OBJECTIVETo evaluate the effect of microwave sintering on the translucency of zirconia and to compare these effect with those of conventional sintering. The relationship between the microstructure of specimens and translucency was investigated.

METHODSA total of 10 disc-shaped specimens were fabricated from 2 commercial brands of zirconia, namely, Zenostar and Lava. Each group included 5 discs. Conventional sintering was performed according to the manufacturers' specifications. The maximum temperature for Zenostar was 1,490 °C, whereas that for Lava was 1,500 °C. The dwelling time was 2 h. The sintering temperature for microwave sintering was 1,420 °C, heating rate was 15 °C · min⁻¹, and dwelling time was 30 min. After sintering, the translucency parameter (TP) of the specimens were measured with ShadeEye NCC. The sintered density of the specimens was determined by Archimedes' method. The grain size and microstructure of the specimens were investigated by scanning electron microscopy.

RESULTSDensity and translucency slightly increased by microwave sintering, but no significant difference was found between microwave and conventional sintering (P > 0.05). Small and uniform microstructure were obtained from microwave sintering. The mean TP of Lava was significantly higher than that of Zenostar (P < 0.001).

CONCLUSIONThe translucency of zirconia sintered by microwave sintering is similar to that of the zirconia sintered by conventional sintering.

Ceramics ; chemistry ; Dental Prosthesis Design ; methods ; Heating ; Materials Testing ; Microscopy, Electron, Scanning ; Microwaves ; Surface Properties ; Technology, Dental ; methods ; Zirconium ; chemistry

Objective To evaluate the role of extracellular signal-regulated kinase (ERK) signaling pathway in morphine-or sufentanil-induced inhibition of arrhythmia induced by myocardial ischemia-reperfusion (I/R) in rats and the relationship with connexin43 (Cx43).Methods Forty-eight healthy SPF adult male Sprague-Dawley rats,weighing 200-300 g,were randomly divided into 6 groups (n=8 each) using a random number table:sham operation group (group S);I/R group;morphine group (group M);sufentanil group (group Suf);morphine + ERK inhibitor PD98059 group (group MP);sufentanil + PD98059 group (group SP).Myocardial ischemia was induced by 30 min occlusion of the left anterior descending branch of the coronary artery,followed by reperfusion.In M and Suf groups,the animals were subjected to three cycles of 5-minute drug infusion (morphine 0.3 mg/kg and sufentanil 3 μg/kg,respectively) via the femoral vein interspersed with 5-minute drug-free periods starting from the time point immediately before ischemia.PD98059 10 mg/kg was injected intravenously at 10 min before ischemia in MP and SP groups.The development of ventricular arrhythmia was recorded within 30 min of ischemia and 30 min of reperfusion,and the arrhythmia was scored (AS).The animals were then sacrificed at 120 min of reperfusion,and the myocardial specimens were obtained for determination of the expression of total Cx43 (t-Cx43),phosphorylated Cx43 (p-Cx43),and phosphorylated ERK (p-ERK) by Western blot.Results Compared with group S,the AS was significantly increased,and the expression of p-Cx43 was significantly down-regulated in the other groups,and the expression of t-Cx43 and p-ERK was significantly down-regulated in I/R,SP and MP groups (P＜0.05).Compared with group I/R,the AS was significantly decreased,and the expression of t-Cx43,p-Cx43 and p-ERK was significantly up-regulated in M and Suf groups (P ＜ 0.05).Compared with M and Suf groups,the AS was significantly increased,and the expression of t-Cx43 and p-Cx43 was significantly down-regulated in SP and MP groups (P ＜ 0.05).Conclusion The mechanism by which morphine or sufentanil inhibits arrhythmia induced by myocardial I/R is associated with up-regulated expression of myocardial Cx43 after activation of ERK signaling pathway in rats.

