1.Bactericidal effect of a novel peptide on oral microorganisms
Xiu YING ; Yingming SUN ; Rui TAO ; Mengjie ZHANG ; Xiu JIANG
Journal of Medical Postgraduates 2016;29(4):359-363
Objective Antimicrobial peptides are the focus of recent research in oral microbiology .This study aimed to eval-uate the activity of a novel antimicrobial peptide pm 11 against oral microorganisms and its action mechanisms . Methods We ana-lyzed the effect of pm11 on oral microorganisms and determined its antimicrobial activity in the saliva environment by measuring its min -imal inhibitory concentration (MIC), minimal bactericide concentration (MBC), and bactericidal kinetics.We observed its bacteri-cidal activity on the biofilms of streptococcus mutans by confocal laser scanning microscopy (CLSM) and the structural changes in the bacterial membrane by scanning electron microscopy (SEM). Results The antimicrobial activity of pm11 varied greatly against dif-ferent oral microorganisms , with its MIC values ranging from 2 μg/mL to 256 μg/mL and its MBC values from 2 μg/mL to >256μg/mL.The bactericidal kinetics showed a decreasing survival rate of bacteria with the lengthening of the intervention time .The inhib-itory-zone diameters exhibited no significant indifference between the water solution and the sterile saliva solution .CLSM revealed an increased number of dead bacteria in the pm 11-treated biofilms , while SEM manifested obvious changes in the shape of the bacteria membrane treated with pm11. Conclusion Our findings suggest that pm11 has a broad spectrum of antimicrobial activities on oral mi-croorganisms and a potential value of clinical application .
2.Action mechanisms of acid-resistant Streptococcus sanguis against Streptococcus mutans
Xiu JIANG ; Yingming SUN ; Rui TAO ; Mengjie ZHANG ; Mengyao HOU
Journal of Medical Postgraduates 2017;30(4):371-375
Objective Streptococcus sanguis is a possible candidate bacterium for the caries replacement therapy, which has no advantages in the acidic environment.The aim of the study was to construct acid-resistant strains of Streptococcus sanguis, determine its acid tolerance, and explore the mechanism of its antagonism against Sterptococcus mutans.Methods By gradually reducing the pH value of the medium, we constructed acid-resistant strains of Streptococcus sanguis, observed their growth and measured their acid tolerance according to their survival rate against lethal pH.We evaluated the competitive relationship between Streptococcus sanguis and Streptococcus mutans by plate experiment and detected the changes of related acid resistance genes by real-time quantitative PCR.Results The growth of Streptococcus sanguis and its acid-resistant strains were limited by the pH value, and that of Streptococcus sanguis was better in either acidic or normal environment.The lethal pH value of Streptococcus sanguis was 3.6, that of its acid-resistant strains was 2.3, and the survival rate of the acid-resistant strains was 66.59% in the pH 3.6 environment.In comparison, the lethal pH value of Streptococcus mutans was 2.5, that of its acid-resistant strains was 2.1, and the survival rate of the acid-resistant strains was 2.55% in the pH 2.5 environment.In the presence of chloramphenicol, the acid-resistant strains could not survive in the original lethal pH.In the sub-lethal pH environment, the expressions of the acid resistance-related genes Groel and Dnak in the acid-resistant strains were significantly up-regulated as compared with those in the original Streptococcus sanguis (P<0.05).Conclusion Streptococcus sanguis has an acid adaptability and can enhance acid resistance in the sub-lethal pH environment.Acid-resistant Streptococcus sanguis in the replacement therapy may provide some new ideas for the treatment of dental caries.
