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Background/objectives To date, only two studies have investigated the relationship between vitamin D (vitD) deficiency and candidiasis in spite of vitD's antimicrobial and immunomodulatory roles. We examined the relationship between sunlight exposure and consumption of vitD-rich foods, markers of vitD status, and vulvovaginal candidiasis (VVC) in an African population to add to the limited evidence and stimulate additional research. Subjects/methods Three hundred cases (females diagnosed as suffering from VVC) and three hundred controls (females diagnosed as suffering from any condition other than VVC) were selected from three health facilities in Cape Coast, Ghana. Sunlight exposure was assessed in a structured questionnaire with a food frequency questionnaire used to ascertain the frequency of consumption of vitD-rich foods. Results Self-reported low sunlight exposure was associated with 3.38 (95% CI:1.99, 5.74) increased odds of VVC. Low and moderate sunlight exposure estimated by outdoor visits was also associated with increased odds of VVC. In sensitivity analysis restricted to matched sunlight exposure data, low and moderate exposure was associated with 5.78 (95% CI: 2.57, 12.99) and 3.53 (95% CI: 1.85, 6.75) increased odds of VVC. Odds of VVC increased with decreasing levels of consumption of vitD-rich foods (Likelihood-ratio test trend p = 0.1382). In the joint analysis, low and moderate vitD intake was associated with much higher increased odds of VVC. Conclusions Our findings should be confirmed in prospective studies and clinical trials to strengthen the evidence base for preventive action and to also inform clinical decision making., Author(s): A. K. Amegah [sup.1] [sup.2] , F. K. Baffour [sup.1] , A. Appiah [sup.1] , E. Adu-Frimpong [sup.1] , C. L. Wagner [sup.3] Author Affiliations: (1) Public Health Research [...]

Many semi-arid coniferous forests in western North America have reached historically unprecedented densities over the past 150 years and are dominated by shade-tolerant trees. Silvicultural treatments generally open the canopy but may not restore shade-intolerant species. We determined crossover-point irradiance (CPI) (light at which the height growth rank of pairs of species changes) for seedlings in Sierra Nevada mixed-conifer forest and used these to interpret light environments produced by fuels-reduction thinning and group selection with reserved large trees. Nine of 21 species pairs had well-defined CPIs. The CPI of the most common shade-tolerant and intolerant species (white fir (Abies concolor (Gordon & Glendl.) Lindl. ex Hildebr.) and ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson)) was 22.5 mol*[m.sup.-2] [day.sup.-1] or 41% of full sun. Median understory irradiance increased from 9.2 mol*[m.sup.-2] [day.sup.-1] (17% full sun) in pretreatment forest to 13 mol*[m.sup.-2] [day.sup.-1] (24% full sun) in lightly and 15.5 mol*[m.sup.-2] [day.sup.-1] (28% full sun) in moderately thinned stands and 37 mol*[m.sup.-2] [day.sup.-1] (67% full sun) in group-selection openings. We estimate that 5%-20% of ground area in lightly to moder-ately thinned stands would have enough light to favor shade-intolerant over shade-tolerant growth compared with 89% of ground area in group-selection openings. The CPI provides a tool to assess regeneration implications of treatment modification such as increasing heterogeneity of thinning to enhance regeneration or reserving large trees in group-selection openings to maintain wildlife habitat. Plusieurs forets resineuses semi-arides de l'ouest de l'Amerique du Nord ont atteint des densites historiquement sans precedents au cours des 150 dernieres annees et sont dominees par des especes tolerantes a l'ombre. Les traitements sylvicoles ont generalement pour effet d'ouvrir le couvert sans necessairement retablir la presence d'especes intolerantes a l'ombre. Nous avons determine le point de croisement pour l'irradiance (PCI) (le degre de lumiere correspondant a une inversion du rang de deux especes base sur leur croissance en hauteur) de semis dans une foret melangee de coniferes de la Sierra Nevada et nous l'avons utilise pour interpreter l'environnement lumineux produit par une eclaircie visant a diminuer les combustibles et par une coupe de jardinage par groupes avec reserve de gros arbres. Neuf des 21 paires d'especes avaient un PCI bien defini. Le PCI des especes tolerante et intolerante a l'ombre les plus communes (sapin argente(Abies concolor (Gordon & Glend.) Lindl. ex Hildebr.) et pin ponderosa (Pinus ponderosa Douglas ex P. Lawson & C. Lawson)) etait de 22,5 mol*[m.sup.-2] [jour.sup.-1] ou 41 % de la pleine lumiere. L'irradiance mediane du sous-bois a augmente de 9,2 mol*[m.sup.-2] [jour.sup.-1] (17 % de la pleine lumiere) dans la foret non traitee a 13 [m.sup.-2] [jour.sup.-1] (24 % de la pleine lumiere) dans l'eclaircie legere, 15,5 mol*[m.sup.-2] [jour.sup.-1] (28 % de la pleine lumiere) dans l'eclaircie moderee et 37 mol*[m.sup.-2] [jour.sup.-1] (67 % de la pleine lumiere) dans les ouvertures de la coupe de jardinage par groupes. Nous estimons que de 5 % a 20 % de la surface du sol des peuplements faiblement a moderement eclaircis auraient suffisamment de lumiere pour favoriser la croissance d'une espece intolerante a l'ombre plut?t que celle d'une espece tolerante comparativement a 89 % de la surface du sol dans le cas des ouvertures de la coupe de jardinage par groupes. Le PCI peut etre utilise comme un outil pour estimer l'implication sur la regeneration de la modification des traitements sylvicoles, comme l'augmentation de l'heterogeneite de l'eclaircie dans le but d'ameliorer la regeneration ou la reserve de gros arbres dans les ouvertures de la coupe de jardinage par groupes dans le but de maintenir les habitats fauniques. [Traduit par la Redaction], Introduction Tree canopy cover and density in many Sierra mixed-conifer forests are currently higher than before extensive logging and fire suppression by European-Americans during and after the gold rush era [...]

