Comparative study between fructose 1-6 bisphosphate and histidine-tryptophan-ketoglutarate in liver preservation in rats submitted to total cold ischemia

Abstract Purpose To compare Fructose-1,6-Bisphosphate (FBP) to Histidine-Tryptophan-Ketoglutarate (HTK) in liver preservation at cold ischemia. Methods Male rats (Sprague-Dawley: 280-340g) divided into three groups (n=7): Control; Fructose-1,6-bisphosphate (FBP); Histidine-Tryptophan-Ketoglutarate (HTK). Animals underwent laparotomy-thoracotomy for perfusion of livers with saline. Livers were removed and deposited into solutions. Mitochondria were isolated to determine State 3 (S3), State 4 (S4), Respiratory Control Ratio (RCR) and Swelling (S). Liver enzymes (AST, ALT, LDH) were determined in solution. At tissue, Malondialdehyde (MDA) and Nitrate (NOx) were determined. All parameters were analyzed at 0.6 and 24 hours of hypothermic preservation. Statistics analysis were made by Mann-Whitney test (p<0.05). Results Regarding ALT, there was a difference between FBP-6h/HTK-6h, lower in HTK. Regarding AST, there was a significant difference between FBP-24h/HTK-24h, lower in FBP. Regarding NOx, there was a difference between 0h and 6h, as well as 0h and 24h for both solutions. Regarding S3, there was a significant difference in 24h compared to Control-0h for both solutions, and a significant difference between FBP-6h/FBP-24h. Regarding S4, there was a difference between Control-0h/HTK-24h and FBP-24h/HTK-24h, higher in HTK. There was a difference between Control-0h/FBP-24h for Swelling, higher in FBP. Conclusion Fructose-1,6-Bisphosphate showed better performance at nitrate and aspartate aminotransferase compared to histidine-tryptophan-ketoglutarate.

Síntesis y uso de histidinato de cobre en niños con enfermedad de Menkes en México / Synthesis and use of copper histidinate in children with Menkes disease in Mexico

Resumen La enfermedad de Menkes es una patología neurodegenerativa y letal debida a mutaciones génicas de la enzima ATP-7A trasportadora de cobre; se manifiesta por síntomas neurológicos y alteraciones del tejido conectivo de severidad variable. El uso subcutáneo oportuno de histidinato de cobre (Cu-His) es determinante en la calidad de vida. Se reportan las primeras experiencias en México en la síntesis y uso seguro de Cu-His en tres casos en los que corroboramos hipocupremia e hipoceruloplasminemia. Bajo asesoramiento del Hospital for Sick Children, Toronto, Canadá, elaboramos una solución de 500 µg/mL. En los tres casos aplicamos 250 µg de Cu-His, sin efectos indeseables relevantes durante 30 días y observamos las siguientes determinaciones séricas de cobre (Cu en µg/L) y ceruloplasmina (Cp en mg/dL): caso 1, Cu días 0 y 30, 8 y 504 µg/L; Cp días 0 y 30, 4 y 10.75 mg/dL; caso 2, Cu días 0 y 30, < 50 y 502, µg/L; Cp días 0 y 30, 2 y 15 mg/dL; caso 3, Cu días 0 y 30, 3 y 84.2 µg/L; Cp días 0 y 30, 4 y 10.7 mg/dL. En México es posible la síntesis segura de Cu-His y tratar la enfermedad de Menkes, la cual debe ser intencionalmente buscada.

Abstract Menkes disease is a neurodegenerative and lethal pathology caused by gene mutations of the copper-transporting ATP-7A enzyme; it manifests itself by neurological symptoms and connective tissue changes of varying severity. Timely subcutaneous use of copper histidinate (Cu-His) is determinant for quality of life. We report the first experiences in Mexico on Cu-His synthesis and its safe use in 3 cases where hypocupremia and hypoceruloplasminemia were corroborated. With advice of the Hospital for Sick Children of Toronto Canada, we prepared a 500 µg/mL solution. In all three cases were 250 µg of Cu-His applied without relevant undesirable effects for 30 days. Serum copper (Cu, expressed in µg/L) and ceruloplasmin (Cp, in mg/dL) were determined: case 1, Cu days 0 and 30, 8 and 504 µg/L; Cp days 0 and 30, 4 and 10.75 mg/dL; case 2, Cu days 0 and 30, <50 and 502 µg/L; Cp days 0 and 30, 2 and 15 mg/dL; case 3, Cu days 0 and 30, 3 and 84.2 µg/L; Cp days 0 and 30, 4 and 10.7 mg/dL. In Mexico, it is possible to safely synthesize Cu-His and treat MD, which must be intentionally sought.

Membrane adsorber for endotoxin removal

ABSTRACT The surface of flat-sheet nylon membranes was modified using bisoxirane as the spacer and polyvinyl alcohol as the coating polymer. The amino acid histidine was explored as a ligand for endotoxins, aiming at its application for endotoxin removal from aqueous solutions. Characterization of the membrane adsorber, analysis of the depyrogenation procedures and the evaluation of endotoxin removal efficiency in static mode are discussed. Ligand density of the membranes was around 7 mg/g dry membrane, allowing removal of up to 65% of the endotoxins. The performance of the membrane adsorber prepared using nylon coated with polyvinyl alcohol and containing histidine as the ligand proved superior to other membrane adsorbers reported in the literature. The lack of endotoxin adsorption on nylon membranes without histidine confirmed that endotoxin removal was due to the presence of the ligand at the membrane surface. Modified membranes were highly stable, exhibiting a lifespan of approximately thirty months.

