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PubMed2004

[Effects of tea polyphenols and tea pigments on telomerase activity of HepG2 cells].

OBJECTIVE: This study is to investigate the effect of tea polyphenols and tea pigments on telomerase activity of human liver cancer cell line, HepG2 cells. METHODS: TRAP-PCR-ELISA was applied to investigate the telomerase activity. RESULTS: Telomerase was positive in tea polyphenols treated groups, tea pigments treated groups and blank control group. Telomerase activities (A(450 approximately 690) values) were 1.56 and 1.46 in 50 mg/L and 100 mg/L tea polyphenols-treated groups, 1.55 and 1.49 in 50 mg/L and 100 mg/L tea pigments-treated groups, respectively. The results showed that telomerase activity was significantly inhibited by tea polyphenols and tea pigments treatment as compared with the blank control group (A(450 approximately 690) = 2.11). CONCLUSIONS: Tea polyphenols and tea pigments could significantly inhibit telomerase activity of HepG2 cells, and telomerase activity may be a useful biomarker for cancer chemoprevention.

Biomarkers, Tumor↗
PubMed2004

[A protanomalous female whose genotype of red/green visual pigment genes was determined by molecular analysis of her family members].

PURPOSE: To determine X-linked red/green visual pigment gene arrays of a female proband with protan deficiency. METHODS: We examined a brother and both parents as well as the proband. Severity, severe or mild form, of color vision deficiency was estimated with either failure or passing of the Farnsworth Panel D-15 test. Diagnosis of either anomalous trichromacy or dichromacy was performed using a Nagel Type I anomaloscope. Genotypes of red/green visual pigment genes were determined by quantitative polymerase chain reaction-single strand conformation polymorphism analysis. RESULTS: Color vision tests revealed that the proband, her brother, her father, and her mother had protanomaly(mild form), protanopia, protanomaly(severe form), and normal color vision, respectively. In analysis of gene arrays, the brother had a red-green hybrid gene(R1G2, Ser 180) and three green visual pigment genes, while the father had a red-green hybrid gene(R4G5, Ser 180) and a green visual pigment gene. CONCLUSIONS: It is impossible to directly determine each paternal or maternal X-linked red/green pigment gene array in the female proband. Molecular analysis of the family members revealed that the proband was a compound heterozygote for two R1 G2 and R4G5 hybrid genes encoding photopigments with different absorption maxima.

Chromosomes, Human, X↗
PubMed2004

Decomposition dynamic of higher plant pigments by HPLC analysis.

The fate of the litter of dominant vegetation(willows and reeds) is one of the aspects studied in the frame of the project "Onderzoek Milieu Effecten Sigmaplan". One of the questions to be considered is how long the litter stays within the estuary. In this paper, the time the leaf litter (Salix triandra and Phragmites australis) stayed in the Schelde estuary was studied by using plant pigment as biomarkers with HPLC application. After analyzing the original data from the incubation experiment described by Dubuison and Geers (1999), the decomposition dynamics patterns of pigments were analyzed and described, and these decomposition dynamics patterns were used as calibration patterns. By using Spearman Rank Order Correlation, the calibration patterns of the pigments which were significant (p < 0.05) were grouped. In this way, several groups of the calibration patterns of pigment decomposition were achieved. The presence or absence of these groups of pigments (whether they can be detected or not from HPLC) was shown to be useful in determining the time the litter has stayed in the water. Combining data of DW and POC, more precise timing can be obtained.

Chromatography, High Pressure Liquid↗
PubMed2005

Adenomatoid odontogenic tumour: a clinico-pathological analysis and melanin pigmentation study of 31 Nigerian cases.

