Evaluation of mesalazine polymeric conjugate in the treatment of actinic proctitis in rats.

PURPOSE: The present study aimed at testing a new formulation of mesalazine linked to chondroitin sulfate and its components alone in the treatment of actinic proctitis in rats. METHODS: Forty-seven female Wistar rats were submitted to pelvic radiation and divided into eight groups: control A, mesalazine A, chondroitin A, and conjugate A, gavage of the according substance two weeks after irradiation and sacrifice three weeks after oral treatment; control C, mesalazine C, chondroitin C, and conjugate C, sacrifice six weeks after oral treatment. The rectum was submitted to histological characterization for each of the findings: inflammatory infiltrate, epithelial degeneration, mucosal necrosis, and fibrosis. RESULTS: The inflammatory infiltrate was more intense in chondroitin A, mesalazine A, and conjugate C. The collagen deposition was less intense in chondroitin A, and mesalazine A, and more intense in control C. CONCLUSIONS: Mesalazine and chondroitin alone were efficacious in inducing a delayed inflammatory response, hence reducing the late fibrosis. The conjugate was able to induce an ever more delayed inflammatory response.

Evaluation of mesalazine polymeric conjugate in the treatment of actinic proctitis in rats

ABSTRACT Purpose: The present study aimed at testing a new formulation of mesalazine linked to chondroitin sulfate and its components alone in the treatment of actinic proctitis in rats. Methods: Forty-seven female Wistar rats were submitted to pelvic radiation and divided into eight groups: control A, mesalazine A, chondroitin A, and conjugate A, gavage of the according substance two weeks after irradiation and sacrifice three weeks after oral treatment; control C, mesalazine C, chondroitin C, and conjugate C, sacrifice six weeks after oral treatment. The rectum was submitted to histological characterization for each of the findings: inflammatory infiltrate, epithelial degeneration, mucosal necrosis, and fibrosis. Results: The inflammatory infiltrate was more intense in chondroitin A, mesalazine A, and conjugate C. The collagen deposition was less intense in chondroitin A, and mesalazine A, and more intense in control C. Conclusions: Mesalazine and chondroitin alone were efficacious in inducing a delayed inflammatory response, hence reducing the late fibrosis. The conjugate was able to induce an ever more delayed inflammatory response.

Development of a new model of actinic enteritis in rats using a cobalt-60 open source and a protection device as a collimator.

PURPOSE:: To describe a new model of actinic enteritis that does not use radiotherapy machines. METHODS:: Sixteen Wistar rats were divided into four groups, consisting of four animals each: control (group A), two weeks after irradiation (group B), five weeks after irradiation (group C) and eight weeks after irradiation (group D). Animals were given a 10Gy radiation from a Cobalt-60 natural source in a nuclear technology research center. Protections of the surrounding tissues were obtained through the usage of plumb devices with a hole in the center, which served as a collimator. We obtained irradiated and non-irradiated colons from each animal. RESULTS:: In group B we found an important inflammatory response in the irradiated colon, which appeared in a reduced way in group C and was minimal in group D, in which we found a relevant collagen submucosal deposition/fibrosis. In all groups, the non-irradiated colon had a lower pathological damage in comparison with the irradiated colon. CONCLUSION:: We thus described an efficient and feasible technique for obtaining an animal model of actinic enteritis.

Development of a new model of actinic enteritis in rats using a cobalt-60 open source and a protection device as a collimator

Abstract Purpose: To describe a new model of actinic enteritis that does not use radiotherapy machines. Methods: Sixteen Wistar rats were divided into four groups, consisting of four animals each: control (group A), two weeks after irradiation (group B), five weeks after irradiation (group C) and eight weeks after irradiation (group D). Animals were given a 10Gy radiation from a Cobalt-60 natural source in a nuclear technology research center. Protections of the surrounding tissues were obtained through the usage of plumb devices with a hole in the center, which served as a collimator. We obtained irradiated and non-irradiated colons from each animal. Results: In group B we found an important inflammatory response in the irradiated colon, which appeared in a reduced way in group C and was minimal in group D, in which we found a relevant collagen submucosal deposition/fibrosis. In all groups, the non-irradiated colon had a lower pathological damage in comparison with the irradiated colon. Conclusion: We thus described an efficient and feasible technique for obtaining an animal model of actinic enteritis.

