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401.

Objectives

The aim of the study was to quantify the benefits (life expectancy gains) and risks (efavirenz‐related teratogenicity) associated with using efavirenz in HIV‐infected women of childbearing age in the USA.

Methods

We used data from the Women's Interagency HIV Study in an HIV disease simulation model to estimate life expectancy in women who receive an efavirenz‐based initial antiretroviral regimen compared with those who delay efavirenz use and receive a boosted protease inhibitor‐based initial regimen. To estimate excess risk of teratogenic events with and without efavirenz exposure per 100 000 women, we incorporated literature‐based rates of pregnancy, live births, and teratogenic events into a decision analytic model. We assumed a teratogenicity risk of 2.90 events/100 live births in women exposed to efavirenz during pregnancy and 2.68/100 live births in unexposed women.

Results

Survival for HIV‐infected women who received an efavirenz‐based initial antiretroviral therapy (ART) regimen was 0.89 years greater than for women receiving non‐efavirenz‐based initial therapy (28.91 vs. 28.02 years). The rate of teratogenic events was 77.26/100 000 exposed women, compared with 72.46/100 000 unexposed women. Survival estimates were sensitive to variations in treatment efficacy and AIDS‐related mortality. Estimates of excess teratogenic events were most sensitive to pregnancy rates and number of teratogenic events/100 live births in efavirenz‐exposed women.

