BACKGROUND: Bone marrow mesenchymal stem cells (MSCs) have been widely accepted by medical investigators due to their advantages including easy obtaining, minimal invasion, with infinite proliferation and multi-differential potential, and without immunological rejection in the autologous transplantation. OBJECTIVE: The goal of this study is to isolate and purify rat bone marrow MSCs in vitro, so as to observe the effects of different concentrations of serum containing kidney-tonifying and blood-activating Chinese herbs on the in vitro proliferation of rat bone marrow MSCs.DESIGN: A randomized controlled animal experiment.SETTING: Hip Center, First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine.MATERIALS: Forty healthy male SD rats of SPF grade, weighing 170 to 180 g, were provided by the Laboratory Animal Center, Guangzhou University of Traditional Chinese Medicine. The protocol was performed in accordance with ethics guidelines for the use and care of animals. The involved rats were divided into 4 groups by random digit table with 10 rats in each: normal control group, high-, middle-, and low-concentration groups. METHODS: This study was performed at the Laboratory Animal Center, Guangzhou University of Traditional Chinese Medicine between January and March 2005. Rat bone marrow MSCs were isolated and purified by Percoll density gradient centrifugation, and cultured in vitro to establish rat bone marrow MSCs culture system. Rats in the high-, middle-, and low-concentration groups were intragastrically administrated with 4.4, 2.2 and 1.1 g/kg serum containing kidney-tonifying and blood-activating Chinese herbs, which equaled to 20, 10 and 5 times of adult dosage, respectively. Rats in the normal control group were intragastrically administrated with purified water for 1 week. One hour after the last administration, 6 mL blood was taken from abdominal aorta of each rat under the aseptic condition. Then, it was centrifuged at 2 000 r/min for 15 minutes, and meanwhile serum was collected. 10% rat serum containing kidney-tonifying and blood-activating Chinese herbs was added to the medium in the high-, middle-, and low-concentration groups, while 10% fetal bovine serum was added in the normal control group. MAIN OUTCOME MEASURES: ① MSCs growth status; ② MSCs morphology was observed by HE staining and Giemsa's staining; ③ MSCs antigen expression was detected by an immunocytochemical method; ④ Effects of different concentrations of serum containing kidney-tonifying and blood-activating Chinese herbs on MSCs growth.RESULTS: ①The primarily cultured bone marrow MSCs began to adhere to the wall 24 hours later and 80% of them reached the confluence 7 days later. ② MSCs took appearance in long shuttle shape or polygon. These cells were little. Nuclei were located in the middle part of cells or a little deviation. The ratio of nucleus to cytoplasm was a little high. ③CD44 expression was found in the cytoplasm of mononuclear cells, and colored blue. Partial MSCs expressed c-Kit. Their cytomorphology and phenotypic expression have the characteristics of MSCs. ④Three days after serum containing kidney-tonifying and blood-activating Chinese herbal medicine being added to high-, middle-, and low-concentration groups, the number of bone marrow MSCs was dose-dependently increased as compared with that in the normal control group. CONCLUSION: Serum containing kidney-tonifying and blood-activating Chinese herbs promotes the in vitro proliferation of bone marrow MSCs.

The aim of the present study was to investigate the effects and mechanisms of quercetin on plantar incision-induced matrix metalloproteinase (MMP)-9 and MMP-2 activity,microglia activation and the analgesic effect of quercetin on plantar incision surgery-treated mice.Postoperative pain model was mediated by plantar incision surgery and Von Frey Hairs was used to test the mechanical pain threshold.The activity of MMP-9 and MMP-2 in spinal cord was evaluated by gelatin zymography.The marker of microglia ionized calcium binding adapter molecule 1 (IBA-1),phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) was detected by Western blot.Results showed that quercetin (20,40,80 mg/kg,ip) significantly inhibited plantar incisioninduced mechanical allodynia and suppressed the activity of MMP-9 and MMP-2 in the spinal cord.Moreover,quercetin also markedly inhibited plantar incision-induced up-regulation of IBA-1 and p-p38 in spinal cord.In conclusion,quercetin may alleviate postoperative pain by suppressing MMP-9 and MMP-2 activity in microglia.

Objective To explore the possible effects of methyl methanesulfonate sensitive 2(MMS2)in the process of angiotensin Ⅱ inducing differentiation of neural stem cells (NSCs) into dopaminegic phenotype neurons. Methods NSCs were isolated from the brain of newborn rats and were cultured in the serum-free medium.Identification of neural precursor cells was done by Nestin immunocyt ochemical staining. Then the second generation of NSCs was divided into the following six groups: A, control; B, AⅡ; C, AT1 antagonist ZD7155; D, ZD7155+AⅡ; E, AT2 antagonist PD123319; F, PD123319+AⅡ. The detection of expression of MMS2 and TH mRNA level was done by real-time PCR. The silence of the expression of MMS2 in NSCs was brought about via the transfection of MMS2-siRNA, and then the NSCs were induced to differentiate into dopaminegic neurons. The expression of TH mRNA level in the cells of the groups after transfection was detected by real-time PCR. Results Nestin-positive cells were observed in suspended growth in the medium.Real-Time PCR revealed that the MMS2 and TH mRNA expression of group B and D were significantly higher than that of the control group(P<0.05), There was no significant difference in MMS2 and TH mRNA expression between group C, E, F and the control, respectively. Conclusion AⅡ increased the expression of MMS2 mRNA in NSCs and induced the differentiation of NSCs into DA neurons via AT2 recepter. MMS2 may play important roles in the process of angiotensin Ⅱ inducing NSCs to differentiate into dopaminergic neurons.