Neutrophilic infiltration in lungs of mice with peritonitis in acid or basic medium.

BACKGROUND: Bacterial peritonitis is associated with systemic complications such as pneumonia. OBJECTIVE: To determine in an experimental model of peritonitis whether the pH of peritoneal fluid infection influences the influx of neutrophils into the lung, and whether treatment outcome would be similar in peritonitis with liquid at any pH. MATERIALS AND METHODS: We studied 48 mice with peritonitis induced by cecal ligation and puncture. The animals were distributed randomly into three groups: the first one had an injection into the peritoneal cavity with saline, pH 7.0; the second group was injected with saline, pH 8.0; and the third group with saline, pH 3.0. After 2 hours, half the animals in each group was treated by washing the abdominal cavity with warm saline solution and administration of ceftriaxone every 12 hours, and half of each group was killed by anesthetic overdose, and lung biopsy was done. The animals kept in treatment were killed 24 hours after treatment, and lung biopsy was also performed. The samples were stained with H&E and the number of neutrophils in 20 areas was checked. The mean number of cells in each group was compared between groups and with an untreated one. RESULTS: The group with peritonitis associated with alkaline solution showed a higher population of neutrophils during untreated peritonitis (P = 0.04). The response to treatment by lavage of the peritoneal cavity and antibiotics was more effective in reducing the population of neutrophils in the group with peritonitis at pH 8.0, unlike that observed in animals with peritonitis at pH 3.0 (P = 0.03). CONCLUSION: Peritonitis associated with lower pH solution, despite the lower influx of leukocytes in the first two hours after installation of peritonitis, was not able to reduce the population of these cells in mice's lung in response to standard therapy.

Clinical Factors Associated with Cutaneous Cerebrospinal Fluid Leakage in Infants Who Underwent a Ventriculoperitoneal Shunt Surgery / Fatores clínicos associados a fístula liquorica cutânea em lactentes submetidos a derivação ventriculoperitoneal

Objective The aim of the study is to determine the factors related to fetal maturity and clinical parameters that may be involved in the development of skin cerebrospinal fluid leakage. Methods This study evaluated 72 infants undergoing ventriculoperitoneal (VP) shunt between 2004 and 2008 at the Odilon Behrens Municipal Hospital. All children were treated by the same surgeon, and the clinical data concerning weight, age, and percentile, as well as hemoglobin levels, were collected from medical records and duly noted in proper protocols. Results A tendency toward a high incidence of fistula could be observed in children born with a weight percentile of less than 10 (p » 0.06), and an even higher incidence could be identified in children who underwent surgery before 1 month of life (p < 0.05). Other parameters showed no significant difference in the comparison between children with and without cerebrospinal leakage. Conclusion The chronological age and the degree of intrauterine nutrition are determining factors in cerebrospinal fluid leakage in infants and may well influence the incidence of wound complications after a VP shunt.

Determinar fatores clínicos e de maturidade fetal que possam estar envolvidos no desenvolvimento de fístulas cutâneas pós-operatórias. Métodos Foram avaliados 72 lactentes submetidos a derivação ventriculoperitoneal no Hospital Municipal Odilon Behrens no período de 2004 a 2008. Os dados clínicos elaboratoriais ao nascimento e à cirurgia foram coletados dos prontuários e anotados em protocolos próprios. Resultados Houve uma tendência a ocorrência de fístulas em crianças nascidas com percentil de peso abaixo de 10 (p » 0,06) e maior incidência em crianças operadas antes de um mês de vida (p < 0,05). Os demais parâmetros não foram significativos. Conclusão A idade cronológica e o grau de nutrição intrauterina são fatores envolvidos na formação de fístulas liquóricas em recém-nascidos, tendo impacto na prevalência de complicações nas feridas de lactentes submetidos a derivação ventriculoperitoneal.

