1.The effect of wza gene deletion in Klebsiella pneumoniae on capsule formation and bacteriophage sensitivity
Zheng FAN ; Hongbo LIU ; Yuchen CHEN ; Xiaohu CUI ; Zhoufei LI ; Tongtong FU ; Jing YUAN
Chinese Journal of Preventive Medicine 2024;58(7):992-997
Objective:To investigate the effects of wza gene deletion in Klebsiella pneumoniae on capsule formation ability and bacteriophage sensitivity. Methods:The wza deletion mutant strain was constructed through a temperature-sensitive plasmid-mediated homologous recombination. The growth curves of W14 and Δ wza were detected by measuring the optical density OD 600. In order to analyze the effect of gene wza on bacterial capsule formation, wild-type strain W14 and Δ wza mutant strain were detected by transmission electron microscope, and their capsule contents were measured by quantifying the uronic acid contents. The plaque assay was used to detect bacterial sensitivity to bacteriophage in wild-type strain W14 and Δ wza mutant strain. The t test was used to compare whether there were differences in the contents of uronic acid in the capsules of wild-type strain W14 and Δ wza mutant strain. Results:The PCR results revealed that the Δ wza mutant strain was successfully constructed. Compared with wild-type strain W14, the growth curves of Δ wza on the solid plates demonstrated a slightly slower growth. However, no difference in growth was observed among wild-type strain W14 and Δ wza mutant strains in LB broth. The transmission electron microscope results showed that wza gene deletion resulted in the loss of capsule in bacteria. The uronic acid content assay suggested that the capsule content was significantly decreased in Δ wza mutant strain (45.963±2.795) μg/ml compared with wild-type strain W14 (138.800±5.201) μg/ml. There was a statistical difference between the two groups ( t=27.233, P<0.001). The plaque assay indicated that bacteria lost its sensitivity to bacteriophage when gene wza was deleted. Conclusion:Deletion of the wza gene impairs bacterial capsule formation ability and can affect bacterial sensitivity to bacteriophage phiW14.
2.Expression, purification and functional validation of phage depolymerase from hypervirulent Klebsiella pneumoniae serotype K1
Zheng FAN ; Yuchen CHEN ; Hongbo LIU ; Xiaohu CUI ; Zhoufei LI ; Tongtong FU ; Jing YUAN
Chinese Journal of Preventive Medicine 2024;58(9):1348-1353
Objective:To express and purify the phage depolymerase from hypervirulent Klebsiella pneumoniae (hv Kp) serotype K1 and validate its function. Methods:Phage that infected serotype K1-type hv Kp was isolated from hospital sewage. The biology and morphology of the phage were determined by plaque assay and transmission electron microscopy. The whole genome of the phage was sequenced by the Illumina HiSeq 2500 platform. The presence of depolymerase was determined by observing the plaque halo. Bioinformatic analysis and prokaryotic protein expression system were further used to predict and identify phage depolymerase. The depolymerase gene fragment was obtained by PCR and cloned into the pET28a expression vector, and the expression and purification of the depolymerase were completed in strain BL21. The depolymerase activities on the capsular polysaccharide of serotype K1-type hv Kp clinical isolates were detected by plaque assay and low-speed centrifugation assay. Results:A lytic phage (phiA2) that infected serotype K1-type hv Kp clinical isolate was isolated from hospital sewage. It was typical of the Caudovirales order and Autographiviridae family, and its whole genome was 43 526 bp in length and contained 51 coding domain sequences. The phage phiA2-derived depolymerase phiA2-dep was predicted, expressed and purified. The plaque assay and low-speed centrifugation assay indicated that the depolymerase phiA2-dep had good lytic activity on the capsular polysaccharide of serotype K1-type hv Kp clinical isolates. Conclusion:Depolymerase phiA2-dep can specifically degrade the capsular polysaccharide of serotype K1-type hv Kp, which has potential application value in treating bacterial infection.