AIM: Clinicopathological analysis and melanin pigmentation occurrence in adenomatoid odontogenic tumour (AOT) diagnosed and managed at the Lagos University Teaching Hospital during a 29- year period. METHODS: Records of 31 cases were reviewed and standard epidemiological data were obtained. Haematoxylin and eosin stained slides of the cases were retrieved and reevaluated for reconfirmation of diagnosis. Celloidinised paraffin sections of all cases were subjected to Fontana Masson stain and melanin bleach to assess presence of melanin pigment. RESULTS: AOT is an uncommon type of odontogenic tumour that is commoner in younger age group (8-35 years) with site predilection for the anterior maxilla (64.5%). Occurrence of melanin pigment in AOT was very rare as there was positive melanin pigmentation in only one case in spite of the fact that the study was carried out in a predominantly Black population. CONCLUSION: Pattern of occurrence of AOT observed in this Lagos series is similar to previous studies in the scientific literature. Melanin pigmentation is rarely demonstrated in AOT even in a predominantly Black population.

Adolescent↗
PubMed1991

Antagonistic effect of amiloride on alpha-2 adrenoceptor-mediated pigment aggregation: pharmacological heterogeneity between B-HT 920 and noradrenaline.

Pigment aggregation in melanophores from the cuckoo wrasse (Labrus ossifagus L.) has previously been shown to be mediated by alpha-2 adrenoceptors. In the present investigation, the effect of amiloride on pigment aggregation induced by noradrenaline and B-HT 920 was studied. Amiloride caused a parallel shift to the right in concentration-response curves for 5-allyl-2-amino-5,6,7,8-tetrahydrothiazolo-[4,5-d]azepine-dihyd roc hloride: (B-HT 920), with no change in the maximal response, indicating simple competitive inhibition. Subsequent Schild plot analysis gave a straight line with a slope of almost unity (0.95) and a KB of 5 x 10(-6) M. In contrast to the effect of amiloride on B-HT 920-induced pigment aggregation, only a very high concentration of amiloride (1 x 10(3) M) inhibited the corresponding effect of noradrenaline. Na+/H+ exchange has been suggested as a possible mechanism for alpha-2 adrenoceptors, and the amiloride analogs 5-(N,N-dimethyl)amiloride and 5-(N,N-hexamethylene)amiloride are known to be more specific than amiloride itself in this respect. However, these analogs inhibited the effect of B-HT 920 significantly less effectively than amiloride. Furthermore, manipulating the extracellular pH between 6.8 and 7.8 did not affect the concentration response curves of B-HT 920. Neither did the prostanoid pathway inhibitors, quinacrine or indomethacin, inhibit the pigment-aggregating effect of B-HT 920. The present results suggest that amiloride competes with B-HT 920 as receptor antagonist, and that Na+/H+ exchange is insignificant for the alpha-2 adrenoceptor-stimulated pigment aggregation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic alpha-Agonists↗
PubMed2006

Phylogenetic analysis of the Cardini group of Drosophila with respect to changes in pigmentation.

Phenotypic variability is the engine that drives future diversification with the expectation that polymorphic ancestors give rise to descendants harboring a subset of the ancestral variation. Here we examine evolutionary transitions from polymorphism to monomorphism in a visually striking New World radiation of fruit flies, the Drosophila cardini group. This group is distributed across the Americas and the Caribbean islands and exhibits a wide spectrum of abdominal pigmentation variation. Specifically, the D. dunni subgroup consists of Caribbean island endemics, each of which is monomorphic for its pigmentation pattern, with an interspecific cline of pigmentation across the islands. The D. cardini subgroup consists of American continental species with wide-ranging distributions and intraspecifically variable abdominal pigmentation. We determined the phylogeny of 18 species and subspecies using three nuclear and three mitochondrial regions analyzed with maximum parsimony, maximum likelihood, and Bayesian methods. The topology produced from a combined dataset exhibited high support values at all nodes, and differed from earlier phylogenetic hypotheses based on polytene chromosome inversion patterns and isozyme data. We find that the D. dunni subgroup species, with the exception of D. belladunni, are derived from a single source not of direct South American origin and their dispersal across the islands of the Caribbean does not follow a simple stepping-stone model. Morphological changes in pigmentation across the island species are incongruent with the colonization history of the group indicating that natural selection may have played a role in the determination of this character. Finally, we demonstrate that monomorphic species have arisen independently from polymorphic ancestors two to three times.

