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61.
62.
BACKGROUND: Although iatrogenic injury poses a significant risk to hospitalized patients, detection of adverse events (AEs) is costly and difficult. METHODS: The authors developed a confidential reporting method for detecting AEs on a medicine unit of a teaching hospital. Adverse events were defined as patient injuries. Potential adverse events (PAEs) represented errors that could have, but did not result in harm. Investigators interviewed house officers during morning rounds and by e-mail, asking them to identify obstacles to high quality care and iatrogenic injuries. They compared house officer reports with hospital incident reports and patients’ medical records. A multivariate regression model identified correlates of reporting. RESULTS: One hundred ten events occurred, affecting 84 patients. Queries by e-mail (incidence rate ratio [IRR]=0.16; 95% confidence interval [95% CI], 0.05 to 0.49) and on days when house officers rotated to a new service (IRR=0.12; 95% CI, 0.02 to 0.91) resulted in fewer reports. The most commonly reported process of care problems were inadequate evaluation of the patient (16.4%), failure to monitor or follow up (12.7%), and failure of the laboratory to perform at test (12.7%). Respondents identified 29 (26.4%) AEs, 52 (47.3%) PAEs, and 29 (26.4%) other house officer-identified quality problems. An AE occurred in 2.6% of admissions. The hospital incident reporting system detected only one house officer-reported event. Chart review corroborated 72.9% of events. CONCLUSIONS: House officers detect many AEs among inpatients. Confidential peer interviews of front-line providers is a promising method for identifying medical errors and substandard quality. This research was supported in part by the CareGroup Center for Quality and Value. Preliminary data were presented at the Second Annenberg Conference on Enhancing Patient Safety and Reducing Errors in Health Care, Rancho Mirage, Calif, November 8–10, 1998, and an extended abstract published in the conference proceedings.  相似文献   
63.
Introduction and objectivesAsian desert dust has recently been recognized as a trigger for acute myocardial infarction. The inflow of dust from the Sahara into Spain impairs air quality due to an increase in particulate matter concentrations in the ambient air. The aim of the present study was to elucidate whether Saharan dust events are associated with the incidence of acute coronary syndrome (ACS) in patients living near North Africa, the major global dust source.MethodsWe prospectively collected data on hospitalizations due to ACS in 2416 consecutive patients from a tertiary care hospital (Canary Islands, Spain) from December 2012 to December 2017. Concentrations of particulate matter with an aerodynamic diameter 10 microns or smaller (PM10) and reactive gases were measured in the European Air Quality Network implemented in the Canary Islands. We applied the time-stratified case crossover design using conditional Poisson regression models to estimate the impact of PM10 Saharan dust events on the incidence of ACS.ResultsThe occurrence of Saharan dust events observed 0 to 5 days before the onset of ACS was not significantly associated with the incidence of ACS. Incidence rate ratios (IRR) of PM10 levels 1, 2, 3, 4 and 5 days before ACS onset (for changes in 10 μg/m3) were 1.27 (95%CI, 0.87-1.85), 0.92 (95%CI, 0.84-1.01), 0.74 (95%CI, 0.45-1.22), 0.98 (95%CI, 0.87-1.11), and 0.95 (95%CI, 0.84-1.06), respectively.ConclusionsExposure to Saharan desert dust is unlikely to be associated with the incidence of ACS.  相似文献   
64.
Asthma affects 300 million people worldwide and continues to be a major cause of morbidity and mortality. Disease relevant animal models of asthma are required for benchmarking of novel therapeutic mechanisms in comparison to established clinical approaches. We demonstrate that chronic exposure of mice to house dust mite (HDM) extract results in allergic airway inflammation, that can be significantly attenuated by therapeutic intervention with phosphodiesterase 4 inhibition and corticosteroid treatment. Female BALB/c mice were administered intranasally with HDM (Dermatophagoides pteronyssinus) extract daily for five weeks, and therapeutic intervention with anti-inflammatory treatment (dexamethasone 1 mg/kg subcutaneous once daily, prednisolone 10mg/kg orally twice daily, fluticasone 3, 10 and 30 microg intranasally twice daily, roflumilast 10 mg/kg orally twice daily and intranasally 10 and 30 microg twice daily) was initiated after three weeks of exposure. Chronic HDM extract exposure resulted in significant airway inflammation, demonstrated by bronchoalveolar lavage cell infiltration and lung tissue inflammatory gene expression by TaqMan low density array. Chronic steroid treatment significantly inhibited these parameters. In addition, roflumilast caused a significant reduction in airway inflammatory cell infiltration. We have demonstrated that chronic HDM-induced allergic inflammation can be significantly ameliorated by steroid treatment, and that phosphodiesterase 4 inhibition modulates inflammatory cell infiltration. Therefore, the murine HDM model may be a useful tool for evaluating new targets for the treatment of asthma.  相似文献   
65.
Abstract We report the case of a 44-year-old white man who presented with progressively worsening crampy abdominal pain and distention. Deterioration of his clinical picture along with leukocytosis and radiographic evidence of severe colonic dilation rendered exploratory laparotomy necessary. Greatly distended and inflamed transverse and descending colon were evident and an extended left colectomy was performed. Characteristic changes of leukocytoclastic vasculitis in the serosal and muscular layers of the resected colon were demonstrated at histopathologic examination. Systemic leukocytoclastic vasculitis, usually coexisting with Henoch-Schönlein purpura, commonly affects the small bowel with clinical evidence of ischemia or bleeding. Colon involvement is infrequently reported in the context of systemic disease. Isolated colonic leukocytoclastic vasculitis without extraintestinal manifestations is rare. A previously unreported case of localized leukocytoclastic vasculitis of the left colon resulting in the impressive presentation of megacolon, without the presence of any precipitating factor or associated systemic disease is presented here, with an overview of the related literature.  相似文献   
66.