3.The effect of wza gene deletion in Klebsiella pneumoniae on capsule formation and bacteriophage sensitivity
Zheng FAN ; Hongbo LIU ; Yuchen CHEN ; Xiaohu CUI ; Zhoufei LI ; Tongtong FU ; Jing YUAN
Chinese Journal of Preventive Medicine 2024;58(7):992-997
Objective:To investigate the effects of wza gene deletion in Klebsiella pneumoniae on capsule formation ability and bacteriophage sensitivity. Methods:The wza deletion mutant strain was constructed through a temperature-sensitive plasmid-mediated homologous recombination. The growth curves of W14 and Δ wza were detected by measuring the optical density OD 600. In order to analyze the effect of gene wza on bacterial capsule formation, wild-type strain W14 and Δ wza mutant strain were detected by transmission electron microscope, and their capsule contents were measured by quantifying the uronic acid contents. The plaque assay was used to detect bacterial sensitivity to bacteriophage in wild-type strain W14 and Δ wza mutant strain. The t test was used to compare whether there were differences in the contents of uronic acid in the capsules of wild-type strain W14 and Δ wza mutant strain. Results:The PCR results revealed that the Δ wza mutant strain was successfully constructed. Compared with wild-type strain W14, the growth curves of Δ wza on the solid plates demonstrated a slightly slower growth. However, no difference in growth was observed among wild-type strain W14 and Δ wza mutant strains in LB broth. The transmission electron microscope results showed that wza gene deletion resulted in the loss of capsule in bacteria. The uronic acid content assay suggested that the capsule content was significantly decreased in Δ wza mutant strain (45.963±2.795) μg/ml compared with wild-type strain W14 (138.800±5.201) μg/ml. There was a statistical difference between the two groups ( t=27.233, P<0.001). The plaque assay indicated that bacteria lost its sensitivity to bacteriophage when gene wza was deleted. Conclusion:Deletion of the wza gene impairs bacterial capsule formation ability and can affect bacterial sensitivity to bacteriophage phiW14.
4.Expression, purification and functional validation of phage depolymerase from hypervirulent Klebsiella pneumoniae serotype K1
Zheng FAN ; Yuchen CHEN ; Hongbo LIU ; Xiaohu CUI ; Zhoufei LI ; Tongtong FU ; Jing YUAN
Chinese Journal of Preventive Medicine 2024;58(9):1348-1353
Objective:To express and purify the phage depolymerase from hypervirulent Klebsiella pneumoniae (hv Kp) serotype K1 and validate its function. Methods:Phage that infected serotype K1-type hv Kp was isolated from hospital sewage. The biology and morphology of the phage were determined by plaque assay and transmission electron microscopy. The whole genome of the phage was sequenced by the Illumina HiSeq 2500 platform. The presence of depolymerase was determined by observing the plaque halo. Bioinformatic analysis and prokaryotic protein expression system were further used to predict and identify phage depolymerase. The depolymerase gene fragment was obtained by PCR and cloned into the pET28a expression vector, and the expression and purification of the depolymerase were completed in strain BL21. The depolymerase activities on the capsular polysaccharide of serotype K1-type hv Kp clinical isolates were detected by plaque assay and low-speed centrifugation assay. Results:A lytic phage (phiA2) that infected serotype K1-type hv Kp clinical isolate was isolated from hospital sewage. It was typical of the Caudovirales order and Autographiviridae family, and its whole genome was 43 526 bp in length and contained 51 coding domain sequences. The phage phiA2-derived depolymerase phiA2-dep was predicted, expressed and purified. The plaque assay and low-speed centrifugation assay indicated that the depolymerase phiA2-dep had good lytic activity on the capsular polysaccharide of serotype K1-type hv Kp clinical isolates. Conclusion:Depolymerase phiA2-dep can specifically degrade the capsular polysaccharide of serotype K1-type hv Kp, which has potential application value in treating bacterial infection.
