Abstract Purpose: To develop a new 24 hour extended liver ischemia and reperfusion (LIR) model analyzing the late biochemical and histopathological results of the isolated and combined application of recognized hepatoprotective mechanisms. In addition, we used a new stratification with zoning to classify the histological lesion. Methods: A modified animal model of severe hepatic damage produced through 90 minutes of segmental ischemia (70% of the organ) and posterior observation for 24 hours of reperfusion, submitted to ischemic preconditioning (IPC) and topical hypothermia (TH) at 26ºC, in isolation or in combination, during the procedure. Data from intraoperative biometric parameters, besides of late biochemical markers and histopathological findings, both at 24 hours evolution time, were compared with control (C) and normothermic ischemia (NI) groups. Results: All groups were homogeneous with respect to intraoperative physiological parameters. There were no losses once the model was stablished. Animals subjected to NI and IPC had worse biochemical (gamma-glutamyl transpeptidase, alkaline phosphatase, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, direct bilirubin, and total bilirubin) and histopathological scores (modified Suzuki score) compared to those of control groups and groups with isolated or associated TH (p < 0.05). Conclusion: The new extended model demonstrates liver ischemia and reperfusion at 24 hour of evolution and, in this extreme scenario, only the groups subjected to topical hypothermia, combined with ischemic preconditioning or alone, had better outcomes than those subjected to only ischemic preconditioning and normothermic ischemia, reaching similar biochemical and histopathological scores to those of the control group.

Abstract Purpose: To evaluate whether combining hypothermia and remote ischemic preconditioning (RIPC) results in protection from ischemia-reperfusion (IR). Methods: Thirty-two Wistar rats underwent right nephrectomy and were randomly assigned to four experimental protocols on the left kidney: warm ischemia (group 1), cold ischemia (group 2), RIPC followed by warm ischemia (group 3), and RIPC followed by cold ischemia (group 4). After 240 minutes of reperfusion, histological changes in the left kidney, as well as lipid peroxidation and antioxidant enzyme activity, were analyzed. The right kidney was used as the control. Serum creatinine was collected before and after the procedures. Results: RIPC combined with hypothermia during IR experiments revealed no differences on interventional groups regarding histological changes (p=0.722). Oxidative stress showed no significant variations among the groups. Lower serum creatinine at the end of the procedure was seen in animals exposed to hypothermia (p<0.001). Conclusions: Combination of RIPC and local hypothermia provides no renal protection in IR injury. Hypothermia preserves renal function during ischemic events. Furthermore, RIPC followed by warm IR did not show benefits compared to warm IR alone or controls in our experimental protocol.

Abstract Purpose: To evaluate whether their combination was more effective than either alone in decreasing renal damage due to ischemia/reperfusion (I/R) injury in rats. Methods: Thirty-two Wistar rats were assigned to four groups. Following right nephrectomy, their left kidneys were subjected to warm ischemia (IR), cold ischemia (TH+IR), intraperitoneal injection of 10 mg/kg melatonin (MEL+IR), or injection of 10 mg/kg melatonin followed by cold ischemia (MEL+TH+IR). Eight randomly assigned right kidneys constituted the control group. After 240 min of reperfusion, left nephrectomy was performed for histopathological evaluation, lipid peroxidation, and measurement of antioxidant enzyme activity. Serum was collected to measure urea and creatinine concentrations. Results: Histopathological damage induced by ischemia and reperfusion was more attenuated in the MEL+TH+IR group than in the MEL+IR and TH+IR groups (p<0.037). Superoxide dismutase activity was significantly higher (p<0.029) and creatinine (p<0.001) and urea (p<0.001) concentrations were significantly lower in the MEL+TH+IR group than in the MEL+IR and TH+IR groups. Conclusion: The combination of melatonin (MEL) and topical hypothermia (TH) better protects against renal I/R injury than does MEL or TH alone.

Abstract Purpose: Topical hypothermia and local ischemic preconditioning have been shown to reduce renal ischemia-reperfusion (I/R) injury individually. We examined whether combination of both strategies lessens renal I/R injury. Methods: Post right nephrectomy, 40 male Wistar rats were randomly assigned to five experimental protocols performed in the left kidney: topical hypothermia without ischemia (TH), warm ischemia (IR), ischemic preconditioning followed by warm ischemia (IPC+IR), cold ischemia (TH+IR), and ischemic preconditioning followed by cold ischemia (IPC+TH+IR). Eight randomly assigned right kidneys constituted the control group. After 240 min of reperfusion, the left kidney was retrieved to evaluate histological changes, lipid peroxidation and antioxidant enzymes activity. Serum was collected to evaluate urea and creatinine. Results: IPC+TH+IR group revealed no difference to any other group subjected to ischemia in relation to histological changes, lipid peroxidation and antioxidant enzymes activity. Creatinine was lower in IPC+TH+IR group compared with IPC+IR, but showed no difference compared to TH+IR group. Conclusions: Combination of local ischemic preconditioning (IPC) and topical hypothermia conferred no protection in renal I/R injury. Moreover, local IPC solely followed by warm ischemia impaired renal function more than warm ischemia alone.

