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1.
Rev Esp Med Nucl ; 20(2): 96-101, 2001 Apr.
Artículo en Español | MEDLINE | ID: mdl-11333818

RESUMEN

As a first phase in a nationwide multicenter study to obtain myocardial perfusion normality patterns, this work presents the study design and quality control methodology used to guarantee that the gammacameras fulfilled some minimum quality requirements. The following aspects were considered in the study design in order to guarantee the homogeneity and interchangeability of the results: creation and structure of the work group, data interchange system, data selection and acquisition, centralized archiving and processing, assessment system, study acceptance criteria and distribution of the results. To carry out the instrumental quality control, three phantom studies were established, one to control the rotation center, another to verify tomographic uniformity and a third to simulate the shape and orientation of the left ventricle. The three phantoms circulated through all of the 18 participating centers in this project, which corresponded to 19 gammacameras. Very strict guidelines had to be followed in the acquisition and processing of these phantom studies. If any camera and/or center did not fulfill the criteria established, it was advised of the problem detected in order to correct it. Once the defect was repaired, all the phantoms were sent again for verification. Uniformity of the rotation center was quantified by means of the eccentricity of a 360 degrees orbit, admitting up to a maximum of 10%. Tomographic uniformity was visually assessed, taking in account the number of slices with rings and their contrast and finally no artifacts could be present in the reconstructed study of the ventricle. The center of rotation was within limits in all the cameras except one case while the tomographic uniformity was incorrect in 6 cases. All the departments, except one, corrected the defects detected, and passed the acceptance test. The results made it possible to guarantee adequate homogeneity and instrumental quality in this multicenter study.


Asunto(s)
Circulación Coronaria , Corazón/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Diseño de Equipo , Cámaras gamma , Humanos , Selección de Paciente , Control de Calidad , Valores de Referencia , Proyectos de Investigación , España , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada de Emisión de Fotón Único/normas
2.
Rev Esp Med Nucl ; 20(2): 102-12, 2001 Apr.
Artículo en Español | MEDLINE | ID: mdl-11333819

RESUMEN

This objective of this study was to obtain a pool of Myocardial Perfusion SPECTs with a 99mTetrofosmin stress/rest one day protocol in normal volunteers having a less than or equal to 5% likelihood of coronary artery disease that represents normalcy in the Spanish population. A total of 169 volunteers from 15 hospitals were studied. The volunteers were divided into 5 groups: Groups 1, 2 or 3 corresponding to men < 30 years (n = 33), men between 30 and 50 years (n = 32), or men > 50 years (n = 31); Groups 4 or 5: premenopausal (n = 38) or postmenopausal women (n = 35). A clinical history, physical examination, clinical laboratory parameters, echocardiography and a symptom limited exercise stress test were performed in all of them and had to be normal. The mean likelihood of coronary artery disease was 1.15 +/- 1.07%.Twenty-four segments were analyzed in each study and were classified into 5 grades of uptake (1 = normal, 2, 3, 4 = mild, moderate or severe defect and 5 = no uptake). Defects were then analyzed according to sex and location. Considering the stress and rest studies separately (8,112 segments), only 19 moderate and 75 mild defects were found, these corresponding to 16 volunteers, with more inferior defects in men and anterior defects in women. These data validate the normalcy of our population. A pool of Myocardial Perfusion SPECTs with a 99mTetrofosmin stress/rest one day protocol in normal volunteers that represents Spanish normal values was obtained.


Asunto(s)
Circulación Coronaria , Corazón/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Factores de Edad , Anciano , Femenino , Pruebas de Función Cardíaca , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Selección de Paciente , Posmenopausia , Premenopausia , Valores de Referencia , Factores de Riesgo , Caracteres Sexuales , España
3.
Aviat Space Environ Med ; 69(6): 562-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9641402

