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Results indicate that diffused sunlight determines in the molecules of all-trans-retinal, 9-cis-retinal and 11-cis-retinal a process of photoinduction with the formation of an unknown photoproduct.
The differences of soil and air environments, crop growth, development and diseases, and water use efficiency of seeping irrigation from furrow irrigation were studied. Results indicated that compared with furrow irrigation, seeping irrigation could increase soil waterstable granular by 81.4%, soil porosity by 29.0% and soil temperature by 1.1-1.7 degrees C respectively, decrease bulk density by 21.2% and relative air humidity by 13.4% respectively, and save irrigation water by 36.7%. In addition, seeping irrigation could also accelerate crop maturity and increase yield, reduce crop diseases and production cost. Therefore, seeping irrigation was an ideal irrigation technique in sunlight greenhouse at present.
Traditional dietary habits and the living style in Spain should theoretically be enough to assure a healthy vitamin D status: a very high fish intake and one of the highest sun exposure rates of all countries in Europe. However, in spite of this, there is a high percentage in the elderly showing low vitamin D serum values. This paper is part of the Euronut-SENECA study, a major multicentre survey assessing the nutritional status in the elderly from 19 centres over 12 countries in Europe. In it, the vitamin D status in 55 healthy individuals from Spain has been studied and assessed by measuring dietary and supplemental vitamin D intakes; the influence of sunlight exposure such as physical activity, permanence in the sun, clothing, etc.; and 25-hydroxyvitamin D [25 (OH)D] serum concentration. The mean dietary intake was 1.3 +/- 1.5 micrograms/day, being fish, and specially fatty fish, the main source (62%). Of the total, 85% of the elderly did not reach the Spanish recommended dietary intake (2.5 micrograms/day). The mean 25(OH)D serum level was 25 +/- 14.7 nmol/l and there was a high percentage with deficit (13%) (8.4 +/- 1.9 nmol/l) and marginal (62%) (19.8 +/- 4.2 nmol/l) levels. People who usually walked 1.9 +/- 1.3 hours/day or stayed in the sun "every day" or "as much as possible", had higher (p < 0.05) serum 25 (OH)D concentrations (27.7 +/- 2.4 nmol/l and 31.3 +/- 3.7 nmol/l, respectively) than people who did not (16.6 +/- 1.2 nmol/l and 21.3 +/- 2.1 nmol/l, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
One of the major technical challenges in calculating solar irradiance on the human form has been the complexity of the surface geometry (i.e. the surface-normal vis-a-vis the incident radiation). Over 80% of skin cancers occur on the face, head, neck and back of the hands. The quantification, as well as the mapping of the anatomical distribution of solar radiation on the human form, is essential if we are to study the etiology of skin cancers or cataracts or immune system suppression. Using advances in computer graphics, including high-resolution three-dimensional mathematical representations of the human form, the calculation of irradiance has been attained to subcentimeter precision. Lighting detail included partitioning of direct beam and diffuse skylight, shadowing effects and gradations of model surface illumination depending on model surface geometry and incident light angle. With the incorporation of ray-tracing and irradiance algorithms, the results are not only realistic renderings but also accurate representations of the distribution of light on the subject model. The calculation of light illumination at various receptor points across the anatomy provides information about differential radiant exposure as a function of subject posture, orientation relative to the sun and sun elevation. The integration of a geodesic sun-tracking model into the lighting module enabled simulation of specific sun exposure scenarios, with instantaneous irradiance, as well as the cumulative radiant exposure, calculated for a given latitude, date, time of day and duration. Illustration of instantaneous irradiance or cumulative radiant exposure is achieved using a false-color rendering--mapping light intensity to color--creating irradiance or exposure isopleths. This approach may find application in the determination of the reduction in exposure that one achieves by wearing a hat, shirt or sunglasses. More fundamentally, such an analysis tool could provide improved estimates of scenario-specific dose (i.e. absorbed radiant exposure) needed to develop dose-response functions for sunlight-induced disease.
Within 50 years, if current trends continue, 50 million elderly Americans will suffer visual impairment from macular degeneration or cataract. However, available evidence indicates that this impending crisis of visual health can be minimized by a simple, safe, inexpensive, and practical means of prevention. Cataract and macular degeneration are the ultimate consequences of normal aging, a lifelong process of deterioration. Three major causes of ocular deterioration have been identified: oxygen, heat, and solar radiation. Among these, the radiation hazard is readily accessible to human intervention. The lens is damaged by ultraviolet radiation in sunlight, whereas the retina can be harmed by high-energy visible radiation (the "violet and blue"). Use of sunglasses that block all ultraviolet radiation and severely attenuate high-energy visible radiation will slow the pace of ocular deterioration and delay the onset of age-related disease, thereby reducing its prevalence. A 20-year delay would practically eliminate these diseases as significant causes of visual impairment in the United States.