Resumo Objetivos: Estimar a prevalência de dor nas costas em adolescentes do sexo feminino no ano letivo e verificar se esta dor nas costas está associada com fatores socioeconômicos, demográficos, antropométricos e comportamentais. Métodos: Inquérito epidemiológico com amostra representativa de 495 estudantes do sexo feminino do ensino médio regular diurno, com idade de 14 a 18 anos, da cidade de São Leopoldo, RS, Brasil. Os dados foram coletados através de um questionário auto-aplicável composto por questões fechadas, padronizado, codificado e testado. A análise bivariada incluiu o teste do qui-quadrado (x2) e o cálculo das razões de prevalência (α<0,05). Resultados: A prevalência de dor nas costas foi de 75,2%. As regiões mais acometidas foram dorso-lombar (30,4%) e lombar (27,7%). Entre as alunas com dor, 60,5% apontaram uma intensidade de média a muita dor e 21,2% relataram que a dor as impediu de realizar suas atividades normais do dia a dia. Em relação aos fatores associados, a dor foi mais prevalente nas alunas com sobrepeso/obesidade (RP = 1,246; IC95%: 1,137 a 1,366), nas que relataram mochila/bolsa escolar pesadas (RP = 1,187; IC95%: 1,073 a 1,314) e nas que adotavam uma postura incorreta ao pegar objetos do chão (RP = 1,138; IC95%: 1,031 a 1,256). Conclusões: A prevalência de dor nas costas foi alta e esteve associada com IMC, com o peso relatado da mochila/bolsa escolar e com a postura ao pegar objetos do chão.

Abstract Objective: To estimate the prevalence of back pain in adolescent girls, and determine whether this pain is associated with socioeconomic, demographic, anthropometric, and behavioral factors. Methods: This was an epidemiological survey with a representative sample of 495 female high school students, aged 14 to 18 years, in the municipality of São Leopoldo in the southern Brazilian state of Rio Grande do Sul. Data were collected through a self-administered questionnaire with closed, standardized, coded, and tested questions. Bivariate analysis included the chi-square test (x2) and calculation of prevalence ratios (α<0.05). Results: The prevalence of back pain was 75.2%. The thoracic-lumbar (30.4%) and lumbar (27.7%) regions of the spine were most affected. Among the students with pain, 60.5% reported the severity of their pain to be moderate to severe, and 21.2% reported that the pain prevented them from performing activities of daily living. Regarding associated factors, the pain was more prevalent in overweight/obese students (RP = 1.246, 95% CI: 1.137 to 1.366), who reported carrying a heavy school backpack/bag (PR = 1.187, 95% CI: 1.073 to 1.314) and those who had incorrect posture when picking up objects from the floor (PR = 1.138, 95% CI: 1.031 to 1.256). Conclusions: There was a high prevalence of back pain associated with body mass index, reported weight of the student's school backpack/bag, and posture when picking up objects from the floor.

PURPOSE: To evaluate whether topical renal hypothermia (TRH) at different levels of temperature has protective effects on lung tissue after renal I/R, through an analysis of organ histology and inflammatory markers in lung tissue. METHODS: Twenty-eight male Wistar rats were randomly allocated across four groups and subjected to renal ischemia at different levels of topical renal temperature: normothermia (no cooling, 37°C), mild hypothermia (26°C), moderate hypothermia (15°C), and deep hypothermia (4°C). To induce I/R, the vessels supplying the left kidney of each animal were clamped for 40 minutes, followed by reperfusion. After four hours, another procedure was performed to harvest the tissues of interest. TNF-α, IL-1β and myeloperoxidase activity were measured in lung tissue. Histological analysis was performed in hematoxylin and eosin-stained lung specimens. RESULTS: Induction of renal I/R under deep topical hypothermia resulted in a significant decrease in lung concentrations of TNF-α compared with normothermic I/R (p<0.05). A trend toward significant correlation was found between lung IL-1β concentration and intensity of hypothermia (Spearman r=−0.37; p=0.055). No difference was found in myeloperoxidase activity or histologic injury between groups. CONCLUSION: Topical renal hypothermia reduces activation of the inflammatory cascade in the lung parenchyma. However, tissue-protective effects were not observed.

