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1.
RSC Adv ; 10(24): 14099-14106, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35498498

RESUMEN

Electroplex emission is rarely seen in ruthenium polypyridyl complexes, and there have been no reports from light-emitting electrochemical cells (LECs) to date. Here, for the first time, near-infrared (NIR) emission via the electroplex mechanism in a LEC based on a new blend of ruthenium polypyridyl complexes is described. The key factor in the design of the new complexes is the 0.4 V decrease in the oxidation half-potential of Ru(ii)/Ru(iii) in [Ru(DPCO)(bpy)2]ClO4 (DPCO = diphenylcarbazone, bpy = 2,2 bipyridine), which is about one-third of the value for benchmark [Ru(bpy)3](ClO4)2, as well as the long lifetime of excited states of 350-450 ns. The LEC based on the new blend with a narrow band gap (≈1.0 eV) of a Ru(DPCO) complex and Ru(bpy)3 2+ can produce an electroluminescence spectrum centred at about 700 nm, which extends to the NIR region with a high external quantum efficiency (EQE) of 0.93% at a very low turn-on voltage of 2.6 V. In particular, the very simple LEC structure was constructed from indium tin oxide (anode)/Ru(DPCO):Ru(bpy)3 2+/Ga:In (cathode), avoiding any polymer or transporting materials, as well as replacing Al or Au by a molten alloy cathode. This system has promising applications in the production of LECs via microcontact or inkjet printing.

2.
ACS Omega ; 3(8): 9981-9988, 2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-31459126

RESUMEN

Deep red light-emitting electrochemical cells were prepared based on a blend of [Ru(bpy)3]2+, a cationic complex, and a neutral Zn(II)-complex based on diphenylcarbazone ligands, named Zn(DPCO). The crystal structure of the Zn(DPCO)2 (bpy)] molecule revealed that the DPCO ligand has been deprotonated to form DPCO- and coordinated to the Zn center metal through the C=O and N=N moieties of DPCO. From the cyclic voltammetry results and controlled potential coulometry data of the diphenylcarbazide (DPC) ligand, it is possible to establish that DPC is oxidized in an irreversible process at +0.77 V, giving DPCO and later oxidized at a higher potential (+1.32 V) to produce diphenylcarbadiazone (DPCDO). A detailed assignment of UV-vis spectra futures to determine the origin of ground- and excited-state transitions was achieved by time-dependent density functional theory calculations, which showed good agreement with the experimental results. Using a simple device architecture, we obtained deep red electroluminescence (EL) with high brightness (740 cd m-2) and luminous efficiency of 0.39 cd/A at a low turn-on voltage of 2.5 V. The favorable configuration of the cell consists of only a blend of complexes of indium tin oxide as the anode electrode and molten alloy cathode (Ga/In) without any polymer as the transporting layer. The comparison between [Ru(bpy)3]2+ and [Ru(bpy)3]2+/Zn(DPCO) demonstrates a red shift in the EL wavelength from 625 to 700 nm in the presence of Zn(DPCO), revealing the importance of using blends for future systems.

3.
Iran J Basic Med Sci ; 19(8): 863-869, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27746868

RESUMEN

OBJECTIVES: Several researchers have reported the relationship between infertility in male and varicocele for so many years but the implication of varicocele in female patients is remains elusive. Here, we aim to examine the effects of unilateral varicose ovarian vein on antioxidant capacity and oocyte quality of rat ovary after the experimental creation of varicocele in female rats. MATERIALS AND METHODS: In this study, thirty adult female albino rats were divided into three equal groups: Group 1 as the control group has 10 rats, Group 2 as the sham group has 10 rats and they underwent a sham operation and finally Group 3 has the varicocele group has 10 rats. Antioxidant assays for superoxide dismutase, glutathione peroxidase and catalase were performed using specific assay kits and gene expression for Bax, Bmp-15, Hsp-27 and Gdf-9 was done via real time PCR. RESULTS: The adverse effects of the experimentally induced varicocele were reported and recorded on the left ovary compared to the right sided ovary (no varicocele induction) in the varicocele group. Real time PCR data shows that the expression of Gdf-9, Hsp-27 and Bmp-15 genes were all significantly reduced at p≤ 0.05. CONCLUSION: The results of this study show that reduced gene expression of Bmp-15, Gdf-9 and Hsp-27, increased gene expression of bax and an imbalance between pro-oxidant/antioxidant ratio are few of the several mechanisms by which varicocele may lead to infertility in female.