Amniotic membrane as a biological dressing in infected wound healing in rabbits.

PURPOSE: To investigate amniotic membrane as a biological dressing in infected wound healing in rabbits. METHODS: The use of preserved amniotic membranes (AMs) was examined using 15 rabbits with experimentally induced wound infections on their backs. Healing was histologically evaluated during different phases including inflammation, granulation, epithelialization, and fibroplasia. The animals were distributed into three groups for histological study at seven, 14, 21, and 28 days post-wound induction. Group A did not receive treatment: the wound was left exposed and dry; Group B received a daily exposure treatment with collagenase; and Group C received one AM, which also remained exposed. RESULTS: A marked reduction of the inflammatory phase was observed in Group C at 21 days, and the granulation phase of this healing increased at 14 days. Epithelialization was similar among the three groups, and fibroplasia was more pronounced in Group C at 14 days. Furthermore, gradual collagen organization also began for the animals in Group B at 14 days. CONCLUSION: The amniotic membrane did not significantly alter the inflammation, epithelialization, or fibroplasia phases but did increase angiogenesis up to Day 14 compared with the dry dressing and collagenase treatments.

Amniotic membrane as a biological dressing in infected wound healing in rabbits

PURPOSE: To investigate amniotic membrane as a biological dressing in infected wound healing in rabbits. METHODS: The use of preserved amniotic membranes (AMs) was examined using 15 rabbits with experimentally induced wound infections on their backs. Healing was histologically evaluated during different phases including inflammation, granulation, epithelialization, and fibroplasia. The animals were distributed into three groups for histological study at seven, 14, 21, and 28 days post-wound induction. Group A did not receive treatment: the wound was left exposed and dry; Group B received a daily exposure treatment with collagenase; and Group C received one AM, which also remained exposed. RESULTS: A marked reduction of the inflammatory phase was observed in Group C at 21 days, and the granulation phase of this healing increased at 14 days. Epithelialization was similar among the three groups, and fibroplasia was more pronounced in Group C at 14 days. Furthermore, gradual collagen organization also began for the animals in Group B at 14 days. CONCLUSION: The amniotic membrane did not significantly alter the inflammation, epithelialization, or fibroplasia phases but did increase angiogenesis up to Day 14 compared with the dry dressing and collagenase treatments. .

Use of alloplastic meshes in abdominal wounds of rats with induced peritonitis.

BACKGROUND: The use of alloplastic meshes has been historically contra-indicated in patients with infection. AIM: To evaluate the use of polypropylene meshes in the treatment of abdominal wall defects in rats with peritonitis. METHODS: Twenty Wistar female rats were divided into two groups: induction of peritonitis (test group) and without peritonitis (control group). An abdominal wall defect was created in all animals, and polypropylene mesh was applied. The evaluation of the tensile strength of the mesh was carried out using tensiometer and microscopic analysis of the healing area was done. RESULTS: More adhesion of the mesh to the rat abdominal wall was observed in test group. The histopathological analyses showed prevalence of moderate to accentuated granulation tissue in both groups, without significant differences. CONCLUSION: The use of the mesh coverage on abdominal wall defects of rats with induced peritonitis did not show worse results than its use in healthy animals, nor was its integration to the resident tissue any worse.

Use of alloplastic meshes in abdominal wounds of rats with induced peritonitis / Uso de telas inorganicas em feridas abdominais de ratos com peritonite induzida

Background : The use of alloplastic meshes has been historically contra-indicated in patients with infection. Aim : To evaluate the use of polypropylene meshes in the treatment of abdominal wall defects in rats with peritonitis. Methods : Twenty Wistar female rats were divided into two groups: induction of peritonitis (test group) and without peritonitis (control group). An abdominal wall defect was created in all animals, and polypropylene mesh was applied. The evaluation of the tensile strength of the mesh was carried out using tensiometer and microscopic analysis of the healing area was done. Results : More adhesion of the mesh to the rat abdominal wall was observed in test group. The histopathological analyses showed prevalence of moderate to accentuated granulation tissue in both groups, without significant differences. Conclusion : The use of the mesh coverage on abdominal wall defects of rats with induced peritonitis did not show worse results than its use in healthy animals, nor was its integration to the resident tissue any worse. .

