Paulo de Oliveira Gomes

Evaluation of the longitudinal musculature of segments of the distal colon interposed following extended jejunum-ileum resection.

Several morbid conditions may necessitate extensive intestinal resection, leading to short‐bowel syndrome. When clinical treatment becomes inefficient, a surgical approach is necessary. Distal colon interposition is one of the viable techniques. The interposition of colon segments between remnants of the small bowel improved lifestyle, increased transit time, and diminished diarrhea. The aim of this study is to observe the longitudinal muscular contractions after distal colon interposition. Sixteen male Wistar rats (EPM‐1) were submitted to an 80% small bowel resection associated with a partial colectomy of the distal colon immediately after the bifurcation of the middle colic artery followed by a 3‐cm isoperistaltic distal colon interposition. After 70 days, the animals were submitted to euthanasia and segments of the jejunum, ileum, remnant colon, and interposed colon were prepared for pharmacological tests. The isometric contractions were measured by a poligraph. After 30 minutes, the dose/effect curves were obtained for both metacholine and barium chloride stimulation through the extraluminal surface (serosa). After this period, we observed a significant increase in the length, diameter, and thickness of the intestinal wall. Regarding the sensibility (pD2), no difference was found (interposed colon = 7.21 ± 0.2; remnant colon = 7.65 ± 0.1; remnant jejunum 7.46 ± 0.1; and remnant ileum 7.57 ± 0.1), even though the animals were submitted to different procedures. In relation to the maximal effect (Emax), the longitudinal muscle contraction responses (interposed colon = 11.79 ± 0.1; remnant jejunum = 15.42 ± 0.2; and remnant ileum = 11.48 ± 0.2) were lower than those of the remnant colon (Emax = 22.42 ± 0.1). This means that there was a possible adaptation of colonic segments to their new location.

Oxigenoterapia hiperbárica em lesões actínicas de colo de ratos: aspectos morfológicos e morfométricos

Objetivo: Avaliar a acao da oxigenacao hiperbarica em lesoes actinicas provocadas por radiacao ionizante no colo distal de ratas. Metodos: Foram utilizadas 32 ratas adultas distribuidas em quatro grupos. I - sham; II - oxigenoterapia hiperbarica (OHT); III - radioterapia (RT), e IV - radioterapia e oxigenoterapia hiperbarica (da mesma maneira que nos grupos II e III). Segmentos de colo distal foram fixados em formol a 10% e processados para avaliacao histologica e morfometrica. Resultados: Os resultados do experimento mostraram lesao das glândulas intestinais, vasodilatacao e infiltrado leucocitario na lâmina propria e submucosa no colo dos animais pertencentes ao grupo RT que diminuiu acentudadamente apos a oxigenioterapia hiperbarica. Conclusao: A oxigenitoterapia hiperbarica atenua as alteracoes morfologicas da mucosa e submucosa do colon distal de ratas com enterite induzida por radiacao ionizante.

Aspectos ultra-estruturais das vilosidades intestinais após o clampeamento do pedículo hepático de ratos

PURPOSE: To study the ultrastructural of rat intestinal villi (ileum) after total hepatic pedicle clumping for different period of time. METHODS: Forty male rats were divided into four groups of ten animals each. The Sham group was not being submitted to ischemia (control). E1, E2 and E3 group were submitted to 10, 20 and 30 minutes of ischemia, respectively. At the end of the experiment fragments of the ileum were taken off and examined by electromicroscope. RESULTS: Leucocyte infiltration, vascular dilation and electrotransparent areas were observed in intestinal villi of lamina propria of E1 and E2 groups. In reference to group E3 desquamation of epithelial layer, desquamation of intestinal villi and signs of apoptosis were observed. Hemorrhagic areas, dilated lymphatics and blood vessels and lots of leucocytes were observed in lamina propria. CONCLUSION: The clumping of hepatic pedicle provokes esplacnic congestion, time dependent, and to the 30 minutes were epithelial cell desquamation, apoptosis signs and hemorrhage.

Estudo funcional e morfológico da hipotermia sistêmica ou tópica no fígado de cães

PURPOSE To compare hepatic lesions produced by two types of hypothermia; the systemic and the local or topic. METHODS Twenty dogs distributed in two groups were studied: the first submitted to local hypothermia and the second to systemic hypothermia. In all groups, biochemical dosages for alanina allytransferase (A.L.T.), aspartate aminotrasnferase (A.S.T.) and direct bilirubin (T.D.), conventional optical microscopy and electronic transmission microscopy were performed in times T0, Test, and T60, that is, before the hypothermia (T0), after temperature stabilization at 10 degrees lower than initial temperature (Test), and after sixty minutes of hypothermia (T60). RESULTS The data analysis, both of the biochemical profile and of the microscopy showed that in the group of animals with selective hypothermia, the hepatic lesions were more intense when compared to the systemic hypothermia group. CONCLUSION The selective hypothermia causes more lesions to the liver than the systemic.

