Showing papers by "University of Oviedo published in 1995"
TL;DR: In this article, a comparative study of the sorption of phenol and p-chlorophenol from water has been performed using novel samples prepared by carbonisation and subsequent activation of straw and used rubber typres as well as conventional activated carbons based on coal, coconut shell and wood.
279 citations
TL;DR: The results of several studies are reviewed and the evidence suggests that, if they are to account for the data, experience-based parsers must draw upon records or representations that capture statistical regularities beyond the lexical level.
Abstract: Several current models of human parsing maintain that initial structural decisions are influenced (or tuned) by the listener's or reader's prior contact with language. The precise workings of these models depend upon the “grain,” or level of detail, at which previous exposures to language are analyzed and used to influence parsing decisions. Some models are premised upon the use of fine-grained records (such as lexical cooccurrence statistics). Others use coarser measures. The present paper considers the viability of models based exclusively on the use of fine-grained lexical records. The results of several studies are reviewed and the evidence suggests that, if they are to account for the data, experience-based parsers must draw upon records or representations that capture statistical regularities beyond the lexical level. This poses problems for several parsing models in the literature.
274 citations
TL;DR: It is observed that cyst forma‐tion can be induced by various monoamine oxidase inhibitors and protonophores, that 5MT dramatically stimulates H‐dependent bioluminescence and leads to a decrease of cytoplasmic pH, as shown by measurements of dicyanohydroquinone fluorescence.
Abstract: Melatonin is widely abundant in many eukaryotic taxa, including vari-ous animal phyla, angiosperms, and unicells. In the bioluminescent dinoflagellate Gonyaulax polyedra, melatonin is produced in concentrations sometimes exceed-ing those found in the pineal gland, exhibits a circadian rhythm with a pro-nounced nocturnal maximum, and mimics the short-day response of asexual encystment. Even more efficient as a cyst inducer is 5-methoxytryptamine (5MT), which is also periodically formed in Gonyaulax. In this unicell, the photoperiodic signal-transduction pathway presumably involves melatonin formation, its deace-tylation to 5MT, 5MT-dependent transfer of protons from an acidic vacuole, and cytoplasmic acidification. According to this concept, we observe that cyst forma-tion can be induced by various monoamine oxidase inhibitors and protonophores, that 5MT dramatically stimulates H+-dependent bioluminescence and leads to a decrease of cytoplasmic pH, as shown by measurements of dicyanohydroquinone fluorescence. Cellular components from Gonyaulax catalyze the photooxidation of melatonin. Its property of being easily destroyed by light in the presence of cel-lular catalysts may have been the reason that many organisms have developed mechanisms utilizing this indoleamine as a mediator of darkness. Photooxidative reactions of melatonin, as studied with crude Gonyaulax extracts and, more in de-tail, with protoporphyrin IX as a catalyst, lead to the formation of N1 -acetyl-N -formyl-5-methoxykynuramine (AFMK) as one of the main products. Photochemical mechanisms involve interactions with a photooxidant cation radi-cal leading to the formation of a melatonyl cation radical, which subsequently combines with a superoxide anion. Photooxidation of melatonin represents one of several possibilities of a more general, biologically highly important property of this indoleamine to act as an extremely efficient radical scavenger, including its feature of terminating radical reaction chains by a final combination with the su-peroxide anion. Trapping of free radicals may reflect the primary and evolutionar-ily most ancient role of melatonin in living beings.
265 citations
TL;DR: In this article, the fouling and retention of four different nanofiltration membranes (NF40, NTR-7450, NM-7410 and NM-7250) were followed using different model substances, and it could be seen that multivalent salts were retained better than small organic substances.
259 citations
TL;DR: Melatonin should be considered as a component of the antioxidative defense system in this avian species because of its ability to stimulate glutathione peroxidase activity, and reduce the generation of highly toxic hydroxyl radicals by metabolizing its precursor, hydrogen peroxide.
