Search results for "CHROMATOGRAPHY"

Outcome of pregnancy in type 1 diabetic patients treated with insulin lispro or regular insulin: an Italian experience.

2008

Some studies have shown that fetal outcome observed in patients using insulin lispro is much the same as in pregnant women using regular insulin. This study aims to analyze the Italian data emerging from a multinational, multicenter, retrospective study on mothers with type 1 diabetes mellitus before pregnancy, comparing those treated with insulin lispro for at least 3 months before and 3 months after conception with those treated with regular insulin. The data collected on pregnant women with diabetes attending 15 Italian centers from 1998 to 2001 included: HbA1c at conception and during the first and third trimesters, frequency of severe hypoglycemic episodes, spontaneous abortions, mode …

Epithelium-derived inhibition of [3H]acetylcholine release from the isolated guinea-pig trachea

1990

To investigate presynaptic, regulatory mechanisms on parasympathetic nerve fibres innervating the airways, the release of newly-synthesized [3H]acetylcholine from the isolated trachea was studied. Reverse phase HPLC followed by liquid scintillation spectrometry was used to separate and quantify the radioactive compounds choline, phosphorylcholine and acetylcholine in the incubation medium and the tissue. During the incubation of the tracheae with [3H]choline a significant synthesis of [3H]acetylcholine (35,000 dpm/preparation) and [3H]phosphorylcholine (500,000 dpm/preparation) occurred. In epithelium-deficient tracheae the formation of [3H]phosphorylcholine was enhanced, whereas the conten…

Platelet membrane fluidity, platelet membrane lipid pattern and platelet cytosolic Ca2+ content in subjects with vascular atherosclerotic disease

1994

In a group of subjects with vascular atherosclerotic disease (V AD) we examined the platelet membrane fluidity (obtained marking intact resting platelets with TMA-DPH), the platelet membrane cholesteroVphospholipid ratio (CIPL using column chromatography), the platelet membrane individual phospholipids (employing the thin layer chromatography) and the platelet cytosolic Ca2+ content (evaluated marking intact resting platelets with Fura 2-AM). From the obtained data, it is evident that platelet membrane fluidity differentiates normals from V AD subjects. Platelet membrane lipid pattern (CIPL and individual phospholipids) and cytosolic Ca2+ content do not discriminate normals from V AD subjec…

Lack of autoreceptor mediated regulation of the spontaneous dopamine turnover in the isolated neurointermediate lobe of the rat pituitary gland in vi…

1990

Isolated neurointermediate lobes of the rat pituitary gland were incubated in Krebs-HEPES solution and the spontaneous outflow of endogenous dopamine and its metabolites (DOPAC, HVA and MOPET) was determined by HPLC with electrochemical detection. The spontaneous outflow of dopamine metabolites (about 1500 fmol/10 min) largely exceeded that of dopamine (about 60 fmol/10 min). Apomorphine concentration-dependently (IC50, 205 nmol/l) reduced the spontaneous outflow of the dopamine metabolites. The effect of apomorphine developed slowly and was progressive over an observation period of 70 min. After 1 h of exposure to a maximall effective concentration of apomorphine (10 mumol/l), the outflow …

Release of endogenous 3,4-dihydroxyphenylethylamine and its metabolites from the isolated neurointermediate lobe of the rat pituitary gland. Effects …

1986

: Isolated rat neurointermediate lobes were incubated in vitro. The release of 3,4-dihydroxyphenylethylamine (dopamine, DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and methoxyphenylethanol (MOPET) was determined by HPLC with electrochemical detection. Under resting conditions, the outflow of metabolites was 35–50 times that of DA. HVA accounted for 50%, DOPAC for 45%, and MOPET for 5% of the metabolites. Although an equivalent of 40–50% of the tissue DA content was released per hour as metabolites, the tissue DA content was not reduced after 110 min of incubation. The spontaneous outflow of DA and its metabolites was not affected by the DA uptake inhibitor GBR 12921 (1…

Endocannabinoid anandamide mediates hypoxic pulmonary vasoconstriction

2013

Endocannabinoids are important regulators of organ homeostasis. Although their role in systemic vasculature has been extensively studied, their impact on pulmonary vessels remains less clear. Herein, we show that the endocannabinoid anandamide (AEA) is a key mediator of hypoxic pulmonary vasoconstriction (HPV) via fatty acid amide hydrolase (FAAH)-dependent metabolites. This is underscored by the prominent vasoconstrictive effect of AEA on pulmonary arteries and strongly reduced HPV in FAAH(-/-) mice and wild-type mice upon pharmacological treatment with FAAH inhibitor URB597. In addition, mass spectrometry measurements revealed a clear increase of AEA and the FAAH-dependent metabolite arac…

Search for autoantibodies to the human bradykinin B2 receptor.

1997

An exploratory study of two Caco-2 cell models for oral absorption: A report on their within-laboratory and between-laboratory variability, and their…

2010

In 2005, the European Centre for the Validation of Alternative Methods (ECVAM) sponsored a study aimed at evaluating the reproducibility (between-laboratory and within-laboratory variability) and the predictive capacity of two in vitro cellular systems — the Caco-2/ATCC parental cell line and the Caco-2/TC7 clone — for estimating the oral fraction absorbed (Fa) in humans. Two laboratories, both of which had experience with Caco-2 cultures, participated in the study. Ten test chemicals with documented in vivo oral absorption data were selected. Atenolol, cimetidine and propranolol were included as reference compounds for low, medium and high intestinal absorption, respectively. Transport ex…

Characterization of endogenous noradrenaline release from intact and epithelium-denuded rat isolated trachea.

1991

1. Overflow of endogenous noradrenaline (NA) from the in vitro incubated rat trachea evoked by two periods of electrical field stimulation (S1, S2 at 3 or 15 Hz) or by high potassium (60 mM) was determined by high performance liquid chromatography (h.p.l.c.) with electrochemical detection. 2. In the presence of the neuronal uptake inhibitor desipramine, the alpha 2-adrenoceptor antagonist, yohimbine, enhanced the overflow of NA evoked by stimulation at 3 Hz by about 100% suggesting the presence of presynaptic inhibitory autoreceptors on the sympathetic nerves innervating the trachea. 3. When desipramine and yohimbine were present throughout the experiments, the overflow of NA evoked by the …

Screening for colorectal cancer with immunochemical faecal occult blood tests.

2012

Population-based studies have shown that guaiac faecal occult blood testing followed by colonoscopy in case of positivity can reduce colorectal cancer mortality. However these tests have been criticised for their fairly low sensitivity. For this reason attention has been given to alternative tests. The aim of this paper is to review the evidence for screening for colorectal cancer using qualitative immunochemical faecal occult blood tests. For the complete range of tested cut-off values, immunochemical faecal occult blood tests lead to higher diagnostic yield, improved sensitivity and greater participation. The optimal number of samples and the optimal cut-off value has to suit local resour…