Physical Activity and Cerebral Small Vein Integrity in Older Adults.

Identifying promoters of cerebral small vein integrity is important to counter vascular contributions to cognitive impairment and dementia. PURPOSE: In this preliminary investigation, the effects of a randomized 24-month physical activity (PA) intervention on changes in cerebral small vein integrity were compared to those of a health education (HE) control. METHODS: Cerebral small vein integrity was measured in 24 older adults (n = 8, PA; n = 16, HE) using ultra-high field MRI before and at the end of the 24-month intervention. Deep medullary veins were defined as straight or tortuous; percent change in straight length, tortuous length, and tortuosity ratio were computed. Microbleed count and white matter hyperintensities were also rated. RESULTS: Accelerometry-based values of PA increased by 17.2% in the PA group but declined by 28.0% in the HE group. The PA group, but not the HE group, had a significant increase in straight vein length from baseline to 24-month follow-up (P = 0.02 and P = 0.21, respectively); the between-group difference in percent change in straight length was significant (increase: median, 93.6%; interquartile range, 112.9 for PA; median, 28.4%; interquartile range, 90.6 for HE; P = 0.07). Between group differences in other markers were nonsignificant. CONCLUSIONS: Increasing PA in late-life may promote cerebral small vein integrity. This should be confirmed in larger studies.

Multicompartmental analysis of triiodothyronine kinetics in hypothyroid patients treated orally or intravenously with triiodothyronine.

Kinetic studies were performed with i.v. 125I T3 in four athyreotic women on two occasions each, once while they were taking oral T3 (30 micrograms T3 every 12 h) and again while on i.v. T3 replacement (same dosage schedule). The kinetic data were analyzed by a 7-compartment model, representing the plasma volume, the fast and slow peripheral exchange compartments, the iodide pool (as a delay compartment prior to appearance in the urine), the intestine (as a delay compartment before appearance in the feces), and the urine and feces. Modeling was done by the SAAM methodology. All data sets, and also the mean data treated as though they were data from a single subject, were fitted for the two limit solutions in which all metabolism was assumed to be in one or the other of the exchange compartments. The mean data set was also fitted to a solution in which limits were imposed on the excretion parameters and the partition of metabolism between the 2 peripheral exchange compartments was estimated. We found that steady-state parameters for removal of T3 from the circulation (the MCRs and DRs) were increased during the i.v. T3 replacement period compared with the oral replacement period, especially in the fast exchange compartment. Measured serum stable T3 levels (RIA) were lower in the i.v. than in the oral study, both at 8 and at 12 h after the most recent T3 dose. These values corresponded to similar differences in the circulating T3 levels projected from the model, although the T3 values projected from the model were greater than the measured T3 levels for unknown reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

[TSH receptor antibodies as a recurrence index of Graves disease treated with antithyroid drugs]. / Anticuerpos anti-receptor de TSH como índice de recidiva en la enfermedad de Graves tratada con drogas antitiroideas.

TSH receptor antibodies (TRAb) measured by the TBI residual assay (TBIr) were studied in 3 groups of Graves disease patients, as follows: 54 non treated cases (Group 1), 20 cases under methimazol treatment (Group 2) and 23 patients who were euthyroid after one year of methimazol treatment (Group 3), in order to evaluate the usefulness of TBIr as a recurrence index in Graves disease following antithyroid drug treatment. In group 1, TBIr was positive in 77.7% (45/54) of the cases. In group 2: 45% (9/20) had positive values for TBIr, all of which had a recurrence of disease during the year following the suppression of the treatment. In group 3, 69.5% patients (16/23) were TBIr positive. In 75% (12/16) of them the abnormally high values of TBIr predicted the recurrence, while 71.43% (5/7) of the patients, TBIr negatives, continued the remission 12 months later. By comparing the TBIr values before and after treatment in the group 3 patients, different possibilities were observed: a) TBIr persistently elevated: 52.17% (12/23). The 83.3% (10/12) had a recurrence before 6 months following treatment termination. b) TBIr, initially elevated, but later showing 50% decrease or negative values: 26.09% (6/23). Every patient was euthyroid one year after the treatment ended. c) TBIr persistently negative: 13.04% (3/23). Two of them had recurrence of their disease. d) TBIr negative which changed later to positive: 8.70% (2/23). Both presented a recurrence. In accordance with these results, we believe that abnormally high TBIr values before or after treatment is a useful recurrence index.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticuerpos anti-receptor de TSH como indice de recidiva en la enfermedad de graves tratada con drogas antitiroideas / TSH receptor antibodies as a recurrence index of Graves disease treated with antithyroid drugs