PURPOSE:To design an animal model of ischemia-reperfusion (I/R) in kidneys and evaluate the role that predetermined ranges of local hypothermia plays on markers of stress-oxydative as well as on histologic sections. METHODS: Twenty eight male rats Wistar, under general anesthesia, undergone right nephrectomy (G0, control group) followed by left kidney ischemia during 40 min. Four temperatures groups were designed, with seven animals randomized for each group: normothermic (G1, ±37ºC), mild hypothermia (G2, 26ºC), moderate hypothermia (G3, 15ºC) and deep hypothermia (G4, 4ºC). Left kidney temperature was assessed with an intraparenchymal probe. Left nephrectomy was performed after 240 min of reperfusion. After I/R a blood sample was obtained for f2-IP. Half of each kidney was sent to pathological evaluation and half to analyze CAT, SOD, TBARS, NO3, NO2. RESULTS:Histopathology showed that all kidneys under I/R were significantly more injured than the G0 (p<0.001). TBARS had increased levels in all I/R groups compared with the G0 (p<0.001). CAT had a significant difference (p<0.03) between G1 and G4. Finally, no difference was found on SOD, NO3, NO2 nor on f2-IP. CONCLUSION: This model of I/R was efficient to produce oxidative-stress in the kidney, showing that 4ºC offered significant decrease in free radicals production, although tissue protection was not observed.

OBJETIVO: Avaliar as variações de temperatura corporal, pressão arterial média (PAM) em um novo modelo de isquemia e reperfusão hepático que utiliza Pré-condicionamento isquêmico e Hipotermia tópica. MÉTODOS: Ratos (n= 32) da raça Wistar foram divididos em 5 grupos: Controle (C), Isquemia normotérmica (IN), Hipotermia a 26°C (H), Pré-condicionamento isquêmico (PCI) e Hipotermia a 26°C com Pré-condicionamento isquêmico com hipotermia (H+PCI). As aferições da PAM e temperatura corporal foram realizadas em intervalos de 30 minutos. Os animais foram submetidos à isquemia hepática de 90 minutos e 120 minutos de reperfusão. Nos grupos H e H+PCI, o fígado foi isolado e resfriado por superfusão de solução fisiológica gelada. Nos grupos com PCI e H+PCI foram aplicados 10 minutos de isquemia e 10 minutos de reperfusão antes do insulto isquêmico maior. RESULTADOS: Não houve diferença na PAM e temperatura corporal entre os grupos durante todo o experimento. CONCLUSÃO: O presente modelo permite a aplicação de hipotermia local associada ou não ao PCI. Novos estudos para avaliar os possíveis efeitos sinergísticos destas ferramentas podem ser reproduzidos sem alterações significativas na macrohemodinâmica e temperatura corporal, ou seja, sob condições estáveis.

PURPOSE: Evaluation of the Mean Arterial Pressure (MAP) and body temperature changes in a new model of liver ischemia-reperfusion applying topical Hypothermia and Ischemic Preconditioning (IPC). METHODS: Rats (n= 32) were divided in 5 groups: Control (C), Normothermic Ischemia (NI), Ischemic Preconditioning (IPC), Hypothermia 26°C plus IPC (H+IPC) and Hypothermia 26°C (H). MAP and body temperature were recorded at 30 minutes intervals throughout the entire experiment. The study groups underwent 90 minutes partial hepatic ischemia followed by 120 minutes of reperfusion. The median and lateral left lobes were isolated and topical 26°C hypothermia was induced by superfusion of cooled saline solution in H+IPC and H groups. A 10 minutes protocol of ischemia and reperfusion was applied in the IPC and H+IPC groups before the major ischemic insult. RESULTS: There was no significant difference in MAP and body temperature means between the groups throughout the experiments. CONCLUSION: The present model allows the induction of topical hepatic hypothermia associated or not to IPC. New studies to evaluate the possible synergistic effects of these tools can be reproduced without significant changes in macrohemodynamics and body temperature, or in other words, under stable conditions.