3.Subtype distribution and long-term titer fluctuation patterns of serum anti-Epstein-Barr virus antibodies in a non-nasopharyngeal carcinoma population from an endemic area in South China:a cohort study
Du JINLIN ; Chen SUIHONG ; Huang QIHONG ; Xie SHANGHANG ; Ye YANFANG ; Gao RUI ; Guo JIE ; Yang MENGJIE ; Liu QING ; Hong MINGHUANG ; Cao SUMEI
Chinese Journal of Cancer 2016;35(9):447-454
Background: Serum immunoglobulin A antibodies against Epstein–Barr virus (EBV), viral capsid antigen (VCA?IgA) and early antigen (EA?IgA), are used to screen for nasopharyngeal carcinoma (NPC) in endemic areas. However, their routine use has been questioned because of a lack of specificity. This study aimed to determine the distributions of different subtypes of antibody and to illustrate how the natural variation patterns affect the specificity of screening in non?NPC participants. Methods: The distribution of baseline VCA?IgA was analyzed between sexes and across 10?year age groups in 18,286 non?NPC participants using Chi square tests. Fluctuations in the VCA?IgA level were assessed in 1056 non?NPC participants with at least two retests in the first 5?year period (1987–1992) after the initial screening using the Kaplan–Meier method. Results: The titers of VCA?IgA increased with age (P < 0.001). Using a previous serological definition of high NPC risk, nasopharyngeal endoscopy and/or nasopharyngeal biopsy would be recommended in 55.5% of the non?NPC partici?pants with an initial VCA?IgA?positive status and in 20.6% with an initial negative status during the 5?year follow?up. However, seroconversions were common; 85.2% of the participants with a VCA?IgA?positive status at baseline con?verted to negative, and all VCA?IgA?negative participants changed to positive at least once during the 5?year follow?up. The EA?IgA status had a high seroconversion probability (100%) from positive to negative; however, it had a low probability (19.6%) from negative to positive. Conclusions: Age? and sex?specific cutoff titer values for serum anti?EBV antibodies as well as their specific titer fluc?tuation patterns should be considered when defining high NPC risk criteria for follow?up diagnostics and monitoring.
4.Genome-wide molecular characterization of a rare group A rotavirus equine-like DS-1-like G3P 8 in China
Guangping XIONG ; Yuhang WEI ; Rui PENG ; Jiaxin FAN ; Xiaoping TANG ; Zhimiao HUANG ; Mengjie DONG ; Ruyi CHE ; Dandi LI
Chinese Journal of Experimental and Clinical Virology 2024;38(1):29-36
Objective:A genome-wide molecular characterization of FJ21351116, a strain of G3P[8]-E2 2021 collected in Fujian, China, was performed.Methods:Whole genome sequencing of FJ21351116 was performed using a high-sensitivity group A rotavirus whole genome sequencing method. Genomic characteriza-tion of the virus was assessed by nucleic acid sequence analysis using MEGA 11.0, Geneious 9.0.2 and DNASTAR software. Neutralization epitopes of VP7 and VP4 (VP8*) were analyzed using BioEdit v. 7.0.9.0 and PyMOL v. 2.5.2.Results:In this study, FJ21351116 was shown to be a G3-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2 genotype, and the result of phylogenetic tree showed that the VP7, VP4, VP3, and NSP2-NSP5 genes of the FJ21351116 strain were related to the equine-like DS-1-like G3P[8] genes that have been detected in Japan in recent years. VP6, VP1, VP2, and NSP1 genes are closely related to G2P[4] in most countries, especially in Singapore, suggesting that this strain was formed by genetic reassortment during the evolution of equine-like G3P[8] and G2P[4]. Evolutionary relationships between the VP7/VP4 genes of FJ21351116 and Rotarix and RotaTeq vaccines suggest that the multiple mutations in both VP7 and VP4 (VP8*) neutralizing antigenic epitopes and vaccine amino acid sites. It is hypothesized that the Rotarix and RotaTeq vaccines may be less effective against equine DS-1-like G3P[8] RVA, and the sequence differences with Rotarix are higher than those with RotaTeq.Conclusions:In this study, we found a rare case of DS-1-like G3P [8] RVA strain in China. Currently, horse-like DS-1-like G3P [8] RVA is relatively rare in China and may be poorly protected by vaccine strains, emphasizing the importance of continuous monitoring of RVA strains and the development of efficient and full-coverage RVA vaccines.
5.Reimaging biological barriers affecting distribution and extravasation of PEG/peptide- modified liposomes in xenograft SMMC7721 tumor.
Hailing TANG ; Mengjie RUI ; Junhua MAI ; Wei GUO ; Yuhong XU
Acta Pharmaceutica Sinica B 2020;10(3):546-556
Liposomes, as one of the most successful nanotherapeutics, have a major impact on many biomedical areas. In this study, we performed laser scanning confocal microscope (LSCM) and immunohistochemistry (IHC) assays to investigate the intra-tumor transport and antitumor mechanism of GE11 peptide-conjugated active targeting liposomes (GE11-TLs) in SMMC7721 xenograft model. According to classification of individual cell types in high resolution images, biodistribution of macrophages, tumor cells, cells with high epidermal growth factor receptor (EGFR) expression and interstitial matrix in tumor microenvironment, in addition, their impacts on intra-tumor penetration of GE11-TLs were estimated. Type I collagen fibers and macrophage flooded in the whole SMMC7721 tumor xenografts. Tumor angiogenesis was of great heterogeneity from the periphery to the center region. However, the receptor-binding site barriers were supposed to be the leading cause of poor penetration of GE11-TLs. We anticipate these images can give a deep reconsideration for rational design of target nanoparticles for overcoming biological barriers to drug delivery.
