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PURPOSE: To evaluate, in dogs, the biliary sphincter subjected to dilation by hydrostatic balloon by the point of view of structural alterations of the papilla and the biochemestry and bacterial contamination of the bile. METHODS: Twenty dogs were submitted to laparotomy, duodenotomy, and enlargement of the major duodenal papilla- GA(n=10) - with balloon of 8mm inflated with pressure of 0,5atm, during 2 minutes or to the sham procedure - GB(n=10). Blood samples collected on times t(0day), t(7days) and t(28days) were subjected to dosages of alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) for cholestasis evaluation. The collected material from the gall bladder at the same times were registered and numbered to be submitted to culture in BHI, blood agar (rich, non-selective element) and Mac Conkey (selective element for Gram-negative bacillus. On the 28th day three fragments of the papilla were tranversally cut by the choledoc axis 3mm from the duodenal papilla and the cuts, stained with hematoxylin-eosin and Masson's tricome, were evaluated according to their inflammatory reaction. RESULTS: The GGT and ALP averages on the three periods in the groups A and B did not show significant differences, not being characterizes the cholestasis. The bacterian contamination was significantly higher in GA (2,19) than in GB (1,96); the contamination was lower in the initial time compared with 7 and 28 days (t0

PURPOSE: Verify the role of ischemic preconditioning (IPC) in ischemia and reperfusion injury on gracilis muscle of rats. METHODS: Wistar rats (n=30) were distributed in three groups, I/R and IPC groups were subdivided concerning ischemia time. A near-amputation model of the posterior limb was produced by a hip joint level incision, preserving the vascular bundle and the femur bone and ischemia was induced for 2h and 4h, G-I 2h/R (n=6) and G-I 4h/R (n=6), followed by 1h of vascular reperfusion. The preconditioned groups, G-PCI 2h (n=6) and G-PCI 4h (n=6), were preceded by 3 cycles of 5min of ischemia followed by 5min of vascular reperfusion before sustained ischemia. In the Control Group, C-G (n=6) animals were subjected to regional approach. The analysis was done with Light Microscopy (LM). RESULTS: The levels of fibril fragmentation were progressive in the G-I 2h/R (67% of muscle preservation) and in the G-I4 h/R (0% of muscle preservation). However in the group of the precondition the lesion degree being in level similar to the group controls in the G-I 2h/R (100% of muscle preservation) while at G-I 4h/r occur less protection (67% of muscle preservation). The degree of tissue inflammatory reaction was worst at G-I 4h/R (0% without inflammation signals) than at G-I 2h/R (50% without inflammation signals); while in the precondition group G-IPC-2h (83% without inflammation signals) was better than the G-IPC-4h (67% without inflammation signals). The vascular stasis was absent only in 17% of the G-I 4h/R and in 33% of the G-I 2h/R. In precondition group, however, the vascular stasis was absent in 33% at G-IPC 2h and absent in 50% at G-IPC 4h. CONCLUSION: The IPC showed, in an earlier phase, a benefic role at I/R derived injury on gracilis muscle of rats, as proven for the largest preservation of the fibers muscular, smaller inflammatory reaction and smaller vascular stasis.

OBJETIVO: Delinear os parâmetros que norteiam a escolha de um modelo animal de doença e verificar na literatura biomédica recente quais as espécies animais de uso mais freqüente. MÉTODOS: Considerando a revisão da literatura são discutidos, os conceitos e as características de um modelo animal de doença. Destaca-se o consenso atual sobre quando usar um modelo animal, quais os critérios de sua escolha e os requisitos para um modelo adequado. Descreve quais os tipos de modelos animal de doença e discute as controvérsias da similaridade filogenética e os riscos inerentes a extrapolação dos modelos para os seres humanos. Baseado em uma pesquisa documental na base de dados da BIREME (Medline, Lilacs, Scielo e Biblioteca Cochrane) investiga quais os animais de experimentação mais citados nos artigos destas bases de dados. RESULTADOS: Verificou-se que o rato e o camundongo são os animais mais freqüentemente utilizados. O coelho, cão e o suíno seguem a lista nas referências de língua inglesa. Nas bases de dados da literatura Latino-americana o cão supera o número de citações de coelhos e suínos. Os primatas são minoria nas citações em todas as bases de dados. As revisões sistemáticas também têm no rato o maior número de citações, as demais espécies são citadas em igualdade de condições. CONCLUSÕES: O animal de experimentação é usado virtualmente em todos os campos da pesquisa biológica nos dias de hoje. A relação entre os humanos e os animais de outras espécies ganhou, através dos tempos, contornos mais definidos, a exploração de outras espécies tem regras e uma ética estabelecida, a indução dos resultados do animal para a espécie humana tem critérios claros e objetivos a serem preenchidos. O uso dos modelos experimentais, ou dos modelos animal de doença, ou dos animais de laboratório na pesquisa biomédica permite e deverão permitir nos próximos anos discussões epistemológicas, políticas, sociais, econômicas e religiosas.

OBJETIVO: estabelecer comparação entre as propriedades mecânicas das tenorrafias realizadas com poliamida (náilon) e polidioxanona (PDS). MÉTODOS: Foram utilizados 56 coelhos adultos, machos, Nova Zelândia, distribuídos em dois grupos e quatro subgrupos: GIA - tenorrafias com polidioxanona e avaliação após duas semanas; GIB - tenorrafias com polidioxanona e avaliação após quatro semanas; GIIA - tenorrafias com náilon e avaliação após duas semanas; GIIB - tenorrafias com náilon e avaliação após quatro semanas. Foram realizados ensaios de tração nas tenorrafias dos tendões dos coelhos. RESULTADOS: na avaliação aos quinze dias de pós-operatório, o náilon apresentou como resultados dos ensaios mecânicos, valores superiores que os do PDS para carga máxima, coeficiente de rigidez, deformação, deformação no limite de proporcionalidade, carga no limite de proporcionalidade, que foram as variáveis analisadas. CONCLUSÃO: aos trinta dias de pós-operatório não houve diferença significante entre o uso do náilon e o PDS.

A reinervação dos nervos periféricos pode ser realizada através de anastomoses término - terminais ou término-laterais, e este fenômeno tem sido amplamente estud ado. As anastomoses nervosas término-laterais tem sido utilizadas com pouca freqüência em relação as anastomoses término-terminais e contestada por alguns autores quanto a possibilidade de reinervação, quando a integridade do epineuro é mantida. Devido a estas divergências, estudou-se o efeito do epineuro na reinervação em anastomoses término-laterais, em ratos. Foram utilizados 20 ratos Wistar, adultos, distribuídos em dois grupos (A e B). No grupo A, 10 animais foram submetidos à secção do nervo fibular no membro pélvico direito e fixação desde à musculatura; no membro pélvico esquerdo foi realizada a secção do nervo fibular e anastomasado término-lateral com o nervo tibial. No grupo B, os procedimentos foram idênticos aos realizados no grupo A, sendo somente invertido os membros pélvicos. No nonagésimo dia do ato operatório, foi realizada uma biópsia em cada nervo fibular para análise histológica à microscópia óptica, onde a reinervação foi objeto de estudo. A reinervação ocorreu mostrando que a integridade do epineuro não impediu a regeneração axonal.