Background

Several methods have been developed to detect allergen-specific IgE in sera. The passive IgE sensitization assay using human IgE receptor-expressing rat cell line RBL-2H3 is a powerful tool to detect biologically active allergen-specific IgE in serum samples. However, one disadvantage is that RBL-2H3 cells are vulnerable to high concentrations of human sera. Only a few human cultured cell lines are easily applicable to the passive IgE sensitization assay. However, the use of human induced pluripotent stem cells (iPSCs) to generate human mast cells (MCs) has not yet been reported.

Methods

The nuclear factor-kappa B (NF-κB)-responsive luciferase reporter gene was stably introduced into a human iPSC line 201B7, and the transfectants were induced to differentiate into MCs (iPSC-MCs). The iPSC-MCs were sensitized overnight with sera from subjects who were allergic to cedar pollen, ragweed pollen, mites, or house dust, and then stimulated with an extract of corresponding allergens. Activation of iPSC-MCs was evaluated by β-hexosaminidase release, histamine release, or luciferase intensity.

Results

iPSCs-MCs stably expressed high-affinity IgE receptor and functionally responded to various allergens when sensitized with human sera from relevant allergic subjects. This passive IgE sensitization system, which we termed the induced mast cell activation test (iMAT), worked well even with undiluted human sera.

Conclusions

iMAT may serve as a novel determining system for IgE/allergens in the clinical and research settings.  相似文献   
67.
Indoor aeroallergen exposures increased asthma symptoms in Caucasians, but their determinants and relationship to asthma and allergy in Asians are unclear. This study investigated exposures to cat, cockroach, and Blomia tropicalis allergens in 115 Hong Kong families with asthmatic children. Patients underwent exhaled nitric oxide and spirometric measurements. Home visits were made within 2 weeks during which parents completed a standardized questionnaire. Fel d 1, Bla g 2, and Blo t 5 in dust samples collected from patients' mattresses, bedroom floors, and living room floors were measured by immunoassays. These aeroallergens were only detectable in some homes (38–55% for Fel d 1; 9–21% for Bla g 2, and 7–14% for Blo t 5). The presence of cat and/or dog was a strong determinant for Fel d 1 in all indoor sites. The timing and frequency of bedding change was associated with Bla g 2 levels, whereas the timing of bedroom floor cleaning was a consistent factor for Blo t 5 levels. Asthmatic children in families with high allergen exposure were more likely to have ≥4 wheezing attacks in preceding 12 months and exercise‐induced wheezing than those with normal allergen exposure (P = 0.051 and 0.030, respectively). Mattress levels of all three allergens were also associated with severity of several allergy symptoms (P = 0.025–0.005). None of these aeroallergens correlated with exhaled nitric oxide and spirometric parameters. This study identifies determinants for cat, cockroach, and B. tropicalis levels in Hong Kong families with asthmatic children. These exposures are associated with severity of allergy symptoms. Pediatr. Pulmonol. 2011; 46:632–639. © 2011 Wiley‐Liss, Inc.  相似文献   
68.
目的调查合肥市3种不同生境中粉螨孳生状况及多样性。方法在5~8月粉螨孳生高峰期对合肥地区仓储食品、药材、日用品进行粉螨的采集、分类、计数、鉴定及数据分析。结果450份样本中335份检出粉螨,阳性率为74.4%;共检获粉螨26种,隶属于6科17属。多样性分析结果表明,3种不同生境中粉螨平均孳生密度(No./g)为11.01±6.42~23.75±7.74,Shannon-Wiener指数为2.091~2.611,Pielou指数为0.904~0.917,Simpson指数为0.859~0.918,Jaccard指数为0.417、0.233、0.191。结论不同生境中粉螨的孳生密度、多样性及相似性差异较大,温湿度差异、粉螨食性习性及人为干扰均为重要影响因素。  相似文献   
69.
70.

Background

Sublingual immunotherapy (SLIT) can improve the symptoms of allergic rhinitis and modify its natural history; however, its efficacy varies among patients. This study aimed to determine which factors modify the effect of SLIT through post hoc analysis of a previous phase 3 trial of standardized Japanese cedar (JC) pollen extract (CEDARTOLEN®).

Methods

The study included 482 patients who had previously completed a phase 3 trial during two seasons. The SLIT and placebo groups each contained 241 subjects. Because pollen dispersal differed in the two seasons, we identified good and poor responders from the SLIT group in the 2nd season. We compared patient baseline characteristics, changes in serum immunoglobulin, and severity of symptoms in the 1st season between good and poor responders, as well as between SLIT and placebo groups.

Results

When we compared the baseline characteristics of good and poor responders, a significant difference was observed in body mass index (BMI) such that the patients with BMI ≥25 presented with lower treatment efficacy. No significant difference was observed in correlation with any other factors or treatment-induced alterations of serum immunoglobulin levels. We found that 75.3% of the patients with moderate symptoms and 50.9% of the patients with severe or very severe symptoms in the 1st season met our criteria for good responders in the 2nd season.

Conclusions

BMI might modify the effect of SLIT; however, other factors were not related clearly. The severity of symptoms in the 1st season of treatment does not predict that in the 2nd season.  相似文献   
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