HPLC Analysis of Homocysteine and Related Compounds

Homocysteine (Hcy), a sulfur-containing amino acid, is a representative intermediate metabolite of methionine (Met) to cysteine (Cys) via several intermediates. An elevated level of Hcy in plasma plays an important role in diseases such as neural tube defects and Down syndrome. Homocystinuria is the most common inborn error of sulfur metabolism and is caused by mutations in the metabolic enzymes of Hcy. These errors can be caused by abnormal levels of Met metabolites and classified on the basis of plasma Met levels. Additionally, Hcy and related compounds such as glutathione play an important role in maintaining homeostasis. Therefore, the simultaneous determination of Hcy and/or related compounds is required for appropriate clinical management of several diseases. The sulfur-containing amino acids and their derivatives in biological samples are quantified sensitively using high-performance liquid chromatography methods coupled with various detection methods such as UV/Vis, fluorescence, chemiluminescence, electrochemical, mass spectrometry, and tandem mass spectrometry. In this chapter, we review recent advances in these analytical methods and their applications

Quantitation of Carotenoids in Astaxanthin Supplement with Modified HPLC-UV/Vis Method

ｻﾌﾟﾘﾒﾝﾄ中のｱｽﾀｷｻﾝﾁﾝ(AX)およびｶﾛﾃﾉｲﾄﾞ(α-およびβ-ｶﾛﾃﾝ,α-およびβ-ｸﾘﾌﾟﾄｷｻﾝﾁﾝ)の HPLC-UV/Vis 法による定量について記載した｡AX または他のｶﾛﾃﾉｲﾄﾞはC30ｶﾗﾑ(Combi-RP 5; 50×4.6mm, i.d.)で少なくとも35分以内に分離が達成された｡AX および他のｶﾛﾃﾉｲﾄﾞの定量には異なったｹﾝ化条件が必要であった｡さらに､提案した方法は AX ｻﾌﾟﾘﾒﾝﾄにうまく適用することができた｡AX とβ-ｶﾛﾃﾝの定量値はｻﾌﾟﾘﾒﾝﾄの栄養表示とよく一致した｡A quantitation method for astaxanthin (AX) and other carotenoids (α- and β-carotenes, α- and β-cryptoxanthins) in supplements with HPLC-UV/Vis method was described. The separation of AX or other carotenoids at least within 35 min was achieved using a C30 column (Combi-RP 5; 50×4.6 mm, i.d.). Different saponification conditions for AX and other carotenoids were needed to their quantification. Furthermore, the proposed method could be successfully applied to AX supplements. The quantitation data for AX and β-carotene were well-agreed with on nutrition fact of the supplements

A Single-institution Study on Predictors of Short-term Progression from Mild Cognitive Impairment in Parkinson’s Disease to Parkinson’s Disease with Dementia

Background: Patients with non-demented Parkinson’s disease (PD) sometime have mild cognitive impairment (MCI), and mild cognitive impairment in Parkinson’s disease (PD-MCI) may convert to Parkinson’s disease with dementia (PDD) within several years. Cognitive impairment also occurs in the early stages of the disease, gradually progressing to lower quality of life and instrumental activities of daily living. It is important to elucidate the predictors of progression from PD-MCI to PDD via longitudinal studies. Methods: This was a single center, case-control study. We analysed data from 49 patients with PD-MCI diagnosed as level I using the Movement Disorder Society PD-MCI criteria at baseline who had completed 1.5 years of follow-up. We defined patients who progressed to PDD as patients with progressive PD-MCI and patients who did not progress to PDD as patients with non-progressive PD-MCI. Depression, apathy, sleep disorders, constipation, light-headedness, hallucinations, impulse control disorders (ICDs) and impulsive-compulsive behaviors (ICBs) at baseline were statistically analysed as predictors of progression. Results: Of the 49 PD-MCI patients, 33 did not convert to PDD (non-progressive PD-MCI), and 16 converted to PDD (progressive PD-MCI). The Mini-Mental State Examination (MMSE) score, light-headedness and ICDs were elucidated as predictors of progressive PD-MCI via a multivariate logistic regression model. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each item were MMSE score, OR 0.324, 95% CI 0.119-0.882, P = 0.027; light-headedness, OR 27.665, 95% CI 2.263-338.185, P= 0.009; and ICDs, OR 53.451, 95% CI 2.298-291.085, P = 0.010. Conclusion: Cognitive function, ICDs and light-headedness may be risk factors for the development of PDD in PD-MCI patients