Abstract: The pineal hormone melatonin has been shown to directly scavenge free radicals and to stimulate, in the mammalian brain, at least one enzyme, glutathione peroxidase, which reduces free radical generation In the present studies, we examined the effect of melatonin on glutathione peroxidase activity in several tissues of an avian species Melatonin (500 micrograms/kg), when injected into chicks, increased glutathione peroxidase activity within 90 min in every tissue examined Tissue melatonin levels, measured by radioimmunoassay, also increased following its peripheral administration Depending on the tissue, the measured increases in melatonin varied from 75% to 1,300% over the control values The melatonin-induced increases in glutathione peroxidase activity varied with the tissue and were between 22% and 134% These percentage increases in glutathione peroxidase activity were directly correlated with tissue melatonin content These results suggest that melatonin induces the activity of the detoxifying enzyme, glutathione peroxidase, in several tissues in the chick The findings also suggest that melatonin would reduce the generation of highly toxic hydroxyl radicals by metabolizing its precursor, hydrogen peroxide Because of this ability to stimulate glutathione peroxidase activity, melatonin should be considered as a component of the antioxidative defense system in this avian species
208 citations
TL;DR: The relationship between supersaturation at the point of crystallization and the rate at which supersaturation increases has been studied from nucleation experiments on barite BaSO4, strontianite SrCO3, witherite BaCO3 and gypsum CaSO4.2H2O as discussed by the authors.
Abstract: The relationship between the supersaturation at the point of crystallization and the rate at which supersaturation increases has been studied from nucleation experiments on barite BaSO4, strontianite SrCO3, witherite BaCO3 and gypsum CaSO4.2H2O. The crystallization experiments have been carried out by the counter-diifusion of cations and anions through a column of porous silica gel transport medium. Nucleation is suppressed in a finely-porous medium resulting in very high values of supersaturation before crystallization from the solution begins. This threshold supersaturation for nucleation depends on the solubility of the salt, the porosity of the medium and the supersaturation rate. Nucleation inhibitors were used to extend the range of supersaturation attainable. In all cases the experimental data fits the general expression: rate of change of supersaturation ∝ (threshold supersaturation)m. These results are compared to previous work from the field of chemical engineering on the relationship between supersaturation, volume and cooling rate in aqueous salt solutions. These experiments have important implications to supersaturation in natural fluids and subsequent crystallization in relation to geological problems including crystallization in low temperature sedimentary environments and fluid-rock ratios in hydrothermal mineral deposits.
174 citations
TL;DR: Genetic analysis potentially provides the only reliable method to unambiguously determine their species identity, but from a practical point of view, the procedure chosen must be fast, extremely robust, and be able to utilize tiny quantities of any tissue.
Abstract: The members of the salmonid family form perhaps the most economically important group of the world’s fish species. In Europe the most important species employed in fish farming are the introduced rainbow trout (Oncorhynchus mykiss) and the Atlantic salmon (Salmo salnr), whereas interest in the brown trout (Salmo trufta) is based on its ecological diversity and sport fishing. These two Salmo species are very difficult to distinguish using morphological characters, not only during their first months of life (eggs and alevins) but also at the returning adult stage. Isoenzyme genetic analysis, which has usually been used for their identification, has often demonstrated that anglers have confused adults of brown trout with Atlantic salmon, or with salmon x trout hybrids (Leaniz & Verspoor 1989). Caution must therefore be taken in enhancement programmes since the artificial spawning of adults caught in the river could lead to restocking with salmon x trout hybrids. Another area of interest is the identification of manufactured products of these species (i.e. smoked). Genetic analysis potentially provides the only reliable method to unambiguously determine their species identity. In addition, the genetic marker employed should be a nuclear marker if interspe cific hybrids among these species have to be recognized. From a practical point of view, the procedure chosen must be fast, extremely robust, and be able to utilize tiny quantities of any tissue. This last requirement excludes most isoenzyme techniques. At present, PCR-based methodologies constitute the most reliable techniques available for this purpose. Most of these approaches are, however, based on the use of conserved mitochondria1 DNA primers (for the cytochrome b gene) and sequencing of the amplified fragment (Paabo et al. 1989; Bartlett h Davidson 1992). Instead, we have focused on the 5s
160 citations
TL;DR: The transcriptional regulation of the HXK1, HxK2 and GLK1 genes is described in the hope of revealing differences in the steady‐state levels of mRNA associated with a particular carbon source used in the culture medium.
