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PubMed2004

Evaluation of potential molecular markers for urban stormwater runoff.

Source specificity and persistence of several sulfur-polycyclic aromatic hydrocarbons (S-PAHs), nitro-PAHs (N-PAHs), and triphenylene were examined via analyses of stormwater runoff and wastewater effluent samples and spiked samples upon exposure to sunlight. Samples were collected during the 1997/1998 wet weather season from two major storm channels and four major wastewater treatment plants in southern California. Among the target compounds examined, 2-(4-morpholinyl)benzothiazole, dibenzothiophene, and triphenylene/chrysene were detected in storm runoff only. However, 2-(4-morpholinyl)benzothiazole appeared to degrade rapidly in seawater and sediment after sunlight exposure, which might impede its use as a runoff indicator. Dibenzothiophene and triphenylene also degraded quickly in sunlight-exposed seawater samples, but remained fairly abundant in sediments after six months of exposure to sunlight. They are by far the most promising candidates of urban runoff markers based on the criteria of abundance, source specificity, and persistence, although more research efforts are needed to ensure that no other sources would also contribute significantly to their presence in the aquatic environment.

Benzothiazoles↗

PubMed1999

Ultraviolet radiation induced signature mutations in photocarcinogenesis.

The photons of sunlight begin a series of genetic events in skin leading to cancer. UV signature mutations provide an alternative to inherited mutations as a way of identifying genes that are involved in cancer development. They augment epidemiologic and clinical data by serving as molecular evidence for the role of UV radiation in skin carcinogenesis. Signature mutations are present in TP53 and PTCH, two tumor suppressor genes responsible for non-melanoma skin cancer. We review evidence that clones of TP53-mutated cells are present in normal human and murine epidermis exposed to UVB and conclude that, in addition to being a tumorigenic mutagen, sunlight acts as a tumor promoter by favoring the clonal expansion of TP53 mutated cells. These combined actions of sunlight result in normal individuals' carrying a substantial burden of keratinocytes predisposed to cancer. Thus cancer involves both a single-cell problem and a multi-cell problem; in skin cancer, sunlight appears to drive both.

Adult↗

PubMed2006

Leaf turnover and growth responses of shade-grown saplings of four Shorea rain forest species to a sudden increase in light.

We tested the hypothesis that sapling growth following a sudden increase in solar irradiance is related to recovery from photoinhibition and the balance between rate of production of new leaves and rate of abscision of old leaves. Leaf gas exchange, chlorophyll fluorescence and relative growth rate (RGR) of stem basal area were measured following the sudden exposure of shade-grown (7% of full sunlight) saplings of four Shorea species to full sunlight. Sudden exposure to full sunlight resulted in an immediate and substantial reduction in dark-adapted quantum yield of photosystem II (Fv/Fm), followed by a gradual recovery in all species. Near light-saturated net assimilation rate (A max) and area-based leaf chlorophyll concentration ([Chl area]) also declined immediately after exposure. Eleven days after exposure, A max had recovered to pre-exposure values in all species, whereas [Chl area] had not recovered. Across species, RGR of stem basal area increased with increasing RGR of the number of leaves following exposure to full sunlight. The interspecific variations in RGR of stem basal area suggest that new leaf production is crucial for determining the potential growth of saplings following gap formation.

Biomass↗

PubMed2006

Roles of the transcription factor p53 in keratinocyte carcinomas.

The transcription factor p53 is mutated in most keratinocyte carcinomas (nonmelanoma skin cancers). In these tumours, the gene bears the trace of its mutagen, sunlight. Sunlight-induced p53 mutations are also seen in skin precancers and even sun-exposed skin, which harbours thousands of p53-mutant keratinocyte clones. Normal p53 is upregulated by sunlight exposure, after which it acts as a tumour suppressor in several ways: increasing DNA repair, arresting the cell cycle and inducing apoptosis of badly damaged keratinocytes. This UV-induced upregulation has been used as an assay for assessing the effectiveness of sunscreens. Once mutated, however, p53 renders cells apoptosis-resistant and therefore less sensitive to sunlight overexposure than normal cells. This reversal of roles drives clonal expansion of precancerous keratinocytes.

