Efeitos do alopurinol e precondicionamento na apoptose devido a isquemia-reperfusão em duplo segmento de jejuno em cães / Effects of allopurinol and preconditioning on apoptosis due to ischemia-reperfusion on a double jejunum-segment canine model

PURPOSE: To investigate the duration of apoptosis caused by ischemia-reperfusion in the intestine in a new double jejunum-segment model, and to analyze the protective effects of allopurinol or ischemic preconditioning (IPC). METHODS: In Experiment I for harvesting the double jejunum-segment model after laparotomy a 30-cm-long jejunum part was selected on mongrel dogs (n=24). End-to-end anastomoses were performed at both ends and in the middle of the jejunum part, creating two equal segments. In one segment ischemia was induced by occluding the supplying vessels, the other segment served as control. Tissue samples for detecting apoptosis were taken at 30th minutes, 1st, 2nd, 4th, 6th, 8th, 12th and 24th hours of reperfusion. In Experiment II using the same model the 4-hour reperfusion time period, allopurinol (50 mg/kg) pre-treated and IPC (3 cycles of 5x1) groups (n=5 per each) were also investigated. RESULTS: In Experiment I the greatest apoptotic activity was detected at the 4th and 6th hour of reperfusion (14.2 ± 1.31 and 16.3 ± 1.05 per visual field at 40x magnification). In Experiment II Using the 4-hour reperfusion time period allopurinol pre-treatment increased the apoptotic activity (10.72 ± 0.47 per 50 intestinal villi) approximately two-fold than the IPC (6.72 ± 0.46 per 50 intestinal villi) did (p<0.05). CONCLUSIONS: Apoptotic activity has a characteristic time curve, reaching the highest values between the 4th and 6th hours after 30-minute intestinal ischemia. Ischemic preconditioning seemed to be protective against the morphological changes caused by intestinal ischemia-reperfusion.

OBJETIVO: Investigar a duração da apoptose causada pela isquemia-reperfusão no intestino em um novo modelo de duplo segmento de jejuno e analisar os efeitos protetores do alopurinol ou precondicionamento isquêmico (IPC). MÉTODOS: No experimento I para obter o modelo do duplo segmento de jejuno, após a laparotomia, uma parte de 30cm de comprimento de jejuno foi selecionada em cães mestiços (n=24). Anatomoses T-T foram realizadas em ambas as extremidades no meio do segmento de jejuno, criando dois segmentos iguais. Em um segmento foi induzida isquemia por oclusão dos vasos que o irrigavam e o outro segmento foi usado como controle. Amostras de tecido para detecção da apoptose foram obtidos aos 30 minutos, 1h, 2h, 4h, 6h, 8h, 12h e 24 horas de reperfusão. No experimento II usando o mesmo modelo, no tempo de reperfusão de 4 horas, foram investigados dois outros grupos (n=5 cada) usando precondicionamento com alopurinol (50 mg/kg) e IPC (3 ciclos de 5x1). RESULTADOS: No experimento I a maior atividade de apoptose detectada foi às 4h e 6h de reperfusão (14,2 ± 1,31 e 16,3 ± 1,05 no campo visual de 40x). No experimento II usando o período de 4horas de reperfusão o pré-tratamento com alopurinol aumentou a atividade apoptótica (10,72 ± 0,47) aproximadamente 2 vezes mais do que o IPC (6,72 ± 0,46) (p<0,05). CONCLUSÕES: A atividade de apoptose tem uma curva caractetística, atingindo maiores valores entre a 4ª e a 6ª horas após 30 minutos de isquemia intestinal. O precondicionamento isquêmico parece proteger contra alterações morfológicas causadas pela isquemia-reperfusão intestinal.