Racional: O uso de telas inorgânicas historicamente é contra-indicado em paciente com infecções. Objetivo : Avaliar o comportamento e cicatrização de paredes abdominais com uso de telas de polipropileno após infecções intra-cavitárias. Método : Foram estudadas 20 ratas Wistar aleatoriamente divididas nos grupos Estudo (com peritonite) e Controle (sem peritonite). Um defeito na parede abdominal foi criado em todos os animais, onde foi aplicada tela de polipropileno. Foi feita avaliação da força de tensão com uso de tensiômetro, além de análise histológica da área cicatricial. Resultados : Observou-se maior adesividade da tela às paredes dos animais do grupo Estudo quando comparado ao grupo Controle. A análise histopatológica mostrou prevalência de tecido de granulação de acentuado à moderado em ambos os grupos, sem diferença significativa. Conclusão : O uso de telas inorgânicas nos defeitos da parede abdominal em ratos com peritonite induzida não mostrou resultado pior do que aquele obtido de animais sem infecção, tanto em relação à sua integração quanto ao tecido cicatricial no defeito da parede abdominal. .

Chlorhexidine as a factor that promotes peritoneal adhesions in rats with induced peritonitis.

PURPOSE: To investigate the effects of chlorhexidine on the formation of adhesions and dilation of the colon at the oral end of anastomosis in the presence of peritonitis. METHODS: Peritonitis was induced in male Wistar rats by cecal ligation and puncture (CLP). Abdominal cavities were irrigated with tepid solutions containing 0.9% saline (SAL group; n=8) or 0.05% chlorhexidine (CHD group; n=8), after which colon anastomoses were performed. Control rats (n=8) were submitted to colon anastomoses but not to CLP. Animals were euthanised seven days after surgery and the incidence of adhesions, the degree of dilation of colon loops and an index were calculated to determine variables correlation. RESULTS: No animals exhibited macroscopic signs of residual peritonitis or abdominal abscesses. Adhesions were observed in 75% of control and 100% of SAL and CHD animals. Dilation of intestinal loops at the oral end of anastomosis was observed in control (50%), SAL (57.2%) and CHD (66.7%) animals. The calculated index was 1.25 in group A; 1.86 in group B; and 2.0 group C. CONCLUSION: Chlorhexidine promoted stronger adhesions and a greater dilatation of colonic loops than control group.

Clorhexidine as a factor that promotes peritoneal adhesions in rats with induced peritonitis

PURPOSE: To investigate the effects of chlorhexidine on the formation of adhesions and dilation of the colon at the oral end of anastomosis in the presence of peritonitis. METHODS: Peritonitis was induced in male Wistar rats by cecal ligation and puncture (CLP). Abdominal cavities were irrigated with tepid solutions containing 0.9% saline (SAL group; n=8) or 0.05% chlorhexidine (CHD group; n=8), after which colon anastomoses were performed. Control rats (n=8) were submitted to colon anastomoses but not to CLP. Animals were euthanised seven days after surgery and the incidence of adhesions, the degree of dilation of colon loops and an index were calculated to determine variables correlation. RESULTS: No animals exhibited macroscopic signs of residual peritonitis or abdominal abscesses. Adhesions were observed in 75% of control and 100% of SAL and CHD animals. Dilation of intestinal loops at the oral end of anastomosis was observed in control (50%), SAL (57.2%) and CHD (66.7%) animals. The calculated index was 1.25 in group A; 1.86 in group B; and 2.0 group C. CONCLUSION: Chlorhexidine promoted stronger adhesions and a greater dilatation of colonic loops than control group.

