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The first example of trinuclear copper(I) and silver(I) pyrazolates adducts with a tertiary diphosphine (Ph2PCH2PPh2) retaining trimeric [MPz]3 core is reported. Despite rather strong M-P bonding, the complexes are able to undergo the dissociation of one M-P bond leading to the "merry-go-round" movement of P atoms over the M3 triangle. The copper complex displays emission from 1MLCT and 3MLCT states. The triplet and singlet states are separated by a relatively small energy gap (1080 cm-1) that triggers the thermally activated delayed fluorescence (TADF) behavior and leads to the worthy quantum yield of 41% at 298 K. The silver complex in the solid state and frozen solution shows dual emission originating from the 1IL and 3MLCT states that is dictated by the much higher energy difference between the emissive singlet and triplet as well as by the essentially different nature of these states.
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BACKGROUND: While various biomaterials are used for bone regeneration, the relative comparative efficiency of them has not been thoroughly investigated. PURPOSE: This study evaluated histopathological events during osseous healing after implantation of following bone grafts: Demineralized freeze-dried cortical bone powder (DFDB), natural coral implants, calcium sulfate-based putty containing demineralized bone matrix (CaS-DBM), and pure-phase beta tricalcium phosphate ceramic granules (ß-TCP). MATERIALS AND METHODS: Fifty-six Wistar Albino rats were used for this study. The postimplantation osseous healing was evaluated at 3rd, 6th weeks after the operation. RESULTS: DFDB did not induce bone formation in 3 weeks period, but it showed a highly osteoinductive effect at the end of 6th week period. The effects of coral implants on bone formation both at 3 and 6 weeks period were much higher than the DFDB. CaS-DBM showed higher bone formation than ß-TCP at 3rd, 6th weeks. It was found that coral and CaS-DBM had a more beneficial impact on early bone healing compared to ß-TCP and DFDB. All these graft biomaterials are useable in human bone defects. The main difference in the ossous healing properties of these materials is observed early postimplantation with the delayed healing outcome being similar.
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Materiales Biocompatibles , Regeneración Ósea , Trasplante Óseo , Animales , Fosfatos de Calcio , Cerámica , Humanos , Osteogénesis , Ratas Wistar , Cicatrización de HeridasRESUMEN
A novel supramolecular [Au6Cu2(C2C6H4-4-COONC4H4O2)6(Ph2PC6H4PPh2)3](PF6)2 complex functionalized with a succinimide ester alkynyl substituent has been synthesized and characterized using X-ray crystallography, mass spectrometry, and NMR spectroscopy. Like the other complexes of this class, it demonstrates bright emission in acetone and dichloromethane solutions with the excited state lifetime in a microsecond domain. This complex readily reacts with a surface amine group of proteins/enzymes (human serum albumin (HSA), rabbit anti-HSA antibodies, soybean trypsin inhibitor, and α-chymotrypsin) to give covalent conjugates, which contain up to five molecules of the luminescent label bound to the biomolecule. The conjugates keep a high level of the phosphorescent label emission, but in contrast to the parent complex molecule, display excellent solubility and high stability in physiological media. Investigation of the biological activity of the conjugates also showed that the specific structure of the biomolecules remained nearly unchanged upon bonding with the label, which is indicative of a very prospective of the conjugates application in biomolecular detection.
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Cobre/química , Oro/química , Mediciones Luminiscentes/métodos , Proteínas/química , Animales , Anticuerpos/química , Técnicas de Química Sintética , Quimotripsina/química , Cristalografía por Rayos X , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Conejos , Albúmina Sérica/química , Albúmina Sérica/inmunología , Succinimidas/químicaRESUMEN
The combined action of ultraviolet irradiation and microwave heating onto acetonitrile solution of [Re( NN )(CO)3 (NCMe)]OTf ( NN =phenantroline and neocuproine) afforded cis,trans-Re( NN )(CO)2 (NCMe)2 ]+ acetonitrile derivatives. Substitution of relatively labile NCMe with a series of aromatic N-donor ligands (pyridine, pyrazine, 4,4'-bipyridine, N-methyl-4,4'-bipyridine) gave a novel family of the diimine cis,trans-[Re( NN )(CO)2 (L)2 ]+ complexes. Photophysical studies of the obtained compounds in solution revealed unusually high absorption across the visible region and NIR phosphorescence with emission band maxima ranging from 711 to 805â nm. The nature of emissive excited states was studied using DFT calculations to show dominant contribution of 3 MLCT (dπ(Re)âπ*( NN )) character. Electrochemical (CV and DPV) studies of the monocationic diimine complexes revealed one reduction and one oxidation wave assigned to reduction of the diimine moiety and oxidation of the rhenium center, respectively.
