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OBJECTIVE: This study determined whether genomic amplification of HER-2/neu or mutations of the p53 and ras genes were present in gastrinomas. SUMMARY BACKGROUND DATA: Amplification of HER-2/neu, a proto-oncogene related to the epidermal growth factor receptor, and mutation of the ras proto-oncogene and p53 tumor suppressor gene appear to play a role in the pathogenesis of some human cancers. Little is known about possible molecular alterations in gastrinomas, tumors that may be particularly virulent because of gastrin overproduction, resulting in the severe ulcer diathesis, the Zollinger-Ellison syndrome. METHODS: The differential polymerase chain reaction (PCR) procedure was used to detect amplification of the HER-2/neu gene in DNA samples from the novel human gastrinoma cell line (PT) and from paraffin-embedded samples of gastrinomas. Sequencing techniques were used to determine whether mutations of the p53 or ras (Ha-ras, N-ras, Ki-ras) genes were present. RESULTS: Amplification (> twofold) occurred in all gastrinoma tumor samples. Compared with normal pancreas or ileum, a 4- to 12-fold amplification of HER-2/neu was found in 3 gastrinomas, 3 to 3.3-fold in four samples and 2.1- to 2.4-fold in the remaining five tumors. A heterozygous point mutation in the p53 gene (codon 273) was found in a single sample; none of the gastrinomas contained a mutation of the ras genes. CONCLUSIONS: Amplification of the HER-2/neu gene, but not alterations of either p53 or ras, may be involved in the pathogenesis of gastrinomas. The unique PT cell line will be a useful model to further elucidate the molecular mechanisms that contribute to gastrinoma formation and growth.  相似文献   
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Context  Herpes simplex virus type 2 (HSV-2) is one of the most common sexually transmitted infections in the United States. No prospective study has shown the ability of condoms to reduce transmission of HSV-2. Objective  To evaluate risk factors for HSV-2 acquisition and efficacy of condoms in prevention of HSV-2 transmission. Design  Analysis of data from a randomized, double-blind, placebo-controlled trial conducted December 13, 1993, to June 28, 1996, of an ineffective candidate HSV-2 vaccine with 18 months of follow-up. Setting  Eighteen clinical trial centers in the United States. Participants  A total of 528 monogamous couples discordant for HSV-2 infection, including an HSV-2–susceptible population of 261 men and 267 women. Main Outcome Measure  Acquisition of HSV-2 infection by susceptible partners, compared with those remaining free of HSV-2 with regard to demographic characteristics, sexual activity, and condom use. Results  Twenty-six women (9.7%) vs 5 men (1.9%) acquired HSV-2, for a rate per 10 000 sex acts (episodes of sexual intercourse) of 8.9 vs 1.5, respectively (P<.001). In multivariable analysis, younger age (adjusted hazard ratio [HR] per 5 years, 1.57; 95% confidence interval [CI], 1.22-2.04), seropositivity for HSV-1 and HSV-2 vs HSV-2 alone in the source partner (adjusted HR, 2.34; 95% CI, 1.14-4.82), and more frequent sexual activity (adjusted HR per additional sex act per week, 1.10; 95% CI, 1.01-1.19) were associated with higher risk of HSV-2 acquisition. Condom use during more than 25% of sex acts was associated with protection against HSV-2 acquisition for women (adjusted HR, 0.085; 95% CI, 0.01-0.67) but not for men (adjusted HR, 2.02; 95% CI, 0.32-12.50). Risk of HSV-2 transmission declined from 8.5 per 100 person-years in the initial 150-day interval to 0.9 per 100 person-years in the final 150-day interval (P = .002 for trend), concurrent with a decrease in sexual activity and proportion of sex acts occurring when the source partner had genital lesions. Conclusions  Condom use offers significant protection against HSV-2 infection in susceptible women. Changes in sexual behavior, correlated with counseling about avoiding sex when a partner has lesions, were associated with reduction in HSV-2 acquisition over time. These data suggest that identification of discordant couples can reduce transmission of HSV-2, especially for heterosexual couples in which the male partner has HSV-2 infection.   相似文献   
