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Vincenzo De Giorgi  MD    Daniela Massi  MD    Elisa Trez  MD    Camilla Salvini  MD    Elena Quercioli  MD    Paolo Carli  MD 《Dermatologic surgery》2003,29(9):965-967
In dermoscopy, the correct recognition of the single parameters is fundamental to achieve great diagnostic accuracy, but the scarce morphologic expression of a parameter may lead to diagnostic errors. We report the case of a 27-year-old white man presenting a pigmented lesion of the back, which was present since puberty. Clinical examination revealed on the back the presence of a flat, gray-blue lesion and at the periphery a small dark-brown papule. An assessment of the lesion by means of dermoscopy was performed. The purpose of this report was to analyze the Blue Hue in dermoscopy with its histopathologic correlates, starting with the discussion of a clinical case.  相似文献   
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Summary An epidemiological survey of hereditary ataxias and paraplegias was conducted in Molise, a region of Italy (335, 211 inhabitants on 1 January 1989). Total prevalence was 7.5 x 10–5 inhabitants (95% confidence limits 4.8–11.1). There were 7 patients with Friedreich's disease, 5 with early onset cerebellar ataxia with retained tendon reflexes, 4 with ataxia-telangiectasia, 9 with hereditary spastic paraplegias (2 autosomal dominant and 7 autosomal recessive cases). There was no patient with autosomal dominant cerebellar ataxia.  相似文献   
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Patients with agammaglobulinemia may excrete enteroviruses, including vaccine-derived poliovirus, for prolonged periods of time. This poses a risk to the patients but it also may pose a risk to the population after eradication of poliovirus and the cessation of routine vaccination. To assess this risk, a pilot study was performed to identify potential poliovirus long-term excretors in a cohort of 38 patients with a definite/presumptive diagnosis of X-linked agammaglobulinemia (XLA). Stool samples were analyzed to detect any polio or other enteroviruses replicating in the gut and neutralizing antibodies against polioviruses were measured in the sera. No viruses were isolated from the stool samples and most sera had neutralizing antibody levels against all three poliovirus serotypes considered by the WHO to be protective in immunocompetent individuals. This suggests that long-term excretion of enteroviruses in patients with agammaglobulinemia is relatively uncommon.  相似文献   
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Homozygous (Δccr5/Δccr5) and heterozygous (CCR5/Δccr5) deletions in the β-chemokine receptor 5 (CCR5) gene, which encodes for the major co-receptor for macrophage-tropic HIV-1 entry, have been implicated in resistance to HIV infection and in protection against disease progression, respectively. The CCR5/Δccr5 genotype was found more frequently in long-term nonprogressors (LTNP) (31.0%) than in progressors (10.6%, p < 0.0001), in agreement with previous studies. Kaplan-Meier survival analyses showed that a slower progression of disease, i.e. higher proportion of subjects with CD4+ T cell counts >500/μl (p = 0.0006) and a trend toward a slower progression to AIDS (p = 0.077), was associated with the CCR5/Δccr5 genotype. However, when LTNP were analyzed separetely, no significant differences in CD4+ T cell counts (p = 0.12) and viremia levels (p = 0.65) were observed between the wild-type (69 % of LTNP) and the heterozygous (31.0 %) genotypes. Therefore, there are other factors which play a major role in determining the status of nonprogression in the majority of LTNP. Furthermore, there was no evidence that the CCR5/Δccr5 genotype was associated with different rates of disease progression in the group of progressors. Taken together, these results indicate that the CCR5/Δccr5 genotype is neither essential nor sufficient for protection against the progression of HIV disease.  相似文献   
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Clericuzio-type poikiloderma with neutropenia is a well-defined nosological entity, but despite a remarkable number of clinical reports, no long term follow-up data has been presented to date regarding patients with this rare condition.Here we describe the results of clinical follow-up of three siblings, one male (Patient 1) and two females (Patients 2 and 3), subsequent to their first clinical and then molecular diagnosis of Clericuzio-type poikiloderma with neutropenia syndrome due to mutation of USB1gene. Patient 1 always expressed the most severe phenotype, while patients 2 and 3 showed an intermediate and mild phenotype, respectively, as observed since their first clinical evaluation. None of the patients developed skin cancer and/or myelodysplastic disorders considering the peripheral haematological findings. Lens opacity, never reported before, was found in two of the three patients.The long term follow-up observations confirm the stability over time of the pronounced intra-familial heterogeneity of clinical manifestations observed prior to and upon molecular diagnosis. We conclude that prolonged follow-up is an adjunct tool to monitor intra-familial variability of PN clinical spectrum which may favour surveillance of more serious complications of the disease among siblings, when a patient-specific clinical expressivity is present.  相似文献   
17.
