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991.
Varicella is a common viral disease affecting almost the entire birth cohort. Although usually self-limiting, some cases of varicella can be serious, with 2 to 6% of cases attending a general practice resulting in complications. The hospitalisation rate for varicella in Europe ranges from 1.3 to 4.5 per 100,000 population/year and up to 10.1% of hospitalised patients report permanent or possible permanent sequelae (for example, scarring or ataxia). However, in many countries the epidemiology of varicella remains largely unknown or incomplete. In countries where routine childhood vaccination against varicella has been implemented, it has had a positive effect on disease prevention and control. Furthermore, mathematical models indicate that this intervention strategy may provide economic benefits for the individual and society. Despite this evidence and recommendations for varicella vaccination by official bodies such as the World Health Organization, and scientific experts in the field, the majority of European countries (with the exception of Germany and Greece) have delayed decisions on implementation of routine childhood varicella vaccination, choosing instead to vaccinate high-risk groups or not to vaccinate at all. In this paper, members of the Working Against Varicella in Europe group consider the practicalities of introducing routine childhood varicella vaccination in Europe, discussing the benefits and challenges of different vaccination options (vaccination vs. no vaccination, routine vaccination of infants vs. vaccination of susceptible adolescents or adults, two doses vs. one dose of varicella vaccine, monovalent varicella vaccines vs. tetravalent measles, mumps, rubella and varicella vaccines, as well as the optimal interval between two doses of measles, mumps, rubella and varicella vaccines). Assessment of the epidemiology of varicella in Europe and evidence for the effectiveness of varicella vaccination provides support for routine childhood programmes in Europe. Although European countries are faced with challenges or uncertainties that may have delayed implementation of a childhood vaccination programme, many of these concerns remain hypothetical and with new opportunities offered by combined measles, mumps, rubella and varicella vaccines, reassessment may be timely.  相似文献   
992.
993.
Epstein-Barr virus (EBV)-related post-transplantation lymphoproliferative disorder (PTLD) is a life-threatening complication in patients given T-cell-depleted hematopoietic stem cell transplantation from an HLA-haploidentical relative (haplo-HSCT). We report the case of a child who developed severe EBV-related PTLD after haplo-HSCT from his mother. Despite receiving the anti-CD20 monoclonal antibody, the patient presented with intestinal obstruction due to huge abdominal lymphadenopathy, hematemesis, and nodulary pulmonary lesions. Histology showed that the lesions were due to CD20-/CD19+ large neoplastic B cells. The patient underwent double intestinal resection with partial abdominal lymphadenectomy and then received 3 monthly doses of donor-derived unmanipulated mononuclear cells. The initial dose of CD3+ cells was 3?10(5)/kg recipient body weight. The 2 additional doses consisted of 5?10(5) CD3+ cells/kg. No sign or symptom attributable to graft-versus-host disease was observed, and the patient completely cleared EBV-related lesions. The child was disease-free for 13 months after the first lymphocyte infusion. This case demonstrates that repeated infusions of controlled numbers of donor CD3+ cells cure EBV-related PTLD in haplo-HSCT without inducing graft-versus-host disease.  相似文献   
994.
Aim: To assess the development of preterm infants from 40 weeks gestational age to 18 months corrected age to identify early predictors of later development. Methods: Fifty‐one infants were involved. Infant development was assessed at 40 and 44 weeks gestational age with the Brazelton neonatal behavioral assessment scale and a self‐regulation scale and at 3, 6, 10, 18 months corrected age with the Bayley Scales of Infant Development. The quality of general movements was assessed at 1 and 3 months corrected age and maternal attachment style at infant’s age of 6 months corrected age with the Relation Scale Questionnaire. Results: At term age and 1‐month corrected age, preterm infants were less mature and had lower levels of self‐regulation than full‐term infants. At 3 months corrected age, a higher proportion of preterm infants (43%) had mildly abnormal motor quality compared to the general population (25%). At all follow‐ups, preterm infants had delayed mental, motor and behavioural development, which was associated with the level of self‐regulation, motor quality and maternal attachment style. Maternal education level was the most predominant background factor related to infant development. Conclusion: Preterm infants show early‐in‐life deviations in self‐regulation, motor quality and development. These deviations are risk factors for later optimal functioning.  相似文献   
995.
T-cell differentiation and induction of tolerance to self-antigens occurs mainly in the thymus. Thymic stromal cells, specifically medullary thymic epithelial cells, express a diverse set of genes encoding parenchymal organ-specific proteins. This phenomenon has been termed promiscuous gene expression (PGE) and has been implicated in preventing organ-specific autoimmunity by inducing T-cell tolerance to self antigens. Early thymopoiesis and the critical factors involved in T-cell differentiation can be reproduced in vitro by murine fetal thymus organ culture (FTOC), which mimics the natural thymic microenvironment. To evaluate the occurrence of PGE in FTOC, gene expression profiling during in vitro thymic development in BALB/c mice was performed using a set of nylon cDNA microarrays containing 9216 sequences. The statistical analysis of the microarray data (sam program) revealed the temporal repression and induction of 57 parenchymal and seven lymphoid organ-specific genes. Most of the genes analysed are repressed during early thymic development (15-17 days post-coitum). The expression of the autoimmune regulator (AIRE) gene at 16 days post-coitum marks the onset of PGE. This precedes the induction of parenchymal organ genes during the late developmental phase at 20 days post-coitum. The mechanism of T-cell tolerance induction begins during fetal development and continues into adulthood. Our findings are significant because they show a fine demarcation of PGE onset, which plays a central role in induction of T-cell tolerance.  相似文献   
996.
