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1.
Indian J Radiol Imaging ; 28(1): 3-5, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29692517
3.
J Genet ; 96(3): 401-412, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28761005
4.
J Fluoresc ; 27(3): 1171-1181, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28265832

RESUMEN

A novel heterocyclic luminol derivative was synthesized by coupling diazotized 5-aminophthalhydrazide with 2-naphthol. This compound viz., Phthalhydrazide-5-azo-2-naphthol is versatile in forming stable metal complexes with cobalt(II), nickel(II), copper(II) and zinc(II) ions under microwave assisted solvent free conditions. The ligand and the metal complexes were characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, UV-Visible, IR, 1H NMR, and ESR spectral studies wherever possible and applicable. The fluorescence spectra of the ligand and its metal complexes were also recorded. The fluorescence life time measurements were conducted and it was observed that binding of the ligand to the metal ion decreases the average life time of the metal complexes.

5.
J Opt Soc Am A Opt Image Sci Vis ; 32(5): 955-63, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26366922

RESUMEN

Based on an ultrasound-modulated optical tomography experiment, a direct, quantitative recovery of Young's modulus (E) is achieved from the modulation depth (M) in the intensity autocorrelation. The number of detector locations is limited to two in orthogonal directions, reducing the complexity of the data gathering step whilst ensuring against an impoverishment of the measurement, by employing ultrasound frequency as a parameter to vary during data collection. The M and E are related via two partial differential equations. The first one connects M to the amplitude of vibration of the scattering centers in the focal volume and the other, this amplitude to E. A (composite) sensitivity matrix is arrived at mapping the variation of M with that of E and used in a (barely regularized) Gauss-Newton algorithm to iteratively recover E. The reconstruction results showing the variation of E are presented.


Asunto(s)
Módulo de Elasticidad , Tomografía Óptica/métodos , Ondas Ultrasónicas , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 154-61, 2014 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-24051284

RESUMEN

Complexes of manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) with a Schiff base, formed by the condensation of isatin with 2-aminopyrimidine have been synthesised and characterised through elemental analysis, molar conductance measurements, magnetic susceptibility, IR, UV-Vis, (1)HNMR, FAB mass and EPR spectral studies. The spectral data revealed that the ligand acts as neutral bidentate, coordinating to the metal ion through the carbonyl oxygen and azomethine nitrogen. Molar conductance values adequately support the electrolytic nature of the complexes. On the basis of the above observations the complexes have been formulated as [M(ISAP)2]X2, where M=Mn(II), Co(II), Ni(II), Cu(II) and Zn(II); X=Cl, OAc; ISAP=2-[N-indole-2-one]aminopyrimidine. The ligand and copper(II) complex were subjected to X-ray diffraction studies. The DNA cleavage study was monitored by gel electrophoresis method. The superoxide dismutase (SOD) mimetic activities of the ligand and the metal complexes were checked using NBT assay. The in vitro antibacterial activity of the synthesized compounds has been tested against gram negative and gram positive bacteria.


Asunto(s)
Antibacterianos/farmacología , Complejos de Coordinación/síntesis química , División del ADN/efectos de los fármacos , Isatina/química , Pirimidinas/química , Bases de Schiff/síntesis química , Superóxido Dismutasa/metabolismo , Antibacterianos/síntesis química , Antibacterianos/química , Bacterias/efectos de los fármacos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Ligandos , Fenómenos Magnéticos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Bases de Schiff/química , Bases de Schiff/farmacología , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Difracción de Rayos X
8.
Heart Asia ; 6(1): 109-15, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-27326182

RESUMEN

BACKGROUND: Aortic pulse wave velocity (APWV), a marker of arterial stiffness, was found to be a good predictor for the presence of incipient vascular disease and cardiovascular events in observational studies. APWV measured by echo Doppler is a simple and readily available method comparable with other costlier and complex modalities of APWV measurement like MRI, Complior method or applanation tonometry. AIMS AND OBJECTIVES: No previous studies have demonstrated a relationship between APWV findings and the complexity of coronary artery disease (CAD). Our aim was to examine the relationship between APWV findings and the severity of SYNTAX scores (SX scores). METHODS: 500 patients who had undergone APWV measurements and elective coronary angiography from September 2012 to June 2013 were taken. Pulsed Doppler ultrasound (6.6 MHZ) probe with ECG synchronisation was used to calculate APWV. SYNTAX scoring was performed by observers who were blinded to APWV values. RESULTS: A significant, nearly linear correlation between APWV and advancing CAD (p<0.0001) was observed. Patients with dual-vessel and triple-vessel disease had significantly higher APWV than patients without CAD. It was also found that mean APWV values were significantly more in patients with high or intermediate SX scores than in patients with low SX scores. The Fischer's linear discriminant analysis showed a cut-off value of APWV for predicting the possibility of having CAD to be >11.5 m/s. CONCLUSIONS: APWV has predictive value for the SX score. A positive relation exists between aortic stiffening and coronary atherosclerosis and APWV measured by 2D Doppler is a good predictor of advancing CAD.

