Search results for "beta"
showing 10 items of 3374 documents
In vitro reprogramming of pancreatic alpha cells towards a beta cell phenotype following ectopic HNF4α expression
2015
There is currently a shortage of organ donors available for pancreatic beta cell transplantation into diabetic patients. An alternative source of beta cells is pre-existing pancreatic cells. While we know that beta cells can arise directly from alpha cells during pancreatic regeneration we do not understand the molecular basis for the switch in phenotype. The aim of the present study was to investigate if hepatocyte nuclear factor 4 alpha (HNF4α), a transcription factor essential for a normal beta cell phenotype, could induce the reprogramming of alpha cells towards potential beta cells. We utilised an in vitro model of pancreatic alpha cells, the murine αTC1-9 cell line. We initially chara…
Bisoprolol and captopril effects on insulin receptor tyrosine kinase activity in essential hypertension.
1998
Angiotension converting enzyme (ACE) inhibitors and beta-blockers have been reported to possess disparate effects on insulin sensitivity. The aim of this study was to study the effects of the selective beta-1 blocker bisoprolol and of the ACE inhibitor captopril on cellular insulin action in hypertensive individuals. After washout, 12 mild to moderate essential hypertensives were randomized in a double-blind manner to 5 mg bisoprolol daily or 25 mg captopril twice daily for 8 weeks. Erythrocyte insulin binding and insulin-stimulated tyrosine kinase (TK) activity were measured before and after therapy. Both agents decreased diastolic blood pressure significantly (bisoprolol 96.5+/-0.9 to 87.…
The release of choline from phospholipids mediated by beta-adrenoceptor activation in isolated hearts.
1986
The resting efflux of choline into the perfusate (Tyrode's solution) of isolated hearts was equal to the rate, at which choline was liberated from phospholipid degradation (Lindmar et al. 1986). Infusion of isoprenaline (2 X 10(-7) mol/l), forskolin (1-3 X 10(-6) mol/l) or 3-isobutyl-1-methylxanthine (IBMX; 3 X 10(-4) mol/l) for 40 min markedly enhanced the efflux of choline. The increase was linear during the experimental period and, in the case of isoprenaline, was blocked by 3 X 10(-7) mol/l atenolol. In the guinea-pig heart, IBMX at a threshold concentration of 10(-4) mol/l shifted the concentration-response curve for the effect of forskolin on the efflux of choline to the left by one l…
Histamine and spontaneously released mast cell granules affect the cell growth of human hepatocellular carcinoma cells
2007
The role of mast cells in tumor growth is still controversial. In this study we analyzed the effects of both histamine and pre-formed mediators spontaneously released by mast cells on the growth of two human hepatocellular carcinoma cell lines, HA22T/VGH and HuH-6, with different characteristics of differentiation, biological behavior and genetic defects. We showed that total mast cell releasate, exocytosed granules (granule remnants) and histamine reduced cell viability and proliferation in HuH-6 cells. In contrast, in HA22T/VGH cells granule remnants and histamine induced a weak but significant increase in cell growth. We showed that both cell lines expressed histamine receptors H(1) and …
Treatment of Tako-tsubo cardiomyopathy
2008
N.A.
Special Considerations for Antihypertensive Agents in Dialysis Patients
2010
Hypertension is present in most patients with end-stage renal disease and likely contributes to the premature cardiovascular disease in dialysis patients. Previous practice guidelines have recommended that, in patients on chronic dialysis, blood pressure (BP) should be reduced below 130/80 mm Hg. This is based on opinions but not strong evidence, since no concrete information exists about which BP values should be the parameter to follow and which should be the target BP values. The majority of the antihypertensive agents can be used in this population, but the pharmacokinetics altered by the impaired kidney function and dialyzability influence the appropriate dosage as well as the time and…
Effects of Norepinephrine and Cardiotrophin-1 on Phospholipase D Activity and Incorporation of Myristic Acid Into Phosphatidylcholine in Rat Heart
2004
The present study is part of a project on phospholipase D (PLD) in cardiac hypertrophy and analyzed effects on PLD activity of two growth stimuli, norepinephrine (NE) and cardiotrophin-1 (CT-1), in incubated rat heart. Phosphatidylcholine (PC) was labeled by 3H-myristic acid. PLD produced 3H-phosphatidylethanol (3H-PEth) from 3H-PC in the presence of ethanol and maintained a basal formation of 3H-PEth. Short-term and long-term exposure to NE for 2 or 13 h, respectively, enhanced the formation of 3H-PEth, which was blocked by prazosin. Long-term pretreatment with NE or CT-1 increased the incorporation of 3H-myristic acid into PC, which was blocked by atenolol. When the 3H-PEth formation was …
Hypolipidaemic effects of fenofibrate and fasting in the herbivorous grass carp (Ctenopharyngodon idella) fed a high-fat diet
2008
We investigated whether the hypolipidaemic effect of fenofibrate and fasting observed in most omnivorous mammals may also apply to herbivorous fish. Grass carp (Ctenopharyngodon idella) fed a high-fat (8 %) diet exhibited a marked increase in blood lipids and body fat after 6 weeks. They were then treated with fenofibrate (100 mg/kg body weight) in the same high-fat diet for 2 weeks, followed by fasting for 1 week. Plasma lipid concentration, body fat amount, fatty acid composition, plasma thiobarbituric acid-reactive substances and some parameters related to hepatic fatty acid oxidation were measured, and liver samples were stained for histological examination. Fenofibrate treatment decrea…
A systematic review on the efficacy and safety of chloroquine for the treatment of COVID-19
2020
Purpose COVID-19 (coronavirus disease 2019) is a public health emergency of international concern. As of this time, there is no known effective pharmaceutical treatment, although it is much needed for patient contracting the severe form of the disease. The aim of this systematic review was to summarize the evidence regarding chloroquine for the treatment of COVID-19. Methods PubMed, EMBASE, and three trial Registries were searched for studies on the use of chloroquine in patients with COVID-19. Results We included six articles (one narrative letter, one in-vitro study, one editorial, expert consensus paper, two national guideline documents) and 23 ongoing clinical trials in China. Chloroqui…
COVID-19 and obesity: links and risks
2020
Applicable to the fields of endocrinology, as well as for specialists in cardiovascular disease (CVD), obesity has numerous cardiometabolic unfavorable consequences. Obesity is by far the leading c...