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691.
In bacterial meningitis, excessive immune responses carry significant potential for damage to brain tissue even after successful antibiotic therapy. Bacterial meningitis is regarded primarily as the domain of innate immunity, and the role of lymphocytes remains unclear. We studied the contribution of lymphocytes to acute inflammation and neurodegeneration in experimental Toll-like receptor 2-driven meningitis, comparing wild-type mice with RAG-1-deficient mice that have no mature T and B lymphocytes. At 24 h after intrathecal challenge with the synthetic bacterial lipopeptide Pam3CysSK4, RAG-1-deficient mice displayed more pronounced clinical impairment and an increased concentration of neutrophils, reduced expression of interleukin-10 (IL-10) mRNA, and increased expression of CXCL1 mRNA in the cerebrospinal fluid. Conversely, neuronal loss in the dentate gyrus was reduced in RAG-1-deficient mice, and expression of IL-10, transforming growth factor β and CCL2 mRNA by microglia was increased compared to wild-type mice. Adoptive transfer of wild-type lymphocytes reversed the enhanced meningeal inflammation and functional impairment observed in RAG-1-deficient mice. Our findings suggest compartment-specific effects of lymphocytes during acute bacterial meningitis, including attenuation of meningeal inflammation and shifting of microglial activation toward a more neurotoxic phenotype.  相似文献   
692.
Monoclonal and oligoclonal gammopathy after bone marrow transplantation   总被引:1,自引:1,他引:1  
Serial serum protein electrophoreses were performed on 60 patients undergoing allogeneic and syngeneic bone marrow transplantation (BMT). More than 50% of patients (31 of 60) developed transient oligoclonal and monoclonal gammopathies that appeared an average of 84 days posttransplantation (range 27 to 336 days) and persisted an average of 175 days (range 14 to 652 days). Immunofixation analysis revealed 82% of the M components to be of the immunoglobulin G (IgG) type and 18% to be IgM; 56% were kappa and 44% were lambda. A strong correlation between development of graft versus host disease (GVHD) and appearance of M components was observed (73% incidence in GVHD patients v 27% in non-GVHD patients, P = .0003). Two of the three syngeneic graft recipients also developed monoclonal gammopathies. Evidence of oligoclonal circulating B-cell populations was found in 68% of patients posttransplantation by flow cytometric B-cell clonal excess assay. No correlation of recovery of particular B- or T-lymphocyte subsets and development of M components was seen. The development of transient oligoclonal and monoclonal gammopathies after transplantation may be a ubiquitous finding reflecting recapitulation of early B-cell ontogeny.  相似文献   
693.
T cell depletion of donor bone marrow can prevent graft v host disease (GVHD) in human and murine marrow graft recipients. However, engraftment in the recipient may be compromised as a consequence of donor marrow T cell depletion. The effect of recombinant murine granulocyte/macrophage colony-stimulating factor (rmu GM-CSF) on engraftment and hematologic reconstitution was evaluated in a murine allogeneic bone marrow transplantation (BMT) model involving T cell depletion of marrow. Before transplantation into irradiated mice differing at major and minor histocompatibility loci, rmu GM-CSF was preincubated with T cell-depleted donor marrow. When low degrees of engraftment were noted in control recipients, treatment of donor marrow with high concentrations of rmu GM-CSF led to enhanced engraftment. Ex vivo donor graft incubation with rmu GM-CSF or a single in vivo injection of rmu GM-CSF were both effective means of promoting engraftment. When the engraftment rate in control recipients was high, rmu GM-CSF did not have an identifiable effect. Only slight increases in hematologic recovery were detected regardless of the rate of engraftment. Neither post-BMT survival nor marrow stem cell capacity was affected by rmu GM-CSF incubation. Furthermore, growth factor administration did not have a significant effect on the incidence of GVHD in recipients of non-T cell-depleted bone marrow splenocyte preparations. In vitro natural killer-mediated target cell lysis was not altered by incubation of effector cells with rmu GM-CSF. These results demonstrate the potential of ex vivo rmu GM-CSF treatment of donor marrow to facilitate engraftment across extensive histo- compatibility barriers.  相似文献   