Objective:To study the inhibitory effect of γδT cells on the proliferation of ovarian cancer SKOV3 cells,and to clarify its possible mechanism of inducing apoptosis. Methods:The human ovarian cancer SKOV3 cells cultured in vitro were used as control group,and theγδT and SKOV3 cells were co-cultured for 72 h as γδT cells treatment group.Laser scanning confocal microscope was used to obeserve the morphological changes of nucleus SKOV3 cells,and the inhibitory rate of proliferation of SKOV3 cells in two groups were detected by MTT method;Transwell Chambers was used to detect the cell migration ability,then the apoptotic rates of SKOV3 cells were tested by flow cytometry (FCM).Results:The apoptotic morphology of nucleus of SKOV3 cells in γδT cells treatment group were found under microscope,such as nuclear shrinkage.The MTT resultes displayed that the inhibitory rate of proliferation of SKOV3 cells in γδT cells treatment group was higher than that in control group (P <0.05).The Transwell Chambers results showed that the number of transmembrane cells in γδT cells treatment group was lower than that in control group,and the migration rate was decreased compared with control group (P <0.05).The FCM results showed that the apoptotic rate of SKOV3 cells in γδT cells treatment group was higher than that in control group (P < 0.05 ).Conclusion:γδT cells can inhibit the proliferation and the migration abilities of ovarian cancer SKOV3 cells,and promote the apoptosis.

Objective:To investigate the efficacy of recapping laminoplasty preserving the continuity of superior spinous ligament in the treatment of benign tumors in the lumbar spinal canal.Methods:A retrospective analysis was performed. The clinical data of 23 patients with benign tumors in lumbar spinal canal, admitted to our hospital from March 2018 to March 2020, were collected. Follow up was performed for 12-23 months; Japanese Orthopaedic Association (JOA) scores were used for efficacy evaluation. X-ray, CT and MRI were used for imaging evaluation.Results:The number of replanted lamina was 1-4, with an average of 2.2. The surgical duration was (77.2±22.7) min, ranged from 67 min to 146 min; and the amount of intraoperative bleeding was (127±32.6) mL, ranged from 90-290 mL. The tumors were completely removed in all patients, and there were 2 patients complicated with cerebrospinal fluid leakage, and the wound healed after electrolyte supplement and local pressure treatment. No spinal cord injury, epidural hematoma, infection or other related complications were noted. The JOA scores increased from 11.85±1.38 before surgery to 23.22±2.47 at the last follow-up, with significant difference ( t=18.505, P<0.001). Of them, 10 had excellent efficacy, 9 had good efficacy, and 4 had medium efficacy, enjoying an excellent and good rate of 82.6%. Lumbar lordosis angle (LLA) was (51.58±2.39)°at the last follow-up, which showed no significant difference as compared with the preoperative LLA ([52.24±3.17]°, t=0.672, P=0.505). Imaging results showed that there was no spondylolisthesis or instability of lumbar spine, no recurrence of tumors was noted, and no displacement of lamina or secondary reduction of spinal canal volume were noted. Conclusion:The treatment of benign tumors in lumbar spinal canal by modified recapping laminoplasty preserving the continuity of superior spinous ligament can restore the normal anatomical structure of lumbar spinal canal, achieve no bone loss and maintain lumbar curvature well.

The new business forms are the new patterns of the job market extended by the use of mobile internet, big data, cloud computing, and other information technologies in the context of a new round of information technology development. In recent years, under the catalysis of the new employment model, a large number of new business employees have emerged such as food delivery riders, couriers, and online car-hailing drivers, whose employment forms are flexible and don’t fully conform to the establishment of labor relations with the employers, and whose problem of overtime work is common. The employment characteristics of new business forms of "focusing on performance and ignoring responsibility" make workers at great risks of occupational injuries and occupational health problems such as work-related musculoskeletal disorders, mental disorders, and overwork. However, the current research on occupational safety and health of workers in new business forms is insufficient, and the experience of institutional practice and supervision is also limited. Therefore, based on relevant research progress at home and abroad, this paper discussed the health injuries of workers in new business forms, summarized associated influencing factors from four aspects: employment form, employment affiliation, long working hours exposure, and institutional guarantee, and then proposed countermeasures to strengthen occupational safety and health protection of workers. For the current problems in the employment of new business forms, the government, enterprises, and workers need to work together to improve the legal and regulatory system for employment of new business forms, and standardize occupational safety and health management, thus effectively protect the occupational safety and health rights and interests of workers in new business forms.

Since its founding 100 years ago, the Communist Party of China (CPC) has attached great importance to the occupational health of workers, and closely linked the safeguard of occupational safety and health of workers with the missions of leading the people to stand up, get rich, and become strong. Based on this, the achievements of occupational health work made under the leadership of the CPC since the new democratic revolution, socialist revolution and construction, the new period of reform and opening up and socialist modernization, and socialism with Chinese characteristics for a new era were summarized, so as to provide reference for understanding the legacy of China's occupational health undertaking, and innovating to create the future.

Lipids are important components of living organisms that participate in and regulate a variety of life activities. Lipids in plants also play important physiological functions in response to a variety of abiotic stresses (e.g. salt stress, drought stress, temperature stress). However, most research on lipids focused on animal cells and medical fields, while the functions of lipids in plants were overlooked. With the rapid development of "omics" technologies and biotechnology, the lipidomics has received much attention in recent years because it can reveal the composition and function of lipids in a deep and comprehensive way. This review summarizes the recent advances in the functions and classification of lipids, the development of lipidomics technology, and the responses of plant lipids against drought stress, salt stress and temperature stress. In addition, challenges and prospects were proposed for future lipidomics research and further exploration of the physiological functions of lipids in plant stress resistance.
Droughts ; Gene Expression Regulation, Plant ; Lipids ; Plants ; Stress, Physiological