RESUMEN
A new rapid protocol for 226Ra separation and preconcentration in natural water samples was developed before its determination by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). For this purpose, the commercially available Ra specific resin AnaLig® Ra-01 was used. This resin shows a high selectivity for radium in a large range of acid concentrations and no affinity or possible elution of 226Ra interfering elements. The distribution coefficients of Ra and other elements over a wide range of acid (HCl and HNO3) concentrations were obtained. Due to the high radium selectivity, the new developed protocol uses only 50â¯mg of dry resin and its performance was evaluated using 100â¯mL of three natural waters with different ionic strengths, spiked with a known quantity of 226Ra. Radium was successfully separated and preconcentrated yielding recoveries ranging between 72% and 86%. In parallel with the characterisation of the resin sorption properties, a detailed study of polyatomic interferences was performed on our ICP-MS allowing to identify the prominent elements favouring interferences at m/zâ¯=â¯226. Furthermore, a 226Ra sensitivity comparison between different ICP-MS instruments and configurations was done in order to determine high sensitivity conditions for radium analysis.
Asunto(s)
Radio (Elemento)/análisis , Contaminantes Radiactivos del Agua/análisis , Espectrofotometría Atómica , Análisis EspectralRESUMEN
BACKGROUND: Coronary artery disease (CAD) may be present in kidney transplant (KT) candidates without the presence of CAD clinical symptoms. This study joins an ongoing discussion about appropriate noninvasive diagnostic approaches for ischemic heart disease (IHD) assessment and patient selection for revascularization procedures. The aim of this study was to evaluate the role of dobutamine stress echocardiography (DSE) in IHD diagnosis in initially asymptomatic maintenance hemodialysis (HD) patients. METHODS: Forty HD patients aged 52.4 ± 2.0 years, were studied for 2.5 years. At inclusion, they were free of both symptoms and history of IHD. Standard electrocardiography (ECG), chest X-ray, standard echocardiography, DSE, 24-hour Holter ECG, and Doppler ultrasonography (carotids and lower extremities) were performed. Results were analyzed according to a predefined diagnostic algorithm. RESULTS: DSE yielded negative results in all patients. Left ventricular (LV) ejection fraction ≤ 60%, LV hypertrophy, and Holter ECG silent ischemia features were noticed in 15%, 70%, and 10% of patients, respectively. Atherosclerotic lesions in lower extremities and carotid arteries were present in 50% and 37.5% of patients, respectively. During the follow-up, 9/40 patients died, including 6 cardiovascular (CV) deaths: 2 with intermediate and 4 with high CV risk according to the proposed algorithm. CONCLUSIONS: In asymptomatic KT candidates, not only DSE, but also other noninvasive tests (eg, echocardiography and Doppler ultrasonography of the carotid and peripheral arteries) along with a detailed profile of the remaining CV risk factors should be performed and analyzed. Defined composition of risk factors and particular changes in noninvasive tests may be an indication for coronary angiography.
Asunto(s)
Enfermedades Asintomáticas , Ecocardiografía de Estrés , Isquemia Miocárdica/diagnóstico , Insuficiencia Renal Crónica/complicaciones , Arterias Carótidas/diagnóstico por imagen , Angiografía Coronaria , Ecocardiografía , Electrocardiografía , Femenino , Pruebas de Función Cardíaca , Humanos , Trasplante de Riñón/efectos adversos , Pierna/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Diálisis Renal , Sensibilidad y Especificidad , Ultrasonografía DopplerRESUMEN
The amplitude of the N1-P2 component of a response evoked by a 250 Hz test stimulus presented once each 5 sec was measured. Interposed at a rate of one per sec were either 1) a 4000 Hz tone, 2) a 4000 Hz and a 4250 Hz tone presented simultaneously which generated within the ear an audible 250 Hz difference tone, or 3) a 250 Hz tone. The results indicated that the N1-P2 component when preceded by the 4000 Hz plus 4250 Hz stimulus pair was larger than when preceded by a 250 Hz tone, but smaller than when preceded by a 4000 Hz tome. Apparently the processing of the difference tone is unlike that of a sinusoid of the same frequency or that of a high frequency sinusoid which participated in the generation of the difference tone. Parallel electrophysiological data from cochlear recordings are discussed.
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Umbral Auditivo/fisiología , Cóclea/fisiología , Potenciales Evocados , Estimulación Acústica , Percepción Auditiva , Humanos , SonidoRESUMEN
We present a case of the rare coincidence of three mechanisms leading to development of congenital heart disease in intrauterine life: intrinsic defect of the development of the cardiac loop (dextrocardia), failure of normal expansion of the subpulmonary infundibulum (Fallot syndrome) and endocardial cushion defect (common atrium and common atrioventricular valve ). It was associated with partial viscera inversion. A 31-year old man with congenital cyanotic heart disease, and Blalock-Taussig anastomosis was admitted to the hospital due to symptoms of severe cardiac failure. On physical examination: systolic murmur, hepatomegaly, ascites, leg's edema and cyanosis were found. In ECG--atrial fibrillation with 3-d degree a-v block. Standard echocardiography revealed: dextrocardia, a large single atrium with ostia of pulmonary and systemic veins, single atrio-ventricular valve , large ventricular, Fallot-like septal defect. The papillary muscles were not visible in the left ventricle. Aorta and pulmonary trunk arose from morphological right ventricle. The patient died on the 3-rd day of hospitalization in the course of cardiac and respiratory insufficiency. Postmorten examination confirmed the diagnosis.