Abstract: In Saccharomyces cerevisiae, the transcriptional regulation of most glycolytic genes has been extensively studied. By contrast, little is known about the transcriptional control of the three glucose-phosphorylating enzymes, although this catalytic reaction has an important role in the regulation of cell metabolism. In this paper, we describe the transcriptional regulation of the HXK1, HXK2 and GLK1 genes in the hope of revealing differences in the steady-state levels of mRNA associated with a particular carbon source used in the culture medium. Our results provide evidence supporting a differential expression of the three genes depending on the carbon source used for growth. We have also studied the induction and repression kinetics of mRNA expression for the HXK1, HXK2 and GLK1 genes.
144 citations
TL;DR: Investigative efforts should be directed to the possible role of melatonin in inhibiting cell death in tissues other that the thymus, since apoptosis is a possible mechanism involved in neuronal death shown in several neurodegenerative diseases such as Parkinson or Alzheimer's diseases.
Abstract: Recently, melatonin was found to be the most potent physiological free radical scavenger known to date. In this work, we attempted to define the role this neurohormone plays in the regulation of apoptosis, since the effect of bcl-2, the main gene implicated in its inhibition, acts via an antioxidant mechanism. We investigated the role of melatonin in cell death of thymus, a well known model for the study of apoptosis. Two sets of experiments were carried out : in vivo experiments, performed with Wistar rats, and in vitro experiments, performed with primary cultures of young Wistar rat thymocytes treated with glucocorticoids in order to induce apoptosis. Morphometrical studies in semithin sections of thymus and analysis of DNA fragmentation by gel electrophoresis show that physiological apoptosis occurring in thymus of 65 days old rats, is prevented by the daily administration of melatonin beginning when the rats were 25 days old. Also, we found that at a concentration of 10 -7 M, melatonin decreases by 35% the percentage of apoptotic cells induced by glucocorticoids in cultured thymocytes of 25 day old rats. 10 -9 M melatonin decreases cell death by 20%. Finally, melatonin at 10 -11 M did not have any effect. Several hypothesis are discussed to explain this effect : direct interaction of melatonin with glucocorticoid receptors in the thymus ; induction of interleukin-4 release ; direct genomic action modulating the expression of apoptosis-inhibiting genes ; an effect on nitric oxide synthase ; and finally, the antioxidant action of melatonin. Since apoptosis is a possible mechanism involved in neuronal death shown in several neurodegenerative diseases such as Parkinson or Alzheimer's diseases, investigative efforts should be directed to the possible role of melatonin in inhibiting cell death in tissues other that the thymus. Melatonin might be a potent therapeutic agent in some of these conditions.
130 citations
TL;DR: A role for ApoD in the mobilisation of Arachidonic acid, and hence prostaglandin synthesis is suggested, as well as a role for cholesterol nor any of the other prostanoid molecules examined had measurable affinity.
126 citations
TL;DR: The Santiago Schists are located in the Basal Unit of the Ordenes Complex, one of the allochthonous complexes outcropping in the inner part of the Hercynian Belt in the north-west of the Iberian Peninsula.
Abstract: The Santiago Schists are located in the Basal Unit of the Ordenes Complex, one of the allochthonous complexes outcropping in the inner part of the Hercynian Belt in the north-west of the Iberian Peninsula. Their tectonothermal evolution is characterized by the development of an eo-Hercynian metamorphic episode (c. 374 Ma) of high-P, low- to intermediate-T. The mineral assemblage of the high-P episode is preserved as a very thin Si= S1 foliation included in albite porphyroblasts, being composed of: albite + garnet-I + white mica-1 + chlorite-1 + epidote + quartz + rutile ± ilmenite. The equilibrium conditions for this mineral assemblage have been estimated by means of different thermobarometers at 495 ± 10 °C and 14.7 ± 0.7 kbar (probably minimum pressure). The later evolution (syn-D2) of the schists defines a decompressive and slightly prograde P-T path which reached its thermal peak at c. 525 ± 10 °C and 7 kbar. Decompression of the unit occurred contemporaneously with an inversion of the metamorphic gradient, so that the zones of garnet-II, biotite (with an upper subzone with chloritoid) and staurolite developed from bottom to top of the formation.
The estimated P-T path for the Santiago Schists suggests that the Basal Unit, probably a fragment of the Gondwana continental margin, was uplifted immediately after its subduction at the beginning of the Hercynian Orogeny. It also suggests that the greater part of the unroofing history of the unit took place in a context of ductile extension, probably related to the continued subduction of the Gondwana continental margin and the contemporaneous development of compensatory extension above it. The inverted metamorphic gradient seems related to conductive heat transferred from a zone of the mantle wedge above the subducted continental margin, when it came into contact with the upper parts of the schists along a detachment, probably of extensional character.
