Antiulcerogenic Activity of the Essential Oil of Baccharis dracunculifolia on Different Experimental Models in Rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The early systemic and gastrointestinal oxygenation effects of hemorrhagic shock resuscitation with hypertonic saline and hypertonic saline 6% dextran-70: A comparative study in dogs

The smaller volemic state from hypertonic (7.5%) saline (HS) solution administration in hemorrhagic shock can determine lesser systemic oxygen delivery and tissue oxygenation than conventional plasma expanders. In a model of hemorrhagic shock in dogs, we studied the systemic and gastrointestinal oxygenation effects of HS and hyperoncotic (6%) dextran-70 in combination with HS (HSD) solutions in comparison with lactated Ringer's (LR) and (6%) hydroxyethyl starch (HES) solutions. Forty-eight mongrel dogs were anesthetized, mechanically ventilated, and subjected to splenectomy. A gastric air tonometer was placed. in the stomach for intramucosal gastric CO2 (Pgco(2)) determination and for the calculation of intramucosal. pH (pHi):[pHi = pHa - log(Pgco(2)/Paco(2))].The dogs were hemorrhaged (42% of blood volume) to hold mean arterial blood pressure at 40-50 mm Hg over 30 min and were then resuscitated with LR (n = 12) in a 3:1 relation to removed blood volume; HS (n = 12), 6 mL / kg; HSD (n = 12), 6 mL / kg; and HES (mean molecular weight, 200 kDa; degree of substitution, 0.5) (n = 12) in a 1:1 relation to the removed blood volume. Hemodynamic, systemic, and gastric oxygenation variables were measured at baseline, after 30 min of hemorrhage, and 5, 60, and 120 min after intravascular fluid resuscitation. After fluid resuscitation, HS showed significantly lower arterial pH and mixed venous Po-2 and higher systemic oxygen uptake index and systemic oxygenation extraction than LR and HES (P < 0.05), whereas HSD showed significantly lower arterial pH than LR and HES (P < 0.05). Only HS and HSD did not return arterial pH and pHi to control levels (P < 0.05). In conclusion, all solutions improved systemic and gastrointestinal oxygenation after hemorrhagic shock in dogs. However, the HS solution showed the worst response in comparison to LR and HES solutions in relation to systemic oxygenation, whereas HSD showed intermediate values. HS and HSD solutions did not return regional oxygenation to control values.

Esophagectomy and substitution of the thoracic esophagus in dogs

OBJETIVO: Avaliar, em cadáveres de cães, uma técnica para remoção do esôfago torácico sem toracotomia e dois métodos de substituição do esôfago torácico. MÉTODOS: Foram utilizados 27 cadáveres de cães. Estes foram aleatoriamente divididos em três grupos de nove animais, em que se estudou: G1 - esofagectomia torácica total pelo método de invaginação retrógrada; G2 - esofagectomia torácica total com substituição esofágica pelo estômago inteiro; G3 - esofagectomia torácica total com substituição esofágica por um gastrotubo confeccionado de acordo com a técnica de Büchler de gastroplastia por rotação do fundo. Após a ressecção esofágica no grupo 1, a integridade da rota intratorácica foi avaliada por endoscopia e solução de azul de metileno a 1%. RESULTADOS: A ruptura da pleura visceral ocorreu em todos os animais, especialmente no terço caudal. Entretanto, a rota transtorácica mediastinal permitiu a elevação de ambos os substitutos esofágicos (G2 e G3) para a realização da anastomose com a extremidade caudal do esôfago cervical. CONCLUSÕES: A substituição por estômago inteiro apresentou menor tensão na anastomose, maior facilidade e rapidez comparada à técnica de gastroplastia por rotação do fundo. Os resultados em cadáveres suportam a realização de estudos clínicos para validação da técnica.

Gastric mucosal perfusion in dogs: Effects of halogenated anesthetics and of hemorrhage

