Biomedical subjects

Mingyuan Zhang

Publications and source records attributed to Mingyuan Zhang.

10 recordsLinked to original sources

PubMed2006

Successful aging in Shanghai, China: definition, distribution and related factors.

OBJECTIVE: There are few studies of successful aging in China. This study was designed to investigate the distribution, and related factors, of successful aging in an elderly Chinese population. METHODS: A cross-sectional, community-dwelling elderly population was surveyed in Shanghai, China. We defined successful aging based on a multi-dimensional model. Correlates of successful aging were explored through the Shanghai Successful Aging Project Questionnaire, which includes sociodemographic questions, and a battery of standardized instruments, including the Chinese version of the Mini-mental State Examination, activities of daily living, and the Life Satisfaction Index A (LSIA). RESULTS: The rate of successful aging was 46.2% [95% confidence interval (CI) 43.6-48.7] among people aged 65 or above, and the rate for males was higher than that for females. The rate was much lower for those aged 85 years or over (9.4%). Logistic regression analysis suggested that female gender and older age were unfavorable factors for successful aging. A higher score on the LSIA, more leisure activities and being currently married related to successful aging. CONCLUSION: The rate of successful aging in Shanghai, China is similar to that found in studies from western countries. There are some potentially modifiable factors that may relate to successful aging.

Activities of Daily Living↗

PubMed2006

[Liquid flow field measurement in a tube with a combination of stenosis and bifurcation].

Two-D liquid velocity field in a tube with a combination of a stenosis and a bifurcation was measured with refractive index matching technique using Laser Doppler Velocimeter (LDV). The flow ratio of main tube to bypass was 1:4. It is found that the axial velocity profile has two peaks in the XOY plane which is skewed to the main tube wall facing the flow from the bypass, and it manifests itself in the form of "M" in the XOZ plane. A two counter-rotating vortices in the main tube cross section downstream the conjunction region is also detected.

Laser-Doppler Flowmetry↗

PubMed2004

Prevalence, severity, and unmet need for treatment of mental disorders in the World Health Organization World Mental Health Surveys.

CONTEXT: Little is known about the extent or severity of untreated mental disorders, especially in less-developed countries. OBJECTIVE: To estimate prevalence, severity, and treatment of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) mental disorders in 14 countries (6 less developed, 8 developed) in the World Health Organization (WHO) World Mental Health (WMH) Survey Initiative. DESIGN, SETTING, AND PARTICIPANTS: Face-to-face household surveys of 60 463 community adults conducted from 2001-2003 in 14 countries in the Americas, Europe, the Middle East, Africa, and Asia. MAIN OUTCOME MEASURES: The DSM-IV disorders, severity, and treatment were assessed with the WMH version of the WHO Composite International Diagnostic Interview (WMH-CIDI), a fully structured, lay-administered psychiatric diagnostic interview. RESULTS: The prevalence of having any WMH-CIDI/DSM-IV disorder in the prior year varied widely, from 4.3% in Shanghai to 26.4% in the United States, with an interquartile range (IQR) of 9.1%-16.9%. Between 33.1% (Colombia) and 80.9% (Nigeria) of 12-month cases were mild (IQR, 40.2%-53.3%). Serious disorders were associated with substantial role disability. Although disorder severity was correlated with probability of treatment in almost all countries, 35.5% to 50.3% of serious cases in developed countries and 76.3% to 85.4% in less-developed countries received no treatment in the 12 months before the interview. Due to the high prevalence of mild and subthreshold cases, the number of those who received treatment far exceeds the number of untreated serious cases in every country. CONCLUSIONS: Reallocation of treatment resources could substantially decrease the problem of unmet need for treatment of mental disorders among serious cases. Structural barriers exist to this reallocation. Careful consideration needs to be given to the value of treating some mild cases, especially those at risk for progressing to more serious disorders.

Adult↗

PubMed2003

Enhanced production of amyloid precursor protein mRNA by peripheral mononuclear blood cell in Alzheimer's disease.