The general metamorphic evolution of the Santiago Schists, with the development of high-P assemblages with garnet prior to decompressive and prograde parageneses with biotite, is unusual in the context of the European Hercynian Belt, and shows a close similarity to the tectonothermal evolution of several high-P, low- to intermediate-T circum-Pacific belts.
TL;DR: Functional analysis of the oleB gene showed that either the first or the second half of the gene containing only one ATP‐binding domain was sufficient to confer resistance to oleandomycin, and it was shown that a Streptomyces albus strain, containing both a glycosyltransferase and the OleB protein, was capable ofglycosylating ole fandomycin and secreting the inactive Glycosylated molecule.
Abstract: A 3.2 kb Sstl-Sphl DNA fragment of Streptomyces antibioticus, an oleandomycin producer, conferring resistance to oleandomycin was sequenced and found to contain an open reading frame of 1710 bp (oleB). Its deduced gene product (OleB) showed a high degree of similarity with other proteins belonging to the ABC-transporter superfamily including the gene product of another oleandomycin-resistance gene (OleC). The OleB protein contains two ATP-binding domains, each of approximately 200 amino acids in length, and no hydrophobic transmembrane regions. Functional analysis of the oleB gene was carried out by deleting specific regions of the gene and assaying for oleandomycin resistance. These experiments showed that either the first or the second half of the gene containing only one ATP-binding domain was sufficient to confer resistance to oleandomycin. The gene oleB was expressed in Escherichia coli fused to a maltose-binding protein (MBP) using the pMal-c2 vector. The MBP-OleB hybrid protein was purified by affinity chromatography on an amylose resin and polyclonal antibodies were raised against the fusion protein. These were used to monitor the biosynthesis and physical location of OleB during growth. By Western analysis, the OleB protein was detected both in the soluble and in the membrane fraction and its synthesis paralleled oleandomycin biosynthesis. It was also shown that a Streptomyces albus strain, containing both a glycosyltransferase (OleD) able to inactivate oleandomycin and the OleB protein, was capable of glycosylating oleandomycin and secreting the inactive glycosylated molecule. It is proposed that OleB constitutes the secretion system by which oleandomycin or its inactive glycosylated form could be secreted by S. antibioticus.
TL;DR: In this paper, a new adsorptive stripping voltammetric method (ASV) for the determination of colloidal gold is investigated, which is based on the previous metal accumulation onto a carbon paste surface electrode followed by an oxidation process of the adsorved colloid to an Au(III)-chloro complex which is then electrochemically reduced to Au(0).
TL;DR: In this paper, the preparation, spectroscopic, magnetic properties, and crystal structure of [Cu(stzxpy) 3 Cl] (stz − stands for the deprotonated form of sulfathiazole, 4-amino-N-2-thiazolylbencenosulfonamide) are reported.
TL;DR: Between-population gene flow was estimated in neighbouring freshwater and anadromous Salmo trutta populations from Asturias, Northern Spain and the strength of the homing orientation of migratory individuals (sea trout) is discussed.
Abstract: Between-population gene flow was estimated in neighbouring freshwater and anadromous Salmo trutta populations from Asturias, Northern Spain. Populations from the same drainage showed a high mean level of gene flow. Gene flow was also found between populations from different drainages and was negatively related to the distance between river mouths. The strength of the homing orientation of migratory individuals (sea trout) is discussed.
TL;DR: The oleP gene was expressed in Escherichia coli as a fusion protein to a maltose-binding protein and it was observed that the synthesis of the cytochrome P450 was in parallel to that of oleandomycin.
Abstract: A cosmid clone from an oleandomycin producer, Streptomyces antibioticus, contains a large open reading frame encoding a type I polyketide synthase subunit and an oleandomycin resistance gene (oleB). Sequencing of a 1.4-kb DNA fragment adjacent to oleB revealed the existence of an open reading frame (oleP) encoding a protein similar to several cytochrome P450 monooxygenases from different sources, including the products of the eryF and eryK genes from Saccharopolyspora erythraea that participate in erythromycin biosynthesis. The oleP gene was expressed in Escherichia coli as a fusion protein to a maltose-binding protein. Using polyclonal antibodies against this fusion protein it was observed that the synthesis of the cytochrome P450 was in parallel to that of oleandomycin. The cytochrome P450 encoded by the oleP gene could be responsible for the epoxidation of carbon 8 of the oleandomycin lactone ring.
