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991.
Mary Courtney PhD Helen Edwards PhD Anne Chang PhD Anthony Parker PhD Kathleen Finlayson MN Kyra Hamilton BPsych 《Journal of the American Geriatrics Society》2009,57(3):395-402
OBJECTIVES: To evaluate the effect of an exercise‐based model of hospital and in‐home follow‐up care for older people at risk of hospital readmission on emergency health service utilization and quality of life. DESIGN: Randomized controlled trial. SETTING: Tertiary metropolitan hospital in Australia. PARTICIPANTS: One hundred twenty‐eight patients (64 intervention, 64 control) with an acute medical admission, aged 65 and older and with at least one risk factor for readmission (multiple comorbidities, impaired functionality, aged ≥75, recent multiple admissions, poor social support, history of depression). INTERVENTION: Comprehensive nursing and physiotherapy assessment and individualized program of exercise strategies and nurse‐conducted home visit and telephone follow‐up commencing in the hospital and continuing for 24 weeks after discharge. MEASUREMENTS: Emergency health service utilization (emergency hospital readmissions and visits to emergency department, general practitioner (GP), or allied health professional) and health‐related quality of life (Medical Outcomes Study 12‐item Short Form Survey (SF‐12v2?) collected at baseline and 4, 12, and 24 weeks after discharge. RESULTS: The intervention group required significantly fewer emergency hospital readmissions (22% of intervention group, 47% of control group, P=.007) and emergency GP visits (25% of intervention group, 67% of control group, P<.001). The intervention group also reported significantly greater improvements in quality of life than the control group as measured using SF‐12v2? Physical Component Summary scores (F (3, 279)=30.43, P<.001) and Mental Component Summary scores (F (3, 279)=7.20, P<.001). CONCLUSION: Early introduction of an individualized exercise program and long‐term telephone follow‐up may reduce emergency health service utilization and improve quality of life of older adults at risk of hospital readmission. 相似文献
992.
Evaluation of a portable recording device (ApneaLink?) for case selection of obstructive sleep apnea
Hui Chen Alan A. Lowe Yuxing Bai Peter Hamilton John A. Fleetham Fernanda R. Almeida 《Sleep & breathing》2009,13(3):213-219
Objective This study was designed to assess the sensitivity and specificity of a portable sleep apnea recording device (ApneaLink™) using standard polysomnography (PSG) as a reference and to evaluate the possibility of using the ApneaLink™ as a case selection technique for patients with suspected obstructive sleep apnea (OSA).
Materials and methods Fifty patients (mean age 48.7 ± 12.6 years, 32 males) were recruited during a 4-week period. A simultaneous recording of both
the standard in-laboratory PSG and an ambulatory level 4 sleep monitor (ApneaLink™) was performed during an overnight study for each patient. PSG sleep and respiratory events were scored manually according
to standard criteria. ApneaLink™ data were analyzed either with the automated computerized algorithm provided by the manufacturer following the American
Academy of Sleep Medicine standards (default setting DFAL) or The University of British Columbia Hospital sleep laboratory
standards (alternative setting, ATAL). The ApneaLink respiratory disturbance indices (RDI), PSG apnea–hypopnea indices (AHI),
and PSG oxygen desaturation index (ODI) were compared.
Results The mean PSG-AHI was 30.0 ± 25.8 events per hour. The means of DFAL-RDI and ATAL-RDI were 23.8 ± 21.9 events per hour and
29.5 ± 22.2 events per hour, respectively. Intraclass correlation coefficients were 0.958 between PSG-AHI and DFAL-RDI and
0.966 between PSG-AHI and ATAL-RDI. Receiver operator characteristic curves were constructed using a variety of PSG-AHI cutoff
values (5, 10, 15, 20, and 30 events per hour). Optimal combinations of sensitivity and specificity for the various cutoffs
were 97.7/66.7, 95.0/90.0, 87.5/88.9, 88.0/88.0, and 88.2/93.9, respectively for the default setting. The ApneaLink™ demonstrated the best agreement with laboratory PSG data at cutoffs of AHI ≥ 10. There were no significant differences among
PSG-AHI, DFAL-RDI, and ATAL-RDI when all subjects were considered as one group. ODI at 2%, 3%, and 4% desaturation levels
showed significant differences (p < 0.05) compared with PSG-AHI, DFAL-RDI, and ATAL-RDI for the entire group.
Conclusion The ApneaLink™ is an ambulatory sleep monitor that can detect OSA and/or hypopnea with acceptable reliability. The screening and diagnostic
capability needs to be verified by further evaluation and manual scoring of the ApneaLink™. It could be a better choice than traditional oximetry in terms of recording respiratory events, although severity may be
under- or overestimated. 相似文献
993.
