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OBJECTIVES: To evaluate the benefit of fluconazole prophylaxis in preventing invasive fungal infection in very low birth weight (VLBW) infants with central vascular access. STUDY DESIGN: A 3-year baseline period (1998 to 2000) was compared with a subsequent 3-year period (2001 to 2003) during which a different protocol for preventing invasive fungal infection was used. All infants with a birth weight < 1500 g and with central vascular access were eligible for the study. Fluconazole (Diflucan R) was administered for 28 days at a dose of 6 mg/kg every third day during the first week and daily after the first week. RESULTS: There were no significant differences between the baseline and the fluconazole groups in demographic characteristics or risk factors for fungal infection. Fungal infection developed in 9 of the infants in the baseline group and in none of those in the fluconazole group (P=.003). A trend of decreasing mortality rate between the 2 groups (12.6% vs 8.1%; P=.32) was observed but was not statistically significant. No adverse effects of fluconazole therapy were documented. CONCLUSIONS: Fluconazole prophylaxis appeared to be beneficial in preventing invasive fungal infection in VLBW infants.  相似文献   
174.
Spinal muscular atrophy (SMA) is caused by insufficient levels of survival motor neuron (SMN) protein. Recently, we found that sodium 4-phenylbutyrate (PB), a well-tolerated FDA approved drug, enhances SMN gene expression in vitro. We provide here the first evidence that oral administration of PB (triButyrate significantly increases SMN expression in leukocytes of SMA patients. This finding provides a strong rationale to further investigate the effects of PB as also supported by preliminary clinical data.  相似文献   
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Little is known about prokaryotic homologs of Cu,Zn superoxide dismutase (SOD), an enzyme highly conserved among eukaryotic species. In 138 Archaea and Bacteria genomes, 57 of these putative homologs were found, 11 of which lack at least one of the metal ligands. Both the solution and the crystal structures of the SOD-like protein from Bacillus subtilis, lacking two Cu ligands and found to be enzymatically inactive, were determined. In solution, the protein is monomeric. The available nuclear Overhauser effects, together with chemical-shift index values, allowed us to define and to recognize the typical Cu,Zn SOD Greek beta-barrel but with largely unstructured loops (which, therefore, sample a wide range of conformations). On the contrary, in the crystal structure (obtained in the presence of slight excess of Zn), the protein is well structured and organized in covalent dimers held by a symmetric bridge consisting of a Zn ion bound to an Asp-His dyad in a tetrahedral geometry. Couples of dimers held by hydrophobic interactions and H bonds are further organized in long chains. The order/disorder transition is discussed in terms of metal binding and physical state.  相似文献   
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Recombinant human nerve growth factor (rhNGF) is regarded as the most promising therapy for neurodegeneration of the central and peripheral nervous systems as well as for several other pathological conditions involving the immune system. However, rhNGF is not commercially available as a drug. In this work, we provide data about the production on a laboratory scale of large amounts of a rhNGF that was shown to possess in vivo biochemical, morphological, and pharmacological effects that are comparable with the murine NGF (mNGF), with no apparent side effects, such as allodynia. Our rhNGF was produced by using conventional recombinant DNA technologies combined with a biotechnological approach for high-density culture of mammalian cells, which yielded a production of approximately 21.5 +/- 2.9 mg/liter recombinant protein. The rhNGF-producing cells were thoroughly characterized, and the purified rhNGF was shown to possess a specific activity comparable with that of the 2.5S mNGF by means of biochemical, immunological, and morphological in vitro studies. This work describes the production on a laboratory scale of high levels of a rhNGF with in vitro and, more important, in vivo biological activity equivalent to the native murine protein.  相似文献   
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In this study, we characterized five Ullrich scleroatonic muscular dystrophy patients (two Italians, one Belgian, and two Turks) with a clinical phenotype showing different degrees of severity, all carrying mutations localized in COL6A1. We sequenced the three entire COL6 complementary DNA. Three of five patients have recessive mutations: two patients (P1and P3) have homozygous single-nucleotide deletions, one in exon 9 and one in exon 22; one patient (P2) has a homozygous single-nucleotide substitution leading to a premature termination codon in exon 31. The nonsense mutation of P2 also causes a partial skipping of exon 31 with the formation of a premature termination codon in exon 32 in 15% of the total COL6A1 messenger RNA. The remaining two patients carry a heterozygous glycine substitution in exons 9 and 10 inside the triple-helix region; both are dominant mutations because the missense mutations are absent in the DNA of their respective parents. As for the three homozygous recessive mutations, the apparently healthy consanguineous parents all carry a heterozygous mutated allele. Here, for the first time, we report a genotype-phenotype correlation demonstrating that heterozygous glycine substitutions in the triple-helix domain of COL6A1 are dominant and responsible for a milder Ullrich scleroatonic muscular dystrophy phenotype, and that recessive mutations in COL6A1 correlate with more severe clinical and biochemical Ullrich scleroatonic muscular dystrophy phenotypes.  相似文献   
178.
We report a 6-year-old girl in whom Mycoplasma pneumoniae infection presenting with erythema multiforme, multiorgan, and hematologic dysfunctions induced a long-standing, marked B-cell lymphopenia. An increase of CD8+ lymphocytes was also detected. We suggest that a selective cytotoxic T lymphocyte-dependent B cell lysis and the expansion of super-antigen activated CD8+ T cells may account for the multiorgan and hematologic disturbances triggered by M. pneumoniae.  相似文献   
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