Objective To observe the regulatory role of long non-coding RNA HIF1A-AS1 on the autophagy of pancreatic cancer PANC1 cells induced by hypoxia.Methods The pancreatic cancer PANC1 cells were cultured in a three-gas incubator filled with hypoxic gas mixture (94% N2,5% CO2,1% O2) for 3, 6, 12, 24, 36 and 48 h.HIF1A-AS1 overexpression and low expression PANC1 cells were obtained by the infection of recombinant adenovirus carrying HIF1A-AS1 and the transfection of HIF1A-AS1 targeting siRNA by liposome, and routinely cultured PANC1 cells served as control.The expression of HIF1A-AS1 of PANC1 cells was detected by real-time quantitative PCR after being cultured in hypoxia-induced condition for 24 h.The apoptosis rate was detected by flow cytometry.The autophagy related proteins Beclin 1 were detected by western blot.Results The expression of HIF1A-AS1 in hypoxic cells was increased as the hypoxic time increased since 6 h and peaked at 36 h, which was significantly higher than that in control group (P<0.01).HIF1A-AS1 relative expression in HIF1A-AS1 overexpression and low expression PANC1 cells was 4.49±0.53 and 0.49±0.07, which were normalized to that of control group with the relative expression of 1.Control group had lower HIF1A-AS1 expression than HIF1A-AS1 overexpression PANC1 cells but higher HIF1A-AS1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).The cell apoptosis rate of control, HIF1A-AS1 overexpression and low expression PANC1 cells was (8.27±1.28)%, (6.56±1.49)% and (19.9±2.34)% after 24 h hypoxic culture.Control group had higher HIF1A-AS1 expression than HIF1A-AS1 overexpression PANC1 cells but lower HIF1A-AS1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).The expression of Beclin 1 protein was protein 1.05±0.11, 1.29±0.19 and 0.38±0.18, respectively.Control group had lower Beclin 1 expression than HIF1A-AS1 overexpression PANC1 cells but higher Beclin 1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).Conclusions HIF1A-AS1 can promote autophagy of pancreatic cancer PANC1 cells induced by hypoxia and participate in the pathogenesis and metastasis of pancreatic cancer.

OBJECTIVEThis study evaluated the wear of an antagonist and friction and wear properties of dental zirconia ceramic that was subjected to microwave and conventional sintering methods.

METHODSTen specimens were fabricated from Lava brand zirconia and randomly assigned to microwave and conventional sintering groups. A profile tester for surface roughness was used to measure roughness of the specimens. Wear test was performed, and steatite ceramic was used as antagonist. Friction coefficient curves were recorded, and wear volume were calculated. Finally, optical microscope was used to observe the surface morphology of zirconia and steatite ceramics. Field emission scanning electron microscopy was used to observe the microstructure of zirconia.

RESULTSWear volumes of microwave and conventionally sintered zirconia were (6.940±1.382)×10⁻², (7.952±1.815) ×10⁻² mm³, respectively. Moreover, wear volumes of antagonist after sintering by the considered methods were (14.189±4.745)×10⁻², (15.813±3.481)×10⁻² mm³, correspondingly. Statistically significant difference was not observed in the wear resistance of zirconia and wear volume of steatite ceramic upon exposure to two kinds of sintering methods. Optical microscopy showed that ploughed surfaces were apparent in zirconia. The wear surface of steatite ceramic against had craze, accompanied by plough. Scanning electron microscopy showed that zirconia was sintered compactly when subjected to both conventional sintering and microwave methods, whereas grains of zirconia sintered by microwave alone were smaller and more uniform.

CONCLUSIONSTwo kinds of sintering methods are successfully used to produce dental zirconia ceramics with similar friction and wear properties.
.

Ceramics ; Dental Porcelain ; Friction ; Humans ; Magnesium Oxide ; Materials Testing ; Microscopy, Electron, Scanning ; Microwaves ; Silicon Dioxide ; Surface Properties ; Zirconium

Objective To evaluate the changes of adenosine metabolism pathway related molecules and their contribution to inflammatory injury in primary biliary cholangitis (PBC).Methods The consecutive samples of 49 subjects with PBC from The First People's Hospital of Taicang and The Second People's Hospital of Changshu were recruited from October 2016 to October 2017,and 36 healthy controls were involved in this study.The expression of CD39 and CD73 on CD4+T cells and Foxp3 + regulatory T cells were assayed by flow cytometry and the concentration of adenosine triphosphate (ATP) in serum was analyzed by ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS).The correlations between Tregs,ATP and liver function were analyzed,i.e.,alanine aminotransferase (ALT),aspartate aminotransferase (AST),gamma-glutamyltransferase (GGT),alkaline phosphatase (ALP) and Mayo scores.Results In the patients with PBC,low proportions of CD4+CD39+T cells were noted compared with healthy controls [(5.28 ± 1.92) ％ vs (11.0l ± 3.19) ％,t =10.25,P ＜ 0.01].The patients with PBC also had significantly low proportion of CD4+CD25 + Foxp3+ CD39+ T cells compared with healthy controls [(23.75 ± 9.48) ％ vs (54.68 ± 5.18) ％,t =13.79,P ＜0.01].No significant difference of the proportion of CD4+CD73+T or CD4+CD25+ Foxp3+CD39+T cells was found between PBC and control groups (t values were 2.235 and 1.083,P ＞ 0.05).The level of serum ATP was higher in the patients with PBC than that of healthy controls [(200.28 ± 79.41) μg/L vs (89.20 ± 33.76) μg/L,t =8.367,P ＜ 0.01].A significant correlation was demonstrated between the proportion of CD39 + Treg in total Treg cells and the levels of ATP (r =-0.413,P =0.003),GGT (r=-0.378,P=0.007) and Mayo score (r=-0.382,P=0.007).Conclusion The low proportion of CD39+ Treg cells may contribute to the down-regulation of ATP hydrolysis in the patients with PBC.No significant change of CD73 + Treg cells was found in PBC patients.