The gastrointestinal tract is one of the first organs affected by hypoperfusion during hemorrhagic shock. The hemodynamics and oxygen transport variables during hemorrhagic shock and resuscitation can be affected by the anesthetics used. In a model of pressure-guided hemorrhagic shock in dogs, we studied the effects of three halogenated anesthetics - halothane, sevoflurane, and isoflurane - at equipotent concentrations on gastric oxygenation. Thirty dogs were anesthetized with 1.0 minimum alveolar anesthetic concentration (MAC) of either halothane, sevoflurane, or isoflurane. A gastric tonometer was placed in the stomach to determine mucosal gastric CO2 (PgCO(2)) and for the calculation of gastric-arterial PCO2 gradient (PCO2 gap). The dogs were splenectomized and hemorrhaged to hold mean arterial pressure at 40-50 mm Hg over 45 min and then resuscitated with the shed blood volume. Hemodynamics, systemic oxygenation, and PCO2 gap were measured at baseline, after 45 min of hemorrhage, and at 15 and 60 min after blood resuscitation. Hemorrhage induced reductions of mean arterial pressure and cardiac index, while systemic oxygen extraction increased (p < .05), without significant differences among groups (p > .05). Halothane group showed significant lower PCO2 gap values than the other groups (p < .05). After 60 min of shed blood replacement, all groups restored hemodynamics, systemic oxygenation, and PCO2 gap to the prehemorrhage levels (p > .05), without significant differences among groups (p > .05). We conclude that halothane is superior to preserve the gastric mucosal perfusion in comparison to isoflurane and sevoflurane, in dogs submitted to pressure-guided hemorrhagic shock at equipotent doses of halogenated anesthetics.

Anestesia subaracnóidea em crianças

JUSTIFICATIVA E OBJETIVOS: Tem aumentado muito o emprego da anestesia subaracnóidea em crianças, principalmente neonatos com risco de desenvolver apnéia neonatal. O objetivo deste trabalho foi rever as diferenças anatômicas, fisiológicas e farmacológicas desta técnica em crianças. CONTEÚDO: A anestesia subaracnóidea em crianças, apesar de ter sido técnica empregada desde o início do século XX, teve sua popularidade diminuída com o advento dos anestésicos inalatórios e bloqueadores neuromusculares, para ser novamente resgatada em 1979. As características favoráveis desta técnica em pediatria são relativas à estabilidade cardiovascular, em crianças de até 8 anos de idade, à analgesia satisfatória e ao relaxamento muscular. Os anestésicos mais utilizados em crianças são a tetracaína e a bupivacaína, cujas doses são ajustadas tomando-se por base o peso corporal. Esta técnica é limitada pela duração relativamente curta, devendo ser utilizada para procedimentos cirúrgicos que não ultrapassem 90 minutos e também pela analgesia não abranger o pós-operatório. As complicações são as mesmas encontradas no paciente adulto, incluindo cefaléia por punção dural e irritação radicular transitória. As indicações são várias: cirurgias de abdômen inferior, genitália, membros inferiores, região perineal e, em alguns casos, até em cirurgias torácicas. Seu emprego tem particular interesse nos recém-nascidos prematuros, pelo risco de apresentarem a apnéia da prematuridade. CONCLUSÕES: A anestesia subaracnóidea em crianças é técnica relativamente segura, com poucas complicações e pode ser considerada como opção para anestesia geral, principalmente nos recém-nascidos prematuros com risco de apresentarem complicações respiratórias no pós-operatório.

Carcinogenesis of the upper gastrointestinal tract induced by N-methyl-N '-nitro-nitrosoguanidine and reflux of duodenal contents in the rat

Purpose: To investigate the combined effects of reflux of duodenal contents through the pylorus and treatment with N-methyl-N'-nitro-nitrosoguanidine ( MNNG) on the development of lesions in the glandular stomach, at the gastrojejunal anastomosis and in the forestomach of rats. Methods: Eighty Male Wistar rats were divided into 4 groups: G1: MNNG + Reflux, G2: Reflux, G3: MNNG and G4: Gastrostomy. MNNG was given in the drinking water ( 100 mg/ml) for 12 weeks and then two groups ( G1 and G2) were submitted to a gastrojejunal anastomosis followed by section of the afferent loop and suture of both stumps to allow reflux of duodenal contents through the pylorus. The animals were sacrificed 18 and 36 weeks after surgery. The lesions obtained in the antral mucosa, at the gastrojejunal anastomosis and in the forestomach were analysed histologically. Results: Duodenal reflux induced proliferative lesions at both glandular and squamous mucosa of the stomach. In the antrum, adenomatous hyperplasia (AH) was observed in 20% and 50% of the animals at the 18(th) and 36(th) weeks respectively. Aditionally 85% of the animals presented AH at the gastrojejunal anastomosis and 60% developed squamous hyperplasia at the squamous portion of the stomach. MNNG treatment plus duodenal reflux enhanced the development of malignant tumors at both glandular and squamous mucosa, since there were 30% of antral adenocarcinomas and 45% of squamous carcinomas at the 18th week and the frequency of these malignant tumors rose to 50% in the antrum and 65% in the squamous mucosa at the 36th week. Conclusion: The reflux of duodenal contents through the pylorus enhanced the development of proliferative lesions, benign and malignant, in the glandular stomach and in the forestomach of rats.

