Abstract: Objective　To investigate the antimicrobial activity of omadacycline (OMC) against clinical Streptococcus agalactiae (GBS) isolates, as well as its relationship with biofilm formation, resistance genes and virulence genes. Methods　A total of 136 strains of Streptococcus agalactiae isolated from Shenzhen Nanshan People's Hospital between 2015 to 2020. The minimum inhibitory concentration (MIC) of OMC against Streptococcus agalactiae was determined by broth microdilution. Crystal violet staining was used to detect the biofilm formation ability of GBS. Resistance genes (tetM, tetO, tetK, ermB, OptrA) and virulence genes (cpsⅢ, bca, fbsA, cpsA, scpB) were investigated by polymerase chain reaction (PCR). Results　Among the 136 clinical isolates of GBS, 20 strains (14.7%) were resistant to OMC, 64 (47.1%) were intermediate, and 52 (38.2%) were sensitive. Fifty-seven strains (41.9%) were biofilm-positive, 20 of which (35.1%) were sensitive to OMC. Seventy-nine strains (58.1%) were biofilm-negative, 32 of which (40.5%) were susceptible to OMC. There was a statistically significant difference in the sensitivity rates between the two groups of strains (χ2=63.062, P<0.001), but there was no significant difference in the sensitivity of OMC among the biofilm-positive strains (Fisher's exact test, P=0.824). The resistance rates of tetM, tetO, ermB and OptrA positive strains were higher than those of negative strains, while tetK was opposite. The presence of tetM (Z=0.815, P=0.415), tetO (Z=0.151, P=0.88), tetK (Z=0.567, P=0.571), ermB (Z=1.198, P=0.231) resistance genes in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, the presence of the OptrA resistance gene showed a statistically significant effect on the sensitivity of OMC (Z=2.913, P=0.004). The virulence factors cpsⅢ, bca, fbsA, cpsA and scpB were all detected at a rate higher than 50%. The presence of the virulence genes cpsⅢ (Z=0.222, P=0.824), bca (Z=0.141, P=0.888), fbsA (Z=0.813, P=0.416), and cpsA (Z=1.615, P=0.106) in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, there was a significant inter-group difference in the scpB virulence gene (Z=2.844, P=0.004), but the rank mean values and resistance rates of scpB-positive strains were lower than those of the negative strains. Conclusions　The formation of biofilm in Streptococcus agalactiae reduces its sensitivity to OMC, but there was no significant difference in the sensitivity to OMC among the biofilm-positive strains. The presence of resistance genes tetM, tetO, tetK, ermB, and virulence genes cpsⅢ, bca, fbsA, cpsA, scpB in Streptococcus agalactiae is not associated with OMC resistance, but the presence of the resistance gene OptrA is correlated with OMC resistance..

