scholarly journals In vitro release of arachidonic acid and in vivo responses to respirable fractions of cotton dust.

1986 ◽  
Vol 66 ◽  
pp. 87-90
Author(s):  
T A Thomson ◽  
J H Edwards ◽  
T S Al-Zubaidy ◽  
R C Brown ◽  
A Poole ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
In Vitro Release ◽  
Cotton Dust ◽  
Vitro Release

Effects of arachidonic acid and indomethacin on the in vitro release of prostaglandins by aortic strips of spontaneously hypertensive rats

1978 ◽  
Vol 56 (3) ◽  
pp. 509-511 ◽  
Author(s):  
R. Quirion ◽  
F. Rioux ◽  
D. Regoli
Keyword(s):  
Arachidonic Acid ◽  
Intravenous Injection ◽  
Spontaneously Hypertensive Rats ◽  
In Vitro Release ◽  
Hypotensive Effect ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive ◽  
Vitro Release

Aortic strips removed from spontaneously hypertensive (SH) rats and preincubated with arachidonic acid (1.0 × 10−5 g/ml) for 15 min produced two times more prostaglandin (PG) like material than aortae unexposed to the precursor of PG biosynthesis. The stimulating effect of arachidonic acid was largely inhibited by indomethacin (1.0 × 10−5 g/ml). Also, the release of PG-like material by aortic strips derived from SH rats treated with an intravenous injection of indomethacin (10 mg/kg) was inhibited by 74% compared with the control tissues. These results raised the possibility that the in vivo conversion of arachidonic acid by large arteries of SH rats may contribute to the hypotensive effect of this PG precursor in SH rats.

Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

1987 ◽  
Vol 57 (02) ◽  
pp. 201-204 ◽  
Author(s):  
P Y Scarabin ◽  
L Strain ◽  
C A Ludlam ◽  
J Jones ◽  
E M Kohner
Keyword(s):  
In Vitro Release ◽  
Mean Value ◽  
Reliable Estimate ◽  
Diabetic Patients ◽  
Single Measurement ◽  
Diabetic Population ◽  
The Difference ◽  
Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

Development, in vitro and in vivo Evaluations of Solid-Lipid Microparticles based on Solidified Micellar Carrier System for Oral Delivery of Cefepime

2017 ◽  
Vol 10 (1) ◽  
pp. 3582-3593
Author(s):  
Chukwuebuka Umeyor ◽  
Uchechukwu Nnadozie ◽  
Anthony Attama
Keyword(s):  
Oral Delivery ◽  
In Vitro Release ◽  
Carrier System ◽  
Solid Lipid ◽  
Solid Lipid Microparticles ◽  
Release Study ◽  
Lipid Microparticles ◽  
Vitro Release

This study seeks to formulate and evaluate a solid lipid nanoparticle-based, solidified micellar carrier system for oral delivery of cefepime. Cefepime has enjoyed a lot of therapeutic usage in the treatment of susceptible bacterial infections; however, its use is limited due to its administration as an injection only with poor patient compliance. Since oral drug administration encourage high patient compliance with resultant effect in improved therapy, cefepime was formulated as solid lipid microparticles for oral delivery using the concept of solidified micellar carrier system. The carrier system was evaluated based on particle yield, particle size and morphology, encapsulation efficiency (EE %), and thermal analysis using differential scanning calorimeter (DSC). Preliminary microbiological studies were done using gram positive and negative bacteria. In vitro release study was performed using biorelevant media, while in vivo release study was performed in white albino rats. The yield of solid lipid microparticles (SLM) ranged from 84.2 – 98.0 %. The SLM were spherical with size ranges of 3.8 ± 1.2 to 42.0 ± 1.4 µm. The EE % calculated ranged from 83.6 – 94.8 %. Thermal analysis showed that SLM was less crystalline with high potential for drug entrapment. Microbial studies showed that cefepime retained its broad spectrum anti-bacterial activity. In vitro release showed sustained release of cefepime from SLM, and in vivo release study showed high concentration of cefepime released in the plasma of study rats. The study showed that smart engineering of solidified micellar carrier system could be used to improve oral delivery of cefepime.

