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Soichiro Mochio

Publications and source records attributed to Soichiro Mochio.

5 recordsLinked to original sources
PubMed2005

Cardiovascular dysautonomia in de novo Parkinson's disease.

BACKGROUND: Clinical symptoms of Parkinson's disease (PD) include not only motor distress, but also autonomic dysfunction. OBJECTIVE: To clarify the progression of autonomic nervous dysfunction in PD. METHODS: The subjects were 44 patients with de novo PD. Autonomic nervous function, including cardiac sympathetic gain, was evaluated on the basis of cardiac radioiodinated metaiodobenzylguanidine (MIBG) uptake, the response to the Valsalva maneuver, and spectral analyses of the RR interval and blood pressure. RESULTS: Decreased cardiac MIBG uptake was found even in patients with early stage PD. MIBG uptake gradually decreased with increased disease severity. Hemodynamic studies using the Valsalva maneuver revealed that patients with early stage PD had reduced baroreceptor reflex sensitivity (BRS) in phase II, but not phase IV. Blood pressures normally rose in phases II and IV, but the increments decreased with disease progression. In early stage PD, the low frequency power of the RR interval (RR-LF) and the ratio (LF/HF) of RR-LF to the high frequency component of the RR interval (RR-HF) were significantly lower than the respective control values, despite no significant difference in RR-HF; these variables decreased with disease progression. CONCLUSION: Our results show that latent sympathetic nervous dysfunction without parasympathetic dysfunction, especially that involving the sinus node, is already present in early stage de novo PD. It is unclear whether the responsible lesion is central or peripheral.

3-Iodobenzylguanidine↗
PubMed2004

Effects of 1-Hz repetitive transcranial magnetic stimulation on acute pain induced by capsaicin.

The aim of this study is to investigate the efficacy of 1-Hz repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) on acute pain induced by intradermal capsaicin injection and to elucidate its mechanisms by single-photon emission computed tomography (SPECT). We compared time courses of a subjective scale of pain induced by intradermal capsaicin injection in seven normal subjects under three different conditions: rTMS over M1, sham stimulation, and control condition (natural course of acute pain without any stimulation). In ten normal subjects, using SPECT, we also studied differences in regional cerebral blood flow (rCBF) after capsaicin injection between two conditions: rTMS over M1 and the control condition. rTMS over M1 induced earlier recovery from acute pain compared with the sham or control conditions. Under rTMS over the right M1 condition compared with the control condition, the SPECT study demonstrated a significant relative rCBF decrease in the right medial prefrontal cortex (MPFC) corresponding to Brodmann area (BA) 9, and a significant increase in the caudal part of the right anterior cingulate cortex (ACC) corresponding to BA24 and the left premotor area (BA6). A region-of-interest analysis showed significant correlation between pain reduction and rCBF changes in both BA9 and BA24. We conclude that rTMS over M1 should have beneficial effects on acute pain, and its effects must be caused by functional changes of MPFC and caudal ACC.

Adult↗
PubMed2003

Evaluation of baroreflex sensitivity by the sequence method using blood pressure oscillations and R-R interval changes during deep respiration.

