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PubMed2001

[Increased iris pigmentation after use of latanoprost in Japanese brown eyes].

PURPOSE: To evaluate the incidence of the increased iris pigmentation in Japanese with topical latanoprost. MATERIAL AND METHODS: One hundred and twelve patients who had homogeneous brown irises were studied. Age of the patients was 23 to 80(average 63.8 +/- 10.4) and follow-up periods were 6 to 12 (10.3 +/- 1.4) months. Slit lamp examination was carefully performed before use and at every month after use of latanoprost. Photographs were taken when necessary. The Kaplan-Meier life table method was used to evaluate the incidence of the increased iris pigmentation. RESULT: Iris pigment increase was observed in 47 patients. The incidence of the increased iris pigmentation was calculated as 10.1% at 3 months, 26.4% at 6 months, 50.1% at 9 months and 51.6% at 12 months after use. Pigmentation progressed as a granular concentric or sunrise pattern or a subtype of these. Some pigmentation occurred at one month after use, and progressed monthly. No patients noted their own iris color change, but were told by their relatives. Iris color changes of brown iris were considered to be less strong than in the hazel(green or blue/gray or yellow combined with brown) eye.

Adult↗
PubMed2001

Giant congenital pigmented naevus with unusual presentation and early malignant transformation in a Nigerian infant: case report and review of the literature.

A six month-old female infant with a giant congenital pigmented naevus is reported because of the rarity and unusual presentation and early malignant transformation. It was the first case to be documented in our centre. There was an extensive giant, darkly pigmented naevus of the "bathing trunk" distribution noted at birth, associated with multiple darkly pigmented smaller naevi scattered over the trunk and limbs. Bv the third month of life large pigmented lesion began to demonstrate small papillomatous projections studding the entire surface and at age six months nodular and warty excrescences appeared including a large pedunculated spherical mass attached to the anal verge. The labia majora became anatomically disfigured by these nodular, warty lesions of various sizes associated with the large pigmented hairy naevus. Histological examination of the excised large perianal and vulvar nodules showed the typical picture of an intradermal naevus consistent with giant congenital pigmented (melanocytic) naevus. The deeper portions of the lesion showed features of malignant transformation. The rapidity of evolution of the lesions including histologic features of early malignant transformation and the gross disfiguring of the genitalia and perineum are uncommon presentation of this melanocytic naevus. In view of the early malignant transformation immediate surgical treatment was indicated. Unfortunately the patient was lost to follow-up. The case report is complimented with a review of the literature.

Cell Transformation, Neoplastic↗
PubMed1998

Color vision defects with variation in the exon 5 of red and green pigment genes.

PURPOSE: To investigate correlation of variation in the exon 5 of red and green pigment genes with color vision defects. METHODS: Exon 5 of the red and green pigment genes in 11 protans, 19 deutans and 38 normal controls were analyzed by heteroduplux-SSCP analysis. RESULTS: In all 11 protans and 8 of the 19 deutans, defects of the red or green pigment gene could be identified. The C polymorphism (A/C at codon 283) in green pigment gene was present in 8 of 44 trichromats and 5 of 24 dichromats. Specific electrophoretic bands were found in 2 normal controls and a deutan. CONCLUSIONS: Variation in the exon 5 of the red and green pigment genes is the most common cause for color vision defects. Heteroduplex-SSCP analysis is a suitable way in screening specific variation in visual pigment genes.

Chromosomes, Human, X↗
PubMed2000

[Effect of tea polyphenols and tea pigments on inducing the activity of phase II detoxicating enzymes and on the chemoprevention of liver precancerous lesions].

In order to elucidate the chemoprevention mechanism of tea, the regulative effect of tea polyphenols and tea pigments on phase II enzyme, glutathions S-transferase (GST) activity and its isoenzymes in Wistar rat were studied. Rat liver precancerous lesions were initiated with diethylnitrosamine (DEN), promoted with partial hepatectomy and carbon tetrachloride. The rats were killed after 8 weeks of treatment. Liver cytosol GST activities were tested. The GST 1-1, 1-2, 3-3 and Pi isoenzymes were detected with Western Blot method. The results showed that the activities of GST increased greatly in the tea polyphenol and tea pigment groups, while the activities were decreased in positive control group. Both tea polyphenold and tea pigments increased the activities of classes GST alpha (GST1-1, 1-2) and GST mu(GST3-3). The increase of GST alpha was more in tea polyphenol group, and the increase of GST mu was more in tea pigment group. Both tea polyphenols and tea pigments inhibited the over expression of GST Pi in the rats treated with DEN/PH/CCl4. The study indicated that tea polyphenols and tea pigments modulated phase II enzymes effectively, thus inhibited the occurrence and development of the precancerous lesions of rat liver.

