Identification of insulin receptor substrate proteins as key molecules for the TbetaR-V/LRP-1-mediated growth inhibitory signaling cascade in epithelial and myeloid cells.

The type V TGF-beta receptor (TbetaR-V) mediates IGF-independent growth inhibition by IGFBP-3 and mediates growth inhibition by TGF-beta1 in concert with the other TGF-beta receptor types. TbetaR-V was recently found to be identical to LRP-1. Here we find that insulin and (Q3A4Y15L16) IGF-I (an IGF-I analog that has a low affinity for IGFBP-3) antagonize growth inhibition by IGFBP-3 in mink lung epithelial cells (Mv1Lu cells) stimulated by serum.

Brain-derived neurotrophic factor plays a critical role in contextual fear conditioning.

In this study, brain-derived neurotrophic factor (BDNF) heterozygous knock-outs were tested on fear conditioning, and their wild-type littermates were used as controls. Results showed that BDNF(+/-) mice are impaired in contextual learning, whereas tone learning remains intact. Because BDNF is involved in synaptic transmission and contextual learning is hippocampal dependent, we hypothesized that this deficit is attributable to abnormal BDNF-modulated synaptic plasticity in the hippocampus.

Genetic and environmental contributions to the development of alcohol dependence in male twins.

Background: Information on the heritability of the development of alcohol dependence could provide a better understanding of the importance of genetic components in disease transition.

Objective: To examine the genetic and nongenetic contributions to the age at onset of regular alcohol use, the age at diagnosis of alcohol dependence, and the transition from regular alcohol use to alcohol dependence.

Design: Classic twin study.

Infusion of beta-endorphin improves insulin resistance in fructose-fed rats.

In an attempt to probe the effect of beta-endorphin on insulin resistance, we used Wistar rats that were fed fructose-rich chow to induce insulin resistance. Insulin action on glucose disposal rate (GDR) was measured using the hyperinsulinemic euglycemic clamp technique, in which glucose (variable), insulin (40 mU/kg/min), and beta-endorphin (6 ng/kg/min) or vehicle were initiated simultaneously and continued for 120 min. A marked reduction in insulin-stimulated GDR was observed in fructose-fed rats compared to normal control rats.

Detection of SARS-associated coronavirus in throat wash and saliva in early diagnosis.

The severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is thought to be transmitted primarily through dispersal of droplets, but little is known about the load of SARS-CoV in oral droplets. We examined oral specimens, including throat wash and saliva, and found large amounts of SARS-CoV RNA in both throat wash (9.58 x 10(2) to 5.

Increase of anti-oxidation by exercise in the liver of obese Zucker rats.

1. The effects of endurance training on the anti-oxidant status in diabetes were studied using obese Zucker rats. 2.

Disease-specific B Cell epitopes for serum antibodies from patients with severe acute respiratory syndrome (SARS) and serologic detection of SARS antibodies by epitope-based peptide antigens.

Severe acute respiratory syndrome (SARS) has emerged as a highly contagious, sometimes fatal disease. To find disease-specific B cell epitopes, phage-displayed random peptide libraries were panned on serum immunoglobulin (Ig) G antibodies from patients with SARS. Forty-nine immunopositive phage clones that bound specifically to serum from patients with SARS were selected.

Activation of alpha1A-adrenoceptors by genistein at concentrations lower than that to inhibit tyrosine kinase in cultured C2C12 cells.

Genistein, an isoflavonoid natural product, is widely used to inhibit protein tyrosine kinase (PTK). In the present study, we investigated the possible influence of genistein on alpha (1)-adrenoceptors (AR) in cultured C2C12 cells. Genistein enhanced the uptake of radioactive glucose into C2C12 cells in a concentration-dependent manner.

Identification and characterization of the acidic pH binding sites for growth regulatory ligands of low density lipoprotein receptor-related protein-1.

The type V TGF-beta receptor (TbetaR-V) plays an important role in growth inhibition by IGFBP-3 and TGF-beta in responsive cells. Unexpectedly, TbetaR-V was recently found to be identical to the LRP-1/alpha(2)M receptor; this has disclosed previously unreported growth regulatory functions of LRP-1. Here we demonstrate that, in addition to expressing LRP-1, all cells examined exhibit low affinity but high density acidic pH binding sites for LRP-1 growth regulatory ligands (TGF-beta(1), IGFBP-3, and alpha(2)M(*)).

The plasma glucose lowering action of tetrandrine in streptozotocin-induced diabetic rats.

The effect of tetrandrine, an active principle of Stephaniae tetrandrae, on the plasma glucose level in streptozotocin-induced diabetic rats (STZ-diabetic rats) was investigated. A single intravenous injection of tetrandrine decreased the plasma glucose in a dose-dependent manner in STZ-diabetic rats. Moreover, tetrandrine (1.

Cellular growth inhibition by TGF-beta1 involves IRS proteins.

In Mv1Lu cells, insulin partially reverses transforming growth factor-beta1 (TGF-beta1) growth inhibition in the presence of alpha5beta1 integrin antagonists. TGF-beta1 appears to induce phosphorylation of IRS-2 in these cells; this is inhibited by a TGF-beta antagonist known to reverse TGF-beta growth inhibition. Stable transfection of 32D myeloid cells (which lack endogenous IRS proteins and are insensitive to growth inhibition by TGF-beta1) with IRS-1 or IRS-2 cDNA confers sensitivity to growth inhibition by TGF-beta1; this IRS-mediated growth inhibition can be partially reversed by insulin in 32D cells stably expressing IRS-2 and the insulin receptor (IR).

