With use of ~(125)I-udR release test,a significant natural killer activityagainst K_(562) target cells has been determined in human peripheral wholeblood(WB).r There was a gradual decrease in NK activity as rise inthe dilution or WB.In comparison with peripheral monouclear cells(PBMC)oneself,the NK activity lowered distinctly at both 1:4 and 1:8 dilution ofWB(p0.4).It seems that neither the red blood cells nor thePlasma ffeect on NK activity of WB,The NK activity in WB as well as inPBMO was improved by incubation with human leukocyte interferon.TheNK activity of WB and PBMC in patients with hepatocellular carcinomawas signiticantly lower than in normal controls.The results showed tahtNK activity may be determined by using properly diluted WB instead orPBMC,and the assay can be easily performed in clinical practice.

Objective To evaluate the biological effect of endothelin (ET) antagonist on cultured B16 murine melanoma cells. Methods B16 murine melanoma cells were cultured in the presence of various concentrations (31.25, 62.5, 125, 250, 500 μg/mL) of ET antagonist or licoflavone. Then, melanoma cells were harvested for the detection of tyrosinase activity and melanin content. The proliferation rate of melanoma cells was measured with MTT method. The effect of ET antagonist was compared with that of licoflavone. Results Licoflavone had a concentration-dependent inhibition on melanogenesis. The ET antagonist selectively suppressed the ET-induced stimulation of tyrosinase and cell differentiation of B16 cells, but had no direct inhibitory effect on melanogenesis in culture, and little influence on melanocyte viability. The addition of ET antagonist at 200 μg/mL could significantly inhibit ET (0.5 μg/mL)-induced melanogenesis in Bl6 cells. The cytotoxity of the antagonist was relatively lower than that of licoflavone. Conclusions The results suggest that the ET antagonist is a safe skin-whitening ingredient, and may have a wide application perspective in the prevention of endothelin-induced skin pigmentation after UVB irradiation.

Objective To evaluate the safety and efficacy of polymethylmethacrylate/PMMA (Artecoll) as an injectable dermal filler after using laser, radiofrequency and intensive pulse light. Methods In vitro, factional photothermolysis (Affirm) was directly used on the PMMA to see if there was any change in the structure or surface smoothness. In vivo, pig and guinea pig were used as the short-term and long-term models, respectively, for Artecoll. The dermal filler was first injected and then laser treatments conducted.The skin sample was observed through light microscope, scanning electronic microscope and transmission electronic microscope to see whether there were any structural changes, infiltration of inflammatory cells and the regeneration of collagen. Results Through the microscopic observation of in vitro experiment and the animal models, no distortion or rupture of the microsphere were found after the laser treatment. No uneven surface was found in the PMMA microsphere either. The microshpere was surrounded by the inflammatory cells. The infiltration was mild to intermediate with few foreign body giant cells even after several treatments of laser. There was no macrophage seen. But the collagen regeneration was distinguishable after the laser treatment. No obvious structural change was found eventually. Conclusion Artecoll is a safe and effective permanent injectable dermal filler for wrinkle reduction and contour refining.

Objective To investigate the efficacy and safety of photodynamic therapy (PDT) in the treatment of different types of rosacea,and to evaluate its benefit by comparing its efficacy with 10％ sodium sulfacetamide and 5％ sulfur emollient foam.Methods Forty-three subjects with rosacea were enrolled in this study.They were randomized to be treated with PDT (twenty-three subjects) or 10％ sodium sulfacetamide and 5％ sulfur emollient foam (twenty subjects).PDT group subjects received PDT once every seven to ten days for three times while the 10％ sodium sulfacetamide or 5％sulfur emollient foam was applied 2 times per day for thirty days in the other group.Digital photographs were taken before and after one month of treatment in both groups.Blinded independent physicians graded improvement based on these photographs utilizing a percentile evaluation scale.A more than sixty percent remission proved the treatment to be effective.All the complications occurred during the therapy were taken notes and their severity was classified by the subjects.Two dermatology life quality index forms were completed before and after treatment by the subjects to evaluate the change in terms of their quality of life.Results After one month of treatment,PDT proved to be effective on sixty-five percent of subjects (seventy-one percent on papulopustular rosacea and fifty percent on erythematotelangiectatic rosacea).The emollient foam proved to be effective on thirty-five percent of subjects.Statistically significant difference was observed between the overall effective rate of PDT and emollient foam (P＜0.05).In addition,a greater improvement in terms of the quality of life was experienced by the PDT group subjects.No irreversible adverse event was observed in both groups during the study.Conclusions PDT proves to be an effective and safe treatment for rosacea with satisfactory efficacy,significant improvement in patients' quality of life and few irreversible side effects.