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Anomalías Múltiples/diagnóstico por imagen , Defectos de la Almohadilla Endocárdica/complicaciones , Tetralogía de Fallot/complicaciones , Adulto , Ecocardiografía , Defectos de la Almohadilla Endocárdica/diagnóstico por imagen , Humanos , Masculino , Tetralogía de Fallot/diagnóstico por imagenRESUMEN
On the basis of own material, the authors discuss the epidemiology, clinical picture, and results of treatment of newborns with polycythaemia. An analysis shows that the blood hyperviscosity syndrome is an underestimated cause of many pathological signs in newborns.
Asunto(s)
Policitemia/terapia , Viscosidad Sanguínea , Humanos , Recién Nacido , Policitemia/sangre , Policitemia/diagnóstico , Resultado del TratamientoRESUMEN
Modern views on the pathological mechanism, clinical symptoms and therapeutic management of neonatal myasthenia gravis are reviewed on the basis of literature reports and own experiences. Particular attention is given to intensive medical care in this condition.
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Acetilcolina/inmunología , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/etiología , Cuidado Intensivo Neonatal , Miastenia Gravis/etiología , Unión Neuromuscular/inmunología , Receptores Colinérgicos/inmunología , Autoanticuerpos/análisis , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Inhibidores de la Colinesterasa/administración & dosificación , Terapia Combinada , Recambio Total de Sangre , Humanos , Recién Nacido , Miastenia Gravis/congénito , Miastenia Gravis/inmunología , Miastenia Gravis/terapia , Unión Neuromuscular/efectos de los fármacos , Receptores Colinérgicos/efectos de los fármacosRESUMEN
CD-1 mice were treated intravenously with streptozotocin, 200 mg/kg, and tested 2 weeks later or treated with 60 mg/kg and tested 3 days later. Both treatments changed the tail flick response of heroin and 6-monoacetylmorphine (6 MAM) given intracerebroventricularly from a mu- to delta-opioid receptor-mediated action as determined by differential effects of opioid receptor antagonists. The response to morphine remained mu. Heroin and 6 MAM responses involved delta1 (inhibited by 7-benzylidenenaltrexone) and delta2 (inhibited by naltriben) receptors, respectively. These delta-agonist actions did not synergize with the mu-agonist action of morphine in the diabetic mice. The expected synergism between the delta agonist, [D-Pen2-D-Pen5]enkephalin (DPDPE), and morphine was not obtained in diabetic mice. Thus, diabetes disrupted the purported mu/delta-coupled response. In nondiabetic CD-1 mice, heroin and 6 MAM produced a different mu-receptor response (not inhibited by naloxonazine) from that of morphine (inhibited by naloxonazine). Also, these mu actions, unlike that of morphine, did not synergize with DPDPE. The unique receptor actions and changes produced by streptozotocin suggest that extrinsic in addition to genetic factors influence the opioid receptor selectivity of heroin and 6 MAM.
Asunto(s)
Analgésicos Opioides/farmacología , Diabetes Mellitus Experimental/fisiopatología , Heroína/farmacología , Receptores Opioides delta/efectos de los fármacos , Receptores Opioides mu/efectos de los fármacos , Animales , Antibacterianos/farmacología , Compuestos de Bencilideno/farmacología , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Encefalina D-Penicilamina (2,5) , Encefalinas/farmacología , Inyecciones Intraventriculares , Masculino , Ratones , Morfina/farmacología , Derivados de la Morfina/farmacología , Naloxona/análogos & derivados , Naloxona/farmacología , Naltrexona/análogos & derivados , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Nociceptores/efectos de los fármacos , Dolor/tratamiento farmacológico , Dolor/fisiopatología , Receptores Opioides delta/agonistas , Estreptozocina/farmacología , Factores de TiempoRESUMEN
43 patients with end-stage renal failure maintained on hemodialysis were studied by echocardiography before and after hemodialysis. Considering possibility, that left ventricule can be enlarged due to intrinsic factors impairing their performance, like myocardial fibres damage in coronary disease or inflammation and extrinsic factors like hypertension, overhydration, anemia, arteriovenous shunt and humoral changes (electrolyte imbalance, uremic toxins, acidosis) three groups of patients were chosen: A--with normal left ventricular diameter, B--with enlarged left ventricule before and after dialysis, C--with enlarged left ventricule only before dialysis. Mean velocity of circumferential fibre shortening (mVcf) and ejection fraction (EF) as left ventricular contractility indexes and end-systolic meridional wall stress as afterload index were determined. Stress-shortening relations before and after hemodialysis were compared in groups, to determine possible intrinsic contractility impairment of the left ventricule. No differences in groups were found in preload reduction (weight loss) and humoral changes (BUN, creatinine, pH, potassium, calcium, hematocrit), also blood pressure was not significantly different in all groups. Hemodialysis improved contractility only in patients with normal left ventricular diameter and significant reduction of afterload. In group A and C stress-shortening relation increased after dialysis. In group B decreased probably because of the lack of mVcf improvement despite reduction of stress in two patients. It is possible that these two patients had impaired contractility and enlarged left ventricle due to intrinsic factors.
Asunto(s)
Fallo Renal Crónico/terapia , Contracción Miocárdica/fisiología , Diálisis Renal , Función Ventricular Izquierda/fisiología , Adolescente , Adulto , Femenino , Humanos , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana EdadRESUMEN
Cervical synovial sarcoma has been reported in only 15 cases; in none of these was there any association with a vascular structure. A patient with cervical synovial sarcoma encompassing the bifurcation of the left carotid artery underwent a left radical neck dissection, including excision of the left external carotid artery and the hypoglossal nerve. The tumor was dissected away from the common carotid and internal carotid arteries. Although the fibrous pseudocapsule of the tumor had not involved the fibrous adventitia of the carotid arteries. Radiation therapy with 6000 rads tumor dose was administered to a wide local field. There is no evidence of recurrence 1 year postoperatively. Histologic and ultrastructural findings were similar to those reported previously in a case of synovial sarcoma of an extremity.