Objective:To prepare specific molecular probe 18F-AlF-1, 4, 7-triazacylononane-1, 4, 7-triacetic acid-(polyethylene glycol) 4-ZD2 ( 18F-AlF-NOTA-PEG 4-ZD2) for targeting extradomain-B fibronectin (EDB-FN), and evaluate its properties in vitro and in vivo. Methods:18F-AlF-NOTA-PEG 4-ZD2 was prepared by one-step chelation labeling with Al 18F. The radiochemical purity and in vitro stability were determined by high performance liquid chromatography (HPLC). The partition coefficient (logP) of 18F-AlF-NOTA-PEG 4-ZD2 was evaluated, and the cell uptake experiment was carried out (triple-negative breast cancer (MDA-MB-231) cells (1×10 6/tube) were divided into 3 groups ( n=3 per group); positive group, inhibition group, control group). MicroPET imaging was performed on MDA-MB-231 bearing nude mice ( n=3) after 18F-AlF-NOTA-PEG 4-ZD2 injection (30, 60, 90, 120 min) and compared with blocking group ( n=3, NOTA-PEG 4-ZQ 2 was preinjected at 0.5 h before 18F-AIF-NOTA-PEG a-ZD2 injection). Independent-sample t test was used to analyze the data. Results:18F-AlF-NOTA-PEG 4-ZD2 was successfully prepared. The optimized radiochemical yield was (33.8±2.1)% (undecay corrected, n=8) and the radiochemical purity was >96%. After incubating 120 min at 37 ℃, the radiochemical purity of 18F-AlF-NOTA-PEG 4-ZD2 in human serum and PBS was >93%, indicating its good stability in vitro. The specific activity was (11.1±3.2) GBq/μmol, and logP was -1.43±0.05. The uptake value of tumor cells was (1.77±0.28) percentage applied activity (%AR)/10 6 cells at 120 min post-injection in positive group, and the total uptake value of the inhibition group was (0.76±0.07) %AR/10 6 cells ( t=4.30, P=0.032). MicroPET imaging in tumor bearing nude mice showed that 18F-AlF-NOTA-PEG 4-ZD2 was mainly metabolized by the liver and kidneys. The tumor uptake value was (1.94±0.21) percentage activity of injection dose per gram of tissue (%ID/g) at 60 min post-injection and the tumor/muscle ratio was 3.80±0.25 at 90 min post-injection in the experimental group, while the tumor uptake value of tumor bearing nude mice in the blocking group was (0.43±0.09) %ID/g at 60 min post-injection ( t=3.18, P=0.006). Conclusions:18F-AlF-NOTA-PEG 4-ZD2 can be prepared simply with high labeling rate and good stability in vitro, with high tumor uptake and tumor/muscle ratio in microPET imaging, and good specificity and long tumor residence time. The probe has good application prospect in breast cancer with high expression of fibronectin subtype EDB-FN.

Objective To investigate the applicability of clinical grade and a non-contact measurement method in evaluation of underneath eye wrinkles and to compare two methods.Methods A lot of 46 healthy Chinese women were recruited for this study.Underneath eye wrinkles severity was evaluated using clinical grade and a non-contact measurement method.The correlations were calculated for clinical grade and non-contact measurement parameters and age.The non-contact measurement parameters were classified by factor analysis.The correlations between age,clinical grade and factors were analyzed.Results The correlation coefficient between clinical grade in comparison to subject's age was 0.818.The parameters getting from non contact measurement were obviously correlated with age and clinical grade except SEr and SEsc;the correlation coefficients between parameters and age were-0.601 to 0.605;the correlation cofficients between parameters and clinical grade were-0.630 to 0.570.The non-contact measurement parameters could be classified into two factors;one represented wrinkle depth and roughness;the other represented wrinkle width and counts.These two factors were also obviously correlated with age and clinical grade.Conclusions Clinical grade and non contact measurement methods are both applicable in evaluation of underneath eye wrinkles.The parameters getting from two methods are obviously correlated with each other.

OBJECTIVETo explore the anesthetic effects of repeated administration of propofol combined with vitamin C in mice.

METHODSForty mice were subjected to daily intraperitoneal injections of 80 mg/kg propofol (P80 group), 70 mg/kg propofol and 50 mg/kg vitamin C (P70+Vc50 group), 55 mg/kg propofol and 100 mg/kg vitamin C (P55+Vc100 group), or 50 mg/kg propofol and 200 mg/kg vitamin C (P50+Vc200 group) for 6 consecutive days, and the anesthesia induction time and anesthesia duration were recorded.

RESULTSCompared with the P80 group, the mice in P55 + Vc100 group and P50 + Vc200 group showed significantly shorter anesthesia duration on the first 3 days (P<0.05). In all the groups, anesthesia duration was significantly shortened in the following days compared with that on day 1 (P<0.01); anesthesia duration was shorter on day 3 than on day 2 in P50 + Vc200 group (P<0.01), and was shorter on days 4, 5, and 6 than on day 2 in all the groups (P<0.01). In all the groups, the rate of loss of righting reflex (LORR) decreased gradually with time in a similar pattern.

CONCLUSIONVitamin C can reduce the dose of propofol without obviously affecting the anesthetic effect to reduce the incidence of drug tolerance and potential dose-related side effects of propofol.

