Search results for " pigment"

Novel inulin-based mucoadhesive micelles loaded with corticosteroids as potential transcorneal permeation enhancers

2017

In this work a new copolymer of inulin (INU) derivatized with ethylendiamine (EDA) and retinoic acid (RA), named INU-EDA-RA, was synthetized, characterized and employed to produce micelles as carriers for topical administration of corticosteroids for the potential treatment of diseases of posterior eye segment. Spectroscopic analysis confirmed a molar derivatization degree of 11.30 and 4.30% in EDA and RA, respectively. INU-EDA-RA micelles are capable of strong mucoadhesive interactions which result time-independent and stable over time but concentration depending. Moreover micelles are able to encapsulate efficiently from 3 to 13% (w/w) of lipophilic drugs, as dexamethasone, triamcinolone …

A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

2018

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The Europea…

Biochemical indicators for novel forest decline in spruce

1998

Abstract The impact of air pollution on 24 stands of spruce trees in several regions in Germany was investigated. We looked for evidence of biochemical and physiological change at the level of the photosynthetic thylakoid membranes as well as for changes in the antioxidative system in two year old needles. We observed that, as the chlorophyll content decreases in the needles, the amoung of D1 protein declines far more rapidly in relation to the redox components P700 and cytochrome f. Consequently, the PSII/PSI stoichiometry keeps dropping to pregressively lower, meaning unfavorable, values at the chlorophyll content diminishes. This is particularly the case in the higher elevation character…

The colours of Segesta. Searching for the traces of the lost pigments

2023

Many monuments and objects of the ancient civilizations were painted, but unfortunately the pigments are not still present and sometimes only small traces are evident. The analysis of the traces requires a multianalytical approach through the use of non-invasive techniques and only if necessary of a microsampling. Here, the study of the traces of colours found in some architectural elements and findings belonging to the Archeological Park of Segesta (Trapani, Italy) is reported. The traces are identified and characterised via several techniques such as Optical Microscopy, UV-Fluorescence Imaging, Fiber Optical Reflectance Spectroscopy (FORS), X-ray Fluorescence (XRF) and FT-IR Spectroscopy.…

Application of ultrasound as clean technology for extraction of specialized metabolites from stinging nettle (Urtica dioica L.)

2022

Nettle is a highly valued medicinal plant that is still largely neglected, both in terms of nutrition and use for pharmacological purposes. Tinctures, i.e., alcoholic extracts, are becoming increasingly popular nettle products, mainly because they allow better availability of phytochemicals and their stability over a longer period of time. The production of alcoholic extracts is a chemically demanding process that is still usually carried out using conventional techniques, which have numerous drawbacks. The use of green technologies such as ultrasound-assisted extraction (UAE), which is characterized by high efficiency of phytochemical extraction, shorter treatment time, and a much lower en…

New record in the Mediterranean Sea of unusual skin colouration in the black-bellied anglerfishLophius budegassaSpinola, 1807

2010

Scienza e Arti Perdute: i Segreti degli Antichi Maestri Liutai

2011

Lo scopo di questo lavoro è illustrare agli insegnanti la connessione tra due settori di attività apparentemente lontani: la scelta dei materiali utilizzati nella liuteria artigianale e la chimica. Il ruolo, la composizione e la classificazione delle principali vernici per liuteria sono qui descritte assieme ad una breve sintesi dello stato dell’arte. Nel lavoro, vengono presentati i principali concetti di una tecnica analitica non distruttiva abbastanza semplice (la spettroscopia di fluorescenza da raggi X) ma, probabilmente, non abbastanza nota ai non addetti ai lavori. Un caso di studio a essa correlato è inoltre presentato per evidenziare uno dei possibili contributi del chimico nello s…

Life History Trade-Offs and Relaxed Selection Can Decrease Bacterial Virulence in Environmental Reservoirs

2012

Pathogen virulence is usually thought to evolve in reciprocal selection with the host. While this might be true for obligate pathogens, the life histories of opportunistic pathogens typically alternate between within-host and outside-host environments during the infection-transmission cycle. As a result, opportunistic pathogens are likely to experience conflicting selection pressures across different environments, and this could affect their virulence through life-history trait correlations. We studied these correlations experimentally by exposing an opportunistic bacterial pathogen Serratia marcescens to its natural protist predator Tetrahymena thermophila for 13 weeks, after which we meas…

Correction for Frantz et al., Ancient pigs reveal a near-complete genomic turnover following their introduction to Europe

2020

Significance Archaeological evidence indicates that domestic pigs arrived in Europe, alongside farmers from the Near East ∼8,500 y ago, yet mitochondrial genomes of modern European pigs are derived from European wild boars. To address this conundrum, we obtained mitochondrial and nuclear data from modern and ancient Near Eastern and European pigs. Our analyses indicate that, aside from a coat color gene, most Near Eastern ancestry in the genomes of European domestic pigs disappeared over 3,000 y as a result of interbreeding with local wild boars. This implies that pigs were not domesticated independently in Europe, yet the first 2,500 y of human-mediated selection applied by Near Eastern Ne…

Differential Distribution of Harmonin Isoforms and Their Possible Role in Usher-1 Protein Complexes in Mammalian Photoreceptor Cells

2003

PURPOSE. Human Usher syndrome is the most common form of combined deafness and blindness. Usher type I (USH1), the most severe form, is characterized by profound congenital deafness, constant vestibular dysfunction, and prepubertal onset retinitis pigmentosa. Previous studies have shown that the USH1-proteins myosin VIIa, harmonin, and cadherin 23 interact and form a functional network during hair cell differentiation in the inner ear. The purpose of the present study was to analyze the molecular and cellular functions of these USH1 proteins in the mammalian retina. METHODS. Antibodies to USH1 proteins were generated and used in Western blot analysis of subcellular photoreceptor fractions a…