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PubMed1983

[Nail pigmentation during therapy with cyclophosphamide and doxorubicin].

Two patients under cytotoxic therapy developed pigmentation of their fingernails. The first, under doxorubicin and cyclophosphamide for lymphoma, had horizontal streaks, while the second, under cyclophosphamide for periarteritis nodosa, exhibited diffuse pigmentation. Nail pigmentation, which occurs after an interval of some weeks or months, varies from diffuse to horizontal or longitudinal streaks. Reversal of nail pigmentation some months after withdrawal of the drug is usual. Skin or mucous membrane pigmentation may coexist. The mechanism of pigmentation remains obscure. These changes are observed more frequently in black than in white patients. In some instances, they have been recorded in several members of the same family.

Aged↗
PubMed1982

Mass cultivation of bovine ocular pigment epithelial cells in microcarrier suspension culture.

Recent developments in tissue culture technology permit the mass cultivation of anchorage-dependent cells in a compact and easily maintained system by utilizing the large surface area of suspended microspheres for cellular attachment and proliferation. The present study describes the successful cultivation of pure bovine iris pigment epithelium and mixed bovine retinal pigment epithelium-choroid by microcarrier suspension culture. Ocular pigment epithelial cells were collected from enucleated calf eyes and cultured in conventional monolayer fashion on flat plates. Subsequently, cells were harvested by trypsinization and were inoculated into microcarrier culture. Confluence was obtained in 8 to 12 days and final cell densities were 1 x 10(6) cells/ml for iris pigment epithelium and 8 x 10(5) cells/ml for combined retinal pigment epithelium--choroid; the microcarrier density was 5 gm/L. Samples from ongoing microcarrier cultures were processed for light and electron microscopic examination. Culture of bovine ocular pigment epithelial cells by microcarrier suspension technique provides a simplified method of cultivation of large numbers of cells, with additional advantages in ongoing culture maintenance and accessibility.

Animals↗
PubMed1982

Pigmented villonodular synovitis of joints.

In a series of 38 young adults with intra-articular pigmented villonodular synovitis, the joint predominantly affected was the knee. For early diagnosis of intra-articular pigmented villonodular synovitis, a high level of suspicion is necessary for patients with complaints of persistent pain or swelling in the knee, or erosive osteoarthritis of the hip and shoulder of unknown etiology in young individuals. Arthrography of the knee was not found to be a very helpful test in the diagnosis of pigmented villonodular synovitis. Localized intra-articular pigmented villonodular synovitis should be treated by local excision. Diffuse intra-articular pigmented villonodular synovitis of the knee should be treated by extensive synovectomy followed by manipulation under general anesthesia two to three weeks postsurgery. Intra-articular pigmented villonodular synovitis of the shoulder and hip should be treated by extensive synovectomy or by total joint arthroplasty in cases with marked bone destruction and cyst formation.

Adolescent↗
PubMed1978

Photoreceptors and visual pigments in a cichlid fish, Nannacara anomala.

Correlation of visual pigment content and photoreceptor cell structure is studied in the cichlid fish Nannacara anomala the retina of which is characterized by simple organization of the outer plexiform layer. The visual cell types consist of long and bulky rods and only two types of cones: equal double cones and short single cones. Both types of cones differ form other known teleost cones in that their outer segments are very slender yet twice as long as the inner segments. The double cones form a square mosaic with four doubles along the sides an a single cone in the center. Four rods usually surround the single cone and a few others lie in the corners of the square. The population densities of photoreceptor cells in the central part of the retina is 45,600 cones and 52,600 rods per mm2. The cone to rod ratio is 1:1.15; the double cone to single cone ratio is 4.07:1. The outer segments of photoreceptors contain four spectroscopic types of pigment: one type in rods with lambda max = 498 +/- 5 nm, one type in single cones with lambda max = 460 +/- 5nm, and one in each member of the double cones with lambda max of 555 +/- 5 and 600 +/- 10 nm. Single cones are found to contain only the blue-absorbing pigment. The double cones, whenever both members are successfully recorded from, appear to use two spectrally different pigments. Based on spectral bandwidth determination, the four pigments are probably of the prophyropsin class, although some admixture (10--20%) of rhodopsin-class pigments is also indicated, especially in double cones.