Signals in the activation of opioid mu-receptors by loperamide to enhance glucose uptake into cultured C2C12 cells.

In an attempt to understand the signal pathways of opioid mu-receptors for glucose metabolism, we used loperamide to investigate the glucose uptake into the myoblast C2C12 cells. Loperamide enhanced the uptake of radioactive deoxyglucose into C2C12 cells in a concentration-dependent manner that was abolished in cells pre-incubated with naloxone or naloxonazine at concentrations sufficient to block opioid mu-receptors. Pharmacological inhibition of phospholipase C (PLC) by U73122 resulted in a concentration-dependent decrease in loperamide-stimulated uptake of radioactive deoxyglucose into C2C12 cells.

Dehydroepiandrosterone sulfate (DHEAS) and health: does the relationship differ by sex?

This study uses data from a large, nationally representative sample of older Taiwanese (aged 54 and older in 2000) to investigate sex differences in the relationship between DHEAS and various health outcomes. Data collection included an individual interview, a physical examination, and samples of blood and (12-h) urine. Regression models of health outcomes on DHEAS are estimated in two steps: first, including only controls for age and sex as well as an interaction between DHEAS and sex; and second, adding covariates likely to be related to both DHEAS and health outcomes (e.

Activation of imidazoline receptor by agmatine to lower plasma glucose in streptozotocin-induced diabetic rats.

In the present study, we use agmatine, an endogenous ligand, to investigate the role of imidazoline receptor in plasma glucose regulation in streptozotocin-induced diabetic rats (STZ-diabetic rats). After injection into the central lateral ventral (i.c.

Colleges respond to student binge drinking: reducing student demand or limiting access.

Administrators at 68% of 4-year colleges nationwide (N = 747) responded to a survey concerning the types of programs and policies they used in response to students' heavy drinking. Most schools conducted targeted alcohol education and invested in institutional prevention efforts; half conducted social norms campaigns; a sizeable minority restricted alcohol on campus. Schools that focused on demand reduction were less likely to ban alcohol use.

Isosteviol acts on potassium channels to relax isolated aortic strips of Wistar rat.

Isosteviol is a derivative of stevioside, a constituent of Stevia rebaudiana, which is commonly used as a noncaloric sugar substitute in Japan and Brazil. In the present study, the role of potassium channels in the vasodilator effect of isosteviol was investigated using potassium channel blockers on isosteviol-induced relaxation of isolated aortic rings prepared from Wistar rats. Isosteviol dose-dependently relaxed the vasopressin (10(-8) M)-induced vasoconstriction in isolated aortic rings with or without endothelium.

Mediation of beta-endorphin by the isoflavone puerarin to lower plasma glucose in streptozotocin-induced diabetic rats.

We investigate the mechanism(s) of plasma glucose lowering action of puerarin in streptozotocin-induced diabetic rats (STZ-diabetic rats). Puerarin at the effective dosage to lower higher plasma glucose increased plasma beta-endorphin-like immunoreactivity (BER) in STZ-diabetic rats. Both effects of puerarin were abolished by the pretreatment with prazosin.

Isosteviol as a potassium channel opener to lower intracellular calcium concentrations in cultured aortic smooth muscle cells.

Isosteviol is a derivative of stevioside, a constituent of Stevia rebaudiana, and is commonly used as a non-caloric sugar substitute in Japan and Brazil. The present study attempted to elucidate the role of potassium (K (+)) channels in the action of isosteviol on intracellular calcium concentrations ([Ca (2+)]i) in cultured vascular smooth muscle (A7r5) cells using the Ca (2+)-sensitive dye Fura-2 as an indicator. The increase of [Ca (2+)]i in A7r5 cells produced by vasopressin (1 micromol/L) or phenylephrine (1 micromol/L) was attenuated by isosteviol from 0.

Requirement of protein phosphatase 5 in DNA-damage-induced ATM activation.

The checkpoint kinase ATM is centrally involved in the cellular response to DNA double-strand breaks. However, the mechanism of ATM activation during genotoxic stress is only partially understood. Here we report a direct regulatory linkage between the protein serine-threonine phosphatase 5 (PP5) and ATM.

Frosted branch angiitis in two Chinese young girls.

We examined 2 relatively healthy young girls who presented with acute red eyes and blurred vision. Each patient developed thick, inflammatory infiltrates surrounding the retinal vessels creating the appearance of frosted tree branches in both eyes. Marked inflammatory reactions with cells and flare were noted in anterior chambers.

Effect of tetramethylpyrazine on potassium channels to lower calcium concentration in cultured aortic smooth muscle cells.

1. Tetramethylpyrazine (TMP) is one of the active principles contained in Ligusticum chuanxiong Hort. (Umbelliferae), a herb that has been used widely in China to treat vascular disorders.

Loperamide increases glucose ultilization in streptozotocin-induced diabetic rats.

1. Loperamide has an ability to lower the plasma glucose concentration in streptozotocin (STZ)-induced diabetic rats. In the present study, we investigated the molecular mechanisms by which loperamide regulates plasma glucose concentrations in the absence of insulin.