The role of IFN-gamma and IL-4 in gastric mucosa inflammation associated with Helicobacter heilmannii type 1 infection

Although Helicobacter heilmannii infection is less common than H. pylori infection in humans, it is considered to be of medical importance because of its association with gastritis, gastric ulcer, carcinoma, and mucosa-associated lymphoid tissue lymphoma of the stomach. However, there have been no studies evaluating the role of the Th cell response in H. heilmannii gastric infection. We evaluated the participation of pro-inflammatory and anti-inflammatory cytokines, IFN-gamma and IL-4, in H. heilmannii gastric infection in genetically IFN-gamma- or IL-4-deficient mice. The serum IFN-gamma and IL-4 concentrations were determined by ELISA. The gastric polymorphonuclear infiltrate was higher (P = 0.007) in H. heilmannii-positive than in H. heilmannii-negative wild-type (WT) C57BL/6 mice, whereas no significant inflammation was demonstrable in the stomach of H. heilmannii-positive IFN-gamma-/- C57BL/6 mice. The degree of gastric inflammatory cells, especially in oxyntic mucosa, was also higher (P = 0.007) in infected IL-4-/- than in WT BALB/c mice. Serum IFN-gamma levels were significantly higher in IL-4-/- than in WT BALB/c mice, independently of H. heilmannii-positive or -negative status. Although no difference in serum IFN-gamma levels was seen between H. heilmannii-positive (11.3 ± 3.07 pg/mL, mean ± SD) and -negative (11.07 ± 3.5 pg/mL) WT BALB/c mice, in the group of IL-4-/- animals, the serum concentration of IFN-g was significantly higher in the infected ones (38.16 ± 10.5 pg/mL, P = 0.04). In contrast, serum IL-4 levels were significantly decreased in H. heilmannii-positive (N = 10) WT BALB/c animals compared to the negative (N = 10) animals. In conclusion, H. heilmannii infection induces a predominantly Th1 immune response, with IFN-gamma playing a central role in gastric inflammation.

Quantification of fecal estradiol and progesterone metabolites in Syrian hamsters (Mesocricetus auratus)

Alternative methods to the utilization of laboratory animal blood and its by-products are particularly attractive, especially regarding hamsters due to their small size and difficulties in obtaining serial blood samples. Steroid hormone metabolite quantification in feces, widely used in studies of free-ranging or intractable animals, is a non-invasive, non-stressor, economical, and animal saving technique which allows longitudinal studies by permitting frequent sampling of the same individual. The present study was undertaken to determine the suitability of this method for laboratory animals. Estradiol and progesterone metabolites were quantified by radioimmunoassay in feces of intact, sexually mature female Syrian hamsters during the estrous cycle (control) and in feces of superovulated females. Metabolites were extracted by fecal dilution in ethanol and quantified by solid phase radioimmunoassay. Median estrogen and progesterone concentrations were 9.703 and 180.74 ng/g feces in the control group, respectively. Peaks of estrogen (22.44 ± 4.54 ng/g feces) and progesterone (655.95 ± 129.93 ng/g feces) mean fecal concentrations respectively occurred 12 h before and immediately after ovulation, which is easily detected in this species by observation of a characteristic vaginal postovulatory discharge. Median estrogen and progesterone concentrations (28.159 and 586.57 ng/g feces, respectively) were significantly higher in superovulated animal feces (P < 0.0001). The present study demonstrated that it is possible to monitor ovarian activity in Syrian hamsters non-invasively by measuring fecal estradiol and progesterone metabolites. This technique appears to be a quite encouraging method for the development of new endocrinologic studies on laboratory animals.

Estudo retrospectivo sobre o uso de dipiradamol e ácido acetil-salicílico no pré, trans e pós-operatório, na prevençäo de complicaçöes trombembólicas, em cirurgia vascular de alto risco / The use of dipyridamole and acetylsalicylic acid in pre, trans and post-operative periods, in the prevention of thromboembolic complications, in vascular surgery of high risk

Num estudo retrospectivo avaliou-se os resultados de três diferentes esquemas de terapêutica antiplaquetária, na prevençäo de complicaçöes trombembólicas a curto e a longo prazo, usadas nos últimos 10 anos no Serviço de Cirurgia Vascular do Hospital Universitário da Universidade Federal de Santa Maria, envolvendo um total de 645 pacientes. Os pacientes, de ambos os sexos, foram divididos em quatro grupos: I) controle; II) dipiridamol 75 mg 3 vezes ao dia e ácido acetilsalicílico (AAS) 500 mg 2 vezes ao dia; III) dipiridamol 75 mg 3 vezes ao dia e AAS 250 mg 2 vezes ao dia; IV) dipiridamol 75 mg 3 vezes ao dia e AAS 100 mg 3 vezes ao dia. Todos os pacientes receberam heparina trans e pós-operatória. Nos grupos, II III e IV foi também empregado dipiridamol no pré e trans-operatório. A incidência de trombembolismo, retrombose, flebite, embolia pulmonar e reoclusäo vascular foi reduzida de modo significativo nos pacientes tratados com a associaçäo dipiridamol + AAS quando comparados aos näo-tratados, todos submetidos à cirurgia vascular. Os pacientes do grupo IV apresentaram os menores índices de efeitos colaterais