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991.
992.
Few studies addressing possible immune sequelae of long-term whole blood donation have been published. The purpose of this study was to determine if there were any differences in lymphocyte subsets, monocyte and neutrophil receptors, and antigens important to host defense in committed whole blood donors and in nondonor controls. Blood samples were obtained from 27 whole blood donors who had been donating on a regular basis for at least 4 years and from 21 nondonor controls. A panel of single- and dual-labeled monoclonal antibodies was used to characterize peripheral white cells, and then the cells were analyzed by flow cytometry. Lymphocyte subsets included T (CD3) cells, helper T (CD4) cells, suppressor T (CD8) cells, B (CD19) cells, natural killer (NK) (CD56) cells, and subpopulations of T cells defined by the coexpression of markers for CD3/HLA-DR, CD3/CD56, and CD8/CD11b. Monocyte and neutrophil analysis included quantitation of receptors for C5a, formyl-met-leu-phe, and C3bi (CR3). Monocytes were also analyzed for expression of HLA-DR and CD14 antigens. No significant differences were observed in the whole blood donors and nondonor controls for any of these factors used to assess immunologic status, except for an increase in C3bi receptors on both neutrophils and monocytes from whole blood donors. These findings indicate that the lymphocyte parameters analyzed in this study are unaltered by long-term whole blood donation. Further research is necessary to determine the significance of complement receptor upregulation in whole blood donors and to identify any changes in the functional characteristics of peripheral white cells from whole blood donors. 相似文献
993.
G. A. W Bruyn R. van Furth 《European journal of clinical microbiology & infectious diseases》1991,10(11):897-910
Streptococcus pneumoniae is the primary cause of community-acquired pneumonia, meningitis in adults and otitis media in infants and children and the third cause of meningitis in infants and children. Despite the availability of effective therapeutic agents against this pathogen, mortality has remained high, particularly for infections complicated by bacteremia. For many years, there has been a plea for vaccination. The first steps, using whole bacterial vaccines, were taken during the early decades of this century in the gold mining camps of South Africa, where pneumonia was endemic. The efficacy of purified pneumococcal polysaccharide vaccines has since been demonstrated in young adults, such as gold miners and military recruits, as well as for several other groups at risk, such as institutionalized elderly, patients with sickle cell anemia or those who have undergone a splenectomy, and elderly patients with underlying conditions such as chronic obstructive pulmonary disease and chronic cardiovascular disease, but not in infants and severely immunocompromised patients. Serological studies on the immune response to inoculation of pneumococcal polysaccharide antigens have demonstrated a severely impaired antibody response in the last two groups. Therefore, development of more highly immunogenic vaccines, e.g. by linking pneumococcal polysaccharides or parts of them to protein carriers, should be continued in an attempt to offer adequate protection to those who are insufficiently protected by the current 23-valent polysaccharide vaccine. Opportunities to immunize other patients who are at risk for pneumococcal infection and are capable of responding to the current vaccine should not be missed. 相似文献
994.
Antibiotic prophylaxis in craniotomy: a prospective double-blind placebo-controlled study 总被引:1,自引:0,他引:1
B van Ek B A Dijkmans H van Dulken R van Furth 《Scandinavian journal of infectious diseases》1988,20(6):633-639
A prospective double-blind placebo-controlled study was performed to evaluate the efficacy of cloxacillin for the prevention of infections after craniotomy. 310 patients were admitted to the study. 39 died within 90 days after craniotomy without an infection, 20 and 19 of them belonging to the cloxacillin and placebo groups, respectively. In the cloxacillin group 6 neurosurgical infections occurred after 183 operations (3.3%) in 156 patients (3.9%), and in the placebo group 20 after 195 operations (10.3%) in 154 patients (13%). These differences between the 2 groups are statistically significant (p less than 0.01 and p less than 0.05 for patients and operations, respectively). For a craniotomy subgroup, there was no significant difference in infection rate between the cloxacillin and placebo groups. We conclude that cloxacillin significantly reduces the rate of infection after craniotomy, and recommend administration of this antibiotic for prophylaxis in patients undergoing this operation. 相似文献
995.
996.
J J Hoogeterp H Mattie A M Krul R van Furth 《Scandinavian journal of infectious diseases》1988,20(6):649-656
The effect of rifampicin on Staphylococcus aureus in vitro was assessed as the difference between the logarithms of the numbers of colony forming units (CFU) with and without 3 h of exposure to the drug. The efficacy was expressed as the EC50, i.e. the concentration at which 50% of the maximal effect was obtained, calculated according to the Hill equation. The value found for the EC50 was 3.8 micrograms/l and the mean maximal effect was a log ratio of 5.03 (SEM 0.33). In vivo experiments were performed in normal mice and in mice made granulocytopenic by irradiation. The effect of rifampicin was assessed as the CFU count 5 h after the injection of a suspension of bacteria into the thigh muscle and 4 h after the administration of rifampicin. The efficacy was expressed as the ED50, i.e. the dose at which 50% of the maximal effect is obtained. This value was 0.18 mg/kg for the normal mice and 0.15 mg/kg for the granulocytopenic mice. The corresponding mean plasma concentrations of non-protein-bound drug were 28 and 24 mg/l, respectively. Thus, the EC50 was found to be much higher in vivo than that in vitro. This difference should be taken into account when parameters of in-vitro efficacy are applied to establish dosage schedules. 相似文献
997.
998.
999.
1000.
Impaired antibody response after immunization of HIV-infected individuals with the polysaccharide vaccine against Salmonella typhi (Typhim-Vi). 总被引:3,自引:0,他引:3
Infections with Salmonella species, including Salmonella typhi, are more frequently observed in HIV-infected individuals than in healthy individuals. HIV-infected individuals were vaccinated with polysaccharide vaccine against Salmonella typhi (Typhim-Vi) which is assumed to be a T-cell-independent antigen. We found that the antibody response in patients with < 200 x 10(6)/l CD4+ T lymphocytes was significantly lower compared with patients with > or = 200 x 10(6)/l CD4+ T lymphocytes and healthy controls. The antibody response after vaccination with the polysaccharide salmonella Vi-antigen was correlated with the number of CD4+ T lymphocytes and therefore Typhim-Vi can be considered to be a T-cell-independent type 2 antigen. The results of this study indicate that after vaccination the proportion of HIV-infected individuals with protective antibody concentrations against Salmonella typhi will be lower than in healthy controls. 相似文献