the inactivation of Na+ channels. In lacunosum moleculare interneurons, beta-PMTX induced initial bursting spikes followed by block of succeeding spikes. Comparison of beta-PMTX with a sea anemone toxin, ATX 11, revealed that ATX 11 altered the firing properties of pyramidal neurons and pyramidale interneurons that were unchanged by beta-PMTX. Our results suggest that beta-PMTX modulates Na+ currents in CAl interneurons differently in various CAl neurons and the toxin is useful to classify Na+ channel subtypes. (C) 2002 Elsevier B.V. Ireland Ltd. All rights reserved.

Brazilian individuals with impaired glucose tolerance are characterized by impaired insulin secretion

Background: To better understand the pathogenesis of type 2 diabetes mellitus, insulin secretion and insulin sensitivity (IS) were evaluated in white Brazilians with impaired glucose tolerance (IGT), using the oral glucose tolerance test (OGTT) and the hyperglycemic clamp technique.Methods: Twenty-five IGT subjects were individually matched with normal glucose-tolerant (NGT) subjects for demographic characteristics, At first, they were submitted to the OGTT and plasma glucose and insulin were measured. of the 25 pairs, 20 could participate in the hyperglycemic clamp procedures, at a second visit. All participants had their plasma glucose levels equally increased to 180 mg/dl; this was maintained for three hours by variable glucose infusion. During the procedure, plasma glucose and insulin were measured at established intervals.Results: In the postabsorptive state, the IGT subjects presented higher levels of plasma glucose, blood HbA(1) and serum triglycerides, but similar plasma insulin levels. After the oral glucose load, early and total insulin release, in relation to glucose levels, were respectively, 43 and 67% lower in the IGT individuals, the index of whole-body IS was increased in the IGT individuals (4.36 +/- 1.71 vs 3.61 +/- 1.28 mg(-1).muU(-1) 100.ml(2); p < 0.05). By the hyperglycemic clamp technique first- (82 &PLUSMN; 26 vs 215 &PLUSMN; 88 μU/ml; p < 0.001) and second- (36 +/- 19 vs 73 +/- 44 muU/ml; p < 0.05) phases of insulin secretion was decreased in the IGT individuals, especially the first one. However, the groups did not differ in relation to the IS: IGT = 13.52 &PLUSMN; 7.27 and NGT = 9.96 &PLUSMN; 6.70 mg.ml/kg.μU.min(-1); p > 0.05. Functional relationship of IS (y) on first-phase insulin release (x) showed a smaller (p < 0,05) regression coefficient for the IGT group.Conclusion: Brazilians with IGT well-matched with NGT ones were characterized by impaired first- and second-phase insulin secretion (mainly the former), while defects in IS were not evident.

Investigations on the new free radical scavenger polynitroxyl-albumin to prevent ischemia and reperfusion injury after orthotopic heart transplantation in the pig model

Objective: Nitroxides have strong antioxidant capacity but their effectiveness is limited by their rapid intracellular inactivation. Poly nitroxyl-Albumin (PNA) is capable of regenerating inactivated nitroxide. We tested the effect of PNA against reperfusion injury in heart transplantation. Methods: Pig hearts were transplanted orthotopically. In the control group (n = 9) reperfusion was performed without reperfusion modifications. In the experimental group (n = 10) 1 ml/kg PNA was given before cross-clamp release. Results: Hemodynamic performance was impaired after transplantation in both groups without significant intergroup differences. Plasma malonedialdehyde levels were significantly diminished in the PNA group as compared to the controls. CK-MB levels in both groups were increased within the first 2 h of reperfusion without significant intergroup differences. In contrast, there were found significant higher values of myocardial specific lactate dehydrogenase (LD1) in the controls versus PNA group. Conclusions: PNA was able to reduce lipid peroxidation and attenuate free radical activity. Contractile dysfunction could no be improved, indicating that (a) the radical scavenging effect was to weak or (b) other mechanisms than free oxygen radicals are responsible for myocardial damage in this experimental model. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Modulation of intercellular communication in macrophages: possible interactions between GAP junctions and P2 receptors

Gap junctions are connexin-formed channels that play an important role in intercellular communication in most cell types. In the immune system, specifically in macrophages, the expression of connexins and the establishment of functional gap junctions are still controversial issues. Macrophages express P2X(7) receptors that, once activated by the binding of extracellular ATP, lead to the opening of transmembrane pores permeable to molecules of up to 900 Da. There is evidence suggesting an interplay between gap junctions and P2 receptors in different cell systems. Thus, we used ATP-sensitive and -insensitive J774.G8 macrophage cell lines to investigate this interplay. To study junctional communication in J774-macrophage-like cells, we assessed cell-to-cell communication by microinjecting Lucifer Yellow. Confluent cultures of ATP-sensitive J774 cells (ATP-s cells) are coupled, whereas ATP-insensitive J774 cells (ATP-i cells), derived by overexposing J774 cells to extracellular ATP until they do not display the phenomenon of ATP-induced permeabilization, are essentially uncoupled. Western-blot and reverse-transcription polymerase chain reaction assays revealed that ATP-s and ATP-i cells express connexin43 (Cx43), whereas only ATP-s cells express the P2X(7) receptor. Accordingly, ATP-i cells did not display any detectable ATP-induced current under whole-cell patch-clamp recordings. Using immunofluorescence microscopy, Cx43 reactivity was found at the cell surface and in regions of cell-cell contact of ATP-s cells, whereas, in ATP-i cells, Cx43 immunoreactivity was only present in cytosolic compartments. Using confocal microscopy, it is shown here that, in ATP-s cells as well as in peritoneal macrophages, Cx43 and P2X(7) receptors are co-localized to the membrane of ATP-s cells and peritoneal macrophages.

Subclinical abnormalities of glucose metabolism in Brazilian women with a history of gestational diabetes mellitus

Background. To evaluate insulin release and insulin sensitivity in women with prior gestational diabetes mellitus (GDM) to gain a better understanding of type 2 diabetes pathogenesis.Methods. GDM women were individually matched for age, body mass index, and waist/hip ratio with those who were normal glucose tolerant in a previous pregnancy (NGT). All women presented with normal glucose tolerance. Twenty pairs were submitted to the oral glucose tolerance test (OGTT) with plasma glucose, insulin, and C-peptide determinations. of the 20 pairs, 18 participated in hyperglycemic (10.0 mmol/l) clamp experiments with frequent plasma glucose and insulin determinations, allowing us to calculate first- and second-phase insulin release and the insulin sensitivity index. GDM and NGT women were compared using Student's t-test, the Mann-Whitney U-test, Friedman's non-parametric test, and the two proportion test for independent groups.Results. GDM women showed higher glycosylated hemoglobin values; at OGTT, they showed late insulin peak with increased plasma insulin levels only during the second hour, and a similar plasma C-peptide response despite a higher plasma glucose curve; during hyperglycemic clamp procedures, they showed similar biphasic insulin release and insulin sensitivity index. Considering that a woman with previous GDM had a defect in insulin release and/or insulin sensitivity, if its magnitude was at least 25% lower than that of the matched NGT woman, 43.8% showed impairment of first-phase insulin release and 55.6% insulin resistance.Conclusions. GDM women showed some degree of glucose intolerance. It is therefore necessary to follow them for a longer time.