Animals↗
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↗
PubMed1990

[Familial cases of cutaneous myxomas and spotty pigmentation (Carney's complex)].

In 1985, Carney et al reported a complex of myxomas, spotty pigmentation, and endocrine overactivity and subsequently demonstrated dominant inheritance of the condition. The criteria for diagnosis of the complex is the presence of two or more of the following conditions: (1) cardiac myxoma, (2) cutaneous myxoma, (3) mammary myxoma, (4) spotty mucocutaneous pigmentation, (5) primary pigmented nodular adrenocortical disease (Cushing's syndrome), (6) testicular tumors (sexual precocity), (7) pituitary adenoma secreting growth hormone (acromegaly or gigantism). We encountered a family with an affected mother and daughter. Case 1 was a 43-year-old woman with multiple cutaneous myxomas, mammary myxomas and spotty mucocutaneous pigmentation. Case 2, the 19-year-old daughter of case 1 had multiple cutaneous myxomas and spotty cutaneous pigmentation. These two cases both met the criteria for the diagnosis of the complex. Our report is believed to be the first report on the complex in Japan.

Adult↗
PubMed1975

Chromatographic separation of pigments produced by Arthroderma benhamiae.

Variations in pigment production under different cultural conditions have limited the usefulness of pigmentation for identifying strains of Arthroderma benhamiae. If culture conditions are constant, pigmentation by individual strains is reproducible, and may be extracted and separated by thin layer chromatography. This allows recognition of pigment similarities which may be masked in whole colonies, thereby greatly enhancing the value of pigmentation in strain identification.

Acetone↗
PubMed1989

Pigment resembling atmospheric dust in Peyer's patches.

Terminal ileal pigmentation was observed during colonoscopy, in surgically resected specimens, and autopsy cases. Microscopically, black pigment was seen within macrophages in the lamina propria and submucosa, closely related to the Peyer's patches. Three ilia from autopsies with no macroscopic pigmentation showed deposits following digestion and X-ray microanalysis. X-ray microanalysis of tissue sections and digestates revealed a heterogenous population of particles. Approximately one third of the particles contained calcium and phosphorus and were considered endogenous. The rest of the particles were predominantly aluminum and magnesium-rich silicates, which were considered exogenous. Analysis of particulate extracted from lungs and ilea of four autopsy cases demonstrated remarkable similarities in composition. These findings suggest that the ileal deposits are derived from atmospheric dust. This pigment is believed to migrate into the Peyer's patches through the M cells of the follicle associated epithelium, although other mechanisms for pigment deposition cannot be ruled out.

Dust↗
PubMed1985

Ocular toxicity of beta-blockers and benzalkonium chloride in pigmented rabbits: electrophysiological and morphological studies.

Subconjunctival injection of 0.2 ml of the following solutions was carried out once a day for two weeks in the albino and pigmented rabbit: commercial 0.5% timolol or 1% befunolol ophthalmic solutions, both containing benzalkonium chloride, and also these drug solutions containing no preservative, ophthalmic base solutions containing benzalkonium chloride, physiological saline solution or phosphate buffer solution. One week after daily injections of the commercial drug solutions or base solutions with benzalkonium chloride, the electroretinogram (ERG) showed a marked reduction in the a- and b-wave amplitudes in the pigmented rabbit, but the ERG changes were slight in the albino rabbit. After two weeks of injections, histological studies of the pigmented rabbit eyes revealed retinal detachment, visual cell loss and atrophy of the retinal pigment epithelium and choroid; the changes in the albino rabbit eyes were minimal. Injections of the beta-blockers containing no benzalkonium resulted in no significant changes in the ERG or in the tissue structures of all rabbits. Injections of only physiological saline or phosphate buffer had no deleterious effects. Therefore, the ocular toxicity of the beta-blockers was thought to be minor and the toxic effects seen in this study were thought to be due to benzalkonium chloride, which possibly accumulates in the ocular pigments.

