ABSTRACT
El umbral anaeróbico ha sido utilizado como un buen indicador de capacidad funcional y de implicancias pronósticas en pacientes cardíacos. El objetivo fue evaluar un método no invasivo como el punto de quiebre del doble producto (PQDP) durante el ejercicio, punto en el cual se produjo un aumento claro y sostenido de la pendiente de doble producto (DP) durante la prueba de esfuerzo incremental. DP= frecuencia cardiaca (FC) x presión arterial sistólica (PAS), que podría ser aplicado para el entrenamiento físico y de información pronóstica en pacientes con enfermedad coronaria (EC). Material y métodos. Se evaluaron 33 hombres y 9 mujeres de 64,8 ± 7,6 años con EC documentada, clínicamente estables con tratamiento médico y en ritmo sinusal. Todos realizaron una PEG en cinta deslizante. El ejercicio consistió en un período inicial de entrada en calor (1 km/h) con cargas crecientes por etapa de 0,4 km/h cada minuto hasta el límite de tolerancia del sujeto. El consumo de oxígeno (VO2) se midió con un sistema portátil (COSMED), la FC con un ECG de 12 derivaciones y la presión arterial por esfigmomanometría en cada etapa. El DP vs VO2 fue sometido a 3 evaluadores independientes para la determinación visual del VT1 y PQDP. El test de Student se utilizó para comparar velocidad (km/h) en VT1 y PQDP y el coeficiente de correlación de Pearson entre ambos parámetros (p<0,05). Resultados. Los pacientes no tuvieron síntomas. Se determinó el VT1 y PQDP en todos ellos. La velocidad del PQDP fue de 2,6 ± 0,5 km/h y la velocidad en VT1 2,6 ± 0, 6 km/h, sin diferencias significativas entre ambos. Encontramos una correlación positiva comparando VT1 vs PQDP (r2=0,6). Conclusiones. Se pudo medir el PQDP en pacientes coronarios con una buena correlación positiva con VT1. Esta variable podría ser eficaz en el pronóstico de esta enfermedad y seguimiento con el entrenamiento físico, pero requerirá más sujetos con diferentes condiciones físicas para ser analizada como un parámetro relevante.
The anaerobic threshold has been used as a good indicator of functional capacity and prognostic implications in cardiac patients. The aim of our study was to evaluate an alternative and non invasive method like the double product break point (DPBP), as the point at which a clear and sustained increase in double product (DP) slope occurred during incremental exercise test. DP= heart rate (HR) x systolic blood pressure (SBP), that could be applied for physical training and prognosis information in patients with coronary heart disease (CHD). Material and methods. We evaluated 33 male and 9 female patients mean age 64.8 ± 7.6 years with documented CHD, clinically stables with medical treatment and sinus rhythm, in conditions to walk in a treadmill using an incremental test until exhaustion. The exercise consisted of an initial period of warm up (1 km/h) followed by the work rate being increased by 0.4 km/h each 1 minute stage to the limit of the subjects tolerance. Oxygen consumption (VO2) was measured with a portable system (COSMED), HR trough a 12 lead ECG (SCHILLER) and blood pressure with sphygmomanometer each stage. Double product vs VO2 for each subject was submitted to 3 blind evaluators for visual determination of the ventilatory threshold (VT1) and DPBP, respectively. A Student t test was used to compare speed (km/h) at VT1 and DPBP and Pearsons product-moment correlation to assess the relationship between both parameters (p<0.05). Results. Patients completed the evaluation without symptoms. We could determine VT1 and DPBP in all of them. Speed at DPBP was 2.6 ± 0.5 km/h and speed at VT1 2.6 ± 0.6 km/h, with no significant difference between both values. We found a positive linearship correlation comparing VT1 vs DPBP (r2=0.6). Conclusions. We could measure the DPBP in coronary patients with strong positive correlation with VT1, and could be used as effective variable in the prognosis of this disease and monitoring physical training, but it will require more subjects with different physical conditions to be analyzed as a relevant parameter.
