Search results for "Lability"
showing 10 items of 802 documents
Gastric emptying of indigestible tablets in relation to composition and time of ingestion of meals studied by metal detector.
1991
Enteric-coated tablets leave the stomach mainly during the interdigestive phase. Composition as well as time of ingestion of meals may influence their gastric emptying considerably. In 12 normal volunteers gastric emptying of a plastic tablet with a metal core was followed by a metal detector in relation to different compositions and various times of ingestion of meals. With an empty stomach and after ingestion of 250 ml water, the mean time for gastric emptying of the tablet was 38 +/- 11 min (mean +/- SEM) and 38 +/- 8 min. Two hundred fifty milliliters of milk (652 kJ) and a formula diet (1000 kJ) delayed gastric emptying time to 128 +/- 14 and 152 +/- 6 min, respectively (P less than 0.…
Enriched cereal bars are more effective in increasing plasma quercetin compared with quercetin from powder-filled hard capsules
2011
The flavonol quercetin, is one of the major flavonoids found in edible plants. The bioavailability of quercetin in humans may be influenced by the food matrix in which it is consumed as well as by its chemical and physical form. The objective of the present study was to investigate the biokinetics of quercetin from quercetin-enriched cereal bars and quercetin powder-filled hard capsules. In a randomised, single-blinded, diet-controlled cross-over study, six healthy women aged 22–28 years took a single oral dose of approximately 130 mg quercetin equivalents from either quercetin-enriched cereal bars (containing 93·3 % quercetin aglycone plus 6·7 % quercetin-4′-glucoside) or quercetin powder-…
Oral versus intravenous vinorelbine: clinical safety profile
2005
The availability of chemotherapeutic drugs administrable by oral route represents a step forward in the management of cancer patients. Among oral agents, vinorelbine is particularly interesting for its pharmacological characteristics and clinical efficacy. Oral vinorelbine is rapidly absorbed (1.5-3 hours) with an elimination half-life of approximately 40 hours. It shows a low level of binding to plasma proteins (13%), is highly bound to platelets (78%) and has a hepatic metabolism and an absolute bioavailability of 40% with a moderate and similar interpatient variability for the two forms. Food has no influence on the pharmacokinetic profile of oral vinorelbine even if nausea/vomiting is l…
Pharmacokinetics of Droloxifene and Its Metabolites in Breast Cancer Patients
1991
Pharmacokinetics and metabolism of droloxifene, a new antiestrogenic drug, have been investigated by single- and multiple-dose studies in postmenopausal patients with advanced breast cancer. Short terminal elimination half-life, low accumulation, and improved drug tolerability are the most striking features of this safe and effective new antiestrogen. Bioequivalence of film-coated tablet, tablet, and standard solution of droloxifene has been shown. The concentrations of droloxifene and its metabolites have been determined by a highly selective HPLC method.
Comparison of high-pressure liquid chromatography (HPLC) and Griess reagent-spectroscopic methods for the measurement of nitrate in serum from health…
2008
Bioavailability of NO can be estimated by measuring the concentration of nitrate (NO(3)) in serum. However, the methods used for the measurement NO(3) in plasma or serum show a great degree of variation. Therefore, we compared two analytical methods for the measurement of NO(3) in serum.The concentration of NO(3) in 600 serum samples collected from healthy individuals was determined by the HPLC and by the Griess reagent-spectroscopic method.The concentration of NO(3) in the samples was 29.4+/-16.1 micromol/L and 26.2+/-14.0 micromol/L (mean+/-SD) measured by HPLC and Griess reagent-spectroscopic method respectively (p0.0001). We detected a significant correlation between the two methods (R=…
Properties of Resveratrol:In VitroandIn VivoStudies about Metabolism, Bioavailability, and Biological Effects in Animal Models and Humans
2015
Plants containing resveratrol have been used effectively in traditional medicine for over 2000 years. It can be found in some plants, fruits, and derivatives, such as red wine. Therefore, it can be administered by either consuming these natural products or intaking nutraceutical pills. Resveratrol exhibits a wide range of beneficial properties, and this may be due to its molecular structure, which endow resveratrol with the ability to bind to many biomolecules. Among these properties its activity as an anticancer agent, a platelet antiaggregation agent, and an antioxidant, as well as its antiaging, antifrailty, anti-inflammatory, antiallergenic, and so forth activities, is worth highlightin…
Cocoa polyphenols and their potential benefits for human health.
2012
This paper compiles the beneficial effects of cocoa polyphenols on human health, especially with regard to cardiovascular and inflammatory diseases, metabolic disorders, and cancer prevention. Their antioxidant properties may be responsible for many of their pharmacological effects, including the inhibition of lipid peroxidation and the protection of LDL-cholesterol against oxidation, and increase resistance to oxidative stress. The phenolics from cocoa also modify the glycemic response and the lipid profile, decreasing platelet function and inflammation along with diastolic and systolic arterial pressures, which, taken together, may reduce the risk of cardiovascular mortality. Cocoa polyph…
Comparison between the shifted-Laplacian preconditioning and the controllability methods for computational acoustics
2010
Processes that can be modelled with numerical calculations of acoustic pressure fields include medical and industrial ultrasound, echo sounding, and environmental noise. We present two methods for making these calculations based on Helmholtz equation. The first method is based directly on the complex-valued Helmholtz equation and an algebraic multigrid approximation of the discretized shifted-Laplacian operator; i.e. the damped Helmholtz operator as a preconditioner. The second approach returns to a transient wave equation, and finds the time-periodic solution using a controllability technique. We concentrate on acoustic problems, but our methods can be used for other types of Helmholtz pro…
Amino-phosphanes in RhI-Catalyzed Hydroformylation: Hemilabile Behavior of P,N Ligands under High CO Pressure and Catalytic Properties
2005
International audience; The catalytic properties of rhodium complexes containing the α-, β-, or γ-amino-phosphane ligands Ph2PCH2NEt2 (α-P,N-1), Ph2PCH(Ar)NHPh [α-P,N-2; Ar = η6(o-C6H4Cl)Cr(CO)3], Ph2PCH2NPh2 (α-P,N-3), Ph2PCH2CH(Ph)NHPh (β-P,N), Ph2PCH2(o-C6H4–NMe2) (γ-P,N-1), Ph2PCH(o-C6H4–CH2NHPh) (γ-P,N-2), and the α,β-diamino-phosphane ligand Et2NCH2P(Ph)CH2CH(Ph)NHPh (α,β-N,P,N), in styrene hydroformylation have been examined. The results show that the activity increases when the number of backbone carbon atoms linking P and N decreases from 3 to 1. IR and 31P HPNMR studies in solution show that all P,N ligands adopt exclusively a κ1-P coordination mode in rhodium chloride carbonyl co…
In Vitro Bioavailability of Phenolic Compounds from Five Cultivars of Frozen Sweet Cherries (Prunus aviumL.)
2008
The bioavailability of phenolic compounds from five cultivars of frozen sweet cherries was assessed by a digestion process involving pepsin-HCl digestion (to simulate gastric digestion) and pancreatin digestion with bile salts (to simulate small intestine conditions) and dialyzed to assess serum- and colon-available fractions. After pepsin digestion, the % recovery of total phenolics, relative to the original starting material, increased, whereas the % anthocyanins did not change. Following pancreatic digestion and dialysis, the total phenolics in the IN (serum-available) fraction was about 26–30% and the OUT (colon-available) fraction was about 77–101%. The anthocyanin content in the IN fr…