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Chromosome abnormalities influence prognosis and tumour progression in B-cell Chronic Lymphocytic Leukaemia (CLL). This study sought to determine whether these different disease subgroups were associated with unique gene expression patterns. Thirty-four cases of CLL were screened for the 11q23, 13q14, 17p13 deletions, and trisomy 12 by fluorescence in situ hybridization (FISH). Expression of 205 cell signalling and apoptosis genes were compared by cDNA array among cases with different chromosome abnormalities. A majority of the statistically differentially expressed genes were present in the 11q23 deletion group by hierarchical clustering. CDC2, a serine/threonine kinase, was overexpressed in the 11q23 deletion group (P = 0.0004) and confirmed by Taqman real-time polymerase chain reaction. Several other genes associated with cell signalling were overexpressed in the 11q23 deletion group. A strong overall correlation existed between the presence of different chromosome abnormalities and a number of prognostic factors including immunoglobulin heavy chain variable region mutation status (P = 0.011), time to treatment (P = 0.025) and lymphocyte doubling time (P = 0.034). This study confirmed the prognostic impact of chromosome abnormalities identified by FISH in CLL, particularly the 11q23 deletion and trisomy 12. In addition, the 11q23 deletion group was associated with a unique gene expression pattern involving cell signalling and apoptosis genes.  相似文献   
993.
Kin caregiving research tends to focus on the experiences of grandmothers. Often unnoticed and underserved are grandfathers who also take on this responsibility. Here, two groups of grandfathers participated in focus group interviews to discuss their experiences as caregivers to their grandchildren. Common themes for the grandfathers were the feeling of missing freedom, experiencing child rearing differently now than they had with their own children, and fear of what would happen to the children should their health fail. Thirty-three grandfathers also answered questions about themselves; their grandchild; need, use, and satisfaction with formal services; depression; and caregiving mastery. A sample of 33 grandmothers selected from a previous study was matched to the grandfathers on age, race, and marital status. Differences in depressive symptoms between the grandfathers and grandmothers were statistically significant. There was no statistically significant difference between the grandparent caregivers on caregiving mastery. These findings suggest that there may be differences in the impact of caregiving for grandmothers and grandfathers. These differences should be further investigated.  相似文献   
994.
Highly active antiretroviral therapy has decreased the morbidity and mortality of human immunodeficiency virus (HIV) infection, but latently infected cells remain for prolonged periods. CD4(+) CD45RO(+) T cells are a major latent virus reservoir in HIV-infected persons. Replication-competent, latently HIV-infected T cells can be generated in vitro by infecting peripheral blood mononuclear cells with HIV and then eliminating the HIV-producing cells with an anti-CD25 immunotoxin (IT). The CD25(-) latently infected cells then can be eliminated with an anti-CD45RO IT. This study determined whether this IT also could kill latently infected CD4 T cells from HIV-infected persons with or without detectable plasma viremia. The results show that ex vivo treatment of cells from HIV-positive persons by anti-CD45RO IT reduces the frequency of both productively and latently infected cells. In contrast, CD4(+) CD45RA(+) naive T cells and a proportion of CD4(+) CD45RO(lo) memory T cells are spared.  相似文献   
995.
OBJECTIVE: The prevalence and main determinants of exocrine pancreatic insufficiency were investigated in a large population-based sample of older adults by measuring pancreatic elastase-1 in stool. MATERIAL AND METHODS: The study comprised 914 participants aged 50 to 75 years recruited by their general practitioner during a general health examination. All participants and their physicians were asked to fill out a standardized questionnaire which contained information on socio-demographic and lifestyle factors as well as medical history. Native stool was examined for pancreatic elastase-1 with a commercially available ELISA (ScheBo Tech, Giessen, Germany). RESULTS: Overall, 524 women and 390 men aged 50 to 75 years (mean age 61.9 years) were included in the analysis. In total, 105 (11.5%) of the 914 subjects showed signs of exocrine pancreatic insufficiency (EPI) with =200 microg elastase-1/g stool, and 47 (5.1%) subjects showed signs of a severe exocrine pancreatic insufficiency (SEPI, < 100 microg elastase-1/g stool). There was a clear increase in EPI with age. Patients taking angiotensin-converting enzyme (ACE) inhibitors had a lower prevalence than subjects without this medication; these associations persisted after adjustment for covariates. CONCLUSIONS: Prevalence of EPI increases with age and seems to be tentatively higher in men than in women. However, smoking seems to be an independent risk factor for EPI and SEPI whereas ACE-inhibitor intake might be a protective factor. The latter finding may even point to new options in the treatment of chronic pancreatitis.  相似文献   
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The human immunodeficiency virus (HIV) type 1 displays a high degree of genetic variation, especially in the glycoprotein (gp120) domain of the envelope gene. To determine whether this genomic heterogeneity leads to the expression of independent HIV subtypes, 12 sera from HIV type 1 antibody-positive individuals were tested for their ability to neutralize 20 HIV isolates of various origins. Four distinct HIV subtypes with different sensitivity to serum neutralization were identified. These results suggest that a finite number of HIV subtypes exist and that the combined use of selected HIV isolates representing several subtypes may be necessary for the development of an effective vaccine.  相似文献   
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