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PubMed1996

UV-induced cutaneous photobiology.

Ultraviolet radiation (UVR) present in sunlight is a major environmental factor capable of affecting human health and well being. The organ primarily affected by UVR is the skin, which is composed of a variety of different cell types. Here, UVR is needed for production of active vitamin D as well as producing undesirable effects such as sunburn, premature cutaneous photoaging, and promoting skin cancer development. Depending on the radiation dose, UVR influences virtually every cutaneous cell type investigated differently. Since the end of the nineteenth century, sun exposure has been known to induce skin cancer, which is now the human malignancy with the most rapidly increasing incidence. In several experimental models, mid-range UVR has been demonstrated to be the major cause of UV-induced cutaneous tumors. The stratospheric ozone layer protecting the terrestrial surface from higher quantum energy solar radiation is being damaged by industrial activities resulting in the possibility of increased UVR exposure in the future. Investigations in the field of experimental dermatology have shown that within the skin an immunosurveillance system exists that may be able to detect incipient neoplasms and to elicit a host responses against it. This article reviews the literature on studies designed to investigate the effects of UVR on cutaneous cellular components, with special focus on the immune system within the skin and the development of UV-induced cancer.

Apoptosis↗
PubMed2000

[Vegetable food resources with agroindustrial potential from Guatemala. Manufacture of vegetable milk from the seed of morro fruit (Crescentia alata)].

The objective of the present study was to establish the conditions for the preparation of vegetable milk from the morro or jicara seed, and to characterize the products, the milk and the residue for their partial chemical composition and acceptability. From the ripe fruit, the seeds were obtained by maceration in water for 3.5 hrs, obtaining seed yields of 80%. This seed contained 38% fat and 26% protein on a dry weight basis. The harvested seed was then dehydrated to 9-12% moisture by exposure to solar energy. A similar lot was lightly roasted by heating on a hot surface for 10 min at 90-110 degrees C. The seed was used for the extraction of solubles or the vegetable milk. Water extraction with up to 10 minutes of mechanical blending gave low yields of soluble solids (4.66 +/- 0.10 to 4.98 +/- 0.07%) and low contents of fat, protein and ash in the extract with sun dried seed and significantly lower with the lightly roasted seed (3.0 +/- 0.05 to 3.4 +/- 0.03%). Due to the low yields of total soluble solids and to the low nutrient content by aqueous extraction, new extractants were used consisting of buffer solutions at pH 7.8, or 8.5 with and without saline solution at 0.5% concentration. With these solutions greater amounts of solids were extracted with a higher content of nutrients. The milk prepared from the sun dried seed and extracted with buffer at pH 8.5 and saline solution (0.5%) gave an extract with 9.85% of total solids, 3.37% protein, 4.44% fat. The extraction with roasted seed gave significantly lower yields. The residue of the extraction contained 21.47% fat and 14.72% protein. With the use of buffers and saline solution the extracts had better acceptability, with the milk produced from sun dried seed having better organoleptic characteristics in comparison with soy milk (5.84 vrs 3.76), however it was of lower acceptability when tested against cows milk (5.7 vrs 7.7). The isoelectric point of the extracted protein was between 4 4.45.

Beverages↗
PubMed2000

[Relationship between light and regeneration character of Huangshan pine].

The growth and physiological characters of 1-3 years old Huangshan pine seedlings in pure and mixture plots with four different transparancy were determined, and the germination percentage of seeds and their complex stressing vigour were tested. Meanwhile, the regeneration mechanism of Huangshan pine in natural forest was studied in this paper. The results showed that the plumpness of seeds was 65%, the germination percentage was 27%, and the complex stressing vigour was 26%. The lower germination percentage affected the reproduction of Huangshan pine. The photosynthetic rate was more affected by solar energy, but less by humidity and surface temperature. With high light composation, Huangshan pine's regeneration under forest was difficult. The seedlings of Huangshan pine in mixed coniferous and broadleave tree plots were at a disadvantage because of slow growth and insufficient light.

Ecosystem↗
PubMedDate not supplied

[Photosynthesis and oxygenation of the earth's atmosphere].

Based on the contemporary data concerning photosynthesis as a global biogeochemical mechanism of solar energy utilization and organic matter and oxygen production, the formation of photosynthesis in the Proterozoic is considered, as well as its role in transformation of the pre-Proterozoic oceanic hydrosphere and the Earth's atmosphere from a reduced to an oxidized state. Photosynthesis is considered the longest stage of organic world evolution. The problem of production of "excessive" oxygen is considered, which entered and is entering the atmosphere through the oceanic hydrosphere and determines the process of its organization.

Atmosphere↗
PubMed2001

[Study on schistosomiasis control strategy in Ertan reservoir].

