Análise comparativa entre a vascularização arterial ventricular e do nó sinoatrial em corações de cães / Comparative analysis between both ventricular and sinoatrial node arterial vascularization in heart of dogs

Utilizamos nesta pesquisa 40 corações de cães adultos, machos e fêmeas, de idades variadas, que não portavam nenhuma afecção cardíaca. Os corações tiveram as artérias coronárias injetadas, separadamente, com Neoprene Látex 450, corado com pigmento vermelho, e posteriormente dissecados. Em todas estas preparações verificamos que na vascularização dos ventrículos predominava a artéria coronária esquerda que fornecia os ramos interventriculares paraconal e subsinuoso. Já, a região ocupada pelo nó sinoatrial ficava mais frequentemente (17 vezes, 42,5%) na dependência do ramo proximal atrial esquerdo ou de colateral deste vaso, oriundo do ramo circunflexo esquerdo, ou deste vaso associado ao ramo distal atrial direito (8 vezes, 20%), procedente do ramo circunflexo direito. Com menor frequência (14 vezes, 30%), a área tomada pelo nó sinoatrial, encontramos apenas colaterais do ramo circunflexo direito, mais exatamente somente o ramo distal atrial direito (10 vezes, 25%), apenas o ramo proximal atrial direito (3 vezes, 7,5%) ou ainda exclusivamente o ramo intermédio atrial direito (1 vez, 2,5%). Em um único caso (1 vez, 2,5%) no território do nó sinoatrial observamos apenas colateral do ramo circunflexo esquerdo, isto é o ramo distal atrial esquerdo. A análise destes resultados permite concluir, que nesta espécie não existe qualquer tipo de relação entre o tipo de vascularização dos ventrículos e a irrigação do nó sinoatrial. Sendo assim, considerar os ramos ventriculares isoladamente não é suficiente para um entendimento clínico-cirúrgico aplicado, uma vez que os ramos atriais apresentam uma importante contribuição para a vascularização do nó sinoatrial.

We analyzed 40 hearts of adult dogs, males and females of different ages, without cardiac disease. The hearts had the coronary arteries inject using Neoprene Latex 450, colored with red pigment, and which was then dissected. In the ventricular vascularization the left coronary artery was predominant and gave rise to the paraconal interventricular and subsinuous branches. The region occupied by the sinoatrial node was most frequently (17 times, 42.5%) in dependence of the left atrial proximal branch or in the collateral branch of that vessel, coming from the left circumflex branch, or this vessel was associated with the right atrial distal branch (8 times, 20%). With less frequency (14 times, 30%), in the area occupied by the sinoatrial node we found only the collaterals of the right circumflex branch, only the right atrial distal branch (10 times, 25%), only the right atrial proximal branch (3 times, 7.5%) or exclusively the right atrial intermediary branch (once, 2.5%). In just one case (once, 2.5%) in the area of the sinoatrial node we observed only the collateral of the left circumflex branch, i.e. the left atrial distal branch. According to our results we concluded that in this specie there is no relationship between the type of ventricular vascularization and irrigation of the sinoatrial node. In doing so, to consider just the ventricular branches is not sufficient for a clinical and surgical applied understanding, since the atrial branches make an important contribution to the sinoatrial node vascularization.

The vascular system of the upper eyelid. Anatomical study and clinical interest.

Thorough knowledge of the vascular supply is indispensable for repair and oncologic surgery of the eyelids, and has a significant impact on the management of complex defects of this region. This anatomic study was performed with five fresh cadavers after arterial injection of coloured neoprene latex. The distribution of the vascular system of the upper eyelid was examined after dissection and photographic study. It is made up of three arcades: the preseptal arcade, the supratarsal arcade, and the marginal arcade, under the orbicularis oculi muscle. These arcades are supplied by branches of the ophthalmic artery (supraorbital artery, supratrochlear artery and medial palpebral artery) and branches of the facial artery and temporal artery. Small vertical branches arising out of these arcades provide an anastomotic network. This anatomical study aimed to describe the vascular system of the upper eyelid in order to search for constant features and to map the blood supply of the principal upper lid flaps.