Animals↗
PubMedDate not supplied

[Antioxidative function of the melanoprotein granules of the rabbit pigment epithelium of the eye].

The intensity of peroxide oxidation of lipids in the pigmented epithelium of the eye, under hyperoxic conditions, is approximately 6 times lower in pigmented rabbits as compared to albino ones. In pigmented animals, the pigmented epithelium of the eye exerts evident protective effect during the action of oxygen on the retina. It is suggested that the observed inhibition of peroxide oxidation of lipids in the pigmented epithelium of pigmented animals is due to anti-oxidative effect of melanoprotein granules.

Animals↗
PubMedDate not supplied

[An analysis of keratin expression in the cells of the retinal pigment epithelium during transdifferentiation in newts].

Keratins of the cytoskeletal intermediate filaments have been identified immunohistochemically in pigment epithelium cells of the adult newt retina. We studied the expression of keratins in transdifferentiating and redifferentiating cells of the retinal pigment epithelium at different periods after removal of the retina. We have shown that the expression of keratins decreases. This appears as the decreased intensity of the immunospecific reaction soon after the operation. The latter observation has also been made immediately after artificial dissociation of the pigment epithelium cells of the retina isolated from nonoperated newt eyes. We found that the immunostaining of keratins was absent in the cells of normal and regenerating retina, as well as in retinal pigment epithelium cells before restoration of their structural and functional relationship with the retinal regenerate. The results obtained provide evidence for the inhibition of keratins expression during the transformation of retinal pigment epithelium into the retina. We proposed that there exists a mechanism responsible for gradual replacement of keratins by proteins of neurofilaments that have earlier been identified at the beginning of transdifferentiation of the retinal pigment epithelium.

Animals↗
PubMed1994

[Cultivation and ultrastructural investigation of human iris pigment epithelial cells].

UNLABELLED: The iris pigment epithelial cells of 10 human eyes were cultivated in vitro. RESULTS: The iris pigment epithelial cells obtained directly by scraping were easier to grow and to be passaged than those obtained by enzyme digestion. Under the inverted light microscope, primary cells appeared multigonal and arranged in monolayer, there were abundant pigment granules in the cytoplasm, and the nuclei each of which contained 1 or 2 nuclei were relatively transparent. Pigment granules diminished in succeeding generations. Under the transmission electron microscope, pigment granules were rich in the cytoplasm and there were plenty of microvilli at the cell membrane. There were maculae occludentes and desmosomes present in the intercellular space. The cultivated cells showed positive reaction of keratin antigen in an immunohistochemical assay. The characteristics mentioned above are consistent with the criteria of iris pigment epithelial cells.

Adolescent↗
PubMed1978

Correlations between quality and pigment parameters in young Beaujolais red wines.

The commercial qualities of 15 young Beaujolais red wines from the 1974 and 1975 vintages were scored by experienced tasters in the following summers. Measurements were made of a wine colour and the separate contributions to it by the coloured anthocyanins and the polymeric pigments, b total anthocyanins (coloured plus non-coloured) and c total pigments, i.e. total anthocyanins plus total polymers (coloured and non-coloured). All the tasting and analytical data were subjected to regression analysis. Statistically significant correlations were found in both years: a. Between overall quality and the contents of total pigments, total anthocyanins, coloured anthocyanins and the tasters' mean colour scores; b. Flavour and the contents of total pigments and total anthocyanins. Thus the colour of the acidified wine (total pigment) was the most simple indication of flavour and quality in these young wines of the same variety and age. In other respects there were marked differences between the vintages. In 1974 additional significant correlations were found a between overall quality and wine colour, pH and non-coloured anthocyanins, b between flavour and colour scores and coloured anthocyanins, and c between aroma and total pigments, total anthocyanins, coloured and non-coloured anthocyanins and pH. In 1975, flavour correlated with non-coloured anthocyanins and pH. The results demonstrate the desirable effects of anthocyanins on quality.

