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11.
BACKGROUND: In earlier studies, it has been shown that severity of some diseases varies with menstrual cycle. Severity of skin diseases such as atopic dermatitis, lupus erythematosus, infections due to herpes virus, urticaria and acne were also reported to increase in the premenstrual phase. Effect of estradiol on the cellular immune system was investigated and it was found to depress the cellular immune response. In our study, we investigated whether nickel patch test reactivity was different during phases of the menstrual cycle and whether there was an increase in sensitivity to nickel during the premenstrual cycle in nickel-sensitive women. METHODS: The study consisted of 30 women who had a history of nickel sensitivity. Finn Chamber nickel patch test was applied to all 30 women by dividing them into two groups of 15 and applying the test first on days 7-10 and then on days 20-24 of the menstrual cycle or vice versa. RESULTS: The reactions of both the groups on days 20-24 were more severe than those on days 7-10 even though the results were not statistically significant. CONCLUSIONS: Estrogens not only impair the skin barrier but also have a negative impact on the immune system. Estradiol has been proved to suppress cellular immunity. In a few studies conducted to date, the relationship between phases of the menstrual cycle and the severity of patch test reactivity has been examined with equivocal results. In our study, we observed that the presence of reactions due to nickel sensitivity was independent of the phases of the menstrual cycle. Nevertheless, we would like to point out the fact that the reactions seen in the second phase of the menstrual cycle were more severe than those seen in the first phase.  相似文献   
12.
High levels of fatty acid synthase (FAS) have been found in cancer precursor lesions of the colon, stomach, esophagus, oral cavity, prostate, and breast. Inhibition of FAS with C75 has led to a significant antitumor effect in both human breast and prostate cancer xenografts. Recently, HER2/neu, which has also been identified in preneoplastic breast lesions, has been shown to regulate FAS expression through the PI3K/Akt signal transduction pathway rendering them susceptible to FAS inhibition. Utilizing the neu-N transgenic mouse model of mammary cancer, weekly treatment of the neu-N mice with C75 (30 mg/kg) for 10 weeks significantly delayed tumor progression. Only 20% of the C75-treated transgenic mice developed mammary carcinoma by 220 days, compared to 50% in the vehicle control animals. Two C75-treated animals never developed mammary cancer. Analysis of mammary tissue following 10 weeks of C75 treatment revealed a significant delay in mammary maturation as manifested by a reduction of the number and caliber of mammary ducts and budding epithelial structures. Apoptotic changes were increased, DNA synthesis was decreased, and the expressions of FAS, neu, Akt, phospho-Akt, and p21(waf1) were all decreased when compared to vehicle controls and FVB/N mice. Importantly, these effects were restricted to the breast epithelial cells that overexpressed neu, not involving other normal duct structures in the skin, liver, or kidney. C247, an FAS inhibitor chemically distinct from C75, significantly delayed mammary maturation similar to C75. Thus, pharmacological inhibition of FAS affects the expression of key oncogenes involved in both cancer development and maintenance of the malignant phenotype. Moreover, these data identify FAS as a potential novel drug target for breast cancer chemoprevention.  相似文献   
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Background Immune dysregulation has been shown to be one of the major aspects of the yet unknown pathogenesis of Behçet's disease. Interleukin-8 (IL-8), a major chemokine with pivotal effects concerning leukocytes and endothelial cells, has been found to be elevated in patients with Behçet's disease. Aim To evaluate the significance of elevated levels of IL-8 with respect to the activity of Behçet's disease. Methods Sixty-seven consecutive patients with Behçet's disease (37 males, 30 females; 32.5 ± 9.3 years) were enrolled in our study. The number of active clinical manifestations at the time of serum sampling was recorded. The degree of association between disease activity and IL-8, C-reactive protein, and erythrocyte sedimentation rate was assessed. Results Serum levels of IL-8 increased as the number of clinically involved organs increased (P < 0.05). C-reactive protein and the erythrocyte sedimentation rate showed no correlation with disease activity. Conclusions Our study confirms that the IL-8 level is a more sensitive marker of disease activity than the erythrocyte sedimentation rate and C-reactive protein. It may be assumed that IL-8 plays an important role in the pathophysiology of Behçet's disease.  相似文献   
14.
Proteins and lipids, both individually or as complexes, play important functional roles in foods. Since the 1970s food scientists have devoted attention to the nature of these interactions and particularly to their effects on functional characteristics of protein-based foods. Previously, most of the published work was devoted to the biochemical aspects of protein-lipid interactions in biological systems. This article reviews the protein-lipid interactions of both naturally occurring protein-lipid complexes and protein-lipid complexes formed by induced interactions in foods and food products. The physicochemical characteristics of known protein-lipid complexes, the nature of binding which results in formation of these complexes and the effect of the interactions on food functionality are reviewed.  相似文献   
15.
Russula delica Fr. is a well known macrofungi which is used as a food in Turkey. The ethanolic extract of R. delica exhibited antimicrobial activity against some of the tested foodborne and spoilage bacteria. The phenolic composition of R. delica ethanolic extract was analyzed by high performance liquid chromatography (HPLC). The major component in R. delica ethanolic extract was catechin (5.33 mg/L). Antioxidant activities of the ethanolic extract of R. delica was evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging and chelating ability on ferrous ions assays. Scavenging effect on DPPH radicals was 26% at 10 mg/ml and chelating effects on ferrous ions was 58% at 5 mg/ml. In addition, the amounts of total phenol content (6.23 mg/g), ascorbic acid (2.93 mg/g), β-carotene (0.11 mg/g) and lycopene (0.03 mg/g) in the macrofungi ethanolic extract were determined.  相似文献   
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It has been suggested that the heart plays an active role in the pathogenesis of arterial hypertension. If this is true, there must be early cardiac involvement in young normotensive subjects who develop hypertension later in life and differences in cardiac morphology or function may exist between young normotensive subjects with different risks of developing hypertension. M-mode echocardiography was performed in 51 normotensive male adolescents with at least one hypertensive parent (SHT). These subjects were compared with 55 normotensive sons of normotensive parents (SNT) and with 25 adolescents with borderline hypertension (BH). Control groups were matched for sex and age. The following morphologic parameters were significantly greater in the SHT group than in the SNT group: interventricular septum (0.54 +/- 0.08 vs 0.49 +/- 0.09 cm/m2; p less than 0.01) and posterior wall (0.54 +/- 0.11 vs 0.50 +/- 0.08 cm/m2; p less than 0.05) thickness, left ventricular mass (125.0 +/- 29.1 vs 109.2 +/- 25.4 gm/m2; p less than 0.005), and cross-sectional area (9.9 +/- 1.8 vs 8.9 +/- 1.6 cm2/m2; p less than 0.005). No significant differences between SHT and BH subjects were observed. Excursion of left ventricular posterior wall was significantly higher in the BH group. No differences were observed between SHT and SNT subjects. These data show that the same kinds of changes in cardiac morphology are present in normotensive subjects with a family history of hypertension and in subjects with borderline hypertension, suggesting that cardiac involvement may precede elevation of blood pressure.  相似文献   
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