Infecção por Helicobacter pylori e câncer gástrico: freqüência de cepas patogênicas cagA e vacA em pacientes com câncer gástrico

INTRODUÇÃO: Apesar da alta freqüência de infecção por Helicobacter pylori na população, somente uma minoria de indivíduos desenvolve câncer gástrico. É provável que a colonização da mucosa por cepas patogênicas, levando a maior agressão e inflamação da mucosa seja um dos elos da cadeia de eventos da oncogênese gástrica. OBJETIVOS: Investigar a freqüência de cepas patogênicas cagA e vacA do H. pylori em pacientes com câncer gástrico. MATERIAL E MÉTODOS: Foram estudados retrospectivamente 42 pacientes com câncer gástrico. A infecção por H. pylori foi avaliada por exame histológico e pelo PCR para identificação dos genótipos cagA e vacA em amostras de material fixado em formalina e incluído em parafina. RESULTADOS: A análise histológica permitiu a visualização direta do H. pylori em 85,7% dos casos, e o método de PCR para o gene urease C demonstrou a presença de DNA da bactéria em 95% dos casos. O gene cagA foi detectado em amostras de 23 pacientes (54,7%) com câncer gástrico. O alelo s1 do gene vacA foi identificado em amostras de 24 pacientes (57,1%) e o alelo m1, em amostras de 26 pacientes (61,9%). Os alelos s1 e m1 foram identificados simultaneamente em 24 pacientes (57,1%). O alelo s2 foi identificado em amostras de quatro pacientes (9,5%), e o alelo m2, em amostras de três pacientes (7,1%). A freqüência de infecção pelo Helicobacter pylori foi similar em ambos os tipos histológicos de câncer gástrico (intestinal e difuso). CONCLUSÕES: Os resultados confirmam a relevância dos genótipos patogênicos cagA e vacA do H. pylori para lesões orgânicas significativas tais como o câncer gástrico, sugerindo a participação dessa bactéria na cadeia de eventos da oncogênese gástrica.

Scintigraphic validation of AC Biosusceptometry to study the gastric motor activity and the intragastric distribution of food in humans

Abnormal intragastric distribution of food (IDF) and a phasic contractility in the proximal stomach have been related to dyspeptic symptoms. Thus, the behaviour of the stomach and the proximal region, in particular, continues to attract attention and demand for reliable and comfortable techniques. The aims of this study were to employ AC Biosus-ceptometry (ACB) and scintigraphy to evaluate IDF and gastric motor activity in humans. Fifteen healthy volunteers ingested 60 mL of yogurt containing 2 mCi of Tc-99m and 4 g of ferrite. Each volunteer had gastric motility and IDF evaluated twice on separate days; on one occasion by ACB and another by scintigraphy. Digital signal processing was performed in MatLab (Mathworks Inc., Natick, MA, USA). Results were expressed as mean +/- SD. Similar results of distal accumulation time (P < 0.001) were obtained for scintigraphy (6.93 +/- 3.25 min) and for ACB (7.04 +/- 3.65 min). Fast Fourier Transform revealed two dominant frequencies (P > 0.9). Besides the well-know frequency of 3 cpm, our results showed identical frequencies in proximal stomach recordings (P < 0.001) for scintigraphic (1.01 +/- 0.01 cpm) and ACB (0.98 +/- 0.06 cpm). In summary, our data showed that scintigraphy and ACB are promising techniques to evaluate several aspects of gastric motility. Moreover, ACB is non-invasive, radiation-free and deserves the same importance as conventional methods for this kind of analysis.

Rotura gástrica por barotrauma

Barogenic rupture of the stomach is a rare complication following cardiopulmonary resuscitation, administration of nasal oxygen by catheter and diving accidents. We report a case of gastric barotrauma following oroesophageal intubation. In most cases, the tears occur along the lesser curvature, what have been already attributed to Laplace's formula and, more recently, to morphological features of the stomach.