Objective To evaluate the clinical efficacy of factional multiplex laser (AffirmTM) with combined apex pulse (CAP) technology in treating depressive acne scars,post inflammatory erythema and enlarged pores and other lesions.By following up,the correlative factors were analyzed to guide the further use of the factional laser (AffirmTM) with CAP technology.Methods Patients who received the AffirmTM laser therapy from Sept.2007 to July 2008 were enrolled in this retrospective follow-up study.Pictures were taken before and after each treatment during the therapy.Then the pictures were evaluated by dermatologists to attain object variables.Other subject variables from patients were recorded during survey.The relation between the efficacy and age,sex and treatment frequencies were analyzed statistically.Results The effective rate was 25.34 ％ for post-acne scars,36.84 ％ for post-acne erythema.28.57 ％ for enlarged pores,and 14.29 ％ for rythids.Nonparametric test showed no statistical difference with gender or age.There was correlation between efficacy and treatment frequencies.No severe adverse effect was observed.Conclusions AffirmTM laser with CAP technology has a good effect on treating post-acne depressed scars and erythema,enlarged pores and fine rythids.

Objective To estimate the influence of ADAR1 gene,which is considered to be responsible for the pathogenesis of dyschromatosis symmetrica hereditaria,on Wnt1 1 expression and tyrosinase activity.Methods Some cultured HaCaT cells were equally divided into four groups:control group remaining untreated,three experimental groups transfected with three different ADAR1-specific shRNAs respectively.Then,Western blot was performed to quantify the expression of Wnt11 protein in HaCaT cells so as to select the most potent shRNA.Some human A375 melanoma cells were cocultured with untransfected HaCaT cells (normally expressing ADAR1 and Wnt1 1 proteins) or HaCaT cells transfected with the selected specific shRNA (lowly expressing ADAR1 and Wnt11 proteins).Thereafter,cell appearance was observed using inverted microscopy at 24,48 and 72 hours,and tyrosinase activity was estimated at 48 hours.Results As Western blot showed,the expression of Wnt 11 protein was significantly lower in the three ADAR1-silenced experimental groups than in the control group.The number of dendritic protrusions at the junction sites between HaCaT cells and A375 cells was significantly decreased,together with a significant reduction in tyrosinase activity (absorbance value:0.0168 ± 0.0069 vs.0.0490 ± 0.0132,P ＜0.01),in A375 cells cocultured with transfected HaCaT cells compared with those cocultured with normal control HaCaT cells.Conclusion ADAR1 gene silencing in HaCaT cells can attenuate the expression of Wnt11 protein,and affect tyrosinase activity in A375 cells.

Unique factors in the space environment can cause dysbiosis of astronauts' gut microbiota and its metabolites, which may exert systematic physiological effects on human body. Recent progress regarding the effect of space flight/simulated space environment (SF/SPE) on the composition of gut microbiota and its metabolites was reviewed in this paper. SF/SPE may cause the increase of invasive pathogenic bacteria and the decrease of beneficial bacteria, aggravating intestinal inflammation and increasing intestinal permeability. SF/SPE may also cause the decrease of beneficial metabolites or the increase of harmful metabolites of gut microbiota, leading to metabolism disorder in vivo, or inducing damage of other systems, thus not beneficial to the health and working efficiency of astronauts. Summarizing the effects of SF/SPE on gut microbiota may provide scientific basis for further researches in this field and the on-orbit health protection of astronauts.
Humans ; Gastrointestinal Microbiome/physiology* ; Dysbiosis/microbiology* ; Bacteria/metabolism*

Objective To analyze the distribution and antimicrobial resistance profile of clinical bacterial strains isolated from blood culture in China.Methods Clinical bacterial strains isolated from blood culture from participating hospitals of Blood Bacterial Resistance Investigation Collaborative System (BRICS) during January 2014 to December 2015 were collected.Antibiotic susceptibility tests were conducted with agar dilution or broth dilution methods as recommended by US Clinical and Laboratory Standards Institute(CLSI)2018.The data were analyzed with Whonet 5.6 software.Results During the study period,4 801 clinical bacterial isolates were collected from 26 hospitals,of which 1 798 (37.5％) were Gram-positive bacteria and 3 003 (62.5％) were gram-negative bacteria.The top 10 isolates were Escherichia coli (33.8％),coagulase-negative Staphylococcus (19.0％),Klebsiella pneumoniae (11.9％),Staphylococcus aureus (10.1％),Acinetobacter baumannii (4.0％),Pseudomonas aeruginosa (3.8％),Streptococcus (3.0％),Enterobacter sulcus (2.9％),Enterococcus faecium (2.8％) and Enterococcus faecalis (1.8％).Methicillin-resistant Staphylococcus aureus (MRSA) and methicillinresistant coagulase-negative Staphylococcus (MRCNS) accounted for 33.9％ (165/487) and 56.9％ (520/913) of Staphylococcus aureus and coagulase-negative Staphylococcus respectively.No vancomycinresistant Staphylococcus was detected.The resistance rate of Enterococcus faecium to vancomycin was 0.7％ (1/135),and no vancomycin-resistant Enterococcus faecaliss was detected.The positive rates of extendedspectrum β-1actamases(ESBLs)-producing Escherichia coli,Klebsiella pneumoniae and Proteus were 56.9％ (923/1 621),30.1％ (172/572) and 29.2％ (7/24),respectively.The positive rates of carbapenemresistant Escherichia coli,Klebsiella pneumoniae,Enterobacter,Salmonella and Citrobacter were 1.2％ (20/1 621),7.2％ (41/572),4.3％ (6/141),1.5％ (1/67) and 2.9％ (1/34),respectively.The resistance rates of Acinetobacter baumannii to polymyxin and tegacycline were 2.6％ (5/190) and 8.9％ (17/190)respectively,and that of Pseudomonas aeruginosa to polymyxin and fosfomycin were 1.1％ (2/183)and 0.6％ (1/183),respectively.Conclusions The surveillance results from 2014 to 2015 show that the main pathogens of blood stream infection in China are Gram-negative bacteria,while Escherichia coli is the most common pathogen,the detection rate of MRSA is lower than other surveillance data in the same period in China;carbapenem-resistant Klebsiella pneumoniae and Escherichia coli are at a low level as shown in this surveillance.