OBJECTIVE: To study trends in progression to AIDS, all-cause mortality, and cause-specific mortality (AIDS-related, liver disease, and hemorrhagic complications) over calendar periods with different exposure to highly active antiretroviral therapy (HAART) in a cohort of hemophiliacs in Spain, taking into account the competing risks of the causes of death. METHODS: Multicenter cohort of HIV-infected hemophiliacs. HIV seroconversion was estimated using mathematic techniques for interval-censored data from 1979 through 1985. Rates of AIDS and cause-specific death were calculated by Poisson regression, allowing for late entry, for the periods 1985 through 1992, 1993 through 1996, 1997 through 2000 (early HAART), and 2001 through 2003 (late HAART), also allowing for competing risks. RESULTS: Of 585 subjects, 44% were younger than 15 years of age, 82% had severe hemophilia, 86% had type A hemophilia, and the median seroconversion date was October 1982. Calendar period and age at HIV seroconversion strongly influenced AIDS and death rates. Compared with 1993 through 1996, decreases of 75% (relative risk [RR] = 0.25, 95% confidence interval [CI]: 0.14 to 0.43) and 72% (RR = 0.28, 95% CI: 0.12 to 0.63) in the RR of AIDS were observed in early and late HAART. For all-cause mortality, 72% (RR = 0.28, 95% CI: 0.18 to 0.42) and 83% (RR = 0.17, 95% CI: 0.09 to 0.33) decreases were observed by 1997 through 2000 and 2001 through 2003. For liver-related deaths, increases were observed in the late-HAART period (RR = 2.80, 95% CI: 0.94 to 8.36) compared with 1993 through 1996, but using competing risks, this RR was substantially reduced (RR = 1.70, 95% CI: 0.57 to 5.04). DISCUSSION: Major reductions in AIDS and death rates were observed from 1997 to 2003 in hemophiliacs. These survival improvements are largely attributable to decreases in AIDS-related deaths and have been accompanied by increases in liver disease death rates, which are overestimated if competing risks are not taken into account.  相似文献   
997.
Esculetin is a polyphenolic compound with cytoprotective properties. We previously demonstrated the induction of apoptosis by esculetin in NB4 human leukemia cells, as a model, by a mechanism not well understood. To analyse the antioxidant activity of esculetin on apoptosis, we have studied the influence of co-treatments of esculetin at a concentration of 100 μM with exogenous ROS donors, namely tert-butyl-hydroperoxide and hydrogen peroxide, on NB4 cells. Esculetin (100 μM) exerts a protective effect on cell viability and death necrosis or late apoptosis caused by the oxidant t-BHP whereas it potentiates decrease of cell viability and cell death caused by H2O2. In the first case, the O2? scavenging activity of esculetin (100 μM) could be implicated. In the last one, cytotoxicity by apoptosis induction seems to be related to the increase in O2?, among other possible mechanisms. These results contribute to the study of the antitumor properties of esculetin by regulation of redox balance in leukemia cells.  相似文献   
998.
The successful clinical application of materials should involve detailed investigations on interaction between them and tissue with which they will contact. We examined herein the behavior of endothelial cells (ECs) on a collagen material, using histological and immunohistochemical methods. We used isolated human umbilical cord vein cells (HUVECs) identified by means of endothelial-specific antibodies. Cells were seeded in a standard density on a collagen membrane (Lycoll, Resorba, Nuernberg, Germany) and on gelatin-coated, control plastic surfaces, after two passages. These were then maintained for periods of 1, 7, or 14 days. The cells adhered, spread, and proliferated, and within 24 h started forming a subconfluent monolayer. We observed that the cultured cells expressed integrins (alpha5beta1 and alpha(v)beta3) and synthesized fibronectin. After 14 days, we could observe a confluent layer of ECs. We could conclude that the collagen material supported growth and attachment of endothelial cells. In addition, the attachment seemed to be most related to the fibronectin synthesized by the cells and to its highly expressed receptor (the alpha5beta1 integrin); even though this is not the only protein related to this adhesion, we observed that our cultured HUVECs did not synthesize vitronectin.  相似文献   
999.
The heavy-chain variable regions (VH) from 14F7 MAb, an IgG1 antibody specific for GM3(NeuGc) ganglioside, and its anti-idiotype, the 4G9 MAb, were cloned and sequenced. Comparison with previously reported sequences showed that VH 14F7 belongs to the J558(VHI) gene family and that it is highly mutated. VH 4G9 belongs to the Q52(VHII) gene family. The HCDR3 14F7 sequence contains three basic residues that could be involved in the binding to 4G9 MAb, which bears acidic residues in its HCDR3. Studies performed in the syngeneic model showed that 14F7 MAb requires both coupling to KLH and the use of Freund's adjuvant to induce an effective anti-idiotypic IgG (Ab2) response. In contrast, P3 MAb, a germline gene-encoded Ab1 that also recognizes the GM3(NeuGc) ganglioside through a basic motif in its H-CDRs, has been reported to be immunogenic in syngeneic mice, even when injected in saline. In addition, when Leghorn chickens were immunized with 14F7 or P3 MAbs emulsified in Freund's adjuvant, only P3-immunized animals were able to develop antibodies that recognized NeuGc-containing gangliosides, antigens which are not present in the normal tissues of this animal species. This phenomenon could be due to the lack of idiotypic connectivity of 14F7MAb.  相似文献   
1000.
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