Cicatrização do cólon após mucosectomia mecânica e sutura evertente em ratos / Healing of colon after mechanic mucosectomy and evertent suture in rats

A mucosectomia é utilizada durante a confecção de reservatórios ileais nas proctocolectomias por doença inflamatória intestinal. Entretanto, tem-se relatado aumento da incidência de obstruções intestinais em pacientes submetidos ao procedimento, sendo que o contato de uma grande área de submucosa poderia ser responsável pela ocorrência de estenoses, além de poder relacionar-se com aumento da pressão de ruptura desses segmentos. Com o objetivo de avaliar as alterações macroscópicas após a mucosectomia e a pressão de ruptura desses segmentos, foram estudados 16 ratos Holtzman distribuídos em dois grupos: A (n=8), anastomose colo-cólica em plano único extramucoso invertente com pontos separados de fio absorvível e B (n=8), mucosectomia e anastomose colocólica em plano único evertente com pontos separados de fio absorvível. No terceiro dia pós-operatório, foram estudadas as alterações macroscópicas e a pressão de ruptura dos segmentos colônicos contendo as anastomoses. Os resultados obtidos mostraram aumento na incidência e intensidade das aderências peritoneais nos animais do grupo B (p=0,01), incidência de 100% de estenoses das anastomoses, sem que ocorresse qualquer estenose no grupo A (p=0,01) e aumento não significativo na pressão de ruptura das anastomoses no grupo B (4,3 ± 2,4 mmHg vs. 10,5 ± 8,2 mmHg). Concluindo, a mucosectomia aumentou a reação inflamatória tecidual, sendo causa não só de aumento na pressão de ruptura como na incidência de estenoses de anastomoses colônicas de ratos.

The mucosectomy is used during the making of the ileal pouch in proctocolectomy due to inflammatory bowel disease. However, there are reports of increased incidence of intestinal obstructions in patients undergoing the procedure, when the contact of a large submucosal area could be responsible for the stenosis, and can relate to the increase of burst pressure of these segments. To evaluate the macroscopic alterations after the mucosectomy and the burst pressure of these segments, 16 Holtzman rats were studied divided into two groups: A (n = 8), colo-colic anastomosis in extra mucosal single invertent plan with separate absorbable sutures and B (n = 8), mucosectomy and colo-colic anastomosis in a single evertent plane with separate absorbable sutures. On the third post-operatory day the macroscopic alterations and burst pressure of the colony segments containing the anastomosis were studied. The found results showed increase in the incidence and intensity of peritoneal adherences in the animals of group B (p=0,01), incidence of 100% of the anastomosis steanosis, with no occurrence of stenosis in the group A (p=0,01), and no significant increase in the burst pressure in the group B (4,3 ± 2,4 mmHg vs. 10,5 ±8,2 mmHg). Conclusion : the mucosectomy increased the tissue inflammatory reaction, giving cause to the increase of the burst pressure as well as the incidence of colonic anastomosis steanaosis in rats.

Anastomoses colônicas após mucosectomia química, em ratos / Colonic anastomosis after chemical mucosectomy in rats

