Pico Device Co.

Chikusa, Japan

Pico Device Co.

Chikusa, Japan
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Hirayama M.,Nagoya University | Tsunoda M.,University of Tokyo | Yamamoto M.,Takamatsu Neurology Clinic | Tsuda T.,Pico device Co. | Ohno K.,Nagoya University
Journal of Parkinson's Disease | Year: 2016

Background: Noninvasive biomarkers for Parkinson's disease (PD) are currently unavailable. Objective: To search for a biomarker unique to PD in sweat and serum. Methods: Sweat samples in 42 PD patients and 16 controls were analyzed using liquid chromatography/mass spectrometry (LC/MS). The principal component analysis (PCA) and the orthogonal projections to latent structures (OPLS) analysis were employed. Serum Phe and Tyr levels were determined using the HPLC-fluorescence detection system in 28 de novo PD patients, 52 L-Dopa-treated PD patients, and 27 controls. Results: PCA and OPLS analyses of LC/MS of sweat samples revealed that Tyr, Phe, Leu (Ile), and Asp have high effect sizes to differentiate PD and controls. As Phe and Tyr are precursors of dopamine, we quantified the serum Phe and Tyr levels in de novo and treated PD patients, as well as in controls. Phe was high in de novo patients, but not in treated patients. In contrast, Tyr tended to be low in treated patients, but not in de novo patients. Tyr/Phe ratios were lower in both de novo and treated patients than in controls. The Tyr/Phe ratios were all higher than 0.82 in controls, whereas 49% of the de novo and treated patients had Tyr/Phe ratios less than 0.82. The low Tyr/Phe ratios were associated with male patients and low doses of entacapone. However, Tyr/Phe ratios were not different between male and female patients, and between patients with and without entacapone. Conclusions: The low serum Tyr/Phe ratio differentiates PD from controls with sensitivity = 0.49, specificity = 1.00, positive predictive value = 1.00, and negative predictive value = 0.40. © 2016 - IOS Press and the authors. All rights reserved.

Yamai K.,Nagoya Institute of Technology | Funada T.,Nagoya Institute of Technology | Ohkuwa T.,Nagoya Institute of Technology | Itoh H.,Nagoya Institute of Technology | Tsuda T.,Pico Device Co.
Analytical Sciences | Year: 2012

This study investigated the effects of diabetic rats induced by streptozotocin (STZ) on acetone concentration emanating from the tail of a rat. Experiments were carried out with male Wistar rats (9 weeks of age, 220 - 250 g body weight). Glucose concentration in the blood was 10.8 ± 0.7 mmol/l for the control group and 39.6 ± 2.4 mmol/l for the diabetic group. β-Hydroxybutyrate concentration in blood was 218 ± 52 μmol/l for the control group and 1439 ± 101 μmol/l for the diabetic group. Both glucose and β-hydroxybutyrate concentrations in the blood of the diabetic group were significantly higher than those of the control group (p < 0.001). Skin gas acetone concentration emanated from rat tail was 124 ± 46 ppb for control and 1134 ± 417 ppb for diabetic. Skin gas acetone concentration emitted from the tail of a rat with diabetes was significantly higher than that from a rat in the control group (p < 0.001). The result indicates that skin acetone emanating from a rat tail is a useful parameter to use for insulin-dependent diabetes (type I). © 2012 The Japan Society for Analytical Chemistry.

Nunome Y.,Nagoya University | Tsuda T.,Pico Device Co. | Kitagawa K.,EcoTopia Science Institute
Analytical Sciences | Year: 2010

Fatty acids (FAs) are biological molecules that are used as major metabolic fuels, and are concerned in important metabolic processes. We have performed a non-invasive and technically rapid and simple method for collecting sweat from humans, followed by GC/MS determination. The sweat was collected from each volunteer (the middle finger) by spraying 70% ethanol aqueous solution (no harmful solvent) into a 1.5-cm3 plastic vial. Analysis of FAs in sweat showed that the sweat solution contains lauric acid (C12:0), myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1), and stearic acid (C18:0). Here, it is demonstrated that FA concentrations for 4 young subjects correlated positively with percent of body fat (r = 0.78) and that the total FA levels for them increased progressively with increasing fasting time when a subject fasted throughout the experiment. 2010 © The Japan Society for Analytical Chemistry.

