BACKGROUND:The micro/nanostructured gradient biomimetic surface of implant materials can simulate the structure of the extracellular environment in human bone tissue,thereby achieving perfect bone integration function.However,further research is needed on the mechanisms by which the surface microstructure of bone implant materials regulates cell function and promotes osteogenesis. OBJECTIVE:To analyze the effect of titanium sheet microstructure surface on osteogenic differentiation of MC3T3-E1 osteoblasts. METHODS:(1)At a constant voltage of 5 V or 20 V,nanotube arrays of different diameters were prepared on the surface of titanium sheets by acid etching and anodic oxidation techniques,and were recorded as group R5 and group R20,respectively.The surface morphology,roughness,and hydrophilicity of pure titanium sheet(without acid etching or anodizing treatment)were measured in group R5 and group R20.(2)MC3T3-E1 osteoblasts of logarithmic growth stage were inoculated on the surface of pure titanium sheets,R5 group and R20 group respectively.After 24 hours of osteogenic induction culture,the expression of mechanical sensitive channel protein 1 was analyzed by RT-PCR and immunofluorescence staining.Osteoblast inducible base with or without the mechanosensitive channel protein 1 activator Yada1 was added,and alkaline phosphatase staining was performed after 7 days of culture.Alizarin red staining was performed after 14 days of culture. RESULTS AND CONCLUSION:(1)The surface of pure titanium sheets was smooth under scanning electron microscope.Relatively uniform and orderly nanotube arrays with average diameters of about 30 nm and 100 nm were observed on the surface of titanium sheets of groups R5 and R20,respectively.The results of scanning electron microscope were further verified by atomic force microscopy.The surface roughness of titanium sheet of group R5 was higher than that of pure titanium(P<0.05),and the water contact angle was lower than that of pure titanium(P<0.05).The surface roughness of titanium sheet in group R20 was higher than that in group R5(P<0.05),and the water contact angle was lower than that in group R5(P<0.05).(2)RT-PCR and immunofluorescence staining showed that the expression of mechanosensitive channel protein 1 in group R5 was higher than that in pure titanium group(P<0.05),and the expression of mechanosensitive channel protein 1 in group R20 was higher than that in group R5(P<0.05).Under the osteogenic induction,compared with the condition without Yada1,there were no significant changes in the activity of alkaline phosphatase and the deposition of calcified nodules in pure titanium group after Yada1 addition,while the activity of alkaline phosphatase and the deposition of calcified nodules in groups R5 and R20 after Yada1 addition were significantly increased(P<0.05).With or without Yada1,the alkaline phosphatase activity and calcified nodule deposition in group R5 were higher than those in pure titanium group(P<0.05),and the alkaline phosphatase activity and calcified nodule deposition in group R20 were higher than those in group R5(P<0.05).(3)The results show that the surface microstructure of titanium sheet can promote the osteogenic differentiation of osteoblast MC3T3-E1 by activating mechanosensitive channel protein 1.

Objective:To investigate the correlation of the emm genotypes and virulence genes with the isolation sites of Group A Streptococcus (GAS). Methods:It was a retrospective study.The specimens were collected from children with impetigo in Beijing Children′s Hospital, Capital Medical University from 2006 to 2008 for GAS isolation and identification.A total of 24 GAS strains were isolated from 16 children with impetigo, among which 7 pairs of strains were isolated from the throat and skin of 7 children, and 1 pair of strains was isolated from the vulva and skin of one child, and the remaining 8 GAS strains were isolated from the skin pus samples of 8 children.Polymerase chain reaction was applied to detect the emm genotypes and 13 virulence genes ( speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa). The correlation of the emm genotypes and virulence genes with the isolation sites of GAS strains was analyzed. Results:In this study, four emm genotypes were detected, including emm1.0 (15/24), emm12.0 (4/24), emm22.0 (2/24) and emm160.0 (1/24), and one subtype emm12.19 (2/24) was detected as well.The carrying rates of 13 virulence genes speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were 58.3%, 100%, 91.7%, 100%, 50.0%, 12.5%, 54.2%, 66.7%, 16.7%, 25.0%, 12.5%, 100% and 91.7%, respectively.All strains carried 5 to 11 virulence genes and they all carried speB, speF and smeZ.There were significant differences in the carrying rate of speA and speJ among the strains with different emm genotypes (all P<0.05). There was no significant difference in the distribution of virulence genes between skin isolates and pharyngeal isolates, including the 5 pairs of strains carrying the emm1.0 genotype (all P>0.05). Conclusions:The distribution of virulence gene of GAS in children with impetigo is significantly correlated with the emm genotype, rather than the isolation site.