Previous studies have suggested the involvement of amyloid precursor protein (APP) in Alzheimer's disease (AD), as exons 16 and 17 of the APP gene mutations have been found in some familial AD patients. Furthermore, overexpression and deposition of the beta amyloid peptide, a proteolytic product of APP, have been considered as a pathological hallmark of Alzheimer's disease. Therefore, it is of particular interest to determine the expression of APP gene at the transcription level for better understanding of the roles of APP gene in AD pathogenesis. In this work, we employed the quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to quantify APP mRNA transcripts in the peripheral mononuclear blood cells (PMBC) of 52 Alzheimer's patients, 28 vascular dementia (VD) patients, and 60 healthy elderly controls. The results showed that the amount (mean +/- SEM) of APP transcripts per microgram of total cDNA was 4.05 +/- 0.27, 2.73 +/- 0.33, and 2.59 +/- 0.27 amole in AD, VD, and healthy controls, respectively. There was a significant increase (P < 0.05) in the expression of APP mRNA transcripts in AD compared with that in VD or in healthy controls. Thus, our data indicated that variation of APP gene expression in PMBC might be a pathogenic source of Alzheimer's disease.

Aged↗

PubMed2003

Brain glucose metabolism and neuropsychological test in patients with mild cognitive impairment.

OBJECTIVE: To investigate the features of regional cerebral metabolic rate of glucose (rCMRglc) in patients with mild cognitive impairment (MCI) by positron emission-tomography and its relationship with neuropsychological test. METHODS: Positron emission tomography, mini-mental state examination and Wechsler memory scale were applied in 10 patients with MCI and 10 healthy volunteers as the control group. RESULTS: Scores of mini-mental state examination and Wechsler memory scale in MCI patients were lower than those in the control group (P < 0.01). rCMRglc of the left orbital gyrus, right middle temporal gyrus and right putamen was lower in the MCI group than in the control group (P < 0.05). Correlation analysis in the MCI group indicated that rCMRglc of many brain regions such as the orbital gyrus, putamen, left hippocampus and parahippocampal gyrus, cingulate gyrus, left amygdaloid body, precentral gyrus, postcentral gyrus, and medial occipitotemporal gyrus in MCI patients, were correlated negatively with age; while the rCMRglc of many parts of the brain such as the left putamen, temporal lobe, anterior cingulate gyrus, left insular lobe, amygdaloid body, precentral gyrus, postcentral gyrus and medial occipitotemporal gyrus were correlated positively with mini-mental state examination; and rCMRglc of the left putamen, temporal lobe, left insular lobe, precentral gyrus and postcentral gyrus were correlated positively with Wechsler memory scale. The right putamen, the right inferior temporal gyrus, precentral gyrus, and left postcentral gyrus were correlated positively with the length of education. However, only rCMRglc of the left amygdaloid body were correlated positively with gender. CONCLUSION: The rCMRglc was lower in the orbital gyrus and putamen of MCI patients. Their rCMRglc were correlated with their cognitive impairment severity, age, length of education and sex.

Aged↗

PubMed2002

[Psychiatry].

Explore the source record for details and available documents.

Biomedical Research↗

PubMed2002

[The comparison of the regional cerebral metabolism rate of glucose in Alzheimer's disease with mild cognitive impairment].

OBJECTIVE: To study the feature of regional cerebral metabolism rate of glucose (rCMRglc) of Alzheimer's disease (AD) and mild cognitive impairment (MCI) by positron emission tomography (PET) and the relationship between MCI and AD. METHODS: 13 AD patients, 10 MCI patients and 10 health volunteers as a control group (HC) were underwent 18F-fluoro deoxyglucose (18F-FDG)-PET scanning. RESULTS: (1) There was lightly decreasing of radioactivity of temporal lobe and parietal lobe in HC group, a little severer decrease in MCI group, markedly decrease of radioactivity of temporal lobe, parietal lobe and frontal lobe in AD group examined by naked-eye. (2) The rCMRglc of many parts of brain such as frontal lobe, including superior, middle and inferior frontal gyrus, orbital gyrus and rectus gyrus, temporal lobe, including superior, middle and inferior temporal gyrus, parietal lobe, including superior parietal lobe, supramarginal gyrus and angular gyrus, limbic system, including anterior cingulate gyrus, insular lobe, basal ganglions, including thalamus, caudate nucleus and amygdaloid nucleus decreased significantly in AD group, compared to MCI and HC groups (p < 0.05 to p < 0.001). (3) The rCMRglc of many parts of brain such as frontal lobe, temporal lobe, parietal lobe, limbic system, and basal ganglions in MCI group was lower than that in HC group, but not significantly (p > 0.05). Only that of the left caudate nucleus in MCI decreased significantly compared to that in HC group (p < 0.05). CONCLUSION: Decreasing of rCMRglc of parietal lobe is sensitive in evaluating cognitive function, next one is temporal lobe, and then frontal lobe. The rCMRglc of frontal lobe, temporal lobe, parietal lobe, limbic system, and basal ganglions decreasing markedly indicates that global function decayed in AD patients. While the rCMRglc of those parts in MCI patients' brain decreases mildly. This indicates that MCI is the middle state of AD and HC. Decreasing of rCMRglc of the left caudate nucleus has a certain role in diagnosis of MCI.