Objetivo: Avaliar, experimentalmente, os efeitos da mucosectomia química sobre a cicatrização de anastomosescolônicas. Metodologia: Estudou-se 17 ratos Wistar machos divididos nos seguintes grupos: A (n=12), anastomose colônica; B (n=13), anastomose colônica após mucosectomia. A mucosectomia foi realizada através da introdução de um bastão de nitrato de prata a 10%, durante um minuto, através das duas bocas a serem anastomosadas, e as anastomoses realizadas em plano únicototal, evertente, com fio polivicril 6-0 em pontos separados. Os animais foram estudados após 7 dias (6 do grupo A1 e 6 do grupo B1) e 14 dias (7 do grupo A2 e 6 do grupo B2) da cirurgia, e realizadas observações macroscópicas da presença de aderências, fístulas (saída de secreção através da anastomose ou teste da pressão de ruptura igual a zero), estenose (dilatação intestinal proximal à anastomose), abscessos peri-anastomóticos e peritonite. Foi também avaliada a pressão de ruptura das anastomoses e histologia das anastomoses. Os resultados qualitativos foram avaliados pelo teste do Qui-quadrado (com correção de Yates) e osquantitativos através do teste de Kruskall-Wallis, sendo considerados significativos valores de p<0,05. Resultados: Nenhum dos animais estudados apresentou fístulas. A incidência de aderências peri- anastomóticas não foi diferente entre os grupos (A1=100%, B1=100%, p=N.S.; A2=75%, B2=50%, p=N.S.). Houve semi-obstrução da anastomose em 25% dos animais do grupo A1, 50% daqueles do grupo B1, 25% dos animais do grupo A2 e 50% dos animais do grupo B2, sem diferença significativa entre os grupos.A pressão de ruptura, em mmHg, foi de 27,0 ± 4,5 no grupo A1, 34,5 ± 2,0 no grupo B1, 28,9 ± 4,2 no grupo A2 e 24,0 ± 3,4 no grupo B2, com aumento significativo no grupo B1 quando comparados aos grupos A1 (p=0,03) e B2 (p=0,02)...

Objective: To evaluate, experimentally, the effects of chemical mucosectomy on colon healing in rats. Methods: We studied 17 male Wistar rats divided into following groups: A (n=12), colonic anastomosis; B (n=13), colonic anastomosis after use of 10% silver nitrate. The mucosectomy in group B was made by means introduction of 10% silver nitrate pencil into anastomotic surfaces during 1 minute in an extension of 0.5 cm. The anastomosis was made in single plane with evertent sutures of polyvicryl 6-0 in separated sutures. The animals were evaluated in the seventh postoperative day (A1, 6 of the group A and B1, 6 of the group B) and fourth postoperative day (A2, 7 of the group A and B2, 6 of the group B). The anastomosis was evaluated in macroscopic aspect (adherence, fistula, stenosis, perianastomotic abscesses, peritonitis), rupture pressure (mmHg) and histology (inflammatory infiltrate). The data were analysed by Chi-square test (qualitative data) and ANOVA (quantitative data), and considered significative values of p<0.05. Results: None animal presented fistula. The incidence of adherence was no different among the groups. (A1=100%, B1=100%, p= NS; A2=75%, B2=50%, p= NS). There were anastomosis partial obstruction in 25% of group A1, 50% inB1, 25% in A2 and 50% in B2, without significant differences among the groups. The rupture pressure was 27,0 ± 4,5 in A1 group, 34,5 ± 2,0 in B1 group, 28,9 ± 4,2 in A2 group and 24,0 ± 3,4 in group. There was an significant increase in pressure rupture in B1 group when compared with A1 group (p=0,03) and B2 group (p=0,02). Conclusion: The chemical mucosectomy with silver nitrate was not associated with increase in postoperative cicatricial complications in wound colon healing in rats. There was, however, an increase in anastomosis strength in early period of the cicatricial process, without influence in latter period.

Clinical and histological responses to laparoscopically-induced peritonitis in rats / Resposta clínica e histológica à indução de peritonite via laparoscopia em ratos

PURPOSE: To evaluate the efficacy of inducing peritonitis in rats through laparoscopic cecal ligation (CL), by means of an elastic band. METHODS: Twelve Wistar rats were subjected to cecal ligated with an elastic band applied using a specially constructed applicator. In six of the animals (the CL group) the cecal sac was preserved intact whilst in the remaining animals (the CLP group) the sac was perforated with scissors. Clinical parameters, characteristics of the peritoneal cavity and cecum, and histological features of the cecal tissue were observed in all experimental animals 8 and 24 h after surgery. RESULTS: CLP animals exhibited at least one clinical sign of sepsis within the first 8 h of observation. The peritoneal liquid was observed to be clear in almost all members of the CLP. Polymorphonucleated cells were detected in the tunica serosa of the cecum of CLP animals. In contrast, all members of the CL group were alive after 24h, and of polymorphonucleated cells in the muscle layer of the cecal wall were observed. The presence of peritoneal liquid was not detected in CL animals. CONCLUSION: Although elastic ligation of the cecum was reproducible, puncture of the cecal sac was essential for induction of sepsis.

