Search results for "Lease"
showing 10 items of 886 documents
In VitroRelease of Local Anaesthetic and Anti-Inflammatory Drugs from Crosslinked Collagen Based Device
2012
The drug delivery systems that are the object of this article take the form of a hydrophilic matrix (collagen or crosslinked collagen) containing a drug. These devices can be used as The model active agents, were chosen from the range of local anaesthetics (lidocaine hydrochloride), anti-inflammatory (diclofenac sodium salt) and antioxydant (caffeic acid). Whatever the drug affinity for water, in the first time of the experiments, the release appears to be systematically delayed when the matrix is crosslinked. For lidocaine hydrochloride based systems, as the amount of drug increases in the matrix, the high gap concentration between the matrix and the buffer solution promote the diffusion a…
Polymer-based systems for controlled release and targeting of drugs
2019
The current need to find new advanced approaches to carry biologically active substances (conventional organic drugs, peptides, proteins (such as antibodies), and nucleic acid-based drugs (NABDs such as siRNA and miRNA)) in the body fluids, to realize targeted therapies and even personalized ones, goes hand in hand with research on the performance of new materials to better realize appropriate drug vectors [...]
Calixarene: A Versatile Material for Drug Design and Applications
2016
The therapy of various diseases by the drugs entrapped in calixarene derivatives is gaining attraction of researchers nowadays. Calixarenes are macrocyclic nano-baskets which belong to cavitands class of host-guest chemistry. They are the marvelous hosts with distinct hydrophobic three dimensional cavities to entrap and encapsulate biologically active guest drugs. Calixarene and its derivatives develop inclusion complexes with various types of drugs and vitamins for their sustained/targeted release. Calixarene and its derivatives are used as carriers for anti-cancer, anti-convulsant, anti-hypertensive, anthelmentic, anti-inflammatory, antimicrobial and antipsychotic drugs. They are the impo…
Ion-pair approach coupled with nanoparticle formation to increase bioavailability of a low permeability charged drug.
2018
Abstract Atenolol is a drug widely used for the treatment of hypertension. However, the great drawback it presents is a low bioavailability after oral administration. To obtain formulations that allow to improve the bioavailability of this drug is a challenge for the pharmaceutical technology. The objective of this work was to increase the rate and extent of intestinal absorption of atenolol as model of a low permeability drug, developing a double technology strategy. To increase atenolol permeability an ion pair with brilliant blue was designed and the sustained release achieved through encapsulation in polymeric nanoparticles (NPs). The in vitro release studies showed a pH-dependent relea…
Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Carbamazepine.
2020
Abstract Literature relevant to assessing whether BCS-based biowaivers can be applied to immediate release (IR) solid oral dosage forms containing carbamazepine as the single active pharmaceutical ingredient are reviewed. Carbamazepine, which is used for the prophylactic therapy of epilepsy, is a non-ionizable drug that cannot be considered “highly soluble” across the range of pH values usually encountered in the upper gastrointestinal tract. Furthermore, evidence in the open literature suggests that carbamazepine is a BCS Class 2 drug. Nevertheless, the oral absolute bioavailability of carbamazepine lies between 70 and 78% and both in vivo and in vitro data support the classification of ca…
The 2-5A System and HIV Infection
1994
The human immunodeficiency virus type 1 (HIV-1) is the etiologic agent of acquired immunodeficiency syndrome (AIDS). The progression of this retro viral disease is associated with various clinical manifestations, including the acquisition of an immunodeficient state, the frequent presence of neurological disorders, and some malignancies (reviewed in Barre-Sinoussi et al. 1983; Wong-Staal and Gallo 1985; Fauci 1988). Immunologic dysfunctions caused by HIV-1 infection include disorders in the production of cytokines (Murray et al. 1984; Abb et al. 1986). For example, a significant decrease in the production of interferon-α (IFN-α) by cultured peripheral blood mononuclear cells (PBMC) from pat…
Geographic variability of ecological niches of plant species: are competition and stress relevant?
2002
A species’ niche position may differ strongly between geographic regions, for instance due to the effect of competitors or ecophysiological stress. However, it is unclear whether such strong geographic niche variation is the rule or the exception. We compared the niche positions of plant species between central England and eastern central Europe (as available from the literature), using phylogenetically independent contrasts. We found that most species occupied similar niche positions in both regions. More importantly, we found that niche variation was not higher in species susceptible to competitive displacement. Nor was niche variation higher in species that reach the edge of their range …
Externalities and article citations: experience of a national public health journal (Gaceta Sanitaria)
2016
Purpose: The purpose of the study was to analyze the determinants of citations such as publication year, article type, article topic, article selected for a press release, number of articles previously published by the corresponding author, and publication language in a Spanish journal of public health. Methods: Observational study including all articles published in Gaceta Sanitaria during 2007-2011. We retrieved the number of citations from the ISI Web of Knowledge database in June 2013 and also information on other variables such as number of articles published by the corresponding author in the previous 5 years (searched through PubMed), selection for a press release, publication langua…
Sliding-end-labelling
1986
Abstract A method, termed ‘sliding-end-labelling’, has been devised to avoid a frequent artifact in nucleosome positioning by indirect end labelling, namely the appearing of DNA fragments originated by two nuclease cuts, one of them lying within the region covered by the probe. The method is applied to the nucleosome positioning in the yeast SUC2 gene for invertase.
Stability of PEI–DNA and DOTAP–DNA complexes: effect of alkaline pH, heparin and serum
2001
Abstract DNA complexes formed with nonviral vectors such as polyethylenimine (PEI) or 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) are widely used in gene therapy. These complexes prevent the interaction of DNA with the fluorescent probes usually employed to quantify DNA. We thus studied the procedures for DNA quantification from DNA complexes as well as their stability in the presence of DNase or mouse, rat and human sera. Release of the DNA from its complexes was accomplished by increasing the pH of the medium (from 7.3 to 13.4) or by adding heparin. The stability against degradation was tested in vitro, by incubating the complexes at 37°C in the presence of DNase I and sera from the …