OBJECTIVE: To explore means and strategies of preventing the spread of schistosomasis transmission due to the building of Ertan Dam. METHODS: To eliminate the infection sources and Oncomelania snails. To install concrete irrigation and piping system of water supply. To encourage the immigrants to build methane-generating tanks and improve sanitary facilities and conditions for families who live near the water-retaining line. RESULTS: 2,360 people and 152 cattle were treated for schistosome infection. Mollusciciding and environmental modification were made for eliminating snails at an area of 3,634,580 m2 and 67,105.5 m2 respectively. The length of concrete irrigation and piping system installed was 51.13 and 104.895 km respectively. Methane-generating tanks, water-heating instruments using solar energy and other sanitary facilities were established in 1,781 households. After three-year intervention, no infected snails were found and no infected human being, cattle and wild rats were detected. CONCLUSION: Schistosomiasis control was financially supported since the very beginning of the Ertan Dam project, which provided a condition for sustainable development. Continued surveillance of snails and infection sources should be carried out, which will provide scientific basis for schistosomiasis control in the Three Gorges region as well as other new projects of hydropower and water conservancy in endemic area.

Animals↗
PubMed2003

The artificial water cycle: emergy analysis of waste water treatment.

The artificial water cycle can be divided into the phases of water capture from the environment, potabilisation, distribution, waste water collection, waste water treatment and discharge back into the environment. The terminal phase of this cycle, from waste water collection to discharge into the environment, was assessed by emergy analysis. Emergy is the quantity of solar energy needed directly or indirectly to provide a product or energy flow in a given process. The emergy flow attributed to a process is therefore an index of the past and present environmental cost to support it. Six municipalities on the western side of the province of Bologna were analysed. Waste water collection is managed by the municipal councils and treatment is carried out in plants managed by a service company. Waste water collection was analysed by compiling a mass balance of the sewer system serving the six municipalities, including construction materials and sand for laying the pipelines. Emergy analysis of the water treatment plants was also carried out. The results show that the great quantity of emergy required to treat a gram of water is largely due to input of non renewable fossil fuels. As found in our previous analysis of the first part of the cycle, treatment is likewise characterised by high expenditure of non renewable resources, indicating a correlation with energy flows.

Conservation of Natural Resources↗
PubMed2003

[Photooxidation characteristics of super-hybrid rice "Liangyoupeijiu" and its parents].

With comparison of the differences of light absorption and active oxygen metabolism between super-hybrid rice "Liangyoupeijiu" and its parents, this paper provided a physiological foundation of matching and grouping for cultivating anti-photooxidized hybrid rice. TPS-photosynthetic system and FMS2-fluorescence (Hansatech, UK) were used to respectively determine the photosynthetic rate and the chlorophyll fluorescence in the rice leaves that had been processed in artificial photooxidization. Meanwhile, the contents of chlorophyll, protein and malonaldehydic acid (MDA) as well as the activation of superoxide dismutase (SOD) and peroxidase (POD) were determined. The results showed that the photosynthetic rate of "Liangyoupeijiu" was 2.4% lower than that of its female parent, and 23% higher than that of its male parent. After eight days anti-photooxidization process, its chlorophyll content was higher than that of its female parent by 33%, protein by 15%, initial photochemical efficiency by 30%, SOD by 32% and POD by 100%, while its photochemical quince coefficient was lower than that of its female parent by 9% and MDA by 50%. It showed that there was not much difference between the filial generation and its male parent. The super-hybrid rice "Liangyoupeijiu" was very efficient for solar energy utilization under the condition of photooxidization, and had outgrown its parents in the aspect of anti-photooxidization.

Chimera↗
PubMed2000

Molecular breeding of cellulolytic microbes, plants, and animals for biomass utilization.

Cellulosic materials are the major components of fibrous biomass produced as a result of photosynthesis and are considered as a reservoir of solar energy and organic materials. In order to cope with the problems of food and energy shortages expected in the near future, biotechnologists are encouraged to develop new technologies for the more effective utilization of the world's sustainable resources, i.e., biomass. One way is to engineer microorganisms and animals with the capability of digesting and utilizing cellulosic materials, and plants which can be easily degraded by cellulolytic enzymes. In this article, we summarize recent studies on the molecular breeding of cellulolytic organisms for biomass utilization along with some considerations regarding cellulolytic enzymes.

Journal Article↗
PubMed2006

The structure, functions and degradation of pigment-binding proteins of photosystem II.

Eleven proteins belonging to photosystem II (PSII) bind photosynthetic pigments in the form of thylakoid membrane-associated pigment-protein complexes. Five of them (PsbA, PsbB, PsbC, PsbD and PsbS) are assigned to PSII core complex while the remaining six (Lhcb1, Lhcb2, Lhcb3, Lhcb4, Lhcb5 and Lhcb6) constitute, along with their pigments, functional complexes situated more distantly with regard to P680 - the photochemical center of PSII. The main function of the pigment-binding proteins is to harvest solar energy and deliver it, in the form of excitation energy, ultimately to P680 although individual pigment-proteins may be engaged in other photosynthesis-related processes as well. The aim of this review is to present the current state of knowledge regarding the structure, functions and degradation of this family of proteins.