Animals↗
PubMed2003

An epidemiologic examination on the prevalence of the periodontal diseases and oral pigmentation in Yusho patients in 2002.

An epidemiologic examination was carried out to reveal the prevalence of the periodontal diseases and oral pigmentation in patients with Yusho. The results obtained were as follows. 1) 95 patients out of 110 patients, who were examined periodontal pocket depth using Ramfjord' methods, had at least one tooth with periodontal pocket deeper than 3 mm. Similarly, 276 teeth out of a total 495 examined teeth showed periodontal pockets with more than 3 mm depth. However, the ratio of the teeth with periodontal pockets deeper than 4 mm to total examined teeth in each age fell to less than 25%. 2) Oral pigmentation was observed in 75 patients out of 121 patients with Yusho. In this examination, gingival pigmentation was most predominant among oral pigmentation. It is of particular interest that severe pigmentation tended to be observed at a much higher frequency in younger patients with Yusho. Taken these findings into consideration, it was suggested that PCBs and related compounds might play an important role in the development of both periodontal diseases and oral pigmentation.

Adult↗
PubMed2004

[Study on extraction and stability of pigment from flowers of Leucosceptrum canum].

The yellow pigment from the flowers of Leucosceptrum canum is a traditional food pigment in some districts of Yunan Province. However, its structure and characteristics were unclear. In this study, the pigment showed two-absorbance peaks at 433 nm and 326 nm respectively. The pigment kept stable under the treatment of acid, light, heat, some metal ions, salt and sugar, and its stability was not affected by hydrogen peroxide without heat treatment, but affected by alkali and reducing agent such as sodium sulfite, and also hydrogen peroxide under heat treatment. The results of preliminary analysis showed that this pigment belongs to amines. It will be an ideal natural pigment for the food and pharmaceutical industry.

Chromatography↗
PubMed1992

Interocular differences in macular pigment density.

Interocular differences in the optical density of macular pigment were examined. Foveal and parafoveal sensitivities to lights of 460 and 530 nm were measured by heterochromatic flicker photometry for both eyes of ten subjects. These two wavelengths represent the maximum and minimum absorbance for macular pigment. Taking the difference in log sensitivity to the 460 nm light for the fovea and parafovea, after normalizing with respect to 530 nm, yields a measurement of the optical density of the macular pigment. Consistent interocular differences in macular pigment density were found for only two subjects, and these differences were less than 0.1. Other subjects frequently showed significant interocular differences on a given day but showed no consistent differences over the course of many days. In general, the amount of macular pigment measured for one eye was found to be essentially the same as that for the other eye. When measurements were averaged for the two eyes of each subject, significant differences in macular pigment density among subjects were found.

Adult↗
PubMed1991

Biological control of primate macular pigment. Biochemical and densitometric studies.

The amounts of zeaxanthin (Z) and lutein (L), the carotenoids constituting the primate macular pigment, were measured in the central retinas of monkeys (Saimiri sciureus and Macaca fascicularis). Two independent methods--reverse-phase high-performance liquid chromatography (HPLC) and microdensitometry--were used for analysis of the same set of retinas. Most of the measurements were made on retinas that had been fixed by glutaraldehyde-paraformaldehyde perfusion of the animal. Control experiments showed that this fixation did not interfere with the quantitative extraction and analysis of the carotenoids. The amount of macular pigment calculated from microdensitometry of the foveal region was proportional to the amount of pigment assayed by HPLC of the same retinal area, demonstrating that either method can be used reliably to rank the carotenoid content of aldehyde-fixed foveas. The optical density of pigment in the axial direction through the retina was higher than would be predicted if the pigment were randomly oriented. This is consistent with the idea that the nonrandom orientation of the dichroic macular pigment molecules found in previous studies contributes to increased optical filtering of the retinal image. Comparisons of the amounts of Z and L between the left and right eyes of the same monkey, within 1 mm of the foveal center, always showed excellent agreement (averaging a 5% difference for Z and 11% difference for L), whereas differences among individual monkeys were very large (up to fourfold for Z). These results indicate that the uptake and assimilation of the macular carotenoids are biologically regulated by selective mechanisms in primate retinas.

