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71.
Coffee consumption is worldwide spread with few side effects. Interestingly, coffee intake has been inversely related to the serum enzyme activities gamma-glutamyltransferase, and alanine aminotransferase in studies performed in various countries. In addition, epidemiological results, taken together, indicate that coffee consumption is inversely related with hepatic cirrhosis; however, they cannot demonstrate a causative role of coffee with prevention of liver injury. Animal models and cell culture studies indicate that kahweol, diterpenes and cafestol (some coffee compounds) can function as blocking agents by modulating multiple enzymes involved in carcinogenic detoxification; these molecules also alter the xenotoxic metabolism by inducing the enzymes glutathione-S-transferase and inhibiting N-acetyltransferase. Drinking coffee has been associated with reduced risk of hepatic injury and cirrhosis, a major pathogenic step in the process of hepatocarcinogenesis, thus, the benefit that produces coffee consumption on hepatic cancer may be attributed to its inverse relation with cirrhosis, although allowance for clinical history of cirrhosis did not completely account for the inverse association. Therefore, it seems to be a continuum of the beneficial effect of coffee consumption on liver enzymes, cirrhosis and hepatocellular carcinoma. At present, it seems reasonable to propose experiments with animal models of liver damage and to test the effect of coffee, and/or isolated compounds of this beverage, not only to evaluate the possible causative role of coffee but also its action mechanism. Clinical prospective double blind studies are also needed.  相似文献   
72.
Effects of the complete replacement of fish meal (FM) by soy protein concentrate (SPC) in high-energy diets (23 MJ kg− 1 gross energy) on intestinal and liver histology were investigated in rainbow trout (Oncorhynchus mykiss). We developed a novel morphometric method to quantify the changes at the macro- and micromorphology level. Fish were acclimatized to the diet for 90 d and were then fed 1.0 g kg BW− 1 d− 1 once per day for 14 d before 10 fish per diet were randomly sampled, 6 h after their last meal. Fold height, epithelium length, stroma proportion of the proximal and distal intestines were not affected by the diet. No significant diet effect was detected on the features of the valve in the distal intestine. Fold height was linked to epithelium length in the proximal and distal intestines and this relationship was not modified by FM replacement. Enterocyte height and width were lower in SPC-fed fish in the distal intestine, but in the proximal intestine their morphology was not affected by the diet. There was no diet effect on the number of cells infiltered between the enterocytes in the proximal and distal intestines. The enterocyte nucleus was closer to the apex in the proximal and distal intestines in SPC-fed fish, but the features of the nucleus were not affected by the diet. The mean hepatocyte volume was on an average 36% lower in SPC-fed fish and was positively correlated to the hepatosomatic index for fish fed this diet only. In conclusion, SPC used in the present study did not either cause inflammatory reaction of the gut nor affected the epithelium surface. We suggest that the modifications due to SPC are linked to variations in the metabolic status of the enterocyte.  相似文献   
73.
The fatty acid (FA) and dimethylacetal profiles of the sn-1 and sn-2 positions of different phospholipid (PL) classes from skeletal muscle of rats as affected by dietary FA profiles were studied. Rats were fed either a control diet, an olive oil-enriched diet, or a sunflower oil-enriched diet. The FA composition of both positions of the studied PL classes was affected by diet to different extents. The FA composition of the sn-2 position of phosphatidylserine was the most influenced by diet, while phosphatidylinositol was less affected by dietary modification. The FA profile of phosphatidylcholine reflected consumed FA better than any other studied PL. Thus, olive oil rats showed higher oleic acid (C18:1 n-9) contents in both positions of phosphatidylcholine, and sunflower oil rats had higher proportions of arachidonic acid (C20:4 n-6) in the sn-1 position of this PL class. Dimethylacetals were scarcely affected by diet, and only the dimethylacetal composition of phosphatidylethanolamine showed significant modifications.  相似文献   
74.
A continuous monitoring of spatial and temporal variability of soil water content was studied under two soil management systems: direct drilling (DD) and conventional tillage (CT), during four consecutive seasons. The soil water content was read at different soil depths using multisensor capacitance probes in each soil-management treatment. During the first season (2003–2004), soil water content dynamics for both treatments were similar during the rainy season, although the DD plot was able to retain more water in the soil profile, and during the maximum evapotranspirative period faster soil water depletion took place in the CT plot. The 2004–2005 season registered a high evapotranspiration rate (1741 mm) with low rainfall (228 mm), promoting a low soil water recharge for both treatments. The 2005–2006 season registered an increase in rainfall, promoting a greater recovery of the soil water reserve in DD than CC plot. Finally, during the 2006–2007 season with an evapotranspiration rate ET0 and rainfall of 1504 and 560 mm, respectively, DD retained more soil water content, mainly in the deeper zones, with progressive soil water depletion during the maximum evapotranspirative period in comparison to CT. Thus, DD was demonstrated to be a promising soil management technique for improving the soil water content.  相似文献   
75.