OBJETIVO: Avaliar a eficácia de induzir peritonite em ratos através da ligadura cecal laparoscópica (CL), por meio de banda elástica. MÉTODOS: Doze ratos Wistar foram submetidos a ligadura cecal com banda elástica aplicada com dispositivo especialmente construído para este fim. Em seis animais (grupo CL), a bolsa cecal foi mantida intacta, enquanto nos outros animais (grupo CLP), a bolsa foi perfurada com tesoura. Parâmetros clínicos, características da cavidade peritonial e ceco, e histologia do tecido cecal foram examinados em todos os animais 8 e 24 horas após a cirurgia. RESULTADOS: Os animais do grupo CLP apresentaram pelo menos um sinal clínico de sepses nas primeiras 8 h de observação. Líquido peritonial claro foi observado em quase todos os membros do grupo CLP. Leucócitos polimorfonucleares foram identificados na serosa do ceco dos animais do grupo CLP. Por outro lado, todos os animais do grupo CL estavam vivos após 24 h, e leucócitos polimorfonucleares estavam restritos à muscular própria. Presença de líquido peritonial não foi detectada nos animais do grupo CL. CONCLUSÃO: A ligadura elástica do ceco foi reprodutível e a secção da bolsa cecal foi essencial para a indução de sepse.

Clinical and histological responses to laparoscopically-induced peritonitis in rats.

PURPOSE: To evaluate the efficacy of inducing peritonitis in rats through laparoscopic cecal ligation (CL), by means of an elastic band. METHODS: Twelve Wistar rats were subjected to cecal ligated with an elastic band applied using a specially constructed applicator. In six of the animals (the CL group) the cecal sac was preserved intact whilst in the remaining animals (the CLP group) the sac was perforated with scissors. Clinical parameters, characteristics of the peritoneal cavity and cecum, and histological features of the cecal tissue were observed in all experimental animals 8 and 24 h after surgery. RESULTS: CLP animals exhibited at least one clinical sign of sepsis within the first 8 h of observation. The peritoneal liquid was observed to be clear in almost all members of the CLP. Polymorphonucleated cells were detected in the tunica serosa of the cecum of CLP animals. In contrast, all members of the CL group were alive after 24h, and of polymorphonucleated cells in the muscle layer of the cecal wall were observed. The presence of peritoneal liquid was not detected in CL animals. CONCLUSION: Although elastic ligation of the cecum was reproducible, puncture of the cecal sac was essential for induction of sepsis.

Bacterial colonization of the ileum in rats with obstructive jaundice

Qualitative and quantitative alterations in ileal flora during obstructive jaundice and the role of bile salts were evaluated in rats. Obstructive jaundice was associated with bacterial overgrowth in the ileum. This effect may be due to the reduced concentration of bile salts, since dietary supplementation reduced the small bowel aerobic bacterial flora.

As alterações qualitativas e quantitativas da flora ileal na obstrução biliar e o papel dos sais biliares foram avaliados em ratos. Em animais com obstrução biliar houve aumento da população ileal. Esse efeito é provavelmente causado pela ausência de sais biliares no lúmen ileal, uma vez que em animais cuja dieta foi suplementada com sais biliares houve redução da flora ileal.

Pulmonary phagocyte depression induced by an acid or alkaline solution in a rat model of peritonitis.

