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71.
Using limited proteolytic analyses, we show that gE present in soluble herpes simplex virus type 1 gE-gI complexes is cleaved into a C-terminal (CgE) and an N-terminal (NgE) domain. The domain boundary is in the vicinity of residue 188 of mature gE. NgE, but not CgE, forms a stable complex with soluble gI.  相似文献   
72.
The current study aimed at evaluating the ability of a mineral and antioxidant-rich extract from Chondrus canaliculatus to improve maneb (MB)-induced toxicity in adult rat. The animals were divided into four groups: group 1 used as a control group, group 2 received MB, group 3 received MB + C. canaliculatus extract, and group 4 received only the algal extract. MB, a Mn-containing ethylene-bis-dithiocarbamate fungicide, induced oxidative stress damages, mineral perturbations in the plasma, urine, and bone, and genotoxicity in rats. Hematological analysis revealed in the MB-treated group a disruption in the number of red blood cells, platelets, and white blood cells associated with a striking genotoxicity. Interestingly, a significant increase in malondialdehyde and advanced oxidation protein product levels in erythrocytes and bones were found. On the other hand, an impairment of the antioxidant status in both tissues was occurred. Along, our results revealed that MB injection caused a striking drop and disruption in bone’s mineral rates, especially calcium and phosphorus. These biochemical results were in accordance with the histological and molecular changes. However, co-treatment with C. canaliculatus extract showed, for the first time, that this alga was effective against MB-induced hematotoxicity, genotoxicity, and oxidative stress in the blood and bone and maintained osteomineral metabolism and bone histo-architecture. Such observations might be explained by the strong in vitro antioxidant and antibacterial activities exhibited by the alga, as well as by its high levels in several minerals: calcium, phosphorus, sodium, potassium, magnesium, iron, and zinc.  相似文献   
73.
The use of Vero cells for rabies vaccine production was recommended from the WHO in 2005. A controlled production process is necessary to reduce the risk of contaminants in the product. One step towards this is to turn away from animal-derived components (e.g. serum, trypsin, bovine serum albumin) and face a production process in animal component-free medium. In this study, a proteomic approach was applied, using 2-D differential gel electrophoresis and mass spectrometry to compare rabies virus propagation in Vero cells under different cultivation conditions in microcarrier culture. Protein alterations were investigated for uninfected and infected Vero cells over a time span from 1 to 8 days post-infection in two different types of media (serum-free versus serum-containing media). For mock-infected cells, proteins involved in stress response, redox status, protease activity or glycolysis, and protein components in the endoplasmic reticulum were found to be differentially expressed comparing both cultivation media at all sampling points. For virus-infected cells, additionally changes in protein expression involved in general cell regulation and in calcium homeostasis were identified under both cultivation conditions. The fact that neither of these additional proteins was identified for cells during mock infection, but similar protein expression changes were found for both systems during virus propagation, indicates for a specific response of the Vero cell proteome on rabies virus infection.  相似文献   
74.
A polymorphic AC repeat in intron 1 of the EGFR gene was genotyped on 352 healthy individuals and 118 women with breast cancer sampled from the Kuwaiti and Tunisian populations. We compared allele frequencies in these populations with published data on various ethnic groups. We found very close similarity between Tunisian and Kuwaiti populations for both allelic and genotypic frequencies and in both control and patient groups. Our analysis revealed clear interethnic differences between populations; in Europeans, allele 16 occurred predominantly, whereas in Tunisia and Kuwait allele 17 was the most frequent and allele 20 predominated in Asians. One hundred twenty-three healthy women, matched with the 118 breast cancer patients, were used as controls to test for associations between AC repeat and cancer risk. Strong evidence for such an association was found for allele 18 when considered alone (chi2=27.04, corrected p=0.0000016, OR=3.94) or with longer alleles (>17 repeats) (chi2=20.21, p=0.0005, OR=2.30). This contrasts with Asian populations where allele 16 was identified as the risk allele, showing allele heterogeneity depending on ethnicity.  相似文献   
75.
The analysis of the total lipid fraction from the Sayali variety of olive oil was accomplished in the present investigation. Glyceridic, unsaponifiable and flavour fractions of the oil were isolated and identified using several analytical methods. Chromatographic techniques have proven to be suitable for these determinations, especially capillary gas chromatography. Gas chromatography coupled to mass spectrometry was successfully used to identify sterols, triterpenes alcohols, 4-monomethylsterols, aliphatic alcohols and aroma compounds in our samples. Furthermore, solid phase microextraction was used to isolate volatiles from the total lipid fraction. Results from the quantitative characterization of Sayali olive oil showed that oleic acid (77.4%) and triolein (47.4%) were the dominant glyceridic components. However, the main compounds of the unsaponifiable fraction were β-sitosterol (147.5 mg/100 g oil), 24-methylene cycloartenol (146.4 mg/100 g oil) and hexacosanol (49.3 mg/100 g oil). Moreover, results showed that the aldehydic compounds were the major flavours present in Sayali olive oil.  相似文献   
76.