TL;DR: The result for silicon suggest that it seems to be unspecifically adsorbed to several serum proteins and its speciation is not affected by the presence of DFO.
Abstract: Speciation of aluminium and silicon in serum was studied by a reliable and sensitive high-performance liquid chromatographic–electrothermal atomic absorption spectrometric (HPLC–ETAAS) hybrid method, based on the use of a polymeric anion-exchange column (Protein-Pak DEAE-5PW). This polymer-based column minimizes the risk of aluminium losses and of silicon contamination from the column during separation. The results obtained were compared with the results of previous studies carried out using different, complementary techniques including ultramicrofiltration, gel filtration and a silica-based column for HPLC. In order to ascertain which protein(s) of serum actually bind(s) aluminium, gel electrophoresis was employed for the further separation of the column fractions obtained by HPLC and aluminium was determined in separate aliquots of the same fractions. From all the experiments, it appears that transferrin (Tf) is the only serum protein that binds aluminium and it contains about 90% of total serum aluminium. It was also confirmed that in the presence of desferrioxamine (DFO), aluminium is partly displaced from its complex with transferrin to a low molecular mass Al–DFO complex. Aluminium citrate seems to be the main low molecular mass aluminium species in serum, amounting to about 12 ± 5% of the total aluminium in an aluminium-loaded serum sample. The proposed speciation procedure permits the simultaneous identification and determination of three aluminium species in metal-spiked serum (Al–Tf, Al–DFO and Al–citrate). The results for silicon suggest that it seems to be unspecifically adsorbed to several serum proteins and its speciation is not affected by the presence of DFO. Moreover, no evidence was found to confirm possible interrelations between aluminium and silicon species in serum to justify significant aluminosilicate formation in human serum.
TL;DR: In this article, an experimental evidence for the existence of orbitally excited B meson states is presented in an analysis of the Bπ and B∗π distribution of View the MathML source using Z0 decay data taken with the DELPHI detector at LEP.
TL;DR: The chiral stationary phase for high-performance liquid chromatography shows good chiral recognition ability in both the liquid phase and the solid-state phase.
Abstract: Original article can be found at: http://prola.aps.org/vtoc/PRA/v52 Copyright American Physical Society. DOI: 10.1103/PhysRevA.52.R2497 [Full text of this article is not available in the UHRA]
18 Jun 1995
TL;DR: In this paper, a half-bridge DC/DC power converter with complementary control and self-driven synchronous rectification is described, which is shown to have high efficiency for low output voltage, soft-switching for primary and secondary switches and very small output filter.
Abstract: A half-bridge DC/DC power converter with complementary control and self driven synchronous rectification is described in this paper. Zero voltage switching is analyzed taking into account the effect of the parasitic capacitances of the synchronous rectifiers of the secondary side. The main advantages of this power converter, which are high efficiency for low output voltage, soft-switching for primary and secondary switches and very small output filter, are shown in an actual prototype. >
TL;DR: In this article, the influence in these reactions of several factors (concentration of reagents, molar ratio P:Ti in the reaction mixture, temperature and reaction time) was studied.
TL;DR: It is suggested that a low sodium diet may play a key-role in the treatment of pediatric patients with cystinuria and confirm that elimination of cystine is highly influenced by sodium intake in Cystinuric children.
Abstract: Restriction of sodium intake has been shown to decrease urinary elimination of cystine in adult subjects with cystinuria. This simple therapeutic recommendation may be particularly useful in pediatric patients whose compliance with high fluid ingestion and repeated doses of alkali is usually poor. We studied the effect of sodium intake in 5 cystinuric children (3 males) aged 5.9-9.3 years. Urinary excretion of cystine (means +/- SD) was determined at the end of two sequential 1-week periods in which sodium content of diet was modified. Reduction of sodium intake brought about significant decreases in natriuresis (6.0 +/- 2.1 vs. 1.5 +/- 0.5 mEq/kg/day, p < 0.03) and urine cystine concentration (328.0 +/- 190.7 vs. 14.1 +/- 7.4 mg/l, p < 0.02) while urine volume output remained unchanged (58.0 +/- 36.0 vs. 70.3 +/- 33.0 ml/kg/day). These findings confirm that elimination of cystine is highly influenced by sodium intake in cystinuric children and suggest that a low sodium diet may play a key-role in the treatment of pediatric patients with cystinuria.
