Objective:To explore the effects of microRNA-126 (miR-126) on the proliferation of human myeloid leukemia mononuclear cells (THP-1)-derived macrophages in high glucose environment and the regulatory role of miR-126 in periodontitis with diabetes.Methods:THP-1 cells were cultured in vitro and 5 &mu;g/L phorbol-12-myristate-13-acetate was applied to induce THP-1 cells differentiating into macrophages for 48 h in low glucose culture medium (5.5 mmol/L). THP-1-derived macrophages were then cultured with low glucose, medium glucose (15 mmol/L) or high glucose (25 mmol/L) media respectively. The proliferation of THP-1-derived macrophages was detected by cell counting kit-8 (CCK-8) method and the expressions of miR-126 and proliferation-associated factors were detected by quantitative real time PCR (qRT-PCR). The miR-126 mimic or inhibitor was transfected into THP-1-derived macrophages for 72 h. The proliferation of cells was detected by CCK-8 method and the expressions of miR-126 or proliferation-associated factors were detected by qRT-PCR. Results:Increasing glucose concentration decreased the proliferation of THP-1-derived macrophages (day 7, A values in low, medium and high glucose groups were 0.369±0.014, 0.214±0.009 and 0.200±0.010, respectively, P<0.01) as well as the survival rate ( P<0.05), promoted the expression of miR-126, B-cell lymphoma-2 (Bcl-2)-associated X protein (BAX) and caspase-3 ( P<0.05), and suppressed Bcl-2, phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2) expression ( P<0.05). After the miR-126 mimic was transfected in cells in low glucose medium for 72 h, compared with negative control (1.005±0.118), the expression of miR-126 significantly increased (2 980.227±170.431, P<0.05), and the proliferation of THP-1 derived macrophages decreased (negative control: 1.816±0.013, mimic group: 1.310±0.048, P<0.01), the level of BAX and caspase-3 significantly increased ( P<0.01, P<0.05), PIK3R2 and Bcl-2 significantly decreased ( P<0.05, P<0.01). After the miR-126 inhibitor was transfected in cells cultured in high glucose medium for 72 h, compared with negative control (0.723±0.133), the proliferation of inhibitor group increased (0.984±0.049, P<0.05), the level of BAX and caspase-3 significantly decreased ( P<0.01, P<0.05), PIK3R2 and Bcl-2 significantly increased ( P<0.01, P<0.05). Conclusions:High glucose condition can inhibit the proliferation of THP-1-derived macrophages and increase the expression of miR-126. MiR-126 can inhibit the proliferation of THP-1-derived macrophages in high glucose environment through up-regulating the expression of BAX and caspase-3 and down-regulating the expression of PIK3R2 and Bcl-2.

Objective:To investigate the synergistic effect of sarcopenia and osteoporosis on the occurrence of spinal osteoporotic fracture (OPF) in patients with rheumatoid arthritis (RA).Methods:A total of 389 hospitalized RA patients and 156 age and sex-matched normal subjects (control group) were recruited. Dual energy X-ray absorptiometry (DEXA) method was used to measure bone mineral density (BMD) of lumbar spine and hip, and bioelectrical impedance method was applied to determine skeletal muscle mass of limbs. X-ray examination of spin was conducted and spinal OPF was diagnosed according to semi-quality method. Student's t test was used for comparison of measurement date between the two groups, χ2 test was used for comparison of intergroup rates, and Logistic Regression(Backward LR) method was used for multivariate Regression analysis of binomial classification data. Results:BMD of all test sites in RA patients was significantly lower than that in the control group ( P<0.01). The incidence of total OP in RA group was significantly higher than that in the control group [(32.9% vs 12.8%), χ2=22.706, P<0.01]. A total of 84 patients with RA developed spinal OPF, with an incidence of 21.6% which was higher than that in the control group [(3.8%), χ2=25.439, P<0.01]. The incidence of sarcopenia in RA was 54.8%, significantly higher than that in the control group [(9.6%), χ2=93.241, P<0.01]. The incidence of sarcopenia combined with osteoporosis in RA group (28.5%) was significantly higher than that in the control group [(5.8%), χ2=118.110, P<0.01]. Comparison of the incidence of spinal OPF in RA patients among groups with different bone mass (normal bone mass, osteopenia, osteoporosis) showed that the incidence of spinal OPF among these groups was statistically different ( χ2=43.373, P<0.01), and the incidence of spinal OPF increased along with the decrease of bone mass ( χ2=43.003, P<0.01). The incidence of spinal OPF in RA patients with sarcopenia (27.2%, 58/213) was significantly higher than that in RA patients without sarcopenia [(14.8%, 26/176), χ2=8.833, P=0.003]. All participants were divided into three groups: group 1=no OP and sarcopenia, group 2=with sarcopenia or OP, group 3=both sarcopenia and OP. Difference of incidence of spine OPF in RA patients among three groups was statistically significant ( χ2=33.832, P<0.01), and the incidence of spinal OPF raised gradually in group 1 and 3, ( χ2=37.164, P<0.01). Incidences of sarcopenia, OP and spinal OPF in RA treated with glucocorticoid (GC) were higher than those in RA without GC ( P<0.05, P<0.01). Results of logistic regression showed advanced age[ OR(95% CI)=1.069(1.038, 1.101), P<0.01], usage of GC [ OR(95% CI)=3.169(1.679, 5.984), P<0.01] and sarcopenia combined with OP [ OR(95% CI)=2.113(1.430, 3.124), P<0.01] were risk factors for spinal OPF in RA patients. Conclusion:Incidences of sarcopenia, OP and spinal OPF in RA patients are higher than that in normal controls. Sarcopenia and OP have a synergistic effect on spinal OPF in RA patients.

Biosafety is an important guarantee of the new coronavirus laboratory test. The accident treatment of sample overflow and sprinkle is a necessary part of the emergency plan for testing activities. Beijing Preventive Medicine Association coordinated biosafety experts of COVID-19 laboratories from Beijing CDC, to write up "The standard for handling of accidents of corona virus disease 2019 sample (T/BPMA 0005-2020)" . The group standard was based on the guidelines of China and WHO, and combined with the practical experience of COVID-19 epidemic and the principle of "scientific, normative, applicable and feasible" . Through all kinds of risk Assessment, it included the spillover of samples caused by the packing of COVID-19 (highly pathogenic) samples, the overflow and sprinkle in the laboratory during the detection operation, and the spillage accident occurred during the transfer of samples in the same building. The standard could guide and standardize the handling methods of accidental overflow and sprinkle that may occur in the SARS-CoV-2 testing laboratories in the city.