To assess the number and types of workers occupationally overexposed to sunlight, we interviewed a national sample of 450 employers in occupational categories involving outdoor work and 5000 of their workers. The workers were assigned to 5 overall risk levels, according to combinations of skin sensitivity to ultraviolet radiation (UVR), total weekly hours of outdoor occupational sun-exposure between 0800 and 1400, and percent of skin surface exposed during outdoor work in the summer. Based on this information it was estimated that out of a total of 379,000 Israeli workers in outdoor occupations, 167,000 (44%) are at increased risk for skin cancer (risk levels 1-3) due to occupational exposure to solar UVR. Their estimated lifetime skin cancer risk is 1.5- to 20-fold higher than that of workers at low or minimal risk levels (4-5). The characteristics of those interviewed with regard to occupation, duration of solar exposure, demographic traits, geographic location, degree of risk awareness and protective measures undertaken, provide a data base for effective intervention to reduce the hazards of occupational solar exposure in Israel. We estimate that an appropriate preventive program may reduce skin cancer in Israeli men to half its current rate.
Childhood exposure to ultraviolet (UV) radiation in sunlight may be an important risk factor for later development of skin diseases. We quantified the UVB radiant exposure on the wrist and face of children performing mixed outdoor activities at a summer camp. Polysulfone film badges were attached directly to the skin for several hours and simultaneously were used to measure ambient UVB levels. The results for the ratio of site-specific exposure to ambient exposure indicate a high degree of intersubject variability, a parity of samples taken in right and left positions, and a significantly higher exposure on the wrist compared with the face. The technique was well accepted by the subjects but some badges could not be read because of loss or damage. Measurement of exposure ratios in additional settings as well as data on childhood activity patterns are needed for an overall assessment of childhood exposure.
Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported.
Recently, favourable results have been reported from oral L-phenylalanine (Phe) combined with UVA/sunlight irradiation (Phe-UVA) in the treatment of vitiligo. In the present pilot study vitiligo patients were treated on a thrice weekly scheme of 50 mg Phe.kg-1 body weight and exposed to sunlight as a source of UVA. An observed 81% response on the skin disorder correlates with earlier figures; 43% responded within 3 months. The self-controlled treatment includes the risk of over-irradiation, as possibly happened with one patient. The repigmentation was predominantly of follicular pattern. The assumption that Phe plays a central biochemical regulatory role in melanin, catecholamine and antibody synthesis forms an attractive challenge for the explanation of repigmentation and requires further investigation.
The treatment of psoriasis with psoralen and direct sunlight has been reported as successful but unpredictable because of its dependence on prevailing weather conditions which are subject to marked daily and seasonal variations. A study carried out in a locale nearly ideal because of its reliable year-round sunshine produced complete remission of all exposed plaques in twelve consecutive patients.
A sausage of 4 cm diameter and 15 cm length was chosen as a model of a part of human extremities. On the snowfield the model was stood on end and its temperature was recorded continuously by means of thermistor thermorecorder. The conclusions are as follows: In fine weather the temperature directly under the sunny surface of a model rose higher than the air temperature by 18 degrees C in the most remarkable case. Even in cloudy weather it rose fairly though lower than in fine weather. The rise of a model temperature became higher in February than in January. Even at a depth of 1.0 cm the temperature rose fairly though lower than directly under the surface. The temperature of the shady side of a model was equal to air temperature or snow temperature. It is presumed from these data that the temperature of a human dead body on snowfield becomes higher and reaches a optimum temperature for putrefaction at least partly by the radiation of sunlight. The presumption is supported by our experiences at the autopsies in cold district.
Chronic and heavy sun exposure will insidiously induce changes in human skin during the course of many years. These changes include wrinkles, atrophy, cutis rhomboidalis nuchae, yellow papules and plaques of the face, colloid milium, telangiectasis, diffuse erythema, diffuse brown pigmentation, ecchymoses, freckles, actinic lentigo, nevi, Favre-Racouchot syndrome, poikiloderma of Civatte, actinic keratosis, basal cell carcinoma, squamous cell carcinoma, melanoma, actinic lichen planus, actinic reticuloid, porphyria cutanea tarda, and erythropoietic protoporphyria. In particular, we describe the clinical appearance of the benign changes caused by chronic sunlight exposure.