O limiar anaeróbico tem sido usado como um indicador bom da capacidade pulmonar e das suas implicâncias em pacientes cardíacos. O objetivo da nossa pesquisa foi avaliar um método alternativo e não invasivo como o ponto de quebra do duplo produto (PQDP), expressado como o ponto de inflexão na curva do produto da frequência cardíaca (FC) e da pressão arterial sistólica (PAS) durante o exercício que poderia ser aplicada para o treinamento físico e da informação prognóstica em pacientes com doenças coronárias (DC). Material e métodos. Avaliaram-se 33 homens e 9 mulheres de média idade 64,8 ± 7,6 anos com DC documentada, clinicamente estável com tratamento médico e em ritmo sinusal. Todos eles em condições de caminhar numa esteira e, após sua adaptação, usando uma prova incremental hasta o esgotamento extremo. O exercício consistiu num período inicial de preaquecimento (1 km/h) com cargas crescentes por etapa de 0,4 km/h a cada minuto hasta o limite de tolerância do paciente. O consumo de oxigênio (VO2) foi medido com um sistema portátil (COSMED), a FC com um registro ECG de 12 derivações (SCHILLER) e a pressão arterial por esfigmomanometria em cada etapa. O duplo produto vs VO2 para cada paciente foi submetido a 3 avaliadores independentes para a determinação visual do limiar ventilatório (VT1) e PQDP, respectivamente. Uma prova de t de Student foi usada para comparar velocidade (km/h) em VT1 e PQDP e o coeficiente de correlação de Pearson entre ambos os parâmetros (p<0,05). Resultados. Os pacientes completaram a avaliação sem sintomas. Foi obtido o VT1 e PQDP para todos eles. A velocidade no PQDP foi de 2,6 ± 0,5 km/h e a velocidade em VT1 2,6 ± 0,6 km/h, sem diferenças significativas entre ambos os valores. Foi observada uma correlação positiva comparando VT1 vs PQDP (r2=0,6). Conclusões. Foi medido o PQDP em pacientes coronários com uma boa correlação positiva com VT1 e esta variável poderia ser eficaz no prognóstico de esta doença e no seguimento do treinamento físico, porém se precisara de um número maior de indivíduos com diferentes condições físicas para ser analisada como um parâmetro relevante.
ABSTRACT
Objective To investigate the detection methods of atypical bcr-abl rearrangement with b3a3 fusion transcript,and to describe the characteristics of this fusion gene.Methods Karyotype analysis,FISH and RT-PCR were applied to detect the break point of bcr-abl fusion gene in a patient who was diagnosed as acute lymphoblastic leukemia.Results The karyotype of the patient was expressed as 45,XY,-7,t(9;22)(q34;q1 1).The translocation event in chromosome 9 and 22 could be successfully detected by FISH,and a rare bcr-abl rearrangement with b3a3 fusion transcript was detected by RT-PCR with specific primers.Conclusions The rare e14a3 (b3a3) fusion of bcr-abl gene is present in this patient.Clinical laboratories using commercial kits that do not cover such rare fusions are likely to generate false result,thereby declaring combination of various methods to detect fusion genes is necessary.More studies are needed to explore the function and significance of rare bcr-abl fusion genes.
ABSTRACT
Previously, we have reported that age-predicted heart rate at 50%VO<sub>2</sub>max (HR@50%VO<sub>2</sub>max) is an effective index of adjusting appropriate exercise intensity for health promotion exercise. Thus, the aim of this study is to elucidate the change in HR at double product break point (HR@DPBP) and the validity of HR@50%VO<sub>2</sub>max due to improvement of cardiovascular fitness. Ninety two healthy adults (57 +/- 9 years old), who participated in the health exercise training course, were studied. Participants were instructed how to control the intensity of physical activity for DPBP during their daily life. DPBP was determined with the use of incremental exercise test, and METs at DPBP (METs@DPBP), HR@DPBP, ratings of perceived exertion at DPBP (RPE@DPBP) were measured before and after the course. HR@50%VO<sub>2</sub>max was calculated with the following formula; 138 - age/2 (bpm). METs@DPBP significantly increased (p<0.001) after 10 weeks of the course, whereas HR@DPBP did not change. Interestingly, however, there was a significantly positive correlation (p<0.001) between amount of change in METs@DPBP and that in HR@DPBP (ΔHR@DPBP). Multiple linear regression analysis indicated this correlation was independent from sex, age and amount of change in HR at rest (p<0.001). Before and after the course, proportion of study subjects’ %ΔHRs ((HR@50%VO<sub>2</sub>max - HR@DPBP) / HR@DPBP x 100) within -10% ~ +10% were both 48.9%, and proportion of study subjects’ RPEs@DPBP within 11~13 were 92% and 85%, respectively. In this study, it was identified that significantly positive relation between amount of change in cardiovascular fitness and that of ΔHR@DPBP. This finding was independent from potentially affecting factors. In conclusion, this longitudinal study could suggest that HR@50%VO<sub>2</sub>max and RPE were valuable indexes of determining exercise intensity for health promotion exercise.