Tsunoda M.,University of Tokyo | Hirayama M.,Nagoya University | Tsuda T.,Pico device Co. | Ohno K.,Nagoya University
Clinica Chimica Acta | Year: 2015

Background: l-dopa (l-3,4-dihydroxyphenylalanine) is commonly used for treating Parkinson's disease (PD). However, regardless of its prominent effect, therapeutic range of l-dopa narrows down with disease progression, which leads to development of motor complications including wearing off and dyskinesias. In addition, intestinal absorption of l-dopa is inversely correlated with the amount of oral protein intake, and shows intra- and inter-day variability. Hence, frequent monitoring of plasma l-dopa concentrations is beneficial, but frequent venipuncture imposes physical and psychological burdens on patients with PD. Methods: We investigated the usefulness of sweat samples instead of plasma samples for monitoring l-dopa concentrations. With a monolithic silica disk-packed spin column and the high-performance liquid chromatography-electrochemical detection system, l-dopa in sweat samples was successfully quantified and analyzed in 23 PD patients. Results: We found that the Pearson's correlation coefficient of the plasma and sweat l-dopa concentrations was 0.678. Although the disease durations and severities were not correlated with the deviation of the actual sweat l-dopa concentrations from the fitted line, acquisition of the sweat samples under a stable condition was technically difficult in severely affected patients. The deviations may also be partly accounted for by skin permeability of l-dopa. Conclusions: Measuring l-dopa concentrations in sweat is suitable to get further insights into the l-dopa metabolism. © 2015 Elsevier B.V.

Tsunoda M.,University of Tokyo | Hirayama M.,Nagoya University | Ohno K.,Nagoya University | Tsuda T.,Pico device. Co.
Analytical Methods | Year: 2013

l-DOPA (l-3,4-dihydroxyphenylalanine) is commonly used in the treatment of Parkinson's disease. Monitoring the concentration of l-DOPA in human plasma will enable dose optimization, but is rarely performed because current quantification methods are tedious and time-consuming. In this study, a simple method for the determination of l-DOPA in the plasma of patients with Parkinson's disease was developed. A monolithic silica disk-packed spin column with a phenylboronate moiety, which forms stable anionic complexes with the cis-hydroxyl groups of l-DOPA, was used to extract l-DOPA from plasma with extraction recoveries exceeding 90%. The extracted l-DOPA was then separated on a reversed-phase column and detected electrochemically with a boron-doped diamond electrode. The method, which has a limit of detection of 10 fmol, was then successfully applied for the determination of l-DOPA in the plasma of healthy volunteers and patients with Parkinson's disease. © 2013 The Royal Society of Chemistry.

Nakanishi R.,Nagoya Institute of Technology | Ohwaki J.,Nagoya Institute of Technology | Emoto S.,Nagoya Institute of Technology | Mori T.,Nagoya Institute of Technology | And 4 more authors.
Redox Report | Year: 2013

This study was undertaken to investigate the effects of oral L-arginine administration and exercising training on the NO concentration emanating from rat tail and NOx in plasma. Obese (fa/fa) Zucker rats (n = 22) were divided into four groups: (1) oral L-arginine administration (A) (n = 6), (2) exercise training (E), (3) exercise training + L-arginine administration (E + A) (n = 5), and (4) non-exercise training + non-L-arginine administration (N) (n = 6). The control (+/+) Zucker rats (n = 22) were also divided into the same four groups. The body weight of the E + A and the A groups was significantly lower than that of the N group. The NO concentration emitted from the tail was higher in the L-arginine (E + A and A) groups than in the non-L-arginine (E and N) groups in both obese and control rats. Exercise training did not affect the skin gas NO concentration in either obese or control rats. Plasma NOx concentrations in four obese rats were significantly higher than those observed in control rats. Exercise training did not influence the level of plasma NOx in obese or control rats. In conclusion, this study confirmed that L-arginine administration increases the skin gas NO concentration and obesity increases the plasma NOx level. The plasma NOx concentrations were not affected by L-arginine administration or exercise training in obese or control rats. © W. S. Maney & Son Ltd 2013.

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