27 research outputs found
Protection from ultraviolet damage and photocarcinogenesis by vitamin d compounds
© Springer Nature Switzerland AG 2020. Exposure of skin cells to UV radiation results in DNA damage, which if inadequately repaired, may cause mutations. UV-induced DNA damage and reactive oxygen and nitrogen species also cause local and systemic suppression of the adaptive immune system. Together, these changes underpin the development of skin tumours. The hormone derived from vitamin D, calcitriol (1,25-dihydroxyvitamin D3) and other related compounds, working via the vitamin D receptor and at least in part through endoplasmic reticulum protein 57 (ERp57), reduce cyclobutane pyrimidine dimers and oxidative DNA damage in keratinocytes and other skin cell types after UV. Calcitriol and related compounds enhance DNA repair in keratinocytes, in part through decreased reactive oxygen species, increased p53 expression and/or activation, increased repair proteins and increased energy availability in the cell when calcitriol is present after UV exposure. There is mitochondrial damage in keratinocytes after UV. In the presence of calcitriol, but not vehicle, glycolysis is increased after UV, along with increased energy-conserving autophagy and changes consistent with enhanced mitophagy. Reduced DNA damage and reduced ROS/RNS should help reduce UV-induced immune suppression. Reduced UV immune suppression is observed after topical treatment with calcitriol and related compounds in hairless mice. These protective effects of calcitriol and related compounds presumably contribute to the observed reduction in skin tumour formation in mice after chronic exposure to UV followed by topical post-irradiation treatment with calcitriol and some, though not all, related compounds
An Anthropological Approach to Education Policy as a Practice of Power: Concepts and Methods
Accepted manuscript, post print versionSince the introduction to our 2001 edited volume, Policy as Practice: Toward a Comparative Sociocultural Analysis of Education Policy (Sutton and Levinson 2001), we have continued to sketch the foundational postulates of a critical anthropological approach to the study of education policy. In 2009, we expanded and deepened many of the points from that introduction, more systematically introducing and defining theoretical terms, and providing a bit of their intellectual genealogy (Levinson et al. 2009). We also discussed certain methodological considerations that accompanied the theoretical approach, and we argued for a type of engaged educational anthropology that goes beyond the mere âstudyâ of education policy to its democratization and transformation. Here we provide an updated synopsis of our approach
Arterial compliance may be reduced by ingestion of red wine
The aim of this study was to assess the effect of alcohol on blood pressure and arterial compliance over 24âh in a group of volunteers, comparing the same group of subjects on two consecutive but separate days, one with alcohol intake (alcohol day) and one free of alcohol (control day). We studied 18 healthy subjects (mean age 34.2 years, range 25-53). The subjects received the two days in random order. On the alcohol day, the subjects were asked to drink two glasses of red wine (12% ethanol) between 1830 hours and 0430 hours. Measurements of heart rate, blood pressure and QKD interval (Q wave to Korotkoff (K) sound, diastolic phase (D) using Diasys Integra (Novacor, France)) were recorded (usually 1500 hours to 1500 hours). Three 'ingestion' periods were defined, from 1500 hours to 1830 hours ('before'), 1900 hours to 0430 hours ('during') and from 0430 hours to the following afternoon ('after') on both the alcohol day and on the control day. Red wine increased heart rate during alcohol ingestion and reduced arterial compliance after ingestion. The significant effect of interaction between day and ingestion period on heart rate, diastolic blood pressure and QKD were found, suggesting that the differences in response among the ingestion periods depended on whether alcohol has been consumed that day. For the first time our study indicates the effect of alcohol on 24âh arterial stiffness in a healthy group of volunteers.Journal of Human Hypertension advance online publication, 19 March 2015; doi:10.1038/jhh.2015.19