RESUMO A superfície de membranas planas de nylon foi modificada utilizando-se bisoxirano como espaçador e poli(álcool vinílico) para recobrimento das membranas. O aminoácido histidina foi utilizado como ligante para endotoxinas, visando à sua aplicação na remoção de endotoxinas a partir de soluções aquosas. São discutidas as etapas de caracterização do adsorvedor com membranas, análise do procedimento de despirogenização e avaliação da eficiência de remoção em modo estático. A densidade de ligantes nas membranas foi em torno de 7 mg/g membrana (massa seca), permitindo uma remoção de endotoxinas de até 65%. O desempenho das membranas preparadas com nylon e recobertas com poli(álcool vinílico) contendo histidina como ligante foi superior ao de outros adsorvedores com membranas descritos na literatura. A ausência de adsorção de endotoxinas em membranas sem histidina confirma que a remoção das endotoxinas deve-se exclusivamente à presença do ligante na superfície da membrana. As membranas modificadas mostraram-se bastante estáveis, exibindo um tempo de vida superior a 30 dias.

Menkes disease: importance of diagnosis with molecular analysis in the neonatal period / Doença de Menkes: importância do diagnóstico com análise molecular no período neonatal

Summary Menkes disease is a congenital disorder caused by changes in copper metabolism derived from mutations in the ATP7A gene. It is characterized by physical and neurological alterations. In the neonatal period, these alterations can be nonspecific, which makes early diagnosis a challenge. Diagnosis can be suspected when there are low levels of ceruloplasmin and serum copper. Molecular analysis confirms the diagnosis. Treatment is parenteral administration of copper histidine. We report a familial case with molecular confirmation. The proband had clinical and biochemical suspicious. Treatment with copper histidine was indicated, but initiated at the age of 2 months and 27 days only. He did not present improvements and died at 6 months. The mother became pregnant again, a male fetus was identified and copper histidine was manufactured during pregnancy. He was born healthy, biochemical markers were reduced and treatment was indicated. Molecular analysis was performed confirming mutation in both the mother and the proband, while the other son did not have mutation, so treatment was discontinued. We support the clinical relevance of molecular confirmation for the correct diagnosis and genetic counseling, once clinical findings in the neonatal period are nonspecific and early treatment with parenteral copper histidine must be indicated.

Resumo A doença de Menkes é causada por uma alteração genética no metabolismo do cobre, por mutações no gene ATP7A. Caracteriza-se por alterações neurológicas e no exame físico. No período neonatal, essas alterações podem ser inespecíficas, o que torna o diagnóstico precoce um desafio. O diagnóstico pode ser suspeitado quando há baixos níveis séricos de cobre e ceruloplasmina. A análise molecular confirma o diagnóstico, e o tratamento deve ser feito com histidina de cobre. Nós relatamos um caso familial de doença de Menkes. O probando apresentava quadro clínico e alterações bioquímicas compatíveis com a doença de Menkes, em consulta com 1 mês de vida. O tratamento foi indicado, mas apenas iniciado com 2 meses e 27 dias. Ele não apresentou melhora clínica e veio a óbito com 6 meses. A mãe teve uma nova gestação, foi identificado um feto do sexo masculino e foi solicitada a manipulação da histidina de cobre ainda durante a gestação. O bebê nasceu saudável, os marcadores bioquímicos estavam diminuídos e o tratamento com histidina de cobre foi indicado. Realizamos a análise molecular, que confirmou mutação no gene ATP7A na mãe e no probando; porém, o outro filho não apresentava mutação e o tratamento foi interrompido. Nós defendemos a importância clínica da confirmação molecular para o correto diagnóstico e o aconselhamento genético da doença de Menkes, uma vez que os achados clínicos e as alterações bioquímicas no período neonatal são inespecíficos, e o tratamento com histidina de cobre parenteral deve ser rapidamente instituído.

Dosaje de una glicoproteína rica en histidina en el lavado broncoalveolar de pacientes con enfermedades intersticiales difusas de pulmón / Dosage of Histidine Rich Glicoprotein in the Bronchoalveolar Lavage of Patients with Diffuse Interstitial Lung Disease

Introducción: La proteína rica en histidina (HRG) se encuentra en el plasma en altas concentraciones (100-150 μg/ml) y puede interaccionar con una gran variedad de moléculas. Se ha sugerido que esta proteína podría actuar como un reactante de fase aguda negativa, e incluso que podría participar en la proliferación de fibroblastos utilizando líneas celulares. Objetivo: Analizar los niveles de HRG en muestras de lavado broncoalveolar (LBA) de pacientes con enfermedad intersticial pulmonar difusa (EIPD) y evaluar su relación con la severidad de la enfermedad. Materiales y métodos: Se incluyeron muestras de 30 pacientes con EIPD y 17 sujetos control. Se dosaron los niveles de HRG en muestras de LBA por ELISA. Se recolectaron los datos función pulmonar. Resultados: Se encontró un aumento en la concentración de HRG en el LBA de pacientes con EIPD comparado con los sujetos control. Más aún, la concentración de HRG en el LBA fue inversamente proporcional a la capacidad vital forzada (CVF) de los pacientes (spearman r:-0.35; p < 0.05). Sin embargo, el análisis de cada subtipo de EIPD demostró que solo aquellos con fibrosis pulmonar idiopática (FPI) presentaron un incremento significativo respecto del grupo control (5.631.0 ± 303.7pg/ml vs 2.296.0 ± 349.4pg/ ml; p < 0.01). Conclusiones: Se describe por primera vez un aumento del nivel de HRG en pacientes con FPI, aunque nuevos estudios son requeridos para evaluar su rol como biomarcador asociado a la severidad o progresión de la enfermedad.

