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1.
The human cytomegalovirus (HCMV) UL144 gene is a tumor necrosis factor-like receptor with the potential to affect HCMV virulence. HCMV strains display genetic variability in the UL144 region, and the analysis of a potential link between UL144 gene polymorphisms and disease severity has scarcely been studied. However, a correlation between the UL144 genotype and congenital-disease outcome has been reported in one previous study, with the observation that all asymptomatic infants had a single UL144 genotype. In order to confirm or refute this finding, we determined the UL144 polymorphisms of HCMV strains recovered from the amniotic fluids of 38 infected fetuses and compared them to HCMV strains obtained from 30 viremic adult controls. The UL144 sequences were distributed among five genotypes (A, B, C, AC, and AB), as previously described. We observed similar percentages of the three major genotypes A (37%), B (33%), and C (27%) in our population. The UL144 genotype distributions were similar among the group of infected adults and the group of infected fetuses and among symptomatic and asymptomatic fetuses (P < 0.05). In our series, all five UL144 genotypes could be vertically transmitted from mothers to fetuses, and all could cause symptomatic congenital infection. We concluded that determination of UL144 polymorphisms in cases of congenital infection is not relevant, since it is unlikely to help predict the outcome of the infection.  相似文献   
2.
Predictive factors of the virologic success of the use of lopinavir/ritonavir (LPV/r) in HIV-infected children are unknown, especially in children who have been pretreated with protease inhibitors (PIs). This longitudinal, single-center, observational study included 69 children (21 PI-naive and 48 PI-experienced) who had received LPV/r for at least 3 months. The mean (+/- SD) age was 10.3 +/- 4.8 years, and the mean baseline of CD4 percentage and HIV-1 RNA was 14.9% +/- 9.8% and 4.8 +/- 1.05 log10 copies/mL, respectively. The mean duration of follow-up was 16.5 +/- 8.3 months. At 6, 12, and 18 months, 52%, 57%, and 49% of all children, respectively, had a viral load less than 50 copies/mL. The risk of virologic failure, defined as 2 consecutive viral loads greater than 1000 copies/mL, was significantly higher when the children were previously treated with PIs and when the baseline LPV mutation score exceeded 3 mutations. In the pretreated children, the ratio of the plasma LPV maximal concentration to the baseline LPV score mutation was also associated with failure, independently of resistance score. Finally, in children failing an LPV-containing regimen, accumulation of additional PI-associated resistance mutations was evidenced in viral isolates from children with prior PI treatment, even with viral replication levels less than 10,000 copies/mL. In pretreated children, LPV plasma levels should be optimized in an attempt to achieve sufficient drug concentrations to overcome the resistance level.  相似文献   
3.
A 53-year-old-woman presenting with pelvic discomfort was found to have a 9.5 cm tumor located in the wall of the ileon. Light microscopy showed that the tumor was made of fascicles of plump spindle cells and bizarre epithelioid cells. A cuff of lymphoid cells was also present at the tumor margin. The tumor cells strongly expressed tau protein, neuron-specific enolase, protein green product 9.5 and glial fibrillary acid protein (GFAP), but did not show positive immunostaining for S-100 protein, CD34 or CD117. The tumor showed unequivocal ultrastructural evidence of neural differentiation. Skeinoid fibers were scattered throughout the tumor. This is the first mixed neuronal-glial tumor of the digestive tract to be described in the literature. Such histological and immunohistochemical features could be misinterpreted as features of digestive schwannoma. We suggest that this tumor is distinct from gastrointestinal stromal tumors in lacking CD34 and CD117 expression.  相似文献   
4.
 Poly(ADP-ribosyl)ation is a posttranslational modification of nuclear proteins which is catalyzed by poly(ADP-ribose) polymerase and represents an immediate response of eukaryotic cells to oxidative and other types of DNA damage. Previously a strong correlation had been detected between maximal poly(ADP-ribose) polymerase activity in permeabilized mononuclear leukocytes of various mammalian species and species-specific life span. To study a possible relation between longevity and poly(ADP-ribosyl)ation in humans we measured maximal oligonucleotide-stimulated poly(ADP-ribose) polymerase activity in permeabilized, Epstein-Barr virus transformed lymphoblastoid cell lines from a French population of 49 centenarians and 51 controls aged 20–70 years. Maximal enzyme activity was significantly higher in centenarians than in controls [median of controls: 9035 cpm/106 cells (lower quartile: 6156; upper quartile: 11,410); median of centenarians: 10,380 cpm/106 cells (lower quartile: 7994; upper quartile: 12,991); P=0.031 by Mann-Whitney U test]. In a subset of 16 controls and 24 centenarians, cellular poly(ADP-ribose) polymerase content was determined by quantitative western blotting, thus allowing the calculation of specific enzyme activity. The latter was significantly higher in centenarians (P=0.006), the median value for centenarians being about 1.6-fold that of controls. Specific poly(ADP-ribose) polymerase activity was a more powerful parameter for differentiating between centenarians and controls than enzyme activity relative to cell number. In addition, in a genetic association study we analyzed 437 DNA samples (239 centenarians and 198 controls) by PCR amplification of a polymorphic dinucleotide repeat located in the promoter region of the poly(ADP-ribose) polymerase gene in an attempt to detect an association between this polymorphic marker and variability of enzyme activity or human longevity. However, this genetic analysis revealed no significant enrichment of any of the alleles or genotypes identified among centenarians or controls, but its power was limited by the relatively weak hetero-zygosity of this polymorphic marker in our population (51%). Viewed together with previous results on poly(ADP-ribose) polymerase activity in various mammalian species, the present data provide further evidence for the notion that longevity is associated with a high poly(ADP-ribosyl)ation capacity. Received: 5 September 1997 / Accepted: 10 November 1997  相似文献   
5.