Total plasma 25-hydroxyvitamin D (25-OHD) and its components 25-OHD2 and 25-OHD3 were measured during the winter in young and elderly healthy persons and in elderly women patients in a long-stay mental hospital. The long-stay patients had no exposure to sunlight or other ultraviolet irradiation, but their diet alone maintained an average total 25-OHD level of 16 nmol/l (range, 10.3-26.5 nmol/l), with most values within the ranges observed in the other two groups, although the average value was lower. The plasma 25-OHD2 which is derived exclusively from vitamin D2 in the diet was similar in all three groups and the vitamin D intake was also similar in the two elderly groups. 25-OHD3 is obtained from the diet as well as from the skin and in the elderly patients the diet alone maintained equal concentrations of 25-OHD2 and 25-OHD3. These findings taken together suggest that the diet accounted for 70 per cent of the total 25-OHD in the active elderly in winter compared with 50 per cent in the young subjects. In all our subjects, young or old, the diet was the major source of vitamin D.
Vitamin D status was assessed in 929 men and women aged 65 years and over during a nutrition survey lasting 56 weeks. Concentrations of 25-hydroxyvitamin D (25-OHD) measured in plasma samples showed a seasonal variation, being significantly higher in summer than in winter, and correlated with exposure to sunlight as measured by a 'sunshine score'. Regression analysis showed that 25-OHD concentrations fell with advancing age in both men and women and in summer and winter and approached the same value (about 10 ng/ml) at about the age of 95. This fall has implications in the occurrence of osteomalacia among the elderly and the increasing incidence with age of fractures of the femoral neck.
The coexistence of bullous pemphigoid and psoriasis has previously been noted. In most patients, the bullous lesions start during PUVA or UVB therapy of psoriasis. We report on a psoriatic patient who developed bullous pemphigoid approximately three to four weeks after discontinuing PUVA treatment, and then three to four weeks after exposure to natural sunlight. Delayed induction of bullous pemphigoid has not been previously reported, and it raises the question of ultraviolet therapy inducing subclinical or latent bullous pemphigoid in psoriatic patients.
Sunlight destroyed 83 and 50% of the toxin added to casein and groundnut cake flour, respectively. Equilibrium dialysis revealed that both casein and groundnut protein bind aflatoxin but the toxin bound to casein appeared more photo-labile than that bound to groundnut protein.
OBJECTIVE: To determine serum 25-hydroxyvitamin D3 [25(OH)D3] and its 1-hydroxylated metabolite [1,25(OH)2D3] and relate them to anthropometric data, life-style habits, blood pressure and selected biochemical analytes. DESIGN: Random population samples of men and women. SETTING: Göteborg, Sweden, population size 450,000 inhabitants. The study was performed within the framework of the WHO MONICA Project. SUBJECTS: 2000 randomly selected subjects were invited to the main MONICA screening. Out of those 1421 (71%) participated. Fifty individuals in each of four age-groups, 25-64 years, were selected at random for the present analyses (184 men and 198 women). RESULTS: The concentration of 25(OH)D3 was similar in both sexes whereas 1,25(OH)2D3 concentration was higher in women than in men (P = 0.01). 25(OH)D3 correlated positively to sun exposure, physical activity and negatively to intact parathyroid hormone (PTH) in both sexes, and also negatively to blood pressure in men. The remaining significant relationship for 25(OH)D3, when age and sun exposure were taken into account in multivariate analyses, was a negative correlation to intact PTH in both sexes. 1,25(OH)2D3 correlated positively to intact PTH in both men and women, negatively to height in men, positively to fibrinogen in men and positively to psychological stress and osteocalcin in women. When all variables were included in multivariate analyses 1,25(OH)2D3 concentration correlated negatively to age and positively to intact PTH and osteocalcin in both sexes together. CONCLUSIONS: Sunlight was the only external factor that influenced 25(OH)D3 concentration whereas 1,25(OH)2D3 was unaffected by sun exposure. 1,25(OH)2D3 was not related to environmental or life style factors but declined by age and correlated positively to intact PTH and osteocalcin. SPONSORSHIP: Grants from the Swedish Medical Research Council and the Swedish Heart and Lung Foundation.
A severe case of phytophotodermatitis occurred in a patient who had spent several hours walking through an area densely populated with Cneoridium dumosum. This patient's co-worker experienced a similar reaction after undergoing patch testing of an area of skin and exposing it to sunlight. Voluntary patch testing by one of the authors produced a reaction consistent with the other two cases. Approximately twenty other cases were described by a U.S. Fish and Wildlife Service ranger in students who came into contact with the plant during a field trip with him to Baja California, Mexico. Cneoridium dumosum is a common native bush that grows in the chaparral vegetation zone of southern California and Baja California, Mexico. In a search of Poisindex, Medline, Agris International, and Agricola databases, no previous reports of toxic exposures were found.