Introduction: The concentration of Histidine Rich Glycoprotein (HRG) in plasma is high (100-150 μg/ml). HRG interacts with a wide range of molecules. It has been suggested that this protein could act as a negative reactant acute protein and would be able to modulate fibroblast proliferation using cell lines. Objective: To analyze the levels of HRG in Bronchoalveolar Lavage (BAL) samples from patients with Interstitial Lung Diseases (ILD) and to evaluate its relationship with illness severity. Materials and Methods: Thirty patients with ILD and 17 control subjects were included. HRG was measured by ELISA. Pulmonary functions tests data were collected. Results: Increased levels of HRG in BAL samples from ILD patients were found compared with control subjects. Moreover, the levels of HRG showed an inverse correlation with the Forced Vital Capacity (FVC) values from patients with ILD (spearman r: -0.35; p < 0.05). However, when each subtype of ILD was analyzed, we observed that only patients with Idiopathic Pulmonary Fibrosis (IPF) showed a significant increase in levels of HRG compared with the control group (5.631,0 ± 303,7 pg/ml vs 2.296,0 ± 349,4 pg/ml; p < 0.01). Conclusions: This is the first time that increase of HRG levels from patients with IPF is described. Nevertheless, new studies are required to analyze its role as biomarker associated with severity or progression of the illness.

Suicide attempts among children and adolescents: partial or total injury? / Tentativa de suicídio infanto-juvenil: lesão da parte ou do todo?

This study sought to verify the records on file and the number of cases of attempted suicide among children and adolescents who were attended by Emergency Care health professionals in the municipality of Matozinhos, Minas Gerais, Brazil. Documentary and descriptive research was conducted, the data for which was collected by means of an investigation of Outpatient Records from 2008 to 2010. Of the 73,000 files evaluated, those dealing with cases of attempted suicide among children and adolescents between the age of 3 and 18 years were selected. It was revealed that the health professionals, particularly physicians and nurses, fail to register the cases appropriately, invalidating information about the problem and potential prevention measures. The conclusion reached was that underreporting and the discrepancy of the diagnoses which were not duly referred to the competent agencies require rethinking and reviewing medical practices, and taking a systematic and careful look to address the individual as a complex whole.

Neste estudo procurou-se verificar o registro e o número de casos de tentativa de suicídio entre crianças e adolescentes do município de Matozinhos, Minas Gerais, Brasil, que foram atendidos pelos profissionais de saúde do Pronto-Atendimento. Trata-se de uma pesquisa documental e descritiva, cuja coleta dos dados ocorreu por meio de investigação nas Fichas Ambulatoriais, no período de 2008 a 2010. Das 73.000 fichas levantadas, selecionaram-se aquelas que tratavam de casos de tentativa de suicídio entre crianças e adolescentes do município, com idades entre três e 18 anos. Percebeu-se que os profissionais de saúde, mais especificamente os médicos e enfermeiros, não registram os casos de forma adequada, inviabilizando a informação sobre o problema e as medidas de prevenção. Concluiu-se que a subnotificação, a discrepância dos diagnósticos e o não encaminhamento aos órgãos competentes exigem repensar e rever a prática médica e dirigir um olhar sistematizado e cuidadoso para perceber o sujeito como um todo complexo.

Comparação da solução de histidina-triptofano-alfacetoglutarato com histidina-triptofano-glutamato como agentes cardioplégicos em corações isolados de ratos: estudo imuno-histoquímico / Comparison of the solution of histidine-tryptophan-alfacetoglutarate with histidine-tryptophan-glutamate as cardioplegic agents in isolated rat hearts: an immunohistochemical study

Introdução: A parada do coração durante a cirurgia cardíaca é procedimento comum e permite que o cirurgião realize os procedimentos cirúrgicos em ambiente isento de sangue e movimento. Os autores comparam, em modelo de coração isolado de rato, uma nova solução cardioplégica com histidina-triptofano-glutamato (grupo 2) com a histidina-triptofano-alfacetoglutarato (grupo 1) já utilizada de rotina por alguns cirurgiões cardíacos. Objetivo: Avaliar por análise imuno-histoquímica a caspase, a IL-8 e KI-67 em corações isolados de ratos. Métodos: 20 ratos machos de raça Wistar foram anestesiados e heparinizados. O tórax foi aberto, realizado cardiectomia e infundido 40 ml/kg de solução cardioplégica apropriada. Os corações foram mantidos por 2 horas na mesma solução a 4ºC e, após esse período, colocados em aparato de Langendorff por 30 minutos com solução de Ringer Locke. Foram feitas análises imuno-histoquímicas para caspase, IL-8 e KI-67. Resultados: A concentração de caspase estava menor no grupo 2 e da KI-67 estava mais elevada no grupo 2, ambos com P<0,05. Não houve diferença estatística entre os valores de IL-8 entre os grupos. Conclusão: A solução com histidina-triptofano-glutamato foi melhor que a com histidina-triptofano-cetoglutarato, pois reduziu a caspase (apoptose), aumentou o KI-67 (proliferação celular) e não apresentou valores diferentes de IL-8 (inflamação e necrose) que no grupo 1. Isso sugere que a solução histidina-triptofano-glutamato foi mais eficiente que a histidina-triptofano-cetoglutarato na preservação dos cardiomiócitos dos corações de ratos. .

