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91.
92.
The research literature on AIDS prevention efforts contains many reports on the impact of intervention sessions. Little information is available, however, on the success of various strategies to recruit clients to attend these sessions. An assessment of the comparative impact of money and other types of incentives on group attendance in two AIDS risk reduction projects, in the Harlem area of New York City and in Cleveland, OH, was undertaken. In both projects, injecting drug users and the sex partners of injecting drug users were recruited to participate in group sessions that focused on the reduction of AIDS risk behaviors. Data on group attendance were analyzed for 838 people in the New York project and 1,168 in the Ohio project. After the projects were underway, attendance incentives at both were changed from money to food coupons or gift certificates. Results indicated that a nonmonetary incentive was associated with a significant decline in group attendance. Concerns regarding paying monetary incentives to injecting drug users are discussed.  相似文献   
93.
BACKGROUND: A recently discovered DNA virus (SEN) has been assumed to be responsible for posttransfusion hepatitis in humans. Phylogenetic analysis of SEN virus has revealed the existence of 8 different strains. Two of them (SEN virus strain H (SENV-H) and SENV-D) have been described as possible candidate viruses for inducing posttransfusion hepatitis. Until now, it is unclear whether patients on maintenance hemodialysis are on increased risk for acquiring SEN virus. OBJECTIVES: To investigate the prevalence of SENV-H among patients on maintenance hemodialysis and to examine whether special measures have to be taken to prevent nosocomial spreading of the virus. STUDY DESIGN: Serum samples derived from 78 chronically hemodialysed patients were examined for SENV-H viremia by seminested polymerase chain reaction. A panel of 226 samples from healthy blood donors served as a control group. RESULTS: The prevalence of SENV-H was determined to be 12.8% (n=10) among patients on maintenance hemodialysis. This is nearly the same prevalence as in healthy blood donors (16.8%; n=38). None of the solely SENV-H-viremic individuals had clinical or biochemical signs of liver disease. Enhanced severity of liver disease could not be observed in patients coinfected with hepatitis C virus and SENV-H. CONCLUSION: We conclude that SENV-H viremia is widespread among hemodialysis patients. Since no viremic patient had clinical or biochemical signs of liver disease, in our setting the hepatitis-inducing capacity of SENV-H remains unclear. On the basis of our results, at present, we do not regard it as necessary to dialyse SENV-H-viremic patients on separate machines.  相似文献   
94.
Background For the diagnosis of NF 2, ocular findings like juvenile cataract, retinal and combined hamartomas of the retinal pigment epithelium and the retina as well as tumours of the optic nerve play an important role. An early diagnosis is essential in order to inhibit deafness from bilateral vestibular schwannoma. But sometimes the Manchester diagnostic criteria for NF2 are not completely fulfilled. Frequently, suspicious macular anatomy is found in neurofibromatosis 2 (NF2) patients. We hypothesise that the underlying retinal pigment epithelium or the retina of the macular region alters in NF2 patients. Therefore, we have tested by fluorescence angiography whether NF2 is associated with chorioretinal changes. Methods and patients In a prospective study, 48 patients matching the criteria for NF2 with known genotype underwent a complete ophthalmic examination including funduscopy and fluorescence angiography. The influence of the genotype was statistically analysed by odds ratios and their 95% confidence intervals. Results Eleven eyes of nine patients showed choroidal hyperfluorescence in the macular region on fluorescence angiography. There was staining spreading from grainy hyperfluorescence to minor variants of a combined hamartoma of the retina and the retinal pigment epithelium. All of these manifestations presented without leakage in the late angiographic phases. These choroidal findings were present in one patient with frameshift mutation, in two patients with nonsense mutations and in six patients with splice site mutations of the NF2 gene. The statistical analysis showed a significant lower risk of choroidal alterations in patients with somatic mosaicism, deletions and unfound mutations. Conclusion Using fluorescence angiography pathological changes of the macular region can be detected in NF2 patients. The ophthalmic examination, which often is limited to the anterior eye segment, may play a role in finding the diagnosis in incomplete NIH criteria. The presented study shows chorioretinal hyperfluorecences without leakage of the macular region, which might be considered as a forme fruste of a hamartoma. Choroidal hyperfluorescences add to the spectrum of genotype-phenotype correlations in NF2. Grant information: Supported in part by Deutsche Krebshilfe 70–2450-Ma2 to VFM and LK. Sequencing was done on an ABI310 sequencer donated by the Rodulf Bartling Stiftung.  相似文献   
95.
Monoclonal antibodies were induced against leukemic T cells from a patient with chronic lymphocytic leukemia exhibiting natural killer (NK) activity. Two antibodies, termed T811 and M522, reacted by indirect immunofluorescence with distinct subpopulations of normal human mononuclear blood cells. The antibody T811 defines a surface antigen which is restricted to a subset of the T cell lineage. The antigen recognized by the second antibody, M522, is expressed on monocytes and polymor-phonuclear leukocytes and, in addition, on 9–17% of nonadherent peripheral blood leukocytes (NAL). It is shown that the total NK activity of NAL is confined to the subset of cells expressing the M522-defined antigen. Moreover, the portion of NK cytotoxicity associated with T lymphocytes is mediated by a subpopulation which is characterized by the simultaneous expression of the T811- and the M522-defined antigens. This population comprises about 4% of NAL and could be isolated to a purity of > 85%.  相似文献   
96.
