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61.
BACKGROUND: Recent studies suggest that parental sun protective behaviors and communication influence their adolescents. However, there is limited information on sun protection for parents of adolescents. METHODS: A telephone-based, nationally representative prevalence study of sun exposure among youth, aged 11-18, and their parents living in households was conducted in 1998. Separate, independent responses were collected. Weighted prevalence estimates and 95% confidence intervals were estimated and presented for parents only (n = 1187). RESULTS: Approximately one-third of parents planned activities to avoid the sun and used sunscreen. Among parents who used sunscreen, 70% applied it while at the beach or pool, but not as often during other outdoor activities. Almost one-third of parents were participating in water or non-water recreational activities during their most serious sunburn. Differences in sun protection and sunburn experiences were observed by age, gender, sun sensitivity, race and ethnicity, and educational attainment. CONCLUSIONS: Parents have adopted sun protection habits, but have not surpassed national sun-protection goals. Combined use of sun protection behaviors may reduce sunburn prevalence and number of incident skin cancers. These data may be useful for developing or enhancing current sun protection programs for effective sun protection that include parents and their adolescents. 相似文献
62.
63.
Pertosa G Simone S Soccio M Marrone D Gesualdo L Schena FP Grandaliano G 《Journal of the American Society of Nephrology : JASN》2005,16(8):2477-2486
Priming of the coagulation cascade during hemodialysis (HD) leads to the release of activated factor X (FXa). The binding of FXa to its specific receptors, effector protease receptor-1 (EPR-1) and protease-activated receptor-2 (PAR-2), may induce the activation of peripheral blood mononuclear cells (PBMC) and promote a chronic inflammatory state that is responsible for several HD-related morbidities. In the attempt to elucidate the mechanisms underlying the coagulation-associated inflammation in HD, 10 HD patients were randomized to be treated subsequently with a cellulose acetate membrane (CA) and Ethylen-vinyl-alcohol (EVAL), a synthetic membrane that has been shown to reduce FXa generation. At the end of each experimental period, surface FXa and thrombin receptors (EPR-1 and PAR-1, -2, and -4) and CCR2 (monocyte chemoattractant protein-1 receptor) gene expression in isolated PBMC were examined. the ability of dialytic membranes to activate protein-tyrosine kinases and the stress-activated kinase JNK and to modulate the generation of terminal complement complex (TCC) was also investigated. EPR-1 and PAR-2 and -4 mRNA expression, barely detectable in normal PBMC, were significantly upregulated in HD patients, particularly in those who were treated with CA. A striking increase of tyrosine-phosphorylated proteins and JNK activation was observed at the end of HD only in CA-treated patients. Simultaneously, an increased gene expression for both splicing isoforms of CCR2, A and B, only in PBMC from CA-treated patients was demonstrated. The increased CCR-2 mRNA abundance was followed by a significant increase in its protein synthesis. The high expression of CCR2 was associated with an increased generation of plasma TCC and a significant drop in leukocyte and monocyte count. By contrast, EVAL treatment slightly lowered TCC generation and normalized leukocyte count. In vitro FXa induced CCR2 A and B expression and JNK activation in freshly isolated PBMC. FXa-induced CCR2 mRNA expression was completely abolished by JNK and tyrosine kinase inhibition. In conclusion, these data suggest that subclinical clotting activation may cause an increased CCR2 gene and protein expression on uremic PBMC, contributing to HD-related chronic microinflammation. The use of the less coagulation-activating membrane, EVAL, may reduce PBMC activation through the modulation of the stress-activated kinase JNK. 相似文献
64.
Alvarez L Jara P Hierro L Sánchez-Sabaté E Martínez-Fernández P López-Santamaría M 《Seminars in Pediatric Surgery》2005,14(4):200-205
Cholestasis constitutes one of the most common and severe manifestations of acquired or inherited liver disease. When manifest in early infancy, it is often life-threatening and usually requires surgical management. In many cases, liver transplantation is the only effective therapy. Extensive knowledge about the molecular mechanisms underlying several pediatric cholestatic disorders has been gained in recent years from studies in both experimental models and clinical forms. In this review, we focus on recent contributions to the knowledge of molecular basis of main pediatric cholestatic disorders, such as biliary atresia, Alagille syndrome, and familial intrahepatic cholestasis. For some of them, putative targets of therapeutic interest, such as interferon-gamma and Farnesoid X receptor, have been proposed. 相似文献
65.