BACKGROUND: Baroreflex sensitivity assessments have been considered to be important to evaluate cardiac autonomic neuropathy. The phenylephrine method, Valsalva maneuver or sequence method at rest caused several problems. We evaluated the usefulness of the sequence method during deep respiration. METHOD: Baroreflex sensitivity was evaluated in 20 normal volunteers and 50 patients with Parkinson's disease. R-R intervals and systolic blood pressures were obtained by electrocardiogram and tonometry using a continuous blood pressure monitoring system. The sequence method is an evaluation of baroreflex sensitivity using sequences of 3 or more consecutive beats for 4 min. Baroreflex sensitivity was also assessed by the Valsalva maneuver at 5 beats before the peak systolic blood pressure of phase IV. The slope of the linear interrelationship between systolic blood pressure and the following R-R interval, i.e. baroreflex sensitivity (ms/mm Hg), was calculated with a correlation coefficient greater than 0.8. RESULT: The mean value of baroreflex sensitivity obtained by the Valsalva maneuver was 7.91 in normal volunteers and 5.35 in patients with Parkinson's disease; the one obtained by the sequence method at rest was 9.10 in normal volunteers and 8.42 in patients with Parkinson's disease, and the one obtained by the sequence method during deep respiration was 10.23 in normal volunteers and 6.73 in patients with Parkinson's disease. In some cases with Parkinson's disease, baroreflex sensitivities could not be found, whereas in all patients with Parkinson's disease, the sequence method during deep respiration could be used for evaluations. Significant correlations were found among the baroreflex sensitivities obtained by the Valsalva maneuver, and the sequence method at rest or during deep respiration in normal volunteers and patients with Parkinson's disease. CONCLUSIONS: The baroreflex sensitivity obtained by the sequence method during deep respiration could be investigated noninvasively in all cases with PD, being thus a useful method for clinical evaluation of baroreflex sensitivity.

Aged↗
PubMed2003

[Cardiac sympathetic dysfunction in Parkinson's disease--relationship between results of 123I-MIBG scintigraphy and autonomic nervous function evaluated by the Valsalva maneuver].

We examined whether the results of 123I-MIBG scintigraphy reflect cardiac sympathetic nerve function in patients with Parkinson's disease (PD). The subjects were 62 patients with Parkinson's disease (age, 65.4 +/- 6.3 years) and 53 controls (65.2 +/- 7.1 years). All subjects underwent 123I-MIBG scintigraphy and QTc interval measurement on ECG. Hemodynamic autonomic function was estimated by the Valsalva maneuver in 37 subjects (63.9 +/- 5.2 years) randomly selected from the patients with PD. As control, the Valsalva maneuver was also done in 20 randomly selected controls (64.1 +/- 5.0 years), and 123I-MIBG scintigraphy was performed in 21 controls (67.7 +/- 5.3 years old). The subjects rested in a supine position for 20 min and were given an intravenous injection of 111 MBq 123I-MIBG. Relative organ uptake was determined by the region of interest (ROI) in the anterior view and the ratio of average pixel count in the heart (H) to that in the mediastinum (M) was calculated (H/M ratio) for early (after 15 min) and delayed (after 3 hrs) periods. The Valsalva maneuver was done by having the subjects exhale into a mouthpiece at an expiratory pressure of 40 mmHg for 15 seconds. Blood pressure and RR intervals were measured during the Valsalva maneuver by tonometry, using a noninvasive blood pressure monitoring system (ANS 508, Nihon Colin Co., Ltd.). Baroreceptor reflex sensitivities (BRS) of the second phase (BRS II) and fourth phase (BRS IV) of the Valsalva maneuver were calculated, and blood pressure elevations during the late second phase (IIp) and fourth phase (IVp) were measured. QTc was greater in the patients with PD (417 ms) than in the control subjects (409 ms). The H/M ratios of the early and delayed images in the patients with PD (1.76, 1.61) were significantly lower than those in the control subjects (2.56, 2.45). The early and delayed H/M ratios significantly correlated with the severity of disease according to Hoehn-Yahr stage. QTc interval and IVp significantly correlated with early and delayed H/M ratios. No other significant correlations were detected. The early H/M ratio in the patients with PD who had IVp within the normal range was lower than the early H/M ratio in control subjects. Our results show that early and delayed H/M ratio correlates with cardiac autonomic function, evaluated on the basis of QTc interval and the Valsalva maneuver, but not with baroreceptor reflex sensitivity or vasomotor autonomic function. Our findings suggest that silent cardiac autonomic dysfunction may be evaluated by 123I-MIBG scintigraphy, because early and delayed H/M ratios were lower in the patients with PD who had normal IVp than in the control subjects.

3-Iodobenzylguanidine↗