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An outbreak of infection with hepatitis A virus associated with a foodhandler and involving 26 subjects occurred in Southern Italy. Sequence analysis of the VP3-VP1 and VP1-P2A junctions confirmed that the outbreak was due to a point source and allowed the identification of a new genotype IB variant. This report confirms the usefulness of sequence-based molecular fingerprinting during outbreaks.  相似文献   
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Di Rosa F  Santoni A 《Immunology》2003,108(3):296-304
The presence in the bone marrow of memory CD8 T cells is well recognized. However, it is still largely unclear how T-cell migration from the lymphoid periphery to the bone marrow is regulated. In the present report, we show that antigen-specific CD4 T cells, as well as antigen-specific CD8 T cells, localize to the bone marrow of immunized mice, and are sustained there over long periods of time. To investigate the rules governing T-cell migration to the bone marrow, we generated chimeric mice in which the lymphoid periphery contained two genetically or phenotypically distinct groups of T cells, one of which was identical to the host. We then examined whether a distinct type of T cell had an advantage over the others in the colonization of bone marrow. Our results show that whereas ICAM1 and CD18 molecules are both involved in homing to lymph nodes, neither is crucial for T-cell bone marrow colonization. We also observed that memory-phenotype CD44high T cells, but not virgin-type CD44-/low T cells, preferentially home to the bone marrow upon adoptive transfer to normal young mice, but not to thymectomized old recipients where an existing memory T-cell pool precludes their free access. Thus, T-cell colonization of the bone marrow uses distinct molecules from those implicated in lymph node homing, and is regulated both by the properties of the T cell and by the competitive efficacy of other T cells inhabiting the same, saturable niche. This implies that the homing potential of an individual lymphocyte is not merely an intrinsic property of the cell, but rather a property of the lymphoid system taken as a whole.  相似文献   
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We report a case of osteomyelitis caused by Enterobacter cancerogenus resistant to aminopenicillins in a 56-year-old male who had a motorcycle accident and suffered from multiple bone fractures with abundant environmental exposure. E. cancerogenus has rarely been associated with human infections, and its clinical significance remains unclear.  相似文献   
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Several circulating Bacillus anthracis strains isolated in Italy and belonging to the A1.a cluster, genotype 3 (A1.a-3) are genotypically indistinguishable from Carbosap, a live attenuated vaccine strain, containing both pXO1 and pXO2 plasmids. The genotype was assessed by using eight-locus multilocus variable-number tandem repeat analysis. We describe here the use of a ninth locus able to explore variability among strains that have the same genotype. It is important to be able to genotype the wild isolate of B. anthracis strains from outbreaks of anthrax in areas where Carbosap vaccination of cattle and sheep is common practice. A total of 27 representative field strains isolated in Italy and four vaccinal strains, namely, Carbosap, Sterne, Pasteur I, and Pasteur II, were characterized by a ninth marker, called pXO2-A. Twenty-three field strains were genotype 3 and therefore identical to Carbosap. The marker was in the pXO2 plasmid and is based on the polymorphism of the already-known VX2-3 locus. Detection was obtained by PCR with fluorescence-labeled forward primers in order to produce appropriate fragments for capillary electrophoresis with an ABI 310 genetic analyzer. Genetic relationships showed heterogeneity in all of the examined samples. Interestingly, with respect to genotype 3, samples grouped into eight different subtypes, A to H, and the subtype G, had only two samples indistinguishable from Carbosap. The results of the present study confirm the validity of a hierarchical progressive protocol for discrimination among closely related isolates.  相似文献   
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Neuregulin 1 (NRG1) is one of the most exciting candidate genes for schizophrenia since its first association with the disorder in an Icelandic population. Since then, many studies have analyzed allele and haplotype frequencies in European and Asian populations in cases and controls yielding varying results. We investigated the association of NRG1 with psychosis in a total sample set of 575 individuals from 151 Spanish nuclear families. We tested eight SNPs across 1.2 Mb along NRG1 including regions previously associated to schizophrenia in association studies. After correction for multiple testing, the TDT analysis for each marker did not show a significant over-transmission of alleles from the parents to the affected offspring for any of the markers (P > 0.05). The haplotypic analysis with TRANSMIT and PDT did not show preferential transmission for any of the haplotypes analyzed in our sample. These results do not seem to suggest that the investigated NRG1 markers play a role in schizophrenia in the Spanish population, although the finding of a trend for association with one SNP in the 3'of the gene warrants further investigation.  相似文献   
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BACKGROUND: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). METHODS: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. RESULTS: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. CONCLUSIONS: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy.  相似文献   
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