[Complex mechanisms of chronic pain in knee osteoarthritis identified by neuroimaging technology].

Chronic pain of knee osteoarthritis (KOA) greatly affects the quality of life and functional activities of patients. It is important to clarify the underlying mechanisms of KOA pain and the analgesic effect of different therapies. Neuroimaging technology has been widely used in the basic and clinical research of pain. In the recent years, neuroimaging technology has played an important role in the basic and clinical research of KOA pain. Increasing evidence demonstrates that chronic pain in KOA includes both nociceptive and neuropathic pain. The neuropathic mechanism involved in KOA pain is complex, which may be caused by peripheral or central sensitization. In this paper, we review the regional changes of brain pathophysiology caused by KOA pain based on magnetic resonance imaging (MRI), electroencephalogram (EEG), magnetoencephalogram (MEG), near-infrared spectroscopy (NIRS) and other neuroimaging techniques. We also discuss the central analgesic mechanism of different KOA therapies, with a focus on the latest achievements in the evaluation and prediction of pain. We hope to provide new thoughts for the treatment of KOA pain, especially in the early and middle stages of KOA.

[Effects of manual loading on calcitonin gene-related peptide and nerve growth factor in rats with chronic low back pain].

OBJECTIVE: To observe the analgesic effect of manipulation loading on chronic low back pain (CLBP) model rats and the expression of inflammatory factors in psoas major muscle tissue, and to explore the improvement of manipulation on local inflammatory microenvironment. METHODS: Thirty two SPF male SD rats weighing 340-360g were randomly divided into blank group, sham operation group, chronic low back pain model group and treatment group, with 8 rats in each group. In the model group, L4-L6 lumbar vertebrae were implanted with external link fixation system (ELFS). After implantation of ELFS, the treatment group received manualintervention with 5N force and 2Hz frequency on both sides of the spine, 15 min / time, once a day, for 14 consecutive days. Paw with drawl threshold (PWT) and paw withdrawl latency (PWL) was measured before modeling and on the 1st, 3rd, 7th, 10th and 14th day after intervention. At the end of the treatment cycle, the concentrations of calcitonin gene-related peptide (CGRP) and nerve growth factor (NGF) in psoas muscle were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: There was no significant difference in PWT and PWL between the blank group and the sham operation group after modeling (P>0.05);after modeling, PWT and PWL in the CLBP model group and the treatment group were significantly decreased(P<0.01);PWT in the treatment group was not significantly improved than that in the CLBP model group on the 1st and 3rd day after manual loading(P>0.05);on the 7th day after manual loading, the pain threshold value in the treatment group was higher than that in the CLBP model group, but there was no significant difference There was no significant difference between the two groups (P=0.056>0.05). On the 10th and 14th day of treatment, the mechanical pain threshold of the treatment group began to rise, and it was statistically significant compared with CLBP model rats (P<0.05, P< 0.01);on the 1st and 3rd day after manual treatment, the PWL of the treatment group was not significantly improved compared with CLBP model group (P>0.05);on the 7th day, the PWL of the treatment group was significantly higher than that of CLBP model group, there was statistical significance (P=0.016<0.05). Manual loading improved thermal hyperalgesia in CLBP rats until the end of the experiment. The contents of CGRP and NGF in psoas major muscle of CLBP model group were higher than those of blank group and sham operation group (P<0.01). After treatment, the contents of CGRP and NGF decreased significantly(P<0.01). CONCLUSION: Local massage loading has analgesic effect on CLBP rats, at the same time, it can inhibit the content of CGRP and NGF in psoas muscle tissue of CLBP rats, and improve the local inflammatory microenvironment.

Effect of Fabrication Parameters on the Performance of 0.5 wt.% Graphene Nanoplates-Reinforced Aluminum Composites.

Aluminum composites reinforced by graphene nanoplates(GNP) with a mass fraction of 0.5% (0.5 wt.% GNP/Al) were fabricated using cold pressing and hot pressing. An orthogonal test was used to optimize the fabrication parameters. Ball milling time, ball milling speed, and ultrasonic time have the largest influence on the uniformity of the graphene in the composites. Afterwards, the microstructure, interfacial properties, and fracture morphology of the composites obtained with different parameters were further analyzed. The results show that ball milling time and ball milling speed have obvious influences on the mechanical properties of the composite. In this paper, when the ball milling speed is 300 r/min and the ball milling time is 6 h, the dispersion uniformity of graphene in the 0.5 wt.% GNP/Al composite is the best, the agglomeration is the lowest, and the mechanical properties of the composites are the best, among which the tensile strength is 156.8 MPa, 56.6% higher than that of pure aluminum fabricated by the same process (100.1 MPa), and the elongation is 19.9%, 39.8% lower than that of pure aluminum (33.1%).

[The moss Physcomitrella patens, a new model system for functional genomics].

The potential of moss as a model system to study plant biological process is associated with their relatively simple developmental pattern and the dominance of the haploid gametophyte in the life cycle. The moss Physcomitrella patens exhibits a very high rate of homologous recombination in its nuclear DNA, making gene targeting approaches in this plant as convenient as in yeast or in ES cells of mice. Sharing many biological features with higher plants and having many other advantages, the moss Physcomitrella patens will be an attractive model system for plant biology and functional genome analysis.