Potassium ion influx and Na+,K+-ATPase activity are required for the hamster sperm acrosome reaction.

The role of a K+ ion influx and Na+,K+-ATPase activity in the hamster sperm acrosome reaction (AR) was examined, using a range of concentrations of K+,K+ ionophores and a Na+,K+-ATPase inhibitor. Washed epididymal hamster sperm, capacitated in vitro in an artificial medium containing 2 mM Ca2+, 147 mM Na+, and 3, 6, 12, 18, or 24 mM K+, began undergoing the AR after 3 h of incubation. Sperm incubated in low K+ (0.9 mM) failed to undergo the AR even after 5 h of incubation. Sperm in 0.9 mM K+ could be induced to undergo the AR when either K+ (12 mM) alone or K+ (12 mM) with 0.1 microM nigericin was added after 3.5 h of incubation. The addition of K+ alone stimulated the AR in 30 min, whereas nigericin plus K+ stimulated the AR 15 min after addition. Neither nigericin added alone (0.9 mM K+) nor nigericin plus 12 mM K+ added to a low Ca2+ (0.35 mM) system resulted in acrosome reactions. Valinomycin (1 nM) did not stimulate the AR when added together with K+ (3-24 mM) to sperm incubated in 0.9 mM K+ for 3.5 h but markedly decreased sperm motility. Micromolar levels of ouabain blocked the AR when added between t = 0--3 h to sperm incubated with 3-24 mM K+. Inhibition of AR by the addition of 1 microM ouabain to sperm incubated with 3 mM K+ was completely reversed by the addition of 0.1 microM nigericin at t = 3.5 h. These results suggest that Na+,K+-ATPase activity and the resulting K+ influx are important for the mammalian sperm AR. Some similarities between requirements for the hamster sperm AR and secretory granule exocytosis are discussed

Improving the outcomes of biopharmaceutical delivery via the subcutaneous route by understanding the chemical, physical and physiological properties of the subcutaneous injection site

Subcutaneous (SC) injection is currently the most common route of self-administering biopharmaceuticals such as proteins and peptides. While pharmaceutical scientists have acquired great skill in identifying formulations for these proteins and peptides with multi-year shelf life stability, the SC injection of these formulations can result in inconsistent or particularly low bioavailability outcomes. We hypothesise that upon injection, the chemical, physical and physiological properties of the subcutaneous tissue may play a crucial role in determining the therapeutic outcomes of SC injected biopharmaceuticals. We contend that physical and chemical stresses placed upon the injected protein or peptide as it transitions from the non-physiological environment of its formulation to the homeostatic conditions of the SC tissue can affect its fate following injection, and that by taking this environment into account when formulating, more precisely controlled release of SC injected biopharmaceuticals could be achieved. In this mini-review we describe how events that occur to an injected protein or peptide during this post-injection transition period could affect the diffusion of bioactive material to blood capillaries and lymphatic vessels. With this in mind, we have reviewed the chemical, physical and physiological attributes of the SC tissue and collated studies on how these properties are known to affect protein stability and diffusional properties. Finally, examples where the understanding of the properties of the SC tissue when formulating for SC injected biopharmaceuticals has improved the predictability of drug delivery via the SC route are discussed, with the need for novel tools for rational and informed formulation development highlighted

Sleep as an Occupation in College Students

The purpose of this study was to measure the quality of sleep in undergraduate college students and explore the relationship between academic self-efficacy and performance in student-related occupations. A quantitative, exploratory, descriptive and correlational research design was used to explore the relationship among sleep quality, perceived self-efficacy, and selected student characteristics. This study included undergraduate students, as well as self-identified student athletes, first generation students, and students with disabilities. To collect data, the researchers conducted an online survey, which consisted of the Pittsburgh Sleep Quality Index (PSQI), a demographic and self-efficacy questionnaire. The PSQI was used to evaluate the sleep quality, while the demographic and self-efficacy questionnaire gathered information about student related occupations and self-efficacy. Two hundred and nine college students, aged 17 to 25, participated in the survey. One hundred thirty five (64.6%) participants scored above a five, indicating poor sleep quality while 74 (35.4%) participants obtained good sleep quality as measured by the PSQI, while. The average number of hours slept reported by participants was 6.68. Results support existing evidence suggesting college students are sleep deprived, and over half of participants reported sleep issues that could be addressed by an occupational therapist.https://scholar.dominican.edu/ug-student-posters/1013/thumbnail.jp

Does therapeutic horseback riding decrease balance deficits in community-dwelling older adults?

Hippotherapy and therapeutic riding (TR) provide pleasurable activity and physical exercise to individuals and yet limited study is available on its therapeutic value to improve balance in older adults. In this study, the researchers measured the benefit of TR on balance and quality of life in communitydwelling older adults. A convenience sample of individuals 65 years and older was recruited from a local community. The study is a single-blind, pretest-posttest, controlled study of a 10-session TR program with a Professional Association of Therapeutic Horsemanship (PATH) trained and certified TR instructor. Each TR session included grooming and tacking, mounting, a warm-up exercise on the horse, riding, and dismounting. The results of this study showed a significant improvement in balance scores as well as participant perception of overall health after the intervention period. Therefore, this study illustrated the practicality, safety, and benefit on improvement of balance in community-dwelling older adults from a short-term TR program. However, the small sample size prevented the data from being conclusive. Larger scale studies should be conducted to clinically prove the benefit of therapeutic riding for older adults. Therapeutic riding has the potential to improve balance and increase quality of life in older adults. Connecting the results from this study to the larger issue of fall prevention may provide evidence to include hippotherapy or TR in occupational therapy for older adults with balance deficits

Unsaturated glycoceramides as molecular carriers for mucosal drug delivery of GLP-1

The incretin hormone Glucagon-like peptide 1 (GLP-1) requires delivery by injection for the treatment of Type 2 diabetes mellitus. Here, we test if the properties of glycosphingolipid trafficking in epithelial cells can be applied to convert GLP-1 into a molecule suitable for mucosal absorption. GLP-1 was coupled to the extracellular oligosaccharide domain of GM1 species containing ceramides with different fatty acids and with minimal loss of incretin bioactivity. When applied to apical surfaces of polarized epithelial cells in monolayer culture, only GLP-1 coupled to GM1-ceramides with short- or cis-unsaturated fatty acids trafficked efficiently across the cell to the basolateral membrane by transcytosis. In vivo studies showed mucosal absorption after nasal administration. The results substantiate our recently reported dependence on ceramide structure for trafficking the GM1 across polarized epithelial cells and support the idea that specific glycosphingolipids can be harnessed as molecular vehicles for mucosal delivery of therapeutic peptides