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A Guide to Immunotherapy of Genital Warts   总被引:1,自引:0,他引:1  
Genital warts affect at least 1% of sexually active adults. Current therapies are inadequate because they are often painful, may fail to prevent recurrence and transmission of warts, and usually require either surgery or at least application by a physician. Investigation of immunotherapy for genital warts began with interferon. It has been studied in topical, intralesional, systemic and adjuvant applications. We review the major clinical trials of interferon for genital warts, and conclude that intralesional therapy with interferon-alpha or interferon-beta, with complete response rates of 36 to 63%, is the most successful route for interferon monotherapy. In choosing patients for therapy with interferon, major considerations include immune status, pregnancy and ability to return for frequent injections. Imiquimod is a new immune response enhancer that acts through stimulating host cytokine production. Interleukins-1, -2, -6, -8 and -12, interferons alpha, beta and gamma and tumour necrosis factor alpha have all been associated with the mechanism of action of imiquimod. Recently, 3 clinical trials have reported positive results using topical imiquimod to treat genital warts. Complete response rates ranged from 37 to 54% for these controlled trials of 5% imiquimod cream. Adverse effects reported include localised pruritis, erythema, erosion, burning and pain, which were rarely severe enough to cause discontinuation of the medication. Although further trials are necessary to identify the role of imiquimod in the therapy of genital warts, it appears to be an efficacious and well tolerated patient-controlled measure for wart therapy.  相似文献   
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The University of Texas Medical Branch (UTMB) is the first Texas site to test an HIV vaccine. The effectiveness of the vaccine in preventing HIV is being studied, but it cannot give a person AIDS; it is genetically engineered and therefore contains copies of proteins normally found on the surface of the virus. The vaccine has already been tested for safety in animals. This vaccine and a similar formulation have been given to more than 1,200 human volunteers, with no serious side effects reported. Vaccine approaches that are in development or in clinical trials are detailed. Contact information for the UTMB trial is provided.  相似文献   
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背景:银屑病对患者心理和情绪影响很大。依那西普治疗银屑病患者临床症状有效,作者评估了该药对银屑病相关疲劳和抑郁症状的疗效。方法:618例中至重度银屑病患者接受安慰剂或依那西普50mg(2次/周)双盲治疗。主要疗效终点:治疗12周时,银屑病面积和严重度指数评分较基线改善达75%(PASI 75)或更高水平;次要和其他疗效终点:慢性病治疗疲劳功能评估(FACIT-F)分级、Hamilton抑郁量表(Ham-D)分级、Beck抑郁列表(BDI)及不良事件。根据分组治疗进行疗效分析。基于实际接受治疗的情况对安全性资料进行分析和总结。  相似文献   
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To discover novel biomarkers of psoriasis, a target‐specific antibody array screening of serum samples from psoriasis patients was initially performed. The results revealed that vascular endothelial growth factor receptor 3 (VEGFR‐3) was significantly elevated in the sera of psoriasis patients, compared to healthy controls. Next, ELISA validation studies in a larger cohort of psoriasis patients (N = 73) were conducted, which confirmed that serum VEGFR‐3 was indeed significantly increased in patients with psoriasis compared to healthy controls (P < 0.001). Furthermore, receiver operating characteristic curve analysis demonstrated that serum VEGFR‐3 exhibited potential in distinguishing healthy controls from psoriasis patients: area under the curve = 0.85, P < 0.001. In addition, serum levels of VEGFR‐3 were correlated with Psoriasis Area Severity Index scores (R = 0.32, P = 0.008) in psoriasis patients. Interestingly, serum VEGFR‐3 levels were significantly elevated in psoriatic arthritis compared to non‐psoriatic arthritis (P = 0.026). A pilot longitudinal study demonstrated that serum levels of VEGFR‐3 could reflect disease progression in psoriasis. Collectively, serum VEGFR‐3 may have a clinical value in monitoring disease activity of psoriasis.  相似文献   
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