Basal Cell Carcinoma↗

PubMed2005

Experimental phytophotodermatitis.

BACKGROUND/AIMS: Phytophotodermatitis (PPD) is defined as a phototoxic reaction of the skin after contact with substances derived from plants and subsequent exposure to sunlight. It is a frequent disease in our outpatient clinics during summer because of contact with Tahitian lemon. Our objectives were to experimentally reproduce PPD in rats, to identify whether PPD is induced by minimal exposure periods to sunlight, to find what kinds of lemons and which parts of the lemon (the fruit juice or the peel juice) may trigger the disease; to know whether the use of sunblock prevents the reaction; and to perform light microscopy of the lesions to describe their histology. METHODS: Adult rats (Rattus norwegicus), three in each experiment, were used. After painting the rats with the fruit juice or the peel juice they were exposed to sunlight for 2.5, 5, 7.5, and 10 min. Tahitian and Sicilian lemons were used in the experiments. Biopsies with 3-mm punches of different times of exposure were performed. RESULTS: The peel juice of both lemons reproduced PPD, which was clinically evident after 48 h. When the peel juice was alone applied there was no reaction; moreover, exposure to sunlight alone triggered no reaction. Two and a half minutes of exposure time was sufficient to induce phototoxic reaction, which was time dependent (the longer the exposure the more intense the reaction). Histopathological studies showed epithelial time-dependent vacuolar degeneration. The use of sunblock diminished the intensity of the reaction but did not prevent it. CONCLUSION: PPD can be reproduced in an animal model. It may be caused by the peel juice of Tahitian and Sicilian lemon. Because of an extremely short time of exposure (2.5 min) is sufficient to induce PPD it is necessary to alert the population, of the need for caution when handling lemons, especially outdoors despite using sunblock.

Animals↗

PubMed1994

Photodegradation of sulfamethoxazole: a chemical system capable of monitoring seasonal changes in UVB intensity.

Sulfamethoxazole (SMX) in its nonionized form in aqueous solution has ultraviolet (UV) absorption that is maximal at 268 nm but extends through the ultraviolet-B (UVB) region. It was found to be extremely susceptible to photodegradation when exposed to artificial UV radiation through a Pyrex filter or to unfiltered natural sunlight. The SMX anion was more stable. The quantum yields of the photodegradation of both forms were determined by use of monochromatic light and ferrioxalate chemical actinometry, the values of 0.47 (pH 3.0) and 0.084 (pH 9.0) at the maximum absorption wavelengths (268 and 257 nm, respectively) being obtained. Using literature data on sunlight intensity, the photochemical shelf-life of SMX solutions exposed to direct sunlight was calculated for Sydney (latitude 33.5 degrees S) as a function of season of the year and verified experimentally. A fixed correlation was established between the rate constant for SMX degradation and UVB intensity measured by a radiometer, suggesting the capacity of this chemical system to monitor changes in the UVB region of sunlight.

Humans↗

PubMed2002

Geometrical gradients in the distribution of temperature and absorbed ultraviolet radiation in ocular tissues.