Várias substâncias identificáveis estão implicadas no processo de crescimento hepático, entre elas os fatores de crescimento. A maioria deles possui diferentes ações, estimulando a proliferação de células, ou mesmo inibindo na dependência de suas concentrações. Dentre os fatores de crescimento, ou somatomedinas, com ação sobre o fígado pode-se destacar: HGF; EGF; TGF-alpha; TGF b ; Interleucina 6; IGF; FGF; VEGF; KGF; HSS e ALR. A ação conjunta dos hormônios HGF, TGF-alpha, IL-6, TNF-alpha, norepinefrina, EGF, permite que insulina, glucagon e o próprio EGF manifestem seus efeitos. O HGF tem papel vital, talvez o principal "gatilho" deste processo, gerando um sinal endócrino que ativa fortemente a mitogênese nos hepatócitos já "preparados" pelo EGF, IL-6, insulina, matriz remanescente e outros, levando à síntese de DNA. Admite-se que o EGF também participe dos eventos iniciais do processo logo após a hepatectomia e que FGF, VEGF e KGF também participem dos eventos ligados à recomposição de outros tecidos.

OBJETIVO: Comparar a sutura simples contínua e a sutura contínua em oito vertical no fechamento da parede abdominal de ratos. MÉTODOS: Quarenta e oito ratos machos Wistar, foram submetidos a laparotomia padronizada e fechamento da parede abdominal com sutura simples contínua (n=24) e sutura contínua em oito-vertical (n=24), com fio de polipropileno. No 7° e 14° pós-operatório foram submetidos a eutanásia 12 animais de cada grupo e deles retirados a camada músculo-aponevrótica da parede abdominal envolvendo a cicatriz operatória e preparados para exames histológico e imunohistoquímico. Os segmentos levados ao exame histológico foram corados por Hematoxilina-eosina sendo feita observação qualitativa do processo cicatricial e Picrosirius red F3BA, para avaliação quantitativa do colágeno. Também foram estudadas as porcentagens de macrófagos na linha de sutura por imunohistoquímica. Para a quantificação de macrófagos e fibras colágenas foi utilizado avaliação histológica por digitalização de imagem, baseados nos princípios de espectrofotometria. Os dados encontrados foram analisados estatisticamente pelos testes qui-quadrado, exato de Fisher e Mann-Whitney (p< 0,05). RESULTADOS: A análise qualitativa, nos parâmetros necrose, fibrose, neovascularização, presença de abscesso, reação de corpo estranho e coaptação das bordas de sutura, não mostrou dados significantes nos dois grupos aos 7 ou 14 dias. A porcentagem de fibras colágenas foi significantemente maior, apenas no 7° dia, na sutura contínua em oito-vertical. A porcentagem de macrófagos mostrou-se significantemente maior na sutura simples contínua no 7º. dia. CONCLUSÃO : No 7° dia de pós-operatório a parede abdominal suturada em oito vertical apresenta significantemente, maior quantidade de fibras colágenas e menor quantidade de macrófagos do que a suturada por técnica contínua. Aos 14 dias de observação as suturas mostraram-se morfologicamente semelhantes.

Background: The differential diagnosis of the causal factors of acute pancreatitis is fundamental for its clinical follow-up, becoming relevant to establishing laboratory criteria that elucidate the difference between biliary and nonbiliary causes., Aim: The aim of this study was to establish criteria based on laboratory tests for the differential diagnosis between acute pancreatitis of biliary and nonbiliary causes and to identify laboratory tests with sufficient sensitivity to propose the creation of an algorithm for differential diagnosis between the causes., Methods: The research consisted of observational analysis, with a cross-sectional design of laboratory tests of two groups of patients with acute pancreatitis: group A: nonbiliary cause and group B: biliary cause. Hematocrit, white blood cell count, lactate dehydrogenase, glucose, lipase, amylase, total bilirubin, oxalacetic transaminase, pyruvic transaminase, gamma-glutamyltransferase, and alkaline phosphatase were investigated. Data were submitted to nonparametric tests and receiver operating characteristics., Results: Hematocrit values, number of leukocytes, lactate dehydrogenase, and glucose showed no significant difference between the groups (p>0.1). Lipase, amylase, total bilirubin, oxalacetic transaminase, pyruvic transaminase, gamma-glutamyltransferase, and alkaline phosphatase values showed a significant difference between groups (p<0.05). The oxalacetic transaminase, pyruvic transaminase, and alkaline phosphatase tests were most sensitive in determining the biliary cause, allowing the establishment of a cutoff point by the receiver operating characteristic test: pyruvic transaminase: 123.0 U/L (sensitivity: 69.2%; specificity: 81.5%), oxalacetic transaminase: 123.5 U/L (sensitivity: 57.3%; specificity: 78.8%), and alkaline phosphatase: 126.5 U/L (sensitivity: 66.1%; specificity: 69.4%), from which the probability of a correct answer increases., Conclusion: It was possible to establish criteria based on laboratory tests for the differential diagnosis between acute pancreatitis of biliary and nonbiliary origin; however, the tests did not show enough sensitivity to propose the creation of an algorithm for differential diagnosis between the same causes.

Purpose: To evaluate the effect of hyperbaric oxygenation (HBO) on angiogenesis in random rat skin flaps, by immunoexpression of vascular endothelial growth factor A (VEGF-A)., Methods: Forty adult rats were divided into four groups: GE) epilated; GE/HBO) epilated subjected to HBO; GER) epilated submitted to dorsal skin flap; GER/HBO) epilated subjected to dorsal skin flap + HBO. HBO was performed with rats inside a chamber under atmosphere close to 100% oxygen and pressure of 2.4 absolute atmospheres, 2h per day during seven consecutive days. GE and GER groups were placed in the hyperbaric chamber without HBO. Then, under anesthesia, skin flaps were removed and separated into three portions relative to pedicle fixation. The samples were fixed in formalin and processed for paraffin embedding. Histological sections were submitted to immunohistochemistry for VEGF-A detection. The number of immunostained-blood vessels were counted under light microscopy., Results: GE and GE/HBO groups showed normal and similar skin morphology in the three flap portions. A fibrin-leukocyte crust, along with denatured collagen and intense leukocyte infiltrate, was mainly observed in the dermis of the medial and distal flap portions of GER group. Meanwhile, the GER/HBO group presented more regions with intact collagen and small areas of leukocyte infiltrate in the three flap regions. VEGF-A-immunostained blood vessels were largely seen in all regions of GE and GE/HBO groups, whereas no significant differences were found between these groups. A decrease in vascularization was noticed in GER and GER/HBO groups, which was more evident in the most distal portion of the flaps. However, the number of VEGF-A-immunostained blood vessels in GER/HBO group was significantly higher when compared to GER group., Conclusions: Hyperbaric oxygenation was associated with increased angiogenesis and improved viability of rat skin flaps.