Model of extensive and severe tracheal stenosis in dogs

PURPOSE To create an animal model of extensive longitudinal tracheal stenosis (TS) that can be useful to test different surgical techniques of tracheal reconstruction. METHODS Twenty male mongrel dogs were submitted to standard TS and randomly distributed to observation for 3 weeks (n=10) or 6 weeks (n=10). Under general anesthesia, an elliptical area (major axis from 1st to 20th ring and minor axis 40% of tracheal diameter) was resected and the stumps were sutured. The internal and external diameters were measured (before and after the observation time) and the stenosis index was calculated. Blood samples were collected (gasometry, hematocrit and hemoglobin.) before and after the surgical proceedings. RESULTS The weight was significant lower in the animals of 6 weeks (15,551+/-3286.2) in comparison with those of 3 weeks observation (17,250+/-3575.0). No significant differences were noted in the extension of the trachea on the 21st day (21.2+/- 1.8) or 42nd day (21.1+/-1.7). The mean (40.1) and the median (40.5) of rings counted on the 21st day were quite similar to mean (38.1) and median (39.0) that were counted on the 42nd day. In the animals of group A (3 weeks) the mean (46.8%) and the median (49.8%) of index stenosis showed no significant difference (Mann Whitney test p<0.001) in comparison with the mean (55.1%) and median (52.4%) of the animals from group B (6 weeks). No mechanical or biochemical distresses were recorded through all period of observation. CONCLUSION The surgical proceeding was effective to promote a model of longitudinal and extensive tracheal stenosis.

Estudo da ação dos fios de categute cromado e poliglecaprone 25, na ileocistoplastia em ratos, destacando a formação de cálculos

Realizou-se um estudo da acao dos fios de categute cromado 6-0 e de poliglecaprone 25, 5-0, para determinar o fio ideal na ileocistoplastia em ratas. O maior objetivo, foi a profilaxia litiasica. Utilizaram-se 51 ratos de Wistar, que participaram de dois grupos experimentais: grupo do plano piloto (27 ratos), que foi o grupo categute (GC) e grupo da tese do mestrado (24 ratos), que foi o grupo poliglecaprone (GP). Sob anestesia intraperitonial com pentobarbital sodico a 3%, todos os animais foram submetidos a ileocistoplastia, apos laparotomia mediana longitudinal. Nos ratos do GC, a anastomose da bexiga urinaria (aberta 0,5 cm sagitalmente no seu apice), com a extremidade distal do segmento ileal ,era realizada por meio de pontos separados em plano unico, com fio de categute cromado 6-0, e nas ratas do GP, com fio de poliglecaprone 25, 5-0. Seguiu-se a sintese da parede abdominal e recuperacao anestesica. O estudo era realizado em 27, 42 e 57 dias nos animais do GC, que eram divididos em 3 subgrupos de 9 ratos. No GP, os animais eram analisados em 28 e 84 dias, por subgrupos de 12 animais. Transcorrido o tempo determinado para cada subgrupo, eram reoperados e observados os aspectos macroscopicos da cicatrizacao, aderencias e formacao de calculos. A bexiga urinaria ampliada pelo segmento ileal, era ressecada, aberta, lavada em solucao salina isotonica, fixada no Liquido de Bouin, e processada , para histologia. A eutanasia era consumada com dose minima letal anestesica. Os resultados apresentados, foram 29,6% de litiase, nas ratas do GC: 5,4% em 27dias; 10% em 42 dias e 14,25 em 57 dias do pos operatorio (p.o.). Nas ratas do GP, nao foram encontrados calculos. Os estudos microscopicos, foram submetidos a analise estatistica (a £ a 0,05), e utilizados para outro trabalho cientifico. Conclui-se: na ileocistoplastia com categute cromado 6-0, ha 29,6% de calculos, do 27o ao 57o dia p.o. e com o uso do fio de poliglecaprone 25, 5-0, ate o 84o p.o.,nao ha presenca de litiase.

ENXERTO DE FÁSCIA LATA AUTÓGENA EM FERIMENTOS PENETRANTES PROVOCADOS NO ESÔFAGO CERVICAL DE CÃES

The aim of this study was to study the efficiency of autogenus graft of fascia lata to treat experimental wounds at the cervical level of esophagus of dogs. Two operative procedures were used in forty dogs in order to correct the injuries and compared among the groups. The standard area of the injury ranged was 3,12 cm square. The animals were divided in two groups of 20 each, so-called Group A ( suture group ) and Group B ( graft groups ). Group A and B were subdivided in two another group, so-called Group A1 A2 and B1,B2 with 10 animals each one with the pourpose of reoperation at seventh and thirtieth past operatives days. The Group A, so-called Control Group was undergone a techinique of extramucous suture with simple points of nylon on transversal plan of esophagus axis. On Group B, so-called Experimental Group it was employed autogenos graft of fascia lata in order to oclud the penetrating injury. The grafts was sutured on the esophagus wal by extramucous technique with the nylon . Macroscopic and microscopic results were compared among the two groups by invariate analysis. No statistical significant differences were observed among the groups besides the animals of Group A had showed a good clinical behavior and lower incidence of fistulae. However on Group B ( undergone a fascia lata graft ) had shouwed five cases of fistulae. In conclusion, the fascia lata not appear to be useful for treat penetrating wounds at the cervical level of esophagus in dogs.

