Publications

The contraction of hepatic stellate cells has been proposed to mediate fibrosis by regulating sinusoidal blood flow and extracellular matrix remodeling. Abundant data from diverse, yet complementary, experimental methods support a robust model for the regulation of contractile force generation by stellate cells. In this model, soluble factors associated with liver injury, including endothelin 1 and nitric oxide, are transduced primarily through Rho signaling pathways that promote the myosin II-powered generation of contractile force by stellate cells. The enhanced knowledge of the role and differential regulation of stellate cell contraction may facilitate the discovery of new and targeted strategies for the prevention and treatment of hepatic fibrosis.

INTRODUCTION

To determine the relationship between housing instability, economic standing, and access to health care and use of acute care services.

METHODS

We performed a meta-regression using four nationally representative surveys. The independent variable was an ordered measure of economic and housing instability: 1) the general population, 2) low-income population, 3) never homeless users-of-subsistence-services, 4) unstably housed, 5) formerly homeless, and 6) the actively homeless. Dependent variables were four measures of health care access and three measures of acute health care utilization.

RESULTS

Worsening housing instability and economic standing was associated with poorer access: being uninsured (5.4% per unit increase, 95% CI 1.7-9.2%, p=.011), postponing needed care (3.3%, 95% CI 1.9-4.7%, p=.001), postponing medications (6.1%, 95% CI 1.5-10.6%, p=.035), and with one measure of acute health care utilization: higher hospitalization rates (2.9%, 95% CI 1.2-4.6%, p=.008).

DISCUSSION

Economic and housing instability should be considered a graded risk factor for poor access to health care.

BACKGROUND

Remote magnetic catheter navigation (RCN) is gaining acceptance in clinical cardiac electrophysiology, but details regarding how RCN affects procedure execution are not well characterized.

METHODS

From January 1, 2005, to November 30, 2007, 721 cases were retrospectively analyzed and compared. Of these, 127 used RCN and 594 used manual catheter navigation (MCN). Data including procedure time, fluoroscopy time, ablation catheter, procedural success, and complications were extracted from our procedure database and compared between RCN and MCN.

RESULTS

RCN use significantly decreased fluoroscopy time for atrial fibrillation (AF) ablation (-29 minutes, P < 0.001), atrioventricular nodal reentrant tachycardia ablation (-14 minutes, P < 0.001), and atrioventricular reentrant tachycardia ablation (-18 minutes, P = 0.045). While RCN significantly increased mean procedure time for AF (+36 minutes, P = 0.003) and atypical atrial flutter cases (+116 minutes, P = 0.016), RCN AF procedure time diminished with increasing number of cases performed. Two cases of tamponade occurred during AF ablation using MCN (2.2%, 2 of 91 cases). No tamponade occurred during all 75 AF ablations with RCN.

CONCLUSION

RCN can reduce fluoroscopy time and may reduce complications during catheter ablation. While it may increase total procedure duration, procedure times decrease with increasing operator experience. (PACE 2008; 31:1399-1404).

OBJECTIVE

This experiment was designed to test if controlled exposure to particles and ozone would result in decreased heart rate variability (HRV).

METHODS

Five asthmatic adults were exposed for 4 hours to; filtered-air, carbon and ammonium nitrate particles, and particles and ozone. Twenty-minute electrocardiograms were obtained before and after each exposure.

RESULTS

Standard deviation of all normal-to-normal beat intervals (SDNN) decreased significantly across particles and ozone exposure compared with across filtered-air exposure (P = 0.01). Changes in SDNN-I (P = 0.04) and normalized low and high frequency (P = 0.02) were also seen across particles and ozone exposure; although these changes may best be characterized as trends given the small sample size. No significant changes in HRV were seen across the filtered-air or particles-only exposures.

CONCLUSIONS

The results of this study suggest that combined particle and ozone exposure may decrease HRV in asthmatics. Further investigation is needed to confirm this finding.

OBJECTIVE

To determine sex, breed, and age distributions in a population of horses with cervical vertebral compressive myelopathy (CVCM), compared with contemporaneous control horses.

DESIGN

Retrospective case-control study.

ANIMALS

811 horses with CVCM and 805 control horses.

PROCEDURES

The Veterinary Medical Database was searched to identify horses with CVCM and contemporaneous control horses registered between July 1974 and August 2007. Admission date, admitting institution, sex, breed, age at the time of registration in the database, weight, and discharge status (alive, died, or euthanized) were recorded for each case and control horse.

RESULTS

On the basis of results of multivariable logistic regression analysis, geldings and sexually intact males had a significantly higher likelihood of having CVCM than females (odds ratio [OR], 2.0 [95% confidence interval, 1.5 to 2.6]; and OR, 2.4 [95% confidence interval, 1.8 to 3.2], respectively). Thoroughbreds, Tennessee Walking Horses, and Warm-bloods were overrepresented in the CVCM group, compared with Quarter Horses. Horses that ranged from < 6 months to < 7 years of age had significantly higher odds of having CVCM, compared with horses > or = 10 years of age.

CONCLUSIONS AND CLINICAL RELEVANCE

Sex, breed, and age predilections were detected in horses with CVCM. Improved understanding of these factors will aid clinical recognition of the disease in groups that may have a high prevalence of CVCM or were previously not recognized to be commonly affected. The results may also stimulate future investigations to further delineate etiopathogenesis, such as breed-related genetic causality.