Animals↗
PubMed1989

Retinal attachment to the pigment epithelium. Linkage through an extracellular sheath surrounding cone photoreceptors.

The interphotoreceptor matrix, which occupies the so-called subretinal space in normal human eyes, was examined with electron microscopy after treatment with Cuprolinic Blue, a dye that selectively stains sulfated polyanions. A cylindrically shaped, extracellular ensheathing domain, composed of Cuprolinic Blue-positive particles, was observed surrounding each cone photoreceptor examined. Equivalent structures were not present around rods. Surrounding peripheral cones, the unit particles which comprised the sheath, were punctate in shape whereas in foveal and foveolar cones the particles were more elongate. A matrix domain completely enveloped each cone photoreceptor, beginning at the outer limiting membrane, extending beyond the tip of the cone outer segment, and ending at the apical surface of the pigment epithelium. Proximal to the pigment epithelium, specialized extensions of apical microvilli were present in the lumen of the matrix sheath and shorter microvilli appeared to be embedded in the sheath wall. When retinas were experimentally detached from the pigment epithelium and washed extensively before fixation and staining, the cone matrix domains remained associated with the cones, and broken fragments of pigment epithelial cell processes were present embedded in the distal tip of the cone matrix sheath wall. These observations indicate that the cone matrix sheath is insoluble and is closely associated with both the cone photoreceptor and the apical surface of the pigment epithelium. The implication of these findings is that the cone matrix sheath is a bridge through which the retina and pigment epithelium are physically attached.

Adolescent↗
PubMed1985

Disease expression in cultured pigment epithelium. Feline mucopolysaccharidosis VI.

Primary cultures of retinal pigment epithelial (RPE) cells from cats with mucopolysaccharidosis VI (MPS VI) have been initiated from mixed populations of cells (ie, derived from the entire eyecup and represented by both pigmented and nonpigmented RPE cells). The cells were enzymatically dissociated from the eyecup and seeded at 6 X 10(4) cells/cm2. Cells from normal and affected cats formed confluent monolayers of polygonal cells between 5-10 days in culture and maintained most of their in vivo morphologic characteristics. The only abnormality observed in the MPS VI-affected cultures was the accumulation of vacuolated intracytoplasmic inclusions; when numerous, these vacuoles caused cellular hypertrophy. Hypertrophy was present only in cells devoid of pigment. Pigmented cells adjacent to or near the hypertrophied cells exhibited little or no accumulation of vacuoles. The inclusions were indistinguishable from those observed in vivo in terms of size, distribution, and appearance. The MPS VI-affected RPE exhibited deficient arylsulfatase B (ASB) activity (RPE-ASB activity: normal = 506 nmol/hr/mg protein; affected = 22 nmol/hr/mg protein), whereas the activities of two other lysosomal enzymes, arylsulfatase A and alpha-L-iduronidase, were normal. A method was developed to initiate primary cultures of RPE cells from defined regions of normal and MPS VI-affected eyes. Studies indicated that cultures initiated from superior-equatorial regions (RPE nonpigmented) contained more vacuolated cytoplasmic inclusion than those initiated from inferior-equatorial regions (RPE pigmented). These findings indicated that the spatial distribution characteristic of the disease in vivo was maintained in culture and that disease expression was inversely correlated with pigmentation.

Animals↗
PubMed1989

Pigmented guinea pig skin irradiated with Q-switched ruby laser pulses. Morphologic and histologic findings.

Q-switched ruby laser pulses cause selective damage to cutaneous pigmented cells. Repair of this selective damage has not been well described. Therefore, using epilated pigmented and albino guinea pig skin, we studied the acute injury and tissue repair caused by 40-ns, Q-switched ruby laser pulses. Gross observation and light and electron microscopy were performed. No specific changes were evident in the albino guinea pigs. In pigmented animals, with radiant exposures of 0.4 J/cm2 or greater, white spots confined to the 2.5-mm exposure sites developed immediately and faded over 20 minutes. Delayed depigmentation occurred at seven to ten days, followed by full repigmentation by four to eight weeks. Regrowing hairs in sites irradiated at and above 0.4 J/cm2 remained white for at least four months. Histologically, vacuolation of pigment-laden cells was seen immediately in the epidermis and the follicular epithelium at exposures of 0.3 J/cm2 and greater. Melanosomal disruption was seen immediately by electron microscopy at and above 0.3 J/cm2. Over the next seven days, epidermal necrosis was followed by regeneration of a depigmented epidermis. By four months, melanosomes and melanin pigmentation had returned; however, hair follicles remained depigmented and devoid of melanocytes. This study demonstrates that selective melanosomal disruption caused by Q-switched ruby laser pulses leads to transient cutaneous depigmentation and persistent follicular depigmentation. Potential exists for selective treatment of pigmented epidermal and dermal lesions with this modality.