Introduction: Cardiac arrest during heart surgery is a common procedure and allows the surgeon to perform surgical procedures in an environment free of blood and movement. Using a model of isolated rat heart, the authors compare a new cardioplegic solution containing histidine-tryptophan-glutamate (group 2) with the histidine-tryptophan-alphacetoglutarate (group 1) routinely used by some cardiac surgeons. Objective: To assess caspase, IL-8 and KI-67 in isolated rat hearts using immunohistochemistry. Methods: 20 Wistar male rats were anesthetized and heparinized. The chest was opened, cardioctomy was performed and 40 ml/kg of the appropriate cardioplegic solution was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter, placed in the Langendorff apparatus for 30 minutes with Ringer-Locke solution. Immunohistochemistry analysis of caspase, IL-8, and KI-67 were performed. Results: The concentration of caspase was lower in group 2 and Ki-67 was higher in group 2, both P<0.05. There was no statistical difference between the values of IL-8 between the groups. Conclusion: Histidine-tryptophan-glutamate solution was better than histidine-tryptophan-alphacetoglutarate solution because it reduced caspase (apoptosis), increased KI-67 (cell proliferation), and showed no difference in IL-8 levels compared to group 1. This suggests that the histidine-tryptophan-glutamate solution was more efficient than the histidine-tryptophan-alphacetoglutarate for the preservation of hearts of rat cardiomyocytes. .

Comparison of Celsior and Perfadex lung preservation solutions in rat lungs subjected to 6 and 12 hours of ischemia using an ex-vivo lung perfusion system

OBJECTIVE: This study evaluated the performance of lungs that were preserved with different solutions (Celsior, Perfadex or saline) in an ex vivo rat lung perfusion system. METHODS: Sixty Wistar rats were anesthetized, anticoagulated and randomized into three groups (n = 20). The rats were subjected to antegrade perfusion via the pulmonary artery with Perfadex, Celsior, or saline, followed by 6 or 12 hours of ischemia (4ºC, n = 10 in each group). Respiratory mechanics, gas exchange and hemodynamics were measured at 10-minute intervals during the reperfusion of heart-lung blocks in an ex vivo system (IL2-Isolated Perfused Rat or Guinea Pig Lung System, Harvard Apparatus, Holliston, Massachusetts, USA; Hugo Sachs Elektronik, Germany) for 60 minutes. The lungs were prepared for histopathology and evaluated for edema following reperfusion. Group comparisons were performed using ANOVA and the Kruskal-Wallis test with a 5% level of significance. RESULTS: Gas exchange was not significantly different between lungs perfused with either Perfadex or Celsior at the same ischemic times, but it was very low in lungs that were preserved with saline. Airway resistance was greater in the lungs that were preserved for 12 hours. Celsior lungs that were preserved for 6 and 12 hours exhibited lower airway resistance (p = 0.01) compared to Perfadex lungs. Pulmonary artery pressure was not different between the groups, and no significant differences in histopathology and apoptosis were observed between the groups. CONCLUSIONS: Lungs that were preserved with Celsior or Perfadex exhibited similar gas exchange and histopathological findings. Airway resistance was slightly lower in the Celsior-preserved lungs compared with the Perfadex-preserved lungs.

Histidinemia atípica y desarrollo cognitivo / Atypical hystidinemia and the cognitive development

Introducción: la histidinemia es un defecto metabólico dentro del grupo de aminoacidemias. El defecto enzimático de la histidasa (histidin-amono-liasa) provoca alta concentración de histidina en sangre, líquido cefalorraquídeo, en la orina y en el sudor. Métodos: un estudio de caso muestra el desarrollo evolutivo de un niño con histidinemia atípica y el impacto de la rehabilitación desde la edad temprana hasta la edad escolar. Resultados: la condición patológica causada por la histidinemia atípica limita el desarrollo motor, neurológico, neuropsicológico, conductual y escolar del niño. La rehabilitación temprana muestra que las habilidades primarias de la marcha se adquieren en la etapa esperada, pero los problemas motores complejos mantienen su limitación en el desarrollo. Las dificultades en el lenguaje oral persisten en toda la edad temprana, la rehabilitación posibilita su perfeccionamiento con la edad. Conclusiones: la histidinemia atípica muestra en el desarrollo alteraciones neurológicas, neuropsicológicas, neurofisiológicas, conductuales y académicas. La rehabilitación temprana brinda mejores condiciones de vida del infante. El carácter crónico de la enfermedad posibilita un pronóstico negativo en áreas esenciales como la conducta y la vida escolar(AU)