Effects of the ingestion of 2, 4 Dichlorophenoxyacetic acid on jejunal myenteric neurons in rats

2,4 dichlorophenoxyacetic acid (2,4-D) is a systemic herbicide. The effects of different levels of 2,4-D on some animal organ systems have been examined, but little is known about its role in the enteric nervous system. The purpose of this study was to verify the effects of 2,4-D administration on the density and morphometry of jejunal myenteric neurons in rats. Ten male rats were assigned to control (C) and experimental (E) groups. For 15 days, group E received, via gavage, 5 mg of 2,4-D.kg–1 body weight. On the 16th day, the animals were sacrificed by a lethal dose of thiopental, and the jejunum was removed by laparotomy and used to obtain whole mount preparations for Giemsa staining and NADPH-diaphorase (NADPHd+) histochemistry to identify neurons. The density and cell body area of the myenteric neurons was measured. In the total neuronal population, the neuronal density/mm2 of the jejunum in groups E and C was equivalent, and the cell body area of the rats in group E was lower (p < 0.05) than that of those in group C. For NADPHd+ neurons, the neuronal density did not differ between the groups, although the cell body area was larger (p < 0.05) in group E. It was concluded that even though 2,4-D does not alter the neuronal density in the rat jejunum, it induces cell body atrophy in the general population of neurons and hypertrophy of the NADPHd+ nitric oxide producing neurons without promoting cell death.

Efeito protetor das frações proteicas do soro de leite em camundongos Balb/C infectados por Escherichia coli O157: H7 / Protective effect of whey proteic fractions on Balb/C mice infected by Escherichia coli O157: H7

Avaliou-se o efeito protetor das frações proteicas do soro do leite sobre as vilosidades intestinais de camundongos Balb/C, fêmeas, infectadas por Escherichia coli O157:H7. Foram utilizados 48 animais, distribuídos aleatoriamente em oito grupos de seis fêmeas cada um. Os animais dos grupos 1 e 2 (controles) receberam dieta AIN93G padrão; os dos grupos 3 e 4, AIN93G + alfalactalbumina; os dos grupos 5 e 6, AIN93G + betalactoglobulina e os dos grupos 7 e 8, AIN93G + concentrado proteico total e água ad libitum por sete dias. No dia zero, os animais dos grupos 2, 4, 6 e 8 foram inoculados, por meio de cânula de gavagem, com 0,5mL de E. coli O157:H7, na concentração de 7 x 10(10)UFC/mL. Os animais foram acompanhados clinicamente e sacrificados, no oitavo dia experimental. Verificou-se, por meio de exames histológicos e da morfometria, que as frações betalactoglobulina e alfalactalbumina exerceram efeito protetor sobre as vilosidades intestinais do jejuno distal e do íleo (P<0,05), respectivamente. O concentrado proteico total não demonstrou efeito protetor sobre as vilosidades intestinais.

The protective effect of protein fractions of whey on intestinal villi of Balb/C female mice infected with Escherichia coli O157: H7 was evaluated. A total of 48 animals were randomly distributed into eight groups of six females each. Animals in groups 1 and 2 (controls) received AIN93G standard diet; the groups 3 and 4, AIN93G + alpha-lactalbumin; while groups 5 and 6, AIN93G + beta-lactoglobulin; and groups 7 and 8, AIN93G + total protein concentrate and water ad libitum for seven days. On day zero, animals of groups 2, 4, 6, and 8 were inoculated by gavage tube with 0.5mL of E. coli O157: H7 at a concentration of 7 x 10(10)CFU/mL. The animals were clinically followed and sacrificed on the eighth day. It was verified by histological examination and morphometry that the beta-lactoglobulin and alpha-lactalbumin exerted a protective effect on the villi of the distal jejunum and ileum (P<0.05), respectively. The total protein concentrate showed no protective effect on the villi.