4.
Int. j. morphol ; 33(4): 1530-1535, Dec. 2015. ilus
Artículo en Inglés | LILACS | ID: lil-772349

RESUMEN

One of the proposed mechanism by which varicocele induces its damage is excessive release of nitric oxide (NO). Several studies have shown the role of NO in poor sperm quality in infertile patients with varicocele. Scientific studies have demonstrated the beneficial effects of curcumin on the sperm parameters. Curcumin as an atoxic antioxidant can reduce production of NO. The aim of this study was to determine the effect of curcumin on NO levels and investigate if curcumin can improve sperm parameters in varicocelized male rats. Thirty male Wistar rats were randomly divided into 5 groups (V1 and V2 (varicocele), T (treatment), Sh (sham) and C was control). In groups V1, V2, T and Sh, the left renal vein was partially ligated to induce varicocele. In groups V1 and V2, sperm parameters and NO level were evaluated 8 and 16 weeks respectively after varicocele induction. Groups T and Sh received 100 mg/kg curcumin and placebo respectively, daily for 8 weeks after 2 months of induced varicocele. Sperm parameters (count, motility, viability and morphology), epididymis and testis weight and also NO concentration were measured. Sperm parameters (count, motility and viability) in groups V1, V2 and Sh were significantly low in comparison with control and treatment groups. The level of NO was significantly increased in serum of rats in groups V1 and V2, whereas group T rat serum in which curcumin was administered, showed decreased NO levels. The values of the epididymis and testis weight had no significant changes (P 0.05) in all groups. Administration of curcumin as a free radical scavenger, can decrease NO level and improve sperm parameters in varicocelized male rats.


Uno de los mecanismos propuestos por el cual los varicoceles inducen daño es la excesiva liberación de óxido nítrico (ON). Varios estudios han demostrado el efecto del ON en la mala calidad del semen en pacientes infértiles con varicocele. Investigaciones han demostrado los efectos beneficiosos de la cúrcuma sobre los parámetros de esperma. La cúrcuma como un antioxidanteatóxico puede reducir la producción de ON. El objetivo de este estudio fue determinar el efecto de la cúrcuma en el nivel de ON e investigar si la cúrcuma puede mejorar los parámetros del semen en ratas macho. Treinta ratas macho Wistar fueron divididas aleatoriamente en 5 grupos (V1y V2 (varicocele), T (tratamiento), Sh (simulado) y C (control)). En los grupos V1, V2, T y Sh, la vena renal izquierda fue parcialmente ligada para inducir varicocele. En los grupos de V1 y V2, los parámetros de semen y nivel de ON se evaluaron a las 8 y 16 semanas respectivamente, después de la inducción de varicocele. Los grupos T y Sh recibieron diariamente 100 mg/kg de cúrcuma y placebo durante 8 semanas, después de 2 meses de inducir el varicocele. Fueron medidos los parámetros del semen (recuento, motilidad, viabilidad y morfología espemática), peso del epidídimo y testículos, junto con la concentración del ON. El recuento, motilidad y viabilidad de los espermatozoides en los grupos V1, V2 y Sh fueron significativamente más bajos en comparación con los grupos C y T. El nivel de ON se incrementó significativamente en el suero de las ratas de los grupos V1 y V2, mientras que el suero del grupo T, en el que se administró cúrcuma, hubo una disminución de los niveles de ON. El peso del epidídimo y testículos tuvieron cambios significativos (P 0,05) en todos los grupos. La administración de cúrcuma como un eliminador de radicales libres, puede disminuir el nivel de ON y mejorar los parámetros espermáticos en ratas macho varicocelizadas.


Asunto(s)
Animales , Ratas , Curcuma/química , Extractos Vegetales/administración & dosificación , Espermatozoides/efectos de los fármacos , Varicocele/tratamiento farmacológico , Óxido Nítrico/análisis , Ratas Wistar , Recuento de Espermatozoides , Espermatozoides/química
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