Matthews DC; Appelbaum FR; Eary JF; Fisher DR; Durack LD; Bush SA; Hui TE; Martin PJ; Mitchell D; Press OW 《Blood》1995,85(4):1122-1131
In an attempt to decrease the relapse rate after bone marrow transplantation (BMT) for advanced acute leukemia, we initiated studies using 131I-labeled anti-CD45 antibody (BC8) to deliver radiation specifically to hematopoietic tissues, followed by a standard transplant preparative regimen. Biodistribution studies were performed in 23 patients using 0.5 mg/kg trace 131I-labeled BC8 antibody. The BC8 antibody was cleared rapidly from plasma with an initial disappearance half-time of 1.5 +/- 0.2 hours, presumably reflecting rapid antigen- specific binding. The mean radiation absorbed doses (cGy/mCi131I administered) were as follows: marrow, 7.1 +/- 0.8; spleen, 10.8 +/- 1.4; liver, 2.7 +/- 0.2; lungs, 2.1 +/- 0.1; kidneys, 0.7 +/- 0.1; and total body, 0.4 +/- 0.03. Patients with acute myelogenous leukemia (AML) in relapse had a higher marrow dose (11.4 cGy/mCi) than those in remission (5.2 cGy/mCi; P = .001) because of higher uptake and longer retention of radionuclide in marrow. Twenty patients were treated with a dose of 131I estimated to deliver 3.5 Gy (level 1) to 7 Gy (level 3) to liver, with marrow doses of 4 to 30 Gy and spleen doses of 7 to 60 Gy, followed by 120 mg/kg cyclophosphamide (CY) and 12 Gy total body irradiation (TBI). Nine of 13 patients with AML or refractory anemia with excess blasts (RAEB) and two of seven with acute lymphocytic leukemia (ALL) are alive disease-free at 8 to 41 months (median, 17 months) after BMT. Toxicity has not been measurably greater than that of CY/TBI alone, and the maximum tolerated dose has not been reached. This study demonstrates that with the use of 131I-BC8 substantially greater doses of radiation can be delivered to hematopoietic tissues as compared with liver, lung, or kidney, which may improve the efficacy of marrow transplantation. 相似文献
994.
Interleukin-8 induces rapid mobilization of hematopoietic stem cells with radioprotective capacity and long-term myelolymphoid repopulating ability 总被引:10,自引:5,他引:10
Interleukin-8 (IL-8) belongs to a family of chemoattractant cytokines involved in chemotaxis and activation of neutrophils. As in vivo administration of IL-8 induces granulocytosis and the release of immature white blood cells into the circulation, we assessed a possible mobilizing effect of IL-8 on myeloid progenitor cells. IL-8 was administered at intraperitoneal doses ranging from 0.1 to 100 micrograms per mouse to female Balb/C mice (aged 8 to 12 weeks; weight, 20 to 25 g). Animals were killed at time intervals ranging from 1 to 240 minutes after IL-8 administration, and blood, bone marrow, and spleen cells were harvested. Injection of 30 micrograms IL-8 resulted in an increment from 25 +/- 9 to 418 +/- 299 granulocyte-macrophage colony-forming units (CFU-GM) per milliliter blood at 15 minutes after a single intraperitoneal injection. Sixty minutes after the injection of IL-8, the numbers of circulating CFU-GM per milliliter blood had almost returned to pretreatment values (82 +/- 39 CFU-GM per milliliter). A dose of 100 micrograms IL-8 per animal did not result in a further increment in the number of circulating CFU-GM. Transplantation of 5 x 10(5) blood-derived mononuclear cells (MNC) obtained at 30 minutes after IL-8 injection (30 micrograms) resulted in 69% survival of lethally irradiated (8.5 Gy) recipients at 60 days versus 22% for animals transplanted with an equal number of nonprimed blood-derived MNC. Transplantation of 1.5 x 10(6) MNC obtained from IL- 8-treated donors resulted in 100% survival. Six months after transplantation, female recipients of MNC derived from IL-8-treated male donors were killed, and chimerism was determined in bone marrow, spleen, and thymus using a Y chromosome-specific probe and fluorescent in situ hybridization (FISH). The majority of bone marrow, spleen, and thymus cells (83% +/- 25%, 89% +/- 5%, and 64 +/- 28%, respectively) consisted of Y chromosome-positive cells, showing that the IL-8- mobilized cells had myelolymphoid repopulating ability. We conclude that IL-8 is a cytokine that induces rapid mobilization of progenitor cells and pluripotent stem cells that are able to rescue lethally irradiated mice and that are able to completely and permanently repopulate host hematopoietic tissues. 相似文献
995.