Animals↗
PubMed1987

Organic pigments in plastics can cause allergic contact dermatitis.

A short review on organic pigments in plastics as a cause of allergic contact dermatitis is presented. Previously, organic pigments have been reported as provoking allergic pigmented contact dermatitis when used in cosmetics. Here we present the case of a patient who developed allergic contact dermatitis from an organic pigment (Irgalite Orange F2G) in a plastic glove. This shows that organic pigments in plastics can also cause allergic contact dermatitis. The potential sensitizing capacity of organic pigments should be noted.

Coloring Agents↗
PubMed1987

Appearance of polychromic endothelial pigment.

Multicolored corneal endothelial pigment was noted in patients on routine specular microscopy, confirming the presence of chromatic pigment deposits at the corneal endothelium. These deposits were polychromic, exhibiting blue, green, red, pink, orange, gold, and yellow colors. These pigment deposits were of different sizes and shapes and often seemed to surround darkened cells or clusters of cells. The variations in color may be the result of differing concentrations of melanin in iris or other pigmented cells that adhere to the posterior surface of the corneal endothelium. To our knowledge, this is the first report of the observation of polychromic endothelial pigment. We encourage the use of color film for specular microscopy to help detect and identify this pigment further.

Aged↗
PubMed1986

[Cutaneous pigmentation induced by minocycline: 2 cases].

Two new cases of cutaneous pigmentation induced by minocycline are reported, in addition to the 38 cases collected in the literature. Our first case was a 50-year old man with a history of multiple orthopaedic operations for injuries sustained in road accidents. Arthritis of the elbow, probably of bacterial origin, was treated with cephalexin and gentamicin, followed by minocycline 300 mg/day. After a total dose of 60 g of minocycline had been reached, a bluish-grey pigmentation was observed on the internal aspect of the left tibia and on the scars left by the orthopaedic operations. Subsequently, lenticular lesions of the hands developed, together with a blue area on the palate. Our second case was an 18-year old girl who presented initially with nodulo-cystic acne. Minocycline 200 mg/day was prescribed, then withdrawn on account of dizziness; no pigmentation was observed. The acne was cured after 7 months of treatment with 13-cis-retinoic acid in doses of 30 mg/day (for a patient's weight of 50 kg). A second course of minocycline 100 mg/day was prescribed; after a total dose of 3 g all the acne scars had become pigmented. A pathological study performed in the first case confirmed the data found in the literature: light microscopy displayed hyperpigmentation of the basal layer of the epidermis with Masson's silver stain, and an intrahistiocytic pigment coloured by Turnbull's stain; electron microscopy showed an increase in melanosomes within the basal keratinocytes, and a pathological accumulation of pigment in the dermis in the form of electron-dense granules usually surrounded by a membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1985

[Cronkhite-Canada disease. Discussion apropos of a case and study of the pigmentation].

In 1955, Cronkhite and Canada described two patients presenting abnormal skin pigmentation, alopecia, onychodystrophy and gastrointestinal polyposis. In the first French case reported here, the skin pigmentation has been the object of a special electron microscope study. M. E..., 48-year old, developed, in 1968, pigmented maculae with a metallic gloss around his pelvic girdle. The melanoderma rapidly expanded, associated with fall of hair, body hairs and eyebrows. Onyxis and perionyxis of the right thumb, milium-like epidermal cysts, tumoral lesions of the keratoacanthoma type on the nose and scrotum and, chiefly, generalized cockade-like bullous erythema associated with buccal erosions soon completed the clinical picture. The bullae were subepidermal, and direct and indirect immunofluorescence tests revealed the presence of antibodies directed against the basal membrane area. A few years later, a gastrointestinal syndrome developed progressively, consisting of liquid diarrhoea (8-10 stools per day) with deterioration of the patient's general condition and loss of weight leading to cachexia and, ultimately, death. During periods when the gastrointestinal symptoms regressed the general condition improved, hair and hairs started growing again and pigmentation was less pronounced. Examinations of the digestive tract discarded a malabsorption syndrome. Endoscopy revealed the presence of false polyps with paved appearance of the colonic and rectal mucosae. The mucosa was congested, inflamed and strewn with ulcerations. Histology showed signs of acute proctitis. The abnormal skin pigmentation was the object of histological and ultrastructural analysis. Under the light microscope the epidermis was thicker than normally with increased melanin content. There was marked pigment leakage with numerous melanophages. At electron microscopy the melanocytes, more numerous, showed increased melanogenic activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Alopecia↗
PubMed1979

