A study of brain networks associated with Freezing of gait in Parkinson's disease using transfer entropy analysis.

BACKGROUND: Parkinson's disease (PD) is a common neurodegenerative disease in the elderly. Freezing of Gait (FOG) is one of the common motor symptoms of PD, but the potential mechanism remains unclear. This study aimed to investigate the changes of brain functional network topology in PD patients with FOG. METHODS: The resting electroencephalogram (EEG) were acquired from15 PD patients with FOG (PD-FOG), 13 PD patients without FOG (PD-nFOG), and 16 healthy control (HC). Cognitive and motor functions were assessed using subjective scales. The whole-brain functional networks were constructed based on transfer entropy. Transfer entropy was used to analyse the information flow and causality in the network and the network connectivity was analyzed by graph theory. The characteristics of PD-FOG and PD-nFOG were compared by receiver operator characteristic (ROC) curve analysis. RESULTS: The θ bands brain network of PD-FOG, PD-nFOG and HC group was significantly different (P < 0.05). The average characteristic path length of the θ bands brain network was positively correlated with FOG Questionnaire (FOGQ). PD-FOG and PD-nFOG get high classification accuracy according to this feature. The information inflow in the frontal and occipital lobes and information outflow in the temporal lobe of PD-FOG patients in the θ bands increased significantly. CONCLUSIONS: The whole-brain functional network characteristics of PD-FOG in the θ bands can serve as potential biomarkers for early diagnosis of PD-FOG. Abnormal information flow of the frontal, occipital, and temporal lobes in the θ bands may be an important factor leading to FOG.

Investigating PM2.5 responses to other air pollutants and meteorological factors across multiple temporal scales.

It remains unclear on how PM2.5 interacts with other air pollutants and meteorological factors at different temporal scales, while such knowledge is crucial to address the air pollution issue more effectively. In this study, we explored such interaction at various temporal scales, taking the city of Nanjing, China as a case study. The ensemble empirical mode decomposition (EEMD) method was applied to decompose time series data of PM2.5, five other air pollutants, and six meteorological factors, as well as their correlations were examined at the daily and monthly scales. The study results show that the original PM2.5 concentration significantly exhibited non-linear downward trend, while the decomposed time series of PM2.5 concentration by EEMD followed daily and monthly cycles. The temporal pattern of PM10, SO2 and NO2 is synchronous with that of PM2.5. At both daily and monthly scales, PM2.5 was positively correlated with CO and negatively correlated with 24-h cumulative precipitation. At the daily scale, PM2.5 was positively correlated with O3, daily maximum and minimum temperature, and negatively correlated with atmospheric pressure, while the correlation pattern was opposite at the monthly scale.

[Advances in hydrogen sulfide and hydrogen sulfide-releasing drugs].

Hydrogen sulfide (H(2)S) is considered as a new member of gasotransmitter family, following nitric oxide (NO) and carbon monoxide (CO). H2S exerts important biological effects in mammals, which has drawn more and more attention in recent years. It is proved that H(2)S has a role in the regulation of physiological and pathophysiological processes in the cardiovascular system and the nervous system. Several cardiovascular and nervous diseases are connected to H(2)S. H(2)S-releasing agents (also known as H(2)S donors) have been widely used not only as useful research tools but also potential therapeutic agents. In this review, we provide an overview of the chemistry and biology of H(2)S, and summarize the chemistry and biological activity of some natural and synthetic H(2)S donors. We introduce the developments of currently available H(2)S-releasing drugs including H(2)S-non-steroidal anti-inflammatory drugs, H(2)S-nervous system drugs and NO-H(2)S-releasing drugs. We hope this review will be a value reference in the development of H(2)S-releasing drugs in the treatment of cardiovascular and nervous diseases.

Synthesis and biological evaluation of nitric oxide (NO)-hydrogen sulfide (H2S) releasing derivatives of (S)-3-n-butylphthalide as potential antiplatelet agents.

In the present study, a series of novel nitric oxide-hydrogen sulfide releasing derivatives of (S)-3-n-butylphthalide ((S)-NBP) were designed, synthesized, and evaluated as potential antiplatelet agents. Compound NOSH-NBP-5 displayed the strongest activity in inhibiting the arachidonic acid (AA)- and adenosine diphosphate (ADP)-induced platelet aggregation in vitro, with 3.8- and 7.0-fold more effectiveness than (S)-NBP, respectively. Furthermore, NOSH-NBP-5 could release moderate levels of NO and H2S, which would be beneficial in improving cardiovascular and cerebral circulation. Moreover, NOSH-NBP-5 could release (S)-NBP when incubated with rat brain homogenate. In conclusion, these findings may provide new insights into the development of novel antiplatelet agents for the treatment of thrombosis-related ischemic stroke.