Objective:To observe the effects of moxibustion on the levels of glucose-6-phosphate dehydrogenase(G6PD)and reduced nicotinamide adenine dinucleotide phosphate(NADPH)in the plasma and spleen and the CD4+T-cell number in the spleen of rats with adjuvant arthritis,thus to explore the mechanism in rheumatoid arthritis(RA)treatment with moxibustion by regulating the CD4+T-cell proliferation through G6PD-mediated pentose phosphate pathway. Methods:Twenty-seven male Sprague-Dawley rats were randomly divided into a blank group,a model group,and a moxibustion group,with 9 rats in each group.Incomplete Freund's adjuvant was used to induce inflammation in the model group and the moxibustion group.The blank group and the model group were not intervened.In the moxibustion group,suspended moxibustion was performed at bilateral Zusanli(ST36),Guanyuan(CV4),and Ashi points for 30 min,once a day for 24 times in total.Hematoxylin-eosin staining was used to evaluate the histopathological changes of rat synovial tissue;the swelling degree of the rat toes was observed by measuring the toe volume;G6PD and NADPH in the spleen and plasma were detected by Western blotting and enzyme-linked immunosorbent assay.Flow cytometry was used to detect the CD4+T-cell number in the spleen. Results:Compared with the blank group,the levels of G6PD and NADPH in the plasma and spleen and the CD4+T-cell number in the spleen were significantly increased in the model group(P<0.01 or P<0.05).Compared with the model group,the NADPH level in the spleen and plasma and the CD4+T-cell number in the spleen in the moxibustion group decreased significantly(P<0.05 or P<0.01),and the G6PD level in the plasma decreased significantly(P<0.05),but there was no significant difference in the G6PD level in the spleen(P>0.05). Conclusion:Moxibustion can regulate immunity and improve joint synovial inflammation in RA.The mechanism may be that the G6PD-mediated pentose phosphate pathway reduces the production of metabolite NAPDH in CD4+T cells,thereby inhibiting the proliferation of naive CD4+T cells.

Objective: To investigate the effects of herbal cake-partitioned moxibustion on the plasma levels of trimethylamine (TMA), trimethylamine-N-oxide (TMAO), and flavin-containing monooxygenase 3 (FMO3) in rabbits with atherosclerosis (AS), as well as to explore the possible mechanism of herbal cake-partitioned moxibustion in treating AS. Methods: After 1-week adaptive feeding, 28 male New Zealand rabbits were divided into a blank group, a model group, an antibiotic group, and a herbal cake-partitioned moxibustion group according to the random number table method, with 7 rabbits in each group. Rabbits were fed with a basic diet in the blank group, while with a basic diet plus 1％ choline in the remaining groups to prepare the AS model. Rabbits were given drinking water with broad-spectrum antibiotics in the antibiotic group, and herbal cake-partitioned moxibustion in the herbal cake-partitioned moxibustion group for 12 weeks. The atherosclerotic plaques by hematoxylin-eosin (HE) staining, the blood lipid levels, the plasma TMA and TMAO levels by liquid chromatography-mass spectrometry were detected for rabbits in each group at the end of interventions. Liver FMO3 protein expression was detected by Western blotting. Liver FMO3 mRNA expression was detected by real-time fluorescence quantitative polymerase chain reaction. Results: HE staining showed that the arterial wall was rough, the intima was significantly thickened, and more foam cells and lipid deposits were seen in rabbits of the model group. Arterial wall thickening was not obvious with a few foam cells and lipid deposits in the herbal cake-partitioned moxibustion group. Compared with the blank group, the serum levels of low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) were increased (P<0.01), the plasma levels of TMA and TMAO were increased (P<0.05, P<0.01), and the expression levels of liver FMO3 protein and mRNA were all increased (P<0.05, P<0.01); while the serum high-density lipoprotein cholesterol (HDL-C) level was decreased in the model group (P<0.05). Compared with the model group, the LDL-C and TC levels were decreased (P<0.01 or P<0.05), the HDL-C levels were increased (P<0.01), the TMA and TMAO levels were decreased (P<0.05), while the protein and mRNA expression levels of FMO3 were decreased without statistical significance in the herbal cake-partitioned moxibustion group and the antibiotic group. Conclusion: Herbal cake-partitioned moxibustion can slow atherosclerotic plaque formation and regulate lipid levels in AS rabbits, and the mechanism may be related to the down-regulation of TMA and TMAO expression in the plasma.

