Search results for "delivery"

Designing Medical Devices Based on Silicon Polymeric Material with Controlled Release of Local Anesthetics

2012

The drug delivery systems that are the object of this article take the form of a polymer matrix made of silicone containing a drug. These devices can be used as patches for local dermal applications releasing the drug in a controlled manner. The model active agent, lidocaine hydrochloride was chosen from the range of local anesthetics. When the drug is restricted to the surface, it is released more rapidly than when it is allowed to spread evenly throughout the silicon structure. When hydrophilic polymers such as PVA and HEC are mixed in with the lidocaine hydrochloride and deposited on the surface of the polymer matrix, we observed that the burst effect was eliminated without modifying the…

New copolymers graft of α,β-poly(N-2-hydroxyethyl)-d,l-aspartamide obtained from atom transfer radical polymerization as vector for gene delivery

2012

Abstract New cationic α,β-poly(N-2-hydroxyethyl)- d , l -aspartamide (PHEA) graft copolymers were synthesized by ATRP, using diethylamino ethyl methacrylate (DEAEMA) as monomer for polymerization, yielding polycations (PHEA-pDEAEMA) able to condense DNA. Then, consecutive ATRP conditions were set up on PHEA-pDEAEMA to obtain copolymers containing also hydrophilic chains (PHEA-IB-pDMAEMA-pPEGMA) able to improve biocompatibility of polyplexes and to provide them stealth properties. Agarose gel studies showed that the copolymers effectively condensed plasmid DNA to form polyplexes. Light scattering studies were used to analyze the size and the ζ -potential of these polyplexes, showing that cop…

New methods of delivery of amphotericin B.

1993

Fungal infections continue to be a major problem in the management of immunocompromised patients. Despite its formidable toxicity and treatment failures, amphotericin B is still the drug of choice for most of these infections. One strategy for reducing the toxicity of amphotericin B and thus permitting administration of higher doses is that of using less toxic formulations. Entrapping amphotericin B into liposomes or binding it to other substances reduces its toxicity to host cells, whereas the selective binding of amphotericin B to ergosterol preserves its toxicity to fungal cells. Adding fungus-specific antibodies to such liposomes may further increase the efficiency of drug targeting. Th…

The International Guideline Evaluation Screening Tool (IGEST): development and validation.

2022

Abstract Background Guideline adaptation provides an important alternative to de novo guideline development by making the process more efficient and reducing unnecessary duplication. The quality evaluation of international guidelines is an essential part of the adaptation process. The study aims at describing the development and validation of a new tool to screen trustworthy Clinical Practice Guidelines (CPGs) for their adoption/adaption: the International Guideline Evaluation Screening Tool (IGEST). Methods The process of developing the IGEST involved two main phases: 1) tool development and 2) content validation. The tool development phase comprised three stages, where the scope of the IG…

In Defense of Sympathy, in Consideration of Empathy, and in Praise of Compassion: A History of the Present.

2017

Micro- to Nanoscale Bio-Hybrid Hydrogels Engineered by Ionizing Radiation

2021

Bio-hybrid hydrogels consist of a water-swollen hydrophilic polymer network encapsulating or conjugating single biomolecules, or larger and more complex biological constructs like whole cells. By modulating at least one dimension of the hydrogel system at the micro- or nanoscale, the activity of the biological component can be extremely upgraded with clear advantages for the development of therapeutic or diagnostic micro- and nano-devices. Gamma or e-beam irradiation of polymers allow a good control of the chemistry at the micro-/nanoscale with minimal recourse to toxic reactants and solvents. Another potential advantage is to obtain simultaneous sterilization when the absorbed doses are wi…

Can sucrose content in the phloem sap reaching field pea seeds (Pisum sativum L.) be an accurate indicator of seed growth potential ?

2003

The composition of the translocates reaching the seeds of pea plants having various nitrogen (N) nutrition regimes was investigated under field situations. Sucrose flow in the phloem sap increased with the node number, but was not significantly different between N nutrition levels. Because N deficiency reduced the number of flowering nodes and the number of seeds per pod, the sucrose flow bleeding from cut peduncles was divided by the number of seeds to give the amount of assimilates available per seed. The sucrose concentration in phloem sap supplied to seeds at the upper nodes was higher than that at the lower nodes. The flow of sucrose delivered to the seeds during the cell division peri…

Capacity assessment for provision of quality sexual reproductive health and HIV-integrated services in Karamoja, Uganda

2020

Introduction: Sexual and reproductive health (SRH) and Human Immunodeficiency Virus (HIV) are crucial global health issues. Uganda continues to sustain a huge burden of HIV and AIDS.
 Methods: A cross-sectional health facility-based assessment was performed in November and December 2016 in Karamoja Region, northern Uganda. All the 126 health facilities (HFs) in Karamoja, including 5 hospitals and 121 Health Centers (HCs), covering 51 sub-counties of the 7 districts were assessed. We assessed the capacity of a) leadership and governance, b) human resource, c) service delivery, d) SRH and HIV service integration and e) users satisfaction and perceptions.
 Results: 64% of the establi…

Self-assembled PAA-based nanoparticles as potential gene and protein delivery systems

2012

A series of nanoparticles is prepared via layer-by-layer assembly of oppositely charged, synthetic biocompatible polyamidoamine polymers as potential carriers. Particle size, surface charge and internal chain mobility are quantified as a function of the polymer type and number of layers. The effect of addition of surfactant is examined to simulate the effects of nanoparticle dissolution. The cyctotoxicity of these particles (in epithelia and murine cell lines) are orders of magnitude lower than polyethyleneimine controls. Stable nanoparticles may be prepared from mixtures of strongly, oppositely charged polymers, but less successfully from weakly charged polymers, and, given their acceptabl…

The Health Risks of Electronic Cigarettes Use in Adolescents

2020

The evidence to date suggests that vaping is not a safe alternative to smoking tobacco. This, coupled with the worrying trend of young nonsmokers being attracted to vaping, raises fears of yet another generation suffering from chronic lung disease and other acute and chronic health conditions. Finally, due to the insufficient regulations in several countries, up-to-date data on the prevalence of e-cigarette use and studies on the health's implications of their use are urgently needed to inform policy at a national and international level (ie, European Union). Pediatricians are typically on the front line for identifying emerging risks for children and adolescents ; therefore, they may effec…