University of Texas Medical Branch

About: University of Texas Medical Branch is a education organization based out in Galveston, Texas, United States. It is known for research contribution in the topics: Population & Virus. The organization has 22033 authors who have published 38268 publications receiving 1517502 citations. The organization is also known as: The University of Texas Medical Branch at Galveston & UTMB.

Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise

Abstract: The present study was designed to determine whether consumption of an oral essential amino acid-carbohydrate supplement (EAC) before exercise results in a greater anabolic response than supplementa...

Muscarinic receptors: their distribution and function in body systems, and the implications for treating overactive bladder

Abstract: 1 The effectiveness of antimuscarinic agents in the treatment of the overactive bladder (OAB) syndrome is thought to arise through blockade of bladder muscarinic receptors located on detrusor smooth muscle cells, as well as on nondetrusor structures. 2 Muscarinic M-3 receptors are primarily responsible for detrusor contraction. Limited evidence exists to suggest that M-2 receptors may have a role in mediating indirect contractions and/or inhibition of detrusor relaxation. In addition, there is evidence that muscarinic receptors located in the urothelium/suburothelium and on afferent nerves may contribute to the pathophysiology of OAB. Blockade of these receptors may also contribute to the clinical efficacy of antimuscarinic agents. 3 Although the role of muscarinic receptors in the bladder, other than M3 receptors, remains unclear, their role in other body systems is becoming increasingly well established, with emerging evidence supporting a wide range of diverse functions. Blockade of these functions by muscarinic receptor antagonists can lead to similarly diverse adverse effects associated with antimuscarinic treatment, with the range of effects observed varying according to the different receptor subtypes affected. 4 This review explores the evolving understanding of muscarinic receptor functions throughout the body, with particular focus on the bladder, gastrointestinal tract, eye, heart, brain and salivary glands, and the implications for drugs used to treat OAB. The key factors that might determine the ideal antimuscarinic drug for treatment of OAB are also discussed. Further research is needed to show whether the M-3 selective receptor antagonists have any advantage over less selective drugs, in leading to fewer adverse events. (Less)

Uncoupling of cardiac muscarinic and beta-adrenergic receptors from ion channels by a guanine nucleotide analogue.

Abstract: Guanine nucleotide binding proteins, interchangeably called N or G proteins, seem to be the primary signal-transducing components of various agonist-induced cell membrane functions. In the heart, G proteins have been implicated in beta-adrenergic modulation of the slow inward Ca2+ current. We have investigated the role of G proteins in muscarinic activation of an inwardly rectifying, acetylcholine (ACh)-induced K+ current (IACh), and beta-adrenergic activation of an (isoprenaline)-induced Ca2+ current (Isi). Here we report that intracellular application of the non-hydrolysable GTP analogue 5'-guanylylimidodiphosphate (GppNHp) brought about an agonist-induced, antagonist-resistant, persistent activation of IACh and Isi. This functional uncoupling of channel from receptor suggests that the muscarinic receptor and the IACh channel are separate molecular structures. Membrane conductance responses to sequential activation of muscarinic and beta-adrenergic receptors demonstrate that in contrast to the muscarinic inhibition of Isi, muscarinic stimulation of IACh is mediated by a G protein via a pathway that does not involve adenylate cyclase. Taken together, the results support the notion that agonist is required to induce GppNHp binding and/or activation of the G proteins. Once triggered by agonist, the control system remains maximally activated, thereby transforming the cell so that it no longer responds to subsequent homologous receptor-mediated signals.

Human granulocytic ehrlichiosis in the upper Midwest United States. A new species emerging

Abstract: Objective. —To characterize the clinical presentation and course, laboratory findings, and treatment outcome of 12 patients with human granulocytic ehrlichiosis. Setting. —The 12 patients were male, ranged in age from 29 to 91 years, and contracted their illness in Wisconsin or Minnesota. Methods. —Cases were recognized by the presence of intracytoplasmic inclusions (morulae) in peripheral neutrophils of patients presenting with temperature of 38.5°C or higher, chills, severe headache, and myalgias. All patients had a complete blood cell count and blood chemistry profile. Blood smears were examined by light microscopy. All available paired serum samples were analyzed for presence of indirect fluorescent antibodies againstEhrlichia chaffeensis, Ehrlichia phagocytophila, andEhrlichia equi. Blood samples from 12 patients were subjected to polymerase chain reaction analysis using primers specific for theE phagocytophila/E equigroup, primers that include the agent identified in our patients, as well asE chaffeensis. Results. —Varying combinations of leukopenia, anemia, and thrombocytopenia were found in all but one patient. All 12 patients demonstrated morulae in the cytoplasm of neutrophils, but not in mononuclear white blood cells. Serum assays failed to detect antibodies againstE chaffeensis, but eight of 10 patients and seven of 10 patients tested had antibody titers of 1:80 or more forE phagocytophilaandE equi, respectively. Polymerase chain reaction products obtained with primers forE phagocytophila, E equi, and the granulocytotropicEhrlichiarevealed that seven patients were infected with the same agent. The results of serological assays or polymerase chain reaction strongly suggest that all 12 patients were infected byE phagocytophila, E equi, or a closely relatedEhrlichiaspecies. Two of the 12 patients died. The other 10 patients improved rapidly with oral doxycycline treatment. Conclusions. —We believe that all 12 patients have been infected with a granulocyticEhrlichiaspecies, reflecting a recently described new disease entity. The infective organism appears to be closely related toE phagocytophilaandE equi. The geographic domain of human granulocytic ehrlichiosis is currently unknown. This novel granulocyticEhrlichiaspecies is capable of causing fatal infections in humans. Early detection and treatment with tetracycline drugs appear to offer the best chance for complete recovery. (JAMA. 1994;272:212-218)