Objective:To observe clinical phenotypes and analyze the pathogenic genes of Leber congenital amaurosis (LCA).Methods:A retrospective clinical study. From 2019 to 2020, 2 patients diagnosed with LCA by genetic testing in Tianjin Medical University Eye Hospital and their 6 unaffected family members were enrolled in the study. Two patients were from 2 unrelated families, both were probands. The patient's medical history was inquired in detail, slit lamp microscopy, ultra-widefield fundus photography, autofluorescence, and flash visual evoked potential (F-VEP) were performed. Peripheral vein blood (3-5 ml) was collected and genomic DNA was extracted from all study subjects. A total of 381 pathogetic genes associated with inherited retinal diseases, were selected by targeted exome sequencing capture strategy. Sanger sequencing was used to verify suspected pathogenic mutations. Candidate pathogenic mutations were identified after bioinformatics analysis. Sanger sequencing, real-time quantitative polymerase chain reaction and family co-identification were used to confirm the final mutations.Results:Two patients were male, aged 3 and 27 years. One case had vision loss in both eyes, accompanied by nystagmus and acupressure eye sign since childhood. The clinical hallmark of the proband (F1-Ⅱ-3) in F1 includes clearly boundary of optic disc, normal retinal blood vessels and macular fovea. The implied period of the maximum forward wave in both eyes of F-VEP was roughly normal, and its amplitude decreased significantly. The phenotype of the proband (F2-Ⅱ-1) in F2 includes optic nerve head pallor, bone-spicule intraretinal pigmentation, "gold-foil maculopathy" , retina patchy hypo-autofluorescence in both eyes. There was no abnormal phenotype in the eyes of the family members. According to the genetic diagnosis, the proband (F1-Ⅱ-3) carried the GUCY2D gene c.835G>A (p.D279N) (M1) and exon 9-19 deletion (M2) compound heterozygous mutations, in which M1 was derived from healthy mother and M2 was derived from healthy father. The proband (F2-Ⅱ-1) carried CRB1 gene c.1576C>T(R526X) (M3) and c.1522T>C (C508R) (M4) compound heterozygous mutations, in which M3 from the healthy father, M4 from the healthy mother. M2 and M4 were novel mutations. Conclusion:GUCY2D gene mutations lead to LCA1 type in the F1 family, CRB1 gene mutations lead to LCA8 type in the F2 family; there are significant different phenotypes caused by different pathogenic genes.

Group A Streptococcus (GAS) is a very important pathogen, especially for children.On a global scale, GAS is an important cause of morbidity and mortality.But the burden of disease caused by GAS is still unknown in China and also has not obtained enough attention.For this purpose, the expert consensus is comprehensively described in diagnosis, treatment and prevention of GAS diseases in children, covering related aspects of pneumology, infectiology, immunology, microbiology, cardiology, nephrology, critical care medicine and preventive medicine.Accordingly, the consensus document was intended to improve management strategies of GAS disease in Chinese children.

