Search results for "030226 pharmacology & pharmacy"

A UHPLC-UV Method to Quantify Skin Deposition and Transdermal Permeation of Tizanidine Hydrochloride

2015

Tizanidine hydrochloride is an α2-adrenergic agonist used for the symptomatic relief of spasticity associated with multiple sclerosis or with spinal cord injury or disease. The objective of this study was to develop an isocratic, robust and sensitive ultra-high performance liquid chromatography method using UV detection for use in a project to develop a transdermal therapeutic system to deliver tizanidine across the skin. Isocratic separation was achieved using a C18 column and a mobile phase comprising a 80:20 mixture of 0.004% trifluoroacetic acid in water and MeCN (pH* 3.2) at a flow rate of 0.2 mL min(-1) Tizanidine eluted at 1.499 min and the total run time was 2 min. The method was sp…

Metabolic detoxification: implications for thresholds.

2000

The fact that chemical carcinogenesis involves single, isolated, essentially irreversible molecular events as discrete steps, several of which must occur in a row to finally culminate in the development of a malignancy, rather suggests that an absolute threshold for chemical carcinogens may not exist. However, practical thresholds may exist due to saturable pathways involved in the metabolic processing, especially in the metabolic inactivation, of such compounds. An important example for such a pathway is the enzymatic hydrolysis of epoxides via epoxide hydrolases, a group of enzymes for which the catalytic mechanism has recently been established. These enzymes convert their substrates via…

Resistance to water and abrasion of a broad-spectrum sunscreen: a prospective, open-label study.

2015

Web searches for anxiolytic drugs during the COVID-19 outbreak in the USA

2021

Several lines of evidence attest that the ongoing coronavirus disease 2019 (COVID-19) pandemic is accompanied by a vast array of physiological problems in the community.1 Since the emergence or magnification of anxiety disorders in the general population has also been suggested during the COVID-19 outbreak,2 we aimed to provide further insights on this matter by performing an electronic search in Google Trends (Google Inc, Mountain View, CA, USA), using the terms corresponding to the most common anxiolytic medicines used in the USA (ie, ‘Alprazolam’, ‘Diazepam’, ‘Lorazepam’, and ‘Clonazepam’) along with their brand names (‘Xanax’, ‘Valium’, ‘Ativan’, and ‘Klonopin’, respectively), and setti…

The European COVID-19 drugs calculation tool: an aid for the estimation of the drugs needed during the SARS-CoV 2 pandemic

2021

Objective To create an informatics supportive tool, which can assist healthcare professionals in estimating potential requirements for essential drug supplies to respond to the current SARS-CoV-2 pandemic based on epidemiological forecasting. Methods The tool was based on a Susceptible-Infected-Removed (SIR) epidemiological model in which the population is divided into three compartments and transmission parameters are specified to define the rate at which people move between stages. Appropriate data entry was guaranteed by the creation of structured guided paths. The drugs needed for the forecasted patients were estimated according to a list of critical care drugs compiled by consulting pr…

Salmeterol Xinafoate (SX) loaded into mucoadhesive solid lipid microparticles for COPD treatment

2019

Chronic obstructive pulmonary disease (COPD) is one of the main health problems worldwide. It is characterised by chronic inflammation in the lungs that leads to progressive, chronic, largely irreversible airflow obstruction. The use of long-acting β agonists remain today the frontline treatment for COPD with the aim of minimizing side effects and enhancing therapeutic usefulness. To this purpose, in this paper, mucoadhesive solid lipid microparticles (SLMs) containing a long-acting β-2 agonist, Salmeterol Xinafoate (SX) were prepared, characterised (size, z-potential, aerodynamic diameter, turbidimetric evaluations, drug loading and entrapping efficiency) and tested in a model of bronchial…

Glycerosomes: Use of hydrogenated soy phosphatidylcholine mixture and its effect on vesicle features and diclofenac skin penetration.

2016

In this work, diclofenac was encapsulated, as sodium salt, in glycerosomes containing 10, 20 or 30% of glycerol in the water phase with the aim to ameliorate its topical efficacy. Taking into account previous findings, glycerosome formulation was modified, in terms of economic suitability, using a cheap and commercially available mixture of hydrogenated soy phosphatidylcholine (P90H). P90H glycerosomes were spherical and multilamellar; photon correlation spectroscopy showed that obtained vesicles were ∼131nm, slightly larger and more polydispersed than those made with dipalmitoylphosphatidylcholine (DPPC) but, surprisingly, they were able to ameliorate the local delivery of diclofenac, whic…

Solid microcrystalline dispersion films as a new strategy to improve the dissolution rate of poorly water soluble drugs: A case study using olanzapine

2016

In this study, we evaluate the dissolution rate enhancement of solid microcrystalline dispersion (SMD) films of olanzapine (OLZ) formulated with four water-soluble polymers namely poly(N-vinylpyrrolidone) (PVP), poloxamer 188 (P188), poloxamer 407 (P407) and Soluplus(®) (SLP). Prepared formulations were characterised to determine particle size, morphology, hydrogen bonding interactions, thermal characteristics as well as in vitro dissolution studies conducted under sink conditions (pH 6.8). Particle size of OLZ in all formulations ranged between 42 and 58μm. Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR), Differential Scanning Calorimetry (DSC) and Hot-Stage…

Cubic Microcontainers Improve In Situ Colonic Mucoadhesion and Absorption of Amoxicillin in Rats

2020

An increased interest in colonic drug delivery has led to a higher focus on the design of delivery devices targeting this part of the gastrointestinal tract. Microcontainers have previously facilitated an increase in oral bioavailability of drugs. The surface texture and shape of microcontainers have proven to influence the mucoadhesion ex vivo. In the present work, these findings were further investigated using an in situ closed-loop perfusion technique in the rat colon, which allowed for simultaneous evaluation of mucoadhesion of the microcontainers as well as drug absorption. Cylindrical, triangular and cubic microcontainers, with the same exterior surface area, were evaluated based on i…

Quantitative analysis of the effect of controlled-release formulation on nonlinear gastrointestinal absorption of P-glycoprotein substrate talinolol …

2020

Abstract Oral absorption of talinolol, a substrate of P-glycoprotein (P-gp), from a sustained-release (SR) formulation was reportedly decreased compared to that from an immediate-release (IR) formulation. The aim of this study was to predict and understand the effect of controlled-release formulation on the oral absorption of P-gp substrates by developing a physiologically based pharmacokinetic (PBPK) absorption model incorporating multiple kinetic parameters obtained from in vitro studies, using talinolol as a model substrate. Simulation analysis using the developed PBPK absorption model indicated that the clinically observed marked decrease in the plasma concentration of talinolol adminis…