Assessment of NADPH-diaphorase stained myenteric neurons of the jejunum of diabetic rats supplemented with ascorbic acid

The relation between hyperglycemia and diabetic neuropathy has already been demonstrated in some studies. Among the theories proposed for its etiology the oxidative stress stands out. The performance of nitric oxide as a link between the metabolic and vascular neuropathogenic factors that triggers the diabetic neuropathy has already been put forward. This study aimed to assess the quantification and measurements of the cell body profile area (CBPA) of NADPH-diaphorase reactive (NADPH-dp) myenteric neurons of the jejunum of diabetic rats (induced by streptozotocin) supplemented with Ascorbic Acid (AA). These changes in the myenteric neurons seem to be related to the gastrointestinal disturbances observed in diabetes mellitus (DM). Twenty male Wistar rats (Rattus norvegicus) were distributed in 4 groups (n=5): controls (C), control supplemented (CS), diabetic (D), and diabetic suplemented (DS). DM was induced by estreptozotocin (50mg/kg body wt). One week after the induction and confirmation of the DM (glycemia exam), animals of the groups CS and DS received 50mg of AA three times a week by gavage. After 90 days of experiment, the animals were anesthetized with lethal thiopental dose (40mg/kg) and the collected jejunum processed for the histochemistry NADPH-diaphorase technique. Whole-mount preparations were obtained for quantitative and morphometric analysis of the myenteric neurons. A quantity of jejunum neurons in the Group D (96±7.5) was not different (P>0.05) from Group DS (116±8.08), C (92±9.7), and CS (81±5.4), but in Group DS the quantity was higher (P<0.05) than in Group C and CS. The CBPA of neurons from Group D (189.50±2.68µm²) and DS (195.92±3.75µm²) were lower (P<0.05) than from Group C (225.13±4.37µm²) and CS (210.23±3.15µm²). The streptozotocin-induced DM did not change the jejunum-ileum area, the jejunum myenteric plexus space organization and the density of NADPH-dp ...

A relação entre hiperglicemia e neuropatia diabética foi demonstrada em várias pesquisas. Entre as teorias propostas para sua etiologia destaca-se o estresse oxidativo. O papel do óxido nítrico como elo entre os fatores neuropatogênicos metabólico e vascular que ativam a neuropatia diabética tem sido ressaltado. Este estudo objetivou avaliar a quantificação e a morfometria da área do perfil do corpo celular (CBPA) de neurônios mioentéricos NADPH-diaforase reativos (NADPH-dp) do jejuno de ratos diabéticos e suplementados com Ácido Ascórbico (AA), uma vez que alterações nos neurônios mioentéricos parecem estar relacionadas aos distúrbios gastrointestinais observados no diabetes mellitus (DM). Vinte ratos machos da linhagem Wistar (Rattus norvergicus) foram distribuídos em 4 grupos (n=5): controle (C), controle suplementado (CS), diabético (D) e diabético suplementado (DS). O DM foi induzido através de injeção de estreptozootocina (50mg/kg de peso corporal). Uma semana depois da indução e confirmação do DM (glicemia), animais dos grupos CS e DS receberam, via gavagem, 50mg de AA três vezes por semana. Após 90 dias de período experimental, os animais foram anestesiados com dose letal de thiopental intravenosa (40mg/kg) e o jejuno foi retirado e processado para a técnica histoquímica da NADPH-diaforase. Preparados de membrana foram obtidos para análises quantitativa e morfométrica dos neurônios mioentéricos. A quantidade de neurônios do jejuno do Grupo D (96±7,5) não diferiu (P>0,05) dos Grupos DS (116±8,08), C (92±9,7) e CS (81±5,4), mas no Grupo DS o número de neurônios foi superior (P<0,05) aos Grupos C e CS. A CBPA de neurônios do Grupo D (189,50±2,68µm²) e DS (195,92±3,75µm²) foi menor (P<0,05) do que a dos Grupos C (225,13±4,37µm²) e CS (210,23±3,15µm²). O DM induzido por estreptozootocina não alterou a área do jejuno-íleo, a organização espacial do plexo mioentérico e a densidade...

