Search results for "PIGMENT"

Postzygotic KITLG mutation in a congenital non-progressive linear nevoid hyperpigmentation

2016

International audience

Interactions in the network of Usher syndrome type 1 proteins

2004

International audience; Defects in myosin VIIa, harmonin (a PDZ domain protein), cadherin 23, protocadherin 15 and sans (a putative scaffolding protein), underlie five forms of Usher syndrome type I (USH1). Mouse mutants for all these proteins exhibit disorganization of their hair bundle, which is the mechanotransduction receptive structure of the inner ear sensory cells, the cochlear and vestibular hair cells. We have previously demonstrated that harmonin interacts with cadherin 23 and myosin VIIa. Here we address the extent of interactions between the five known USH1 proteins. We establish the previously suggested sans-harmonin interaction and find that sans also binds to myosin VIIa. We …

Assessment of the toxicity of cholesterol oxides on retinal pigment epithelial cultured cells

2006

International audience; Purpose: Among the retinal lipid deposits found in AMD (age related macular degeneration), esterified and unesterified cholesterol have been identified. Cholesterol that accumulates in Bruch's membrane could be oxidized and lead to cholesterol oxides known as oxysterols. These compounds have cytotoxic activities on many vascular cell types, and we conducted this study to evaluate the cytotoxics effects of oxysterols on retinal pigment epithelial (RPE) cells. Methods: Human RPE cells (ARPE–19) were cultured and treated by 7–ketocholesterol (7–keto), 7–betahydroxycholesterol (7–beta) and 25–hydroxycholesterol (25–OH). ARPE–19 cells viability was determined with MTT ana…

Impact of the coronavirus pandemic on maxillofacial trauma:a retrospective study in southern Spain

2022

The coronavirus pandemic has impacted health systems worldwide, with Spain being one of the most affected countries. However, little is known about the extent to which the effects of staying home, social distancing, and quarantine measures have influenced the epidemiology of patients with maxillofacial trauma. The aim of this study was to analyze the impact of the coronavirus pandemic on the incidence, demographic patterns, and characteristics of maxillofacial fractures in the largest hospital in southern Spain. Data from patients who underwent surgery for maxillofacial fractures during the first year of the pandemic between 16 March 2020 and 14 March 2021 (pandemic group) were retrospectiv…

Chemometric Tools to Point Out Benchmarks and Chromophores in Pigments through Spectroscopic Data Analyses

2021

Spectral preprocessing data and chemometric tools are analytical methods widely applied in several scientific contexts i.e., in archaeometric applications. A systematic classification of natural powdered pigments of organic and inorganic nature through Principal Component Analysis with a multi-instruments spectroscopic study is presented here. The methodology allows the access to elementary and molecular unique benchmarks to guide and speed up the identification of an unknown pigment and its recipe. This study is conducted on a set of 48 powdered pigments and tested on a real-case sample from the wall painting in S. Maria Delle Palate di Tusa (Messina, Italy). Four spectroscopic techniques …

Epistatic interactions between pterin and carotenoid genes modulate intra-morph color variation in a lizard.

2021

Color polymorphisms have become a major topic in evolutionary biology and substantial efforts have been devoted to the understanding of the mechanisms responsible for originating such colorful systems. Within-morph continuous variation, on the other hand, has been neglected in most of the studies. Here, we combine spectrophotometric/visual modeling and genetic data to study the mechanisms promoting continuous variation within categorical color morphs of Podarcis muralis. Our results suggest that intra-morph variability in the pterin-based orange morph is greater compared to white and yellow morphs. We also show that continuous variation within the orange morph is partially discriminable by …

Flavonoīdu, melanīna un dzērveņu spiedpalieku ekstrakta antioksidatīvie efekti

2019

Antioksidanti ir vielas, kas var aizsargāt šūnas pret brīvo radikāļu iedarbību. Faktori, kas palielina brīvo radikāļu veidošanos organismā, var būt iekšēji, piemēram, iekaisums vai ārēji, piesārņojums, UV iedarbība un cigarešu dūmi. Lai nodrošinātu organismam normālu fizioloģisko funkciju, ir nepieciešams līdzsvars starp brīvajiem radikāļiem un antioksidantiem. Tāpēc intesīvi tiek meklēti efektīvi antioksidējoši dabiski savienojumi, kas nav toksiski. Labākie antioksidantu avoti ir augu produkti, īpaši augļi un dārzeņi. Darba mērķis: Izpētīt antocianīnu pārstāvja cianidīna, flavonola kvercetīna, melanīna un dzērveņu spiedpalieku ekstrakta antioksidantu īpašības. Iegūtie rezultāti liecina, ka…

Impiego della lmax del vino nel visibile come indicatore della presenza di antociani copigmentati

2007

Regulatory changes in pterin and carotenoid genes underlie balanced color polymorphisms in the wall lizard

2019

Significance Reptiles show an amazing color diversity based on variation in melanins, carotenoids, and pterins. This study reveals genes controlling differences between three color morphs (white, orange, and yellow) in the common wall lizard. Orange pigmentation, due to high levels of orange/red pterins in skin, is caused by genetic changes in the sepiapterin reductase gene. Yellow skin, showing high levels of yellow carotenoids, is controlled by the beta-carotene oxygenase 2 locus. Thus, the color polymorphism in the common wall lizard is associated with changes in two small regions of the genome containing genes with crucial roles in pterin and carotenoid metabolism. These genes are likel…

Antioxidant activities of prickly pear ( Opuntia ficus indica) fruits and its betalains: betanin and indicaxanthin.

2004

Phytochemicals and phytomedicines are now an expanding research fields. A great number of active agents occurring in plants and herbs have been discovered, which is fundamental to find a rationale for the health effects of these herbs, in many cases used for centuries as traditional remedies. The knowledge of the mechanisms and molecular basis of their action is the final objective to understand the mode of action of the discovered principles. Studies on the bioactivity of cactus pear are very recent and results obtained so far, while exciting, now generate new questions. In vivo studies on healthy humans showed a strong protection of the body antioxidant system, and a marked reduction of p…