6.Report of six cases with mast cell leukemia and a literature review
Feng ZHU ; Yuan YU ; Chunyan CHEN ; Wenbing DUAN ; Qian JIANG ; Rui YAN ; Yu SUN ; Yanqiu HAN ; Jing ZHANG ; Huan WANG ; Qiurong ZHANG ; Suning CHEN ; Wanhui YAN ; Mengjie CAI ; Zhibo ZHANG ; Jia YIN ; Qian WANG
Chinese Journal of Internal Medicine 2024;63(10):996-1000
From October 2021 to February 2023, we retrospectively analyzed the clinical and laboratory data of six patients (three male and three female, median age: 54 years, age range: 29-73 years) with mast cell leukemia (MCL) diagnosed in the First Affiliated Hospital of Soochow University (The Mastocytosis Collaborative Network of China). All patients had acute MCL, with at least one C-finding present. The main clinical presentations were hypoalbuminemia ( n=4), fatigue ( n=3), fever ( n=2), abdominal discomfort ( n=2), osteolytic lesions ( n=2), dizziness ( n=1), skin flushing ( n=1), and weight loss ( n=1). Splenomegaly and lymphadenopathy were noted in six and three patients, respectively. Six patients were strongly positive for CD117, five were positive for CD30 and CD25, and four were positive for CD2. Four patients had a normal karyotype and two patients had an abnormal karyotype. Gene mutations were detected in 4/6 cases. The median serum tryptase level was 24.9 (range: 20.1-171.9) μg/L. Two patients were treated with venetoclax and azacitidine for induction (one patient achieved partial remission by combination with afatinib, while there was no remission after combination with dasatinib in the other patient). Two patients did not achieve complete remission despite treatment with cladribine and imatinib, respectively. One patient treated with interferon combined with glucocorticoids was lost to follow-up, and one patient abandoned treatment. The follow-up time ranged from 1.1 to 21.7 months. Three patients died and two survived. Overall, MCL is a rare subtype of systemic mastocytosis with heterogeneous clinical course, and these patients have poor outcome. A better understanding of the clinical characteristics, treatment, and prognosis of MCL is urgently needed.
7.Effect of Astrocyte-neuron Coupling Imbalance in Development of Alzheimer's Disease and Intervention Mechanism of Kidney-tonifying and Marrow-filling TCM Prescriptions
Guanghui HAN ; Shenghua KANG ; Hongni YU ; Mengjie SUN ; Dongyue LI ; Rui MA ; Weizhe ZHEN ; Tao MA
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(8):1-9
Astrocytes are important nerve cells in the central nervous system (CNS), which mainly play a key role in nutrition and support. Astrocytes and neurons undergo close energy coupling and substance coupling, which are closely related and interact with each other. In recent years, many studies have shown that the astrocyte-neuron coupling imbalance plays a central role in the occurrence and progression of Alzheimer's disease (AD) and serves as an important therapeutic target receiving increasing attention. According to traditional Chinese medicine (TCM) theory, the main pathogenesis of AD is kidney deficiency and marrow inadequacy, and in clinical medication, kidney-tonifying and marrow-filling TCM prescriptions are often employed with satisfactory results achieved. As reported, many kidney-tonifying and marrow-filling prescriptions exhibit regulatory and protective effects on the imbalance of astrocyte-neuron coupling, suggesting that the effect of kidney-tonifying and marrow-filling prescriptions in treating AD may have some internal relationship with its regulation of the imbalance of astrocyte-neuron coupling. This article reviewed the underlying internal relationship between the imbalance of astrocyte-neuron coupling and the pathogenesis of kidney deficiency and marrow inadequacy in AD and the research progress in the intervention mechanism of TCM for tonifying the kidney and filling the marrow.