The geographical variations in the incidence of age-related ocular changes such as presbyopia and cataracts and diseases such as pterygium and droplet keratopathies have led to theories pointing to sunlight, ultraviolet radiation (UVR) exposure and ambient temperature as potential etiological factors. Some epidemiological evidence also points to an association of age-related macular degeneration to sunlight exposure. The actual distribution of sunlight exposure and the determination of temperature variations of different tissues within the anterior segment of the eye are difficult to assess. Of greatest importance are the geometrical factors that influence selective UVR exposures to different segments of the lens, cornea and retina. Studies show that the temperature of the lens and cornea varies by several degrees depending upon climate, and that the incidence of nuclear cataract incidence is greater in areas of higher ambient temperature (i.e., in the tropics). Likewise, sunlight exposure to local areas of the cornea, lens and retina varies greatly in different environments. However, epidemiological studies of the influence of environmental UVR in the development of cataract, pterygium, droplet keratopathies and age-related macular degeneration have produced surprisingly inconsistent findings. The lack of consistent results is seen to be due largely to either incomplete or erroneous estimates of outdoor UV exposure dose. Geometrical factors dominate the determination of UVR exposure of the eye. The degree of lid opening limits ocular exposure to rays entering at angles near the horizon. Clouds redistribute overhead UVR to the horizon sky. Mountains, trees and building shield the eye from direct sky exposure. Most ground surfaces reflect little UVR. The result is that highest UVR exposure occurs during light overcast where the horizon is visible and ground surface reflection is high. By contrast, exposure in a high mountain valley (lower ambient temperature) with green foliage results in a much lower ocular dose. Other findings of these studies show that retinal exposure to light and UVR in daylight occurs largely in the superior retina.

Animals↗

PubMed2006

Vitamin D deficiency in outpatients:--a Scottish perspective.

UNLABELLED: Vitamin D deficiency is common in older people and increases risk of falls, osteoporosis and fracture. This may be reduced with supplements. Recent Scottish guidelines recommend routine use of vitamin D and calcium for all older housebound, sunlight deprived or institutionalised people. Whilst many outpatients will undoubtedly meet these criteria, others who would benefit may not. We have determined the extent of vitamin D deficiency in older outpatients in our geographical area, to clarify further whether those found to be deficient, would receive supplementation under current guidelines. METHODOLOGY: 102 new patient referrals to outpatient clinics and day hospital were questioned over their social circumstances and activity levels, and had serum 25-Hydroxy Vitamin D (25(OH)D) levels measured in wintertime. RESULTS: Mean age was 79.6 (SD 7.3), 31.4% were housebound and 51.0% exposed their skin to sunlight. 72.6% had insufficient vitamin D levels [25(OH)D < 50 nmol/l], 27.5% of whom levels were frankly deficient [25(OH)D < 25 nmol/l]. Deficiency was significantly more common in females (p = 0.002), those attending the falls clinic or day hospital (p = 0.021), the housebound (p = 0.012) or patients who never exposed their skin to sunlight (p = 0.007). However, even in those patients who were outdoors frequently or who did expose their skin to the sun, the mean vitamin D levels remained insufficient [mean 25(OH)D = 45.6 (SD 26.2) nmol/l and 47.9 (SD 26.3) nmol/l respectively]. CONCLUSIONS: The prevalence of vitamin D deficiency is high in older outpatients in this geographical area. These patients may benefit from routine vitamin D and calcium, but currently many would not be targeted in recent Scottish Executive recommendations because they are not housebound and sunlight deprived.

Aged↗

PubMedDate not supplied

Photobiology of ocular melanocytes and melanoma.

There are two different types of ocular melanocytes and melanomas. Conjunctival melanocytes are located on the surface of the eye and are exposed to visible light and UV radiation. Recently, epidemiological studies demonstrated that sunlight plays a definite role in the occurrence of conjunctival melanoma, as it does in cutaneous melanoma. Uveal melanocytes consist of the iridal melanocytes, which are exposed to visible light and UV radiation; and the ciliary body melanocytes and choroidal melanocytes, which are not exposed to light radiation. Epidemiological studies demonstrated that sunlight may play a role in the occurrence of iridal melanoma, but may not be a major factor in the etiology of ciliary body and choroidal melanomas. Uveal melanocytes differ from epidermal melanocytes in that epidermal melanocytes respond to UV radiation and skin color becomes darker after exposure to sunlight; but uveal melanocytes do not respond to UV radiation and the iris color remains stable after exposure to sunlight. Recently, in vitro studies indicate that this phenomenon is determined both by cellular factors and environmental factors.