Graft-versus-host disease (GVHD) is currently encountered after bone marrow transplantation and transfusion. GVHD associated with transfusion (TA-GVHD) in apparently immunocompetent recipients has been recently reported with increasing frequency. A consistent finding in many of these cases is that the recipient received blood from a donor homozygous for one of the recipient's HLA haplotypes. However, the observed frequency of TA-GVHD is much lower than the estimated probability of this donor/recipient combination. The potential role of recipient immune responses in controlling TA-GVHD was investigated using an analogous murine model in which GVHD is induced by the injection of parental lymphoid cells into unirradiated F1 hybrid recipients. The effect of various immune manipulations of the recipient of GVHD induction was assessed by determining the number of donor lymphoid cells required to induce GVHD responses. Whereas depletion of recipient CD4+ cells increased the number of donor cells needed to induce GVHD, depletion of recipient CD8+ and natural killer cells resulted in fewer donor cells being needed to induce a GVHD response. These studies suggest a central role for functioning recipient CD8 and natural killer cells in the down-regulation of TA-GVHD development in recipients. 相似文献
996.
Antineutrophil cytoplasm autoantibodies against bactericidal/permeability-increasing protein in inflammatory bowel disease. 总被引:6,自引:1,他引:6 下载免费PDF全文
R S Walmsley M H Zhao M I Hamilton A Brownlee P Chapman R E Pounder A J Wakefield C M Lockwood 《Gut》1997,40(1):105-109
BACKGROUND: Bactericidal/permeability-increasing protein (BPI), a constituent of primary neutrophil granules, is a potent natural antibiotic and an antineutrophil cytoplasm antibody (ANCA) antigen in cases of vasculitis in which the target antigen is neither myeloperoxidase (MPO) nor proteinase-3 (PR3). AIM: To investigate BPI as a possible target antigen for ANCAs in inflammatory bowel disease. METHODS: ANCAs were detected by routine immunofluorescence (IIF) and solid phase enzyme linked immunosorbent assay (ELISA) performed for antibodies to the purified neutrophil granule proteins; MPO, PR3, cathepsin-G, lactoferrin, and BPI in serum samples from 88 patients with inflammatory bowel disease (36 with Crohn's disease, 52 with ulcerative colitis). Thirty patients with bacterial enteritis acted as controls. RESULTS: Significantly more patients with ulcerative colitis were ANCA positive by IIF (60%) than patients with Crohn's disease (28%) or infectious enteritis (23%) (p < 0.001). IgG anti-BPI antibodies were present in 29% of patients with ulcerative colitis, 14% of patients with Crohn's disease, and 23% of patients with infectious enteritis, occurring in 44% of those patients with inflammatory bowel disease who were ANCA positive by IIF. Antibodies to other ANCA antigens were rare. The presence of ANCAs was not related to either disease activity or extent; presence of anti-BPI antibodies was significantly related to both a lower serum albumin concentration (p = 0.001) and a higher erythrocyte sedimentation rate (p = 0.02) in patients with ulcerative colitis, and to colonic involvement in patients with Crohn's disease (p = 0.01). CONCLUSION: BPI is a significant minority target antigen for ANCAs in inflammatory bowel disease that seems related to colonic Crohn's disease and disease activity in ulcerative colitis. Anti-BPI antibodies occur in infectious enteritis. 相似文献
997.
E A Rich M Torres E Sada C K Finegan B D Hamilton Z Toossi 《Tubercle and lung disease》1997,78(5-6):247-255
SETTING: Although nitric oxide (NO) is a major proximate mediator of microbicidal activity in murine macrophages against intracellular pathogens including mycobacteria, its production by and effector role in human macrophages is not clear. OBJECTIVE: To determine the capacity of Mycobacterium tuberculosis (MTB) to stimulate NO in human monocytes (MN) and alveolar macrophages (AM) and to assess the relationship between NO production and intracellular growth of MTB. DESIGN: NO production (measured as nitrite) by MTB (H37Ra)-infected macrophages and intracellular growth of MTB were measured in cells from 17 healthy subjects. RESULTS: MTB (5:1, MTB:cells) stimulated little to no NO by MN, but induced NO in AM at days 4 and 7 after infection. There was, however, variability in the response by AM to MTB: among seven subjects MTB-induced NO was low (4 +/- 2 microM, mean +/- SE); six subjects were moderate (56 +/- 11); four subjects were high (502 +/- 167). NO synthase inhibitors inhibited the production of NO by AM but did not significantly affect the intracellular growth of MTB, although a trend towards increased intracellular growth was seen on day 4 of culture. Intracellular growth of MTB in AM from low NO producers was significantly higher than that in AM from moderate NO producers, P < or = 0.05. Inducible NO synthase (iNOS) mRNA by RT-PCR was constitutively expressed by both MN and AM, but was further stimulated by MTB in AM > MN; MTB-induced iNOS protein was present in both MN and AM by Western blot analysis. CONCLUSION: Thus, MTB-infected human AM are capable of producing NO and NO production correlates with intracellular growth inhibition of MTB in AM suggesting that NO may serve either directly or indirectly as a mycobactericidal mediator in human tissue macrophages. 相似文献
998.
