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31.
We investigated the protective effect of caffeic acid phenethyl ester (CAPE) on cyclophosphamide‐induced hemorrhagic cystitis in rats in comparison with 2‐mercaptoethane sulfonate (MESNA). Forty male rats were randomized into four groups: group 1 (control), group 2 (cyclophosphamide), group 3 (cyclophosphamide + MESNA), group 4 (cyclophosphamide + CAPE). Cyclophosphamide injection increased malondialdehyde levels indicating oxidative stress, whereas CAPE and MESNA ameliorated malondialdehyde levels in the bladder (p < 0.05). Only catalase activities were decreased significantly in both groups (cyclophosphamide + MESNA and cyclophosphamide + CAPE, p < 0.05). Pretreatment with CAPE (p < 0.01) resulted in a significant decrease in nitric oxide levels when compared with the cyclophosphamide group. When we consider the studies that show the critical importance of increased nitric oxide levels in pathogenesis of cyclophosphamide‐induced hemorrhagic cystitis, we suggest that it would be more beneficial to use MESNA with CAPE to prevent histological damage.  相似文献   
32.
A potentiometric biosensor based on urease was developed for the quantitative determination of urea concentration in aqueous solutions for biomedical applications. The urease was either physisorbed onto an electrodeposited polyaniline film (PANI), or immobilized on a layer-by-layer film (LbL) assembled over the PANI film, that was obtained by the alternate deposition of charged polysaccharides (carboxymethylpullulan (CMP) and chitosan (CHI)). In the latter case, the urease (Urs) enzyme was either physically adsorbed or covalently grafted to the LbL film using carbodiimide coupling reaction. Potentiometric responses of the enzymatic biosensors were measured as a function of the urea concentration in aqueous solutions (from 10(-6) to 10(-1) mol L(-1) urea). Very high sensitivity and short response time were observed for the present biosensor. Moreover, a stability study showed a higher stability over time for the potentiometric response of the sensor with the enzyme-grafted LbL film, testifying for the protective nature of the polysaccharide coating and the interest of covalent grafting.  相似文献   
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The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. As this technology expands and improves, the ability to potentially evaluate and improve the quality of substandard lungs prior to transplant is a critical need. In order to more rigorously evaluate these approaches, a reproducible animal model needs to be established that would allow for testing of improved techniques and management of the donated lungs as well as to the lung-transplant recipient. In addition, an EVLP animal model of associated pathologies, e.g., ventilation induced lung injury (VILI), would provide a novel method to evaluate treatments for these pathologies. Here, we describe the development of a rat EVLP lung program and refinements to this method that allow for a reproducible model for future expansion. We also describe the application of this EVLP system to model VILI in rat lungs. The goal is to provide the research community with key information and “pearls of wisdom”/techniques that arose from trial and error and are critical to establishing an EVLP system that is robust and reproducible.  相似文献   
36.
The genotoxic and histopathological effects of water pollution were investigated on two fish species caught from the Buyuk Menderes River and from its tributary, the Cine Stream. The Buyuk Menderes basin is an important agricultural area in Turkey. The levels of copper, zinc, cadmium, cobalt, and lead were measured at the surface of the water and in gills, liver, and muscle tissue of Chondrostoma nasus and Barbus capito pectoralis. In some tissues, the concentrations of some of these metals exceeded acceptable levels for human consumption. Zinc was found to be the most abundant metal in water and tissues. Maximal metal accumulation was observed in the liver. To detect the genotoxic potential of contaminants, the formation of micronucleus in erythrocytes was used as indicator of chromosomal damage. The frequency of micronucleus formation did not show significant differences between locations and controls in B. capito pectoralis caught from three locations and C. nasus from two locations. The histological changes included significant decreases of the mean lengths of primary and secondary lamellae. In gills epithelia, we observed cellular proliferation that developed Because of secondary lamellae fusion, ballooning degenerations, or club deformation of secondary lamellae and cystic structures in secondary lamellae. In the liver, the changes included swollen and ruptured parenchymal cells, loss of cord structure, vacuoles filled with cellular debris, focal necrosis, and a significant increase in Kupffer cells.  相似文献   
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The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a "reemerging" disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics.  相似文献   
38.