9.
Heart Asia ; 6(1): 167-71, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-27326198

RESUMEN

BACKGROUND: Early repolarisation (ER) on ECG, which was initially believed to be benign, has of late been considered otherwise. Brugada syndrome has recently been thought to be an extension of the ER spectrum, and the familial tendency of the ER pattern is being highlighted. With attention being drawn to ER's association with idiopathic ventricular fibrillation (VF), the prognosis and lineage of patients with an ER pattern are under scrutiny. AIMS: To analyse ER patterns on ECG, their presence in first-degree relatives and their association with structural heart disease. To classify different types of ER and estimate the prevalence of the high-risk notch/slur pattern in the population studied. METHODS: We screened all patients presenting to our department from December 2011 to July 2014 for ER patterns. We excluded patients with other causes of ST elevation that mimicked the ER pattern, those aged <18 years, and those not willing to participate in the study. A complete physical examination, 12-lead ECG and echocardiography were performed on all study patients. Willing first-degree relatives were screened with a 12-lead ECG. Of the 963 patients with ER that we initially screened, 843 completed the study. A total of 4116 relatives were screened. RESULTS: Of the 843 patients who completed the study, 687 (81.5%) were male and 156 (18.5%) were female. The majority were asymptomatic (70.11%), but had been referred for ECG abnormalities. Fifteen patients with chest pain were inadvertently thrombolysed and were later diagnosed to have ER. Their ER pattern was exaggerated during chest pain, which made this error highly likely. Among the 48 patients who had acute coronary syndrome (ACS), ER pattern was noticed in a different lead than those affected by ACS. Of these, 27 (56.25%) had ventricular tachycardia/VF during the acute phase. Six patients had electrical storm without evidence of ACS, and all had a global ER pattern with prominent notching/slurring on baseline ECG. The most common type of ER pattern was type I (lateral leads; 55.87%). Twenty-one patients had a Brugada pattern. Of all the patients with ER, only a third (34.16%) had the possibly high-risk notched/slurred ECG pattern. The majority (82.92%) had a structurally normal heart. We found that mitral valve prolapse (MVP), as assessed by >2 mm leaflet prolapse from the annulus, was more common in patients with ER (11.39%). Of the 4116 relatives screened, 2625 (63.78%) had an ER pattern; a quarter of family members had the inferolateral variety and over 60% of relatives had the lateral variety. We also noticed different ER patterns in the same family. CONCLUSIONS: We found that exaggeration of the ER pattern during chest pain may lead to inadvertent thrombolysis. A notched/slurred ER pattern is found in only a third of patients, who need to be grouped separately, as they may constitute a high-risk category. Patients with ER had MVP at a higher prevalence (almost double) than the general population, probably explaining the high incidence of sudden cardiac death associated with MVP. A familial tendency to an ER pattern was found in more than half of first-degree relatives, with different ER patterns, even the Brugada pattern, found in the same family. This may be because Brugada and other ER patterns belong to the same spectrum and may share the same prognosis. Thus we conclude that further studies regarding ER, its association with MVP, risk stratification by notched ECG pattern, and familial distribution along with gene analysis are warranted.

10.
Artículo en Inglés | MEDLINE | ID: mdl-19910244

RESUMEN

Complexes of manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) with a novel heterocyclic azo derivative, formed by coupling diazotized 2-amino-3-carbethoxy-4,5-dimethylthiophene with acetylacetone were synthesized and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility measurements, UV-vis, IR, (1)H NMR and EPR spectral data. Spectral studies revealed that the ligand existed in an internally hydrogen bonded azo-enol form rather than the keto-hydrazone form and coordinated to the metal ion in a tridentate fashion. Analytical data revealed that all the complexes exhibited 1:1 metal-ligand ratio. On the basis of electronic spectral data and magnetic susceptibility measurements, suitable geometry was proposed for each complex. The nickel(II) complex has undergone facile transesterification reaction when refluxed in methanol for a long period. The ligand and the copper(II) complex were subjected to X-ray diffraction study. The electrochemical behaviour of copper(II) complex was investigated by cyclic voltammetry. The thermal behaviour of the same complex was also examined by thermogravimetry.


Asunto(s)
Compuestos Azo/química , Electroquímica , Elementos de Transición/química , Cobalto/química , Cobre/química , Espectroscopía de Resonancia por Spin del Electrón , Ligandos , Espectroscopía de Resonancia Magnética , Manganeso/química , Estructura Molecular , Níquel/química , Temperatura , Termogravimetría , Difracción de Rayos X , Zinc/química
11.
Artículo en Inglés | MEDLINE | ID: mdl-18165148

RESUMEN

Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes with a potentially tridentate Schiff base, formed by condensation of 2-amino-3-carboxyethyl-4,5-dimethylthiophene with salicylaldehyde were synthesized and characterized on the basis of elemental analyses, molar conductance values, magnetic susceptibility measurements, UV-vis, IR, EPR and NMR spectral data, wherever possible and applicable. Spectral studies reveal that the free ligand exists in a bifunctionally hydrogen bonded manner and coordinates to the metal ion in a tridentate fashion through the deprotonated phenolate oxygen, azomethine nitrogen and ester carbonyl group. On the basis of electronic spectral data and magnetic susceptibility measurements, suitable geometry has been proposed for each complex. The EPR spectral data of the Cu(II) complex showed that the metal-ligand bonds have considerable covalent character. The Ni(II) complex has undergone facile transesterification reaction when refluxed in methanol for a lengthy period. X-ray diffraction studies of Cu(II) complex showed that the complex has an orthorhombic crystal lattice. In view of the biological activity of thiophene derivatives, the ligand and the complexes were subjected to antibacterial screening. It has been observed that the antibacterial activity of the ligand increased on chelation with metal ion.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Tiofenos/síntesis química , Tiofenos/farmacología , Elementos de Transición/síntesis química , Elementos de Transición/farmacología , Antibacterianos/química , Bacterias/efectos de los fármacos , Electroquímica , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Esterificación/efectos de los fármacos , Ligandos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Compuestos Organometálicos/química , Espectrofotometría Infrarroja , Tiofenos/química , Elementos de Transición/química , Difracción de Rayos X
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