Animals↗

PubMed2006

Long-lasting effects of a Bacillus thuringiensis serovar israelensis experimental tablet formulation for Aedes aegypti (Diptera: Culicidae) control.

Dengue is a growing public health problem in many tropical and subtropical countries worldwide. At present, the only method of controlling or preventing the disease is to eliminate its vector, Aedes aegypti (L.) (Diptera: Culicidae). In the current study, an experimental larvicide tablet formulation XL-47 based on Bacillus thuringiensis serovar israelensis (Bti) and containing 4.8% of technical powder was developed. This formulation was evaluated against Ae. aegypti in three different sets of experiments, under field-simulated conditions: two experiments were indoors and under partial sunlight exposure and one experiment was outdoors with sunlight exposure. Larvae were added throughout the experiment two times per week, and the residual larvicidal activity was recorded daily. Pupal formation was reduced in the containers with Bti by > 80% in relation to the containers without treatment for 12 wk; to our knowledge, this is the longest period of control reported for a Bti tablet formulation outdoors under sunlight exposure. Moreover, samples from the top, middle, and bottom of the water column were collected to perform bacterial plate counts and toxicity assays. The Bti population and the active ingredient of the tablet formulation remained mainly at the bottom of the containers and mosquito larvae reached the formulation by diving and shredding the tablet's material. In conclusion, the experimental tablet formulation XL-47 showed an inhibition of pupal formation that lasted for long periods under sunlight exposure.

Aedes↗

PubMed1968

[The Influence Of Ultraviolet Irradiation Upon The Development And Infectivity Of Hookworm Larvae]

