Biomarkers are urgently needed for the diagnosis and monitoring of disease progression in Parkinson's disease. Both DJ-1 and alpha-synuclein, two proteins critically involved in Parkinson's disease pathogenesis, have been tested as disease biomarkers in several recent studies with inconsistent results. These have been largely due to variation in the protein species detected by different antibodies, limited numbers of patients in some studies, or inadequate control of several important variables. In this study, the nature of DJ-1 and alpha-synuclein in human cerebrospinal fluid was studied by a combination of western blotting, gel filtration and mass spectrometry. Sensitive and quantitative Luminex assays detecting most, if not all, species of DJ-1 and alpha-synuclein in human cerebrospinal fluid were established. Cerebrospinal fluid concentrations of DJ-1 and alpha-synuclein from 117 patients with Parkinson's disease, 132 healthy individuals and 50 patients with Alzheimer's disease were analysed using newly developed, highly sensitive Luminex technology while controlling for several major confounders. A total of 299 individuals and 389 samples were analysed. The results showed that cerebrospinal fluid DJ-1 and alpha-synuclein levels were dependent on age and influenced by the extent of blood contamination in cerebrospinal fluid. Both DJ-1 and alpha-synuclein levels were decreased in Parkinson's patients versus controls or Alzheimer's patients when blood contamination was controlled for. In the population aged > or = 65 years, when cut-off values of 40 and 0.5 ng/ml were chosen for DJ-1 and alpha-synuclein, respectively, the sensitivity and specificity for patients with Parkinson's disease versus controls were 90 and 70% for DJ-1, and 92 and 58% for alpha-synuclein. A combination of the two markers did not enhance the test performance. There was no association between DJ-1 or alpha-synuclein and the severity of Parkinson's disease. Taken together, this represents the largest scale study for DJ-1 or alpha-synuclein in human cerebrospinal fluid so far, while using newly established sensitive Luminex assays, with controls for multiple variables. We have demonstrated that total DJ-1 and alpha-synuclein in human cerebrospinal fluid are helpful diagnostic markers for Parkinson's disease, if variables such as blood contamination and age are taken into consideration.

Disasters and pandemics pose unique challenges to health care delivery. As health care resources continue to be stretched due to the increasing burden of the coronavirus disease (COVID-19) pandemic, telemedicine, including tele-education, may be an effective way to rationally allocate medical resources. During the COVID-19 pandemic, a multimodal telemedicine network in Sichuan Province in Western China was activated immediately after the first outbreak in January 2020. The network synergizes a newly established 5G service, a smartphone app, and an existing telemedicine system. Telemedicine was demonstrated to be feasible, acceptable, and effective in Western China, and allowed for significant improvements in health care outcomes. The success of telemedicine here may be a useful reference for other parts of the world.

DJ-1 and α-synuclein are leading biomarkers for Parkinson disease diagnosis and/or monitoring disease progression. A few recent investigations have determined DJ-1 and α-synuclein levels in plasma or serum, a more convenient sample source than cerebrospinal fluid; but the results were variable or even contradictory. Besides limitations in detection technology and limited number of cases in some studies, inadequate control of several important confounders likely has contributed to these inconsistent results. In this study, the relative contribution of each blood component to blood DJ-1 and α-synuclein was evaluated, followed by quantification of plasma levels of both markers in a larger cohort of patients/subjects (~300 cases) whose cerebrospinal fluid DJ-1 and α-synuclein levels have been determined recently. The results demonstrated that the DJ-1 and α-synuclein in blood resided predominantly in red blood cells (>95%), followed by platelets (1-4%), white blood cells and plasma (≤1%), indicating that variations in hemolysis and/or platelet contamination could have a significant effect on plasma/serum DJ-1 and α-synuclein levels. Nonetheless, after adjusting for the age, although there was a trend of decrease in DJ-1 and α-synuclein in patients with Parkinson or Alzheimer disease compared with healthy controls, no statistical difference was observed in this cohort between any groups, even when the extent of hemolysis and platelet contamination were controlled for. Additionally, no correlation between DJ-1 or α-synuclein and Parkinson disease severity was identified. In conclusion, unlike in cerebrospinal fluid, total DJ-1 or α-synuclein in plasma alone is not useful as biomarkers for Parkinson disease diagnosis or progression/severity.

Background: To establish a prospective cohort to enumerate the prevalence, incidence and risk factors for dementia and mild cognitive impairment (MCI) among residents aged ≥60 in an urban community of Shanghai, China. Methods: Participants received clinical evaluations including physical measurements, demographic and lifestyle questionnaires, physical and neurologic examinations, and neuropsychological testing. Urine and blood samples were collected, aliquoted, and stored. DNA was extracted for Apolipoprotein (APOE) genotyping. Diagnoses of dementia and MCI were made using standard criteria via consensus diagnosis. Results: Among 3,141 participants aged ≥60, 1,438 (45.8%) were men. The average age of participants was 72.3 years (SD 8.1), and they had an average of 11.6 years (SD 4.4) of education. The most common chronic disease of participants was hypertension (56.4%). The frequencies of APOE-​ε2, ε3 and ε4 were 7.9, 82.7 and 9.4%, respectively. We diagnosed 156 (5.0%, 95% CI 4.3-5.8%) participants with dementia. The prevalence rates of Alzheimer's disease and vascular dementia were 3.6% (95% CI 3.0-4.3%) and 0.8% (95% CI 0.5-1.1%). Conclusions: The Shanghai Aging Study is the first prospective community-based cohort study of cognitive impairment in China, with a comparable study design, procedures, and diagnostic criteria for dementia and MCI to most previous cohort studies in developed countries.