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Background:  Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.
Methods:  We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results:  Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion:  An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma.  相似文献   
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Thiazolidinediones (TZDs), agonists of the nuclear receptor peroxisome proliferator-activated receptor-γ, induce the expression of many genes, including several enzymes and transporters involved in glucose and lipid metabolism. Although the efficacy of TZDs on blood glucose control in type 2 diabetes is not questionable, their cardiovascular effects have been debated, with beneficial or harmful actions suggested by different authors. This article reviews the available clinical evidence on the cardiovascular effects of TZDs, discussing possible mechanisms underlying the observed effects and suggesting some directions for future research.  相似文献   
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Since 1982, when the World Federation of Hemophilia first published a document on the state of the art of hemophilia diagnosis and care, there have been lights and shadows in this field. Although the widespread infection of hemophiliacs with the human immunodeficiency virus (HIV) contaminating clotting factor concentrates is still a threatening and formidable shadow, the gloomy picture brought about by the AIDS epidemic is partially lightened by spectacular improvements in therapy and diagnosis. Carrier detection and first-trimester prenatal diagnosis can now be performed accurately in most kindreds by analysis of DNA of the factor VIII or IX genes. An important step forward towards the elimination of the risk of blood-borne infections transmitted by plasma products was recently made through the application of virucidal methods to clotting factor concentrates. Since HIV appears more vulnerable to such methods than the hepatitis viruses, currently available concentrates can be considered substantially free from the risk of transmitting HIV infection. Even though transmission of hepatitis is much reduced but not totally abolished, virucidal methods are continuously being improved, so that it can be foreseen that concentrates will become safer and safer. Finally, factor VIII produced by recombinant DNA technology is undergoing the first clinical trials in hemophiliacs. Hopefully, it will free from the risk of transmitting infections and will be available in sufficiently large amounts to meet the need of hemophiliacs worldwide. In 1982, the World Federation of Hemophilia published a message on the status of diagnosis and treatment of hemophilia. Since then, hemophilia care has been complicated by widespread infection of hemophiliacs with human immunodeficiency virus (HIV).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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To investigate the interval between HIV-1 infection and the development of clinical AIDS among Italian patients with congenital coagulation disorders, a national cohort study was undertaken in 1988. Information was collected both retrospectively and prospectively on 499 HIV-1-positive patients enrolled in an ongoing national registry of patients with congenital coagulation disorders. Two methods were used to estimate each patient's seroconversion date: the mid-point between the last negative (either known or estimated) and the first positive test, and the median under a Weibull distribution, which was assumed to fit seroconversion data. The two methods of estimating the seroconversion time yielded similar results. The actuarial incidence of AIDS was estimated using the Kaplan-Meier survival analysis at 12.8% (95% confidence interval = 9.7-15.9) over 7 years for Italian haemophiliacs. Progression appears to be slow in the first 5 years after the infection, and to rise steadily thereafter. A strong association between faster progression and older age at seroconversion was found. Zidovudine-treated individuals seem to have a slower progression than untreated individuals, after controlling for CD4, but there was no association between progression and type and severity of the congenital disorder.  相似文献   
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Protein S activity in plasma from factor V Leiden (FVL)-positive patients may be lower than expected. We investigated a new commercially available method for protein S for such interference. Protein S activity was measured for plasmas from 50 individuals with FVL and their results were compared with those obtained for plasmas from 47 sex-matched and age-matched individuals without FVL. We assumed that the median protein S activity value from a relatively large number of individuals with or without FVL would not be significantly different if there is no influence from FVL. The FVL-positive plasmas gave relatively (albeit not significantly) lower protein S levels than FVL-negative plasmas when both were tested undiluted (86 versus 93 IU/dl, P = 0.06). Those differences were reduced (98 versus 102 IU/dl, P = 0.58) when testing was performed on diluted plasmas. Furthermore, the proportion of patients with FVL identified as low-abnormal on the basis of the specific cut-off values (undiluted = 64 U/dl; diluted = 71 IU/dl), which was 8% when testing was performed on undiluted plasmas, was reduced to 4% when testing was performed on diluted plasmas. Conversely, the corresponding proportions of patients without FVL remained unaltered (4.3 versus 4%). In conclusion, these results indicate that the evaluated method is somewhat affected by FVL and that dilution of plasma prior to testing improves specificity. Protein S activity measurement for FVL-positive patients should be performed on diluted plasma and the results interpreted on the basis of the cut-off value specifically determined for diluted plasmas.  相似文献   
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BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.  相似文献   
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