The eggs and rhabditoid larvae of canine hookworm were irradiated with ultraviolet rays for one hour at a distance of 10, 20, 30, and 40 cm. The infective stage larvae of the same parasites were irradiated for l, 3, 5 and 14 hours from the same distances. The infective larvae were also exposed under direct sunlight for l, 2, 3 and 4 hours. PARASITES: Ancylostoma caninum was used. Eggs were collected in vitro from female adult worms. The worms were kept at 37 degrees C in petri-dish filled with Kreb's Ringer solution. There was an average of two cell stages, and they were used as early as possible before the morula stage. Rhabditoid larvae were obtained by culture of the above eggs for twenty-four hours in 25 degrees C incubator. The larvae reached the infective stage in seven days culture at the same condition. IRRADIATION OF ULTRAVIOLET RAY: Kingston ultraviolet light (100 volt, 10 watt, 50 cycles, 0.230 ampere) was used. The potential U.V.R. power was 1.8 watts. The distances between the material and the light were 10, 20, 30 and 40 cm at a temperature of 25 degrees C in each case. The samples were smeared on the tile in order to keep them in saturated moisture. Fully wetted ten ply gauze was laid underneath the tile. The tile was surrounded by 2 x 5 cm rectangular piece of glass in order to prevent the spread of the larvae to the outside. All of the samples received irradiation for one hour and were cultured for a period of seven days. The hatching of the egg and the development of the larvae were observed. For the purpose of the study, the infectivity and pathogenicity of the irradiated samples, were inoculated into mice orally. The lungs, livers and carcass were examined three days after the infection. A routine pathological examination of the organs was also carried out. In order to study the eggs productivity, the larvae were given to the proper host, dog. The eggs in the feces were examined from three to 6 weeks after infection, both quantitatively and qualitatively. As a supplementary experiment, the infective larvae of canine hookworm were exposed four hours under direct sunlight (September 25), and the infectivity and pathogenicity of the host were examined. HATCHING, DEVELOPMENT AND INFECTIVITY OF IRRADIATED EGGS: Hatchability of the irradiated group for one hour according to the distance from the light to the sample were 48.0 % at 10 cm, 60.3 % at 20 cm, 85.2 % at 30 cm and 88. 2 % at 40 cm respectively. None of them developed to the infective stage. They remained rhabitoid for several days and were destroyed. None was found alive in the host. 93.0 % of the control group hatched and developed to the infective stage. DEVELOPMENT AND INFECTIVITY OF IRRADIATED RHABDITOID LARVAE: None of the irradiated group reached the infective stage. Under irradiation they coiled and died soon after straightening out again. Only the group irradiated at the distance of 40cm survived for six days. They finally granulated. There was no manifestion of irradiated larvae alive in the host tissue. LIFE SPAN, INFECTIVITY, PATHOGENICITY AND EGG-PRODUCTIVITY OF THE IRRADIATED INFECTVE STAGE LARVAE: All were destroyed in the group of fourteen hours irradiation at 40 cm distance. Thirteen precent survived in the five hours irradiation group at the same distance. The survivability of larvae was reduced by the period of irradiation and at the shortest distance. The infectivity to mice was only 0.8 % at 30 cm, and 8.2 % at 40 cm in the three hour irradiation group. The recovery of the infected larvae from the host tissues was reduced as the irradiation period was increased and the distance shortened. The pathogenicity was paralleled with the vitality of the irradiated larvae. From the groups of one hour irradiation and ten cm distance, three hour irradiation and ten to thirty cm distance, the egg-productivity was all negative. But as the irradiation period decreased and the distance lengthened the egg-productivity tended closer to normal. The infective stage larvae which were exposed to direct sunlight were destroyed within three hours, but survived 81 % in the one hour exposure group and 20 % in the two hour exposure group. The summary of the results is as follows: 1. The hatching of eggs was reduced to half for one hour irradiation at the ten cm distance. Even hatched larvae did not develop to infective stage. 2. Infectivity was inhibited by the irradiation to at the ten cm distance for one hour. About ten percent of the irradiated infective stage larvae were recovered from the infected animal among the group of 40 cm distance for one hour. The egg-productivity became lower in the group of one hour irradiation at 40 cm distance. 3. The pathogenicity of the irradiated group was mild compared to the control group. 4. The direct sunlight destroyed the infective stage larvae within three hours. In general, the ultraviolet ray showed the inhibitory action in the hatching, development, pathogenicity and egg-productivity of the hookworm. The grade was paralleled with the period of irradiation and reversed to the distance between the light and samples.

Journal Article↗

PubMed2005

Photodecomposition and phototoxicity of natural retinoids.

Sunlight is a known human carcinogen. Many cosmetics contain retinoid-based compounds, such as retinyl palmitate (RP), either to protect the skin or to stimulate skin responses that will correct skin damaged by sunlight. However, little is known about the photodecomposition of some retinoids and the toxicity of these retinoids and their sunlight-induced photodecomposition products on skin. Thus, studies are required to test whether topical application of retinoids enhances the phototoxicity and photocarcinogenicity of sunlight and UV light. Mechanistic studies are needed to provide insight into the disposition of retinoids in vitro and on the skin, and to test thoroughly whether genotoxic damage by UV-induced radicals may participate in any toxicity of topically applied retinoids in the presence of UV light. This paper reports the update information and our experimental results on photostability, photoreactions, and phototoxicity of the natural retinoids including retinol (ROH), retinal, retinoid acid (RA), retinyl acetate, and RP (Figure 1).

Animals↗

PubMedDate not supplied

Delivery of vitamin E to the skin by a novel liquid skin cleanser: comparison of topical versus oral supplementation.