Background: The use of unfractionated heparin in hypovolemic shock, aortic clamping, and visceral reperfusion is still not established, despite evidence of inhibition of early cell damage. This study investigated the potential protective effect of unfractionated heparin on hepatic and renal apoptosis in a porcine ischemia and reperfusion model., Methods: Twenty-one male swine (Sus scrofa) were divided into 3 groups: sham (n = 5), heparin (n = 8), and nonheparin (n = 8). The heparin and nonheparin groups underwent hypovolemic shock for 30 min, supraceliac aortic clamping for 1 h and reperfusion for 3 h. Unfractionated heparin 200 mg/kg was administered to the heparin group during aortic clamping. Hemodynamic and laboratory parameters were monitored, including aminotransferase and serum urea. Histological lesion scores were applied to hematoxylin and eosin-stained liver and kidney sections. Apoptosis quantification was performed by caspase-3 immunohistochemistry., Results: The proposed model caused a severe cardiocirculatory disturbance in the heparin and nonheparin groups, observed by the carotid-femoral pressure gradient and lactic acidosis. There was no significant difference in hemodynamic and laboratory parameters between these two groups. The mean values of liver and renal histological lesion scores did not present any significant differences. Caspase-3 immunoexpression was lower in the heparin than the nonheparin group for both liver and kidney., Conclusions: Attenuation of liver and kidney cell apoptosis in pigs undergoing systemic heparinization suggests a potential use for heparin in modulating cell death under critical hemodynamic conditions., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: To analyze the effects of ischemic preconditioning (IPC) in the expression of apoptosis-related genes in rat small intestine subjected to ischemia and reperfusion., Methods: Thirty anesthetized rats underwent laparotomy and were drive into five groups: control (CG); ischemia (IG); ischemia and reperfusion (IRG); IPC and ischemia (IG+IPC); IPC and ischemia and reperfusion (I/RG+IPC). Intestinal ischemia was performed by clamping the superior mesenteric artery for 60 minutes, whereas reperfusion lasted for 120 minutes. IPC was carried out by one cycle of 5 minutes of ischemia followed by 10 minutes of reperfusion prior to the prolonged 60-minutes-ischemia and 120-minutes-reperfusion. Thereafter, the rats were euthanized and samples of small intestine were processed for histology and gene expression., Results: Histology of myenteric plexus showed a higher presence of neurons presenting pyknotic nuclei and condensed chromatin in the IG and IRG. IG+IPC and I/RG+IPC groups exhibited neurons with preserved volume and nuclei, along with significant up-regulation of the anti-apoptotic protein Bcl2l1 and down-regulation of pro-apoptotic genes. Moreover, Bax/Bcl2 ratio was lower in the groups subjected to IPC, indicating a protective effect of IPC against apoptosis., Conclusion: Ischemic preconditioning protect rat small intestine against ischemia/reperfusion injury, reducing morphologic lesions and apoptosis.

Purpose: To investigate the role of atenolol in the gene expression of caspase 1 (Casp1) and Bcl2L1 on vascular endothelium of rat intestine after ischemia and reperfusion (IR)., Methods: Eighteen adult male Wistar rats were randomly divided into 3 groups (n=6): SG (Sham group): no clamping of the superior mesenteric artery; IRG: IR plus saline group: IRG+At: IR plus Atenolol group. Rats from IRG and IRG+At were subjected to 60 min of intestinal ischemia and 120 min of reperfusion. Atenolol (2mg/kg) or saline were injected in the femoral vein 5 min before ischemia, 5 min and 55 min after reperfusion. Thereafter, intestinal segments were appropriately removed and processed for Endothelial Cell Biology Rat RT2 Profiler PCR Array., Results: the anti-apoptotic Bcl2L1 gene expression was significantly down-regulated (-1.10) in the IRG and significantly up-regulated in the IRG+At (+14.15). Meanwhile, despite Casp1 gene expression was upregulated in both groups, it was significantly higher in the IRG (+35.06) than the IRG+At (+6.68)., Conclusions: Atenolol presents antiapoptotic effects on rat intestine subjected to IR partly by the up-regulation of the anti-apoptotic Bcl2L1 gene expression. Moreover, atenolol can mitigate the pro-apoptotic and pro-inflammatory effects of Casp1 gene on rat intestine after IR.

Purpose: To investigate the gene expression related to inflammation on mice subjected to intestinal ischemia and reperfusion (I/R) and treated with ischemic preconditioning (IPC)., Methods: Thirty rats (EPM-Wistar), distributed in five groups of six animals each, were underwent anesthesia and laparotomy. The ischemia time was standardized in 60 minutes and the reperfusion time 120 minutes. IPC was standardized in 5 minutes of ischemia followed by 10 minutes of reperfusion accomplished before I/R. The control group was submitted only to anesthesia and laparotomy. The other groups were submitted to ischemia, I/R, ischemia + IPC and I/R + IPC. It was collected a small intestine sample to analyses by Quantitative Polymerase Chain Reaction in real Time (RT-qPCR) and histological analyses. It was studied 27 genes., Results: The groups that received IPC presented downregulation of genes, observed in of genes in IPC+ischemia group and IPC+I/R group. Data analysis by clusters showed upregulation in I/R group, however in IPC groups occurred downregulation of genes related to inflammation., Conclusion: The ischemia/reperfusion promoted upregulation of genes related to inflammation, while ischemic preconditioning promoted downregulation of these genes.

Purpose: To determine whether the absence of transglutaminase 2 enzyme (TG2) in TG2 knockout mice (TG2-/-) protect them against early age-related functional and histological arterial changes., Methods: Pulse wave velocity (PWV) was measured using non-invasive Doppler and mean arterial pressure (MAP) was measured in awake mice using tail-cuff system. Thoracic aortas were excised for evaluation of endothelial dependent vasodilation (EDV) by wire myography, as well as histological analyses., Results: PWV and MAP were similar in TG2-/-mice to age-matched wild type (WT) control mice. Old WT mice exhibited a markedly attenuated EDV as compared to young WT animals. The TG2-/-young and old mice had enhanced EDV responses (p<0.01) as compared to WT mice. There was a significant increase in TG2 crosslinks by IHC in WT old group compared to Young, with no stain in the TG2-/-animals. Optical microscopy examination of Old WT mice aorta showed thinning and fragmentation of elastic laminae. Young WT mice, old and young TG2-/-mice presented regularly arranged and parallel elastic laminae of the tunica media., Conclusion: The genetic suppression of TG2 delays the age-induced endothelial dysfunction and histological modifications.