Effects of unconscious thought on lie detection

Unconscious thought, defined as a situation where conscious attention is directed elsewhere rather than on the decision being made, has been reported as an effective way to uncover a target's lie (Reinhard et al., 2013). We reexamined the study of Reinhard et al. in a Japanese setting and also investigated how perceivers' personality traits related to accurate lie detections and true/false response tendency. Moreover, we examined how lie detection affected perceivers' interpersonal relationships. An experiment was conducted with 56 university students. Results indicate that students were more likely to make correct judgements when targets told the truth than when they lied. However, unconscious thought did not increase lie detection rates or true/false response tendency compared with conscious thought and control conditions. Among the personality traits that we used, state anxiety, social skills, and tendency to lie affected the lie detection rate. State anxiety also affected the true/false response tendency. Finally, perceiving a target telling the truth led participants to want to continue relationships, and this process was mediated by the impression of the targets. The cultural differences in unconscious thought, possible reasons our results did not replicate the findings of Reinhard et al., and the importance of state anxiety in lie detection are discussed.本論文は，第一著者が広島大学教育学部に提出した平成26年度卒業論文を基に作成したものである

Prevalence of Dementia and Mild Cognitive Impairment in the Rural Island Town of Ama-cho, Japan

Aims: In order to determine the prevalence of dementia and mild cognitive impairment (MCI), we conducted a population-based study in Japan. Methods: Participants included 924 subjects aged 65 years or older who resided in the town of Ama-cho. In phase 1 of the study, the Mini-Mental State Examination and Clinical Dementia Rating were administered for screening purposes. In phase 2 of the study, the subjects who screened positive were further examined by neurologists. Dementia and MCI were diagnosed by means of DSM-IV and International Working Group on MCI criteria, respectively. Results: By the prevalence date of June 1, 2010, 24 subjects had deceased or lived outside the town. In total, 723 of the remaining 900 subjects received a phase 1 test. In phase 2, 98 subjects were diagnosed with amnestic MCI, 113 subjects with non-amnestic MCI, and 82 subjects with dementia. Of the subjects who did not receive the phase 1 test, 66 subjects were diagnosed as having dementia according to data from their town medical card or the Long-term Care Insurance System. The crude prevalence of amnestic MCI, non-amnestic MCI, and dementia were 10.9, 12.6, and 16.4%, respectively. Conclusion: Consistent with the striking increase in the number of elderly individuals, we report higher prevalence of MCI and dementia in Japan than previously described

Study on the Timing of Degassing for Reproducible Preparation of Polymer-Based Monolithic Columns

The influence of timing of degassing during the preparation procedure on reproducible preparation of polymer-based monolithic columns was investigated. The degassing of each solvent before preparing the polymerization mixture exhibited good reproducibility and was found to be appropriate for the monolithic column without any change in the composition of the polymerization mixture

Enhancement of peroxyoxalate chemiluminescence intensity by surfactants and its application to detect detergent.

