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1.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease.  相似文献   
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Little is known about the role of peripheral blood mononuclear cells (PBMCs) in lipopolysaccharide (LPS) elimination. We studied the endotoxin elimination capacities (EEC) of PBMCs of 15 healthy volunteers, 13 patients with sepsis, and 1 patient suffering from paroxysmal nocturnal hemoglobinuria (PNH). Although expression of CD14, the best-characterized receptor for LPS to date, was reduced from 93.6% ± 0.8% in healthy subjects to 50.5% ± 6.5% in patients with sepsis and was 0.3% in a patient with septic PNH, EEC were found to be unchanged. There was no difference in the amount of tumor necrosis factor alpha (TNF-α) released by PBMCs of healthy donors and patients with sepsis. Anti-CD14 antibodies (MEM-18) completely suppressed EEC, binding of fluorescein isothiocyanate-labeled LPS to monocytes as determined by FACScan analysis, and TNF-α release in all three groups studied. The concentrations of soluble CD14 (sCD14) secreted by endotoxin-stimulated PBMCs from healthy donors and patients with sepsis amounted to 4.5 ± 0.4 and 20.1 ± 1.8 ng/ml, respectively. Based on our results, we suggest that PBMCs eliminate LPS by at least two different mechanisms; in healthy subjects, the membrane CD14 (mCD14) receptor is the most important factor for LPS elimination, while in patients with sepsis (including the septic state of PNH), increased sCD14 participates in LPS elimination. Secretion of sCD14 is strongly enhanced under conditions of low expression of mCD14 in order to counteract the reduction of mCD14 and maintain the function of monocytes. This sCD14 may substitute the role of mCD14 in LPS elimination during sepsis. The elimination of LPS by PBMCs correlates with the binding reaction and the secretion of TNF-α.  相似文献   
4.
Gains of 13q are correlated with a poor prognosis in liposarcoma.   总被引:2,自引:0,他引:2  
Liposarcomas are a phenotypical heterogeneous group of tumors divided into four main subtypes: well-differentiated, dedifferentiated, myxoid/round cell, and pleomorphic. The aim of this study was to compare DNA sequence copy number changes of these subtypes as investigated by comparative genomic hybridization in 36 patients. Comparative genomic hybridization revealed genomic imbalances in tumors of 27 patients (mean 5.6 imbalances per tumor). The most frequent gains were within single regions of 1q, 12q, and 13q. We found a significant correlation of poor overall survival and gain of 13q21 (P=0.0221), 13q22 (P=0.0341), 13q31 (P=0.0410), and 13q32 (P=0.0074). The univariate Cox regression analysis revealed an increased risk of tumor-related death for patients whose liposarcomas possess with gains of 13q21 and 13q32 simultaneously (P=0.010; RR=7.1; 95% CI 1.6-31.7). Furthermore, 12 high-level amplifications were found in tumors of seven patients. In four cases 12q14-q15 and in two cases 13q32-q33 were amplified. We identified in different liposarcoma subtypes characteristic genomic changes: Gains and high-level amplifications of 12q occurred in all 11 investigated well-differentiated liposarcomas, and these changes were often present simultaneously with gains of 1q (mean 5.5 changes). In the two dedifferentiated liposarcomas, gains of 1q in both liposarcomas, and a high-level amplification of 13q were striking. Only eight of the 17 patients with myxoid/round cell liposarcomas showed changes in DNA copy number (mean 3.4 imbalances). In four of these eight cases gains of 13q occurred. The six pleomorphic liposarcomas possessed the most frequent genomic imbalances (mean number 16.3) of all liposarcoma subtypes investigated. These imbalances were in almost all chromosomal regions detected predominantly as over-representations of chromosomes 1, 5p, 13q, and 22q. Summarizing, all subtypes but well-differentiated liposarcomas showed gains of 13q, which were associated with a poor prognosis.  相似文献   
5.
 Energy-rich phosphates, [ATP]/[ADPfree] ratios, and the myosin heavy chain (MHC) complement were determined in single fibres from normal rabbit muscles, and in fibres isolated from tibialis anterior muscle undergoing fast-to-slow conversion by chronic low-frequency stimulation (CLFS). In normal muscles, energy-rich phosphate contents and [ATP]/[ADPfree] ratios could thus be assigned to different MHC-based fibre types. Phosphocreatine (PCr) contents and [ATP]/[ADPfree] ratios differed markedly between fast- and slow-twitch fibres, as well as within the fast fibre subtypes. Both magnitudes were approximately twofold higher in the fastest (type IIB) fibres as compared to the slowest (type I) fibres. According to PCr contents and [ATP]/[ADPfree] ratios pure and hybrid fibres were aligned in an order similar to that determined by their contractile properties and myofibrillar ATPase activities. CLFS for up to 30 days induced pronounced decreases in PCr and [ATP]/[ADPfree] which attained levels twofold lower than in normal slow-twitch fibres. In both normal and stimulated muscles, PCr and [ATP]/[ADPfree] ratios were correlated, indicating their equilibrium in the different fibre types. The relationship detected between MHC isoform expression and the [ATP]/[ADPfree] ratio suggests that the drastic and persistent depression of the cellular energy state may act as an important signal initiating fast-to-slow transformation processes in muscle fibres. Received: 26 June 1998 / Accepted: 31 July 1998  相似文献   
6.
