Effect of protein kinase C inhibitors and activators on corneal re-epithelialization in the rat

PURPOSE: To examine the ability of protein kinase C (PKC) inhibitors and activators to influence the rate of corneal re-epithelialization in the rat. METHOD: Rat corneas with 3 mm diameter central epithelial abrasions were organ-cultured in control medium or in medium with inhibitors or activators of PKC. RESULTS: In control corneas, the defect was completely re-epithelialized by 25 hr. In the presence of the PKC inhibitors staurosporine (100 nM), sphinganine (50 mumol/l), or H-7 (100 mumol/l) there were significantly larger epithelial defects than in controls after 5-25 hr of incubation. Re-epithelialization rates were similar to control corneas when the incubation medium contained HA1004 (100 mumol/l), an analogue of H-7 that is a potent inhibitor of cyclic adenosine monophosphate- and cyclic guanosine monophosphate-dependent protein kinases and a weak inhibitor of PKC. Two PKC activators, 1-oleoyl-2-acetyl-sn-glycerol (OAG) and phorbol 12-myristate 13-acetate (PMA), were unable to enhance the rate of epithelial wound healing. CONCLUSIONS: Our results suggest that PKC activity is an important factor in regulating corneal epithelial wound healing, presumably by influencing cell migration. Moreover, the results with OAG and PMA suggest that PKC is maximally activated during re-epithelialization in this organ-culture assay

Plasma membrane redox system in the erythrocytes of rowers: Pilot study

The oxidative stress results from a change in the physiological balance between oxidant and antioxidant species. This type of stress is a chemical change in the redox state of cells. The increased production of reactive species is related to an excessive metabolic activation, for example, from an intense physical exercise or an excessive caloric intake (1). In physiological conditions, muscle fibers are provided with an antioxidant system able to keep under control the excessive production of Reactive Oxygen Species (ROS)

Effects of Rapid Weight Loss on Kidney Function in Combat Sport Athletes

Even though scientific literature shows numerous heath complications and performance decrements associated with rapid weight loss (RWL), its prevalence remains exceedingly high across various combat sports. The aim of this study was to thoroughly search the existing literature to explore the influence of RWL on kidney function in Olympic and non-Olympic combat sport athletes. PubMed and Web of Science were searched for the relevant studies. Only original articles published from 2005 onwards, written in English, that included healthy males and females who prompted ~5% weight loss within a week or less, were included in the study. Retrieved studies showed that creatinine, blood urea nitrogen and urine specific gravity values were significantly increased after RWL in the majority of the included studies. This observation indicates that RWL caused dehydration and subsequent acute kidney damage despite various degrees of weight lost during the RWL phase, which can lead to adverse events in other body systems. Alternative methods of weight reduction that prioritize athletes’ health should be considered

Effective strategies for promoting physical activity through the use of digital media among school-age children: A systematic review

Digital media are widespread among school-age children, and their incorrect use may lead to an increase in sedentary levels and the consequences associated with it. There are still few studies that have investigated whether physical activity levels could be increased through their use. The aim of this study was to systematically review the scientific literature in order to identify whether digital strategies and technologies are capable of increasing the level of physical activity. A literature search was performed using the following databases: Pubmed, Scopus, and Web of Science. The main outcomes evaluated the increase in physical activity levels, the number of steps, and the reduction of sedentary behaviors. Two trained researchers independently assessed eligible studies against eligibility criteria, extracted data, and assessed the risk of bias. The Downs and Black checklist was used to assess the quality of the included studies. A total of 15 studies (1122 children) were included in this systematic review, with a mean age of 8.45 ± 0.70 years. Quality assessment of the studies observed a “moderate quality” of the included records. The results of this systematic review highlight that digital media can be applied as a way to improve the levels of physical activity in children to contrast a sedentary lifestyle. The main limitations of the study are the heterogeneity within the exercise protocols and the paucity of studies involving school-age children. More research is needed to confirm our findings also due to continuing technological progress