Adrenergic beta-Antagonists↗
PubMed1986

Regulation of pigment organelle translocation. I. Phosphorylation of the organelle-associated protein p57.

Treatment of goldfish xanthophores with adrenocorticotropin (ACTH) or cyclic AMP (cAMP) induces the centrifugal movement of their pigment organelles from the center of the cells. Using purified xanthophores pulse labeled with 32Pi, we have shown that the dispersion of the organelles is accompanied by the phosphorylation of a pair of polypeptides, termed p57. After fractionation on sucrose gradients, nearly all of the p57 is found associated with the pigment organelles. The phosphorylation induced by ACTH or cAMP apparently occurs at multiple sites on p57. The minimal effective doses of ACTH or cAMP required to induce full pigment dispersion also fully stimulate the phosphorylation of p57. Increased phosphorylation of p57 is detectable within a minute after stimulating the cells and appears to be near completion during the early phases of pigment dispersion. Upon withdrawal of ACTH, these events are reversed; the pigment organelles reaggregate toward the center of the cells and p57 is dephosphorylated. Again, dephosphorylation commences soon after ACTH is withdrawn and is complete before the organelles have completely reaggregated. These results suggest a novel mechanism for governing the movement of these organelles which acts on the organelles themselves through the phosphorylation and dephosphorylation of p57.

Adrenocorticotropic Hormone↗
PubMed1986

Niridazole-induced red/brown urine pigment is associated with increased urinary beta-glucuronidase excretion and a bladder site of formation.

Niridazole caused red/brown urine pigment in a man during treatment for Schistosoma mansoni infection. The urine pigment has been observed during niridazole treatment of schistosomiasis, but has not been documented during treatment of other diseases. Urinary beta-glucuronidase (EC 3.2.1.31) concentration increased proportionately to the amount of red/brown pigment in the urine. Concurrently, sterile pyuria developed. The duration of the time urine was in the bladder was directly related to the concentration of beta-glucuronidase and to the intensity of the red/brown urine color, there being much more in infrequently than in frequently voided urine specimens. Pigment development appears to occur in the bladder. The associated and possibly contributing components appear to be niridazole or one of its metabolites, beta-glucuronidase from the kidneys or from urinary granulocytes, and possibly a schistosomal factor. Given time, this combination generated the red/brown pigment.

Adult↗
PubMed1988

Black thyroid associated with minocycline therapy: histochemical and ultrastructural studies on the brown pigment.

The brown pigment found in the black thyroid, associated with minocycline therapy, was studied histochemically and ultrastructurally. The brown pigment was Fontana-Masson silver-positive, and was negative for iron, for autofluorescence under uv illumination, for periodic acid Schiff (PAS) and for acid-fast iodine peroxidase (AFIP) lipofuscin, and was bleached with potassium permanganate. The light and electron microscopic studies suggested that the pigment resembled melanin. Although the mechanism of the pigment deposition is not clear, a possible explanation may be that the pigment is related to direct oxidative degradation products of minocycline.

Aged↗
PubMed1986

Chick retinal pigment epithelium exhibits glutathione requiring prostaglandin D2 synthetase activity.

Prostaglandin synthetic activity of neural retina and retinal pigment epithelium in chick retina was studied using arachidonic acid and prostaglandin H2 (intermediate prostaglandin endoperoxide) as substrates. To obtain sufficient enzyme activity in retinal pigment epithelium, cultured chick retinal pigment epithelial cells were used. Little arachidonic acid was converted into prostaglandins, and details of prostaglandin synthetic activity were not clear. The assay from prostaglandin H2 showed that: 1) preparations consisting of both neural retina and retinal pigment epithelium dissected from 7-day-old chicks have activity of glutathione-requiring prostaglandin D2 synthetase; 2) preparations consisting of only neural retina dissected from 7-day-old chicks have no activity of prostaglandin synthetase; and 3) cultured chick retinal pigment epithelial cells have high activity of glutathione-requiring prostaglandin D2 synthetase.