Efeito do enxerto autólogo de pericôndrio costal com butil-2-cianoacrilato em lesão provocada na cartilagem articular do joelho de coelhos

The purpose of this study was to verify the effect of the perichondrium graft with butyl-2-cyanoacrylate in provoked injury in the articular cartilage of rabbit`s knee. Male adult animals were used, divided in 2 groups, called Group A and Group B, with 17 animals each. The Group A animals were reoperated in 4 weeks and the Group B animals in 8 weeks. A 2 cm fragment was taken out from the 7th costal cartilage from which the perichondrium was removed. Two osteo-cartilaginous cylinders were taken out from each medialis condyles of the femurs in the same animal. The articular cartilage of the cylinder was replaced in one side by the perichondrium with a thin layer of sticking-tissue in its external face and only the articular cartilage was removed from the other side. The cylinders were replaced in the femurs. Macroscopically, in Group A, most of the injuries which received the perichondrium were found completely covered with tissue and all the lesions without perichondrium were only partilly covered. In Group B, no macroscopic significant difference in the covering of the injuries was found. Statistically, There was no microscopical significant difference between the injuries with and without perichondrium of the Group A and Group B and neither groups A and B.

Estudo dos efeitos das ressecções colônicas parciais em ratos

UNLABELLED In order to study the effects of partial colectomy, 30 rats Wistar were divided into three groups: GI and GII had the cecun and the ileo cecal valve resected and proximal colectomy was performed in GI and distal in GII. GIII had distal colectomy without cecum resection. The length of the remain colon was of 5 cm in all groups. Colostomy was performed in GI, GII and GIII. Parameters evaluated: body weight, fecal composition concerning to water, lipids and proteins on preoperative time and on the 10th, 20th, 30th, 40th, 50th and 60th days of postoperative time. All statistical tests were conducted at a 5% two-sided risk level. The evaluation was made by analysis of variance techniques. CONCLUSIONS Concerning to body weight, there is no significant difference on the late postoperative time in any group or when comparing the three groups on this same period. On late postoperative time, GI and GII had a large amount of fecal water, lipids and proteins when compared to the preoperative time and to GIII. On the 60th day theres no significant difference on the quantity of fecal water when comparing the three groups and the same occurs on the 50th day when considering the quantity of fecal proteins.In order to study the effects of partial colectomy, 30 rats Wistar were divided into three groups: GI and GII had the cecun and the ileo cecal valve resected and proximal colectomy was performed in GI and distal in GII. GIII had distal colectomy without cecum resection. The length of the remain colon was of 5 cm in all groups. Colostomy was performed in GI , GII and GIII. Parameters evaluated: body weight, fecal composition concerning to water, lipids and proteins on preoperative time and on the 10th, 20th, 30th, 40th, 50th and 60thdays of postoperative time. All statistical tests were conducted at a 5% two-sided risk level. The evaluation was made by analysis of variance techniques. Conclusions: Concerning to body weight, there is no significant difference on the late postoperative time in any group or when comparing the three groups on this same period. On late postoperative time, GI and GII had a large amount of fecal water, lipids and proteins when compared to the preoperative time and to GIII. On the 60th day theres no significant difference on the quantity of fecal water when comparing the three groups and the same occurs on the 50th day when considering the quantity of fecal proteins.

Avaliação da concentração das fibras do tecido conjuntivo quando da associação de poliglactina 910 e silicone: estudo experimental em ratos

It is an important area of investigation the choice of an adequate substance for the fixation of silicon prosthesis without generating a lot of fibrotic tissue reaction. We have studied the tissue reaction after the implantation of silicon prosthesis with polyglactin 910 threads. Silicon grids measuring 1,5 x 1,5cm and thickness of 0,7mm were implanted under the subcutaneous tissue of rats. The animals were studied 30, 60 and 90 days after implantation. Then they were sacrificed. The grids and the adjacent tissue were excised. The time did not interfere with the number of colagen fibers in sub-groups. Quantity of colagen fibers were not different amoung the sub-groups of 30, 60 and 90 days. With or without poliglactin 910. In the group of pure silicon grids we have found a significant difference among the reticular fibers. The great number was observed in the 30 and 60 days groups if compared with the group of 90 days. The polyglactin 910 with the silicon grid not change the amount of connective tissue fibers in the grid¢s fenestrations.