Search results for "Chromatography"
showing 10 items of 5037 documents
Synthesis of fluorine-18 labeled sulfonureas as ?-cell imaging agents
2001
Tolbutamide (1) and glyburide (7) are hypoglycemic drugs used to stimulate insulin secretion in type 2 diabetic patients. We have synthesized their fluorine-18 labeled analogs, 1-[(4-[ 18 F]fluorobenzenesulfonyl)]-3-butyl]urea (p-[ 18 F]fluorotolbutamide, 3a) and N-{4-[β-(2-[ 18 F]fluoroethoxybenzene carboxamido)ethyl]benzenesulfonyl)-N'-cyclohexylurea (2-[ 18 F]fluoroethoxyglyburide, 6a) as β-cell imaging agents. Compound 3a was synthesized via two approaches: One-step synthesis via nucleophilic substitution of p-nitrotolbutamide (2) with K[ 18 F]/Kryptofix 2.2.2 in either CH 3 CN or DMSO gave a complicated mixture; a two-step synthesis via preparation and reaction of 4-[ 18 F]fluorobenzen…
Moderate consumption of beer reduces liver triglycerides and aortic cholesterol deposit in LDLr-/- apoB100/100 mice.
2006
This study was designed to address the effects of a moderate consumption of beer on serum and liver lipid parameters and on the development of aortic lesions in a mouse model associated with a human atherogenic lipoprotein profile. LDLr(-/-) apoB(100/100) mice received each day during 12 weeks either water, mild beer (0.570g of ethanol/kg of body weight) or ethanol-free beer in a single pure dose. Serum and liver lipid parameters were analyzed and atherosclerotic lesions were estimated in heart and aorta through their total cholesterol content. mRNA levels of enzymes and receptors involved in lipoprotein uptake, in fatty acid esterification and oxidation, and in reverse cholesterol transpor…
Halogenated Anesthetics Determination in Urine by SPME/GC/MS and Urine Levels Relationship Evaluation with Surgical Theatres Contamination
2014
In this work, a new sensitive analytical method has been developed and evaluated for the determination of the most commonly used gaseous anesthetics, desflurane, sevoflurane, and this latter’s hepatic metabolite hexafluoroisopropanol (HFIP) in the urine. In addition, an evaluation of anesthetics exposition on the urine levels of a small population of surgical operators has been performed and results are briefly discussed.
Aldosterone biosynthesis induced by ACTH and angiotensin II in newborn rat adrenocortical cells transfected by c-EJ-Ha-ras oncogene
1991
Abstract Adrenocortical cells were obtained by fractionated trypsination of newborn rat adrenal glands and transfected with a plasmid containing the EJ T24 -Ha-ras oncogene. Isolation of adhesive cells led to a proliferative cell line with an overexpression of 21 kDa ras protein. These cells incubated with corticosterone or deoxycorticosterone as the precursor produced a high level of 18-hydroxycorticosterone and aldosterone as identified by gas chromatography- mass spectrometry. ACTH and angiotensin II increased the basal production of aldosterone nineteen-fold and six-fold respectively. Under ACTH stimulation the ratio between aldosterone and 18-hydroxycorticosterone production was 1:3. T…
Carboxyl nonsteroidal anti-inflammatory drugs are efficiently glucuronidated by microsomes of the human gastrointestinal tract.
2004
Limited studies have been carried out on the biotransformation of carboxyl nonsteroidal anti-inflammatory drugs (NSAIDs) in the liver. However, the role of the intestine in NSAID metabolism has not been investigated. In this report, the contribution of UDP-glucuronosyltransferases (UGTs) in the human gastrointestinal (GI) tract from five donors to the glucuronidation of the NSAIDs, RS-ketoprofen, S-naproxen, RS- and S-etodolac, was investigated. UGT activity and, for some donors, mRNA levels were evaluated. All NSAIDs were glucuronidated throughout the GI tract; however, glucuronidation was low in stomach and duodenum as compared to the remainder of the intestine. RT-PCR analysis demonstrat…
Compatibility of irinotecan-loaded DC Bead with different volumes and types of non-ionic contrast media.
2015
Objectives Irinotecan-loaded microspheres are used for simultaneous embolisation and chemotherapy of liver metastases of colorectal carcinoma. The aim of the study was to evaluate the compatibility of recently introduced DC Bead M1 (bead size 70–150 µm) loaded with irinotecan after admixture with different types and volumes of non-ionic contrast media over a maximum period of 24 h and storage at room temperature. Methods Test suspensions were prepared by loading 2 mL DC Bead M1 with 100 mg irinotecan within 2 h. The loading efficiency was determined by measuring the concentrations of irinotecan in the excess solutions via a reversed phase high pressure liquid chromatography (RP-HPLC) assay …
An Evaluation of Fibrin(ogen) Determinants of Thromboelastography
2011
Abstract Abstract 2251 Thromboelastography (TEG) was used in ∼200 studies published in 2009, is mainly used for global blood coagulation assessment, and is thrombin and fibrinogen concentration-dependent. Reflecting the time course of fibrin polymerization, TEG measures lag time, rate, and maximum amplitude (MA) of clot stiffness, and is substantially enhanced by platelets. To identify more specific fibrin(ogen) determinants potentially relevant to interpretation we investigated MA under different TEG conditions. The procedure utilizes a polymethylmethacrylate (hydrophobic surface) cup and pin set, the cup oscillating through 4° 45' (6 cycles/minute). The pin (sensor) is suspended via a tor…
�ber die Eignung spektralanalytischer Methoden zur Bestimmung des Blutfleckenalters
1977
The spectrophotometric methods of Kind et al. and Kleihauer et al. were checked by more than 900 experiments on 85 blood stains on different material (cotton, nyltest and paper) from native and citrate blood, aged at room temperature up to 5 years. As a result, the variation of values within one age-group exceeded the differences between the values of samples of different age. Therefore, both methods are thought to be unsuitable for the estimation of blood stain age in practical forensic medicine, although the general trend described by the above authors could be confirmed.
Physicochemical stability of irinotecan injection concentrate and diluted infusion solutions in PVC bags
2000
Purpose. To determine the physicochemical stability of irinotecan injection concentrate and irinotecan infusion solutions after dilution in two commonly used infusion fluids (0.9% sodium chloride, 5% dextrose) in PVC bags, stored under refrigeration (2-8°C) or at room temperature either light protected or exposed to light. Methods. Stability of irinotecan injection concentrate was determined in the original amber glass vials. Diluted irinotecan infusion solutions were aseptically prepared by further dilution of irinotecan stock solution with either 0.9% sodium chloride or 5% dextrose in PVC bags, in amounts yielding irinotecan concentrations of 0.4, 1.0, or 2.8 mg/ml. Test solutions were s…
pH stability of ophthalmic solutions.
2004
Background In this study, we evaluated the pH value of 17 ophthalmic solutions, and we investigated whether the pH of these solutions changed over time after the bottle was opened. Methods Fifteen bottles of each type of solution were chosen at random from different production lots. A 0.05-ml increment was taken from each bottle and was measured daily using a micropH 2002 Crison pH-meter over a period of 30 days. Results The results revealed differences between the pH values of the solutions; nine solutions presented pH values within ocular comfort range and eight solutions presented pH values between 3.5 and 6.4. Ten solutions presented non-statistically significant variations over time ( …