Under normal circumstances, vitamin D is mainly obtained from skin through the action of ultraviolet B irradiation on 7-dehydrocholesterol. It is further metabolized to 25-hydroxyvitamin D (25OHD), the major circulating vitamin D compound, and then to 1,25-dihydroxyvitamin D, the hormonal form. The major function of vitamin D compounds is to enhance active absorption of ingested calcium (and phosphate). This assists in building bone at younger ages and ensures that despite obligatory urinary losses, bone does not need to be resorbed to maintain blood calcium concentrations. Vitamin D compounds appear to have direct effects to improve bone and muscle function, and there is good, although not entirely consistent, evidence that supplemental vitamin D and calcium together reduce falls and fractures in older individuals. On the basis of calcium control and musculoskeletal function, target levels for 25OHD in blood are at least 50-60 nmol/l and there may be a case for higher targets of 75-80 nmol/l. There are vitamin D receptors in most nucleated cells and some evidence, although not consistent, that adequate vitamin D levels may be important in reducing the incidence of, or mortality from, some cancers and in reducing autoimmune disease. Adequate vitamin D may also allow for a normal innate immune response to pathogens, improve cardiovascular function and mortality and increase insulin responsiveness. Vitamin D levels are maintained better in the presence of adequate calcium intakes, more exercise and less obesity. Genetic variation may have an effect on vitamin D blood levels and response to treatment with vitamin D. doi: 10.1038/ejcn.2011.105; published online 6 July 2011 Keywords: vitamin D; sunlight; non-classical effects; calcium; deficiency, Introduction Although observations in people with severe vitamin D deficiency meant that vitamin D was well known for its importance in gut calcium absorption and bone and muscle function, more [...]

Background/Objectives: The goal of this work is to estimate the reduction in mortality rates for six geopolitical regions of the world under the assumption that serum 25-hydroxyvitamin D (25(OH)D) levels increase from 54 to 110 nmol/l. Subjects/Methods: This study is based on interpretation of the journal literature relating to the effects of solar ultraviolet-B (UVB) and vitamin D in reducing the risk of disease and estimates of the serum 25(OH)D level-disease risk relations for cancer, cardiovascular disease (CVD) and respiratory infections. The vitamin D-sensitive diseases that account for more than half of global mortality rates are CVD, cancer, respiratory infections, respiratory diseases, tuberculosis and diabetes mellitus. Additional vitamin D-sensitive diseases and conditions that account for 2 to 3% of global mortality rates are Alzheimer's disease, falls, meningitis, Parkinson's disease, maternal sepsis, maternal hypertension (pre-eclampsia) and multiple sclerosis. Increasing serum 25(OH)D levels from 54 to 110nmol/l would reduce the vitamin D-sensitive disease mortality rate by an estimated 20%. Results: The reduction in all-cause mortality rates range from 7.6% for African females to 17.3% for European females. Reductions for males average 0.6% lower than for females. The estimated increase in life expectancy is 2 years for all six regions. Conclusions: Increasing serum 25(OH)D levels is the most cost-effective way to reduce global mortality rates, as the cost of vitamin D is very low and there are few adverse effects from oral intake and/or frequent moderate UVB irradiance with sufficient body surface area exposed. doi: 10.1038/ejcn.2011.68; published online 6 July 2011 Keywords: cancer; cardiovascular disease; diabetes mellitus; respiratory infections; ultraviolet-B; vitamin D, Introduction Research on the health benefits of vitamin D has grown explosively during the past decade. According to the National Library of Medicine's PubMed database (www.pubmed.gov), as of 5 March [...]

