Search results for "PIGMENTATION"
showing 10 items of 134 documents
Medication related to pigmentation of oral mucosa.
2021
The diagnosis of oral melanotic lesions is, more often than not, challenging in the clinical practice due to the fact that there are several reasons which may cause an increase in pigmentation on localized or generalized areas. Among these, medication stands out. In this work, we have carried out a review in the reference pharma database: Micromedex® followed by a review of the scientific published literature to analyse coincidences and possible discrepancies. Our findings show that there are several prescription drugs that can cause pigmented lesions in the oral mucosa. This must be known by clinicians in order to properly diagnose pigmented lesions. We have identified a set of 21 medicame…
Predator mimicry, not conspicuousness, explains the efficacy of butterfly eyespots
2015
Large conspicuous eyespots on butterfly wings have been shown to deter predators. This has been traditionally explained by mimicry of vertebrate eyes, but recently the classic eye-mimicry hypothesis has been challenged. It is proposed that the conspicuousness of the eyespot, not mimicry, is what causes aversion due to sensory biases, neophobia or sensory overloads. We conducted an experiment to directly test whether the eye-mimicry or the conspicuousness hypothesis better explain eyespot efficacy. We used great tits ( Parus major ) as model predator, and tested their reaction towards animated images on a computer display. Birds were tested against images of butterflies without eyespots, wi…
Effect of Pulp Pigmentation Intensity on Consumer Acceptance of New Blood Mandarins: A Cross-Cultural Study in Spain and Italy
2022
One of the current objectives of different citrus breeding programmes is obtaining new pigmented mandarins. This study investigates to what extent consumer preferences, expectations and purchase intention are affected by the appearance of new mandarins, specifically pulp pigmentation intensity. Four hundred consumers from both Italy and Spain (800 in all) participated in the study. In each country, half were informed about the healthy properties of the anthocyanins responsible for red pulp colouration, while the other half were not. Italians more readily accepted new mandarin varieties than Spaniards, which was linked to them being more familiar with blood oranges. In Italy, both slight- an…
Diplostomum spathaceum metacercarial infection and colour change in salmonid fish
2004
Colour changes in two salmonid fish, the salmon (Salmo salar) and sea trout (S. trutta), were examined in relation to infection with the trematode Diplostomum spathaceum. This parasite had no effect on the rate of colour change in these fish, although species specific differences in colour adjustment times were observed. Increasing asymmetry in parasite numbers between the right and left eye, which could lead to the retention of vision in one eye, nevertheless tended to reduce the colour change time in salmon with moderate infection (P=0.08). This first experimental attempt to examine colour changes in fish in relation to eye fluke infections provides grounds for future investigations. The …
Melanin type and concentration determination using inverse model
2011
Abnormality of melanin production causes skin pigmentation disorders. Currently, assessment of treatment efficacy (under Physician's Global Assessment framework) only refers to visual conditions of skin surface and not the condition of the underlying skin layers and pigments. Albeit researches on models and simulations of light interaction with human skin have been reported, none has been specifically developed for pigmentation analysis of melanin types - eumelanin and pheomelanin. Therefore, our research objectives are to develop image analysis of skin pigmentation for classification and quantification of eumelanin and pheomelanin pigment types in human skin. In this research, the model is…
A cross‐sectional, multi‐center study on treatment of facial acne scars with low‐energy double‐pass 1450‐nm diode laser
2020
Acne scars are the ultimate outcome of acne vulgaris, a prevalent skin disorder affecting the pilo-sebaceous unit. Laser resurfacing has been demonstrated to be an efficient therapy option for acne scars. Hence, we adopted this concept and conducted a study to evaluate the safety and efficacy of low-energy double-pass 1450-nm diode laser on acne scars. This study was conducted on 48 patients with acne scars, treated at 4-week interval with low-energy double-pass 1450-nm diode laser. Patients were evaluated clinically and with photographs, at day 0, first month and third month post the final treatment and during follow-up visit. Five treatment sessions were completed by all patients. Approxi…
Clinical Management of Cutaneous Adverse Events in Patients on Chemotherapy: A National Consensus Statement by the Spanish Academy of Dermatology and…
2019
Although the arrival of new chemotherapy drugs and combinations has brought progress in terms of cancer patient survival, they entail many adverse effects that can compromise treatment, and hence prognosis, of the disease. Cytostatic agents can cause dermatological toxicity, among other side effects. The most familiar adverse effect of chemotherapy is alopecia. Although not serious, this changes the outward appearance of cancer patients. Other adverse effects include hypersensitivity and photosensitivity reactions, hand-foot syndrome, epidermal necrolysis, recall reactions, scleroderma-like reactions, Raynaud's phenomenon, eccrine squamous syringometaplasia, neutrophilic eccrine hidradeniti…
Latanoprost-induced iris darkening: a morphometric study of human peripheral iridectomies.
2003
Abstract Purpose. This microscopic study was undertaken to compare the melanocytes of peripheral iridectomy specimens from two eyes that had latanoprost-induced iris darkening (LIID) with iridectomies taken from the fellow untreated eyes. Methods. The two patients in this study were the ones who underwent LIID in the latanoprost treated eye from a series of 17 patients requiring bilateral trabeculectomy. The first trabeculectomy procedure provided a control peripheral iridectomy for each patient, whereas the second eye was treated with once daily 50 μg ml−1 latanoprost drops for 6 months. The four peripheral iridectomy specimens from the two LIID patients were subjected to quantitative morp…
Hyperpigmentation of hard palate induced by chloroquine therapy
2017
The antimalarials are one of the most commonly prescribed drugs for conditions such as lupus erythematosus and rheumatoid arthritis, and the side effects, though infrequent, are well known. The antimalarial agent chloroquine diphosphate usually causes pigmentary changes in the oral mucosa characterized by a bluish-grey to black discolorations mainly in the hard palate. Considering only the hard palate hyperpigmentation caused by chloroquine, to the best of our knowledge, only 13 cases have been reported in the English language literature. We described an additional case of palate hyperpigmentation related to the chronic use of chloroquine diphosphate in a 60-year-old Mexican woman. Although…
Pharmacological Characterization of Loss of Function Mutations of the Human Melanocortin 1 Receptor That Are Associated with Red Hair
2004
Variation in skin color is the major host risk factor for melanoma and other forms of skin cancer. Individuals with red hair show an increased ratio of phaeomelanin to eumelanin in both hair and skin. This ratio is regulated by the melanocortin (MC) 1 receptor. There are several common point mutations in the human MC1 receptor that are overrepresented in North European red-heads, and in individuals with pale skin. In order to determine the functional significance of these mutations, we expressed the Asp84Glu, Val92Met, Arg163Gln, and Asp294His variants of the human MC1 receptors in eukaryotic cells and determined their ability to bind alpha-melanocyte stimulating hormone (MSH) peptides and …