TL;DR: A recombinant baculovirus containing the gene encoding the structural protein VP60 from the Spanish field isolate AST/89 of rabbit haemorrhagic disease virus was able to elicit a protective response in rabbits against a nasal challenge with 100 LD50 of RHDV.
Journal Article•
TL;DR: The gene coding for human collagenase-3 (CLG3), a recently described matrix metalloproteinase produced by breast carcinomas, has been localized by fluorescence in situ hybridization on chromosome 11q22.3.
TL;DR: A region-specific distribution in the pattern of photoreceptor degeneration is identified, with the dorsal retina showing markedly less photorecept degeneration than the ventral retina.
TL;DR: In this article, a 3D visualization of the microfractographic network, crack connectivity, automatic evaluation of direction and slope of fissures, and the relations between potentially water-conducting open fissure, and other rock-forming minerals provide a security factor in their definitive storage in rock masses.
Abstract: SUMMARY
Scanning laser microscopy, in the confocal mode (CSLM) has been applied to a granitic rock to characterize its fissure space. The technique provides a unique three-dimensional picture of the rock microfractography. CSLM is unique in observing fine details of the fractographic network (connectivity, tortuosity, etc.), its geometry and its relation to other rock-forming components.
The fractographic images with standard fluorescence microscopy are compared with those obtained with CSLM. The examples presented emphasize the advantages of CSLM: three-dimensional visualization of the microfractographic network, crack connectivity, automatic evaluation of direction and slope of fissures.
These studies are related to the migration of radionuclides in the geosphere. The relations between potentially water-conducting open fissures, and the rock-forming minerals provide a means of modelling the ‘radionuclide retardation mechanism’, a security factor in their definitive storage in rock masses.
TL;DR: The hexachlorocyclotriphosphazene [N 3 P 3 Cl 6 ] reacts with 2-hydroxypyridine (HOC 5 H 4 N-2) in acetone in the presence of K 2 CO 3, to give the hexasubstituted products N 3 P3 (OC 5H 4 N -2) 6 ( 1 ) and N 3P 3 (OC 4 H 4 NE 4 ) 6 ( 2 ). The structure of both compounds was determined by X-ray diffraction.
TL;DR: Two possible mechanisms of resistance have been detected: (i) impermeability to exogenous fosfomycin, even in the presence of sugar phosphate uptake inducers, and (ii) antibiotic phosphorylation.
Abstract: Pseudomonas syringe PB-5123, a producer of fosfomycin, is resistant to high concentrations of the antibiotic. Two possible mechanisms of resistance have been detected: (i) impermeability to exogenous fosfomycin, even in the presence of sugar phosphate uptake inducers, and (ii) antibiotic phosphorylation. The gene responsible for this last activity, fosC, encodes a ca. 19,000-Da protein and is immediately followed by a second open reading frame, which shows sequence similarities to glutathione S-transferases. FosC uses ATP as a cosubstrate in an inactivation reaction that can be reversed with alkaline phosphatase. Other nucleotide triphosphates cannot be substituted for ATP in this reaction. No relationship between fosC and the previously described genes of fosfomycin resistance was found.
TL;DR: Melatonin, which is able to enter all tissues and all compartments of the cell, acts in a highly pleiotropic fashion and is a powerful radical scavenger, terminating free radical reaction chains initiated by photooxidants, hydroxyl or peroxyl radicals.
Abstract: Melatonin, which is able to enter all tissues and all compartments of the cell, acts in a highly pleiotropic fashion. Some melatonin effects are mediated by membrane receptors, others are receptor independent. Melatonin is produced in the pineal gland and various extrapineal organs of vertebrates, but is also found in invertebrates, angiosperms, and unicells. In mammals, melatonin elicits various secondary humoral responses, e.g., in the immune system via interleukin-4 and other cytokines and in the brain by modulation of NO formation. Melatonin is also a powerful radical scavenger, terminating free radical reaction chains initiated by photooxidants, hydroxyl or peroxyl radicals. The protective potency of this indoleamine is demonstrated by various experiments.