Publications

Six and one-half million Californians were uninsured for all or some of 2005, a number that is as large as the combined populations of nine other states. The number of uninsured represented one in five children and nonelderly adults, a rate that was slightly lower than in 2003 due to California's tight labor markets and expanding enrollment and retention in California's public coverage programs for children. These marginal improvements are unlikely to continue unabated given the instability of employment-based insurance coverage in the face of rising costs. In this policy brief, we compare insurance coverage over time using the California Health Interview Surveys conducted in 2001, 2003 and 2005. We look at the type of coverage over the past 12 months for both children and nonelederly adults.

Corneal epithelial stem cells are known to be localized to the basal layer of the limbal epithelium, providing a model system for epithelial stem cell biology; however, the mechanisms regarding the maintenance of these stem cells in their specialized niche remain poorly understood. N-cadherin is a member of the classic cadherin family and has previously been demonstrated to be expressed by hematopoietic stem cells. In the present study, we demonstrate that N-cadherin is expressed by putative stem/progenitor cells, as well as melanocytes, in the human limbal epithelial stem cell niche. In addition, we demonstrate that upon in vitro culture using 3T3 feeder layers, loss of N-cadherin expression occurs with cell proliferation. These results indicate that N-cadherin may be a critical cell-to-cell adhesion molecule between corneal epithelial stem/progenitor cells and their corresponding niche cells in the limbal epithelium.

BACKGROUND

Sphingosine kinase (SKase) has been implicated in the protection of hearts from ischemia/reperfusion injury. This hypothesis was further examined.

MATERIAL/METHODS

Changes in SKase activity and cardiac function (left ventricular developed pressure, LVDP, and infarct size) in response to ischemia and reperfusion were studied in adult rat hearts by the ex vivo Langendorff method. Following initial equilibration or preconditioning, there was 45 min no-flow ischemia and then 45 min of reperfusion.

RESULTS

SKase activity declined 61% during ischemia and did not recover upon reperfusion. LVDP also did not recover upon reperfusion and the infarct size was 47%. A short 30 min period of ischemia was associated with variable recovery of SKase activity that directly correlated with LVDP recovery. Preconditioning of hearts reduced the decrease in SKase activity during ischemia by half, and upon reperfusion activity returned to normal. The LVDP recovered 79% and infarct size was small. Preconditioned hearts had higher S-1-P levels after ischemia/reperfusion relative to non-preconditioned hearts. The decline in SKase activity during ischemia of preconditioned hearts could not be mimicked in vitro by treatment with protein phosphatases. Attempts to alter activity of SKase from control, preconditioned, ischemic, or reperfused hearts by phosphorylation with ERK1/2 were unsuccessful. Treatment of non-preconditioned hearts at reperfusion with 100 nM S-1-P improved recovery of LVDP. The SKase inhibitor dimethylsphingosine blocked hemodynamic recovery in preconditioned hearts.

CONCLUSIONS

The data support a role for SKase activity in recovery of hemodynamic function after ischemic injury and also in the cardioprotective effect of preconditioning.

BACKGROUND

Caecal intubation is a necessary step in the complete endoscopic evaluation of the colon. Studies have estimated that experienced colonoscopists may fail to reach the caecum in up to 10% of cases.

AIMS

To evaluate the utility of the double balloon enteroscope used for complete examination of the colon in patients with incomplete standard colonoscopy.

PATIENTS

Twenty consecutive patients with incomplete colonoscopies within the Veterans Affairs Palo Alto Health Care System. Mean age of 66 years (S.D.+/-12 years, range 46-84), 16 men.

METHODS

Prospective single-centre case series on the caecal intubation rate using standard double balloon enteroscope technique in patients with previous incomplete conventional colonoscopy.

RESULTS

Use of the standard double balloon enteroscope technique permitted complete colonoscopy to be achieved in 95% of the patients (19/20). Seven patients (35%) had significant pathology beyond the extent of the prior incomplete colonoscopy. We performed endoscopic mucosal resection, polypectomy or biopsy. The mean time to reach the caecum was 28 min (S.D.+/-20 min, range 6-90 min). The sedation was similar to conventional colonoscopy. No complications occurred.

CONCLUSIONS

The double balloon enteroscope technology and technique can be used to complete examination of the colon in patients who were referred because of incomplete standard colonoscopy.