Purpose: To investigate the role of the exogenous supply of adenosine triphosphate (ATP) in the expression of Bax and Bcl2L1 genes in intestinal ischemia and reperfusion (IR) in rats., Methods: The study was designed as a randomized controlled trial with a blinded assessment of the outcome. Eighteen adult male Wistar-EPM1 rats were housed under controlled temperature and light conditions (22-23°C, 12 h light/dark cycle). The animals were randomly divided into 3 groups: 1. Sham group (SG): no clamping of the superior mesenteric artery; 2. Ischemia and reperfusion group (IRG): 3. Ischemia and reperfusion plus ATP (IRG + ATP). ATP was injected in the femoral vein before and after ischemia. Afterwards, intestinal segments were appropriately removed and processed for Endothelial Cell Biology Rat RT2 Profiler PCR Array., Results: ATP promoted the upregulation of Bcl2L1 gene expression, whereas it did not have significant effects on Bax gene expression. In addition, the relation of Bax/Bcl2L1 gene expression in the IRG group was 1.39, whereas it was 0.43 in the IRG + ATP group. Bcl2L1 plays a crucial role in protecting against intestinal apoptosis after ischemia and reperfusion. Increased Bcl2L1 expression can inhibit apoptosis while decreased Bcl2L1 expression can trigger apoptosis., Conclusion: Adenosine triphosphate was associated with antiapoptotic effects on the rat intestine ischemia and reperfusion by upregulating of Bcl2L1 gene expression.

Purpose: To evaluate the effect of hyperbaric oxygenation (HBO) on the expression of the genes antioxidant glutathione peroxidase 4 (Gpx4) and lactoperoxidase (Lpo) in the lung of mice subjected to intestinal ischemia and reperfusion (IIR)., Methods: Control group (CG) in which were subjected to anesthesia, laparotomy and observation for 120 minutes; an ischemia and reperfusion group (IRG) subjected to anesthesia, laparotomy, small bowel ischemia for 60 minutes and reperfusion for 60 minutes; and three groups treated with HBO during ischemia (HBOG + I), during reperfusion (HBOG + R) and during ischemia and reperfusion (HBOG + IR). Studied 84 genes of oxidative stress by the method (RT-qPCR). Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student's t-test p<0.05)., Results: Gpx4 and Lpo were hiperexpressed on IRG, showing a correlation with these genes with lung oxidative stress. Treated with HBO, there was a significant reduction on genic expression on HBOG+I., Conclusion: Hyperbaric oxygenation showed to be associated with decreased expression of these antioxidant genes, suggesting a beneficial effect on the mechanism of pulmonary oxidative stress whenever applied during the ischemia.

Purpose: To investigate the expression of nitric oxide synthase (NOS) and apoptosis associated with ischemic preconditioning (IPC) and pentoxifylline (PTX) in intestinal ischemia (I) and reperfusion (R) injury., Methods: Thirty male rats were assigned to 5 groups: (CG), no clamping of the superior mesenteric artery (90 minutes); (IR-SS) saline + ischemia (30 minutes) + reperfusion (60 minutes); (IR-PTX) PTX + ischemia (30 minutes) + reperfusion (60 minutes); (IPC-IR-SS) 5 minutes of ischemia + 5 minutes of reperfusion (IPC) + saline + I(30 minutes)+R(60 minutes); and (IPC-IR-PTX) IPC + PTX + I(30 minutes)+ R(60 minutes)., Results: The application of IPC and PTX showed a significantly lower immunohistochemistry reaction for active caspase-3 (P<0.05) compared to IR+SS. The number of cells immunoreactive to BCL-2 was higher in the IR-PTX group (P>0.05). The NOS-2 expression (qRTPCR) in the IR-PTX group (P<0.05) was higher than the values for the IPC+IR-SS and IPC-IR-PTX groups. The NOS-3 expression was significantly upper in the IPC-IR-PTX group than in the CG (P<0.05), the IR-SS (P<0.05) and the IR-PTX (P<0.05) groups., Conclusions: The BCL-2 and active caspase-3 showed beneficial effects on PTX and IPC. The expression of NOS-2 and NOS-3 in the IPC and IPC-PTX groups showed no synergistic effect.

Purpose: To investigate the effects of hyperbaric oxygenation (HBO) on intestinal ischemia and reperfusion (IR) injury, we evaluated the expression of 84 genes related to oxidative stress and the antioxidant response in mouse hearts., Methods: Four groups were subjected to 60 minutes of intestinal ischemia followed by 60 minutes of reperfusion: IRG, ischemia and reperfusion group without HBO; HBO-IG, which received HBO during ischemia; HBO-RG, which received HBO during reperfusion; and HBO-IRG, which received HBO during ischemia and reperfusion. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes. The (RT-qPCR) method was applied. Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student's t-test p<0.05)., Results: Eight genes (9.52%) were hyperexpressed in the IRG. When the HBO groups were compared to the IRG, we found a decrease in the expression of eight genes in the HBO-IG, five genes in the HBO-RG, and seven genes in the HBO-IRG., Conclusion: The reduction in the expression of genes related to oxidative stress and antioxidant defense following HBO in mouse hearts resulting from intestinal IR injury was more favorable during the ischemic period than during the reperfusion period.

Purpose:: To investigate the role of ischemic preconditioning (IPC) and pentoxifylline (PTX) in intestinal mucosa ischemia/reperfusion injury (IR)., Methods:: Thirty rats were assigned to 5 groups (N=6): (CG): no clamping of the superior mesenteric artery (90 min.); (IR-SS): saline + ischemia (30 min.) + reperfusion (60 min.); (IR-PTX): PTX + ischemia (30min.) + reperfusion (60 min.); (IPC-IR-SS): 5 min. of ischemia + 5 minutes of reperfusion (IPC) + saline + ischemia (30 min.) + reperfusion (60 min.); (IPC-IR-PTX ): 5 min. of ischemia + 5 min. of reperfusion (IPC) + PTX + 30 min. of I + 60 minutes of R., Results:: The IR-PTX, IPC-IR-SS and IPC-IR-PTX groups had significantly lower scores of mucosa damage than the IR-SS group. IR-PTX group showed higher scores than the IPC-IR-PTX group, in accordance with the hypothesis of a favorable effect of IPC alone or in association with PTX. Additionally, IPC-IR-SS had a higher damage score than the IPC-IR-PTX. The villi height and crypt depth were similar in all groups. The villi height in the IR-SS was significantly lower., Conclusion:: Ischemic preconditioning or pentoxifylline alone protect the intestinal mucosa from ischemia/reperfusion injury. However, they do not have a synergistic effect when applied together.