Dimensional analysis of burden in family caregivers of patients with obsessive-compulsive disorder

Aims: Obsessivecompulsive disorder (OCD) also generates emotional burden in the patient's family members, but no study has evaluated the specific dimensions of burden. The objectives were to evaluate the dimensions of the Zarit Burden Interview (ZBI) and possible correlates. Methods: This was a cross-sectional study involving 47 patients and 47 caregivers, using a sociodemographic questionnaire; the ZBI; the Self Reporting Questionnaire; the Family Accommodation Scale; and the YaleBrown ObsessiveCompulsive Scale. The ZBI factor analysis was conducted using Varimax Rotation. Results: Six factors were identified, explaining 74.2% of the total variance: factor 1, interference in the caregiver's personal life (36.6% of the variance); factor 2, perception of patient's dependence (10.8%); factor 3, feelings of irritation or intolerance (9.2%); factor 4, guilt (7.2%); factor 5, insecurity (5.6%); and factor 6, embarrassment (4.8%). The six ZBI factors were associated with greater OCD severity and with greater accommodation to the patient's symptoms, and factors 1, 2, 5 and 6 with caregiver's psychological morbidity. Caregiver's sex (female) was associated with factors 5 and 6, relationship with the patient (being a parent or son/daughter) with factor 5, higher educational level with factor 6, living with the patient with factor 3, worse self-evaluation of health with factors 1, 5 and 6, and occupational status (not working) with factors 1, 2, 5 and 6. Conclusion: The dimensions of burden identified indicate the most affected aspects of a caregiver's life and could guide the planning of more specific interventions. Thus, the caregiver could participate more effectively in the OCD patient's treatment, with a lower impact on his/her life.

Métodos para abandono do tabagismo e tratamento da dependência da nicotina

O tabagismo está relacionado a 30% das mortes por câncer. É fator de risco para desenvolver carcinomas do aparelho respiratório, esôfago, estômago, pâncreas, cérvix uterina, rim e bexiga. A nicotina induz tolerância e dependência pela ação nas vias dopaminérgicas centrais, levando às sensações de prazer e recompensa mediadas pelo sistema límbico. É estimulante do sistema nervoso central (SNC), aumenta o estado de alerta e reduz o apetite. A diminuição de 50% no consumo da nicotina pode desencadear sintomas de abstinência nos indivíduos dependentes: ansiedade, irritabilidade, distúrbios do sono, aumento do apetite, alterações cognitivas e fissura pelo cigarro. O aconselhamento médico é fundamental para o sucesso no abandono do fumo. A farmacoterapia da dependência de nicotina divide-se em: primeira linha (bupropiona e terapia de reposição da nicotina), e segunda linha (clonidina e nortriptilina). A bupropiona é um antidepressivo não-tricíclico que age inibindo a recaptação de dopamina, cujas contra-indicações são: epilepsia, distúrbios alimentares, hipertensão arterial não-controlada, abstinência recente do álcool e uso de inibidores da monoaminoxidase (MAO). A terapia de reposição de nicotina pode ser feita com adesivos e gomas de mascar. Os efeitos da acupuntura no abandono do fumo ainda não estão completamente esclarecidos. As estratégias de interrupção abrupta ou redução gradual do fumo têm a mesma probabilidade de sucesso.

Effects of uracil calculi on cell growth and apoptosis in the BBN-initiated Wistar rat urinary bladder mucosa

The different potential of initiated and non-initiated urinary bladder mucosa (UBM) to develop neoplasia was quantitatively evaluated in the male Wistar rat. Initiation of carcinogenesis was accomplished with N-butyl-N- (4-hydroxybutyl) -nitrosamine (BBN). Stimuli for cell proliferation and apoptosis were obtained by exposure followed by withdrawal of 3% Uracil in the diet. The proliferation index (PI) was estimated in UBM immunostained for the proliferating nuclear cell antigen (PCNA). The apoptotic index (AI) and the density of papillary/nodular hyperplasia (PNH) were estimated in hematoxilin-eosin stained sections. PNH was the main proliferative response to the mechanical irritation by uracil, irrespective of previous initiation with BBN. Uracil exposure induced higher PI and PNH density in the initiated rats. After uracil withdrawal, there was a significant increase of the AI in both uracil-treated groups, which correlated well to the respective PNH density. However, at the end of the experiment, PNH incidence and density were significantly higher in the BBN-initiated mucosa, which also presented 18% incidence of papillomas and 27% of carcinomas. Therefore, under prolonged uracil calculi trauma, the UBM of BBN-initiated Wistar rats gives rise to epithelial proliferative lesions that progress to neoplasia through acquired resistance to apoptosis. (C) 1999 Wiley-Liss, Inc.