694.
Blazar  BR; Taylor  PA; Vallera  DA 《Blood》1995,86(11):4353-4366
To determine if in utero transplantation could restore the immune system of mice with a severe combined immunodeficiency (SCID) disorder, C57BL/6Sz-scid/scid fetuses were injected on day 14/15 of gestation with adult congenic donor bone marrow (BM) cells. Congenic BM engrafted in one of eight (13%) recipients. Reconstitution of both lymphoid and nonlymphoid lineages was observed. In vitro and in vivo T-cell function was documented. Stem cells were shown to have engrafted by secondary transfer studies. When fully allogeneic C57BL/6 (H-2b) or B10.BR (H-2k) adult. BM cells were given to C.B-17-scid/scid (H-2d) fetal recipients, 15 of 54 (28%) recipients had evidence of engraftment, with up to 76% of peripheral blood (PB) being of in utero donor BM origin on day 131 postnatally. In all mice with persistent leukocyte engraftment, T- and B-lymphoid cells were entirely of donor origin. Donor T cells were tolerant to host but not third party alloantigens as measured in vitro. In vivo, T-cell function appeared intact. Although most mice had lower levels of B-cell engraftment than T-cell engraftment, mice with > or = 10% B cells were able to produce normal levels of IgM. Despite transplantation of fully allogeneic BM cells, stem cell engraftment could be demonstrated by secondary transfer of BM cells into lethally irradiated recipients that were congenic to the original in utero donor BM source. These data indicate that adult BM cells, even those fully allogeneic with the fetal recipient, can give rise to progeny with multilineage potential, which leads to restoration of T-cell and B-cell function.  相似文献   
695.
Breitman  TR; Collins  SJ; Keene  BR 《Blood》1981,57(6):1000-1004
The recent finding that retinoic acid induces terminal granulocytic differentiation of the human promyelocytic leukemia cell line, HL-60, prompted an investigation of the sensitivity to this inducer of human myelocytic leukemia cells in primary suspension culture. Of the 21 leukemic specimens, only cells from the two patients with acute promyelocytic leukemia differentiated in response to retinoic acid. After an incubation period of 5--7 days in 1 microM retinoic acid, the cells from these two patients showed extensive morphological and functional maturation. Thus, because it appears that retinoic acid specifically induces granulocytic differentiation of leukemic promyelocytes, this compound may have therapeutic utility in the treatment of acute promyelocytic leukemia.  相似文献   
696.
Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? In this study we observed courses of micturition symptoms and differentiated degrees of symptoms for each point in time while also considering the impact of bothersomeness. Our data show that not only significantly more patients who have undergone BT suffer from OAB than those who have undergone RP, but also that those affected show significantly higher values for severity of OAB symptoms throughout the whole observation period of 36 months. Our data analysis further shows that variability of OAB symptoms as well as fluctuation of severity of OAB symptoms vary to a significantly higher degree after BT than after RP. Looking only at mean figures at a given point in time clearly underestimates the underlying problem. This fact is not reflected in the literature.