Background: The goal of this study was to investigate whether exogenous offer of L-arginine (LARG) modulates the gene expression of intestinal dysfunction caused by ischemia and reperfusion., Methods: Eighteen Wistar-EPM1 male rats (250-300 g) were anesthetized and subjected to laparotomy. The superior mesenteric vessels were exposed, and the rats were randomized into 3 groups (n = 6): the control group (CG), with no superior mesenteric artery interruption; the ischemia/reperfusion group (IRG), with 60 minutes of ischemia and 120 minutes of reperfusion and saline injections; and the L-arginine group (IRG + LARG), with L-arginine injected in the femoral vein 5 minutes before ischemia, 5 minutes after reperfusion, and after 55 minutes of reperfusion. The total RNA was extracted and purified from samples of the small intestine. The concentration of each total RNA sample was determined by using spectrophotometry. The first-strand complementary DNA (cDNA) was synthesized in equal amounts of cDNA and the Master Mix SYBR Green qPCR Mastermix (SABiosciences, a Qiagen Company, Frederick, Md). Amounts of cDNA and Master Mix SYBR Green qPCR Mastermix were distributed to each well of the polymerase chain reaction microarray plate containing the predispensed gene-specific primer sets for Bax and Bcl2. Each sample was evaluated in triplicate, and the Student t test was applied to validate the homogeneity of each gene expression reaction (P < .05)., Results: The gene expression of Bax in IRG (+1.48) was significantly higher than in IRG-LARG (+9.69); the expression of Bcl2L1 in IRG (+1.01) was significantly higher than IRG-LARG (+22.89)., Conclusions: The apoptotic cell pathway of 2 protagonists showed that LARG improves the gene expression of anti-apoptotic Bcl2l1 (Bcl2-like 1) more than the pro-apoptotic Bax (Bcl2-associated X protein)., (Copyright © 2016. Published by Elsevier Inc.)

Background: This study evaluated the morphology of the rat liver when hyperbaric oxygen (HBO) was used at various stages of ischemia and reperfusion., Methods: Thirty-two male Wistar rats, subjected to 30 minutes of hepatic ischemia and 30 minutes of reperfusion, were randomly assigned as follows: GIR (n = 8), control without HBO; GHBO/I (n = 8), in which HBO was applied only during ischemia; GHBO/R (n = 8), HBO only during reperfusion; and GHBO/IR (n = 8), HBO during both ischemia and reperfusion. Feasibility scores of hepatocytes were determined by assessing 8 items related to liver injury., Results: The histologic injury score of the hepatic specimens was significantly lower in the GHBO/I group (79.0 ± 0.1) compared with the GIR group (135.0 ± 0.1). HBO was not effective when applied during reperfusion (GHBO/R, 151.3 ± 0.1) or during the ischemia plus reperfusion period (GHBO/IR, 131.0 ± 0.1). The sum was significantly higher (P < .05) in HBO-treated animals during the reperfusion period (ie, in the GHBO/R group compared with any of the other groups)., Conclusions: A favorable effect was obtained when HBO was administered early during ischemia. HBO given in later periods of reperfusion was associated with a more severe sum index percentage of liver damage., (Copyright © 2016. Published by Elsevier Inc.)

Objective: To evaluate the ability of fibrin adhesive in promoting the meniscus fixation within two, four and eight weeks compared to the conventional soft-tissue suture technique., Materials and Methods: 36 right medial menisci of rabbits preserved at negative 73° Celsius for 30 days were transplanted to animals of the same sample and fixed with soft-tissue suture or fibrin glue. After 2, 4 or 8 weeks, the appearance of the menisci and the quality of fixation were macroscopically checked and evaluated by a scoring system. The findings were subjected to the statistical study of variance analysis (p ≤ 0.05%)., Results: The deep-frozen meniscus preservation maintained the integrity of the meniscus transplant, and, macroscopically, there was no significant reduction of the length of the meniscus in all post-transplant periods (p = 0.015). The menisci fixed with fibrin showed slight changes in color and surface roughness. There were no signs of rejection or infection in both groups. Suture fixation scoring was superior (p = 0.015) in all periods (80% of total fixation) as compared to the setting promoted by fibrin (20% of total fixation)., Conclusion: The homologous transplantation of the meniscus of rabbits experienced various degrees of integration to the knee according to the fixation method; the surgical soft tissues suturing technique was shown to be superior in the evaluation of scores compared to the fixation with fibrin adhesive.

Objective: This study compares the results of an objective structured clinical examination (OSCE) between 2 groups of students before an internship and after 6 months of clinical practice in an internship., Methods: Seventy-two students participated, with 36 students in each cohort. The OSCEs were performed in the simulation laboratory before the participants' clinical practice internship and after 6 months of the internship. Students were tested in 9 stations for clinical skills and knowledge. The same procedures were repeated for both cohorts. The t test was used for unpaired parametric samples and Fisher's exact test was used for comparison of proportions., Results: There was no difference in the mean final score between the 2 groups (p = .34 for test 1; p = .08 for test 2). The performance of the students in group 1 was not significantly different when performed before and after 6 months of clinical practice, but in group 2 there was a significant decrease in the average score after 6 months of clinical practice., Conclusions: There was no difference in the cumulative average score for the 2 groups before and after 6 months of clinical practice in the internship. There were differences within the cohorts, however, with a significant decrease in the average score in group 2. Issues pertaining to test standardization and student motivation for test 2 may have influenced the scores.

Purpose: To evaluate the morphology, necrotic area and collagen content in skin flaps of rats subjected to hyperbaric oxygenation (HBO)., Methods: Forty adult rats were divided into four groups: GEC - epilated; GE/HBO - epilated subjected to HBO; GER - epilated submitted to skin flap (2 cm in width /8 cm length in the dorsal area) and GER/HBO - epilated, subjected to skin flap and HBO. HBO (2.4 ATA) was performed for two hours during seven consecutive days. In the eighth day, the rats were anesthetized and the skin flaps were removed and separated into three portions, relative to pedicle fixation. The material fixed in 10% formalin was processed for paraffin embedding; sections were stained by H.E and subjected to picrosirius-red method. The slides examined under light microscopy for evaluation of the collagen content in polarized light microscope and ImageLab(r) software (Bio-Rad)., Results: The data showed larger area of necrosis and lower levels of collagen in the three regions of the GER group, whereas in the GER/HBO group the collagen content was similar to the GEC and GE/HBO groups., Conclusion: Hyperbaric oxygenation reduced the area of necrosis and preserved the morphology and collagen content in skin flaps of rats.