OBJETIVO: O estresse oxidativo é um importante mecanismo responsável pela disfunção dos enxertos após transplante de fígado (TF). Sabe-se que níveis baixos de Glutationa reduzida (GSH) deixam os enxertos vulneráveis aos danos de reperfusão. O objetivo deste estudo foi avaliar as concentrações de GSH e da Glutationa oxidada (GSSG), os danos hepatocelulares e a função em enxertos ótimos e subótimos após TF. MÉTODOS: Foram realizadas biópsias em 33 pacientes imediatamente antes do implante e duas horas após a reperfusão, permitindo a determinação do GSH, GSSG e o cálculo do índice de stress oxidativo (GSH/GSSG). Foram medidas as transaminases hepáticas e as atividades da Protrombina (TP) e do Fator V para avaliação dos danos hepatocelulares e da função do enxerto, respectivamente. O dano histopatológico foi avaliado através de um índice de cinco parâmetros. RESULTADOS: Houve uma diminuição nos níveis de GSH (p<0.01) 0.323 ± 0.062 ìmol/g to 0.095 ± 0.01 ìmol/g and 0.371 ± 0.052 ìmol/g to 0.183 ± 0.046 ìmol/g) e aumento nos níveis de GSSG (0.172 ± 0.038 ìmol/g to 0.278 ± 0.077 ìmol/g and 0.229 ± 0.048 ìmol/g to 0.356 ± 0.105 ìmol/g) (p<0.05). Houve diminuição do GSH/GSSG (2.23 ± 0.31 to 0.482 ± 0.042 and 2.47 ± 0.32 to 0.593 ± 0.068). Nenhuma diferença entre os grupos ótimo e subótimo foi vista após duas horas de reperfusão. Os escores de danos histopatológicos foram maiores no grupo subótimo (6.46 ± 0.4 vs. 5.39 ± 1.1) (p<0.05) e mostraram correlação com o TP e fator V no grupo Ótimo (p<0.05). A análise multivariada apontou a esteatose como um fator de risco independente para a ocorrência de danos histopatológicos (p<0.05). CONCLUSÃO: Houve uma significativa depleção de GSH e formação de GSSG após a preservação em solução devido a um intenso estresse oxidativo nos enxertos ótimos e subótimos, porém estes níveis não se correlacionaram com a viabilidade dos enxertos.

PURPOSE: The oxidative stress is an important mechanism responsible for dysfunction after orthotopic liver transplantation (OLT). Glutathione (GSH) low levels after cold storage render the grafts vulnerable to reperfusion injury. Aim of this study was to evaluate GSH and oxidized glutathione (GSSG) liver concentrations, the hepatocellular injury and function in optimal and suboptimal grafts after human OLT. METHODS: Liver biopsies were taken in 33 patients before the implant and two hours after reperfusion, allowing determination of GSH, GSSG and oxidative stress ratio (GSH/GSSG). Serum transaminases, prothrombin activity (PT) and factor V were measured to evaluate injury and function respectively. Histopathological injury was analyzed by an index of five parameters. RESULTS: There was a decrease in GSH (p<0.01) after reperfusion (0.323 ± 0.062 ìmol/g to 0.095 ± 0.01 ìmol/g and 0.371 ± 0.052 ìmol/g to 0.183 ± 0.046 ìmol/g) in suboptimal and optimal groups, respectively. An increase of GSSG (p<0.05) occurred after reperfusion (0.172 ± 0.038 ìmol/g to 0.278 ± 0.077 ìmol/g and 0.229 ± 0.048 ìmol/g to 0.356 ± 0.105 ìmol/g) in suboptimal and optimal groups, respectively. A decrease (p<0.01) occurred in the GSH/GSSG ratio after reperfusion (2.23 ± 0.31 to 0.482 ± 0.042 and 2.47 ± 0.32 to 0.593 ± 0.068) in suboptimal and optimal groups, respectively. Histopathological injury scores were higher (p<0.05) in the suboptimal group than in optimal (6.46 ± 0.4 vs. 5.39 ± 1.1) and showed correlation with PT and factor V in the optimal group (p<0.05). Multivariate analysis pointed steatosis as an independent risk factor to histopathological injury (p<0.05). CONCLUSION: There was a significant GSH depletion and GSSG formation after cold storage and reperfusion due to a similar oxidative stress in optimal and suboptimal grafts, but these levels were not related to graft viability.