BACKGROUND: The aim of this study is to investigate the changes of peripheral blood lymphocyte subsets before and after treatment with pembrolizumab for non-small cell lung cancer and its clinical significance. METHODS: A total of 32 patients with non-small cell lung cancer who received pembrolizumab treatment in The Affiliated Hospital of Qingdao University and Weifang People's Hospital of Shandong Province from January 2015 to December 2020 were selected as the observation group, and 30 healthy people during the same period were selected as the control group. Before treatment and in cycles 1, 2 and 4 after treatment, fluid cytometry was used to detect changes in the levels of lymphocyte subsets in the peripheral blood of patients. RESULTS: The CD3⁺, CD4⁺, CD4⁺/CD8⁺ indexes of patients with non-small cell lung cancer before the treatment were significantly lower than those in the control group (P<0.05), and the CD8⁺ level was significantly increased (P<0.05); After 1 cycle of pembrolizumab treatment, there was no significant difference in the changes of lymphocyte subsets compared with before immunotherapy; After 2 cycles of the treatment, the CD3⁺, CD4⁺, CD4⁺/CD8⁺ values were higher than before the treatment (P>0.05), and the CD8⁺ index was slightly lower than before the treatment (P<0.05); After the fourth cycle of treatment, the CD3⁺, CD4⁺, CD4⁺/CD8⁺ values were significantly improved compared to before the treatment (P<0.05), and the CD8⁺ index was significantly lower than before the treatment (P<0.05); In the treatment process of patients with stable disease (SD)/partial response (PR), the CD3⁺, CD4⁺, CD4⁺/CD8⁺ values of the fourth cycles were higher than before the treatment (P<0.05), and the CD8⁺ index was lower than before the treatment (P<0.05); During the treatment of progressive disease (PD) patients, the changes of lymphocyte subsets in the fourth cycles were not significantly different from those before the treatment (P>0.05). At the same time, this article shows through analysis that the expression of programmed cell death ligand 1 (PD-L1) and pathological types have no obvious influence on the effect of immunotherapy. Multi-factor analysis shows that it is more meaningful to observe the changes of CD3⁺, CD4⁺ and CD8⁺ at the same time to predict the effect of immunotherapy. CONCLUSIONS Pembrolizumab can regulate the changes of T lymphocyte subsets in patients with non-small cell lung cancer, improve the immune status of the patients, and there is no obvious adverse reaction. At the same time, monitoring the changes of lymphocyte subsets during treatment can predict the effect of immunotherapy.

Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five children's hospitals were involved in this program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.

OBJECTIVETo understand the distributions of DNA and neutralizing antibodies of human papillomavirus (HPV)16, 18 in 18-45 year-old women.

METHODSTotally, 1494 women were enrolled through multistage random sampling in Funing, Jiangsu province. Cervical exfoliated cells were collected from them for HPV DNA testing, and serum samples were taken from them for the detection of HPV16, 18 neutralizing antibodies by using pseudovirion-based neutralization assay(PBNA).

RESULTSAmong the 1494 women, 28(1.9%) and 188(12.6%) were positive for DNA and neutralizing antibody of HPV16 respectively, and 15(1.0%) and 60(4.0%) were positive for DNA and neutralizing antibody of HPV18, respectively. There were no significant differences in the detection rates of DNA and neutralizing antibody of HPV16, 18 among different age groups. About 16.7% of the women were infected with HPV16, 18, or both.

CONCLUSIONIn Funing county of Jiangsu province, most women aged 18-45 years has no immunity to HPV16 and 18, indicating that they are appropriate targets for HPV 16/18 vaccination.

Adolescent ; Adult ; Antibodies, Neutralizing ; isolation & purification ; Antibodies, Viral ; isolation & purification ; China ; DNA, Viral ; isolation & purification ; Female ; Human papillomavirus 16 ; immunology ; Human papillomavirus 18 ; immunology ; Humans ; Middle Aged ; Papillomavirus Infections ; prevention & control ; Papillomavirus Vaccines ; Young Adult

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.