Corneal transplantation for endothelial pigmentation.

Endothelial pigmentation does not usually interfere with vision. This case report documents a dense and extensive deposition of uveal pigment in corneal endothelial cells of a patient who had undergone 2 previous grafts subsequent to an alkali burn injury. The previous graft in which the pigmentation occurred remained compensated, but vision was impaired secondary to dense endothelial pigmentation. A combination of the initial chemical injury, recurrent iritis, chronic glaucoma, and multiple intraocular procedures may have resulted in the stimulus for the uveal tract to disperse a large amount of pigment onto the cornea and its subsequent phagocytosis by the endothelium. Endothelial pigmentation may become a more commonly seen complication in attempts to treat the severely damaged anterior segment.

Adult↗
PubMed1979

[Mitotic activity of the pigment epithelium during embryonic and postembryonic development].

The purpose of the present study was to examine the mitotic activity of the normal pigment epithelium of the retina (RPE), the ciliary body and the iris of different animals during gestation and after birth by blocking the metaphase with colchicine and by marking the pigment epithelial nuclei with tritium-labeled thymidine. The colchicine examinations were made on 54 albino rabbits and 56 albino rats, the 3H-thymidine studies with 78 albino mice. In the rabbit the peak of mitotic activity (respectively the end) is found in the RPE at the beginning of the 2nd third of gestation (respectively at the 9th postnatal day), but in the pigment epithelium of the ciliary body and in the iris during the last third of gestation (respectively in the 2nd month of life and the 3rd postnatal week). In the rat the highest mitotic activity is reached in the RPE at the beginning of the 2nd half of gestation (respectively at the 13th postnatal day), in the ciliary body at the 3rd day of life (respectively the 24th postnatal day) and in the iris at the end of the gestational period (respectively the 17th postnatal day). In the mouse the highest rates of mitotic activity are found in the RPE from the 16th gestational day to the 8th day of life (respectively the 20th day of life), in the ciliary body from the 1st to the 4th day of life (respectively from the 12th to the 20th postnatal day) and in the iris on the 9th day of life (respectively the 12th to the 20th postnatal day). The present observations have also demonstrated that with maturation of all areas of the pigment epithelium, the mitotic activity stops. The cells of the pigment epithelium do not have an epithelial cell turnover but they are reversible postmitotic cells. Despite the enormous proliferative properties the pigment epithelium shows no regeneration by mitosis after severe damage.

Animals↗
PubMed1977

[Pharmacological studies of Shikon and Tooki. (2) Pharmacological effects of the pigment components, Shikonin and acetylshikonin].

Pharmacological effects of Shikonin and Acetylshikonin, pigment components of Shikon were studied in mice, rats, guinea pigs and rabbits. The only difference between the chemical structures of the two pigments is that Acetylshikonin has the acetyl radical, while Shikonin does not. Though the activity was slightly different between the two compounds, the pharmacological effect of Shikonin was similar to that of Acetylshikonin. As the two pigments were extracted by ether from Shikon, systemic administration of these pigments showed the same effect as that of ether extract of Shikon as outlined in the first report(1). These compounds had no effect on blood coagulation, but inhibited the anticoagulant effect of heparin in rats. Topical application of both pigments (50 mg of 0.1% ointment) inhibited an increased vascular permeability and acute edema induced by histamine, anti-rat rabbit serum and heat. The activity was similar to that of 0.1% phenylbutazone ointment. On the other hand, these pigments increased proliferation of granuloma tissue in the cotton pellet method and promoted would healing in rats. The results suggest that Shiunko, a main prescription of Shikon, is an effective ointment for cutaneous injuries.

Analgesics↗