CDX2, a highly sensitive and specific marker of adenocarcinomas of intestinal origin - An immunohistochemical survey of 476 primary and metastatic carcinomas

CDX2 is a recently cloned homeobox gene that encodes an intestine-specific transcription factor, expressed in the nuclei of epithelial cells throughout the intestine, from duodenum to rectum. While expression of CDX2 protein in primary and metastatic colorectal carcinomas has been previously documented, neither the sensitivity nor the specificity of CDX2 expression, as determined by immunohistochemistry, for colorectal adenocarcinoma has been determined. We performed an immunohistochemical survey of 476 tumors with a monoclonal antibody, CDX2-88, including 89 tumors from the colon and duodenum and 95 tumors from other gastrointestinal sites, including the esophagus, stomach, pancreatobiliary system, gastrointestinal carcinoids, and liver. CDX2 was expressed uniformly (that is, in 76-100% of tumor cells) in all but one of the evaluated colorectal and duodenal tumors. High-level expression of CDX2 was also found, however, in mucinous ovarian carcinomas and adenocarcinomas primary to the urinary bladder of which 64% and 100% were positive, respectively. Gastric, gastroesophageal, and pancreatic adenocarcinomas and cholangiocarcinomas all showed similar, heterogeneous patterns of CDX2 expression. Most tumors in each group showed CDX2 expression by a minority of cells, whereas a substantial minority of cases in each group was completely negative and a smaller minority was uniformly positive. Gastrointestinal carcinoids gave similarly varied results, but the majority (58%) was negative. Hepatocellular carcinomas showed no expression of CDX2. Only very rare examples of carcinomas of the genitourinary and gynecologic tracts, breast, lung, and head and neck showed significant levels of CDX2 expression. In this study of primary and metastatic epithelial tumors, uniform CDX2 expression is demonstrated to be an exquisitely sensitive and highly, but incompletely, specific marker of intestinal adenocarcinomas. Compared with villin, a previously described marker of GI adenocarcinomas, CDX2 demonstrated superior sensitivity and comparable specificity. CDX2 expression can be seen, however, in selected non-GI adenocarcinomas such as mucinous ovarian carcinomas and adenocarcinomas of the urinary bladder.

Ectopic ossification presenting as osteoid metaplasia in a salivary mucocele in a Shih Tzu dog

Background: Salivary mucocele is an accumulation of saliva in a single or multiloculated cavity lined by connective tissue that is contiguous to a salivary gland-duct complex and is the most common condition affecting the salivary glands in dogs. Occasionally, different types of metaplastic lesions, such as squamous and osseous metaplasia - which are rare lesions in animals - can be observed in association with salivary mucocele.Case presentation: A right facial enlargement was suddenly observed in a 4-year-old non-spayed female Shih-Tzu dog. The lesion presented itself as a soft and fluctuant mass located in the right side of the face near to the neck. Histologically, the mass consisted of a cavitary formation without an epithelial lining. Additionally, microscopic examination revealed the presence of osteoid-producing cells which gave rise to areas of bone formation, probably induced by irritation due to the presence sialoliths. Such cells and bone formations were also present in the cavity wall, consequently leading us to classify the condition as a salivary mucocele with osseous metaplasia.Conclusions: In the present case, the pathogenesis was probably associated with the presence of sialoliths, which can behave as etiological agents for the metaplastic lesion. The occurrence of osteoid metaplasia is a rare peculiar condition in the canine salivar y gland, and due to the rarity and lack of information about this specific disease, no clinical data can yet be associated with the development of salivary mucocele with osseous metaplasia in dogs.

Immunohistochemical and morphological features of a small bowel leiomyoma in a black crested macaque (Macaca nigra)

Background: Spontaneous gastrointestinal neoplasms in non-human primates are commonly seen in aged individuals. Due to genetic similarities between human and non-human primates, scientists have shown increasing interest in terms of comparative oncology studies.Case presentation: The present study is related to a case of an intestinal leiomyoma in a black crested macaque (Macaca nigra), kept on captivity by Mateca a Zoo, Pereira City, Colombia. The animal had abdominal distension, anorexia, vomiting, diarrhea and behavioral changes. Clinical examination showed an increased volume in the upper right abdominal quadrant caused by a neoplastic mass. The patient died during the surgical procedure. Necropsy revealed several small nodules in the peritoneum with adhesion to different portions of the small and large intestines, liver, stomach and diaphragm. Tissue samples were collected, routinely processed and stained by H&E. Microscopic examination revealed a mesenchymal tumor limited to tunica muscularis, resembling normal smooth muscle cells. Neoplastic cells were positive for alpha-smooth muscle actin and vimentin, and negative for cytokeratin AE1/AE3 by immunohistochemistry. Those morphological and immunohistochemical findings allowed to diagnose the intestinal leiomyoma referred above.Conclusion: Neoplastic diseases in primates have multifaceted causes. Their manifestations are understudied, leading to a greater difficulty in detection and measurement of the real impact provides by this disease.