Investigación de los efectos neurofisiológicos de la inhalación aguda de neoprén en el gato / Investigation of the neurophysiological effects of acute neopren inhalation in the cat

En 15 gatos encéfalo aislados o curarizados, se estudiaron los fectos neurofisiológicos de la inhalación aguda de disolventes orgánicos de neoprén (Tolueno, n-hexano, benceno). La actividad eléctrica se registró medinate electrodos implantados estereotáxicamente en hipocampo, amígdalas, formación reticular mesencefálica y núcleo caudado. Se hizo monitoreo de EEG y ECG. El disolvente orgánico fue impulsado por medio de la ventilación mecánica. La actividad electrográfica de base durante los 30 a 40 min que duró cada sesión experimental, varió desde los signos de máxima alerta hasta intensificación de sincronización modulada que alternó con desincronización. Frecuentemente esta actividad estuvo desfasada entre las diversas estructuras estudiadas. Se observaron descargas paroxísticas parciales principalmente en hipocampo y amígdala. También se observaron descargas paroxísticas generalizadas con orígenes aparentes distintos. En cinco gatos se hizo fotoestimulación, en dos provocó paroxismos generalizados y en uno, crisis focal amigadliana. La frecuencia óptima fue de 3 Hz

Transplante de pancreas experimental / Experimental pancreas transplantation

Experimental pancreatic transplantation was performed in dogs using different surgical techniques. Ten dogs underwent whole organ graft with diversion of exocrine secretion by anastomosis of duodenal segment to bladder (six animals) and of duodenum to a jejunal loop (four animals). Segmental pancreatic grafts were performed in 10 dogs with ductal filling with polymer in six animal and duct ligation in four dogs. It is concluded that segmental pancreatic graft with ductal filling with polymer is preferable to the other surgical techniques

Contribution of partial pancreatectomy, systemic hormone delivery, and duct obliteration to glucose regulation in canine pancreas. Importance in pancreas transplantation.

Our aim was to isolate and determine the contribution of partial pancreatectomy, systemic delivery of pancreatic hormones, and duct obliteration to glucose regulation after segmental pancreas transplantation in dogs. Fasting, postprandial, and intravenous glucose-stimulated glucose, insulin, glucagon, pancreatic polypeptide (PP), and cholecystokinin (CCK) and intravenous bombesin-stimulated PP levels were studied in beagles at three successive intervals in a crossover design. The first was 6 wk after partial (approximately 70%) pancreatectomy with intact regular enteric exocrine drainage from the duodenal pancreatic remnant, the next was 2 wk after venous transposition with systemic delivery of pancreatic hormones, and the third was 6 wk after in situ duct obliteration of the remnant. With partial pancreatectomy, K values were modestly diminished (30%), and a concomitant reduction of second-phase intravenous glucose-stimulated insulin release was observed. Other parameters were not significantly affected. Venous transposition doubled peripheral plasma levels of insulin under all conditions. Fasting glucose, PP, and CCK levels decreased slightly. Other parameters were not affected. Duct obliteration of the systemic draining pancreatic remnants seriously impaired glucose sensitivity, resulting in a 50% reduction of K values and fasting and sustained postprandial hyperglycemia (approximately 8 mM) and a 70-50% reduction (acute and overall responses, respectively) of intravenous glucose-stimulated insulin. Fasting hormone and postprandial insulin, glucagon, and CCK levels were not affected. The postprandial PP response was severely reduced, and bombesin-stimulated PP release was abolished by duct obliteration. We conclude that histological changes associated with duct obliteration are the major determinants of glucose regulation in segmental pancreas transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Pancreatic enzyme replacement therapy in post-pancreatectomy patients.

The occurrence of malnutrition and maldigestion was studied in nine patients who underwent pancreatoduodenectomy and sclerosis of the residual pancreatic stump with neoprene. The operation causes a complete loss of exocrine pancreatic function, but spares islet cell function. Upon discharge from the hospital, patients received pancreatin powder as a dietary enzyme supplement (18,000 lipase U/meal). Patients were again hospitalized 2 y after surgery for evaluation of nutritional status and digestive function (hospital checkup). Nutritional status was evaluated by measuring serum albumin, total iron binding capacity, and total lymphocytes. Digestive function was assessed by the D-xylose tolerance test and determination of fecal fat excretion. Patients were then discharged with pancrelipase enteric-coated microspheres (ECM) as a dietary enzyme supplement (16,050 lipase U/meal). Malnutrition, defined as the occurrence of at least two abnormal nutritional parameters, was observed in three patients at the time of the hospital checkup. Upon reevaluation of nutritional status after 6 mo on pancrelipase ECM, all patients were well nourished. The mean body weight, which had been 52.8 Kg immediately after surgery, increased to 54.9 Kg at the time of the hospital checkup (p less than 0.01) and to 58.0 Kg after six months of pancrelipase ECM therapy (p less than 0.05). At the hospital checkup, the D-xylose test was normal in all patients and steatorrhea had decreased from a mean of 32.8 g/d without enzyme supplementation to 16.7 g/d with pancrelipase therapy (16,050 lipase U/meal). The complete loss of exocrine pancreatic function following surgery was well tolerated. In fact, when patients were on pancrelipase therapy, much of the original body weight was recovered and the biochemical indices of malnutrition were normalized.