Estudiamos anticuerpos anti-receptor de TSH (TRAb), medido por un ensayo radioreceptor en suero total (TBir) en 54 pacientes con enfermedad de Graves sin tratamiento (grupo 1), 20 pacientes bajo tratamiento con metimazol (grupo 2) y 23 pacientes eutiroideos luego de completado un año de tratamiento con metimazol, una vez suspendida la terapia (grupo 3), para evaluar si TBir es útil como índice de recidiva en la enfermedad de Graves luego del tratamiento con drogas antitiroideas. En el grupo 1, TBir fue positivo en el 77,7% (45/54) de los casos. En el grupo 2 el 45% (9/20) tuvo valors positivos de TBir. Todos ellos recidivaron la enfermedad dentro del año posterior a finalizar la terapia. El 55% (11/20) tuvo TBir negativos, de ellos sólo el 18,1% (2/20) presentó recidiva en el mismo lapso de tiempo. Considerando globalmente a los pacientes del grupo 3, el 69,5% (16/23) fue TBir positivo. En el 75% (12/16) de los casos los valores anormales elevados de TBI fueron predictivos de la recidiva, mientras que el 71,43% (5/7) de pacientes con TBir negativos permanecia en remisión 12 meses después. De acuerdo al comportamiento de los valores de TBir antes y después del tratamiento, se establecieron distintos patrones de cambio: a) TBir persistentemente elevados: 52,17% (12/23). El 83,3% (10/112) presentó recidiva dentro de los seis meses de finalizada la terapia. b) TBir inicialmente elevado que se negativizó o se redujo en más del 50%: 26,09% (6/23). Todos los casos permanecían eutiroideos un año después de interrumpida la medicación. c) TBir persistentemente negativos: 13,04% (3/23): Dos presentaron recidiva. d) TBI negativo que cambió a positivo: 8,70% (2/23): Los dos presentaron recidiva. De acuerdo a los resultados obtenidos, consideramos útil como índice de recidiva valores de TBI anormalmente elevados durante o depués del tratamiento. En cambio, valores negativos de TBir después de la terapia, considerados aisladamente, no tienen valor pronóstico, debiendo evaluarse si existió un cambio en los valores iniciales (AU)

Anticuerpos anti-receptor de TSH como indice de recidiva en la enfermedad de graves tratada con drogas antitiroideas / TSH receptor antibodies as a recurrence index of Graves' disease treated with antithyroid drugs

Estudiamos anticuerpos anti-receptor de TSH (TRAb), medido por un ensayo radioreceptor en suero total (TBir) en 54 pacientes con enfermedad de Graves sin tratamiento (grupo 1), 20 pacientes bajo tratamiento con metimazol (grupo 2) y 23 pacientes eutiroideos luego de completado un año de tratamiento con metimazol, una vez suspendida la terapia (grupo 3), para evaluar si TBir es útil como índice de recidiva en la enfermedad de Graves luego del tratamiento con drogas antitiroideas. En el grupo 1, TBir fue positivo en el 77,7% (45/54) de los casos. En el grupo 2 el 45% (9/20) tuvo valors positivos de TBir. Todos ellos recidivaron la enfermedad dentro del año posterior a finalizar la terapia. El 55% (11/20) tuvo TBir negativos, de ellos sólo el 18,1% (2/20) presentó recidiva en el mismo lapso de tiempo. Considerando globalmente a los pacientes del grupo 3, el 69,5% (16/23) fue TBir positivo. En el 75% (12/16) de los casos los valores anormales elevados de TBI fueron predictivos de la recidiva, mientras que el 71,43% (5/7) de pacientes con TBir negativos permanecia en remisión 12 meses después. De acuerdo al comportamiento de los valores de TBir antes y después del tratamiento, se establecieron distintos patrones de cambio: a) TBir persistentemente elevados: 52,17% (12/23). El 83,3% (10/112) presentó recidiva dentro de los seis meses de finalizada la terapia. b) TBir inicialmente elevado que se negativizó o se redujo en más del 50%: 26,09% (6/23). Todos los casos permanecían eutiroideos un año después de interrumpida la medicación. c) TBir persistentemente negativos: 13,04% (3/23): Dos presentaron recidiva. d) TBI negativo que cambió a positivo: 8,70% (2/23): Los dos presentaron recidiva. De acuerdo a los resultados obtenidos, consideramos útil como índice de recidiva valores de TBI anormalmente elevados durante o depués del tratamiento. En cambio, valores negativos de TBir después de la terapia, considerados aisladamente, no tienen valor pronóstico, debiendo evaluarse si existió un cambio en los valores iniciales

Anticuerpos anti-receptor de TSH como índice de recidiva en la enfermedad de Graves tratada con drogas antitiroideas. / [TSH receptor antibodies as a recurrence index of Graves disease treated with antithyroid drugs]

TSH receptor antibodies (TRAb) measured by the TBI residual assay (TBIr) were studied in 3 groups of Graves disease patients, as follows: 54 non treated cases (Group 1), 20 cases under methimazol treatment (Group 2) and 23 patients who were euthyroid after one year of methimazol treatment (Group 3), in order to evaluate the usefulness of TBIr as a recurrence index in Graves disease following antithyroid drug treatment. In group 1, TBIr was positive in 77.7

(45/54) of the cases. In group 2: 45

(9/20) had positive values for TBIr, all of which had a recurrence of disease during the year following the suppression of the treatment. In group 3, 69.5

patients (16/23) were TBIr positive. In 75

(12/16) of them the abnormally high values of TBIr predicted the recurrence, while 71.43

(5/7) of the patients, TBIr negatives, continued the remission 12 months later. By comparing the TBIr values before and after treatment in the group 3 patients, different possibilities were observed: a) TBIr persistently elevated: 52.17

(12/23). The 83.3

(10/12) had a recurrence before 6 months following treatment termination. b) TBIr, initially elevated, but later showing 50

decrease or negative values: 26.09

(6/23). Every patient was euthyroid one year after the treatment ended. c) TBIr persistently negative: 13.04

(3/23). Two of them had recurrence of their disease. d) TBIr negative which changed later to positive: 8.70

(2/23). Both presented a recurrence. In accordance with these results, we believe that abnormally high TBIr values before or after treatment is a useful recurrence index.(ABSTRACT TRUNCATED AT 250 WORDS)