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Background

The most common abnormal spirometric pattern reported in WTC worker and volunteer cohorts has consistently been that of a nonobstructive reduced forced vital capacity (low FVC). Low FVC is associated with obesity, which is highly prevalent in these cohorts. We used quantitative CT (QCT) to investigate proximal and distal airway inflammation and emphysema in participants with stable low FVC pattern.

Methods

We selected study participants with at least two available longitudinal surveillance spirometries, and a chest CT with QCT measurements of proximal airway inflammation (wall area percent, WAP), end-expiratory air trapping, suggestive of distal airway obstruction (expiratory to inspiratory mean lung attenuation ratio, MLAEI), and emphysema (percentage of lung volume with attenuation below − 950 HU, LAV%). The comparison groups in multinomial logistic regression models were participants with consistently normal spirometries, and participants with stable fixed obstruction (COPD).

Results

Compared to normal spirometry participants, and after adjusting for age, sex, race/ethnicity, BMI, smoking, and early arrival at the WTC disaster site, low FVC participants had higher WAP (ORadj 1.24, 95% CI 1.06, 1.45, per 5% unit), suggestive of proximal airway inflammation, but did not differ in MLAEI, or LAV%. COPD participants did not differ in WAP with the low FVC ones and were more likely to have higher MLAEI or LAV% than the other two subgroups.

Discussion

WTC workers with spirometric low FVC have higher QCT-measured WAP compared to those with normal spirometries, but did not differ in distal airway and emphysema measurements, independently of obesity, smoking, and other covariates.

  相似文献   
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Objective

To identify the degree of selection into consumer-directed health plans (CDHPs) versus traditional plans over time, and factors that influence choice and temper risk selection.

Data Sources/Study Setting

Sixteen large employers offering both CDHP and traditional plans during the 2004–2007 period, more than 200,000 families.

Study Design

We model CDHP choice with logistic regression; predictors include risk scores, in addition to family, choice setting, and plan characteristics. Additional models stratify by account type or single enrollee versus family.

Data Collection/Extraction Methods

Risk scores, family characteristics, and enrollment decisions are derived from medical claims and enrollment files. Interviews with human resources executives provide additional data.

Principal Findings

CDHP risk scores were 74 percent of traditional plan scores in the first year, and this difference declined over time. Employer contributions to accounts and employee premium savings fostered CDHP enrollment and reduced risk selection. Having to make an active choice of plan increased CDHP enrollment but also increased risk selection. Risk selection was greater for singles than families and did not differ between HRA and HSA-based CDHPs.

Conclusions

Risk selection was not severe and it was well managed. Employers have effective methods to encourage CDHP enrollment and temper selection against traditional plans.  相似文献   
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Cells of the osteoblast lineage play an important role in regulating the hematopoietic stem cell (HSC) niche and early B‐cell development in animal models, perhaps via parathyroid hormone (PTH)‐dependent mechanisms. There are few human clinical studies investigating this phenomenon. We studied the impact of long‐term daily teriparatide (PTH 1‐34) treatment on cells of the hematopoietic lineage in postmenopausal women. Twenty‐three postmenopausal women at high risk of fracture received teriparatide 20 mcg sc daily for 24 months as part of a prospective longitudinal trial. Whole blood measurements were obtained at baseline, 3, 6, 12, and 18 months. Flow cytometry was performed to identify hematopoietic subpopulations, including HSCs (CD34+/CD45(moderate); ISHAGE protocol) and early transitional B cells (CD19+, CD27‐, IgD+, CD24[hi], CD38[hi]). Serial measurements of spine and hip bone mineral density (BMD) as well as serum P1NP, osteocalcin, and CTX were also performed. The average age of study subjects was 64 ± 5 years. We found that teriparatide treatment led to an early increase in circulating HSC number of 40% ± 14% (p = 0.004) by month 3, which persisted to month 18 before returning to near baseline by 24 months. There were no significant changes in transitional B cells or total B cells over the course of the study period. In addition, there were no differences in complete blood count profiles as quantified by standard automated flow cytometry. Interestingly, the peak increase in HSC number was inversely associated with increases in bone markers and spine BMD. Daily teriparatide treatment for osteoporosis increases circulating HSCs by 3 to 6 months in postmenopausal women. This may represent a proliferation of marrow HSCs or increased peripheral HSC mobilization. This clinical study establishes the importance of PTH in the regulation of the HSC niche within humans. © 2014 American Society for Bone and Mineral Research.  相似文献   
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Information obtained on the Internet regarding medical procedures is largely unregulated and can be confusing. The aims of this study were to assess use of the Internet by patients attending hospital for oral and maxillofacial procedures, and to assess the quality of information provided at consultation. Data were collected prospectively using a confidential questionnaire, which was distributed to consecutive patients attending for elective operations at 2 oral and maxillofacial units: Crosshouse Hospital, Kilmarnock, and Queen Alexandra Hospital, Portsmouth (n = 100 at each unit). All the distributed questionnaires were returned. At both units, 95% of patients thought that discussion at the initial consultation was good or very good, and 84% at both units stated that they had access to the Internet. Internet access was consistently high among all age groups up to the age of 65, but in those aged over 65 it was considerably lower. A total of 22/84 patients (26%) at Crosshouse, and 14/84 (17%) at Queen Alexandra used the Internet to gain further information regarding their condition or procedure. All of those (n = 14) at Queen Alexandra, and 21/22 at Crosshouse had used Google to search for the information. Those who used the Internet to find information on their medical condition or procedure found it to be a useful resource, but they also stated that the information caused some concerns. With use of the Internet and access to it increasing we highlight the need for regulated and appropriate websites to which patients should be directed.  相似文献   
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BackgroundWith ever-increasing demand for total knee arthroplasty (TKA), most healthcare systems around the world are concerned about its socioeconomic burden. Most centers have universally adopted well-defined clinical care pathways to minimize adverse outcomes, maximize volume, and limit costs. However, there are no prospective comparative trials reporting benefits of these risk mitigation (RM) strategies.MethodsThis is a prospective cohort study comparing post-TKA 90-day complications between patients undergoing RM before surgery and those following a standard protocol (SP). In the RM group, we used a 20-point checklist to screen for modifiable risk factors and evaluate the need for optimizing non-modifiable comorbidities. Only when optimization goals were achieved, patients were offered TKA.ResultsTKA was performed in 811 patients in the SP group and in 829 in the RM group, 40% of which were simultaneous bilateral TKA. In both groups, hypertension was the most prevalent comorbidity (48%), followed by diabetes (20%). A total of 43 (5.3%) procedure-related complications were seen over the 90-day postoperative period in the SP group, which was significantly greater than 26 (3.1%) seen in the RM group (p = 0.039). The commonest complication was pulmonary thromboembolic, 6 in each group. Blood transfusion rate was higher in the SP group (6%) than in the RM group (< 1%).ConclusionsScreening and RM can reduce 90-day complications in patients undergoing TKA.  相似文献   
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