ABSTRACT
The purpose of this study was to elucidate the relation between double product break point (DPBP) and pulse wave velocity (PWV).Two hundred three healthy Japanese females were studied (mean age; 53.5 +/- 11.7 years old). The DPBP was measured by continuous incremental exercise test with a bicycle ergometer (ML-3600, Fukuda Electronic Co. Ltd). The work rate at DPBP was converted into metabolic equivalents (METs@DPBP). The brachial-ankle PWV (baPWV) was also measured. In addition, height, weight and mean blood pressure (mBP) were measured and physical activity condition in daily life (PA) was evaluated by questionnaire.The mean METs@DPBP was 5.0 +/- 0.7 METs. The mean baPWV was 1,373 +/- 254 cm/ sec. The relation between METs@DPBP and baPWV was investigated with the use of multiple linear regression models with adjustment for affecting factors of baPWV.In this study, it was identified that there was a significantly inverse relation between METs@DPBP and baPWV (<i>p</i> <0.01). This finding was independent from age, height, weight, mBP and PA. Thus, there was an inverse relation between sub-maximal aerobic capacity and arterial stiffness.
ABSTRACT
In this study, we examined a reliability of age-predicted heart rate (HR) for the 50%VO<sub>2</sub>max which is widely used during a training program for health promotion as compared to HR at the double product break point (DPBP). Two hundred fifty six non-hypertensive subjects (NHT), and 49 hypertensive ones under medication (HT) were studied. HT subjects were divided into two subgroups based on antihypertensive medications, ones with HR non-suppression agents (HT+HRNS) and the other with HR suppression agents (HT+HRS). DPBP was measured with the use of an incremental exercise test, and HR at DPBP (HR@DPBP) was determined. Age-predicted HR for the 50%VO<sub>2</sub>max intensity of exercise was calculated with the following formula; HR=138–age/2. Measurable rate of DPBP and HR@DPBP in NHT, HT+HRNS and HT+HRS were 93.8% and 120±14bpm, 92.7% and 104±12bpm, 78.5% and 94±16bpm, respectively. There were significant differences in HR@DPBP and age-predicted HR in NHT and HT+HRS (<i>p</i><0.01 in both groups). But %ΔHR ((age-predicted HR–HR@DPBP)/HR@DPBP x 100) within -10%∼+10% in NHT, HT+HRNS and HT+HRS were 68%, 58% and 14%, respectively. This might be due to HR at rest with sitting position that was significantly correlated to %ΔHR in all groups (r=-0.604, <i>p</i><0.001 in NHT, r=-0.689, <i>p</i><0.001 in HT+HRNS and r=-0.761, <i>p</i><0.05 in HT+HRS, respectively). And the range of HR at rest with sitting position corresponding to -10%∼+10% of %ΔHR were 70∼95bpm in NHT, 71∼93bpm in HT+HRNS and 83∼102bpm in HT+HRS. In addition, this study indicated that DPBP could be measured even under antihypertensive medication that might affect DPBP measurement.In conclusion, we demonstrated that HR at DPBP and age-predicted HR were similar among 58-68% of NHT and HT+HRNS. And the range of HR at rest with sitting position to ensure reliability of age-predicted HR was elucidated.