OBJECTIVE

  • ? To look at individual courses of postoperative micturition symptoms, especially urgency, in patients treated either with radical prostatectomy (RP) or with brachytherapy (BT).

PATIENTS AND METHODS

  • ? In a prospective longitudinal study we investigated individual changes in micturition symptoms before treatment, and 6, 12, 24 and 36 months after treatment.
  • ? All patients received the European Organization for the Research and Treatment of Cancer quality‐of‐life questionnaire, QLQ‐C30, and the International Continence Society male questionnaire at each assessment.
  • ? We looked at long‐term results as well as changes in time using repeated measures analysis of variance. We further analysed fluctuation of symptoms using sum of changes.

RESULTS

  • ? Of the 389 patients treated consecutively in our clinic over the last few years, 99 patients with a mean (sd ) age of 65 (6.3) years had completed all five questionnaires and thus were further analysed. Of these, 66 (66.7%) were treated with RP and 33 (33.3%) with BT.
  • ? With the exception of age, no significant difference was found between the treatment groups either in physical functioning or in prevalence and severity of overactive bladder (OAB) symptoms.
  • ? Adjusted for age and pretreatment symptoms in analysis of covariance, we found that there were statistically more symptoms of OAB 36 months after BT compared with those patients treated with RP (P < 0.025). Whereas 30% of patients complained about severe symptoms of urgency after BT, only 11% did so after RP.
  • ? Changes of severity of OAB symptoms over the course of time (P < 0.007) using analysis of repeated measures as well as variability of OAB symptoms (P < 0.033) using the two‐sided Wilcoxon t‐test were significantly higher in patients treated with BT than in patients treated with RP.

CONCLUSIONS

  • ? Independently of age and physical functioning, BT is significantly associated with higher rates of long‐term urgency symptoms, even after 3 years.
  • ? Repeated measurements show that OAB symptoms are highly fluctuating and that in patients treated with BT, severity of symptoms as well as variability of symptoms was significantly higher than in those patients treated with RP.
  • ? Persistent OAB seems to be an underestimated problem after treatment for localized prostate cancer, especially in patients treated with BT.
  相似文献   
697.
698.
To determine the efficacy of various methods of confidential unit exclusion (CUE) among donors at increased risk of HIV exposure, we surveyed AABB institutional members on their experience with 3 CUE methods: ballot or barcode, completed at the time of donation, and call-back, performed by the donor after leaving the donor center. From June 1985 to December 1987, 5,049,883 donations at 48 donor centers were evaluable for analysis. The results of this survey suggest that ballot and barcode methods of CUE are important adjuncts to other donor screening procedures in identifying potentially infectious units, and that both of these methods are superior to the call-back system of unit exclusion.  相似文献   
699.
新生儿免疫性血小板减少症(Neonatalalloimmunethrom-bocytopenia,NATP)发病原因是由于母体产生针对胎儿特异性血小板抗原的IgG抗体,并发生抗原抗体反应。胎儿特异性血小板抗原来自父亲。NATP发病率约为0.l%。NATP占新生儿血小板减少症的3%和重度血小板减少(血小板计数<50×109  相似文献   
700.
BACKGROUND: Several cold autoantibodies (usually IgG) with IT specificity have been reported previously, as have autoantibodies with joint I and P blood group specificities (IP1, ITP1, iP1, IP). A fatal outcome associated with an IgM cold autoantibody of ITP specificity is reported. CASE REPORT: A 54-year-old man suffered from progressively severe cold autoimmune hemolytic anemia for 9 months. Hemoglobin concentration ranged from 6 to 7 g per dL (60-70 g/L) and reticulocytes from 3 to 5 percent (0.030-0.050). The direct antiglobulin test was weakly positive for IgM and strongly positive for C3d. The serum contained a cold agglutinin that reacted strongest with cord i red cells (RBCs) > adult I RBCs > adult i RBCs, which is consistent with IT specificity. The Donath-Landsteiner test was positive; the reaction was neutralized by globoside. The serum reacted weakly or was negative with RBCs from five group p blood donors, which suggests anti-ITP specificity. Dithiothreitol treatment of the serum abolished the cold agglutinin reactivity, which suggests that the anti-IT was IgM. The patient received > 40 RBC transfusions and failed to respond to oral steroids, oral cytoxan, high-dose pulse intravenous steroids, and plasma exchange at room temperature and at 35 degrees C. He died of sepsis following an unsuccessful trial of chlorambucil. Autopsy revealed unsuspected disseminated non-Hodgkin's lymphoma. CONCLUSION: Serologic studies are consistent with our patient's having a single IgM cold autoantibody with IT and P specificities (anti-ITP) and requiring both specificities on the same RBC to permit maximal antibody expression.  相似文献   
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