PubMed Health⌕ Search

Biomedical subjects

G Rust

Publications and source records attributed to G Rust.

11 recordsLinked to original sources

The Morehouse Faculty Development Program: methods and 3-year outcomes.

BACKGROUND AND OBJECTIVES: Faculty development is an established method for increasing the number and effectiveness of faculty in family medicine. However, few published studies focus specifically on the use of faculty development to increase minority representation among faculty. Underrepresented minorities comprise 20% of the nation's population but only 3% of medical school faculty. In the entire nation, only 52 full-time teachers of family medicine are African-Americans. Morehouse School of Medicine has developed an effective model for training large numbers of underrepresented minority physicians to become academic family physicians. From 1993-1996, we trained 23 community-based physicians, three new faculty, six existing faculty, and three full-time fellows as teachers of family medicine. Of 35 participants, 33 were underrepresented minorities. Cultural issues in teaching and communication are an integral part of the curriculum. Seventy-three percent of graduates now teach medical students or residents either full-time or part-time. Further studies are needed to test the replicability of this model in non-minority institutions, as well as to achieve greater cost-effectiveness and improve academic outcomes such as publications and research. Significant faculty diversity is necessary and achievable, if institutions are willing to commit significant resources and network with minority health professionals and institutions.

Black or African American↗

Beta-subunits co-determine the sensitivity of rat neuronal nicotinic receptors to antagonists.

We have investigated the effect of 4 ganglionic cholinergic antagonists (hexamethonium, mecamylamine, pentolinium, trimetaphan) on rat alpha 3 beta 2 and alpha 3 beta 4 neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes. Current responses were elicited by fast application of acetylcholine on voltage-clamped oocytes (holding potentialVh = -80mV). Concentration-inhibition curves were used to get estimates of IC50, the antagonist concentration yielding 50% reduction of the peak current. The KB's of the antagonists were calculated using estimates of the apparent KD of acetylcholine. The order of affinity of the antagonists was similar for both receptor subtypes: mecamylamine approximately pentolinium > hexamethonium > trimetaphan. However, alpha 3 beta 4 neuronal nAChRs were 9 to 22 times more sensitive to each of the 4 antagonists than alpha 3 beta 2 receptors. These results further underline the importance of the beta-subunit as co-determinant of the functional properties of neuronal nAChRs.

Animals↗

Expression of neuronal nicotinic acetylcholine receptor subunit genes in the rat autonomic nervous system.

In the autonomic nervous system efferent signals are relayed in sympathetic and parasympathetic ganglia. Fast synaptic transmission between pre- and postsynaptic neurons is achieved by neuronal nicotinic acetylcholine receptors (nAChRs). There is still little known about the subunit composition of these receptors. Establishing the subunit composition of native neuronal nAChRs is important for the understanding of their functional properties both in vivo and after expression in heterologous expression systems. We have combined in situ hybridization and autoradiography to detect the presence of mRNAs encoding subunits of neuronal nAChRs in sympathetic and parasympathetic ganglia. Inspection of the autoradiographs showed that the hybridization signal of five riboprobes (alpha 3, alpha 4-1, alpha 7, beta 2 and beta 4) was significantly higher than the unspecific signal obtained with sense riboprobes. The distribution of alpha 7 was tissue-dependent: alpha 7 riboprobe binding was detected in the neurons of the superior cervical ganglion, adrenal medulla and ciliary ganglion. In contrast, the alpha 7 hybridization signal was found only in a small fraction (1-3%) of the neurons of the sphenopalatine and otic ganglia. Our results are consistent with the idea that alpha 3 mRNA expression levels are somewhat higher than those of alpha 7, alpha 4-1, beta 2 and beta 4.

Animals↗

Unusual pharmacology of (+)-tubocurarine with rat neuronal nicotinic acetylcholine receptors containing beta 4 subunits.

We have investigated the functional properties of four rat neuronal nicotinic acetylcholine receptor types expressed in Xenopus oocytes after injection of pairwise combinations of mRNA encoding alpha 2 or alpha 3 receptor subunits with mRNA encoding beta 2 or beta 4 receptor subunits. Current responses evoked by rapid application of cholinergic agonists (acetylcholine, nicotine, or 1,1-dimethyl-4-phenylpiperazinium) were recorded from voltage-clamped oocytes. Substituting BaCl2 for CaCl2 in the external solution increased the apparent Kd values of beta 4 subunit-containing receptors for acetylcholine but decreased the apparent Kd values of beta 2 subunit-containing receptors. Inhibition curves for the cholinergic antagonist (+)-tubocurarine were measured in BaCl2 medium at low agonist concentrations. (+)-Tubocurarine was a competitive antagonist of acetylcholine at neuronal nicotinic acetylcholine receptors that coexpressed the beta 2 subunit; the estimated Kb values were 3.6 microM (alpha 2 beta 2 receptors) and 390 nM (alpha 3 beta 2 receptors). In contrast, (+)-tubocurarine enhanced the peak responses evoked by low acetylcholine concentrations at alpha 2 beta 4 and alpha 3 beta 4 neuronal nicotinic acetylcholine receptors, without being a partial agonist. The maximal increase was observed at 5 microM and 10 microM (+)-tubocurarine for alpha 2 beta 4 and alpha 3 beta 4 receptors, respectively. Higher (+)-tubocurarine concentrations inhibited cholinergic responses, thus yielding a "bell-shaped" concentration-response curve.

Animals↗

Sinus histiocytosis with massive lymphadenopathy: remission with chemotherapy.

A case of sinus histiocytosis with massive lymphadenopathy (SHML) is reported, in which the patient had severe life-threatening complications resulting from SHML. The disease process was extensive involving the respiratory tract, skeleton, integument, orbit and eyelid, uveal tract, and the lymphatic system. Treatment with cytotoxic agents (chlorambucil, prednisone) resulted in resolution of the airway obstruction and was effective in managing these severe complications with minimal observed toxicity.

Biopsy↗

What's what: E & GW.

Explore the source record for details and available documents.

Collective Bargaining↗

[Vaginal cytological studies on the new delayed-action estrogen-ethinylestradiol sulfonate].

The colpocytologic efficacy of a new estrogen - ethinylestradiolsulfonate - has been studied in postmenopausal and fertile women. According to the depot character of the compound, ranging between ethinylestradiol and quinestrol, it exhibits a high and prolonged proliferative effect on the atropich vaginal epithelia. The weekly application of 1 mg of the substance in a contraceptive regimen causes a high grade of maturation with considerable individual differences. A single dose of 1 mg ethinylestradiolsulfonate quickly influences conditions of estrogen difficiency in the vaginal epithelia.

Contraceptives, Oral↗