Germ-line mutations in the BRCA1 gene cause hereditary predisposition to breast and ovarian cancer. BRCA1 and BRCA2 mutations account for about 40% of high-risk families. Mutation-screening methods generally focus on genomic DNA and are usually PCR based; they enable the detection of sequence alterations such as point mutations and small deletions and insertions. However, they do not allow the detection of partial or entire exon(s) loss, because the presence of the homologous allele results in a positive PCR signal, giving rise to a false-negative result. Identification of unusual haplotypes in patient samples by an expectation maximization algorithm has recently been suggested as a method for identifying hemizygous regions caused by large intragenic deletions. Using a similar approach, we identified a novel BRCA1 genomic rearrangement in a breast/ovarian cancer family negative at the first mutation screening; we detected a deletion encompassing exons 14-19, probably due to replication slippage between Alu sequences.  相似文献   
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Evolution of foot-and-mouth disease virus   总被引:28,自引:0,他引:28  
Foot-and-mouth disease virus evolution is strongly influenced by high mutation rates and a quasispecies dynamics. Mutant swarms are subjected to positive selection, negative selection and random drift of genomes. Adaptation is the result of selective amplification of subpopulations of genomes. The extent of adaptation to a given environment is quantified by a relative fitness value. Fitness values depend on the virus and its physical and biological environment. Generally, infections involving large population passages result in fitness gain and population bottlenecks lead to fitness loss. Very different types of mutations tend to accumulate in the foot-and-mouth disease virus (FMDV) genome depending on the virus population size during replication. Quasispecies dynamics predict higher probability of success of antiviral strategies based on multivalent vaccines and combination therapy, and this has been supported by clinical and veterinary practice. Quasispecies suggest also new antiviral strategies based on virus entry into error catastrophe, and such procedures are under investigation. Studies with FMDV have contributed to the understanding of quasispecies dynamics and some of its biological implications.  相似文献   
20.
Transport of folates in mammalian cells occurs by a carrier-mediated mechanism. The human folate carrier (RFC-1) gene has been isolated and characterized. Within this gene, a common polymorphism, 80A-->G, changing a histidine to an arginine in exon 2 (H27R), was recently identified. Defects in folate metabolism, such as defective carrier molecules, could be implicated in the etiology of neural tube defects (NTDs). In the present case-control study, we recruited 174 Italian probands with nonsyndromic NTD, 43 mothers, 53 fathers and 156 control individuals and evaluated the impact of RFC-1 variant on NTD risk. A statistically significant risk was calculated for the 80GG genotype of the NTD cases (OR=2.35; 95% CI 1.21-4.58) and mothers (OR=2.74; 95% CI 0.92-8.38). On the contrary, the heterozygous genotype of the mothers and both heterozygous and homozygous genotypes of the fathers did not seem to be significant NTD risk factors. Furthemore, according to the multifactorial inheritance of NTDs, we demonstrated that the combined genotypes for MTHFR 1298A-->C and RFC-1 80A-->G polymorphisms of cases resulted in greater NTD risk than heterozygosity or homozygosity for RFC-1 80A-->G variant alone. Conversely, our data provide no evidence for an association between NTD phenotype and combined MTHFR C677T/RFC-1 A80G genotypes. Moreover, here we describe the combinations of the two MTHFR polymorphic sites (677CT and 1298AC) with RFC-1 genotypes. We found that both patients and controls could have at most quadruple-mutation combinations. Interestingly, 27% (7/26) of the mothers and 18.75% (30/160) of the cases genotyped presented four mutant alleles in comparison with 8.5% (11/129) of the controls. Finally, the frequency of NTD cases and mothers carrying combined heterozygosity for the two MTHFR polymorphisms and RFC-1 80GG homozygosity (677CT/1298AC/80GG) (cases=11.3%; mothers 11.5%) was increased compared with controls (1.6%). Altogether, our findings support the hypothesis that RFC-1 A80G variant may contribute to NTD susceptibility in the Italian population.  相似文献   
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