Animals↗
PubMed1986

ERG c-wave and pigment granule distribution in isolated chick retina: effects of osmotic pressure variation in vitreal perfusing solution.

The relation between osmotic gradient variation and change in the ERG c-wave was investigated. The vitreous side of the isolated chick retina was perfused with various solutions having osmotic pressures (pi v) ranging between 310 and 600 mOsm, while the choroidal side was maintained at 480 mOsm (pi c). When the osmotic difference (delta pi), (ie, pi v-pi c), was larger than -10 mOsm, normal c-waves with slow rise-times (cs-wave) were obtained; however, when the delta pi was smaller than -30 mOsm, c-waves with fast rise-times (cF-wave) were recorded. The peak time of the cS-waves ranged from 4-6 seconds, while that of the cF-waves was approximately 2 seconds. In addition, changes in the pigment granule distribution were also investigated histologically and photometrically. At delta pi of +10 mOsm, the distribution of pigment granules was similar to that in the dark-adapted chick retina. However, when the delta pi was -30 mOsm, the distribution of pigment granules was similar to that in the light-adapted chick retina. Under the control condition at delta pi of +10 mOsm, the pigment granules were distributed mainly within the cell body of the pigment epithelium, ie, in a direction opposite to the passive flow determined by the artificial osmotic gradient. However, after treatment by ouabain, the granules were spread toward the neural retina in the same direction as the passive flow, suggesting passive movement of these granules. These results suggest that a steep osmotic gradient is present within the normal retina and that the gradient is maintained by an ATPase-dependent mechanism. Moreover, the above results suggest that the cS-wave is scotopic and the cF-wave is photopic.

Animals↗
PubMedDate not supplied

Nodular pigmented villonodular tenosynovitis.

Pigmented villonodular tenosynovitis is a proliferative disorder of the synovium that can involve the joints, tendon sheaths, and bursae. There are two histologically similar lesions of pigmented villonodular tenosynovitis--nodular pigmented villonodular tenosynovitis and diffuse pigmented villonodular tenosynovitis. The authors present a case involving nodular pigmented villonodular tenosynovitis, which is the more rare form of these two lesions.

Humans↗
PubMedDate not supplied

[Role of calcium-dependent and calcium-independent mechanisms in the adhesion of retinal and pigment epithelium cells in the chick embryo].

The mechanisms of adhesion of the retinal and pigment epithelium cells, as well of cell interaction within each of these tissues were studied during development. It was shown by means of separation of retina from pigment epithelium in different dissociation media that the adhesion of these tissues in 5-6 day old chick embryos is realized via a Ca2+-independent mechanism. The adhesion of these tissues decreases between days 7 and 16. Starting from day 16, both Ca2+-independent and Ca2+-dependent mechanisms are involved in the interaction of the retinal and pigment epithelium cells. By measuring the output of single cells into the suspension after the treatment of retina and pigment epithelium with different dissociating agents, it was shown that from the 5th day of incubation on the adhesion of pigment epithelium cells is mediated by Ca2+-dependent mechanism. In the retina three types of cells were found: interacting via Ca2+-dependent mechanism only, Ca2+-independent mechanism only, and both the mechanisms. In the course of differentiation, the numbers of the population of cells interacting only via Ca2+-dependent mechanism increase, while those of cells interacting via Ca2+-independent mechanism decrease. It is suggested that at each developmental stage those retinal cell possess Ca2+-dependent mechanism of adhesion which are closest to the definitive state.

Animals↗