Global reduction of DNA methylation, a part of genome reprogramming processes, occurs in a gradual manner until before implantation and is recognized as a conserved process in mammals. Here, we reported that in bovine, satellite regions exhibited varied patterns of methylation changes when one-cell egg advanced to the blastocyst; a maintenance methylation was observed in satellite I sequences, a decrease in alpha satellites, and an increase in satellite II regions. Cloned embryos exhibited similar changes for DNA methylation in the satellite I and alpha. We also observed that the satellite I and alpha sequences were methylated more in inner cell mass region of the blastocyst whereas the satellite II showed selective demethylation in this region. Together, these findings point that individual satellite sequences carry their own methylation patterns under the pressure of global demethylation, suggesting that local methylation control system acts on the satellite regions in early bovine embryos.  相似文献   
39.
This study assessed the choline status in newborns, infants, children, breast-feeding women, breast milk, infant formula, breast-fed and formula-fed infants. The serum free choline level was 35.1+/-1.1 micromol/L at birth and decreased to 24.2+/-1.6, 18.1+/-0.8, 16.3+/-0.9, 14.3+/-0.8, 12.9+/-0.6 or 10.9+/-0.6 micromol/L at 22-28, 151-180, 331-365, 571-730, 731-1095 or 4016-4380 days after birth, respectively. The serum phospholipid-bound choline level was 1997+/-75 micromol/L at birth and increased gradually to 2315+/-190 or 2572 +/-100 micromol/L at 571-730 or 4016-4380 days after birth, respectively. In breast-feeding women, serum free and phospholipid-bound choline levels were doubled at 12-28 days after birth, they decreased toward the control values with time. Free choline, phosphocholine and glycerophosphocholine were major choline compounds in breast milk. Their concentrations in mature milk were much greater than in colostrum and serum. Choline contents of breast milk varied greatly between mothers, and milk free choline levels were correlated with serum free choline (r=.541; P<.001), phospholipid-bound choline (r=.527; P<.001) and glycerophosphocholine (r=.299; P<.01) concentrations and lactating days (r=.520; P<.001). In breast-fed infants, serum free choline concentrations were correlated with free choline (r=.47; P<.001), phosphocholine (r=.345; P<.002), glycerophosphocholine (r=.311; P<.01) and total choline (r=.306; P<.01) contents of breast milk. Serum free choline concentration in formula-fed infants was lower than breast-fed infants. These data show that (a) circulating choline status is elevated during infancy and lactation, (b) choline contents of breast milk vary between mothers and milk free choline contents are influenced by maternal circulating choline status, and (c) the choline contents of breast milk can influence infants' circulating choline status.  相似文献   
40.
The uncoupling protein 2 (UCP2) is located in the inner mitochondrial membrane and downregulates the production of reactive oxygen species (ROS). Recent data suggested a role for UCP2 in the immune response. We analyzed further this hypothesis during acute Listeria monocytogenes infection in mice. Death of infected Ucp2(-/-) mice was delayed in comparison with Ucp2(+/+), suggesting a role of UCP2 in the early step of the immune response. In vitro, the higher resistance of Ucp2(-/-) mice was not associated with a better control of bacterial growth by macrophages. In vivo, a significant increase of recruited phagocytes was observed in the spleen of Ucp2(-/-) mice. This was associated with a higher level of ROS in the spleen. Upregulation of pro-inflammatory cytokines IFNgamma, IL6, and IL1beta and of the chemokine MCP1 was observed in Ucp2(-/-) mice 4 days after infection, preceded by a decrease of the anti-inflammatory cytokine IL10 production. Present data highlight that, in an acute model of infection, UCP2 modulates innate immunity, via the modulation of ROS production, cytokine and chemokine production and consequently phagocyte recruitment.  相似文献   
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