Correction of malnutrition and maldigestion with enzyme supplementation in patients with surgical suppression of exocrine pancreatic function.

We studied the occurrence and extent of malnutrition and maldigestion in 13 patients who underwent pancreatoduodenectomy (PD) and injection of Neoprene (polychloroprene) (NI) into the duct of Wirsung, which results in sclerosis of hte acinar pancreatic tissue, but spares the endocrine function. At discharge, patients under took an enzyme supplementation regimen with pancreatin (18, 00 United States Pharmacopoeia units of lipase per meal). Patients were rehospitalized 24.9 months after PD plus NI to undergo nutritional and metabolic evaluation (hospital control). Nutritional status was evaluated by measuring the serum albumin level, total iron binding capacity and total lymphocyte count. Digestive function was assessed by the D-xylose tolerance test and determination of fecal fat excretion. Patients were then discharged with pancrelipase, enteric-coated microspheres (ECM) supplementation (16,050 United States Pharmacopoeia units of lipase per meal). Malnutrition, defined as the occurrence of at least two abnormal nutritional parameters, was observed in six patients at hospital control. After six months on pancrelipase ECM, the nutritional status was re-evaluated in nine patients (three previously malnourished) who were all well nourished. The mean body weight was 84.7 per cent of usual body weight at discharge after PD plus NI and raised to 88.0 per cent at the hospital control (p less than 0.01) and to 93.7 per cent )p less than 0.05) after six months on pancrelipase ECM. At hospital control, results from the D-xylose test were normal in all patients, and steatorrhea dropped from 33.6 grams per day without enzyme supplementation to 15.3 grams per day with pancrelipase ECM (16,050 United States Pharmacopoeia units of lipase per meal). Steatorrhea was incompletely but satisfactorily corrected by pancrelipase ECM. On supplementation therapy with pancrelipase ECM, patients recover a good deal of the body weight and normalize the biochemical indices of malnutrition.

Pancreatic duct obliteration: clinical application, morphological and functional effects.

Pancreatic duct obliteration is a procedure to abolish exocrine secretion in order to prevent complications such as leakage, abscess and fistula occurring formation after diversion techniques like pancreatico-enterostomy. Pancreatic duct obliteration is applicable after all sorts of partial pancreatic resections, pancreas transplantation included. Although the method is safe, experiments have shown that not only complete exocrine atrophy is induced, but that also the endocrine architecture is destroyed. In dogs, the destruction of islet architecture leads to about 70% reduction of the insulin secreting capacity. It is not known whether such a severe reduction of endocrine function also occurs after pancreatic duct obliteration in man. This would discard duct obliteration as a procedure suitable for pancreas transplantation, since optimal endocrine pancreas function is the aim of pancreas transplantation in patients suffering from type-I diabetes mellitus.

Progress in segmental neoprene-injected pancreas transplantation. Advantages and disadvantages of using Cyclosporin A.

We performed 39 neoprene-injected pancreatic transplants (38 segmental and 1 total) in 37 insulin-dependent diabetic recipients from October 1976 to May 1983. The best results were obtained when the pancreas was transplanted simultaneously with the kidney (25 cases). The use of Cyclosporin A (CyA) for immunosuppression did not reduce the early pancreatic failures, but it seems to have slightly improved the long-term survival. The glycaemic control was better in patients treated by CyA alone than in those receiving steroids. The main side effects of CyA were nephrotoxicity and some immunoglobulin abnormalities with or without lymphoproliferative disorders occurring after treatment with CyA and ALG.