Medical University of South Carolina

About: Medical University of South Carolina is a education organization based out in Charleston, South Carolina, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 23436 authors who have published 45440 publications receiving 1769397 citations. The organization is also known as: MUSC & Medical College of the State of South Carolina.

Neural substrates of conditioned-cued relapse to drug-seeking behavior.

Abstract: Relapse to drug use following abstinence is a significant impediment in the long-term treatment of drug abuse and dependence. Conditioned stimuli are believed to be critically involved in activating drug craving and relapse to compulsive drug-taking behavior. Studies in humans and animal models have recently begun to identify the fundamental neural circuitry that mediates relapse following withdrawal from chronic drug self-administration. The current review summarizes key findings in this area that have converged on the amygdalar complex and regions of the frontal lobe as critical structures in conditioned-cued relapse. It is proposed that the amygdala is a key regulator of discrete stimulus-reinforcer associations, while the anterior cingulate and orbitofrontal cortex are critical regulators of relapse evoked by conditioned stimuli that predict drug availability. This corticolimbic circuitry may form the neural basis of multiple long-term conditioned associations produced by a variety of drugs of abuse ranging from psychostimulants to opiates. Future studies aimed at discerning the functional roles of these pathways will provide critical direction for the development of treatments for the prevention of relapse.

Repeated Episodes of Ethanol Withdrawal Potentiate the Severity of Subsequent Withdrawal Seizures: An Animal Model of Alcohol Withdrawal “Kindling”

Abstract: Prior experience with ethanol (EtOH) withdrawal may sensitize an individual to subsequent withdrawal episodes. It has been hypothesized that the progressive intensification of the EtOH withdrawal syndrome following repeated episodes of EtOH intoxication and withdrawal may represent the manifestations of a "kindling" mechanism. The purpose of this study was to develop an animal model of EtOH withdrawal that is sensitive to the effects of prior withdrawal experience. Adult male C3H mice were chronically exposed to EtOH vapor in inhalation chambers prior to withdrawal testing. A multiple withdrawal (MW) group received 3 cycles of 16 hr EtOH vapor separated by 8-hr periods of abstinence; a single withdrawal (SW) group received a single bout of EtOH exposure (16 hr); a third group (SW-CONT) experienced a single withdrawal episode after receiving the equivalent amount of EtOH intoxication as the MW group (16 x 3 = 48 hr), but in a continuous (uninterrupted) fashion; and a fourth group (C) served as controls, not receiving any EtOH exposure throughout the study. Severity of the withdrawal response was assessed by scoring handling-induced convulsions hourly for the first 10 hr and then at 24 hr postwithdrawal. The results indicated that the severity of EtOH withdrawal seizures was significantly greater in animals that had a prior history of withdrawal episodes (MW group) in comparison to a separate group of animals that were tested following a single withdrawal from the same 16-hr intoxication period (SW group).(ABSTRACT TRUNCATED AT 250 WORDS)

Mortality Rates and Risk Factors for Coronary Disease in Black as Compared with White Men and Women

Abstract: Background Currently recognized risk factors for coronary artery disease have been identified primarily from investigations of white populations. In this investigation, we estimated mortality rates for coronary disease and for any cause and identified risk factors for death from coronary disease among whites and blacks. Methods Data collected over a 30-year period in the Charleston Heart Study were used to estimate mortality rates and quantify associations with risk factors assessed at the base-line examination in 1960 and 1961 of 653 white men, 333 black men, 741 white women, and 454 black women. Results There were no significant racial differences in the rate ratios for death from coronary disease; however, women had significantly lower death rates than men. Over the 30-year period, the mortality rates for coronary disease per 1000 person-years were 5.2 for white men (95 percent confidence interval, 4.1 to 6.3), 4.6 for black men (3.0 to 6.2), 2.1 for white women (1.6 to 2.6), and 3.2 for black women (2...

Vitamin D deficiency and seasonal variation in an adult south Florida population

Abstract: Hypovitaminosis D is associated with impaired neuromuscular function, bone loss, and fractures. If a person is not taking a vitamin supplement, sun exposure is often the greatest source of vitamin D. Thus, vitamin D deficiency is not uncommon in the winter, particularly in northern latitudes. Our goal was to establish the prevalence of vitamin D deficiency in south Florida (U.S.), a region of year-round sunny weather. At the end of the winter, 212 men and women attending an internal medicine clinic at a local county hospital were enrolled for measurements of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D, and PTH; 99 participants returned at the end of summer. The mean (+/-sd) winter 25(OH)D concentration was 24.9 +/- 8.7 ng/ml (62.3 +/- 21.8 nmol/liter) in men and 22.4 +/- 8.2 ng/ml (56.0 +/- 20.5 nmol/liter) in women. In winter, the prevalence of hypovitaminosis D, defined as 25(OH)D less than 20 ng/ml (50 nmol/liter), was 38% and 40% in men and women, respectively. In the 99 subjects who returned for the end of summer visit, the mean 25(OH)D concentration was 31.0 +/- 11.0 ng/ml (77.5 +/- 27.5 nmol/liter) in men and 25.0 +/- 9.4 ng/ml (62.5 +/- 23.5 nmol/liter) in women. Seasonal variation represented a 14% summer increase in 25(OH)D concentrations in men and a 13% increase in women, both of which were statistically significant. The prevalence of hypovitaminosis D is considerable even in southern latitudes and should be taken into account in the evaluation of postmenopausal and male osteoporosis.

5-Aminoimidazole-4-Carboxamide-1-β-4-Ribofuranoside Inhibits Proinflammatory Response in Glial Cells: A Possible Role of AMP-Activated Protein Kinase

Abstract: AMP-activated protein kinase (AMPK) is tightly regulated by the cellular AMP:ATP ratio and plays a central role in the regulation of energy homeostasis and metabolic stress. A pharmacological activator of AMPK, 5-amino-4-imidazole carboxamide riboside (AICAR) inhibited lipopolysaccharide (LPS)-induced expression of proinflammatory cytokines (tumor necrosis factor alpha, interleukin-1beta, and interleukin-6) and inducible nitric oxide synthase in primary rat astrocytes, microglia, and peritoneal macrophages. AICAR attenuates the LPS-induced activation of nuclear factor kappaB via downregulation of IkappaB kinase alpha/beta activity. It also inhibits nuclear translocation of CCAAT/enhancer-binding protein (C/EBP) transcription factor by inhibiting the expression of C/EBP-delta in brain glial cells. The dominant negative form of AMPKalpha2 (D157A) and its antisense documents a possible role of AMPK in the regulation of the cellular proinflammatory process. AICAR also inhibited the production of inflammatory mediators in serum and their expression in CNS of rats injected with a sublethal dose of LPS by intraperitoneal injection. These observations in cultured cells as well as in the animal model suggest that AICAR may be of therapeutic value in treating inflammatory diseases.