Objective:To compare the efficacy, safety, and influencing factors among children with hepatitis B virus e antigen (HBeAg)-positive chronic hepatitis B (CHB) who received short-term therapy with pegylated interferon alfa-2a (Peg-IFNα-2a) or continuous therapy with entecavir (ETV).Methods:Quantitative data were compared using analysis of variance to compare the differences between groups. Enumeration data were compared by χ2 test (or Fisher's exact test). Univariate and multivariate logistic regressions were used to analyze the influencing factors. Results:Peg-IFNα-2a, ETV, and untreated group had HBsAg clearance rates of 46.2%, 5.3%, and 0 after 52 weeks of therapy, respectively. HBsAg clearance in the patients' group with Peg-IFNα-2a and ETV was all accompanied by anti-HBS positive conversion, and the difference was statistically significant ( χ2=13.616, P=0.001). Peg-IFNα-2a group was followed-up for 104 weeks. Peg-IFNα-2a, ETV, and the untreated group had HBsAg clearance rates of 46.2%, 10.5%, and 0%, respectively, and the differences were statistically significant ( χ2=11.056, P=0.004). Only one of the two children with HBsAg clearance in the ETV group had achieved anti-HBs antibodies, and the difference was statistically significant ( χ2=13.616, P=0.001). Univariate and multivariate logistic regression analysis showed that HBsAg clearance was associated with age and antiviral therapy. During treatment, adverse events such as fever ( n=4, 30.8%), rash ( n=4, 30.8%), fatigue ( n=1, 7.7%), leukopenia ( n=7, 53.8%), arthritis ( n=1, 7.7%), and alopecia ( n=3, 23.1%) were observed in the Peg-IFNα-2a group, while none were observed in the ETV group. Conclusion:Peg-IFNα-2a antiviral therapy produced higher HBsAg clearance than ETV in five-year-old and younger children with HBeAg-positive CHB, while ETV had fewer adverse events and was safer than Peg-IFNα-2a.

Objective:To analyze and summarize the characteristics of liver pathology and their relation to clinical markers and further explore noninvasive markers of liver fibrosis in children with chronic hepatitis B.Methods:Data of 80 hospitalized children with chronic hepatitis B who underwent liver biopsy without antiviral treatment from 2011 to 2020 were retrospectively analyzed. Inflammation and liver fibrosis characteristics were analyzed in children of different ages and genders. Variables with good correlation with liver fibrosis stage were selected to establish a non-invasive diagnostic score of liver fibrosis in children. Measurement data was used to compare the t-test or rank sum test. Mantel-Haenszel χ2 test was used for bidirectional ordered grouping data. Spearman’s rank correlation test was used for rank correlation analysis. Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of the newly established diagnostic score in children with liver fibrosis. Results:The median age of the children was 6.4 years. HBV DNA level was high (P50 = 7.6 log 10 IU/ml), and serum alanine aminotransferase (ALT) in P50 was 171 U/L (< ULN: 5 cases, ULN-2ULN: 10 cases, > 2 ULN: 65 cases). Pathological analysis showed that the incidence of liver tissue inflammation was 97.5%, and the proportion of patients with G≥2 was 42.5%, while S≥2 was 36.3%. The incidence rate of liver fibrosis and liver cirrhosis was 81.3%, and 1.3%, respectively. The changes in liver tissue inflammation and fibrosis were gradually aggravated with the increase of age, and the proportion of high-grade inflammation and liver fibrosis in male children was higher than that in female children. Serum levels of glutamyl transpeptidase (GGT), γ-glutamyltransferase/platelet ratio (GPR) and HBeAg had a good correlation with fibrosis stage ( rs = 0.397, 0.389, and - 0.311) in children with chronic hepatitis B. The combination of GGT, GPR and HBeAg can establish a non-invasive diagnostic score for evaluating liver fibrosis in children. When the score is less than 1.5, it can be diagnosed as S0, and 1.5 ≤ score < 3.5, it can be diagnosed as S1; 3.5 ≤ score < 5.5, the diagnosis of fibrosis is S2; score≥ 5.5, the diagnosis of fibrosis is S≥3. The sensitivity and specificity were 80%, 83%, 86%, and 53%, 55%, 67%, respectively. Conclusion:The incidence of liver tissue inflammation in children with chronic hepatitis B with elevated and fluctuating transaminase levels is high, and the pathological changes of liver tissue aggravate with the age of the children. GGT, GPR and HBeAg have a good correlation with liver fibrosis in children with chronic hepatitis B. Therefore, combining the above-mentioned markers to establish a new noninvasive diagnostic score has certain diagnostic value for liver fibrosis stage S0-S3 in children with chronic hepatitis B.