RESUMEN

BACKGROUND: Previous studies have shown the diagnostic relevance of the so-called free testosterone/cortisol ratio (FTCR). A condition of overtraining might indeed exist in an athlete when at least one of the two following criteria are observed: a) a FTCR value lower than 0.00035 (FT in nmol x L(-1) and C in micromol x L(-1)); and b) a decrease in the FTCR of 30% or more. On the other hand, no previous research has studied the incidence of overtraining in special military units as a result of their demanding training programs. HYPOTHESIS: A percentage of recruits of the Spanish special military Unit, "Grupo de Operaciones Especiales," (GOES) might be overtrained. It was the purpose of our study to analyze the effects on the FTCR of an intense physical training program performed by recruits of the GOES. METHODS: Before (PRE) and after (POST) an 8-wk training program, respectively, the following measurements were made in 42 recruits of the GOES: hematological and hormonal parameters (FTCR), aerobic and anaerobic tests, and strength and power tests. RESULTS: A high incidence (10 subjects, 23.8% of total) of overtraining existed among conscripts, as determined by the absolute criterium of a decline in the FCTR of 30% or more when comparing PRE and POST values. Additionally, overtraining was associated with a decrease in performance (i.e., isometric strength, vertical jump, Wingate tests). CONCLUSIONS: In addition to some conventional measurements of performance, the FTCR might be used to monitor exercise training in military units, in order to prevent overtraining.


Asunto(s)
Ejercicio Físico/fisiología , Hidrocortisona/sangre , Medicina Militar , Testosterona/sangre , Adulto , Humanos , Masculino , Resistencia Física
4.
Actas Urol Esp ; 20(3): 255-60, 1996 Mar.
Artículo en Español | MEDLINE | ID: mdl-8712042

RESUMEN

This study analyzes the changes in serum and urinary PSA values in 28 subjects; 13 with creatinine clearance under 75 ml/mn and 15 with creatinine clearance over 75 ml/mn. Both groups were compared for prostate size, measured by transrectal ultrasound, prostate weight, serum PSA (SPSA), 24h urine PSA (PSAO), PSA clearance (PSACl), serum creatinine (SCr), creatinine clearance (CrCl), PSA density (PSAD), PSA/creatinine ratio (PSA/Cr) and PSACl/CrCl ratio. Mean values of SPSA and PSAO were 4.5 +/- 0.8 and 222 +/- 29.7 ng/ml respectively, values for SCr, CrCl and PSACl averaging 1.62 +/- 0.2 mgr/dl, 71.6 +/- 6.5 ml/mn and 150.5 +/) 32.9 ml/mn. Median prostate size was 32.6 +/- 3.9 cc, with weights of 40.3 +/- 4.9 g and mean PSA density (PSAD) 0.13 +/- 0.02. The results of the homogeneity study showed that there are no significant differences between both groups with regard to the variables considered in the study. SPSA values were higher in patients with CrCl < 75; 3.4 vs 5.7, but not significantly. There are no significant differences between PSAO and PSACl values for both groups, even though PSAO levels were higher in patients with CrCl < 75 ml/min (p = 0.1). PSAD values for patients with CrCl > 75 ml/mn were lower than those for patients with CrCl < 75 ml/mn; 0.09 vs 0.17 (p = 0.08). In the entire sample, PSAD levels showed correlation with SPSA and PSA/Cr values; R = 0.63 (P = 0.0003) and r = 0.5 (p = 0.009) respectively. Also, they were significantly but inversely correlated with PSACl levels; r = - 0.5 (p = 0.006) and PSACl/CrCl; r = - 0.048 (p = 0.01). No correlation was seen between PSAD values and the following parameters; PSAO (p = 0.7), SCr (p = 0.5) and CrCl (p = 0.27). When the group of patients with CrCl < 75 ml/mn is considered, PSAD values are correlated exclusively with PSACl values; r = - 0.69 (p = 0.008) and PSACl/CrCl; r = 0.68 (p = 0.009). Our data appear to indicate that there is a certain relationship between PSAD and the renal function although the physiopathological mechanism responsible for that is unknown. Nevertheless, considering the sample size, more comprehensive studies will be necessary to obtain more convincing results.


Asunto(s)
Enfermedades Renales/metabolismo , Antígeno Prostático Específico/análisis , Hiperplasia Prostática/metabolismo , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Hiperplasia Prostática/patología
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