OBJECTIVES: To review the traumatic injuries that have been associated with acupuncture and to discuss how these adverse effects may be reduced by increased awareness of normal anatomy and anatomical variations. METHODS: Literature search accompanied by postmortem anatomical studies. RESULTS: Traumatic lesions after acupuncture have been described in thoracic and abdominal viscera, in the peripheral and central nervous systems, and in blood vessels. Deaths have been recorded from pneumothorax and cardiac tamponade. The anatomical structure of the body at several acupuncture points is such that needles can reach vulnerable structures. CONCLUSION: While the frequency of adverse effects of acupuncture is unknown and they may be rare, knowledge of normal anatomy and anatomical variations is essential for safe practice and should be reviewed by regulatory bodies and those responsible for training courses.  相似文献   
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Tönnies H  Huber S  Kuhl JS  Gerlach A  Ebell W  Neitzel H 《Blood》2003,101(10):3872-3874
Fanconi anemia (FA) is a condition that induces susceptibility to bone marrow failure, myelodysplastic syndrome (MDS), and leukemia. We report on a high incidence of expanding clonal aberrations with partial trisomies and tetrasomies of chromosome 3q in bone marrow cells of 18 of 53 FA patients analyzed, detected by conventional and molecular cytogenetics. To determine the clinical relevance of these findings, we compared the cytogenetic data, the morphologic features of the bone marrow, and the clinical course of these patients with those of 35 FA patients without clonal aberrations of 3q. The 2 groups did not differ significantly with respect to age, sex, or complementation group. There was a significant survival advantage of patients without abnormalities of chromosome 3q. Even more pronounced was the risk assessment of patients with gains of 3q material with respect to the development of morphologic MDS and acute myeloid leukemia (AML). Thus, our data from 18 patients with 3q aberrations reveal that gains of 3q are strongly associated with a poor prognosis and represent an adverse risk factor in FA.  相似文献   
9.
Millions of individuals with posttraumatic stress disorder (PTSD) are parents. A burgeoning literature suggests that offspring of parents with this condition may be at increased risk for psychological problems. The current paper provides an integrative and comprehensive review of the diverse research literature examining the sequelae of parental posttraumatic stress among offspring. Over 100 studies that evaluated psychological and/or biological variables among children of parents with PTSD are reviewed. Findings suggest parental symptoms of posttraumatic stress are uniquely related to an array of offspring outcomes, including internalizing-type problems, general behavioral problems, and altered hypothalamic-pituitary-adrenal axis functioning. Although very little work has directly evaluated mechanisms of transmission, there is increasing support for genetic and epigenetic effects as well as parenting behaviors. These and other mechanisms are discussed; drawing upon findings from other literatures to consider how parental PTSD may impart psychobiological vulnerability upon offspring. We conclude with a detailed discussion of the methodological strengths and challenges of the extant research, along with a recommended agenda for future research in this important area of study.  相似文献   
10.
Scientific understanding of mother–infant HPA axis attunement has been limited by discrepant methods for assessing attunement that often conflate different levels of association. We sought to refine the conceptualization of attunement by investigating whether mother–infant cortisol attunement exists as coupling of response trajectories within an acute stress episode, separate from shared developmental patterns and/or overall dyadic similarity in cortisol levels, and whether the degree of attunement depends on within‐ or between‐dyad differences in maternal risk and protective factors. We examined these questions using a longitudinal study with mother/infant salivary cortisol during dyadic stressors at 6, 12, and 18 months postnatal. A three‐level hierarchical linear model showed that sample‐wide associations between mother and infant cortisol were not significant at any level, suggesting normative lack of attunement; however, there was significant variability in degree of attunement across dyads. Concurrent levels of family resources and social support satisfaction predicted lower mother–infant cortisol attunement within the session, and overall (mean) parenting stress predicted the opposite. Follow‐up analyses showed this was typically due to an increase in infants’ (but not their mothers’) within‐session cortisol response slopes with increasing support and decreasing stress. Implications for the role of mother–infant cortisol attunement in intergenerational stress transmission are discussed.  相似文献   
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