Objective:To compare the baseline difference in the quantitative hepatitis B core antibody levels (qAnti-HBc) between non-response and response group in children with HBeAg-positive chronic hepatitis B (CHB) who received antiviral therapy, and further explore the proportion and functional activity of CD8 + memory T lymphocyte subsets with different qAnti-HBC levels in peripheral blood of children.Methods:The baseline anti-HBc quantification (qAnti-HBc) levels of 85 children with HBeAg-positive CHB who visited the Department of Infectious Diseases, Children's Hospital of Chongqing Medical University from June 2018 to December 2020 were detected retrospectively. The relationship between the baseline qAnti-HBc level and HBeAg serological response in 37 children who received antiviral therapy was analyzed. The proportion of CD8 + memory T lymphocyte subsets and the secretion levels of interferon (IFN) γ, and tumor necrosis factor (TNF) α in peripheral blood of 59 children at baseline were detected by flow cytometry. The relationship between qAnti-HBc level and the proportion and functional activity of CD8 + memory T lymphocyte subsets was analyzed. Pearson’s Chi-square test was used to compare the count data. Mann-Whitney U test or Kruskal-Wallis test was used to compare measurement data between two or more groups, and Spearman’s rank correlation analysis was used for the correlation between continuous variables. Results:Among 37 children who received entecavir (ETV, 21/37 cases) or pegylated interferon (Peg-IFN, 16/37 cases), 18 cases had developed HBeAg seroconversion (10/ 21 cases in the ETV group, 8/16 cases in the Peg-IFN group). The baseline qAnti-HBc level was significantly higher in the response group [4.71 (4.64~4.81) log 10IU/ml] than the non-response group children [4.54 (4.45~4.64) log 10IU/ml, Z = -3.316, P = 0.001]. The proportion of CD8 + Tem, CD38 +CD8 + Tem, CD38 +CD8 + Temra cells and the levels of IFNγ and TNFα secreted by CD8 + T lymphocytes were significantly higher in the high-qAnti-HBc group than the low-qAnti-HBc group ( P < 0.05). The proportion of CD8 + Tem, CD38 +CD8 + Tem and CD38 +CD8 + Temra cells was significantly higher in ALT > 1× upper limit of normal value (ULN) group than ALT≤1×ULN group ( P < 0.05). However, there were no significant differences in the levels of IFNγ and TNFα secreted by CD8 + T lymphocytes between the two groups ( P > 0.05). Spearman’s correlation analysis showed that qAnti-HBc was positively correlated with the proportion of CD8 + Tem, CD38 +CD8 + Tem, CD38 +CD8 + Temra cells and the level of IFNγ secreted by CD8 +T lymphocytes ( P < 0.05). Additionally, ALT was only positively correlated with the proportion of CD38 +CD8 + TEM and CD38 + CD8 + Temra cells ( P < 0.05). Conclusion:Raised baseline qAnti-HBc level is related to the HBeAg serological response to antiviral therapy in children with CHB. Peripheral blood effector CD8+ T lymphocytes of CHB children with higher qAnti-HBc show stronger phenotype and functional activation characteristics, which may shed some light on the underlying immune mechanism related to antiviral therapy efficacy in children with CHB.

OBJECTIVE：To investigate the effects and its mechanism of pseudostrychnine on the apoptosis of human colon can - cer HT- 29 cells. METHODS ：Human colon cancer HT- 29 cells were randomly divided into blank group ，pseudostrychnine low-dose，medium-dose and high-dose groups （125，250，500 μmol/L）. They were cultured with culture medium without medicine or relevant concentration of pseudostrychnine for 48 h. The cell apoptosis and mitochondrial transmembrane potential were detected by flow cytometry. Western blotting assay was employed to detect the protein expression of P 53，Caspase-3，Caspase-9，DNA re - pair enzyme from rabbit （c-PARP）and Bcl- 2. RESULTS ：Compared with blank group ，apoptotic rate of cells was increased signifi - cantly in pseudostrychnine low-dose ，medium-dose and high-dose groups ，while mitochondrial transmembrane potential was de - creased significantly （P＜0.01），in concentration-dependent manner. The protein expression levels of P 53，Caspase-3，Caspase-9 and c-PARP were increased in pseudostrychnine medium-dose and high-dose groups ，compared with blank group ；while those of Bcl-2 were decreased significantly in pseudostrychnine low-dose ，medium-dose and high-dose groups （P＜0.05 or P＜0.01）. CON - CLUSIONS：Pseudostrychnine may change mitochondrial membrane potential by up-regulating the protein expression of P 53 and down-regulating the protein expression of Bcl- 2，and activate the expression of Caspase- 3，c-PARP and Caspase- 9，so as to acti - vate endogenous mitochondrial pathway and promote the apoptosis of HT- 29 cells.