Objectives: The effectiveness of noninvasive positive-pressure ventilation in preventing reintubation due to respiratory failure in children remains uncertain. A pilot study was designed to evaluate the frequency of extubation failure, develop a randomization approach, and analyze the feasibility of a powered randomized trial to compare noninvasive positive-pressure ventilation and standard oxygen therapy post extubation for preventing reintubation within 48 hours in children with respiratory failure., Design: Prospective pilot study., Setting: PICU at a university-affiliated hospital., Patients: Children aged between 28 days and 3 years undergoing invasive mechanical ventilation for greater than or equal to 48 hours with respiratory failure after programmed extubation., Interventions: Patients were prospectively enrolled and randomly assigned into noninvasive positive-pressure ventilation group and inhaled oxygen group after programmed extubation from May 2012 to May 2013., Measurements and Main Results: Length of stay in PICU and hospital, oxygenation index, blood gas before and after tracheal extubation, failure and reason for tracheal extubation, complications, mechanical ventilation variables before tracheal extubation, arterial blood gas, and respiratory and heart rates before and 1 hour after tracheal extubation were analyzed. One hundred eight patients were included (noninvasive positive-pressure ventilation group, n = 55 and inhaled oxygen group, n = 53), with 66 exclusions. Groups did not significantly differ for gender, age, disease severity, Pediatric Risk of Mortality at admission, tracheal intubation, and mechanical ventilation indications. There was no statistically significant difference in reintubation rate (noninvasive positive-pressure ventilation group, 9.1%; inhaled oxygen group, 11.3%; p > 0.05) and length of stay (days) in PICU (noninvasive positive-pressure ventilation group, 3 [1-16]; inhaled oxygen group, 2 [1-25]; p > 0.05) or hospital (noninvasive positive-pressure ventilation group, 19 [7-141]; inhaled oxygen group, 17 [8-80])., Conclusions: The study indicates that a larger randomized trial comparing noninvasive positive-pressure ventilation and standard oxygen therapy in children with respiratory failure is feasible, providing a basis for a future trial in this setting. No differences were seen between groups. The number of excluded patients was high.

Purpose: The aim of this study was to evaluate the Eye Retinopathy Trainer® as a teaching tool for direct ophthalmoscopy examination by comparing it with the traditional method using volunteers., Methods: Fourth year medical students received training in direct ophthalmoscopy using a simulation tool and human volunteers. Ninety students were randomized into a Simulation Group or a Control Group by the inclusion or absence of the simulation model in classroom practice. Differences between the groups were analyzed using unpaired Student's t-test., Results: The Simulation Group was superior to the Control Group, with 51.06% successful in performing fundus examination in both the anatomical model simulation and the human model in comparison with 21.15% in the Control Group., Conclusion: The Eye Retinopathy Trainer® appears to be an effective teaching tool for practice and improvement of ophthalmologic examination among fourth year medical students.

Background: Facial aging is a natural biological process with symptoms such as sagging tissue, accentuated lines, furrows, wrinkles, dyschromias, and loss of facial volume. Rhytidectomy alone often fails to achieve a patient's expected goals, which is why there is a high demand for adjunct laser skin treatment., Methods: From January 2007 to February 2013, a total of 80 patients with skin types Fitzpatrick I-IV underwent large undermined cutaneous flap rhytidectomy and superficial muscular aponeurotic system (SMAS) plicature plus hyaluronic acid injection on the nasolabial folds and lips and concomitant Lumenis UltraPulse CO2 Active FX total ablation mode resurfacing of nonundermined skin. The undermined skin was treated with a fractional laser using different energies depending on the type of skin. Patients were evaluated at 5, 10, 15, 30, 60, and 90 days after the operation. At the last evaluation patients completed a specific questionnaire about satisfaction., Results: Complications included expansive hematomas (5 %), partial necrosis (1.25 %), bacterial infection (1.25 %), herpetic infection (1.25 %), hypertrophic scar (1.25 %), and spot hyperchromia (1.25 %). 95 % of patients were extremely satisfied, 3.75 % were satisfied, and only 1.25 % were unsatisfied., Conclusion: The combination of subcutaneous flap rhytidectomy and SMAS plicature with fractional laser resurfacing plus hyaluronic acid injection is a safe procedure with low incidence of major complications and improves patient satisfaction.

Objective: To evaluate the perioperative use of atenolol in reducing the incidence of hematoma after rhytidoplasty., Methods: Between January 2007 and February 2013, 80 patients were randomized into two groups: Group A (n = 26) received perioperative atenolol in order to maintain heart rate (PR) around 60 per minute; Group B (n = 54) did not receive atenolol. Both groups underwent the same anesthetic and surgical technique. We monitored blood pressure (BP), HR, hematoma formation and the need for drainage. Patients were followed-up until the 90th postoperative day. The variables were compared between the groups using the ANOVA test. Continuous variables were presented as mean ± standard deviation and the differences were compared with the Student's t test. Values of p d" 0.05 were considered significant., Results: In group A the mean BP (110-70 mm Hg ± 7.07) and HR (64 / min ± 5) were lower (p d" 0.05) than in group B (135-90 mm Hg ± 10.6) and (76 / min ± 7.5), respectively. There were four cases of expansive hematoma in group B, all requiring reoperation for drainage, and none in group A (p d" 0,001)., Conclusion: The perioperative use of atenolol caused a decrease in blood pressure and heart rate and decreased the incidence of expanding hematoma after rhytidectomy.

Purpose: To investigate if expression of genes encoding pro and anti-apoptotic proteins in the rat enteric endothelial cells stimulated by intestinal ischemia followed by reperfusion (IR) can be modified by treatment with heparin (HP)., Methods: Eighteen adult Wistar rats were divided in three groups: sham group submitted to laparotomy only (SG), ischemia followed by reperfusion group (IRG); ischemia followed by reperfusion plus pretreatment with HP 100 mg.kg-1 (IRG+HP). Ischemia was performed by clamping of the superior mesenteric artery. After 60 min of ischemia, metal clamps were removed for reperfusion for 120 min. Gene expression of encoding pro (Casp1, Casp6, Casp3, Cflar, Fas and Pgl) and anti-apoptotic (Bcl2, Bcl2l1 and Naip2) proteins in rat enteric endothelial cells was evaluated by PCR microarray method., Results: Compared to rat endothelial cells of SG, the expression of pro-apoptotic genes was up-regulated in IRG while anti-apoptotic genes were down-regulated. In contrast, the expression of anti-apoptotic genes in IRG+HP was up-regulated while pro-apoptotic genes was down-regulated compared to SG., Conclusion: The attenuation by heparin of intestinal ischemia-reperfusion previously demonstrated in rodents could be related with ability of this drug to stimulate and reduce gene expression of encoding anti and pro-apoptotic proteins, respectively.

Introduction:  Benign idiopathic tonsillar hypertrophy (HBI) may affect a child's quality of life and sleep. Several studies have sought to relate the clinical features of HBI with the infectious and/or immunologic changes that occur., Objective:  To increase the knowledge of the etiology of HBI., Data Synthesis:  From 2012 to 2013 we conducted a retrospective observational study of 101 children with HBI who underwent tonsillectomies at Ambulatory ENT General Hospital of the East Zone of São Paulo City, a region with a poor socioeconomic population. Preoperative serologic results were available to confirm mononucleosis, cytomegalovirus, anti-streptolysin O (ASLO) and immunoglobulins. The mean patient age was 5.8 years (55% male, 45% female). Using the Mann-Whitney U test, we identified significant gender differences in the parameters of immunoglobulins (Ig) M (IgM), IgA, and IgE. Forty-seven percent of the patients had increased ASLO levels, and 37% had increased IgE levels., Conclusion:  An evaluation of a patient's serologic parameters and laboratory results may be relevant to the etiology and prevention of HBI. Based on the results obtained from the study sample, the identification of etiologic agents and causative factors remain a public health challenge that affects the quality of life of children.