Anthocyanins↗
PubMed1995

Clinical correlates of gallstone composition: distinguishing pigment from cholesterol stones.

OBJECTIVES: The prevalence of cholelithiasis has been established in population-based surveys employing ultrasonography, and major risk factors have been identified. However, the clinical and epidemiological features that distinguish patients with pigment gallstones from those with cholesterol stones have received little attention. METHODS: We prospectively surveyed 551 patients undergoing cholecystectomy for gallstones at two teaching hospitals. Clinical and epidemiological data were collected during patient interviews and by chart review. Gallstones were collected at surgery; physical measurements were recorded, and stone composition was determined by visual inspection and infrared spectroscopy. RESULTS: Patients with pigment stones were older than patients with cholesterol stones (p < 0.00001). Almost all patients under age 40 yr old had cholesterol stones, but most patients over 70 had pigment stones. Cirrhosis was strongly associated with pigment gallstones (p < 0.00001), although alcohol consumption was unrelated. Univariate analyses suggested associations of stone composition with male sex, diabetes mellitus, educational attainment, and use of thiazides or oral contraceptives, but these were not significant in a logistic regression that adjusted for age, cirrhosis, and other variables. Patients with pigment cholelithiasis had stones that were generally smaller in diameter and fewer in number than those with cholesterol stones. CONCLUSIONS: Compared to patients with cholesterol gallstones, those with pigment stones are older and more likely to have a diagnosis of cirrhosis. In addition, their stones are smaller in size and fewer in number than those from patients with cholesterol cholelithiasis.

Adult↗
PubMed1994

Skin pigmentation as a predictor of minimal phototoxic dose after oral methoxsalen.

BACKGROUND AND DESIGN: Twenty-eight subjects were phototested to determine their erythemal responses to oral methoxsalen with UV-A and UV-B irradiation. Skin pigmentation was measured by skin reflectance at 550 and 660 nm before irradiation. The smallest UV radiation dose to produce erythema (minimal phototoxic dose and minimal erythema dose, respectively) was determined. The serum concentration of methoxsalen was measured at the time of UV-A irradiation. RESULTS: There was a positive correlation between skin pigmentation and both 72-hour minimal phototoxic dose and 24-hour minimal erythema dose. No correlation was demonstrated between methoxsalen serum concentration and minimal phototoxic dose. The combination of skin pigmentation and methoxsalen level did not give a better prediction of minimal phototoxic dose than skin pigmentation alone. CONCLUSIONS: Skin pigmentation measurements can be used to predict the minimal phototoxic and erythema doses. Skin pigmentation measurements are easy to perform and should be included in both phototherapy and photochemotherapy to improve the efficiency and reliability of the treatment.

Administration, Oral↗
PubMed1993

Synergistic suppression of retinal pigment epithelial cell proliferation in culture by radiation and hyperthermia.

PURPOSE: To study combination effects of radiation and hyperthermia on the in vitro cell proliferation of cultured human retinal pigment epithelial cells; to explore possible application of the combination treatment for proliferative vitreoretinopathy. METHOD: Cultured human retinal pigment epithelial cells were treated by radiation, hyperthermia, or a combination of the two. Cell proliferation was evaluated by counting the cell number and by the uptake of bromodeoxyuridine. RESULTS: X-ray irradiation of 100 cGy or 300 cGy was not effective in suppressing proliferation of the retinal pigment epithelial cells. Similarly, heat treatment at 42 degrees C or 43 degrees C for 30 min did not suppress proliferation of the retinal pigment epithelial cells. However, combination of hyperthermia at 42 degrees C for 30 min with 300 cGy irradiation suppressed cellular growth of the retinal pigment epithelial cells to 35.7% of the control as estimated by the cell counting and to 48.3% by bromodeoxyuridine uptake study. Combination treatment of 43 degrees C, 30 min hyperthermia and 300 cGy irradiation was more effective. CONCLUSIONS: A combination of low-dose radiation and mild hyperthermia is effective in the suppression of growth of cultured human retinal pigment epithelial cells, and the effects were found to be synergistic. It is expected that the synergistic effects will lower the radiation dose and also reduce the possible side effects of radiation in the treatment of proliferative vitreoretinopathy.

