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71.
BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation.  相似文献   
72.
Controversy exists concerning the degree of microbial contamination associated with the us of rigid lumened medical devices, the efficacy of standard cleaning techniques used to remove pathogenic microorganisms from lumen channels, and whether patients are placed at risk of cross infection because of microbial contamination. In this study the level and types of microorganisms found on rigid lumened medical devices before and after cleaning in a hospital environment were investigated. The bioburden level after clinical use was found to be relatively low, ranging from 101 to 104 colony forming units (CFU) per device. After the instruments were cleaned, none of the devices studied contained bioburden levels greater than 104 CFU and 83% had bioburden levels less than or equal to 102 CFU. The bioburden present before cleaning was comprised of organisms derived from the handling of the device, from the hospital environment, and from the patient. The bioburden present after cleaning was comprised of organisms typically derived from the handling of the device and from the hospital environment. The level of bioburden per device was also related to the anatomic site where the device was used, with lower numbers of organisms found on devices exposed to sterile body sites and the respiratory tract.  相似文献   
73.
Neale  GA; Rehg  JE; Goorha  RM 《Blood》1995,86(8):3060-3071
Although the proto-oncogene rhombotin-2 (RBTN-2) is widely expressed in most tissues, it is not expressed in T cells. We investigated the potential for overexpression of RBTN-2 to cause tumors in T cells and other tissues by constructing transgenic mice that expressed RBTN-2 under control of the metallothionein-1 promoter. Despite overexpression of RBTN-2 in all tissues, transgenic mice developed T-cell tumors only, thus indicating that tumorigenesis caused by RBTN-2 is T-cell-specific. Thymic tumors were found between 37 and 71 weeks and were invariably associated with metastasis to nonlymphoid organs. Thymuses from apparently healthy transgenic mice were also examined. In some mice there was an 10-fold increase in the CD4-CD8- thymocyte subset, yet the total number of thymocytes was the same as that in wild-type mice. Thymic homeostasis was maintained by a compensatory reduction in the CD4+CD8+ subset. The expansion of CD4-CD8- thymocytes was associated with increased expression of RBTN-2 and with increased cell proliferation. No differences were found in the proportion of thymocytes undergoing apoptosis in transgenic mice. Furthermore, RBTN-2- induced expansion of CD4-CD8- cells did not block differentiation of these cells. Thymuses with 30% CD4-CD8- cells were essentially monoclonal, indicating that all thymic immunophenotypes were derived from a single clone. Overall, our data are consistent with the following scenario: (1) RBTN-2 expression in T cells causes selective and polyclonal proliferation of CD4-CD8- thymocytes accompanied by a compensatory decrease in other thymocyte subsets; (2) a clone with growth advantage and differentiation potential is selected and populates the thymus; and (3) this clone eventually breaches homeostasis of the thymus, accompanied or followed by metastasis to other organs.  相似文献   
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77.

Objective

To evaluate the impact of opioid controlled substance agreements (CSAs) enrollment on health care utilization.

Patients and Methods

We retrospectively evaluated health care utilization changes among 772 patients receiving long-term opioid therapy for chronic noncancer pain enrolled in a CSA between July 1, 2015, and December 31, 2015. We ascertained patient characteristics and utilization 12 months before and after CSA enrollment. Decreased utilization was defined as a decrease of 1 or more hospitalizations or emergency department visits and 3 or more outpatient primary and specialty care visits. Multivariate modeling assessed demographic characteristics associated with utilization changes.

Results

The 772 patients enrolled in an opioid CSA during the study period had a mean ± SD age of 63.5±14.9 years and were predominantly female, white, and married. The CSA enrollment was associated with decreased outpatient primary care visits (odds ratio [OR], 0.16; 95% CI, 0.14-0.19) and increased diagnostic radiology services (OR, 1.22; 95% CI, 1.02-1.47). After CSA enrollment, patients with greater comorbidity (Charlson Comorbidity Index score >3) were more likely to have reduced hospitalizations (adjusted OR, 2.8; 95% CI, 1.3-6.0; P=.008), reduced outpatient primary care visits (adjusted OR, 2.0; 95% CI, 1.2-3.2; P=.005), and reduced specialty care visits (adjusted OR, 2.0; 95% CI, 1.2-3.3; P=.006).

Conclusion

For patients receiving long-term opioid therapy for chronic noncancer pain, CSA enrollment is associated with reductions in primary care visits and increased radiologic service utilization. Patients with greater comorbidity were more likely to have reductions in hospitalizations, outpatient primary care visits, and outpatient specialty clinic visits after CSA enrollment. The observational nature of the study does not allow the conclusion that CSA implementation is the primary reason for these observed changes.  相似文献   
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Two double-blind, randomized, placebo-controlled, parallel group safety and efficacy studies included evaluation of the hypothalamic-pituitary-adrenal (HPA)-axis effects of concurrent treatment with intranasal and orally inhaled fluticasone propionate (FP). In the first study, patients with asthma who were > or =12 years of age were assigned randomly to receive twice-daily doses (either 88 or 220 microg) of orally inhaled FP delivered from a metered-dose inhaler (MDI). In the second study, patients were assigned randomly to receive either orally inhaled FP 250 microg or orally inhaled FP 250 microg/salmeterol 50 microg delivered via the Diskus device. In both studies, patients with rhinitis were allowed to continue the use of intranasal FP at their usual dosing. Treatment periods were 26 weeks and 12 weeks for the MDI and Diskus studies, respectively. HPA-axis effects were assessed using response to short cosyntropin stimulation testing. The number and percentage of patients with an abnormal cortisol response, defined as a morning plasma cortisol of <5 microg/dL, a poststimulation peak of <18 microg/dL, or a poststimulation rise of <7 microg/dL, were summarized in two subgroups: patients who used intranasal FP and those who did not. The concurrent administration of intranasal FP and orally inhaled FP via an MDI or Diskus or via Diskus with salmeterol was not associated with HPA-axis effects compared with orally inhaled FP alone. The results of these two studies suggest that concurrent use of intranasal FP with orally inhaled FP administered via MDI or Diskus for treatment of comorbid rhinitis and asthma does not increase the risk of HPA-axis abnormalities.  相似文献   
80.
A literature review was conducted to evaluate the available published data on sleep-related breathing disorders with a focus on obstructive sleep apnea (OSA) syndrome, nasal congestion, and snoring. The MEDLINE database was used to obtain pertinent reviews and articles. The pathophysiology of snoring, a partial blockage of the airway, and of apnea or total airway obstruction, is described. Contributing factors to the etiology of the OSA syndrome as well as current methods of diagnosis are discussed. Adverse systemic sequelae of the OSA syndrome, especially those pertaining to the cardiovascular and respiratory systems, are detailed. Treatment options, both nonsurgical and surgical, which are used to improve the quality of life of patients with these disorders, are presented also.  相似文献   
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