Purpose: To determine the gene expression profile associated with oxidative stress and antioxidant defense in the lung tissue of mice subjected to intestinal ischemia and reperfusion., Methods: Twelve male, inbred mice (C57BL/6) were randomly assigned to one of two groups. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes; the ischemia/reperfusion group (IRG) was subjected to anesthesia, laparotomy, and ischemia of the small intestine for 60 minutes and to 60 minutes of reperfusion. A pool of six mice from each group was subjected to a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to analyze the oxidative stress and antioxidant defense genes. All genes that were up-regulated or down-regulated greater than three-fold, based on the algorithm [2^(ΔΔCt)], were considered to be biologically meaningful., Results: Out of a total of 84 genes in the lung that are related to oxidative stress, 67 (79.7%) were up-regulated and 17 (20.2%) were down-regulated. Only two genes (2.3%), Lpo (lactoperoxidase) (+3.51) and Gpx4 (glutathione peroxidase) (+4.10), were expressed above the three-fold threshold, while none of the down-regulated genes were expressed outside of this threshold., Conclusion: The intestinal ischemia/reperfusion injury promoted a gene expression profile consisting of the positive expression of oxidative genes in a remote organ. This suggests that activate signaling pathways are implicated in both cell survival and the maintenance of genome integrity in the lung.

Background: Intestinal ischemia-reperfusion is a frequent clinical event associated to injury in distant organs, especially the heart., Objective: To investigate the gene expression of oxidative stress and antioxidant defense in the heart of inbred mice subjected to intestinal ischemia and reperfusion (IR)., Methods: Twelve mice (C57BL/6) were assigned to: IR Group (GIR) with 60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion; Control Group (CG) which underwent anesthesia and laparotomy without IR procedure and was observed for 120 minutes. Intestine and heart samples were processed using the RT-qPCR/Reverse transcriptase-quantitative Polymerase Chain Reaction method for the gene expression of 84 genes related to oxidative stress and oxidative defense (Student's "t" test, p<0.05)., Results: The intestinal tissue (GIR) was noted to have an up-regulation of 65 genes (74.71%) in comparison to normal tissue (CG), and 37 genes (44.04%) were hyper-expressed (greater than three times the threshold allowed by the algorithm). Regarding the remote effects of intestinal I/R in cardiac tissue an up-regulation of 28 genes (33.33%) was seen, but only eight genes (9.52%) were hyper-expressed three times above threshold. Four (7.14%) of these eight genes were expressed in both intestinal and cardiac tissues. Cardiomyocytes with smaller and pyknotic nuclei, rich in heterochromatin with rare nucleoli, indicating cardiac distress, were observed in the GIR., Conclusion: Intestinal I/R caused a statistically significant over expression of 8 genes associated with oxidative stress in remote myocardial tissue.

Purpose: To evaluate the effect of a local application of simvastatin gel in repairing bone defects in the femurs of rabbits., Methods: Two standard surgical cavities were created in the femoral epiphysis of 18 rabbits. In the simvastatin group (SG), the cavities were filled with a collagen sponge soaked in 0.5 ml of a simvastatin (1 mg) gel, and the cavities were covered with a biological membrane. The bone cavities in the second group (control group) were filled with a blood clot and covered with a biological membrane. On the 7th, 21st and 42nd days, six animals in each group were euthanized, and the femurs were subject to histological evaluation (vascularity, fibrosis, reactive bone formation, osteoblasts, and osteoclasts) and immunohistochemical (anti-VEGF and anti-osteocalcin) analysis. The results were analyzed using a Wilcoxon test (p<0.05)., Results: There were significant differences between the two groups: the SG had greater scores in comparison with the CG in terms of the degree of vascularity on the 7th and the 21st days, fibrosis on the 21st day, bone formation reaction on the 21st and the 42nd days and the number of osteoblasts and osteoclasts on the 42nd day. The immunohistochemical expression was also greater for osteocalcin and VEGF on the 7th, 21st and 42nd days., Conclusion: Surgical defects created in rabbit femurs were treated locally with simvastatin gel to stimulate bone repair, which promoted an ameliorative effect in the morphological and immunohistochemical markers of bone regeneration.

Purpose: To determine the gene expressions profile related to the oxidative stress and the antioxidant response in the kidneys of mice subjected to intestinal ischemia and reperfusion., Methods: Twelve inbred mice (C57BL/6) were randomly assigned to one of two groups: the control group (CG) underwent anesthesia and was observed for 120 min and the ischemia/reperfusion group (IRG), animals were anesthetized and subjected to laparotomy and ischemia for 60 minutes followed by 60 minutes of reperfusion. The expressions of 84 genes from the kidney were determined by the Reverse Transcription qualitative Polymerase Chain Reaction (RT-qPCR). All genes that were up regulated by more than threefold using the algorithm [2(ΔΔCt)] were considered statically significant (p<0.05)., Results: In the IRG group 29 (34.52%) of 84 genes, were up regulated by more than threefold. The genes that were differentially up regulated in the glutathione peroxidase cluster (10 genes): were Gpx2 and Gpx7. The genes that were up regulated in the peroxidase cluster (16 genes) were following: Duox1, Epx, Lpo, Mpo, Ptgs2, Rag2, Serpinb1b, Tmod1 and Tpo. The genes that up regulated in the reactive oxygen species cluster (16 genes): Il19, Il22, Nos2, Nox1, Noxa1, Noxo1, Recql4 and Sod2. The genes that were up regulated in the oxidative stress cluster (22 genes) were: Mpp4, Nudt15, Upc3 and Xpa. The genes that were up regulated in the oxygen carriers cluster (12 genes) were: Hbq1, Mb, Ngb, Slc38a1 and Xirp1. The peroxiredoxins genes (10) showed no consistent differential regulation., Conclusion: The genes related to oxidative stress and antioxidant defense showed increased expression in renal tissue trigged intestinal ischemia and reperfusion.

Unlabelled: Hyperbaric oxygen therapy (HBOT) has enhanced the prevention and treatment of auditory ailments such as ototoxicity., Objective: To study the effects of HBOT upon ototoxic injuries produced by amikacin., Method: This experimental study included 12 albino guinea pigs, whose auditory function was assessed through distortion product otoacoustic emissions (DPOAEs) and brainstem auditory evoked potentials (BAEPs) before and after the administration of amikacin (600 mg/kg/day) and HBOT sessions (2 ATA, 60 minutes). Morphological features were analyzed through scanning electron microscopy. Subjects were divided into four groups, as follows: group 1 - saline solution + HBOT; group 2 - amikacin for 8 days; group 3 - amikacin + seven days of rest; and group 4 - amikacin + HBOT., Results: Group 1 subjects had preserved function and morphology throughout the experiment; Group 2 subjects had statistically significant levels of hair cell injury and functional impairment; Subjects on groups 3 and 4 had statistically significant functional and morphological impairment after the administration of amikacin, which were still present after the proposed procedures had been carried out., Conclusion: Hyperbaric oxygen therapy did not change the cochlear hair cell morphology or the electro-physiological thresholds of the guinea pigs given amikacin.