Landscape Ecology - Linking spatial pattern and process is a difficult task in landscape ecology because spatial patterns of populations result from complex factors such as individual traits, the...  相似文献   
76.
The occurrence of the fox tapeworm Echinococcus multilocularis in Red foxes was studied in Belgium and a neighbouring region in The Netherlands. A total number of 1202 foxes were analysed (1018 in Belgium and 184 in The Netherlands) of which 179 were infected with E. multilocularis (164 in Belgium and 15 in The Netherlands). Further, the spatial distribution of infection among sampled foxes was analysed with an ellipsoidal gradient, demonstrating a decreasing prevalence in northwestern direction. Using this gradient, we showed that the spatial patterns of infection in Belgium and the neighbouring region in The Netherlands correspond, indicating a continuous distribution of E. multilocularis across the nation borders. Part of the Belgian data allowed investigating temporal changes in the spatial distribution of E. multilocularis. This revealed a northwestern spread of E. multilocularis.  相似文献   
77.
Ticks are known or suspected vectors for a wide range of bacterial pathogens. One of the first steps for tick-borne risk assessment is the detection of these pathogens in their vectors. In the present study, a broad-range PCR amplification of the eubacterial gene encoding the 16S rRNA gene combined with Temporal Temperature Gradient gel Electrophoresis (TTGE) was evaluated as a method allowing the one-step detection of bacterial pathogen DNA in ticks. Firstly, DNA extracts from bacteria known to be tick-borne pathogens, i.e., Borrelia burgdorferi lato sensu, Anaplasma phagocytophilum, Spotted Fever Group (SFG) Rickettsia spp., were used to establish a TTGE pathogen DNA reference marker. Secondly, we used broad-range PCR-TTGE to detect the presence of DNA from these three pathogens in 55 DNA extracts from pools of 10 nymphal Ixodes ricinus ticks, which have been previously shown to carry DNA from at least one of those bacteria by specific PCR. Among the 20 B. burgdorferi specific-PCR samples, 15 (75%) were also found to be positive using PCR-TTGE. Sixteen of the seventeen (94%) Rickettsia spp. PCR-specific samples were positive using PCR-TTGE detection and all PCR-specific positive extracts (11/11, 100%) for A. phagocytophilum were also positive using PCR-TTGE. Moreover, we identified unexpected bacterial sequences that were not related to any of the three pathogens such as a sequence related to Spiroplasma sp. Thus, broad-range PCR-TTGE allowed the single step detection of DNA from up to 3 pathogens in the same co-infected samples as well as detection of DNA from unexpected bacteria.  相似文献   
78.
79.
A marine-derived strain of Clonostachys rosea isolated from sediments of the river Loire estuary (France) was investigated for its high lipid production. The fungal strain was grown on six different culture media to explore lipid production changes. An original branched conjugated fatty acid, mainly present in triglycerides and mostly produced when grown on DCA (23% of total fatty acid composition). It was identified as 4-Me-6E,8E-hexadecadienoic on the basis of spectroscopic analyses. This fatty acid reduced viability of MCF-7 breast cancer cells in a dose dependent manner (up to 63%) at physiological free fatty acid human plasma concentration (100 μM). Reduction of gene expression of two lipogenic enzymes, the acetyl CoA carboxylase (ACC) and the fatty acid synthase (FAS) was evaluated to explore the mechanisms of action of 4-Me-6E,8E-16:2 acid. At 50 μM, 50% and 35% of mRNA gene expression inhibition were observed for ACC and FAS, respectively.  相似文献   
80.
We studied the influence of Imipenem and Cefmetazol (50 mg/l) on lymphocyte receptors CD2, Fc and C3b of complement. The lymphocytes were obtained from human blood and mice axillary ganglions. Cefmetazol significantly increases the binding capacity of human lymphocyte receptors CD2 to sheep red blood cells while Imipenem does not alter this binding. The number of Fc lymphocyte receptors for the constant fraction of IgG is found to be significantly increased when the lymphocytes are incubated in vitro with Imipenem and Cefmetazol. When the lymphocytes are treated with these antibiotics there is an increase in the receptors capable of binding to fraction C3b of the complement.  相似文献   
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