Análise morfométrica da parede intestinal do íleo de ratos submetidos a intensa carência de proteínas / Análisis morfométrica de la pared intestinal del íleo de ratas sometidos a intensacarencia de proteínas / Morphometrics analysis of the intestinal wall of the ileum of rats submitted to intensive lack of protein

Neste trabalho foram utilizados seis animais (Rattus norvegicus com 90 dias de idade) divididos em dois grupos: GC (grupo controle) e GE (grupo experimental). Os animais do GC receberam ração com teor protéico de 26% e os do GE ração com 4% de proteínas. Após 90 dias de experimento, os animais foram submetidos à eutanásia, à retirada do íleo e a processos histológicos corados por Hematoxilina e Eosina (HE), quando se avaliaram os efeitos da desnutrição protéica severa (4%) sobre ratos Wistar adultos (Rattus norvegicus) nos seguintes parâmetros: peso corporal; parede total do íleo; túnica mucosa; túnica muscular; altura do enterócito; diâmetro maior nuclear. A análise histomorfométrica da parede total do íleo dos ratos adultos desnutridos evidenciou que houve uma redução estatisticamente significante no grupo experimental em relação ao grupo controle. Ou seja: a parede intestinal alterou-se como um todo, especialmente na espessura da túnica mucosa, muscular, altura do enterócito e diâmetro maior de seu núcleo, permitindo-se concluir que a desnutrição protéica afeta tecidos de alta e baixa renovação celular presente no íleo

Six animals (Rattus norvegicus - 90 days of age) were divided into two groups: CG (Control Group) and EG (Experimental Group) were used in this study. The animals in the CG received 26%-protein chow and the EG received 4%- protein chow. 90 days later, the animals were submitted to euthanasia, remotion of their ileum for histological processes, and Hematoxylin and Eosin staining (HE). The effects of severe protein undernutrition (4%) on Wistar rats (Rattus norvegicus) regarding the following parameters were assessed: body weight, total wall thickness of the ileum, tunica mucosa, muscle tunic, enterocyte height, and higher nuclear diameter. The histomorphometric analysis of the total wall of the ileum of undernourished adult rats evidenced that there was a statistically significant reduction for the experimental group in relation to the control group. The intestinal wall suffered atrophy demonstrating that protein undernourishment affected all the tissues at the ileum

En esta investigación fueron utilizados seis animales (Rattus norvegicus con 90 días de edad) divididos en dos grupos: GC (grupo control) y GE (Grupo experimental). Los animales del GC recibieron ración con contenido proteico de 26% y los del GE ración con 4% de proteínas. Tras 90 días de experimento los animales fueron sometidos a eutanasia, remoción del íleo, procesos histológicos corados por Hematoxilina y Eosina (HE). Cuando se evaluaron los efectos de la desnutrición proteica severa (4%) sobre las ratas Wistar adultas (Rattus norvegicus) en los siguientes parámetros: peso corporal, pared total del íleo, túnica mucosa, túnica muscular, altura del enterocito y diámetro mayor nuclear. El análisis histomorfométrica de la pared total del íleo de las ratas adultas desnutridas evidenció que hubo una reducción estadísticamente significante em el grupo experimental en relación al grupo control. O sea: la pared intestinal se alteró como un todo, especialmente en La espesura de la túnica mucosa, muscular, altura del enterocito y diámetro mayor de su núcleo, permitiéndose concluir que La desnutrición proteica afecta tejidos de alta y baja renovación celular presente en el íleo

Effect of early weaning on the jejunal villi of male albino rat. Histological, histochemical and scanning electron microscopic study