Introduction: histidinemia is a metabolic defect within the group of aminoacidemias. The enzymatic defect of histidase (histidin-amono-lyase) cause high histidine concentration in the blood, the cerebrospinal fluid, in urine, and sweat. Methods: a case study showed the developmental evolution of a child with atypical histidinemia and the impact of rehabilitation from early age to school age. Results: the pathological condition caused by atypical histidinemia limits the motor, neurological, neuropsychological, behavioural and educational development of the child. The early rehabilitation shows that primary gait abilities are acquired in the expected phase, but the complex motor problems remained in the development phase. The language difficulties persist throughout the early childhood, but rehabilitation makes it possible to improve oral expression as age increases. Conclusions: atypical histidinemia reveals neurological, neuropsychological, neurophysiological, behavioural and academic alterations in the development of the child. The early rehabilitation provides better living conditions to the child. The chronic nature of the disease indicates a negative prognosis in essential areas such as behaviour and education(AU)

Comparative experimental study of myocardial protection with crystalloid solutions for heart transplantation / Estudo comparativo experimental da proteção miocárdica com soluções cristalóides para transplante cardíaco

BACKGROUND: There is a growing need to improve myocardial protection, which will lead to better performance of cardiac operations and reduce morbidity and mortality. Therefore, the objective of this study was to compare the efficacy of myocardial protection solution using both intracellular and extracellular crystalloid type regarding the performance of the electrical conduction system, left ventricular contractility and edema, after being subjected to ischemic arrest and reperfusion. METHODS: Hearts isolated from male Wistar (n=32) rats were prepared using Langendorff method and randomly divided equally into four groups according the cardioprotective solutions used Krebs-Henseleit-Buffer (KHB), Bretschneider-HTK (HTK), St. Thomas-1 (STH-1) and Celsior (CEL). After stabilization with KHB at 37ºC, baseline values (control) were collected for heart rate (HR), left ventricle systolic pressure (LVSP), maximum first derivate of rise left ventricular pressure (+dP/dt), maximum first derivate of fall left ventricular pressure (-dP/dt) and coronary flow (CF). The hearts were then perfused at 10ºC for 5 min and kept for 2 h in static ischemia at 20ºC in each cardioprotective solution. Data evaluation was done using analysis of variance in completely randomized One-Way ANOVA and Tukey's test for multiple comparisons. The level of statistical significance chosen was P<0.05. RESULTS: HR was restored with all the solutions used. The evaluation of left ventricular contractility (LVSP, +dP/ dt and -dP/dt) showed that treatment with CEL solution was better compared to other solutions. When analyzing the CF, the HTK solution showed better protection against edema. CONCLUSION: Despite the cardioprotective crystalloid solutions studied are not fully able to suppress the deleterious effects of ischemia and reperfusion in the rat heart, the CEL solution had significantly higher results followed by HTK>KHB>STH-1.

INTRODUÇÃO: Existe crescente necessidade de aprimorar a proteção miocárdica, para melhor desempenho das operações cardíacas e diminuição da morbimortalidade. Portanto, o objetivo deste estudo foi comparar a eficácia da proteção miocárdica usando tanto solução cristaloide tipo intracelular como extracelular quanto ao desempenho do sistema de condução elétrica, contratilidade do ventrículo esquerdo e edema, após parada isquêmica e posterior reperfusão. MÉTODOS: Corações isolados de ratos Wistar foram montados em Langendorff e aleatoriamente divididos em quatro grupos. de acordo com as soluções cardioprotetoras utilizadas Krebs-Henseleit-Buffer (KHB), Bretschneider-HTK (HTK), St. Thomas-1(STH-1) e Celsior (CEL). Após a estabilização com KHB a 37ºC, valores basais (controle) foram coletados para frequência cardíaca (FC), pressão sistólica do ventrículo esquerdo (PSVE), derivada máxima de aumento da pressão ventricular esquerda (+dP/dt), derivada máxima de queda da pressão ventricular esquerda (-dP/dt) e fluxo coronariano (FCo). Os corações foram então perfundidos a 10ºC por 5 min e mantidos por 2 h em isquemia estática a 20ºC em cada solução cardioprotetora. Avaliação dos dados foi por análise de variância inteiramente casualizados em One-Way ANOVA e teste de Tukey para comparações múltiplas. O nível de significância estatística escolhido foi P<0,05. RESULTADOS: Houve recuperação da FC com todas as soluções utilizadas. A avaliação da contratilidade ventricular esquerda (PSVE, +dP/dt e -dP/dt) demonstrou que o tratamento com a solução CEL foi melhor em comparação às outras soluções. Ao analisar o CF, a solução HTK indicou melhor proteção contra edema. CONCLUSÃO: Apesar das soluções cristaloides cardioprotetoras estudadas não serem capazes de suprimir os efeitos deletérios da isquemia e reperfusão no coração de ratos, a solução CEL apresentou resultado superior seguido por HTK>KHB>STH-1.

