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1.
Science ; 332(6030): 698-702, 2011 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-21527674

RESUMEN

The high-temperature superconducting cuprate La(2-x)Sr(x)CuO(4) (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2p(x)/p(y) orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials.

2.
J Phys Chem B ; 111(21): 6042-50, 2007 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-17488111

RESUMEN

A new target in AIDS therapy development is HIV-1 integrase (IN). It was proven that HIV-1 IN required divalent metal cations to achieve phosphodiester bond cleavage of DNA. Accordingly, all newly investigated potent IN inhibitors contain chemical fragments possessing a high ability to chelate metal cations. One of the promising leads in the polyhydroxylated styrylquinolines (SQLs) series is (E)-8-hydroxy-2-[2-(4,5-dihydroxy-3-methoxyphenyl)-ethenyl]-7-quinoline carboxylic acid (1). The present study focuses on the quinoline-based progenitor (2), which is actually the most probable chelating part of SQLs. Conventional and synchrotron low-temperature X-ray crystallographic studies were used to investigate the chelating power of progenitor 2. Mg2+ and Cu2+ cations were selected for this purpose, and three types of metal complexes of 2 were obtained: Mg(II) complex (4), Cu(II) complex (5) and mixed Mg(II)-Cu(II) complexes (6 and 7). The analysis of the crystal structure of complex 4 indicates that two tridentate ligands coordinate two Mg2+ cations, both in octahedral geometry. The Mg-Mg distance was found equal to 3.221(1) A, in agreement with the metal-metal distance of 3.9 A encountered in the crystal structure of Escherichia coli DNA polymerase I. In 5, the complex is formed by two bidentate ligands coordinating one copper ion in tetrahedral geometry. Both mixed Mg(II)-Cu(II) complexes, 6 and 7 exhibit an original arrangement of four ligands linked to a central heterometallic cluster consisting of three octahedrally coordinated magnesium ions and one tetrahedrally coordinated copper ion. Quantum mechanics calculations were also carried out in order to display the electrostatic potential generated by the dianionic ligand 2 and complex 4 and to quantify the binding energy (BE) during the formation of the magnesium complex of progenitor 2. A comparison of the binding energies of two hypothetical monometallic Mg(II) complexes with that found in the bimetallic magnesium complex 4 was made.


Asunto(s)
Cobre/química , Inhibidores de Integrasa VIH/química , Magnesio/química , Compuestos Organometálicos/química , Quinolinas/química , Simulación por Computador , Cristalización , Cristalografía por Rayos X , Electrones , Inhibidores de Integrasa VIH/síntesis química , Enlace de Hidrógeno , Modelos Químicos , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química , Teoría Cuántica , Electricidad Estática
3.
Gynecol Obstet Fertil ; 31(7-8): 629-38, 2003.
Artículo en Francés | MEDLINE | ID: mdl-14563609

RESUMEN

The objective was to investigate women's perceptions and the perceived stress experience when undergoing surveillance mammography for benign lesions (ACR3, BI-RADS). A semi-prospective study was carried out on women with diagnosed "probably benign" breast abnormalities. It was a multicentric study from 1st March to 10th June 2002. The survey was performed at the first follow-up mammography and included questions about perceptions and perceived stress related to the follow-up experience. The response is analysed with chi-square test. Fifty women (35-75 years) answered the questionnaire. All women were satisfied with reception. The mammographies were painful (23 cases). Subsequent time seemed to be too long (seven cases) and they were anxious in 19 cases. Quality of life was spoiled (disturbed) (20 cases). Professional and social perturbations were not frequent (four cases). Speaking to a relative is frequent (39 cases), but patients were not satisfied with it (33 cases). Medical information was estimated (47 cases) but was not satisfactory (36 cases). The median of the stress scale is 4-5. There are two pickaxes, one at 2 (11 cases), the second at 5 (8 cases). "Low-stressed" women could have an avoidance coping. "High-stressed" women could use a helplessness- hopelessness coping strategy. Women reported a good and informative medical support and adequate comprehension of the short follow-up mammography. They were reassured by the medical care, but the evaluation of the stress level shows it to be high, probably due to the uncertainty of diagnosis.


Asunto(s)
Mamografía/psicología , Estrés Psicológico/epidemiología , Adaptación Psicológica , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Dolor , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios , Factores de Tiempo
4.
Ann Cardiol Angeiol (Paris) ; 35(4): 195-8, 1986 Apr.
Artículo en Francés | MEDLINE | ID: mdl-3090925

RESUMEN

Clinical safety and hemodynamic repercussions were studied after administration of six class I antiarrhythmics (xylocaine, ajmaline, mexiletine, lorcainide, indecainide and tocainide) to patients presenting acute myocardial infarction without complications. The hemodynamic parameters monitored generally followed the same trends. A significant decrease of more than 10 per cent of the initial value was seen in systolic blood flow after injection of lorcainide, indecainide and tocainide. Peripheral vascular resistance increased moderately. Pulmonary capillary pressure increased by more than 40 per cent of the starting value after administration of mexiletine, indecainide and tocainide (significant increase in case of mexiletine). These changes in patients presenting infarction without complications are not of clinical importance. There were, however, two very severe cases of hemodynamic reaction after administration of mexiletine. Other signs of intolerance were seen, but they were of minor importance and administration of the drugs was not interrupted. Xylocaine and ajmaline produced the smallest depression of left ventricular functional activity in these patients.


