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51.
A new lignan glucoside was isolated from defatted sesame seed flour and its structure was established as sesamolinol diglucoside [2-(3-methoxy-4-(O-beta-D-glucopyranosyl (1-->6)-O-beta-D-glucopyranoside)phenoxyl)-6-(3,4-methylenedioxyphenyl)-cis-3,7-dioxabicyclo-(3.3.0)-octane] by mass and nuclear magnetic resonance spectroscopy. A quantitative analysis of 65 sesame seed samples showed that this sesamolinol diglucoside ranged from <5 to 232 mg/100 g of seeds (98+/-57 mg/100 g) with no difference between white and black sesame seeds.  相似文献   
52.
H. pylori persistent infection induces chronic gastritis and is associated with peptic ulcer disease and gastric carcinoma development. The severity of these diseases is related to human’s genetic diversity, H. pylori genetic variability and environmental factors. To identify the prevalence of histo-pathological damages caused by H. pylori infection in Moroccan population, and to determine their association to H. pylori genotypes, a prospective study has been conducted during 3 years on patients attending the gastroenterology department of Hassan II University Hospital (CHU) of Fez, Morocco. A total of 801 Moroccan adults’ patients were recruited; H. pylori was diagnosed and genotyped by PCR in biopsy specimens and histological exam was performed. We found a high rate of glandular atrophy. Chronic inflammation, neutrophil activity and glandular atrophy showed statistically significant association with H. pylori infection. However, intestinal metaplasia was inversely associated to this infection and no association was observed with gastric cancer cases. A statistically significant association was found between intestinal metaplasia and vacAs1 and vac Am1 genotypes in patients aged 50 years and more but not in younger. This last genotype is also associated to gastric cancer. In this study, gastric cancer showed no significant association with H. pylori. Further studies are warranted to determine the role of other etiological agents such as Epstein-Barr virus, human papillomavirus and possibly environmental and dietetic factors in the occurrence of this pathology.  相似文献   
53.
In developing countries, cross‐breeding between local breeds and indigene or exotic breeds represents one of the main threats to the livestock diversity, leading to genetic dilution and loss of unique allelic combination underlying essential local adaptive traits. In this study, two Algerian sheep breeds, known to be highly admixed, were considered as a case study, to demonstrate how combination of different methodologies coupled with the use of specific softwares can be efficient to assess the spatial structuration of a hybrid zone, even in a case of extreme admixture. A fine sampling covering distribution areas of both breeds was implemented in order to study the admixture area and adjacent zones from a phenotypic (i.e., 19 quantitative traits were considered) and a genetic point of view (i.e., 21 microsatellites markers were used). Both approaches gave concordant patterns, highlighting areas with sheep most differentiated (or less admixed) for each breed. In detail, the region of Biskra appeared as the most preserved for the Ouled‐Djellal breed and the northwest of Laghouat was identified as the most preserved area for the Rembi breed. The approach proposed in the study offers a low‐cost solution to identify the most representative flocks of a breed, allowing the implementation of efficient conservation plans.  相似文献   
54.
Most polycyclic aromatic hydrocarbons (PAHs) are ubiquitous natural and/or anthropogenic pollutants that have adverse effects on the human health and the environment. Little is known about their potential effects on arbuscular mycorrhizal fungi (AMF). Thus, using monoxenic cultures, this work aims to study the impact of increasing concentrations (140 and 280 μM) of two PAHs [anthracene and benzo[a]pyrene (B[a]P)] on Glomus irregulare lipid content in relation with its development. Changes in the total lipids [fatty acids (FA), sterols, phospholipids (PL) and their associated FA (PLFA)] compositions and contents as well as [malondialdehyde (MDA)] production, of the AMF G. irregulare were examined. Direct toxic effects of both PAHs on the AMF were shown as compared to the control culture. The extraradical hyphae length and spore production were drastically restricted in the presence of PAHs. Significant decreases of the main membrane constituents, phosphatidylcholine (PC) and sterols (in particular 24-methycholesterol) were shown in G. irregulare grown under PAHs treatment. Moreover, PAHs exposure caused an oxidative stress in the AMF extraradical structures pointed out by an increase of the lipid peroxidation biomarker production (MDA). All the observed changes were less marked in presence of anthracene, which was found to be less toxic than B[a]P. Taken together, our results suggested that the drastic decrease of the AMF growth under PAHs pollution could partially be explained by depletions in sterols, PC and MDA accumulation.  相似文献   
55.
