PURPOSE To find CT and MR characteristics of normal leptomeningeal melanin, which can be macroscopically visible at autopsy in decedents with deeply pigmented skin. METHODS For the normal anatomic study, there were two black subjects who had brain MR and CT within 12 months before autopsy that showed leptomeningeal melanin. For the normal imaging study, brain MR was done on 74 patients (31 bl...

Near-infrared spectroscopy (NIRS) has shown promise in detecting ischemic changes in acute compartment syndrome. The objectives of this study were to 1) assess the correlation in NIRS values between upper and lower extremity control sites for bilateral lower extremity trauma and 2) investigate the effect of skin pigmentation on NIRS values. Forty-four volunteers (14 male, 30 female) were monito...

An unusual and attractive pigmentation pattern mutation termed "salmon" has been identified in the United States in several captive colonies of the common neotropical boine snake boa constrictor [Boa constrictor (Boidae)]. Boa constrictors expressing the Sa pigmentation pattern appear to be restricted to regions of Panama. Animals with the Sa phenotype exhibit a sharp decrease in melanophore pi...

A 42-year-old male, phototype III-IV, presented with an 8-month history of gradually enlarging pigmentation on the second finger of his left hand. He had no personal or familial history of skin cancer. No cryotherapy or other procedure was performed in this location. Naked-eye examination revealed an irregular hyperpigmented plaque extending from proximal to lateral nail fold, which appeared ir...

Melanic pigmentation results from melanin produced by the melanocytes present in the basal layer of the oral epithelium. One of the most common causes of oral pigmentation is smoker melanosis, a condition associated with the melanocyte stimulation caused by cigarette smoke. This paper aims to illustrate the use of a carbon dioxide laser in the removal of the gingival melanic pigmentation for ae...

Phenotypic plasticity describes the ability of a given genotype to produce distinct phenotypes in different environments. We use the temperature sensitivity of abdominal pigmentation in Drosophila melanogaster females as a model to analyse the effect of the environment on development. We reported previously that thermal plasticity of abdominal pigmentation in females involves the pigmentation g...

The mechanistic Target of Rapamycin Complex 1 (mTORC1) exerts multiple physiological functions, including nutrient sensing and the control metabolism, proliferation, senescence Wnt signaling. Yet, role mTORC1 activity in human hair follicle (HF) biology remains unknown. Since patients with a loss-of-function mutation key endogenous inhibitor activity, tuberous sclerosis complex (TSC), can show ...

Melanins play a fundamental role in the biology and ecology of several fungal species. Unfortunately, this group amorphous macromolecules also severely (and most times irreversibly) stains cultural heritage objects. Despite efforts made throughout years, knowledge chemical composition structure melanins is still insufficient, which hampers task safely cleaning these colourants from materials ta...

Skin patches with reduced pigmentation are the hallmark of acquired idiopathic illness vitiligo. Vitiligo was present in 0.5% to 2% world's population, an increase reaching 1.22% Egypt. The loss melanocytes, which produce melanin pigment skin, hair, mucous membranes, and retina, leads skin depigmentation this illness. Numerous hypotheses contend that genetics, environmental factors, autoimmune ...

Pigmentation during insect development is a primal adaptive requirement. In the silkworm, melanin is the primary component of larval pigments. The rate limiting substrate in melanin synthesis is tyrosine, which is converted from phenylalanine by the rate-limiting enzyme phenylalanine hydroxylase (PAH). While the role of tyrosine, derived from phenylalanine, in the synthesis of fiber proteins ha...