Topical supplementation represents an attractive approach to mitigate environmentally induced deficiencies of skin vitamin E (alpha-tocopherol). We report here the impact of natural sunlight on stratum corneum (SC) vitamin E and also compare the effectiveness of dietary supplementation to topical application as a way to increase vitamin E in the superficial layers of the SC. The effects of natural sunlight, 30 minutes of midday sunlight, were measured on two separate occasions. Vitamin E in the surface layers of the SC was measured by HPLC after ethanol extraction. Under these relevant conditions, vitamin E in the superficial SC was reduced in a dose-dependent manner by 50-65%. In a followup study, panelists entered into a randomized, double-blind, vehicle-controlled study. In this study, one group washed their skin once daily for one minute with a commercially available body wash containing 0.15% vitamin E and 0.10% vitamin E acetate, while the second group used a body wash without vitamin E but also supplemented their diet with 400 IU alpha-tocopherol (18 x RDI). Not surprisingly, only dietary supplementation increased serum vitamin E (approximately twofold). Although both treatment modalities increased SC vitamin E, topical delivery was significantly more effective (53-fold vs baseline) than dietary delivery (eightfold vs baseline). Moreover, only topical delivery increased SC vitamin E acetate (19-fold vs baseline). The results reported here indicate that vitamin E in the superficial layers of the SC is depleted readily by even a brief exposure to sunlight and that use of a vitamin E body wash can substantially increase the vitamin E in this superficial layer more effectively than dietary supplementation.

Administration, Oral↗

PubMed2004

[Response of photosynthesis and antioxygenic enzymes in seedlings of three tropical forest tree species to different light environments].

This paper studied the response of photosynthesis, chlorophyll a fluorescence and 3 antioxygenic enzyme activities in the seedlings of a pioneer species (Mallotus barbatus) and two endangered sub-canopy tree species (Litsea pierrei var. szemaois and L. dilleniifolia) in Xishuangbanna tropical rain forest to different light environments. Three light regimes (50%, 25% and 8% full sunlight) were designed for the seedlings. The largest values of maximum photosynthetic rates (Pmax) of L. pierrei var. szemaois and L. dilleniifolia were documented at 25% and 8% sunlight, respectively, which showed that the two sub-canopy species had poor ability in photosynthetic acclimation to high light. In contrast, the Pmax of M. barbatus increased with light level. During a day, the maximum photochemical efficiency (Fv/Fm) of the photosystem II in all the three species grown under three light levels showed minimum values at noon, and the lowest Fv/Fm values were shown in seedlings at 50% sunlight. Under 50% sunlight, the Fv/Fm values at dawn were lower in L. dilleniifolia than in the same species under other two light levels, indicating that sustained photoinhibition occurred in this case. The contents of malondialdehyde (MDA), H2O2, and activities of ascorbate peroxidase (APX), superoxid dismutase (SOD), catalase (CAT) of both L. pierrei var. szemaois and M. barbatus increased with stronger irradiance, which revealed that these two species were able to alleviate photodamage under high light stress by increasing their antioxigenic activities. But, high content of MDA revealed that L. dilleniifolia was probably suffered from membrane damage. In conclusion, our data revealed that the pioneer species M. barbatus had a high capacity to acclimate to different light environments, particularly high light, while the two subcanopy Litsea species had poor ability in acclimation to high light. Based on the findings of the present study, we suggest that the small populations and endangered status of both L. pierrei var. szemaois and L. dilleniifolia in natural environment could be partially due to their poor flexibility in response to changed light environment resulted from habitat fragmentation.

Catalase↗

PubMed1998

Demographic characteristics, pigmentary and cutaneous risk factors for squamous cell carcinoma of the skin: a case-control study.