Cell Count↗
PubMed1995

Polymorphism in the number of genes encoding long-wavelength-sensitive cone pigments among males with normal color vision.

Examination by direct DNA sequence analysis of the X-linked visual pigment genes in 27 males with normal color vision reveals that almost half have two or more different genes encoding a long-wavelength-sensitive cone pigment. This is counter to the conventional theory proposed from results of Southern hybridization studies that there is a single long-wave pigment gene per X-chromosome. Further, the sequences and consideration of the structure of the X-linked pigment gene array suggest that the majority of the observers (as many as 2/3) have hybrid (or fusion) genes like those that have been proposed to underlie color anomaly. In some observers the long-wave hybrid genes contain a substantial amount of middle-wave sequence, e.g. five observers have hybrid long-wave genes that contain middle-wave sequences that include exon 4. Three of those five have the hybrid as their only long-wave gene, and thus have no other gene that could potentially encode a long-wave pigment. In these subjects, it is the hybrid gene that produces their normal long-wavelength-sensitive cone pigment. The high frequency of hybrid genes indicates that they are normal variant forms of the long-wave gene. Contrary to what is commonly believed, the introduction and the expression of hybrid genes is not sufficient to cause color vision defects.

Base Sequence↗
PubMed1996

What insights into vertebrate pigmentation has the axolotl model system provided?

Amphibians have been judiciously exploited by developmental biologists for many years for studying basic developmental mechanisms in vertebrates. In this review, the contributions that have been made by urodeles, in particular the axolotl (Ambystoma mexicanum), to the study of pigment cell biology are elaborated. Pigment cell differentiation is described, and the wild-type pigment phenotype is contrasted to pigment mutants such as albino, axanthic, melanoid, and white. Methods used for studying pigmentation, including recently developed molecular biological tools, are included to illustrate the significance of the axolotl as a model system for studying vertebrate pigmentation.

Ambystoma↗
PubMed1997

Individual variation in size of the human red and green visual pigment gene array.

PURPOSE: To determine the size variation of the X-chromosomal human red and green visual pigment gene array in the general population using pulsed field gel electrophoresis and Southern blotting. METHODS: Peripheral blood lymphocytes were prepared from 67 anonymous males. The cells were embedded in agarose and the genomic DNA digested with restriction enzyme Not I. The resulting DNA fragments were resolved on a contour-clamped homogeneous electric field gel, and the Not I fragment containing the red and green pigment genes was visualized by Southern blot hybridization with a human green pigment cDNA probe. RESULTS: In DNA from each male, a single hybridizing fragment was observed in Not I-digested DNA. The lengths of the fragments from different males were observed to vary in steps of approximately 39 kilobases (kb), consistent with earlier studies showing a visual pigment gene repeat unit of 39 kb and a head-to-tail tandem arrangement of the red and green visual pigment genes. In the population studied, the number of repeat units per X-chromosome had a mean of 2.9 and a standard deviation of 0.94. CONCLUSIONS: The sizes of visual pigment gene arrays observed in this study resemble those determined in earlier studies based on ratios of restriction fragments resolved by conventional gel electrophoresis and visualized by whole genome Southern blotting, but differ significantly from those determined using ratios of fragments obtained by the polymerase chain reaction.

Blotting, Southern↗
PubMed1977

[Isolation and characterization of pigment-protein complexes from green serobacteria Chlorobium limicola forma thiosulfatophilum].