Effects of ischemic preconditioning associated to different preservation solutions in protecting the intestinal graft / Efeitos do precondicionamento isquêmico associado a diferentes soluções de preservação na proteção do enxerto intestinal

PURPOSE: To evaluate the effects of ischemic preconditioning (IPC) associate with different preservation solutions, in the protecting of gut. METHODS: Four groups of 14 rats underwent laparotomy and collecting 20 cm of ileum, for preservation, at 4ºC, in Belzer (Belz), Ringer (RL), Celsior (Cs) and Custodiol (Cust) solutions, for 24 hours. Prior to collection, half of the animals in each group were subjected to IPC. During preservation, in the periods of zero, 12, 18 and 24 hours, were conducted evaluating the degree of mucosal injury and dosage of malondialdehyde acid (MDA). RESULTS: In all periods the RL group, with and without IPC, presented MDA values higher than the Belz and Cs. The degree of mucosal injury in the non-ipc RLgroup with 12h preservation was higher than the others; with 18 and 24h, the RL and Cust had higher degrees of damage than Cs and Belz. With IPC, in all periods, the group Cs and Belz had lower degrees of injury. CONCLUSION: The Celsior and Belzer solutions had better protective effects on the gut and these effects were enhanced by IPC.

OBJETIVO: Avaliar os efeitos do precondicionamento isquêmico (PCI) associado a diferentes soluções de preservação, na proteção do intestino delgado. MÉTODOS: Quatro grupos de 14 ratos Wistar, foram submetidos à laparotomia e coleta de 20 cm de íleo, para preservação, a 4ºC, nas soluções de Belzer (Belz), Ringer (RL), Celsior (Cs) e Custodiol (Cust) por 24 horas. Previamente à coleta, em metade dos animais de cada grupo, o intestino foi submetido ao PCI. Durante a preservação, nos períodos de Zero, 12, 18 e 24 horas, foram realizados avaliação do grau de lesão da mucosa e dosagem do ácido malondialdeído (MDA). RESULTADOS: Em todos os períodos o grupo RL, sem e com pci, apresentou valores maiores de MDA do que o Belz e Cs. O grau de lesão da mucosa nos grupos sem pci com preservação de 12h, no grupo RL, foi maior que nos demais; com 18h e 24h o grupo RL e Cust apresentaram maiores graus de lesão do que Cs e Belz. Com o pci, em todos os períodos, os grupos Belz e Cs apresentaram menores graus de lesão CONCLUSÃO: As Soluções Celsior e Belzer tiveram melhores efeitos na proteção do intestino e estes efeitos foram incrementados pelo precondicionamento isquêmico.

Comparative analysis of two component signal transduction systems of the Lactobacillus acidophilus group

The Lactobacillus acidophilus group is a phylogenetically distinct group of closely related lactobacilli. Members of this group are considered to have probiotic properties and occupy different environmental niches. Bacteria generally sense and respond to environmental changes through two component systems (TCSs) which consist of a histidine protein kinase (HPK) and its cognate response regulator (RR). With the use of in silico techniques, the five completely sequenced L. acidophilus group genomes were scanned in order to predict TCSs. Five to nine putative TCSs encoding genes were detected in individual genomes of the L. acidophilus group. The L. acidophilus group HPKs and RRs were classified into subfamilies using the Grebe and Stock classification method. Putative TCSs were analyzed with respect to conserved domains to predict biological functions. Putative biological functions were predicted for the L. acidophilus group HPKs and RRs by comparing them with those of other microorganisms. Some of TCSs were putatively involved in a wide variety of functions which are related with probiotic ability, including tolerance to acid and bile, production of antimicrobial peptides, resistibility to the glycopeptide antibiotic vancomycin, and oxidative condition.

L-histidine provokes a state-dependent memory retrieval deficit in mice re-exposed to the elevated plus-maze

The effects of L-histidine (LH) on anxiety and memory retrieval were investigated in adult male Swiss Albino mice (weight 30-35 g) using the elevated plus-maze. The test was performed on two consecutive days: trial 1 (T1) and trial 2 (T2). In T1, mice received an intraperitoneal injection of saline (SAL) or LH before the test and were then injected again and retested 24 h later. LH had no effect on anxiety at the dose of 200 mg/kg since there was no difference between the SAL-SAL and LH-LH groups at T1 regarding open-arm entries (OAE) and open-arm time (OAT) (mean ± SEM; OAE: 4.0 ± 0.71, 4.80 ± 1.05; OAT: 40.55 ± 9.90, 51.55 ± 12.10, respectively; P > 0.05, Kruskal-Wallis test), or at the dose of 500 mg/kg (OAE: 5.27 ± 0.73, 4.87 ± 0.66; OAT: 63.93 ± 11.72, 63.58 ± 10.22; P > 0.05, Fisher LSD test). At T2, LH-LH animals did not reduce open-arm activity (OAE and OAT) at the dose of 200 mg/kg (T1: 4.87 ± 0.66, T2: 5.47 ± 1.05; T1: 63.58 ± 10.22; T2: 49.01 ± 8.43 for OAE and OAT, respectively; P > 0.05, Wilcoxon test) or at the dose of 500 mg/kg (T1: 4.80 ± 1.60, T2: 4.70 ± 1.04; T1: 51.55 ± 12.10, T2: 43.88 ± 10.64 for OAE and OAT, respectively; P > 0.05, Fisher LSD test), showing an inability to evoke memory 24 h later. These data suggest that LH does not act on anxiety but does induce a state-dependent memory retrieval deficit in mice.