8.Cost-utility Analysis of Pembrolizumab in the Second-line Treatment of Advanced Hepatocellular Carcinoma Based on Two Models
Rui MENG ; Ting ZHOU ; Fenghao SHI ; Zijing WANG ; Mengjie LUO ; Aixia MA
China Pharmacy 2021;32(22):2761-2766
OBJECTIVE:To evaluate the econo mics of pembrolizumab in the second-line treatment of advanced hepatocellular carcinoma in China. METHODS :From the perspective of Chinese healthcare system ,a three-state PartSA model and Markov model were established ;the cost and utility for the second-line treatment of advanced hepatocellular carcinoma in China were compared between pembrolizumab and placebo. The circulation cycle of the model was 3 weeks and the study time limit was lifetime;one-way sensitivity analysis ,probability sensitivity analysis and scenario analysis were used to verify the robustness of the base-case analysis results. RESULTS :PartSA results showed that the ICER for the second-line treatment of advanced hepato- cellular carcinoma with pembrolizumab was 1 266 846.18 yuan/QALY,which is far more than 1-3 times of China ’s per capita GDP in 2020. The results of one-way sensitivity analysis showed that the three parameters that had the greatest impact on ICER were the PFS status utility of the placebo group ,the PFS status utility of the pembrolizumab group ,and the cost of pembrolizumab. The results of probability sensitivity analysis verified the robustness of the base-case analysis. The scenario analysis showed that the treatment cost of pembrolizumab had dropped significantly when the charity donation of pembrolizumab was considered. Although it was still not economical ,ICER was close to 3 times of per capita GDP of China in 2020. When WTP threshold was 1 and 3 times of China ’s per capita GDP ,the economic prices of pabolizumab (100 mg)were 4 157.67 and 5 829.24 yuan,respectively. The results of Markov model were similar to those of PartSA model. CONCLUSIONS :Under the WTP threshold of 1-3 times China ’s per capita GDP in 2020,pembrolizumab is not economical for second-line treatment of advanced hepatocellular carcinoma.
9.Effect of Toddalia asiatica Alcohol Extract on Apoptosis of Non-small Cell Lung Cancer A549 Cells Based on Autophagy Pathway
Lan HONG ; Hao WU ; Rui TIAN ; Jia FENG ; Ziming HOU ; Mengjie TIAN ; Bonan TAO ; Xi SHEN ; Chunyu CAO ; Lin YUAN
Chinese Journal of Experimental Traditional Medical Formulae 2022;28(20):78-85
ObjectiveTo study the effects of Toddalia asiatica alcohol extract on autophagy and apoptosis of non-small cell lung cancer A549 cells, and to explore its possible mechanism. MethodA549 cells were cultured in vitro. Cell counting kit-8 (CCK-8) was used to detect the proliferation of A549 cells, and cell survival rate was calculated to screen the drug concentration. The apoptosis in each dose group and that after the use of 3-methyladenine (3-MA), an autophagy inhibitor, were detected by flow cytometry combined with Annexin V-FITC/PI double staining. Western blot was used to detect the expression levels of apoptosis-related proteins such as B cell lymphocytoma-2(Bcl-2), Bcl-2-associated X protein(Bax), microtubule-associated protein 1 light chain 3 (LC3), cleaved cysteinyl aspartate-specific protease-3 (cleaved Caspase-3), activated poly (Adenosine diphosphate) ribonucleotide polymerase (cleaved PARP1), PARP1, activated death activator (t-Bid), Bid, and ubiquitin-binding protein p62 in each group and those after the use of 3-MA. ResultCompared with the conditions in the control group, the cell survival rate in 0.25 g·L-1 group (P<0.05), and 0.5, 1, 2, 4 g·L-1 groups (P<0.01) was decreased after 24 h intervention. Additionally, the cell survival rate was reduced in a concentration-dependent manner at 48 h and it was less than 10% at 4 g·L-1 (P<0.01). Compared with the conditions in the control group, the total apoptosis rate in 0.5 g·L-1 group was increased (P<0.05), and the apoptosis rate in 1 and 2 g·L-1 groups was also increased (P<0.01). Compared with the 2 g·L-1 group and 3-MA group, the 3-MA combined with T. asiatica alcohol extract had significantly decreased apoptosis rate (P<0.01). Compared with the conditions in the control group, elevated expression of pro-apoptotic proteins cleaved PARP1, Bax and t-Bid in 1 and 2 g·L-1 groups (P<0.05, P<0.01), and reduced expression of Bid in the 2 g·L-1 group (P<0.01) were found. Compared with the conditions in the control group, the expression of anti-apoptotic protein Bcl-2 (P<0.05, P<0.01) and the level of p62 (P<0.01) were down-regulated in 0.5, 1, 2 g·L-1 groups, while the level of LC3 Ⅱ protein was up-regulated (P<0.01), with certain concentration dependence. ConclusionT. asiatica alcohol extract could significantly inhibit the proliferation of A549 cells, which might be related to promoting autophagy and inducing apoptosis.