Tapia-Aguirre V Arillo-Santillán E Allen B Angeles-Llerenas A Cruz-Valdéz A Lazcano-Ponce E 《Archives of medical research》2004,35(4):334-343
BACKGROUND: This school-based study explored associations between Mexican young people's condom use, other sexual behaviors, and HIV/AIDS knowledge. METHODS: Students (n=13,293, 11-24 years of age) from a random sample of public schools in the central Mexican state of Morelos completed a self-administered questionnaire. We performed logistic regression analysis of condom use and sexual behavior variables and a knowledge-based index on HIV/AIDS prevention and transmission. RESULTS: Average age at sexual debut was 13.6 +/- 1.9 years among young men and 14.2 +/- 2.2 years among young women; 34.5% of sample participants reported using condoms during their first sexual intercourse. More students had intermediate HIV/AIDS knowledge levels (46%, 95% confidence interval [95% CI], 45.2-46.9) than high levels (37%, 95% CI 36.2-37.8, p <0.01). Students knew more concerning HIV transmission than about prevention of HIV infection. Among young men, high levels of HIV/AIDS knowledge increased likelihood of condom use (odds ratio [OR] 1.4, 95% CI, 1.1-1.7), while among young women high levels of knowledge decreased likelihood of using condoms (OR 0.7, 95% CI, 0.5-1.0). Young men with high levels of HIV/AIDS knowledge were more likely to have had three or more sexual partners (OR 1.7, 95% CI, 1.3-2.2), but young women with high knowledge levels were more likely to have only one lifetime sexual partner (OR 0.6, 95% CI, 0.4-0.9). CONCLUSIONS: As in previous studies in smaller samples, levels of knowledge with regard to HIV/AIDS were low in Mexican youth. HIV/AIDS education programs for Mexican students should focus on conveying knowledge on HIV prevention. Because apparently knowledge is not directly correlated with condom use among young women, prevention strategies that deal with social acceptability of condoms and social skills related with condom negotiation are also needed. 相似文献
66.
Effect of adrenomedullin on c-Met receptor expression after reserpine-induced gastric damage in the rat 总被引:1,自引:0,他引:1
Martinez G Cantarella G Cutuli VM Loreto C Prato A Lempereur L Carnazza ML Amico-Roxas M Bernardini R Clementi G 《European journal of pharmacology》2004,488(1-3):219-224
Here, we show an increase in c-Met receptor expression during reserpine-induced gastric damage in the rat, as assessed by immunohistochemistry. Pretreatment of animals with adrenomedullin prevented this increase in c-Met expression. c-Met immunoreactivity was localized in gastric glands. c-Met immunoreactivity was associated with increased phosphorylation of c-Met receptor and extracellular signal-regulated kinase (ERK(1/2)). Our results suggest that both adrenomedullin and c-Met act as parallel defence mechanisms during pharmacologically induced gastric mucosa injury. 相似文献
67.
Lopes G Gazola VA Galende SB Alves-do-prado W Curi R Bazotte RB 《Acta pharmacologica Sinica》2004,25(10):1257-1261
AIM: To compare the acute effects of l-carnitine (LCT) and dl-carnitine (DLC) on hepatic catabolism of l-alanine and l-glutamine in rats. METHODS: Livers from 24 h fasted and fed rats were perfused in situ. The substrates l-alanine (5 mmol/L) and l-glutamine (5 mmol/L) were employed. The gluconeogenic and ureogenic activity was measured as the difference between the rates of glucose and urea released during and before the infusion of l-glutamine or l-alanine. RESULTS: LCT (60 μmol/L) but not DLC (60 μmol/L and 120 μmol/L) increased the production of glucose and urea from l-glutamine. However, neither LCT (60 μmol/L and 120 μmol/L) nor DLC (60μmol/L and 240 μmol/L) showed any significant effect on hepatic glucose and urea production from l-alanine. CONCLUSION: The results showed a different acute effect of LCT and DLC on the activation of hepatic gluconeogenesis and ureagenesis promoted by l-glutamine, reinforcing the idea that DLC could not replace LCT. 相似文献
68.