L-histidine enhances learning in stressed zebrafish

The aim of the present study was to determine the effect of the histaminergic precursor L-histidine and the H3 receptor antagonist thioperamide on the learning process of zebrafish submitted or not to confinement stress. On each of the 5 consecutive days of experiment (D1, D2, D3, D4, D5), animals had to associate an interruption of the aquarium air supply with food offering. Non-stressed zebrafish received an intraperitoneal injection of 100 mg/kg L-histidine, 10 mg/kg thioperamide or saline after training. Stressed animals received drug treatment and then were submitted to confinement stress for 1 h before the learning procedure. Time to approach the feeder was measured (in seconds) and was considered to be indicative of learning. A decrease in time to approach the feeder was observed in the saline-treated group (D1 = 141.92 ± 13.57; D3 = 55 ± 13.54), indicating learning. A delay in learning of stressed animals treated with saline was observed (D1 = 217.5 ± 25.66). L-histidine facilitated learning in stressed (D1 = 118.68 ± 13.9; D2 = 45.88 ± 8.2) and non-stressed (D1 = 151.11 ± 19.20; D5 = 62 ± 14.68) animals. Thioperamide inhibited learning in non-stressed (D1 = 110.38 ± 9.49; D4 = 58.79 ± 16.83) and stressed animals (D1 = 167.3 ± 26.39; D5 = 172.15 ± 27.35). L-histidine prevented the increase in blood glucose after one session of confinement (L-histidine = 65.88 ± 4.50; control = 53 ± 3.50 mg/dL). These results suggest that the histaminergic system enhances learning and modulates stress responses in zebrafish.

L-histidine reduces inhibitory avoidance in Carassius auratus submitted to cerebellar ablation

The effect of post-training treatment with L-histidine (LH) on the memory consolidation of inhibitory avoidance was investigated in Carassius auratus submitted to cerebellar ablation. The inhibitory avoidance procedure included 3 days: one habituation day, one training day (5 trials, T1-T5) and one test day. On the training day, each fish was placed individually in a white compartment separated from a black compartment by a sliding door. When the fish crossed into the black compartment, a weight was dropped in front of it (aversive stimulus) and the time to cross was recorded. Saline or LH (100 mg/kg) was injected intraperitoneally 10 min after the trials. Data were log10 transformed and analyzed by ANOVA and the Student-Newman-Keuls test (P < 0.05). In T5, all groups [ablation/LH (N = 15; 189.60 ± 32.52), ablation/saline (N = 14; 204.29 ± 28.95), sham/LH (N = 14; 232.36 ± 28.15), and sham/saline (N = 15; 249.07 ± 25.82)] had similar latencies that were significantly higher than T1 latencies [ablation/LH (89.33 ± 20.41), ablation/saline (97.00 ± 25.16), sham/LH (73.86 ± 18.42), and sham/saline (56.71 ± 17.59)], suggesting acquisition of inhibitory avoidance. For the test, there was a significant reduction in latencies of ablation/LH (61.53 ± 17.70) and sham/saline (52.79 ± 25.37) groups compared to the ablation/saline (213.64 ± 29.57) and sham/LH (199.43 ± 24.48) groups, showing that cerebellum ablation facilitated retention of inhibitory avoidance and LH reversed the effect of ablation. The results support other evidence that LH impairs memory consolidation and/or reduces the interpretation of aversion value.

Recombinant tegumental protein Shistosoma japonicum very lowdensity lipoprotein binding protein as a vaccine candidate against Schistosoma japonicum

A polyhistidine-tagged recombinant tegumental protein Schistosoma japonicum very lowdensity lipoprotein binding protein (SVLBP) from adult Schistosoma japonicum was expressed in Escherichia coli. The affinity purified rSVLBP was used to vaccinate mice. The worm numbers and egg deposition recovered from the livers and veins of the immunized mice were 33.5 percent and 47.6 percent less than that from control mice, respectively (p<0.05). There was also a marked increase in the antibody response in vaccinated mice: the titer of IgG1 and IgG2a, IgG2b in the vaccinated group was significantly higher than that in the controls (>1:6,400 in total IgG). In a comparison of the reactivity of sera from healthy individuals and patients with rSVLBP, recognition patterns against this parasite tegumental antigen varied among different groups of the individuals. Notably, the average titres of anti-rSVLBP antibody in sera from faecal egg-negative individuals was significantly higher than that in sera from the faecal egg-positives, which may be reflect SVLBP-specific protection. These results suggested that the parasite tegumental protein SVLBP was a promising candidate for further investigation as a vaccine antigen for use against Asian schistosomiasis.

Histidines 13 and 14 in the Aâ sequence are targets for inhibition of Alzheimer's disease Aâ ion channel and cytotoxicity

The fact that Alzheimer's beta amyloid (Aâ) peptides forms cation channels in lipid bilayers was discovered during the course of our experiments in the laboratory of "Guayo" Rojas at NIH in Bethesda, Maryland (USA). Recently, we found that the Aâ ion channel could be blocked selectively with small peptides that copy the amino acid sequence of the predicted mouth region of the Aâ channel pore. We now have searched for the essential amino acid residues required for this blocking effect by mutations. We found that the ability of peptides to block Aâ channel activity could be lost by replacement of histidines 13 and 14 by alanine or lysine. The amino acid substitution also resulted in the loss of the capacity of the peptides to protect cells from Aâ cytotoxicity. These data thus contribute to the definition of the region of the Aâ sequence that participates in the formation of the channel pore. Additionally, these data support the hypothesis that the ion channel activity of Ab contributes significantly to the cytotoxic properties of Aâ. These data also emphasize the potential value in using inhibition of Aâ ion channel activity as an end point for Alzheimer's disease drug discovery.

