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21.
22.
Erlandson KM Allshouse AA Duong S Mawhinney S Kohrt WM Campbell TB 《Journal of palliative medicine》2012,15(10):1124-1129
Abstract Introduction: Studies of advance care planning (ACP) completion rates in HIV-infected persons pre-date the "graying" of the HIV epidemic. We sought to examine current ACP completion rates and factors influencing completion among HIV-infected persons. Methods: HIV-1-seropositive persons aged 45-65 years on effective antiretroviral therapy for a minimum of 6 months were enrolled in a cross-sectional survey. Likelihood of ACP was assessed by demographic and clinical characteristics, tested with odds ratios (OR) and 95% Wald confidence intervals (CI), and adjusted for gender. Results: Of 238 participants, 112 (47%) completed ACP. Persons ≥55 years of age (OR 2.8; CI 1.6,5.0; p<0.001), males (OR 4.1; CI 1.8,9.3; p=0.004), and persons with higher education (OR 2.2; CI 1.3,4.0; p=0.007) were more likely to have completed ACP. Persons with a cardiac event were more likely to have completed ACP (OR 5.5; CI 1.6,25; p=0.03), although this effect was diminished after adjusting for gender (OR 4.5; CI 0.95,21.4; p=0.06). HIV infection diagnosed for greater than 5 years was not associated with ACP completion (OR 1.3; CI 0.7,2.7; p=0.4). Current CD4(+) cell counts were similar between those completing and not completing documentation (588 cells/μL and 604 cells/μL, respectively; p=0.7). The likelihood of ACP did not significantly differ with other comorbidities. Discussion: Less than 50% of middle-aged patients in HIV care had documented ACP. In particular, women and those with lower education were at greatest risk of non-completion and may need interventions to improve ACP. 相似文献
23.
Induction of NK activity in large granular lymphocyte leukemia: activation with anti-CD3 monoclonal antibody and interleukin 2 总被引:4,自引:0,他引:4
Large granular lymphocyte (LGL) leukemia is a rare disease characterized by clonal expansion of LGL associated with chronic neutropenia, multiple auto-antibodies, and occasionally polyarthritis. We studied cell surface antigen expression and functional activity of leukemic LGL from ten such patients. Using two-color flow cytometric analysis, we found that leukemic LGL from all ten patients expressed the CD3 and HNK-1 markers, while cells from only four patients expressed IgG Fc receptors (FcR). The LGL leukemic cells had little or no NK activity (defined as MHC-nonrestricted cytotoxicity against K562 target cells); however, NK activity could be induced in leukemic LGL by in vitro treatment with as little as 0.05 microgram/mL of anti-CD3 monoclonal antibody. Cell sorting experiments demonstrated that NK activity was induced in CD3+ leukemic LGL (either CD3+, HNK-1+ or CD3+, FcR+) with anti-CD3 monoclonal antibody but not in normal CD3+, FcR- T cells. Treatment with purified interleukin 2 (IL 2) also caused direct activation of some CD3+ leukemic LGL. Despite induction with anti-CD3 MAb or IL 2, activated leukemic LGL did not proliferate or express high density IL 2 receptors detectable by cell sorter analysis. Treatment with alpha interferon had minimal effect on NK activity of LGL leukemic cells. These results suggest that leukemic LGL may provide a useful model for examining the signals required for LGL maturation and activation. 相似文献
24.
