Association of Decreased Serum BDNF With Restless Legs Syndrome in Parkinson's Disease Patients.

Objective: To objective of the study was to investigate whether serum brain-derived neurotrophic factor (BDNF) levels are associated with the severity of restless legs syndrome (RLS) in Parkinson's disease (PD). Methods: A total of 249 PD patients with (n = 53) and without RLS (n = 196) and 326 age-matched controls were included in this study. All the serum BDNF levels of the participants were measured. The International Restless Legs Syndrome Study Group Rating Scale (IRLSSG-RS) was administered for the severity of RLS. The severity of PD patients were assessed by the Unified PD Rating Scale (UPDRS) and the Hoehn and Yahr (H-Y) stage. Results: The prevalence of RLS was significantly higher in PD patients (21.3%) than in the controls group (7.4%) (p < 0.05). The IRLSSG-RS score in PD patients with RLS (16.25 ± 5.24) was significantly increased than in controls with RLS (12.08 ± 3.99) (p < 0.01). The serum BDNF levels were significantly decreased in PD patients with RLS than in PD patients without RLS, controls without RLS, and controls with RLS (p < 0.001). BDNF levels were negatively associated with IRLSSG-RS in both PD patients with RLS and controls with RLS group (both p < 0.01). Multiple regression analysis confirmed that in either PD with RLS or controls with RLS group, BDNF was an independent contributor to IRLSSG-RS (both p < 0.01). Conclusions: Decreased serum BDNF levels may be involved in the pathophysiology of RLS in PD, suggesting that it may serve as a potential blood biomarker of diagnostic value for RLS in PD.

A new flavone C-glycoside and a new bibenzyl from Bulbophyllum retusiusculum.

A new flavone C-glycoside, apigenin 6-C-α-arabinofuranosyl 8-C-α-arabinopyranoside (1) and a new bibenzyl, bulbotetusine (2), were isolated from the tubers of Bulbophyllum retusiusculum. Their structures were established on the basis of extensive spectroscopic analyses. The absolute configuration of 2 was determined by the comparison of experimental and calculated electronic circular dichroism. Compounds 1 and 2 showed no obvious cytotoxic activity against any five human tumour cell lines with IC50 values >40 µM.

Fractional crystallization and homogeneous nucleation of confined PEG microdomains in PBS-PEG multiblock copolymers.

Fractional crystallization, homogeneous nucleation of poly(ethylene glycol) (PEG) segment, and self-nucleation behavior of PEG segment within miscible double crystalline poly(butylene succinate)-poly(ethylene glycol) (PBSEG) multiblock copolymers with different composition and segment chain length were studied by differential scanning calorimetry (DSC). Surface morphology of PBSEG10K with different PEG content was investigated by atomic force microscope (AFM). Different from di- or triblock copolymers, the microstructure and confinement of PEG dispersed phase in PBS matrix phase highly depends on chain length and sequence as well as segment content. The transition point of the PEG segment content from heterogeneous to homogeneous nucleation mechanism decreased from 50 to 39 wt % with PEG segment chain length increasing from 1000 to 2000 g/mol. When PEG segment chain length increased further to 6000 and 10000 g/mol, homogeneous nucleation phenomenon took place at much lower PEG content and fractional crystallization was observed at 29 and 24 wt %, respectively. Homogeneous nucleation mechanism of PBSEG(1K-36), PBSEG(2K-26), PBSEG(6K-19), and PBSEG(10K-12) was evidenced by the large supercoolings needed for crystallization, as well as first-order crystallization kinetics obtained. Self-nucleation behaviors of PEG segment still rely on the composition of PBSEGs. In the case of heterogeneous nucleation crystallization, self-nucleation behaviors of PEG segment showed standard self-nucleation behavior with classical three self-nucleation domains. When the crystallizable chains were confined into isolated microdomains, however, self-nucleation domain (domain II) disappeared. The absence of III(A) was observed in PBSEG(2K-39), while PBSEG(6K-29) had both III(A) and III(SA). Furthermore, AFM morphology studies still indicated the confined degree of PEG segment by previous PBS crystals was profoundly influenced by segment fraction. The confinement of the PEG segment by previous PBS edge-on lamellae was observed in the sample which displays a homogeneous nucleation crystallization behavior.

Urethane Ionic Groups Induced Rapid Crystallization of Biodegradable Poly(ethylene succinate).

Novel urethane ionic groups were incorporated into biodegradable poly(ethylene succinate) (PES) by chain extension reaction of PES diol (HO-PES-OH) and diethanolamine hydrochloride (DEAH) using hexamethylene diisocyanate (HDI) as a chain extender. The synthesized polymer was a novel segmented poly(ester urethane) ionomer (PESI) in which the soft segments were formed by reaction of HO-PES-OH with HDI and the hard segments that contained ionic groups were derived from reaction of DEAH with HDI. The crystallization rate of PESI was dramatically accelerated when 3 mol % urethane ionic groups were incorporated. However, the crystallization mechanism did not change. The significant acceleration in crystallization rate was attributed to the improved nucleation efficiency by incorporation of the urethane ionic group, because PESI showed significantly enhanced nucleation density but slightly slowed spherurlitic growth rate in comparison with PES which was synthesized by chain extension reaction of HO-PES-OH with HDI. The increased nucleation efficiency was ascribed to the aggregation of hard segments of PESI induced by the ionic interactions.