OBJETIVO: Comparar os efeitos após 6 horas do tratamento do choque hemorrágico (CH) com solução de NaCl 7,5% (Solução Salina Hipertônica - SSH) e Ringer Lactato (RL) sobre a função e integridade hepática em ratos. MÉTODOS: Ratos Wistar (n=16) machos foram submetidos a choque hemorrágico controlado (Pressão Arterial Média - PAM = 45 mmHg) durante 60 minutos e após ressuscitados com SSH (10% da perda volêmica, n=8) ou RL (4 vezes o volume sangüíneo retirado, n=8). Após 6 horas a função hepática foi determinada pela quantificação do fluxo biliar. A integridade hepática foi avaliada pelas bilirrubinas e pela alanino aminotransferase (ALT). RESULTADOS: Não foi constatada diferença de PAM entre os grupos durante os experimentos. O fluxo biliar apresentou recuperação significativa no grupo SSH em comparação ao grupo RL (p<0,05). O grupo SSH apresentou diminuição significativa nos níveis de ALT (p<0,001) e das bilirrubinas (p<0,001). CONCLUSÃO: Após 6 horas de tratamento do choque hemorrágico a SSH mostrou-se superior ao RL, recuperando a função e a integridade hepatocelular, provavelmente por melhora da perfusão nutricional hepática, e diretamente relacionada ao seu mecanismo de ação.

PEURPOSE: The comparison after 6h of hemorrhagic shock (HS) treatment with NaCl 7.5% (Hypertonic Saline Solution - SSH) or Ringer Lactate (RL) on liver function and integrity. METHODS: Male Wistar rats were submitted to HS (Mean Arterial Pressure - MAP= 45 mmHg) during 60 min and then treated with NaCl 7.5% (SSH, 10% of blood loss, n=8) or Ringer Lactate (RL, 400% of blood loss, n=8). After 6h rats were anesthetized, hepatic function was assessed by bile flow measurement and liver integrity evaluated by determination of alanine aminotransferase (ALT) and bilirubin activities. RESULTS: There was no difference in MAP between the groups during the whole experiments. Biliary flow showed a significant recovery after SSH treatment (p<0.05), and significant decrease of ALT (p<0.001) and bilirubin levels (p<0.001) in comparison to RL. CONCLUSION: Resuscitation of HS with NaCl 7.5% promoted better recovery of liver function and lesser hepatocellular damage after 6h of treatment compared to RL. The improvement is very likely related to increased microvascular perfusion provided by small volume resuscitation.

OBJETIVO: A apendicite aguda é a doença cirúrgica não-obstétrica mais comum da gravidez e pode ocorrer em qualquer idade gestacional. O seu diagnóstico freqüentemente é tardio, o que pode acarretar alto índice de perfuração e complicações. O presente estudo visa apresentar os resultados da videolaparoscopia no tratamento da apendicite aguda na gravidez. MÉTODO: São analisados retrospectivamente quatro casos de pacientes com suspeita de apendicite aguda avaliadas em serviço de cirurgia de urgência e submetidas à cirurgia videolaparoscópica no segundo trimestre da gestação. RESULTADOS: A videolaparoscopia confirmou o diagnóstico de apendicite aguda em três casos e o outro tratava-se de cisto ovariano roto. Todas foram tratadas pelo método laparoscópico, sem necessidade de conversão, e receberam alta hospitalar em cerca de 72 horas. Não houve complicações pós-operatórias. As pacientes foram acompanhadas no restante da gestação, e os partos ocorreram na data prevista, sem complicações maternas ou para os recém-nascidos. CONCLUSÃO: A apendicectomia laparoscópica na gravidez revelou-se um procedimento seguro, que possibilita uma recuperação pós-operatória mais rápida e sem evidências de que interfira com o curso da gestação. Entretanto, estudos com maior número de casos são necessários para estabelecer o seu real valor.

BACKGROUND: Acute appendicitis is the main abdominal non-obstetric surgical pathology during pregnancy. It may occur at any maternal age and in any gestational period. It is frequently diagnosed lately, leading to a high index of perforation and complications. The aim of the study was to evaluate the feasibility of videolaparoscopic appendectomy. METHOD: Four pregnant patients, all in the second trimester, who were attended at the Emergency Unit at Hospital Mãe de Deus with clinical suspicion of acute appendicitis, were submitted to videolaparoscopic exploration and were retrospectively evaluated. RESULTS: Laparoscopy confirmed acute appendicitis in 3 cases and the other was a ruptured hemorrhagic ovarian cyst. All patients were treated laparoscopicaly, and no conversion was needed. There were no post-operative complications and all four were discharged within 48 hours. The patients were followed and the deliveries were carried out in a proper form, without maternal or newborn complications. CONCLUSIONS: In this study, laparoscopic appendectomy was a safe procedure. It allowed a fast recovery and there were no apparent interference with gestacional course. However more studies with a great number of cases are necessary, in order to establish its real value.