A subchromatophore fraction containing the reaction center P-840 was isolated from the chromatophores of green serobacteria Chlorobium limicola forma thiosulfatophilum by ultracentrifugation and its protein composition was characterized. After treatment of the chromatophores by Triton X-100 and subsequent polyacrylamide gel electrophoresis two pigment-protein complex containing bacterioviridin. The proteins of the pigment-protein complex containing bacterioviridin. The proteins of the pigment-protein complexes were obtained. The first complex contained mainly bacteriochlorophyll alpha with bacterioviridin contaminations and the second one-only bacterioviridin. The low-temperature absorption spectrum of the bacteriochlorophyll alpha-containing pigment-protein complex is identical to the absorption spectrum of a water-soluble pigment-protein complex isolated and characterized by Olson and contains proteins with molecular weights of 34.800, 33.100, 27.500 and 23.200. A protein with molecular weight of 32.700 was found in the pigment-protein complexes were compared to the proteins of the photochemically active subchromatophore fraction and chromatophores.

Bacterial Chromatophores↗
PubMed1997

[Pigmented fibrosarcomatous dermatofibrosarcoma protuberans (Bednar tumor). 3 case reports, analogy with the "conventional" type and review of the literature].

BACKGROUND: The so-called Bednar tumor represents a pigmented variant of dermatofibrosarcoma protuberans (DFSP) and is characterized by a usually scant (1-5% of cells) population of dendritic melanocytes within an otherwise typical DFSP. This pigmented variant accounts for up to 5% of all DFSPs. Other variants of DFSP include cases showing features (in the primary or recurrence) of either giant cell fibroblastoma or fibrosarcoma. Less than 5% of DFSPs are associated with metastases and many of these show either a fibrosarcomatous component or, much more rarely, an "MFH"-like appearance. Only one previous case has been reported which showed combined features of the pigmented and fibrosarcomatous variants. MATERIALS: We present herein 3 cases of fibrosarcomatous Bednar tumor, all occurring in males, 2 aged 75 and 1 aged 23; two patients were white and one black. The tumors were located on the trunk or shoulder and two had been present for many years with recent rapid growth. One patient developed local recurrence and metastases to bone and lung and died within 1 year. The other two patients are disease free at 3 and 5 years follow-up respectively. All three cases showed typical histological features and in two tumors the pigment was evident macroscopically. CONCLUSIONS: A through literature review, including all cases of fibrosarcomatous DFSP and metastasizing fibrosarcomatous DFSP (whether or not pigmented), confirms that the fibrosarcomatous variant of DFSP (including its pigmented counterpart) is significantly more aggressive than usual DFSP, thus underlining the importance of its accurate recognition.

Adult↗
PubMed1953

Studies on the pathogenesis of kernicterus, with special reference to the nature of kernicteric pigment and its deposition under natural and experimental conditions.

Kernicteric pigment was extracted by means of chloroform from the brains of 3 infants. Solutions of it gave a positive diazo reaction, and, as determined electrophotometrically, gave maximum absorption of light having a wavelength of 425 mmicro, being identical in these properties with chloroform solutions of crystalline mesobilirubin. Experimental kernicterus was regularly induced by injecting crystalline mesobilirubin intracerebrally in newborn kittens, the pigment staining the cerebral tissues a bright canary-yellow and being deposited abundantly in the nerve cells, as microscopic examinations showed, although these latter were otherwise intact. Bilirubin, likewise injected intracerebrally in newborn kittens, had no such effects. The possibility is discussed that the blood-brain barrier is altered in some infants with hyperbilirubinemia in such a way that bilirubin crosses it and is then reduced within the brain to mesobilirubin thus giving rise to the cerebral pigmentation of kernicterus. The fact that the pigment itself does not seem to damage the neurons, as the present studies show, makes it necessary to seek some other cause for the neuronal damage that is sometimes seen, in association with the pigmentation, in the naturally occurring disease.

Bilirubin↗
PubMed2003

The normal and pathological pigmentation of oral mucous membrane: a review.

Pigmentation is both the normal and abnormal discoloration of oral mucous membrane. Pigmentation has multifactorial etiology. Most of the pigmentation is physiologic but sometimes it can be a precursor of severe diseases. Melanin pigment irregularities and color changes of the oral tissues could provide significant diagnostic evidence of both local and systemic disease. The differential diagnosis, clinical, etiology, and histopathological features of pigmentation are discussed and the current literature is reviewed.

Diagnosis, Differential↗