Although early weaning is common in the developing countries, yet its effects on the intestinal cells development are not well established. Thirty two male albino rats were used in the current study to investigate the effects of early weaning on the jejunal villi. Animals were divided into 4 equal groups. A control group [weaned on the day 21 after birth] and three experimental groups, that were weaned on day [10], [14] and [18 days and 9 hours] after birth respectively. Animals of all groups were sacrificed on the day 22 of birth. Early weaning in the present study demonstrated necrotic areas on the surface of the villi, reduction in the villous height, vacuolation and apparent hyperplasia of the surface colummar cells which appeared to be separated from each other at many sites. There were areas of loss of the brush border of the surface columnar cells. The core of the villi showed mononuclear cellular infiltration, congested blood capillaries and edema. There was increase in the mean number of intraepithelial lymphocytes [IELs] and reduction in time mean number of goblet cells/ villas. The intensity of alkaline phosphiatase enzyme reaction was reduced. All the previous changes were markedly observed when animals were weaned at early ages. In group IV, the jejunal villi showed nearly the same appearance as that of the control group. In conclusion, early weaning resulted in harmfull effects on the jejunial villi. The only safe early weaning was observed in group IV animals that were left to suckle for 18 days amid 9 hours which equals 7/8 of the full period of suckling in rat. This coincided with what was mentioned in the holy Quran concerning human beings where the longest mentioned period of suckling was 24 months amid the shortest period was 21 months which equals 7/8 of the longest period

Morphological changes of the jejunal mucosa in protracted diarrhea and their correlation with disease duration, weight loss and serum albumin levels

The pathogenesis of protracted diarrhea is multifactorial. In developing countries, intestinal infectious processes seem to play an important role in triggering the syndrome. Thirty-four children aged 1 to 14 months, mean 6.5 months, with protracted diarrhea were studied clinically and in terms of small intestinal mucosal morphology. Mild, moderate or severe hypotrophy of the jejunal mucosa was detected in 82 percent of cases, and mucosal atrophy was observed in 12 percent. The intensity of the morphological changes of the jejunal mucosa correlated negatively with serum albumin levels. No correlation was detected between mucosal grading and duration of diarrhea or between mucosal grading and weight reported as percentile. After nutritional support was instituted, serial jejunal biopsies were obtained from 12 patients: five patients submitted to parenteral nutrition for 7 to 38 days, mean 17 days, and 7 patients reveiving a hypoallergenic oral diet (semi-elemental formula, 3; chicken formula, 3; human milk, 1). In seven cases (58 percent) a progressive increase in villus height and a decrease in the number of inflammatory cells were noted. Recovery of the morphologic pattern was accompanied by clinical improvement in all patients.

Scanning electron microscopy of the jejunum in children with protein-energy malnutrition

Samples of jejunum from seven children dying from severe oedematous malnutrition were fixed with intralumenal glutaraldehyde in combination with external immersion, using a rapid autopsy protocol. Selected areas were post-fixed in osmium tetroxide, dehydrated with an ethanol series and critical point dried. After mounting on aluminium stubs, specimens were sputter-coated with a thin layer of gold and palladium. Scanning electron microscopy showed patterns ranging from subtotal villous atrophy, through partial villous atrophy with low ridges, to longer, taller ridges with cerebriform convolutions. In one case, villous height had been interpreted as normal on light microscopy. The scanning electron microscope revealed that the mucosa in this case was composed of ridges and leaf forms. Processing for scanning electron microscopy is simple. The specimens can be viewed and photographed in a relatively short time. In addition, the three-dimensional record provides clarification of ambiguities which often arise from routine histological sections.

Yeyunoíleon

Se describe la anatomía del yeyunoileón incluyendo tamaño, desarrollo, irrigación y pliegues. De las bridas y adherencias se indican sus causas y consecuencias, las mismas constituyen hoy día la primera causa de oclusión intestinal, pero no se manifiesta hasta que no se produce la obstrucción. Su tratamiento debe ser profiláctico. Se detallan, las manifestaciones clínicas, diagnósticas y tratamiento de los tumores intestinales, vólvulos, parásitos, divérticulo de Meckel, invaginación en el adulto, enfermedad de Crohn, cuerpos extraños, lesiones traumáticas, tuberculosis intestinal, fiebre tifoidea, úlcera y divertículos