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The growing attention to the luminescent nanocarriers is strongly stimulated by their potential application as drug delivery systems and by the necessity to monitor their distribution in cells and tissues. In this communication we report on the synthesis of amphiphilic polypeptides bearing C-terminal phosphorescent label together with preparation of nanoparticles using the polypeptides obtained. The approach suggested is based on a unique and highly technological process where the new phosphorescent Pt-cysteine complex serves as initiator of the ring-opening polymerization of α-amino acid N-carboxyanhydrides to obtain the polypeptides bearing intact the platinum chromophore covalently bound to the polymer chain. It was established that the luminescent label retains unchanged its emission characteristics not only in the polypeptides but also in more complicated nanoaggregates such as the polymer derived amphiphilic block-copolymers and self-assembled nanoparticles. The phosphorescent nanoparticles display no cytotoxicity and hemolytic activity in the tested range of concentrations and easily internalize into living cells that makes possible in vivo cell visualization, including prospective application in time resolved imaging and drug delivery monitoring.
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Sustancias Luminiscentes/química , Nanopartículas del Metal/química , Péptidos/química , Línea Celular Tumoral , Cisteína/química , Células HEK293 , Hemólisis/efectos de los fármacos , Humanos , Sustancias Luminiscentes/síntesis química , Nanopartículas del Metal/efectos adversos , Péptidos/síntesis química , Platino (Metal)/química , Polimerizacion , Tensoactivos/síntesis química , Tensoactivos/químicaRESUMEN
A novel type of cyclic P,N-ligands, pyridyl containing phospholanes, has been synthesized in a moderate yield by the reaction of primary phosphines with 1,4-dichlorobutane in a superbasic medium. A series of homo tetranuclear octahedral Cu4I4L2, dinuclear tetrahedral Cu2I2L3, and dinuclear "head-to-tail" Cu2I2L2 luminescent complexes with these ligands were obtained. All the compounds were characterized using a range of spectroscopic and computational techniques, and in the case of some Cu4I4L2 and Cu2I2L3 complexes, by single crystal X-ray diffraction. The structural diversity of the obtained complexes was reflected in their photophysical properties: phosphorescence spectra of the compounds display emission in broad spectral range of 471-615 nm. TD-DFT computations allow the assignment of a single emission band around 550 nm for Cu2I2L3 complexes and 471 nm for Cu2I2L2 complex to a vertical triplet-singlet transition from a metal-to-ligand and halide-to-ligand charge-transfer (3)(M + X)LCT excited state, whereas a second band at around 600 nm in the spectra of octahedral Cu4I4L2 complexes was assigned predominantly to Cu4I4 cluster-centered ((3)CC) excited state.