Casarsa S Puglisi F Baudi F De Paola L Venuta S Piga A Di Loreto C Marchesoni D D'Elia AV Damante G 《Oncology reports》2004,12(2):313-316
Germline mutations of BRCA1 and BRCA2 genes confer susceptibility to breast and ovarian cancer. It has been recently reported that BRCA1/2 mutations may also predispose to fallopian tube cancer. We report the presence of germline BRCA2 gene mutations in three out of four subjects with fallopian tube cancer diagnosed in a two-year time span at our clinic. The mothers of two of these women suffered from breast or ovarian carcinoma. These results suggest on one hand that in patients with a history suggestive for a heredofamilial breast/ovarian cancer syndrome fallopian tube carcinoma is associated with high risk of BRCA2 mutation, and on the other hand that in patients/individuals with germline BRCA2 gene mutations in whom a prophylactic oophorectomy is performed, removal of fallopian tubes may be considered. 相似文献
69.
Hepatitis C virus infection associated with liver-kidney microsomal antibody type 1 (LKM1) autoantibodies in children 总被引:5,自引:0,他引:5
Bortolotti F Muratori L Jara P Hierro L Verucchi G Giacchino R Barbera C Zancan L Guido M Resti M Pedditzi S Bianchi F Gatta A 《The Journal of pediatrics》2003,142(2):185-190
OBJECTIVE: To evaluate the clinical pattern and evolution of chronic hepatitis C in children with liver/kidney microsomal antibody type 1 autoantibodies (LKM1). STUDY DESIGN: A multicenter, retrospective study, including the following groups of children with hepatitis C virus infection: (1). 21 consecutive LKM1-positive patients, (2). 42 age- and sex- matched LKM1-negative patients, and (3). 4 interferon-induced LKM1-positive cases. LKM1 reactivity to human microsomes and recombinant cytochrome P450IID6 (CYP2D6) was assayed by immunoblotting. RESULTS: Clinical and biochemical features overlapped in LKM1-positive and LKM1-negative children, but a fibrosis score >3 (range 0-6) was significantly more frequent (P =.04) in the former. Reactivity to microsomal protein and CYP2D6 was significantly (P =.02) associated with LKM1 titers >or=1:320 and was found in 39% of patients, including severe cases and both children (of 4 treated) who achieved a sustained alanine aminotransferase (ALT) normalization after steroid treatment. Five of 7 LKM1-positive children treated with interferon had an ALT exacerbation. CONCLUSIONS: LKM1-positive hepatitis C in children is characterized by a wide spectrum of biochemical, serologic, and histologic features. Whether autoimmunity may contribute to liver damage in a subgroup of patients with more severe liver disease, high LKM1 titers, and reactivity to CYP2D6 is a question deserving further investigation. 相似文献
70.
Clinical features and progression of perinatally acquired hepatitis C virus infection 总被引:1,自引:0,他引:1
Resti M Jara P Hierro L Azzari C Giacchino R Zuin G Zancan L Pedditzi S Bortolotti F 《Journal of medical virology》2003,70(3):373-377
The purpose of this prospective-retrospective study was to provide information about the clinical features and progression of hepatitis C virus (HCV) infection transmitted perinatally. Seventy children born to HCV infected woman were enrolled consecutively in five European centers between 1990 and 1999, provided they had HCV RNA in the serum during the first year of life and/or were still anti-HCV positive at 18 months. Sixty-two infants were followed up to 24 months of age or more (range, 24 months-11 years; average, 4.8 +/- 2.3 years). A wide range of ALT elevation was observed in 93% of the infants in the first year of life. During the follow-up, a sustained ALT normalization with loss of HCV RNA was seen in 12/62 (19%) of the children within 30 months of life; 66% of the infants had developed an ALT peak greater than 5x normal at onset (vs. 28% of children with persistent viremia; P < 0.05), and 50% had HCV genotype 3 (vs. 17% of viremic children). Conversely the cumulative probability of chronic progression was 81%. Chronic infection was asymptomatic and liver disease was mild in all 11 children who underwent a biopsy. In conclusion the early stage of acquired perinatally HCV infection is characterized by a wide range of ALT abnormalities, suggesting the interaction of multiple host and virus factors. The chronic progression rate of infection is high, but the associated liver disease is usually mild. High ALT levels at onset seem to offer greater opportunity of biochemical remission and loss of viremia during follow-up. 相似文献