ABSTRACT: Inflammatory myofibroblastic tumor is a rare benign lesion whose tumor origin is now proven. It represents 0.7% of all lung tumors. We report the case of a three-year-old child who suffered from a chronic cough with recurrent respiratory infections. Chest X-ray and computed tomography revealed the presence of a left lower lobe lung mass. After pneumonectomy, histological examination combined with immunohistochemical study discovered an inflammatory myofibroblastic tumor. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8722069326962972.  相似文献   
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Isolated splenic metastases of colorectal cancers are very rare but possible even after several years of remission. We report the case of a 74-year-old man who developed isolated metachronous splenic metastasis of left colon cancer 5 years after the treatment of the primary tumor. Splenic metastasis was found by imaging examinations. The patient underwent splenectomy and the histological examination confirmed the metastatic nature of the splenic lesion. 18F-FDG PET allows both staging and resectability of these isolated metachronous splenic metastasis because a long-term survival can be achieved by splenectomy.  相似文献   
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Aflatoxin M1 in breast milk of nursing Sudanese mothers   总被引:1,自引:0,他引:1  
The presence of aflatoxin M1 (AFM1) in the breast milk of nursing Sudanese mothers was investigated using AOAC official method 980.21 as the extraction method and HPLC with fluorescence detector for separation and detection. Following informed consent, 94 breast milk samples of mothers were collected, and 51 samples were found to be positive for AFM1, with an average concentration of 0.401?±?0.525?ng?g?1 and a maximum level of 2.561?ng?g?1. The volunteers completed a questionnaire concerning their dietary preferences. The data collected suggest that peanut butter, vegetable oils and rice are the main sources responsible for the AFM1 burden in breast milk. The toxin levels are alarmingly high, and indicate that Sudanese infants are exposed to high levels of AFM1. A wide range of harmful effects, and consequently health problems, can be expected due AFM1 toxicity.  相似文献   
60.
Ornithine aminotransferase (OAT), proline oxidase (PO), Delta 1-pyrroline-5-carboxylate reductase (P5CR), and Delta 1-pyrroline-5-carboxylate dehydrogenase (P5CD) were assessed in Fasciola gigantica. All enzymes are involved in the conversion of ornithine into glutamate and proline. High levels of P5CD suggest that the direction of the metabolic flow from ornithine is more toward glutamate than proline. F. gigantica P5CD1 and P5CD2 were separated from the majority of contaminating proteins in crude homogenate using a CM-cellulose column. A Sephacryl S-200 column was employed for P5CD2 to obtain pure enzyme with increased specific activity. The molecular mass of P5CD2 was estimated to be 50kDa using a Sephacryl S-200 column and SDS-PAGE. It migrated as a single band on SDS-PAGE, indicating a monomeric enzyme. P5CD2 had Km values of 1.44mM and 0.37mM for NAD and P5C, respectively. P5CD2 oxidized a number of aliphatic and aromatic aldehydes, where the aromatic compounds had higher affinity toward the enzyme. All amino acids examined had partial inhibitory effects on the enzyme. While 3mM AMP caused 31% activation of enzyme, 3mM ADP and ATP inhibited activity by 18% and 23%, respectively. Apart from Cu2+, the divalent cations that were studied caused partial inhibitory effects on the enzyme.  相似文献   
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