BACKGROUND: Physical activity, sedentary behavior (SB), and sleep duration are associated with brain health. Effects of those on developing Parkinson's disease (PD) are poorly investigated. This study aimed to examine the independent and joint associations of physical activity, SB, sleep with PD risk. METHODS: We analyzed data on 401,697 participants from the UK Biobank cohort, which was enrolled in 2006-2010. Physical activities were measured based on a questionnaire. Sleep and SB time were defined through self-reported total number of hours. Models fitted with restricted cubic spline were conducted to test for linear and non-linear shapes of each association. Cox proportional hazards regression models were used to estimate the association of three modifiable behaviors. RESULTS: Our analytic sample included 401,697 participants with 3030 identified cases of PD (mean age, 63 years; 62.9% male). PD risk was 18% lower in the high total physical activity group (95% CI, 0.75-0.90), 22% lower in the high leisure-time physical activity (LTPA) group (95% CI, 0.71-0.86) compared with the low level and 14% higher in the high sleep duration group (95% CI, 1.05-1.24) compared to moderate group. Total SB time was irrelevant with PD risk, while high TV viewing showed a 12% increase of PD risk compared to the low group (95% CI, 1.02-1.22). Low computer use (0 h/day) was associated with a 14% higher risk compared to 1 h/day use (95% CI, 1.04-1.26). Those associations were independent. A combination of 7 h/day sleep, moderate-to-high computer use, and moderate-to-vigorous intensity of LTPA showed lowest PD risk (HR, 0.70; 95% CI, 0.57-0.85). CONCLUSIONS Physical activity, SB, and sleep were associated with PD risks separately. Our findings emphasize the possibility for changing these three daily activities concurrently to lower the risk of PD. These findings may promote an active lifestyle for PD prevention.
Humans ; Parkinson Disease/physiopathology* ; Male ; Sedentary Behavior ; Female ; Middle Aged ; Exercise/physiology* ; Prospective Studies ; Sleep/physiology* ; Aged ; Surveys and Questionnaires ; Proportional Hazards Models ; Risk Factors

Objective To study the relationship of the tibial plateau subchondral trabecular bone (STB) microstructure and the cartilage degeneration with the lower limb alignment based on individual trabecula segmentation (ITS) and histology analysis in knee osteoarthritis (OA). Methods Hip-knee-ankle (HKA) angles were measured on the full-length lower extremity films of patients before total knee arthroplasty (TKA). The tibial plateau excised from the TKA were collected for micro-CT scanning and ITS analysis. The cartilage degeneration was evaluated by histology. The relationship between the HKA angle and the changes in microstructural parameters of STB and cartilage degeneration were analyzed. ResultsThe plate, rod and axial bone trabecular volume fraction (BV/TV, pBV/TV, pBV/TV), ratio of trabecular plate versus rod (P/R), plate trabecular number density (pTb.N), plate trabecular thickness (pTb.Th), trabecular plate surface area (pTb.S), trabecular rod length (rTb.L), and plate-plate and plate-rod junction density (P-P Junc.D, P-R Junc.D) of the subchondral bone of the tibial plateau were significantly related to the cartilage degeneration OARSI score and the HKA angle. The greater the deviation of the lower limb alignment, the greater the number of subchondral trabeculae, the thicker the trabeculae, the greater the bone mass, the stronger the connectivity, especially the plate trabeculae on the affected side of tibial plateau, and the higher the OARSI score of cartilage degeneration. Conclusions Abnormal lower limb alignment may cause abnormal microstructure of the plate and rod STB of the tibial plateau by changing the stress distribution of the knee, especially the significant increase and thickening of the plate trabecular and axial trabecular bone, which may be an important risk factor that further aggravates the degeneration of articular cartilage and the progress of OA. Therefore, lower limb alignment correction with surgical intervention and improving STB with bone metabolism agents may efficiently contribute to preventing cartilage damage and mitigate OA progression.

Objective: To prepare nano polypyrrole (PPy)/chitin composite membrane and observe their biocompatibility. Methods: The nano PPy was synthesized by microemulsion polymerization, blended with chitosan and then formed membranes. The membranes were then modified by acetylation to get the experimental membranes (nano PPy/chitin composite membranes, group A). The chitosan membranes (group B) and chitin ones (group C) modified by acetylation acted as control. Scanning electron microscopy and FT-IR spectra were used to identify the nano PPy and the membranes of each group. And the conductivity of membranes of each group was measured. Schwann cells were co-cultured in vitro with each group membranes to observe the biocompatibility by inverted microscope observing, living cell staining, cell counting, and immunofluorescence staining. The lysozyme solution was used to evaluate the degradation of the membranes in vitro. Results: The FT-IR spectra showed that the characteristic vibrational absorption peaks of C=C from nano PPy appeared at 1 543.4 cm -1 and 1 458.4 cm -1. Scanning electron microscopy observation revealed that the size of nano PPy particles was about 100-200 nm. The nano PPy particles were synthesized. It was successful to turn chitosan to chitin by the acetylation, which was investigated by FT-IR analysis of membranes in groups A and C. The characteristic peaks of the amide Ⅱ band around 1 562 cm -1 appeared after acetylated modification. Conductivity test showed that the conductivity of membranes in group A was about (1.259 2±0.005 7)×10 -3 S/cm, while the conductivity of the membranes in groups B and C was not detected. The nano PPy particles uniformly distributed on the surface of membranes in group A were observed by scanning electron microscope; the membranes in control groups were smooth. As a result, the nano PPy/chitin composite membranes with electrical conductivity were obtained. The cultured Schwann cells were found to survive with good function by fluorescein diacetate live cell staining, soluble protein-100 immunofluorescence staining, and inverted microscope observing. The cell counting showed that the proliferation of Schwann cells after 2 days and 4 days of group A was more than that of the two control groups, and the differences were significant ( P<0.05). It indicated that the nano PPy/chitin composite membranes had better ability of adhesion and proliferation than those of chitosan and chitin membranes. The degradation of membranes in vitro showed that the degradation rates of membranes in groups A and C were significantly higher than those in group B at all time points ( P<0.05). In a word, the degradation performance of the membranes modified by acetylation was better than that of chitosan membranes under the same condition. Conclusion: The nano PPy and chitosan can be blended and modified by acetylation successfully. Nano PPy/chitin composite membranes had electrical conductivity, degradability, and good biocompatibility in vitro.