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We have previously shown that normal-density human peripheral blood eosinophils transcribe and translate mRNA for granulocyte-macrophage colony-stimulating factor (GM-CSF) and that the intracellular distribution was granular as assessed by light microscopy immunocytochemistry. The present study was conducted to confirm this apparent association between GM-CSF and the crystalloid granule using a subcellular fractionation method for human eosinophils and immunogold electron microscopy (EM). Highly purified (> 99%, by negative selection using anti-CD16 immunomagnetic microbeads) human peripheral blood eosinophils were obtained from four asthmatic subjects (not taking systemic medication), homogenized and density fractionated (5 x 10(7) cells/subject) on linear Nycodenz gradients. Twenty-four fractions were collected from each cell preparation and analyzed for marker enzyme activities as well as total protein. Dot blot analysis with specific monoclonal antibodies (MoAbs) was used to detect the eosinophil granule proteins major basic protein (MBP) and eosinophil cationic protein (ECP). An anti-CD9 MoAb was used as an eosinophil plasma membrane marker. Lactate dehydrogenase (LDH) was used as a cytosolic marker. Immunoreactivity for GM-CSF was detected by a specific enzyme-linked immunosorbent assay using a polyclonal antihuman GM-CSF antibody and confirmed by dot blot. GM-CSF coeluted with the cellular fractions containing granule markers (MBP, ECP, eosinophil peroxidase, hexosaminidase, and arylsulphatase), but not those containing cytoplasm (LDH+) or membrane (CD9+) markers. EM examination of pooled fractions associated with the peak of GM-CSF immunoreactivity confirmed that they contained crystalloid and small granules, but not plasma membrane. In addition, quantification, using immunogold labeling with an anti/GM-CSF MoAb, indicated preferential localization of gold particles over the eosinophil granule cores of intact cells. Thus, our results indicate that GM-CSF resides as a granule-associated, stored mediator in unstimulated human eosinophils.  相似文献   
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Objective

This study examined if ongoing support delivered by telephone following pulmonary rehabilitation (PR) assisted chronic obstructive pulmonary disease (COPD) patients to maintain health outcomes.

Methods

Phase one (n = 79) compared post-rehabilitation telephone-based support delivered by peers compared to usual care (UC). The second phase (n = 168) compared post-rehabilitation support from peer educators, respiratory therapists (RT), or UC. Primary outcome variables were St. George's Respiratory Questionnaire (SGRQ) total score and the six minute walk test (6MWT). Measures were obtained at baseline, immediately following PR, and six-months post PR.

Results

Six-month follow-up data for phase one was collected for 66 COPD patients (n = 35 peer support, n = 31 UC) and 142 for phase two (n = 42 peer support, n = 52 RT support, n = 48 UC). Per-protocol and intention to treat (ITT) analysis in both phases found no significant group by time differences for SGRQ or 6MWT.

Conclusion

Providing peer or RT support via telephone following PR was not more effective than UC for maintaining health outcomes.

Practice implications

There are concerns with using peers to provide ongoing support to COPD patients. Additionally, COPD patients require a higher level of care than telephone support can provide.  相似文献   
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The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine.  相似文献   
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Dental caries is the most prevalent human infection. It is a multifactorial disease in which the microbial composition of dental plaque plays a major role in the development of clinical symptoms. The bacteria most often implicated in the development of caries are that group of streptococci referred to as the mutans streptococci, in particular Streptococcus mutans and Streptococcus sobrinus. One approach to the prevention of caries is to reduce the numbers of mutans streptococci in plaque to a level insufficient to support demineralization of the tooth. In this study, zoocin A, a peptidoglycan hydrolase, combined with lauricidin, a cell membrane active lipid, was shown over a 72 h period to selectively suppress the growth of S. mutans in a triple species biofilm. Growth of the non-target species Streptococcus oralis and Actinomyces viscosus was not inhibited. In treated systems the amount of extracellular polysaccharide matrix produced was much reduced as determined by use of fluorescein isothiocyanate conjugated wheat germ agglutinin. The pH of treated biofilms remained above neutral as opposed to a value of 4.3 in untreated controls. We conclude that use of antimicrobial compounds that specifically target cariogenic bacteria should be further explored.  相似文献   
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BACKGROUND: Clear communication is imperative if teams in any industry expect to make improvements. An estimated 85% of errors across industries result from communication failures. PURPOSE: The purpose of this study was to evaluate and improve the effectiveness of communication during patient care rounds in the intensive care unit (ICU) using a daily goals form. DESIGN: We conducted a prospective cohort study in collaboration with the Volunteer Hospital Association (VHA), Institute for Healthcare Improvement (IHI), and Johns Hopkins Hospital's (JHH) 16-bed surgical oncology ICU. All patients admitted to the ICU were eligible. Main outcome variables were ICU length of stay (LOS) and percent of ICU residents and nurses who understood the goals of care for patients in the ICU. Baseline measurements were compared with measurements of understanding after implementation of a daily goals form. RESULTS: At baseline, less than 10% of residents and nurses understood the goals of care for the day. After implementing the daily goals form, greater than 95% of nurses and residents understood the goals of care for the day. After implementation of the daily goals form, ICU LOS decreased from a mean of 2.2 days to 1.1 days. CONCLUSION: Implementing the daily goals form resulted in a significant improvement in the percent of residents and nurses who understood the goals of care for the day and a reduction in ICU LOS. The use of the daily goals form has broad applicability in acute care medicine.  相似文献   
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