Phosphoenolpyruvate carboxylase (PEPc: EC 4.1.1.31) activity was monitored during seed maturation of two varieties (Hybridol and Pactol) of rapeseed (Brassica napus L.), widely cultivated in Tunisia. In the Hybridol variety, PEPc activity did not exceed 5 micromol h(-1) per gram of fresh weight (FW) during the first stages of maturation. It then highly increased to reach more than 30 micromol h(-1) g(-1)/FW. On the contrary, in the Pactol variety, the evolution of PEPc activity showed a classical curve, i.e. an increase during the most active phase of lipid accumulation in maturating seeds, followed by a rapid decrease until the end of seed maturation. In both varieties, the seed oil was characterised by a high content of oleic acid (C(18:1)), linoleic (C(18:2)) and linolenic acids (C(18:3)). Saturated fatty acids were also present, although decreasing with maturation course. The analysis of the triacylglycerols (TAG) showed that trioleoylglycerol (OOO) and dioleoyllinoleoylglycerol (OOL) were the major species (ca. 35% and ca. 25% of the total respectively). The evolution pattern of fatty acids and TAG contents was similar to that of PEPc activity. Taken together, our findings suggest that PEPc may be involved in fatty acid and triacylglycerol biosynthesis during seed maturation of both rapeseed varieties.  相似文献   
77.
Reactivation of latent Mycobacterium tuberculosis (Mtb) infection is a major complication of anti-tumour necrosis factor (TNF)-alpha treatment, but its mechanism is not fully understood. We evaluated the effect of the TNF antagonists infliximab (Ifx), adalimumab (Ada) and etanercept (Eta) on anti-mycobacterial immune responses in two conditions: with ex vivo studies from patients treated with TNF antagonists and with the in vitro addition of TNF antagonists to cells stimulated with mycobacterial antigens. In both cases, we analysed the response of CD4+ T lymphocytes to purified protein derivative (PPD) and to culture filtrate protein (CFP)-10, an antigen restricted to Mtb. The tests performed were lymphoproliferation and immediate production of interferon (IFN)-gamma. In the 68 patients with inflammatory diseases (rheumatoid arthritis, spondylarthropathy or Crohn's disease), including 31 patients with a previous or latent tuberculosis (TB), 14 weeks of anti-TNF-alpha treatment had no effect on the proliferation of CD4+ T lymphocytes. In contrast, the number of IFN-gamma-releasing CD4+ T lymphocytes decreased for PPD (p < 0.005) and CFP-10 (p < 0.01) in patients with previous TB and for PPD (p < 0.05) in other patients (all vaccinated with Bacille Calmette-Guérin). Treatments with Ifx and with Eta affected IFN-gamma release to a similar extent. In vitro addition of TNF antagonists to CD4+ T lymphocytes stimulated with mycobacterial antigens inhibited their proliferation and their expression of membrane-bound TNF (mTNF). These effects occurred late in cultures, suggesting a direct effect of TNF antagonists on activated mTNF+ CD4+ T lymphocytes, and Ifx and Ada were more efficient than Eta. Therefore, TNF antagonists have a dual action on anti-mycobacterial CD4+ T lymphocytes. Administered in vivo, they decrease the frequency of the subpopulation of memory CD4+ T lymphocytes rapidly releasing IFN-gamma upon challenge with mycobacterial antigens. Added in vitro, they inhibit the activation of CD4+ T lymphocytes by mycobacterial antigens. Such a dual effect may explain the increased incidence of TB in patients treated with TNF antagonists as well as possible differences between TNF antagonists for the incidence and the clinical presentation of TB reactivation.  相似文献   
78.
Vegetative insecticidal proteins were produced by some Bacillus thuringiensis strains and were successfully used in biological control against different agricultural pests such as Lepidoptera. To assess the safety of Vip3Aa16 toxins in mammalian organisms, we evaluated their toxicity using histological, hematological, and oxidative stress parameters on albino Swiss mice. The animals were orally treated with 2500, 5000, 7500 milligrams (mg) of the toxin/kilogram (kg) of body weight for 14 days. Then samples of blood, kidney and hepatic tissues were collected at the end of the treatment. Hematological parameters were monitored by RBC, WBC, hemoglobin, hematocrit, MCV, MCH, and MCHC. Liver and kidney MDA, SOD, vitamin C and H2O2 were analyzed to assess oxidative damage. Hepatotoxicity was monitored by analysis of the plasma enzymes ALT and AST and bilirubin levels. Renal toxicity was tested by urea, uric acid and creatinine evaluation. The histopathology of kidney and liver tissues was also investigated. The results of the toxicological study revealed that the Vip3AaA16 has no lethal effect since no mortality was observed at any dose. Moreover, body weight, hematological, histological, biochemical and oxidative findings showed no significant differences between treated and control groups. All these findings confirmed that this toxin is highly safe and doesn’t represent any risk on animal health and subsequently, Vip3Aa16 toxin can be safely used in biological programs to control Lepidopteran pests attacking crops around the world.  相似文献   
79.
A field experiment was conducted to compare local chickpea (Giza 2) and its recently developed cultivar L3. The two genotypes were examined for biological dinitrogen fixation and P uptake as enhanced by inoculation withRhizobium (Rh) and/or arbuscular mycorrhiza (AM). Significant increase in dry mass was obtained by biological inoculation. Soil chemical and physical properties have a significant effect on the ability of the two genotypes to fix nitrogen on their P uptake and N content. Growth of the local genotype (G2) was pronounced in sandy loam soil as compared with the sandy one.  相似文献   
80.
Summary 121 cases diagnosed clinically as tinea capitis were examined microscopically and culturally. In 80 cases the causative organism could be cultured.T. violaceum was the causative organism of the majority of the cases as it caused 47.5 % of the cases,T. schoenleinii 31.3 %,M. canis caused 26.1 %,T. tonsurans 1.3 %, whileM. audouinii caused none. In most of the cases ofT. violaceum infection, scaling and mild inflammation were the common clinical manifestation. The black dot or the bald patch appearance was rarely seen. Favus did not necessarily show the characteristic scutulae; in many cases ofT. schoenleinii infection, only few scales and mild inflammation were present.  相似文献   
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