Light strongly influences the circadian timing system in humans via non-image-forming photoreceptors in the retinal ganglion cells. Their spectral sensitivity is highest in the short-wavelength range of the visible light spectrum as demonstrated by melatonin suppression, circadian phase shifting, acute physiological responses, and subjective alertness. We tested the impact of short wavelength light (460 nm) on sleep EEG power spectra and sleep architecture. We hypothesized that its acute action on sleep is similar in magnitude to reported effects for polychromatic light at higher intensities and stronger than longer wavelength light (550 nm). The sleep EEGs of eight young men were analyzed after 2-h evening exposure to blue (460 nm) and green (550 nm) light of equal photon densities (2.8 x [10.sup.13] photons*[cm.sup.-2]*[s.sup.-1]) and to dark (0 lux) under constant posture conditions. The time course of EEG slow-wave activity (SWA; 0.75--4.5 Hz) across sleep cycles after blue light at 460 nm was changed such that SWA was slightly reduced in the first and significantly increased during the third sleep cycle in parietal and occipital brain regions. Moreover, blue light significantly shortened rapid eye movement (REM) sleep duration during these two sleep cycles. Thus the light effects on the dynamics of SWA and REM sleep durations were blue shifted relative to the three-cone visual photopic system probably mediated by the circadian, non-image-forming visual system. Our results can be interpreted in terms of an induction of a circadian phase delay and/or repercussions of a stronger alerting effect after blue light, persisting into the sleep episode. monochromatic light; non-image-forming visual system; spectral analysis; sleep electroencephalogram

Bright light can influence human psychophysiology instantaneously by inducing endocrine (suppression of melatonin, increasing cortisol levels), other physiological changes (enhancement of core body temperature), and psychological changes (reduction of sleepiness, increase of alertness). Its broad range of action is reflected in the wide field of applications, ranging from optimizing a work environment to treating depressed patients. For optimally applying bright light and understanding its mechanism, it is crucial to know whether its effects depend on the time of day. In this paper, we report the effects of bright light given at two different times of day on psychological and physiological parameters. Twenty-four subjects participated in two experiments (n = 12 each). All subjects were nonsmoking, healthy young males (18-30 yr). In both experiments, subjects were exposed to either bright light (5,000 lux) or dim light < 10 lux (control condition) either between 12:00 P.M. and 4:00 P.M. (experiment A) or between midnight and 4:00 A.M. (experiment B). Hourly measurements included salivary cortisol concentrations, electrocardiogram, sleepiness (Karolinska Sleepiness Scale), fatigue, and energy ratings (Visual Analog Scale). Core body temperature was measured continuously throughout the experiments. Bright light had a time-dependent effect on heart rate and core body temperature; i.e., bright light exposure at night, but not in daytime, increased heart rate and enhanced core body temperature. It had no significant effect at all on cortisol. The effect of bright light on the psychological variables was time independent, since nighttime and daytime bright light reduced sleepiness and fatigue significantly and similarly. sleepiness; core body temperature; cortisol; heart rate

Daylighting supports human activities with energy savings and provides positive effects to human health. In a dense urban environment, ensuring adequate daylight incident on windows is of the utmost importance [...]

The incidence of skin cancer is an increasing epidemiological problem, with over 40,000 new cases of skin cancers diagnosed annually in the UK. Most skin cancers are curable if treated [...]

Since the onset of the popularity of the package holiday in the 1960s and Coca Chanel making it de rigeurto have a tan an urban myth has cimulated. The myth [...]

SUMMARY There is growing concern about low vitamin D levels in the UK population, and children from a range of backgrounds are now presenting with rickets, the bone disease associated [...]