Controlled release of naringenin from soft hydrogel contact lens: An investigation into lens critical properties and in vitro release.

The naringenin (NAR)-impregnated hydrogel lenses (nesofilcon A material) were manufactured in this study with the feasibility to achieve controlled daily drug release. The lenses were fabricated using a comparable commercial-standard process, utilizing injection molding and thermal curing approaches. NAR-loaded lenses were prepared by both direct entrapment and 'soak and release' methods. Their critical properties were tested to ISO standards and comparable to the commercial lenses. NAR was fully characterized by studying its physical and chemical stability throughout the manufacturing processes using thermal analysis, high performance liquid chromatography and X-ray diffraction analysis. The NAR-loaded lenses showed > 97% light transmission, >75% water content, 0.50-0.53 ± 0.06 MPa tensile strength, with a lens diameter of 14.1 ± 0.1 mm. Lens polymerization kinetics were studied using differential scanning calorimetry. NAR released from the lens, prepared by a direct entrapment approach, followed a diffusion-controlled mechanism, and provided a controlled drug release of 72-82% for 24 h. A faster release rate was observed for NAR-loaded lenses prepared by a soak and release method, with over 90% of NAR was releasedin the first five hours.

Pharmaceutical-loaded contact lenses as an ocular drug delivery system: A review of critical lens characterization methodologies with reference to ISO standards.

Therapeutic contact lenses for ocular drug delivery have received considerable interest as they can potentially enhance ocular bioavailability, increase patient compliance, and reduce side effects. Along with the successful in vitro and in vivo studies on sustained drug delivery through contact lenses, lens critical properties such as water content, optical transparency and modulus have also been investigated. Aside from issues such as drug stability or burst release, the potential for the commercialization of pharmaceutical-loaded lenses can be limited by the alteration of lens physical and chemical properties upon the incorporation of therapeutic or non-therapeutic components. This review outlines advances in the use of pharmaceutical-loaded contact lenses and their relevant characterization methodologies as a potential ocular drug delivery system from 2010 to 2020, while summarizing current gaps and challenges in this field. A key reference point for this review is the relevant ISO standards on contact lenses, relating to the associated characterization methodologies. The content of this review is categorized based on the chemical, physical and mechanical properties of the loaded lens with the shortcomings of such analytical technologies examined.

Cannabidiol reduces withdrawal symptoms in nicotine-dependent rats.

RATIONALE: Cannabidiol (CBD) reduces craving in animal models of alcohol and cocaine use and is known to modulate nicotinic receptor function, suggesting that it may alleviate symptoms of nicotine withdrawal. However, preclinical evaluation of its efficacy is still lacking. OBJECTIVES: The goal of this study was to test the preclinical efficacy of a chronic CBD treatment in reducing nicotine dependence using measures of withdrawal symptoms including somatic signs, hyperalgesia, and weight gain during acute and protracted abstinence. METHODS: Male and female Wistar rats were made dependent on nicotine using osmotic minipumps (3.15 mg/kg/day) for 2 weeks, after which minipumps were removed to induce spontaneous withdrawal. Three groups received CBD injections at doses of 7.5, 15, and 30 mg/kg/day for 2 weeks, starting 1 week into chronic nicotine infusion. The control groups included rats with nicotine minipumps that received vehicle injections of sesame oil instead of CBD; rats implanted with saline minipumps received sesame oil injections (double vehicle) or the highest dose of CBD 30 mg/kg/day. Throughout the experiment, serum was collected for determination of CBD and nicotine concentrations, mechanical sensitivity threshold and withdrawal scores were measured, and body weight was recorded. RESULTS: CBD prevented rats from exhibiting somatic signs of withdrawal and hyperalgesia during acute and protracted abstinence. There was no dose-response observed for CBD, suggesting a ceiling effect at the doses used and the potential for lower effective doses of CBD. The saline minipump group did not show either somatic signs of withdrawal or hyperalgesia during acute and protracted abstinence, and the highest dose of CBD used (30 mg/kg/day) did not alter these results. CONCLUSIONS: This preclinical study suggests that using CBD as a strategy to alleviate the withdrawal symptoms upon nicotine cessation may be beneficial.

Undergraduate Participation in the Society for Neuroscience.

Undergraduate neuroscience education has grown substantially in the US as well as participation in outreach and research activities by undergraduates. In line with these observations, undergraduates may also be seeking membership in the Society for Neuroscience (SfN) as well as attending the SfN annual meeting. Data in the present report show that undergraduate membership in SfN has increased between 2013 and 2019 as well as annual undergraduate SfN meeting attendance and abstract submissions for research presentations. Increases were observed for both US and international undergraduates. These data are discussed in the context of motivations of undergraduates to pursue future academic training and/or careers in neuroscience. These data are important to faculty and administrators at institutions that currently have or seek to establish new undergraduate neuroscience programs given membership in a professional society and attendance at a major conference can positively impact academic and professional development.