Bone vascular tumors are very rare. Epithelioid types are described according to their architecture, their degree of vascular differentiation, and their cytonuclear atypia. The include epithelioid hemangioma, epithelioid hemangioendothelioma, and angiosarcoma. We report a case of L4 corpus vertebral bone epithelioid hemangioma. The patient was a 25-year-old man with a tumor that recurred twice. The lesion was characterized by a vascular lumen lined by cells with regular nuclei and inflammatory infiltrates. Capillaries were lined by prominent epithelioid endothelial cells, associated with CD31+ and cytokeratin-.  相似文献   
6.
7.
OBJECTIVES: Congenital Cytomegalovirus (CMV) infection is the main cause of neurological handicap in young children. The objective for studying genetic polymorphism of strains responsible for congenital infection is to identify CMV strains or groups of strains which would be more frequent in this context and/or which would be responsible for more severe congenital infection. METHODS: In this paper, we report and analyze the literature concerning the genetic polymorphism of CMV strains responsible of congenital infection, in the genes coding for the envelop protein B and the non structural UL144 protein and in the CMV short tandem repeats. RESULTS AND CONCLUSION: All UL144 and gB genotypes can be vertically transmitted from mothers to fetuses, none of these studies has shown any link between the genotypes and the severity of congenital disease. Moreover, no link between short tandem repeats polymorphism and severity of congenital disease has been demonstrated. However, short tandem repeats analysis may be a powerful tool to study the epidemiology of CMV congenital infections.  相似文献   
8.
9.
The objective of this study was to evaluate the pharmacokinetic response to intravenous (IV) enoxaparin given 8-12 hr after subcutaneous (SC) dosing in patients undergoing percutaneous coronary intervention (PCI). Fifty-five patients received SC enoxaparin (1 mg/kg every 12 hr) followed by an IV bolus (0.3 mg/kg) 8-12 hr after the last SC dose, at the start of PCI or during catheterization. Anti-Xa levels were within the target range in 98% of patients 2-8 hr after the last SC dose, in 96% of patients following the IV bolus, and in 91% of patients for a further 2 hr. Subcutaneous enoxaparin (1 mg/kg every 12 hr) provides sufficient anti-Xa levels for PCI 2-8 hr after the last dose. An additional 0.3 mg/kg enoxaparin dose given IV 8-12 hr after the last SC dose reliably maintains anti-Xa levels within the target for at least 2 additional hr.  相似文献   
10.
A prerequisite to dephosphorylation at Ser–Pro or Thr–Pro motifs is the isomerization of the imidic peptide bond preceding the proline. The peptidyl-prolyl cis/trans isomerase named Pin1 catalyzes this mechanism. Through isomerization, Pin1 regulates the function of a growing number of targets including the microtubule-associated tau protein and is supposed to be deregulated Alzheimer's disease (AD). Using proteomics, we showed that Pin1 is posttranslationally modified on more than 5 residues, comprising phosphorylation, N-acetylation, and oxidation. Although Pin1 expression remained constant, Pin1 posttranslational two-dimensional pattern was modified by tau overexpression in a tau-inducible neuroblastoma cell line, in our THY-Tau22 mouse model of tauopathy as well as in AD. Interestingly, in all of these systems, Pin1 modifications were very similar. In AD brain tissue when compared with control, Pin1 is hyperphosphorylated at serine 16 and found in the most insoluble hyperphosphorylated tau fraction of AD brain tissue. Furthermore, in all tau pathology conditions, acetylation of Pin1 may also contribute to the differences observed. In conclusion, Pin1 displays several posttranslational modifications, which are specific in tauopathies and may be useful as biomarker.  相似文献   
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