Genetic epidemiology of mutated K-ras proto-oncogene, altered suppressor genes, and microsatellite instability in colorectal adenomas 总被引:8,自引:0,他引:8 下载免费PDF全文
BACKGROUND: The genetic epidemiology of colorectal adenomas has not been studied prospectively in colonoscopy patients without cancer. AIMS: To study genetic alterations in colorectal adenomas and correlate these with patient demographics and adenoma characteristics. METHODS: Mutations and allelic deletions in 201 adenomas from 60 patients were compared with demographic features, adenoma characteristics, and family history. RESULTS: The most common alteration was K-ras proto-oncogene mutation, present in 35% of adenomas and 65% of patients. Patients 65 years of age and older had a decreased probability of K-ras mutations (26% versus 45%). Overexpression of p53 gene product was present in only 6% of adenomas but was more frequent in villous or tubulovillous adenomas (19% versus 3%). Allelic loss of chromosome 18q was present in only 2% of adenomas and was significantly less frequent than p53 overexpression. DNA replication errors (RER) were present in 7% of adenomas and 15% of patients, including multiple adenomas in four patients (two with hereditary non-polyposis colorectal cancer syndrome). Only 36% of RER positive adenomas had alteration of BAT-26 alleles, none had alteration of BAT-25, and only one (8%) had mutation in the transforming growth factor beta type II receptor gene. RER positive adenomas were more likely to have a K-ras mutation. In patients with multiple adenomas, there was concordance of p53 overexpression and RER but not of K-ras mutations. CONCLUSIONS: Genetic progression in colorectal adenomas is heterogeneous, involving factors related to patient age and the presence of RER for the occurrence of ras mutations, but different intraindividual characteristics for the occurrence of p53 alterations and RER. 相似文献
999.
H G Pollock J R Kimmel J W Hamilton J B Rouse K E Ebner V Lance A B Rawitch 《General and comparative endocrinology》1987,67(3):375-382
Insulin and a 36-residue peptide with homology to pancreatic polypeptide (PP) were isolated from the endocrine pancreas of the alligator gar (Lepisosteus spatula), a ganoid fish, by gel filtration and HPLC. Heterologous radioimmunoassays were used to detect insulin-like and PP-like immunoreactivities during purification of the two peptides. The sequence of the 36-amino acid peptide containing a C-terminal tyrosinamide was identical at 31 of 36 positions to porcine neuropeptide Y (NPY). The amino acid sequence of this peptide is YPPKPENPGEDAPPEELAKYYSALRHYINLITRQRY-NH2. The second peptide, gar insulin, contains 52 amino acid residues and is composed of a 21-residue A chain and a 31-residue B chain. The sequence of the A chain is GIVEQCCHKPCTIYELENYCN. The sequence of the B chain is AANQHLCGSHLVEALYLVCGEKGFFYNPNKV. 相似文献
1000.
Treatment of essential hypertension with PN 200-110 (isradipine) 总被引:1,自引:0,他引:1
B P Hamilton 《The American journal of cardiology》1987,59(3):141B-145B
The safety and antihypertensive efficacy of PN 200-110 (isradipine), a novel calcium antagonist, are discussed in a preliminary report of double-blind, multicenter, controlled, phase III clinical trials for essential hypertension. Patients who qualified for entry after a 3 week placebo-washout period were enrolled in 1 of 5 studies; 2 studies were placebo controlled; 3 studies evaluated PN 200-110 against 1 of 3 active controls: hydrochlorothiazide (HCTZ) propranolol or prazosin. A separate study assessing the effects of PN 200-110 in combination with HCTZ versus propranolol plus HCTZ is also discussed. Compared with placebo, PN 200-110 decreased mean supine systolic and diastolic blood pressures by 20/16 mm Hg versus 4/6 mm Hg. Compared with placebo and active control drugs, PN 200-110 normalized supine diastolic blood pressure to less than or equal to 90 mm Hg in 72% of patients, versus 13% in the placebo group, 74% in the HCTZ group, 45% in the propranolol group and 69% in the prazosin group. In the ability to decrease diastolic blood pressure by greater than or equal to 10 mm Hg, PN 200-110 compared favorably to prazosin (81% vs 81%), and was superior to HCTZ (81% vs 61%) and propranolol (81% vs 36%). In combination with HCTZ, PN 200-110 exerted as great an antihypertensive effect as propranolol plus HCTZ. Long-term therapy with PN 200-110 was also effective. Supine systolic and diastolic blood pressures decreased a mean of 15/13 mm Hg at 3 months, and 18/20 mm Hg at 12 months. PN 200-110 is well tolerated with relatively few adverse effects reported. 相似文献