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OBJECTIVE: To investigate the combined effect of rosuvastatin and ischemic preconditioning or postconditioning on ischemia-reperfusion injury in in vivo rat heart. MATERIALS AND METHODS: Ninenty-six male adult Wistar rats were randomly assigned to eight groups: Sham group, ischemia-reperfusion, rosuvastatin preconditioning, rosuvastatin postconditioning, ischemic preconditioning, ischemic postconditioning, ischemic + pharmacologic preconditioning and ischemic + pharmacologic postconditioning groups. Blood samples were taken for creatine kinase evaluation at selected time points. Six rats in each group were separated for either infarct size assessment or immunohistochemical staining with Bcl-2 antibody. RESULTS: The staining with Bcl-2 was significantly lower in groups Sham, ischemic + pharmacologic preconditioning and ischemic + pharmacologic postconditioning groups which is well correlated with the decrease in infarct size for the same groups. The creatine kinase enzyme levels were also reduced to their lowest levels in ischemic + pharmacologic preconditioning and ischemic + pharmacologic postconditioning groups. CONCLUSIONS: These findings suggest that enriching the composition of reperfusate with rosuvastatin along with ischemic preconditioning or postconditioning procedures at the opposite sides of ischemia may interact synergistically for protecting ischemic myocardium from reperfusion injury. The combined application of rosuvastatin with ischemic preconditioning or ischemic postconditioning may provide a new therapeutic option in clinical interventions when compared to single treatment with ischemic and rosuvastatin preconditioning or postconditioning.
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Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Poscondicionamiento Isquémico/métodos , Precondicionamiento Isquémico Miocárdico/métodos , Daño por Reperfusión Miocárdica/terapia , Rosuvastatina Cálcica/administración & dosificación , Animales , Terapia Combinada/métodos , Masculino , Daño por Reperfusión Miocárdica/patología , Ratas , Ratas Wistar , Resultado del TratamientoRESUMEN
A series of square planar [Pt(N^C)(NHC)L] complexes containing cyclometallated N^C ligands (phenylpyridine and benzoquinoline) and N-heterocyclic carbene (NHC)--N^C = 2-phenylpyridine, 7,8-benzoquinoline; NHC = 1,3-dibenzylbenzimidazolium, 1,3-diethylbenzimidazolium, 1,3-dibenzylimidazolium; L = Cl, Br, -C2Ph--have been synthesized in moderate to good yields. The complexes obtained were characterized using chemical analysis, MS-ESI spectrometry, NMR spectroscopy and X-ray crystallography. The complexes display moderate to strong phosphorescence in solution (Q.Y. 0.3-7.9%) and in the solid state (Q.Y. 2.7-16.0%), which is related to metal modulated intraligand π-π* transitions located at the aromatic system of cyclometallated ligands with some contribution of the MLCT excited state. Emission lifetimes fall in the range of 0.2-1.5 µs in solution and amount up to 13 µs in the solid state. Analysis of the spectroscopic data together with the density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations clearly support this assignment and show negligible contribution of the auxiliary ligands to the emissive excited states. The compounds obtained were also used to prepare organic light emitting diode (OLED) devices, which display good luminance efficiency emitting in the green area of the visible spectrum.
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Micro-chips based on organic-inorganic hybrid nanoparticles (NPs) composed of nanoalloys of gold (Au) and silver (Ag) embedded in an amorphous carbonaceous matrix (C-Au-Ag NPs) were prepared directly on a substrate by the laser-induced deposition (for short: LID) method. The C-Au-Ag NPs show a unique plasmon resonance which enhances Raman scattering of analytes, making the µ-chips suitable to detect ultra-low-volumes (10(-12) liter) and concentrations (10(-9) M) of bio-agents and a hazardous compound. These micro-chips constitute a novel, flexible solid-state device that can be used for applications in point-of-care diagnostics, consumer electronics, homeland security and environmental monitoring.
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Oro/química , Nanopartículas del Metal/química , Análisis por Micromatrices/instrumentación , Nanotecnología/métodos , Plata/química , Diseño de Equipo , Espectrometría RamanRESUMEN
In the present work an efficient approach of the controlled formation of hybrid Au-Ag-C nanostructures based on laser-induced transformation of organometallic supramolecular cluster compound is suggested. Herein the one-step process of the laser-induced synthesis of hybrid multi-yolk-shell Au-Ag@a-C:H nanoparticles which are bimetallic gold-silver subnanoclusters dispersed in nanospheres of amorphous hydrogenated a-C:H carbon is reported in details. It has been demonstrated that variation of the experimental parameters such as type of the organometallic precursor, solvent, deposition geometry and duration of laser irradiation allows directed control of nanoparticles' dimension and morphology. The mechanism of Au-Ag@a-C:H nanoparticles formation is suggested: the photo-excitation of the precursor molecule through metal-to-ligand charge transfer followed by rupture of metallophilic bonds, transformation of the cluster core including red-ox intramolecular reaction and aggregation of heterometallic species that results in the hybrid metal/carbon nanoparticles with multi-yolk-shell architecture formation. It has been found that the nanoparticles obtained can be efficiently used for the Surface-Enhanced Raman Spectroscopy label-free detection of human serum albumin in low concentration solution.