Anesthesia ; Anesthesia Recovery Period ; Anesthetics, Intravenous ; administration & dosage ; pharmacology ; Animals ; Ascorbic Acid ; administration & dosage ; pharmacology ; Drug Tolerance ; Mice ; Propofol ; administration & dosage ; pharmacology

Objective To investigate the status and risk factors of surgical site infection (SSI)in hospitals in Chi-na,so as to provide theoretical basis for the prevention and treatment of SSI.Methods Four types of surgeries (colorectal surgery,abdominal hysterectomy,femoral neck repair surgery,and vascular surgery)in 29 hospitals were monitored prospectively,risk factors for SSI were analyzed.Results A total of 6 309 surgical procedures were investigated,incidence of SSI was 1 .60%.Incidences of SSI in patients receiving colorectal surgery,abdominal hys-terectomy,femoral neck repair surgery,and vascular surgery were 4.47%(74/1 655 ),1 .03%(22/2 139),0.21 %(5/2 372),and 0.00% (0/143 )respectively.The incidences of SSI were different among different regions (χ2 =114.213,P <0.05).The most common SSI was superficial incisional infection,the next was deep incisional infec-tion.The major pathogens causing SSI were Escherichia coli ,Enterococcus spp .,coagulase negative staphylococ-cus ,Staphylococcus aureus ,and Klebsiella pneumoniae .The independent risk factors for SSI were male patients, long duration of surgery,and high NNIS score.Conclusion The risk of SSI is varied with different types of surger-ies.Male,long duration of surgery,and high NNIS score can increase the risk of postoperative SSI.

Objective To explore the incidence of surgical site infection (SSI)and compliance to bundled interven-tion measures,and evaluate the effect of bundled interventions on controlling SSI.Methods From October 2013 to September 2014,three types of surgeries (colorectal surgery,abdominal hysterectomy,and femoral neck repair sur-gery)in 29 hospitals in China were monitored,October 2013 to March 2014 was baseline investigated stage,April 2014 to September 2014 was intervention stage.Results A total of 6 166 episodes of surgeries were monitored,the incidence of SSI was 1 .64%,incidence of SSI following colorectal surgery,abdominal hysterectomy,and femoral neck repair surgery were 4.47%,1 .03%,and 0.21 % respectively.The P 75 time of three types of surgeries were 3,2,and 2 hours respectively.Compared with the baseline stage,the compliance to most intervention measures im-proved after intervention,the largest increase in the compliance to interventions was disinfection with chlorhexidine-containing disinfectant at surgical sites of colorectal surgery (increased by 29.09%),followed by preoperative shower of femoral neck repair surgery (increased by 26.24%),preoperative shower of colorectal surgery(increased by 22.95%),and skin preparation on the day of operation (increased by 20.75%).Incidences of SSI in three types of surgeries were not significantly different before and after intervention(all P >0.05).Conclusion The incidences of SSI are different among different types of surgeries,the compliance to most bundled intervention measures has im-proved to some extent after intervention,but effectiveness of intervention measures needs to be further observed.

Objective To explore the anesthetic effects of repeated administration of propofol combined with vitamin C in mice. Methods Forty mice were subjected to daily intraperitoneal injections of 80 mg/kg propofol (P80 group), 70 mg/kg propofol and 50 mg/kg vitamin C (P70+Vc50 group), 55 mg/kg propofol and 100 mg/kg vitamin C (P55+Vc100 group), or 50 mg/kg propofol and 200 mg/kg vitamin C (P50+Vc200 group) for 6 consecutive days, and the anesthesia induction time and anesthesia duration were recorded. Results Compared with the P80 group, the mice in P55 + Vc100 group and P50 + Vc200 group showed significantly shorter anesthesia duration on the first 3 days (P<0.05). In all the groups, anesthesia duration was significantly shortened in the following days compared with that on day 1 (P<0.01);anesthesia duration was shorter on day 3 than on day 2 in P50+Vc200 group (P<0.01), and was shorter on days 4, 5, and 6 than on day 2 in all the groups (P<0.01). In all the groups, the rate of loss of righting reflex (LORR) decreased gradually with time in a similar pattern. Conclusions Vitamin C can reduce the dose of propofol without obviously affecting the anesthetic effect to reduce the incidence of drug tolerance and potential dose-related side effects of propofol.