Carrier Proteins↗
PubMed2006

[Genetic control of hydrogen metabolism in cyanobacteria].

The development of methods for the use of phototrophic cyanobacteria as producers of molecular hydrogen via bioconversion of solar energy is a promising filed of hydrogen energetics. Artificial optimization of hydrogen formation and release is based on studying the genetic control of hydrogen metabolism and the use of genetic approaches for obtaining efficient producer strains. Data on genes coding for the hydrogenases that are responsible for hydrogen uptake and production in cyanobacteria are summarized. Bioinformatic methods have been used to construct the scheme of the hydrogen metabolism gene network of nitrogen-fixing heterocyst cyanobacteria. The possible approaches to constructing the cyanobacterium strains producing molecular hydrogen that would be promising for photobiotechnology by mutagenesis and genetic engineering methods are discussed in terms of this model and analysis of the data on hydrogen-producing mutants.

Bacterial Proteins↗
PubMedDate not supplied

[Cyclical changes in the number of Ixodes persulcatus in Udmurtia].

Analysis involving autocorrelation functions indicated the presence of cyclic components in the changes in I. persulcatus population as well as in certain climatic parameters. Three orders of cycles are distinguished, their mean duration comprising 5.5; 11.1 and 22.2 years. High number peaks of I. persulcatus repeated with a mean period of 22 years in 1938-1942, 1959-1964 and 1983-1986, coinciding with the periods of solar energy decline in odd 11-year cycles. According to the established regularity, the next considerable rise in I. persulcatus number should be expected in 2003-2009 with a peak in 2004-2006.

Animals↗
PubMedDate not supplied

[Changes in medical indicators during heliogeophysical disturbances].

Influence of heliogeophysical factors on medical indexes is studied. Relationship between changes of these indexes and solar flares, magnetic and ionospheric storms is analyzed. Possibility of forecasting the biotropic effects by using the starting of heliogeophysical events as predictions is showed. Comparisons between calculations and experimental data are provided. Reasonable agreement was obtained.

Electromagnetic Fields↗
PubMed1995

Photosensitivity reactions: a case report involving NSAIDs.

Photosensitivity reactions associated with the use of prescription or over-the-counter drugs may be classified as phototoxic (caused by potentiation of solar energy by a drug) or photoallergic (in which the combination of a photosensitizing agent and light evokes a true cell-mediated hypersensitivity response). A case of a photoallergic response related to the use of piroxicam is included to illustrate the presentation and management of photosensitivity reactions to nonsteroidal anti-inflammatory drugs.

Adult↗
PubMed1998

Effects of solar radiation, dietary energy, and time of feeding on thermoregulatory responses and energy balance in cattle in a hot environment.

Ten growing heifers were either exposed to or protected from solar radiation, offered a diet of either high (H) or low (L) ME, and fed either in the morning or afternoon during a hot summer. Heifers that consumed the H diet had a greater water intake, DMI, metabolizable energy intake, energy expenditure, and retained energy than heifers that consumed the L diet. Solar radiation did not have an effect on any of these variables. Furthermore, dietary energy and time of measurement had an effect on rectal temperature (Tr), respiration rate (RR), heart rate (HR), and rate of oxygen uptake (VO2); solar radiation had an effect on Tr and RR but not on HR and VO2; and time of feeding had an effect only on VO2. Heifers coped with greater heat loads by increasing RR and the difference in Tr between morning and afternoon. It seems that a lowered body temperature in the morning is a physiological mechanism used by animals to prepare for the heat load that develops during the day. Heat production (HP) and HR throughout the day were affected mainly by the time of feeding and not by the environmental heat load. Feeding in the afternoon increased HP in the cooler hours of the day when heat losses from the animal through conduction and radiation were more efficient. With a pending high heat load situation, reducing feed quality and(or) changing the time of feeding to the late afternoon could be beneficial to the animals in reducing their heat loads.

Animals↗
PubMed1979

Solar-driven chemical energy source for a Martian biota.

Microorganisms deep in the Martian soil could derive energy indirectly from the sun via chemical reactions involving atmospheric products of the solar ultraviolet flux. The Viking discovery of a chemically uniform regolith which, though poor in organics, is rich in sulfur-containing compounds suggests reaction sequences in which sulfur is recycled through reduced and oxidized states by biologically catalyzed reactions with photochemically-produced atmospheric constituents. One candidate reaction, reduction of soil ssufate minerals by molecular hydrogen, is already exploited on earth by bacteria of the ubiquitous and tenacious Desulfovibrio genus.

Desulfovibrio↗