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Rayos Láser , Nanoestructuras/química , Carbono/química , Oro/química , Humanos , Hidrógeno/química , Nanoestructuras/ultraestructura , Espectroscopía de Fotoelectrones , Albúmina Sérica/análisis , Plata/química , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría RamanRESUMEN
Ovarian mucinous tumors stem from ovarian surface epithelium and are divided into benign, borderline and malignant. It is difficult to differentiate borderline and malignant mucinous tumors. Thirty-eight cases of ovarian mucinous tumors which were diagnosed at the Pathology Department of Dicle University Medical Faculty were reviewed. Of these, 18 (47.3%), six (15.7%) and 14 (36.8%) were benign, borderline and malignant, respectively. The patients' ages ranged from 18 to 67 (average 44.5) years. Bilaterality was detected in 1/18 (5.5%), 0/6 and 4/14 (28.5%) of benign, borderline and malignant mucinous tumors, respectively. Mean tumor size was 26.4 cm. Microscopically, there was no stratification in the benign tumors. The borderline tumors had papillary infoldings and 2-3 layers of atypical epithelial cells but no invasion of the stroma. Malignant tumors had four or more layers of atypical epithelial cells and stromal invasion.
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Adenocarcinoma Mucinoso/diagnóstico , Neoplasias Ováricas/diagnóstico , Adenocarcinoma Mucinoso/patología , Adulto , Distribución por Edad , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/patología , Pronóstico , Índice de Severidad de la EnfermedadRESUMEN
Novel water-soluble noncovalent adducts of the heterometallic copper subgroup complexes and human serum albumin (HSA) display strong phosphorescence, internalize into HeLa cells and can be used in time-resolved fluorescent imaging.
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Complejos de Coordinación/química , Cobre/química , Oro/química , Plata/química , Complejos de Coordinación/metabolismo , Cobre/metabolismo , Oro/metabolismo , Células HeLa , Humanos , Luminiscencia , Albúmina Sérica/química , Albúmina Sérica/metabolismo , Plata/metabolismo , Solubilidad , Agua/químicaRESUMEN
BACKGROUND AND AIMS: Diabetes Mellitus, leading to an increase in oxidative stress, can cause liver damage. Our aim was to investigate the antioxidant effects of Ethyl Pyruvate (EP) on the liver tissue in diabetic rats. MATERIALS AND METHODS: Thirty-two Wistar albino rats were separated into four equal groups. Groups were assigned as follows: (1) Non-diabetic group; (2) EP-treated non-diabetic group; (3) diabetic group; and (4) EP-treated diabetic group. In order to induce diabetes mellitus, 45 mg/kg b.w. streptozotocin was administered intraperitoneally to the rats in groups 3 and 4. On the 3rd day, blood glucose was assessed. Rats with blood glucose levels higher than 300 mg/dl were considered to be diabetic. The EP solution was administered intraperitoneally at a dose of 50 mg/kg b.w. twice daily for 14 days to the rats in groups 2 and 4. The other rats were simultaneously given the same amount of Ringer's lactate solution intraperitoneally. Liver tissue was obtained for malondialdehyde (MDA) analyses and histopathological examination. RESULTS: In group 4, Total Antioxidant Status (TOS) and MDA levels were significantly lower as compared to group 3. Also, morphological abnormalities occurred in group 3 when compared with non-diabetic groups (groups 1 and 2), whereas the disorders resulting from diabetes improved significantly in group 4. CONCLUSIONS: These findings show that EP has protective effects against diabetes-induced liver injury.
