Isolation of Acein-2, a novel angiotensin-I-converting enzyme inhibitory peptide derived from a tryptic hydrolysate of human plasma

AbstractWe previously described a novel angiotensin-I-converting enzyme (ACE) inhibitory peptide, designated Acein-1, that was isolated from a tryptic hydrolysate of human plasma. We now report a second such inhibitory peptide, Acein-2 obtained from the same hydrolysate. The peptide was purified by gel filtration and cation exchange chromatography followed by reversed-phase gradient and isocratic high performance liquid chromatography. Acein-2 was found to be a tripeptide, Leu-Ile-Tyr, which is thought to correspond to f(518–520) of human α2-macroglobulin. The synthetic tripeptide showed a potent dose-dependent inhibition of ACE, with an IC50 value of 0.82 μmol/l. Lineweaver–Burk plots suggested that Acein-2 as well as the previously described Acein-1 are non-competitive inhibitors

近赤外線スペクトロスコピィを用いた覚醒剤精神病と統合失調症の鑑別

Despite some slight differences in symptomatology, differential diagnosis of methamphetamine-induced psychosis (MAP) versus schizophrenia can be challenging because both disorders present a large overlap in their clinical symptoms. However, a recent study has shown that near-infrared spectroscopy (NIRS) performed during a cognitive task can be a powerful tool to differentiate between these two disorders. Here, we evaluated verbal fluency task performance during NIRS in 15 patients diagnosed with MAP and 19 with schizophrenia matched for age and sex. We used prefrontal probes and a 24-channel NIRS machine to measure the relative concentrations of oxyhaemoglobin every 0.1 s during the task. For each patient, the neurocognitive function and clinical psychopathology were evaluated using the Positive and Negative Symptom Scale (PANSS), and the Brief Assessment of Cognition in Schizophrenia (BACS). Oxyhaemoglobin changes in the prefrontal cortex were significantly higher in the MAP group compared to those in the schizophrenia group, particularly in the right dorsolateral prefrontal cortex. In contrast, we found no significant difference in PANSS and BACS scores. Our findings suggest that NIRS measurement could be applied to differentiate patients with MAP from those with schizophrenia, even in cases where clinical symptoms are similar.博士（医学）・甲第645号・平成28年3月15日This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0

Gray and White Matter Changes in Subjective Cognitive Impairment, Amnestic Mild Cognitive Impairment and Alzheimer's Disease: A Voxel-Based Analysis Study

<div><p>Subjective cognitive impairment may be a very early at-risk period of the continuum of dementia. However, it is difficult to discriminate at-risk states from normal aging. Thus, detection of the early pathological changes in the subjective cognitive impairment period is needed. To elucidate these changes, we employed diffusion tensor imaging and volumetry analysis, and compared subjective cognitive impairment with normal, mild cognitive impairment and Alzheimer's disease. The subjects in this study were 39 Alzheimer's disease, 43 mild cognitive impairment, 28 subjective cognitive impairment and 41 normal controls. There were no statistically significant differences between the normal control and subjective cognitive impairment groups in all measures. Alzheimer's disease and mild cognitive impairment had the same extent of brain atrophy and diffusion changes. These results are consistent with the hypothetical model of the dynamic biomarkers of Alzheimer's disease.</p></div

Differences in fractional anisotropy among normal controls, subjective cognitive impairment, mild cognitive impairment and Alzheimer's disease.

<p>NC indicates normal control; SCI, subjective cognitive impairment; MCI, mild cognitive impairment; AD, Alzheimer's disease. The statistical brain maps show colored voxels (green to light green) in regions of significantly lower fractional anisotropy (FA) (p<0.001). The blank brain maps (NC > SCI, MCI > AD) show that there are no significant differences between those subject groups (NC > SCI, MCI > AD).</p

Group differences in mean diffusivity.

<p>The statistical brain maps show colored voxels (dark blue to light blue) in regions of significantly higher mean diffusivity (MD) (p<0.001). The blank brain map (NC < SCI) shows that there are no significant differences between NC and SCI groups.</p

Gray matter atrophy across subjects groups.

<p>Voxel-based analysis showing regions of gray matter atrophy across groups. Clusters are overlaid on the MNI standard brain. Red- to yellow-colored voxels show regions with significance in the analyses. The blank brain map (NC > SCI) shows that there are no significant differences between NC and SCI groups.</p

Demographic and diagnostic data of the participants.

<p>NC, normal controls; SCI, subjective cognitive impairment; MCI, mild cognitive impairment; AD, Alzheimer's disease; GDS, Global Deterioration Scale; MMSE, Mini Mental State Examination; ADAS-Cog., Alzheimer's disease assessment scale - cognitive subscale; WMS-R, Wechsler memory scale - revised; N.S., not significant; DWMH, deep white matter hyperintensity; ChEI, cholinesterase inhibitor.</p><p>*χ² test, **GDS; stage 4, n = 25, stage 5, n = 14, ***one way analysis of variance, ****lack of one subject's data.</p