Viral membrane fusion: is glycoprotein G of rhabdoviruses a representative of a new class of viral fusion proteins?

Enveloped viruses always gain entry into the cytoplasm by fusion of their lipid envelope with a cell membrane. Some enveloped viruses fuse directly with the host cell plasma membrane after virus binding to the cell receptor. Other enveloped viruses enter the cells by the endocytic pathway, and fusion depends on the acidification of the endosomal compartment. In both cases, virus-induced membrane fusion is triggered by conformational changes in viral envelope glycoproteins. Two different classes of viral fusion proteins have been described on the basis of their molecular architecture. Several structural data permitted the elucidation of the mechanisms of membrane fusion mediated by class I and class II fusion proteins. In this article, we review a number of results obtained by our laboratory and by others that suggest that the mechanisms involved in rhabdovirus fusion are different from those used by the two well-studied classes of viral glycoproteins. We focus our discussion on the electrostatic nature of virus binding and interaction with membranes, especially through phosphatidylserine, and on the reversibility of the conformational changes of the rhabdovirus glycoprotein involved in fusion. Taken together, these data suggest the existence of a third class of fusion proteins and support the idea that new insights should emerge from studies of membrane fusion mediated by the G protein of rhabdoviruses. In particular, the elucidation of the three-dimensional structure of the G protein or even of the fusion peptide at different pH's might provide valuable information for understanding the fusion mechanism of this new class of fusion proteins.

Evaluación bacteriológica y contenido de histamina en pescado desmenuzado precocido en Venezuela / Bacteriological evaluation and histamine content in minced pre-cooked fish in Venezuela

Se determinó la calidad bacteriológica y el contenido de histamina en tres marcas comerciales (A, B, C) de pescado desmenizado precocido (mojito) disponible en la ciudad de Maracaibo. Se analizaron 42 muestras (14 de cada marca, tres muestreos), a las cuales se determinó Coliformes Totales (CT), Escherichia coli (EC), Recuento de Aerobios Mesófilos (RAM) y Microorganismos Psicrófilo (MP), según COVENIN; bacterias productoras de histamina (BPH), según Niven modificado por Yoshinaga. Concentración de histamina e histidina, por Cromatografía Líquida de Alta Resolución. El RAM varió entre 4,7 y 7,6 y MP entre 5,6 y 7,9 log UFC/g. Las marcas A y B estuvieron por encima de los límites permitidos por COVENIN y el Servicio Nacional de Pesca de Chile (SERNAPESCA). Los valores de CT variaron entre 2,3 y 2,8 log NMP/g, las tres marcas sobrepasaron los límites establecidos por SERNAPESCA. En las marcas A y B se aislaron EC, en límites inferiores a la norma COVENIN, no así para SERNAPESCA, la cual establece que ésta no debe encontrarse. Las BPH en las marcas A y B pertenecían principalmente a la familia Enterobacteriaceae, con porcentajes de 65,38 y 55,55, respectivamente, mientras que en C se observó igual proporción de enterobacterias y bacilos Gram negativos no fermentadores de la glucosa (BGNNFG), 42,85 por ciento. No se detectaron concentraciones de histamina e histidina. En conclusión las marcas A y B, presentaron una deficiente calidad bacteriológica, posiblemente debido al proceso de desmenuzado manual. La presencia de BPH sugiere contaminación post-cocción durante el desmenuzado

Role of the Parasight-F test in the diagnosis of complicated Plasmodium falciparum malarial infection

An evaluation was made of the diagnostic efficacy and utility of the Parasight-F test in diagnosing Plasmodium falciparum malaria, compared with conventional microscopy, particularly in severe and complicated cases. This study was designed as a prospective, case control hospital-based study. Febrile patients suspected to be suffering from malaria were selected randomly and were subjected to peripheral smear examinations (thick and thin) and Parasight-F tests till the required number of at least 30 cases of P. falciparum infection were identified, including at least 15 complicated cases. In addition 20 cases of P. vivax malarial infection as well as 20 healthy age and sex-matched individuals were taken as two control groups. The outcome measure was the number of cases with positive Parasight-F test results compared with conventional microscopy. Thirty-two patients with P. falciparum malaria were identified, with 15 severe and complicated cases. Peripheral smears were positive in 29 (91 percent) of these, while parasight-F test was positive in 31 out of 32 (97 percent) cases. Parasites were detected only by bone marrow examination in one case. Diagnostic sensitivity and specificity of peripheral smears for detecting falciparum infection were 90.6 percent and 100 percent respectively while that of the Parasight-F test were 96.8 percent and 100 percent, respectively (P>.05). The Parasight-F test has high sensitivity and specificity in diagnosing P. falciparum malarial infection, comparable to or even higher than microscopy exams, particularly in severe and complicated cases, with additional advantages of speed, simplicity and objectivity.