Asunto(s)
Antiarrítmicos/uso terapéutico , Bencenoacetamidas , Hemodinámica/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológico , Ajmalina/uso terapéutico , Antiarrítmicos/efectos adversos , Antiarrítmicos/farmacología , Fluorenos/uso terapéutico , Lidocaína/análogos & derivados , Lidocaína/uso terapéutico , Mexiletine/uso terapéutico , Infarto del Miocardio/fisiopatología , Piperidinas/uso terapéutico , Tocainida
5.
Bull Soc Pathol Exot Filiales ; 76(5): 584-7, 1983 Nov.
Artículo en Francés | MEDLINE | ID: mdl-6370479

RESUMEN

Immunomodulators, whether natural (polysaccharides) or industrial (non-hemolytic detergents) proved active by themselves, in preventive or curative schemes of experimental leprosy and malaria. However, their activity was most often increased, through joint administration with chemotherapeutic agents.


Asunto(s)
Lepra/tratamiento farmacológico , Malaria/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Femenino , Glucanos/uso terapéutico , Lepra/inmunología , Lepra/veterinaria , Malaria/inmunología , Malaria/veterinaria , Ratones , Ratones Endogámicos , Plasmodium berghei , Polietilenglicoles/uso terapéutico , Tensoactivos/uso terapéutico
6.
Exp Parasitol ; 56(2): 190-3, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6413237

RESUMEN

alpha-Difluoromethylornithine (DFMO), an enzyme inhibitor of ornithine decarboxylase, inhibits the sporogonous cycle of the malaria parasite Plasmodium berghei in the mosquito vector Anopheles stephensi. DFMO was administered to the mosquitoes dissolved either in the sugar solution at their disposal in the cages or through blood meals taken from treated mice. The mice subsequently bitten by mosquitoes treated with DFMO by both routes of administration did not contract malaria.


Asunto(s)
Anopheles/parasitología , Inhibidores de la Ornitina Descarboxilasa , Ornitina/análogos & derivados , Plasmodium berghei/efectos de los fármacos , Animales , Eflornitina , Ornitina/farmacología , Plasmodium berghei/crecimiento & desarrollo
9.
Acta Cardiol Suppl ; (25): 75-80, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6966455

RESUMEN

Intravenous mexiletine (250 mg in 10 min) given to patients at the acute stage of a myocardial infarction was responsible of a mild decrease of the left ventricular function; two of our patients presented bradycardia with hypotension, immediately corrected by atropine (i.v.). Adverse hemodynamic effects are seldom reported after oral administration.


Asunto(s)
Hemodinámica/efectos de los fármacos , Mexiletine/farmacología , Propilaminas/farmacología , Administración Oral , Humanos , Inyecciones Intravenosas , Mexiletine/administración & dosificación , Factores de Tiempo
10.
Acta Cardiol ; 33(5): 323-9, 1978.
Artículo en Francés | MEDLINE | ID: mdl-312574

RESUMEN

The authors describe 2 cases of Kearns-Sayre Syndrome associated with conduction defects. In one case permanent pacing was performed. The progressive development of severe conduction defects warrants close follow-up.


Asunto(s)
Bloqueo Cardíaco/complicaciones , Oftalmoplejía/complicaciones , Retinitis Pigmentosa/complicaciones , Adolescente , Femenino , Humanos , Síndrome
11.
Cardiology ; 62(4-6): 291-5, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-589611

RESUMEN

A triple human catheter was used for the determination of cardiac output during the acute phase of moycardial infarction in 23 patients. The correlation coefficient between thermodilution and the Fick method was 0.91. Precision of the method assessed by multiple repeated determinations was 4.8 or 5.6%. Quadruplicate determinations allowed to detect variations of cardiac output in the range of 0.465 1/min. Variation between two successive determinations of more than 9.4% can probably be attributed to a technical error.


Asunto(s)
Gasto Cardíaco , Monitoreo Fisiológico/métodos , Infarto del Miocardio/diagnóstico , Termodilución/métodos , Enfermedad Aguda , Análisis de Varianza , Humanos , Infarto del Miocardio/fisiopatología
12.
J Radiol Electrol Med Nucl ; 56(12): 887-90, 1975 Dec.
Artículo en Francés | MEDLINE | ID: mdl-1214239

RESUMEN

From this analysis of a series of 39 cases of trauma submitted to angiography, it can once again be said that surgical indications and tactics are essentially determined by vascular involvment. Renal arteriography is therefore alone capable of answering two primordial questions: "Must surgery be undertaken and when operating, what surgical tactics to adopt". It must be preceded by full arteriography which enables one to evaluate associated lesions (spleen 15%), at the same time as it orientates selective arteriography. The I.V.P. is a correct means of approach but is only significant in 60% of cases. Abstention from radiological investigation as a primary requisite is unpardonable and can leave irreversible sequels. (10% of cases).


Asunto(s)
Angiografía , Riñón/lesiones , Traumatismos Abdominales/diagnóstico por imagen , Niño , Hematuria/etiología , Humanos , Arteria Renal/diagnóstico por imagen , Urografía
13.
J Radiol Electrol Med Nucl ; 56(2): 173-4, 1975 Feb.
Artículo en Francés | MEDLINE | ID: mdl-1151915

RESUMEN

The authors report a case of hypertension due to dysplasia of the renal arteries in a young man, and found the same disease in siblings. Two sisters and one brother also had renal hypertension, whereas the other relatives were unaffected. Two similar cases found in the world literature, did not permit the authors to determine the cause of this disease. This case is reported in order to stimulate research and the discovery of new cases.


Asunto(s)
Hipertensión Renal/genética , Arteria Renal/anomalías , Adulto , Aortografía , Humanos , Hipertensión Renal/etiología , Enfermedades Renales/genética , Masculino , Arteria Renal/diagnóstico por imagen , Arteria Renal/cirugía , Obstrucción de la Arteria Renal/complicaciones
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