BACKGROUND: Peritonitis is a surgical problem with a high mortality rate attributable to various complications, including respiratory infection. This complication is more common under certain conditions reflective of the origin of peritonitis, suggesting that the composition of the peritoneal fluid exerts an influence on the intensity of the macrophage and peritoneal response. To establish a correlation among macrophage function, absorption of bacteria from the peritoneal cavity, and the pH of the peritoneal fluid, we carried out this study. METHODS: Thirty female Wistar rats were divided into three equal groups, all of which received infusions of 0.9% saline by parietal puncture. In group A (control), the saline pH was 7.0; in group B, it was 2.5; and in group C, it was 8.5. After 40 min, 0.25 mL of a suspension containing 10(11) colony-forming units of (99m)Tc-labeled Escherichia coli was infused by the same route. After another 40 min, samples of vena caval blood, spleen, liver, and lung were removed; the radioactivity was counted; bacterial absorption was determined; and the proportional radioactivity/g of tissue was calculated. The values were compared among the groups by the Student t-test, with the level of significance set at p < 0.05. RESULTS: There was significantly greater bacterial absorption in group B than in group C (p = 0.004) but no differences in the numbers of bacteria in the liver and spleen. Bacteria were significantly more numerous in the peripheral blood in group B than in groups A and C (p = 0.04 for both). Pulmonary phagocytosis was significantly reduced in group B compared with group A (p = 0.008) and group C (p = 0.005). CONCLUSION: Peritonitis associated with acidic conditions in the peritoneal cavity is correlated with a reduction in pulmonary phagocytosis and an increase in the numbers of nonphagocytized bacteria in the peripheral blood, possibly representing a direct or indirect cause of the higher incidence of pneumonia and sepsis in these individuals.

Increased gastric emptying induced by Helicobacter heilmannii type 1 infection in rats.

The association between Helicobacter pylori infection and gastric motility abnormalities is still controversial, partly because of the lack of an appropriate animal model. H. heilmannii type 1 (Hh1), a spiral bacterium that infects the stomach of both man and pigs, easily colonises and induces an inflammatory response in the gastric mucosa of rodents. For these reasons, the present study investigated the relationship between gastric motility in rats experimentally infected with Hh1 and correlated the results with serum gastrin and gastric somatostatin concentrations, as these hormones seem to be involved in gastric motility. Ten rats were inoculated with gastric mucus from an Hh1-positive pig and 10 animals with gastric mucus from an Hh1-negative pig (control group). After 56 days, gastric emptying was studied in vivo by scintigraphy. The animals were then killed, blood samples were collected for serum gastrin measurement, strips of the gastric wall were obtained for an in-vitro motor study and fragments of the gastric antrum were obtained for somatostatin content evaluation, Hh1 diagnosis and histological study. There was a significant increase in gastric emptying in the test group compared with the controls as demonstrated by the in-vivo and in-vitro studies. Serum gastrin levels were significantly higher and somatostatin levels were lower in the test group than in the controls. In addition, infected animals showed evidence of gastritis on histological examination. Gastric motility is altered in rats infected with Hh1, a fact possibly related to concurrent abnormalities of gastrin and somatostatin secretion.

Motility of the upper digestive tract after subtotal pancreatectomy (80 per cent) in rats

Patients with pancreatic insufficiency secondary to extensive resection or to chronic pancreatitis preent steatorrhea as a complication. This is attributed to the absence of pancreatic enzymes in the intestinal lumen, lack of chyme digestion, and malabsorption syndrome. Several factors such as enteric hormones and intestinal microbiota may after the digestive motor pattern. The enteric microbiota in particular may induce nutrient malabsorption. In order to evaluate gastrointestinal flora and motility in pancreatic insufficiency, a study was conducted on 10 female Holtzman rats divided into two groups: A (n=5), submitted to corpocaudal pancreatectomy (80 per cent), and B (n=5) not submitted to any surgical procedure. Twenty-one days after surgery, the animals were sacrificed and jejunal wash samples were collected for the study of aerobic bacteria, blood samples were collected for biochemical measurements, and seromuscular sections of the gastric fundus and of the jejunum were obtained for an in vitro motor study. The results obtained demonstrated that there was no significant difference between groups in terms of bacteriologic or biochemical parameters, or in terms of gastric motor function. However, there was a significant increase in affinity for acetylcholine and in maximum contraction in the jejunal loops of pancreatectomized animals. In conclusion, corpocaudal pancreatectomy (80 per cent) induced significant motor alterations in the jejunum, and these alterations may be consistent with the steatorrhea of patients with pancreatic insufficiency.