Conclusions

Use of non‐efavirenz‐based initial ART in HIV‐infected women of childbearing age may reduce life expectancy gains from antiretroviral treatment, but may also prevent teratogenic events. Decision‐making regarding efavirenz use presents a trade‐off between these two risks; this study can inform discussions between patients and health care providers.  相似文献   
402.
Noel E. Eldridge  MS    Susan S. Woods  BS  MBA    Robert S. Bonello  MD    Kay Clutter  RN  BSN  MBA    LeAnn Ellingson  BSN  RN  CIC    Mary Ann Harris  RN  BSN  CIC    Barbara K. Livingston  RN  BSN  MPH  CIC    James P. Bagian  MD  PE    Linda H. Danko  RN  MSN    Edward J. Dunn  MD  MPH  MBA  MPA    Renee L. Parlier  BSN  MPA    Cheryl Pederson  RN  BA    Kim J. Reichling  MBA    Gary A. Roselle  MD    Steven M. Wright  PhD 《Journal of general internal medicine》2006,21(S2):S35-S42
BACKGROUND: The Centers for Disease Control and Prevention (CDC) Guideline for Hand Hygiene in Health Care Settings was issued in 2002. In 2003, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) established complying with the CDC Guideline as a National Patient Safety Goal for 2004. This goal has been maintained through 2006. The CDC's emphasis on the use of alcohol-based hand rubs (ABHRs) rather than soap and water was an opportunity to improve compliance, but the Guideline contained over 40 specific recommendations to implement.
OBJECTIVE: To use the Six Sigma process to examine hand hygiene practices and increase compliance with the CDC hand hygiene recommendations required by JCAHO.
DESIGN: Six Sigma Project with pre-post design.
PARTICIPANTS: Physicians, nurses, and other staff working in 4 intensive care units at 3 hospitals.
MEASUREMENTS: Observed compliance with 10 required hand hygiene practices, mass of ABHR used per month per 100 patient-days, and staff attitudes and perceptions regarding hand hygiene reported by questionnaire.
RESULTS: Observed compliance increased from 47% to 80%, based on over 4,000 total observations. The mass of ABHR used per 100 patient-days in 3 intensive care units (ICUs) increased by 97%, 94%, and 70%; increases were sustained for 9 months. Self-reported compliance using the questionnaire did not change. Staff reported increased use of ABHR and increased satisfaction with hand hygiene practices and products.
CONCLUSIONS: The Six Sigma process was effective for organizing the knowledge, opinions, and actions of a group of professionals to implement the CDC's evidence-based hand hygiene practices in 4 ICUs. Several tools were developed for widespread use.  相似文献   
403.
Acid-sensing ion channel 3 (ASIC3) is highly expressed on sensory neurons that innervate heart and skeletal muscle and, therefore, is proposed to detect lactic acidosis and to transduce angina and muscle ischemic pain. A difficulty with this idea is that ASIC3 rapidly desensitizes. How can a desensitizing ion channel mediate a persisting sensation such as angina? Here, we show that rat ASIC3 produces a sustained current within the limited range of extracellular pH (7.3 to 6.7) that occurs during cardiac and skeletal muscle ischemia; experiments use patch clamp on transfected cell lines and on fluorescently tagged sensory neurons that innervate rat heart. No such sustained current occurs with ASIC1a (either as homomers or 1a/3 heteromers), whereas ASIC2a/3 heteromers give much larger currents than ASIC3 homomers. The sustained current persists even over tens of minutes because it is caused by a region of pH where there is overlap between inactivation and activation of the channel. Lactate, an anaerobic metabolite, allows the current to activate at slightly more basic pH. Surprisingly, amiloride, which blocks ASICs when they are activated at lower pH, increases ASIC3 current evoked at pH 7.0. Cardiac sensory neurons exhibit a small, perfectly sustained current when pH changes from 7.4 to 7.0. At least some of this current is carried by ASICs because the current is increased by both Zn(2+), an ASIC modulator, and amiloride. We suggest that this sustained mode is the most relevant form of ASIC3 gating for triggering angina and other ischemic pain.  相似文献   
404.
Recombinant human granulocyte-macrophage (GM) colony-stimulating factor (GM-CSF), G-CSF, and interleukin-3 (IL-3) labeled with 125I were used to study the characteristics and distribution of receptors for these factors on in vitro cell lines and on cells from patients with acute nonlymphocytic leukemia (ANL) and acute lymphocytic leukemia (ALL). Receptors for GM-CSF and G-CSF were restricted to a subset of myelomonocytic cell lines whereas IL-3 receptors were also found on pre- B- or early B-cell lines. Receptors for all three CSFs were broadly distributed on ANL cells, with considerable variability in levels of expression. Measurement of the colony-forming ability of ANL cells in response to the CSFs showed that there was no direct correlation between the ability of the cells to respond to a growth factor and the absolute number of receptors expressed for that growth factor. Binding of radiolabeled IL-3 and GM-CSF to ANL cells produced complex biphasic curves. Further analysis showed that both IL-3 and GM-CSF were able to partially compete for specific binding of the heterologous radiolabeled ligand to cells from several ANL patients, suggesting that heterogeneity may exist in human CSF receptors. These results provide new insights into the complex role that CSFs may play in ANL.  相似文献   
405.
Summary. Background: Tissue factor (TF) is the most relevant physiological trigger of thrombosis. Additionally TF is a transmembrane receptor with cell signaling functions. Objectives: The aim of this study was to investigate TF subcellular localization, function and signaling in human coronary artery smooth muscle cell migration. Methods: Coronary arteries and primary cultures of vascular smooth muscle cells (HVSMC) were obtained from human explanted hearts. Wound repair and Boyden chamber assays were used to measure migration in vitro. TF‐pro‐coagulant activity (TF‐PCA) was measured in extracted cellular membranes. Analysis of TF distribution was performed by confocal microscopy. A nucleofector device was used for TF and protease activated receptor 2 (PAR2) silencing. mRNA levels were analyzed by RT‐PCR. Results: In migrating HVSMC TF translocates to the leading edge of the cells showing an intense patch‐like staining in the lamellipodia. In the migrating front TF colocalizes with filamin (FLN) in the polarized lipid rafts. TF‐PCA was increased in migrating cells. Silencing of the TF gene inhibits RSK‐induced FLN‐Ser‐2152 phosphorylation, down‐regulates CDC42, RhoA, and Rac1 protein expression and significantly inhibits cell migration. Silencing PAR2 also inhibits cell migration; however, silencing both TF and PAR2 induces a significantly higher effect on migration. Smooth muscle cells expressing TF have been identified in non‐lipid‐rich human coronary artery atherosclerotic plaques. Conclusions: TF translocates to the cell front in association with cytoskeleton proteins and regulates HVSMC migration by mechanisms dependent and independent of factor (F)VIIa/PAR2. These results extend the functional role of TF to smooth muscle cell trafficking in vessel wall remodeling.  相似文献   
406.
407.
Stage I and II follicular non-Hodgkin's lymphoma (NHL) is clinically defined as a localized disease. To study the possibility that this disease is in fact disseminated, we used the sensitive polymerase chain reaction (PCR) method using translocation (14;18) as marker. Samples from 21 patients who were clinically diagnosed with stage I or II follicular NHL were analyzed for the presence of t(14;18)-positive cells using PCR. We analyzed (1) the diagnostic lymph node biopsy and (2) the peripheral blood or bone marrow samples from these patients. Translocation (14;18) cells were detected in the diagnostic lymph node biopsies of 12 patients. In 9 of these patients, t(14;18)-positive cells were detected in peripheral blood and/or bone marrow samples at diagnosis and/or after therapy. Thus, in 75% of the follicular NHL patients carrying the t(14;18) as a marker for lymphoma cells, t(14;18)- positive cells were detected in peripheral blood and bone marrow at diagnosis and after therapy. Our results show that t(14;18)-positive cells can be detected in the circulation of patients with stage I and II follicular NHL, indicating that, although diagnosed as localized, the disease is disseminated.  相似文献   
408.
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