Formulation and Evaluation of Itopride Hydrochloride Floating Beads for Gastroretentive Delivery

2013 ◽  
Vol 6 (4) ◽  
pp. 2269-2280
Author(s):  
Nagratna Dhople ◽  
P N Dandag ◽  
A P Gadad ◽  
C K Pandey ◽  
Masthiholimath V S
Keyword(s):  
Sustained Release ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Sustained Release Formulation ◽  
Prokinetic Drug ◽  
Drug Entrapment Efficiency ◽  
Itopride Hydrochloride ◽  
Vitro Release

A gastroretentive sustained release system of itopride hydrochloride was formulated to increase the gastric residence time and modulate its release behavior. Itopride hydrochloride is a prokinetic drug used in the treatment of gastroeosophageal reflux disease, Non-ulcer dyspepsia and as an antiemetic. Hence, itopride hydrochloride beads were prepared by emulsion gelation method by employing low methoxy pectin and sodium alginate as sustained release polymers in three different ratios alone and in combination and sunflower oil was used to enable floating property to the beads. The effect of variation in polymer and their concentration was investigated. The beads were evaluated for production yield, particle size, swelling index, density measurement, buoyancy, drug content, drug entrapment efficiency, in vitro release characteristics and release kinetic study. Based on drug entrapment efficiency, buoyancy, swelling and in vitro release, F9 was selected as the optimized formulation. F9 was further subjected to surface morphology by SEM, in vitro release comparison with marketed formulation, in vivo floating study in rabbits and stability study for 90 days. In vitro release follows zero order and fitted in Korsmeyer peppas model (Non-Fickian release). Therefore, the rate of drug release is due to the combined effect of drug diffusion and polymer swelling. The in vivo X-ray studies revealed that the beads were floating in the rabbit stomach up to 10 hours. Thus, it was concluded that the sustained release formulation containing itopride hydrochloride was found to improve patient compliance, minimize the side effects and decrease the frequency of administration.

Medicament Release from Ointment Bases: III. Ibuprofen: In Vitro Release and In-Vivo Absorption in Rabbits

1986 ◽  
Vol 12 (14) ◽  
pp. 2521-2540 ◽  
Author(s):  
A. Muktadir ◽  
A. Babar ◽  
A. J. Cutie ◽  
F. M. Plakogiannis
Keyword(s):  
In Vitro Release ◽  
In Vivo Absorption ◽  
Vitro Release

Preparation, Characterization and In Vitro Release Kinetics of Vancomycin Carried β-TCP/Chitosan Composite Microspheres Used as Bone Tissue Engineering Scaffolds

2012 ◽  
Vol 512-515 ◽  
pp. 1821-1825
Author(s):  
Lin Zhang ◽  
Xue Min Cui ◽  
Qing Feng Zan ◽  
Li Min Dong ◽  
Chen Wang ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Release Kinetics ◽  
In Vitro Release ◽  
Cross Linking ◽  
Tissue Engineering Scaffolds ◽  
Composite Microspheres ◽  
Chitosan Composite ◽  
Vitro Release

A novel microsphere scaffolds composed of chitosan and β-TCP containing vancomycin was designed and prepared. The β-TCP/chitosan composite microspheres were prepared by solid-in-water-in-oil (s/w/o) emulsion cross-linking method with or without pre-cross-linking process. The mode of vancomycin maintaining in the β-TCP/chitosan composite microspheres was detected by Fourier transform infrared spectroscopy (FTIR). The in vitro release curve of vancomycin in simulated body fluid (SBF) was estimated. The results revealed that the pre-cross-linking prepared microspheres possessed higher loading efficiency (LE) and encapsulation efficiency (EE) especially decreasing the previous burst mass of vancomycin in incipient release. These composite microspheres got excellent sphere and well surface roughness in morphology. Vancomycin was encapsulated in composite microspheres through absorption and cross-linking. While in-vitro release curves illustrated that vancomycin release depond on diffusing firstly and then on the degradation ratio later. The microspheres loading with vancomycin would be to restore bone defect, meanwhile to inhibit bacterium proliferation. These bioactive, degradable composite microspheres have potential applications in 3D tissue engineering of bone and other tissues in vitro and in vivo.

Sign in / Sign up

Export Citation Format

Share Document