Recent studies reported DEPDC5 loss‐of‐function mutations in different focal epilepsy syndromes. Here we identified 1 predicted truncation and 2 missense mutations in 3 children with rolandic epilepsy (3 of 207). In addition, we identified 3 families with unclassified focal childhood epilepsies carrying predicted truncating DEPDC5 mutations (3 of 82). The detected variants were all novel, inherited, and present in all tested affected (n = 11) and in 7 unaffected family members, indicating low penetrance. Our findings extend the phenotypic spectrum associated with mutations in DEPDC5 and suggest that rolandic epilepsy, albeit rarely, and other nonlesional childhood epilepsies are among the associated syndromes. Ann Neurol 2014;75:788–792  相似文献   
97.
Rolandic epilepsy (RE) and its atypical variants (atypical rolandic epilepsy, ARE) along the spectrum of epilepsy–aphasia disorders are characterized by a strong but largely unknown genetic basis. Two genes with a putative (ELP4) or a proven (SRPX2) function in neuronal migration were postulated to confer susceptibility to parts of the disease spectrum: the ELP4 gene to centrotemporal spikes and SRPX2 to ARE. To reexamine these findings, we investigated a cohort of 280 patients of European ancestry with RE/ARE for the etiological contribution of these genes and their close interaction partners. We performed next‐generation sequencing and single‐nucleotide polymorphism (SNP)–array based genotyping to screen for sequence and structural variants. In comparison to European controls we could not detect an enrichment of rare deleterious variants of ELP4, SRPX2, or their interaction partners in affected individuals. The previously described functional p.N327S variant in the X chromosomal SRPX2 gene was detected in two affected individuals (0.81%) and also in controls (0.26%), with some preponderance of male patients. We did not detect an association of SNPs in the ELP4 gene with centrotemporal spikes as previously reported. In conclusion our data do not support a major role of ELP4 and SRPX2 in the etiology of RE/ARE. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here .  相似文献   
98.
99.
The activation of complement components in human serum has been studied using immunoglobulins adsorbed to microtiter plates. The sequential deposition of complement fragments was detected by a series of mono- and polyclonal antibodies in an indirect enzyme-linked immunosorbent assay (ELISA). Antibodies against C1q, C1s, C4b/d, C3b/d, factor B, C5b-9 membrane attack complex (MAC), the regulatory complement proteins C4 binding protein (C4bp) and properdin were reactive. Several lines of evidence suggest that complement activation was via the classical pathway: (1) complement activation was highly isotype-restricted with regard to the adsorbed Igs (human IgG1 and IgG3 as well as mouse IgM, IgG2a and IgG2b isotypes are strong activators in contrast to human IgG2, IgG4, IgA and mouse IgG1); (2) Ca2+ depletion, heat treatment (56 degrees C for 45 min), incubation with 0.5 M KSCN or heat-aggregated immunoglobulins (aggIgG) abrogated serum activity; (3) complement deficient sera (C1q def', C2 def', C6 def' human sera; C2 def', C4 def' guinea pig sera) showed impaired deposition of the complement components that follow the missing component in the cascade of activation. In a clinical study sera from patients with systemic lupus erythematosus (SLE) were investigated in order to measure the effect of hypocomplementemia due to complement consumption. The results obtained suggest that this new and simple assay is well suited for (1) the detection of various inherited complement deficiencies, (2) the semiquantitative evaluation of sera with decreased complement levels, (3) a more detailed study of complement components bound to a solid phase.  相似文献   
100.
Complement activation in human lymphoid germinal centres   总被引:2,自引:0,他引:2       下载免费PDF全文
The presence of complement activation products has been studied in morphologically normal human lymphatic tissue from tonsil, spleen and lymph node. Newly established monoclonal antibodies (mAbs) with reactivity against the C4 cleavage fragments C4a, C4b, C4c and C4d were applied on cyrostat sections in the indirect immunoperoxidase staining technique. Irrespective of organ type, C4d activation product could be detected in germinal centres of all secondary lymphoid follicles. To substantiate this finding, the complete sequence of complement activation products was investigated by a series of mono- and polyclonal antibodies to the complement proteins C1, C2, C3, factor B, C5, C9 to C5b-9 neoantigens and to the regulatory complement proteins C4 binding protein (C4bp), factor I, factor H and properdin. Similar to C4d, all secondary follicles exhibited a strong staining reaction for C3d antigens restricted to germinal centres. At the same site, albeit with distinctly weaker intensity, components of the membrane attack complex (MAC) C5b-9 were found. The simultaneous deposition of C1, C4b and C4bp in certain germinal centres indicates that complement activation is induced via the classical pathway. Concomitant deposition of IgM suggests IgM-antigen complexes that have been trapped on follicular dendritic cells (FDC) during normal immune response as the most likely candidates for activators of the classical pathway. Our data demonstrate that human lymphoid germinal centres as important sites of immune regulation closely interrelate with the complete cascade of complement-activation products, including the membrane attack complex (MAC).  相似文献   
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