Objective:To investigate the bacterial composition and antimicrobial resistance profile of clinical isolates from bloodstream infections in China.Methods:The clinical bacterial strains isolated from blood culture were collected during January 2020 to December 2020 in member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS). Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute(CLSI, USA). WHONET 5.6 was used to analyze data.Results:During the study period, 10 043 bacterial strains were collected from 54 hospitals, of which 2 664 (26.5%) were Gram-positive bacteria and 7 379 (73.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (38.6%), Klebsiella pneumoniae (18.4%), Staphylococcus aureus (9.9%), coagulase-negative Staphylococci (7.5%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.3%), Enterobacter cloacae (2.8%), Enterococcus faecalis (2.6%), Acinetobacter baumannii (2.4%) and Klebsiella spp (1.8%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 27.6% and 74.4%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci were detected. More than 95% of Staphylococcus aureus were sensitive to rifampicin and SMZco. No vancomycin-resistant Enterococci strains were detected. Extended spectrum β-lactamase (ESBL) producing Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 48.4%, 23.6% and 36.1%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.3% and 16.1%, respectively; 9.6% of carbapenem-resistant Klebsiella pneumoniae strains were resistant to ceftazidime/avibactam combination. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii. The prevalence rate of carbapenem-resistance of Pseudomonas aeruginosa was 23.2%. Conclusions:The surveillance results in 2020 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen, and ESBL-producing strains declined while carbapenem-resistant Klebsiella pneumoniae kept on high level. The proportion and the prevalence of carbapenem-resistant Pseudomonas aeruginosa were on the rise slowly. On the other side, the MRSA incidence got lower in China, while the overall prevalence of vancomycin-resistant Enterococci was low.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2018 to December 2019. Antibiotic susceptibility tests were conducted with agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 14 778 bacterial strains were collected from 50 hospitals, of which 4 117 (27.9%) were Gram-positive bacteria and 10 661(72.1%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.2%), Klebsiella pneumoniae (17.0%), Staphylococcus aureus (9.7%), coagulase-negative Staphylococci (8.7%), Pseudomonas aeruginosa (3.7%), Enterococcus faecium (3.4%), Acinetobacter baumannii(3.4%), Enterobacter cloacae (2.9%), Streptococci(2.8%) and Enterococcus faecalis (2.3%). The the prevalence of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus were 27.4% (394/1 438) and 70.4% (905/1 285), respectively. No glycopeptide-resistant Staphylococcus was detected. More than 95% of S. aureus were sensitive to amikacin, rifampicin and SMZco. The resistance rate of E. faecium to vancomycin was 0.4% (2/504), and no vancomycin-resistant E. faecalis was detected. The ESBLs-producing rates in no carbapenem-resistance E. coli, carbapenem sensitive K. pneumoniae and Proteus were 50.4% (2 731/5 415), 24.6% (493/2001) and 35.2% (31/88), respectively. The prevalence of carbapenem-resistance in E. coli and K. pneumoniae were 1.5% (85/5 500), 20.6% (518/2 519), respectively. 8.3% (27/325) of carbapenem-resistance K. pneumoniae was resistant to ceftazidime/avibactam combination. The resistance rates of A. baumannii to polymyxin and tigecycline were 2.8% (14/501) and 3.4% (17/501) respectively, and that of P. aeruginosa to carbapenem were 18.9% (103/546). Conclusions:The surveillance results from 2018 to 2019 showed that the main pathogens of bloodstream infection in China were gram-negative bacteria, while E. coli was the most common pathogen, and ESBLs-producing strains were in majority; the MRSA incidence is getting lower in China; carbapenem-resistant E. coli keeps at a low level, while carbapenem-resistant K. pneumoniae is on the rise obviously.