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Diabetes Mellitus Experimental/complicaciones , Piruvatos/uso terapéutico , Animales , Hepatocitos/patología , Hepatocitos/ultraestructura , Hígado/ultraestructura , Masculino , Malondialdehído/análisis , Estrés Oxidativo/efectos de los fármacos , Piruvatos/farmacología , Ratas , Ratas Wistar , EstreptozocinaRESUMEN
The purpose of this study was to investigate the ultrastructural effects of lead on the kidney cortex of rats. Wistar Albino rats (180-200g body weight) were divided into a controlled and lead acetate-exposed group. Rats received lead acetate at 500 ppm in their drinking water for 60 days. Both groups were fed with the same standard food, but lead acetate was added to the drinking water. During the experimental period, blood samples were taken from the abdominal aorta of the anesthetised animals. At the end of exposure, body weight and blood lead levels were measured. The kidney tissue samples were prepared and analyzed by light and transmission electron microscopy. Cortical renal tubules show various degenerative changes with focal tubular necrosis invaded by inflammatory cells. The ultrastructural alterations found in lead acetate-treated rats were a diminution in the amount of filtration slits, increased fusion of foot processes in epithelial cells of the glomeruli, increase of lysosomal structures and pinocytic vesicles as well as large mitochondria in proximal tubule cells.
El propósito de este estudio fue investigar los efectos ultraestructurales del plomo en la corteza renal. Ratas Wistar albinas (180-200g de peso corporal) fueron divididas en grupo control y grupo experimental. Las ratas recibieron 500 ppm de acetato de plomo en el agua potable durante 60 días. Ambos grupos fueron alimentados con el mismo alimento estándar, pero acetato de plomo se le añadió al agua potable al grupo experimental. Durante el período experimental, se tomaron bajo anestesia muestras sanguíneas desde la parte abdominal de la aorta. Al final de la exposición, fueron medidos el peso corporal y los niveles de plomo en la sangre. Fueron preparadas las muestras de tejido renal y se analizaron mediante microscopía de luz y electrónica de transmisión. Los túbulos renales corticales mostraron varios cambios degenerativos con necrosis tubular focal invadida por células inflamatorias. Las alteraciones ultraestructurales encontradas en las ratas tratadas con acetato de plomo correspondieron a una disminución en la cantidad de ranuras de filtración, aumento de la fusión de los procesos podales en las células epiteliales de los glomérulos, aumento de la estructura lisosomal y las vesículas pinocíticas, así como grandes mitocondrias en las células del túbulo proximal.
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Ratas , Corteza Renal/anatomía & histología , Corteza Renal , Corteza Renal/irrigación sanguínea , Corteza Renal/lesiones , Corteza Renal/ultraestructura , Plomo/administración & dosificación , Plomo/fisiología , Plomo/sangre , Plomo/toxicidad , Acetatos/efectos adversos , Acetatos/sangre , Acetatos/toxicidad , Ratas Wistar/anatomía & histología , Ratas Wistar/lesiones , Ratas Wistar/sangreRESUMEN
Multiple-metal spin transitions which distort the HMQC spectra of rhodium carbonyl clusters are discussed. These effects are seen whenever the detector nucleus, e.g. 13C or 31P, couples to more than one metal spin and are not restricted to detector ligands occupying edge- or face-bridging sites. These effects are illustrated in, but not limited to, the 13C-{103Rh} and 31P-{103Rh} HMQC spectra of [Rh6(CO)15L], (where L = P(4-F-C6H4)3), [Rh4(CO)11{P(OPh)3}], [Rh6C(CO)15]2- and [Rh2(carboxylate)2PPh3]. The effect is to modulate the intensity and position of the correlations in the metal dimension; cross peaks are displaced from the true chemical shift, additional cross peaks are seen and the intensity of the coherences varies as a function of the preparation delay, d2, and coupling constant, and may go to zero at the conventional value of 1/(2J). Analyses of the relevant spin systems are given together with experimental strategies to overcome these effects.