Aged↗

PubMed2002

Alpha-2 macroglobulin I1000 V polymorphism in Chinese sporadic Alzheimer's disease and Parkinson's disease.

Several lines of evidence have revealed some overlapping pathologies in Alzheimer's disease (AD) and Parkinson's disease (PD). Although the alpha-2 macroglobulin gene (A2M) might be a risk factor of these two neurodegenerative diseases, conclusions from different studies have remained conflicting. Here we studied the role of A2M I1000 V polymorphism in both AD and PD in a Chinese Han population. We found that the A2M I/V genotype is associated with both AD (odds ratio (OR)=2.55, 95% confidential interval (95% CI): 1.20-5.43, attributable fraction (AF)=13.65%) and PD (OR=3.03, 95% CI: 1.30-7.02, AF=16.51%). After classifying according to the age of onset, this association is only detected in early-onset AD patients (OR=3.96, 95% CI: 1.28-12.26) and late-onset PD patients (OR=2.61, 95% CI: 0.97-7.09). Therefore, we conclude that in our samples, the A2M I/V genotype might be a susceptibility variant, even with minor effect, for both sporadic AD and PD.

Adult↗

PubMed2002

[The impact of depressive symptoms on psychological and physical outcomes: a 5-year follow-up study of elderly at the community level].

OBJECTIVE: To explore the impact of depressive symptoms on psychological and physical outcomes among elderly living in the residential areas. METHODS: A five years follow-up survey of health outcome was carried out among people aged 55 years or above in community without dementia. The outcome measurements included CES-D (center for epidemiological survey, depression scale), MMSE (mini-mental state examination), ADL (activity of daily living), LSIA (life satisfaction index A), index of physical disease and self-rated health questionnaire. A multiple regression analysis was administered to explore the correlation between depressive symptoms and indices of psychological and physical outcomes. RESULTS: (1) Data from 2 927 subjects having completed two surveys were analyzed. Baseline data showed significant distribution difference of MMSE, ADL, gender and education among the four CES-D score levels. (2) No significant correlation between CES-D score at baseline and MMSE, ADL, LSIA score at five-year follow up was found after controlling the age, gender, educational level and baseline score of MMSE and ADL. (3) Self-rated general health and memory change were significantly correlated to baseline CESD score under controlling the effects of other baseline variables. (4) The score of CESD was found to be a significant predictor for risks of physical disease and mortality by logistic regression model. The odds ratios were 1.52 (95% CI: 1.19 - 1.95) and 2.68 (95% CI: 1.41 - 5.06) respectively. CONCLUSION: Depressive symptoms play an important role on both psychological and physical health outcomes among elderly living in the community.

Aged↗

PubMedDate not supplied

Numerical investigation on hydrodynamics and biocompatibility of a magnetically suspended axial blood pump.

A newly designed magnetically suspended axial blood pump is presented, in which a 5 degrees-of-freedom rotor is suspended by using two conical active magnetic bearings, each with a four-pole stator. The preferred configuration could provide a rather large moment of inertia to increase the rotating stability of the suspended rotor in the pump. The hydrodynamic performance and internal flow fields in the pump are investigated by computational fluid dynamics. The pump head flow characteristics and the efficiency-Q curves at various rotating speeds are obtained, and the detailed flow fields in the pump are determined numerically. The distribution of shear stress, including Reynolds shear stress, is studied and discussed. Also, special attention is given to the small clearance between the rotor and the pump shell where the reversed secondary flow is formed and can flush out the clearance to avoid the flow stagnations. The secondary flow as well as the magnetic bearings can reduce thrombus in the pump. To check the biocompatibility of the pump further, the hemolysis indexes of the pump are estimated on the basis of the computed results.

Blood Pressure↗