Purpose: To investigate the effect of sildenafil citrate (SC) on skeletal muscle ischemia-reperfusion (IR) injury in rats., Methods: Adult male Wistar rats were randomized into three groups: vehicle-treated control (CTG), sildenafil citrate-treated (SCG), and sham group (SG). CTG and SCG had femoral artery occluded for 6 hours. Saline or 1 mg/kg of SC was given 5.5 hours after occlusion. SG had a similar procedure without artery occlusion. Soleus muscle samples were acquired 4 or 24h after the reperfusion. Immunohistochemistry caspase-3 analysis was used to estimate apoptosis using the apoptotic ratio (computed as positive/negative cells). Wilcoxon rank-sum or Kruskal-Wallis tests were used to assess differences among groups., Results: Eighteen animals were included in the 4h reperfusion groups and 21 animals in the 24h reperfusion groups. The mean apoptotic ratio was 0.18 ± 0.1 for the total cohort; 0.14 ± 0.06 for the 4h reperfusion groups and 0.19 ± 0.08 for the 24h groups (p<0.05). The SCG had lower caspase-3 ratio compared to the control groups at the 24h reperfusion time point (p<0.05)., Conclusion: Sildenafil citrate administration after the onset of the ischemic injury reduces IR-induced cellular damage in skeletal muscle in this rat hindlimb ischemia model.

Purpose: To investigate the effects of ischemic preconditioning (IPC) on the expression of pro and anti-apoptotic genes in rat endothelial cells undergoing enteric ischemia (I) and reperfusion (R)., Methods: Thirty rats underwent clamping of the superior mesenteric vessels. Sham group (GS) laparotomy only; Ischemia (GI): intestinal ischemia (60 min); Ischemia and Reperfusion (GIR): ischemia (60 min) and reperfusion (120 min); Ischemia and intestinal ischemic preconditioning (GI + IPC) : 5 minutes of ischemia followed by 10 min of reperfusion before sustained ischemia (60 min) ischemia and reperfusion and IPC (GIR + IPC): 5 min ischemia followed by 10 min of reperfusion before sustained ischemia (60min) and reperfusion (120 min). Rat Endothelial Cell Biology (PCR array) to determine the expression of genes related to endothelial cell biology., Results: Gene expression of pro-apoptotic markers (Casp1, Casp6, Cflar, Fas, and Pgl) was down regulated in GI+IPC and in GIR + IPC. In contrast, the expression of anti-apoptotic genes (Bcl2 and Naip2), was up-regulated in GI + IPC and in GIR + IPC., Conclusion: Ischemic preconditioning may protect against cell death caused by ischemia and reperfusion.

Purpose: To determine the profile of gene expressions associated with oxidative stress and thereby contribute to establish parameters about the role of enzyme clusters related to the ischemia/reperfusion intestinal injury., Methods: Twelve male inbred mice (C57BL/6) were randomly assigned: Control Group (CG) submitted to anesthesia, laparotomy and observed by 120 min; Ischemia/reperfusion Group (IRG) submitted to anesthesia, laparotomy, 60 min of small bowel ischemia and 60 min of reperfusion. A pool of six samples was submitted to the qPCR-RT protocol (six clusters) for mouse oxidative stress and antioxidant defense pathways., Results: On the 84 genes investigated, 64 (76.2%) had statistic significant expression and 20 (23.8%) showed no statistical difference to the control group. From these 64 significantly expressed genes, 60 (93.7%) were up-regulated and 04 (6.3%) were down-regulated. From the group with no statistical significantly expression, 12 genes were up-regulated and 8 genes were down-regulated. Surprisingly, 37 (44.04%) showed a higher than threefold up-regulation and then arbitrarily the values was considered as a very significant. Thus, 37 genes (44.04%) were expressed very significantly up-regulated. The remained 47 (55.9%) genes were up-regulated less than three folds (35 genes - 41.6%) or down-regulated less than three folds (12 genes - 14.3%)., Conclusion: The intestinal ischemia and reperfusion promote a global hyper-expression profile of six different clusters genes related to antioxidant defense and oxidative stress.

To study whether ischemic preconditioning (IPC) attenuated intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were underwent 60 minutes of I which was produced by occlusion of the superior mesenteric artery, and/or 120 minutes R. The IPC group had the I procedure previously stimulated for 5 minutes and the R for 10 minutes. IPC and sham groups were injected with saline solution (SS) via the femoral vein 5 minutes before the I and R, and for R. After I or I/R, 2-cm jejunal segments were mounted in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were similar in the IPC + I and the IPC + I/R groups, but reduced in the I + SS and the I/R + SS groups. The jejunal enteric nerves were damaged in the I + SS and the I/R + SS groups, but not in the IPC groups. These results suggested that ischemic preconditioning attenuated intestinal dysfunction caused by I and I/R., (Copyright © 2012 Elsevier Inc. All rights reserved.)

To examine whether treatment with L-arginine (ARG), a substrate of nitric oxide biosynthesis, attenuated intestinal dysfunction caused by ischemia (I) and reperfusion (R), we treated rats with ARG (100 mg/kg intravenously) or saline solution (SS) before 60 minutes of I produced by occlusion of the superior mesenteric artery and/or during 120 minutes of R. After I or I/R, we isolated 2-cm jejunal segments for mounting in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl with the use of a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Jejunal contractions were similar in the sham and I+ARG, but reduced in I+SS, I/R+SS, and I/R+ARG groups. Jejunal enteric nerves were damaged in I+SS, IR+SS, and IR+ARG, but not in the I+ARG group, suggesting that ARG attenuate intestinal dysfunctions due to I but not to R., (Copyright © 2012 Elsevier Inc. All rights reserved.)

To study whether treatment with heparin (HEP) attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were treated with HEP (100 U/kg intravenously) or saline solution (SS) before I (60 min), which was produced by occlusion of the superior mesenteric artery, and R (120 min). After I or I/R, we mounted 2-cm jejunal segment in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl, using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were similar in the I + HEP and the I/R + HEP groups, but reduced in the I + SS and the I/R + SS groups. The jejunal enteric nerves were damaged in the I + SS and the I/R + SS, but not in the I + HEP and the I/R + HEP cohorts. These results suggested that HEP attenuated intestinal dysfunction caused by I and I/R., (Copyright © 2012 Elsevier Inc. All rights reserved.)