Emergency department usage patterns among residents of Hardin, Jefferson, and Orange Counties in southeast Texas

Emergency departments (EDs) have been called the net below the safety net due to their long history of providing care to the uninsured and others lacking access to the healthcare system. In past years, those with Medicaid and, more recently, those with Medicare, are also utilizing the ED as a medical home for routine primary care. There are many reasons for this but the costs to the community have become increasingly burdensome. ^ To evaluate how often the ED is being utilized for primary care, we applied a standardized tool, the New York University Algorithm, to over 43,000 ED visits when no hospitalization was required made by Hardin, Jefferson, and Orange County residents over a 12 month period. We compared our results to Harris County, where studies using the same framework have been performed, and found that sizeable segments of the population in both areas are utilizing the ED for non-emergent primary care that could be treated in a more cost-effective community setting. ^ We also analyzed our dataset for visit-specific characteristics. We found evidence of two possible health care disparities: (1) Blacks had a higher rate of primary care-related ED visits in relation to their percentage of the population when compared to other racial/ethnic groups; and (2) when form of payment is considered, the uninsured were more likely to have a primary care-related ED visit than any other group. These findings suggest a lack of community-based primary care services for the medically needy in Southeast Texas. ^ We believe that studies such as this are warranted elsewhere in Texas as well. We plan to present our findings to local policy makers, who should find this information helpful in identifying gaps in the safety net and assist them in better allocating scarce community resources. ^

Simulation of Drosophila circadian oscillations, mutations, and light responses by a model with VRI, PDP-1, and CLK.

A model of Drosophila circadian rhythm generation was developed to represent feedback loops based on transcriptional regulation of per, Clk (dclock), Pdp-1, and vri (vrille). The model postulates that histone acetylation kinetics make transcriptional activation a nonlinear function of [CLK]. Such a nonlinearity is essential to simulate robust circadian oscillations of transcription in our model and in previous models. Simulations suggest that two positive feedback loops involving Clk are not essential for oscillations, because oscillations of [PER] were preserved when Clk, vri, or Pdp-1 expression was fixed. However, eliminating positive feedback by fixing vri expression altered the oscillation period. Eliminating the negative feedback loop in which PER represses per expression abolished oscillations. Simulations of per or Clk null mutations, of per overexpression, and of vri, Clk, or Pdp-1 heterozygous null mutations altered model behavior in ways similar to experimental data. The model simulated a photic phase-response curve resembling experimental curves, and oscillations entrained to simulated light-dark cycles. Temperature compensation of oscillation period could be simulated if temperature elevation slowed PER nuclear entry or PER phosphorylation. The model makes experimental predictions, some of which could be tested in transgenic Drosophila.