Efecto de la irradiación aguda sobre la morfometria del intestino delgado y la absorción de D-Xilosa en ratas / Effect of radiation on morphometry of small bowel and D-Xilose absorption in rats

En estudios previos en nuestro laboratorio, hemos demostrado el efecto de la radiación sobre la morfometría del intestino delgado de ratas, luego de 7 días de una única dosis abdominal externa de 10000 rad. Nuestra intención fue determinar el efecto del mismo esquema de radiación gamma, en ratas, sobre la morfometría del yeyuno y la absorción de D-Xilosa, 7, 14 y 21 días luego de la injuria, en comparación con un grupo control. La absorción de la pentosa fue medida a través de la xilosemia, 60 minutos luego de una dosis intragástrica (0,5 grs/kgr de pseo corporal) del azúcar. Resultados: En el grupo control (n: 22) el espesor de la mucosa fue de 880 ñ 40 micrones (X ñ DS), la altura vellositaria de 640 ñ 37.6 micrones y la xilosemia 15.91 ñ 11.39 mg%. Enel grupo irradiado a los 7 días (n: 11) el peso se redujo en 33.36 ñ 6.29% (vs. control p < 001), el espesor mucoso 666 ñ 97 micrones (p < 001), la altura vellositaria 466 ñ 66.9 micrones (p < 001), mientras que la xilosemia fue de 6.16 ñ 2.3 mg% (p < 05). Los valores a los 14 días (n:16) expresan una mejoría generalizada y una recuperación completa a los 21 días (n:14). En conclusión, las ratas irradiadas demostraron estar afectadas en su peso, morfometría y absorción de D-Xilosa, ésta alteración es máxima a los 7 días y se recupera completamente a los 21 días. En cambio, nosotros hemos hallado una absorción normal de D-Xilosa a los 21 días. Es de destacar que entre ese trabajo (3) y el presente existen diferencias metodológicas, lo que no los hace comparables. Hemos observado recientemente que, la correspondencia entre la absorción y las alteraciones morfométricas del yeyuno, se mantienen aún cuando se utiliza una sustancia radioprotectora como las prostaglandinas (8). Sin embargo esto no agrega luz a la discusión patogénica...

Viabilidade de alças intestinais avaliada pelo dopller-ultra-som / Viability of intestinal loops evaluated by Doppler-ultrasound

Avaliaram-se experimentalmente, através da utilizaçäo do Doppler-ultra-som, a viabilidade de alças intestinais. No 1§ tempo cirúrgico realizou-se uma desvascularizaçäo segmentar de alças de cólon e de jejuno de cäes, procedendo-se em seguida à marcaçäo do segmento isquêmico com base nas informaçöes da doplerometria. O estudo anatomopatológico das camadas muscular e mucosa das alças ressecadas 24 h após a realizaçäo do 1§ tempo revelou a validade desse método como critério para estudo da circulaçäo intestinal

Intolerancia a la lactosa y giardiasis. / Lactose intolerance and giardiasis.

Con objeto de estudiar la probable influencia de la Giardiasis en la actividad de la lactosa intestinal, se efectuó el estudio de la curva de tolerancia a la lactosa, en 54 personas portadoras de este parásito, comparándose los métodos, con un grupo control de 28 personas, libres de parasitosis. Se demostró, en el primer grupo, es decir, el portador de giardiasis, cursaron curvas planas de lactosa en 49 casos (90.8% de 54), mientras que el grupo control, este tipo de curva se detectó en 16 personas (57.2% de 28). Estos hallazgos se pudieron correlacionar con la clínica, ya que en el grupo parasitario, solo 4 de ellos (7.5% de 54, toleraban clínicamente la leche. Se considera que la diferencia hallada entre los dos grupos puede ser significativa en la influencia que pudiera tener la guiardiasis en los cuadros de intolerancia a la leche, como una causa secundaria y/u ontogenética.