CD3+ large granular lymphocyte (LGL) leukemia is a disease of unknown etiology characterized by clonal proliferation of T cells that usually express T-cell receptor (TCR) alpha beta heterodimers. The purpose of this study was to identify the variable (V), joining (J), and diversity (D) region TCR beta-chain genes expressed by CD3+ LGL leukemic cells in an attempt to gain insights into the etiology of this disorder. Twelve patients with LGL leukemia were studied, including seven with both LGL leukemia and rheumatoid arthritis (RA). RA is also a disease of unknown etiology that occurs frequently in patients with LGL leukemia. Clonally expanded T cells that express specific TCR V beta genes have been identified in fluid and tissue specimens from the joints of patients with RA. In this study, V beta expression was determined by PCR using a panel of 22 unique V beta primers to amplify cDNA prepared from peripheral blood mononuclear cells (PBMC). A dominant V beta gene product was readily apparent in all patients. To confirm that the dominant V beta gene originated from a clonal expansion, DNA fragments corresponding to the dominant V beta genes were subcloned into plasmids and independently isolated recombinants were sequenced. V-D-J region sequences that occurred repeatedly indicated clonality. The V beta and J beta genes expressed by the leukemic cells showed a pattern of distribution that followed the frequency with which these genes are represented in the peripheral blood. The residues corresponding to the third complementarity-determining region of the TCR beta chain were different in all cases. A specific pattern of VDJ usage was not identified for those patients with both LGL leukemia and RA; however, utilization of V beta-6 by LGL clones (N = 3) was observed only in the setting of RA. These data suggest that leukemic CD3+ LGL cells have been clonally transformed in a random fashion with respect to the TCR beta chain. 相似文献
25.
This study examined the effects of cyclical etidronate, when used in
routine clinical practice, on the prevention of fracture. Information was
obtained from 550 general practices in the UK that provide their medical
records to the General Practice Research Database. A total of 7977 patients
taking cyclical etidronate treatment and 7977 age-, sex- and
practice-matched control patients with a diagnosis of osteoporosis were
analysed. People taking cyclical etidronate had a significantly reduced
risk of non-vertebral fracture (by 20%) and of hip fracture (by 34%)
relative to the osteoporosis control patients. The relative risk of
non-vertebral fracture was 0.80 (95% confidence interval 0.70-0.92), that
of hip fracture 0.66 (0.51-0.85) and that of wrist fracture 0.81
(0.58-1.14). When fracture incidence rates were compared between the two
groups, the rate of non-vertebral, hip and wrist fracture decreased
significantly (P < 0.05) with increasing etidronate exposure. The
results of this study complement and extend clinical observations
supporting the anti-fracture efficacy of cyclical etidronate therapy.
相似文献
26.
Three distinct clinical syndromes occur in patients with increased numbers of circulating LGL. Patients with T-LGL leukemia have clonal proliferations of CD3+ LGL typically associated with chronic neutropenia and autoimmune features. NK-LGL leukemia is characterized by clonal CD3- LGL proliferation with an acute clinical presentation marked by massive hepatosplenomegaly and systemic illness. However, most patients with increased numbers of CD3- LGL do not have clinical features of NK-LGL leukemia and have a chronic clinical course. X- linked gene analyses have supported a polyclonal LGL lymphocytosis in this syndrome. Further studies are needed to determine whether clonal progression can occur in these patients. 相似文献
27.
28.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
29.
Prevention of degradation of human polymorphonuclear leukocyte proteins by diisopropylfluorophosphate 总被引:27,自引:0,他引:27
Proteases can complicate the characterization of proteins from cells, especially human polymorphonuclear leukocytes (PMN), which contain abundant neutral proteases. We tested the ability of agents to inhibit proteolysis, with special reference to the subunit polypeptides of the contractile proteins actin, myosin, and actin-binding protein (ABP). Phenylmethylsulfonyl fluoride (PMSF), O-phenanthroline, EGTA, EDTA, N- ethylmaleimide, alone or in combinations, failed to prevent extensive proteolysis of the PMN proteins during solubilization of cells with dodecyl sulfate. These inhibitors and also alpha-1-antitrypsin and soybean trypsin inhibitor similarly could not prevent proteolysis during homogenization of cells in cold isosomolar sucrose. Treatment of PMN with greater than or equal to mM diisopropylfluorophosphate (DFP) prior to solubilization or homogenization markedly inhibited proteolysis. PMSF and DFP were equally effective in inhibiting proteolysis in PMN extracts, suggesting that the efficacy of DFP may result from its permeation of intact cells and granules before barriers are disrupted by detergents or homogenization. Treatment of PMN with DFP under conditions inhibiting proteolysis did not affect their rate of phagocytosis. We recommend the use of DFP in future studies correlating functions and protein structure of PMN. 相似文献
30.