Enhancement of peroxyoxalate chemiluminescence (PO-CL) intensity by a surfactant in the H(2)O(2)/bis(2,4,6-trichlorophenyl)oxalate (TCPO)/rhodamine B system was described. The effects of 15 surfactants were evaluated by comparing the ratio of a relative CL intensity (RCI) with surfactant to that of the blank in each system. In preliminary study, H(2)O(2)/imidazole-HNO(3) buffer/TCPO/rhodamine B system was used to study the effects of surfactants on PO-CL intensity. Fourteen surfactants reduced the CL intensity at the 2% concentration, where their relative CL intensities ranged from 0.6 to 93.5%. Some of these phenomena may be caused by a notable change of pH that was occurred by adding the surfactant. Additionally, enhancement of PO-CL intensity was studied by using system (1) H(2)O(2)/TCPO/rhodamine B and (2) H(2)O(2)/imidazole-HNO(3) buffer/TCPO/systems. In the system 1, the favorable enhancement of CL intensity (ranged from 124 to 472%) was observed with 9 surfactants at the 0.5% concentration. This result suggested that several surfactants might play a role as a catalyst in the PO-CL reaction. There was no tendency to enhance CL intensity among the surfactant types. In the system 2, the enhancement of CL intensity was also observed by adding with 11 surfactants, which might be mainly caused by the fluorescent impurities of surfactants used. Furthermore, detection of detergent commercially available was applied by using the system 1

4-Carbomethoxybenzaldehyde as a highly sensitive pre-column fluorescence derivatization reagent for 9,10-phenanthrenequinone.

9,10-Phenanthrenequinone (PQ) is harmful environmental pollutant that is detected in airborne particulates. The measurement of PQ in the air should be necessary to evaluate the potential adverse effects of PQ on human health. We have recently developed a determination method for PQ based on the fluorescence derivatization of PQ using benzaldehyde and ammonium acetate as a reagent. In this study, in order to obtain more sensitive and selective fluorescence derivatization reaction, we measured the fluorescence of the reaction mixture of PQ with 21 kinds of aromatic aldehydes in the presence of ammonium acetate. Among the tested aldehydes, 4-carbomethoxybenzaldehyde was found to be the best reagent in regard to fluorescence intensity and emission wavelength maximum. Based on the fluorescence derivatization with 4-carbomethoxybenzaldehyde, a highly sensitive chromatographic method was developed for the determination of PQ with the detection limit (S/N=3) of 1.2 fmol/injection

Disconnectivity between Dorsal Raphe Nucleus and Posterior Cingulate Cortex in Later Life Depression

The dorsal raphe nucleus (DRN) has been repeatedly implicated as having a significant relationship with depression, along with its serotoninergic innervation. However, functional connectivity of the DRN in depression is not well understood. The current study aimed to isolate functional connectivity of the DRN distinct in later life depression (LLD) compared to a healthy age-matched population. Resting state functional magnetic resonance imaging (rsfMRI) data from 95 participants (33 LLD and 62 healthy) were collected to examine functional connectivity from the DRN to the whole brain in voxel-wise fashion. The posterior cingulate cortex (PCC) bilaterally showed significantly smaller connectivity in the LLD group than the control group. The DRN to PCC connectivity did not show any association with the depressive status. The findings implicate that the LLD involves disruption of serotoninergic input to the PCC, which has been suggested to be a part of the reduced default mode network in depression

Trends of Analytical Research on Drug-drug Interaction

薬物-薬物相互作用は薬物治療において非常に重要な事項である｡薬物はそれ自身で副作用を生じうるが､複数の薬物を併用することで予期しない重篤な有害事象を引き起こすこともある｡この意味で､薬物-薬物相互作用に関する分析化学的な研究が非常に重要であり､薬物治療の手助けとなる｡本総説では､薬物-薬物相互作用の分析化学的研究の最近の動向について､特に微小透析技術に基づいた方法について記述する｡Drug-drug interaction is very important matter for the medicinal treatment of diseases. Drugs can cause serious side effects by themselves, beside concomitant use of plural drugs sometimes causes unexpected serious adverse events. In this sense, the analytical research for the drug-drug interaction is very important and helpful for medicinal treatment. In this review, the recent trends of analytical research on drug-drug interaction, especially methods based on a microdialysis technique, were described