Search results for " pigment"

Response to ozone in two lettuce varieties on chlorophyll a fluorescence, photosynthetic pigments and lipid peroxidation.

2004

The effect of different O3 concentrations on two lettuce (Lactuca sativa L.) varieties (Valladolid and Morella) was investigated through chlorophyll (Chl) a fluorescence parameters, photosynthetic pigments (Chl a, b and total carotenoid), lipid peroxidation and crop yield. Ozone fumigation caused: a decrease in maximum quantum yield of photosystem II (PSII) photochemistry (Fv/Fm) in mature leaves, a reduction in the non-cyclic electron flow (phiPSII) and a lower capacity to reoxidize the QA pool (qP). These reductions were significant in the Valladolid var. but not in the Morella var. A significant decrease in Chl a, b and in the total carotenoids was observed in the Valladolid var. but not…

Through-bond versus through-space T1 energy transfers in organometallic compound-metalloporphyrin pigments

2009

The preparation and characterization of two d9−d9 M2-bonded Pt2(dppm)2(C≡CC6H4-M(P))2 complexes (where M = Zn or Pd, and P = diethylhexamethylporphyrin) were achieved. The central [Pt2(dppm)2(C≡CC6H4)2] organometallic unit appears to be an independent chromophore and is suspected to be luminescent at 77 K (in 2MeTHF) in the porphyrin-containing complexes, as this is the case for the unfunctionalized Pt2(dppm)2(C≡CPh)2 parent compound. However, when this spacer is connected (by a single C−C bond) to either M(P) (M = Zn, Pd), even in the absence of conjugation (as the computed dihedral angle between the C6H4 and porphyrin planes is ∼84.5°), total quenching of the luminescence of the [Pt2(dppm…

PCARE and WASF3 regulate ciliary F-actin assembly that is required for the initiation of photoreceptor outer segment disk formation

2020

Significance The photoreceptor outer segments are primary cilia, modified for phototransduction by incorporation of stacked opsin-loaded membrane disks that are continuously regenerated. This process is disrupted in several types of inherited retinal dystrophy, but the driving force remained unclear. We show that C2orf71/PCARE (photoreceptor cilium actin regulator), associated with inherited retinal dystrophy subtype RP54, efficiently recruits the Arp2/3 complex activator WASF3 to the cilium. This activates an actin dynamics-driven expansion of the ciliary tip, resembling membrane evagination in lamellipodia formation. Colocalization of this actin dynamics module to the base of the outer se…

Activity and kinetics of DNA dependent DNA and RNA polymerases n xeroderma pigmentosum and in normal human skin.

1971

1. DNA dependent DNA polymerase (E.C.2.7.7.7) was prepared from human normal and from Xeroderma pigmentosum skin. 2. DNA polymerase from normal skin has the same Michaelis constant with native and denatured DNA as templateKm= 120 ± 11 µg DNA/ml, with differing maximum reaction velocities. 3. The enzyme from Xeroderma pigmentosum has the same Michaelis constant for denatured DNA as the enzyme from normal skin, but with native DNA as template, theKmvalue is lower (97.2 ± 9.8). The maximum reaction velocities of the Xeroderma pigmentosum enzyme with native resp. denatured DNA as template are the same. 4. DNA dependent RNA polymerases (E.C.2.7.7.6) from normal and Xeroderma pigmentosum skin wer…

Gallium(III) and Indium(III) Complexes with meso-Monophosphorylated Porphyrins: Synthesis and Structure. A First Example of Dimers Formed by the Self…

2017

International audience; The synthesis and structural characterization, both in solution by means of H-1 and P-31 NMR and UV-vis spectroscopies and in the solid state by X-ray diffraction on single crystal, of a series of gallium(III) and indium(III) meso-mono(diethoxyphosphoryl)porphyrins bearing different peripheral substituents as well as the corresponding monoesters and phosphonic acids are reported. This work describes the first example of the X-ray structure of a self-assembled dimer formed via strong binding between the oxygen atom of the phosphonate substituent and the gallium(III) cations of adjacent porphyrin molecules [Ga-O = 1.9708(13) angstrom].

Beneficial effects of saffron (

2020

Saffron (Crocus sativus L.) has been traditionally used in food preparation and as a medicinal plant. It currently has numerous therapeutic properties attributed to it, such as protection against ischemia, as well as anticonvulsant, antidepressant, anxiolytic, hypolipidemic, anti-atherogenic, anti-hypertensive, antidiabetic, and anti-cancer properties. In addition, saffron has remarkable beneficial properties, such as anti-apoptotic, anti-inflammatory and antioxidant activities, due to its main metabolites, among which crocin and crocetin stand out. Furthermore, increasing evidence underwrites the possible neuroprotective role of the main bioactive saffron constituents in neurodegenerative …

Evaluación de estrategias terapéuticas basadas en sustancias antiinflamatorias y antioxidantes en retinosis pigmentaria

2020

La retinosis pigmentaria comprende un grupo de distrofias hereditarias de retina, caracterizadas por la pérdida progresiva e irreversible de la visión, debida a la muerte de las células fotorreceptoras. Se trata de una enfermedad rara, que constituye la principal causa genética de ceguera, con una prevalencia de un afectado por cada 4000 habitantes. Mientras que la degeneración retiniana empieza con la muerte de los bastones debida a mutaciones genéticas, la muerte de los conos parece ser consecuencia de un progresivo daño oxidativo, inflamación y desequilibrio metabólico, influenciado por la liberación de sustancias tóxicas por parte de los bastones y otras células del entorno. La muerte d…

Prodotti innovativi premiscelati per il rivestimento superficiale di edifici: attività fotocatalitica ed influenza dei pigmenti minerali

2009

Preliminary Study of the Mural Paintings of Sotterra Church in Paola (Cosenza, Italy)

2022

A multi-analytical approach was employed to study wall paintings located in the Sotterra church at Paola, in the province of Cosenza, Italy. The site is an underground church (hence the name of Sotterra, which means “under the earth”) rediscovered in the second half of the 19th century, during the building works of the Madonna del Carmine church on the same area. This underground church preserves valuable mural paintings having different styles. The construction’s dating and overlapped modifications made until the site was abandoned is also debated. A wall painting, depicting “The Virgin” as part of the “Annunciation and the Archangel Gabriel” prese…

Electrofunctional features of the tilted disc syndrome.

1986

The ERG, EOG and VEPs of 15 patients with tilted disc syndrome were studied. The ERG showed abnormal amplitudes in about 1/4 of the eyes and the EOG values were pathological in 3 patients. It is probable that the abnormality of the inferior-nasal portion of the retina and retinal pigment epithelium seen in the tilted disc syndrome causes the changes in the ERG and EOG. Pattern VEPs latency was delayed in most patients. This finding is probably due to the poor focusing of the light in the retina.