Objective To explore the anesthetic effects of repeated administration of propofol combined with vitamin C in mice. Methods Forty mice were subjected to daily intraperitoneal injections of 80 mg/kg propofol (P80 group), 70 mg/kg propofol and 50 mg/kg vitamin C (P70+Vc50 group), 55 mg/kg propofol and 100 mg/kg vitamin C (P55+Vc100 group), or 50 mg/kg propofol and 200 mg/kg vitamin C (P50+Vc200 group) for 6 consecutive days, and the anesthesia induction time and anesthesia duration were recorded. Results Compared with the P80 group, the mice in P55 + Vc100 group and P50 + Vc200 group showed significantly shorter anesthesia duration on the first 3 days (P<0.05). In all the groups, anesthesia duration was significantly shortened in the following days compared with that on day 1 (P<0.01);anesthesia duration was shorter on day 3 than on day 2 in P50+Vc200 group (P<0.01), and was shorter on days 4, 5, and 6 than on day 2 in all the groups (P<0.01). In all the groups, the rate of loss of righting reflex (LORR) decreased gradually with time in a similar pattern. Conclusions Vitamin C can reduce the dose of propofol without obviously affecting the anesthetic effect to reduce the incidence of drug tolerance and potential dose-related side effects of propofol.

OBJECTIVETo investigate the effect of propofol on the expression of thrombospondin-1 (THBS-1) mRNA and protein in purified newborn rat cortical astrocytes in vitro.

METHODSAstrocytes were isolated from newborn rat cortex and grown in culture before exposure to propofol at 3, 10, 30, 100 or 300 µmol/L for 6 h, 12, or 24 h. The mRNA level of THBS-1 was detected by RT-PCR, and the protein level of THBS-1 was detected by immunofluorescence cytochemistry and Western blotting.

RESULTSPropofol exposure caused significantly upregulated THBS-1 level in cultured astrocytes (P<0.05) to a level about 1.3 times higher than that in control cells. The mRNA and protein levels of THBS-1 in cultured rat cortical astrocytes were upregulated by exposures to 10, 30 and 100 µmol/L propofol (P<0.01). High expression of THBS-1 mRNA and protein was detected in the cells with exposures for different durations (P<0.05), especially in the 12 h group (P<0.01).

CONCLUSIONPropofol at clinically relevant concentrations can modulate the level of THBS-1 secreted by astrocytes of rat cerebral cortex in vitro.

Animals ; Astrocytes ; drug effects ; metabolism ; Cells, Cultured ; Cerebral Cortex ; cytology ; Propofol ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Thrombospondin 1 ; metabolism

Objective To investigate the effect of propofol on the expression of thrombospondin-1 (THBS-1) mRNA and protein in purified newborn rat cortical astrocytes in vitro. Methods Astrocytes were isolated from newborn rat cortex and grown in culture before exposure to propofol at 3, 10, 30, 100 or 300μmol/L for 6 h, 12, or 24 h. The mRNA level of THBS-1 was detected by RT-PCR, and the protein level of THBS-1 was detected by immunofluorescence cytochemistry and Western blotting. Results Propofol exposure caused significantly upregulated THBS-1 level in cultured astrocytess (P<0.05) to a level about 1.3 times higher than that in control cells. The mRNA and protein levels of THBS-1 in cultured rat cortical astrocytes were upregulated by exposures to 10, 30 and 100 μmol/L propofol (P<0.01). High expression of THBS-1 mRNA and protein was detected in the cells with exposures for different durations (P<0.05), especially in the 12 h group (P<0.01). Conclusion Propofol at clinically relevant concentrations can modulate the level of THBS-1 secreted by astrocytes of rat cerebral cortex in vitro.