We conducted a case-control study of squamous cell carcinoma of the skin (SCC) in a cohort of people followed from 1987 to 1994. Subjects were residents of Geraldton, Western Australia, who were between 40 and 64 years of age in 1987. On 2 occasions, in 1987 and 1992, dermatologists examined participants for skin cancers. Subjects were also asked on several occasions about skin cancers that they had had treated. Migrants to Australia had reduced risks of SCC. Furthermore, people who migrated to Australia early in life or, equivalently, lived in Australia for a long time had a higher risk than immigrants who arrived later in life or more recently. People who had southern European ancestry had a much lower risk of SCC than other subjects, most of whom were of British or northern European origin. Among Australian-born subjects of British or northern European ancestry, the skin's sensitivity to sunlight was strongly associated with SCC. The pigmentary traits of hair colour, eye colour and skin colour showed weaker associations. The degree of freckling on the arm was strongly predictive of risk. The risk of SCC increased strongly with increasing evidence of cutaneous solar damage and was most strongly associated with the number of solar keratoses. Our results show that sensitivity to sunlight and high levels of exposure to sunlight are important determinants of the risk of SCC.

Adult↗

PubMed2002

Occurrence of farmer's lung disease is relevant to meteorological conditions: a 20-year follow-up field survey analysis.

BACKGROUND: A field survey on farmer's lung disease (FLD) in a dairy farming community in the northernmost district of Japan has been in progress since 1978. METHODS: The correlation between the number of FLD occurrences year by year and dairy farming conditions and meteorological data were compared. RESULTS: Thirty-four FLD cases had occurred in a 20 years period. Average number of days below freezing during the harvest season the year prior to FLD occurrence were significantly smaller than other years (2.1 +/- 0.7 [SE] days, 4.6 +/- 0.7 days, P < 0.05, respectively). Average annual sum of the sunlight hours in the years before the years with FLD occurrence was significantly smaller than those without FLD occurrence (1457.1 +/- 114.0 hr, 1811.3 +/- 97.7 hr, P < 0.05, respectively) and was also significantly smaller for the sunlight hours during a harvest season (821.9 +/- 60.2 hr, 1023.2 +/- 52.7 hr, P < 0.05, respectively). CONCLUSIONS: Temperature and sunlight hours closely associated with the FLD occurrence.

Dairying↗

PubMed1994

The effect of light on the vitamin B2 and the vitamin A content of cheese.

Edam type cheese was exposed to sunlight at ambient temperature and to fluorescent light at 5 degrees C. The loss of vitamin B2 (riboflavin) and vitamin A was monitored in both the surface and inner layers of the cheese and the results compared with control samples kept in the dark. The loss of riboflavin when exposed to sunlight was shown to be primarily a surface effect but losses of vitamin A were similar throughout the cheese. When exposed to fluorescent light at 5 degrees C and monitored at intervals for 10 days the loss of riboflavin was still greatest at the surface but a trend to lower values than the control was evident throughout the cheese. Vitamin A losses followed a different pattern in both sunlight and fluorescent light. There was a heavy initial loss throughout the cheese. Under fluorescent light this was followed by a period in which further loss was mainly in the surface layer. Vacuum packaging reduced the loss of riboflavin but had no effect on the loss of vitamin A.

Cheese↗

PubMed2005

Seasonal mood variation in the elderly: the Leiden 85-plus study.

BACKGROUND: The influence of seasonal changes on mood and behaviour is called seasonality. The prevalence of seasonality in elderly subjects is unknown. AIM: To investigate the seasonality pattern in mood and behaviour at old age. METHODS: All subjects from the Leiden 85-plus Study with an MMSE score of 19 or more were assessed for depressive feelings at age 85 and yearly thereafter. The influence of time of the year, duration of sunlight, daylight, and rain on the prevalence of depressive symptoms was assessed using linear mixed models for repeated measurements. RESULTS: There was no significant seasonal pattern in the data (p=0.44). Within each of the four years of observation (85, 86, 87 and 88 years) and all years combined, there was also no significant association between the one-month cumulation of duration of sunlight, daylight, or rain and the score on the GDS (all p-values >0.05). The results of either the one week or three-month accumulation of sunlight, daylight, or rain were comparable to the one-month results. CONCLUSIONS: Estimates of prevalence of seasonality reported in the literature might be overestimated or a remarkable difference between young and old subjects exists.

Affect↗