5.Clinical significance of serum asprosin level in patients with early renal damage of essential hypertension
Yong LI ; Yakun SU ; Hongbo ZHANG ; Yuan LI ; Zhanhu LI ; Xiaoju YAN
Tianjin Medical Journal 2024;52(6):609-613
Objective To investigate the clinical significance and serum changes of asprosin(ASP)levels in patients with essential hypertension and early renal damage.Methods According to urinary albumin/creatinine ratio(UACR),160 patients with essential hypertension were divided into the simple hypertension group(78 cases)and the early renal damage group(82 cases).Another 60 healthy subjects were selected as the control group.The differences of serum ASP,interleukin-6(IL-6)and UACR levels were compared between groups.The correlation between ASP and blood pressure,IL-6 and UACR was analyzed.Logistic regression analysis was used to analyze the factors influencing early renal damage in essential hypertension.Receiver operating characteristic(ROC)curve was used to analyze the predictive value of each index for early renal injury.Results The serum levels of ASP,IL-6 and UACR were higher in the early renal damage group than those in the control group and the simple hypertension group(all P<0.05).The serum levels of ASP and IL-6 showed an increasing trend with the increase of blood pressure.ASP was positively correlated with systolic blood pressure(SBP),diastolic blood pressure(DBP)and IL-6 levels in patients with essential hypertension(all P<0.05).Serum ASP was positively correlated with SBP,UACR and IL-6 levels in essential hypertension patients(P<0.05),and serum ASP was positively correlated with UACR and IL-6 levels in the early renal damage group(P<0.05).Logistic regression analysis showed that higher levels of SBP,ASP and IL-6 were independent risk factors for early renal damage.ROC curve showed that ASP had the largest area under the curve(AUC)of 0.972(95%CI:0.950-0.993).The AUC of combined detection of ASP+IL-6+SBP was 0.986(95%CI:0.972-0.999).Conclusion The increased serum ASP level in patients with early renal damage in essential hypertension is a good predictor of early renal damage.The combined detection of ASP+IL-6+SBP is better than single detection.
6.Exploration and enlightenment on strengthening and innovating party building work in public hospi-tals:take Tongjiang county people's hospital as an example
Hongbo WU ; Jun ZHANG ; Yuan YU
Modern Hospital 2024;24(9):1332-1335,1342
Innovation is the driving force behind leading the development of medicine and continuously meeting the health needs of the people.Strengthening and innovating the Party building work in public hospitals is an inevitable requirement for enhancing the comprehensive leadership of the Party,an urgent need for improving the modern hospital management system,and a mission to fulfill the purpose of serving the people.Facing the 14th Five Year Plan and beyond,public hospitals adhere to the guidance of Party building,serve the Healthy China strategy,and provide sustained impetus for the high-quality development of public hospitals.Tongjiang County People's Hospital,based on its own characteristics and needs,has strengthened and inno-vated the hospital's Party building work in a targeted manner,actively consolidated the achievements of Party building work lead-ing the development of the hospital business work,and established a set of county-level hospital Party building work model,provi-ding useful references for promoting the high-quality development of public hospitals.
7.Correlations of pontine biological indicators on fetal brain median sagittal MRI with gestational week
Lingxiu HOU ; Bingguang LIU ; Ying YUAN ; Yimei LIAO ; Qiaozhen ZHU ; Hongbo GUO ; Ying TAN ; Huiying WEN ; Fang YAN ; Shengli LI
Chinese Journal of Medical Imaging Technology 2024;40(1):88-92
Objective To observe the correlations of pontine biological indicators on fetal brain median sagittal MRI with gestational week.Methods Data of head MRI of 226 normal fetuses without obvious abnormalities of central nervous system(normal group)and 17 fetuses with abnormalities(abnormal group)at gestational age of 23 to 38 weeks were retrospectively analyzed.Pontine biological indicators based on median sagittal MRI were obtained,including pons anteroposterior diameter(PAD),total pons area(TPA),pontine basal anteroposterior length(AP),pontine basal cranio-caudal length(CC),basis pontis area(BPA)and pontine angle of midbrain(MAP).According to the gestational week,the fetuses of normal group were divided into 8 subgroups.The distributing ranges of pontine biological indicators at different gestational weeks were analyzed,and the correlations of pontine biological indicators with gestational week in normal group were explored,and the developmental status of fetal pons in abnormal group were assessed.Results In normal group,PAD,TPA,AP,CC and BPA all showed linear positive correlation(r=0.887,0.914,0.787,0.866,0.865,all P<0.001),while MAP was not significantly correlated with gestational week(P>0.05).Among 17 fetuses in abnormal group,abnormal PAD or TPA was found each in 8 fetuses,abnormal AP was observed in 14,abnormal CC was noticed in 3 and abnormal BPA was found in 11 fetuses.Conclusion Fetal pontine biological indicators such as PAD,TPA,AP,CC and BPA on median sagittal MRI were positively correlated with gestational week,hence being able to be used for evaluating fetal pontine development.
8.Progress in preparation and application of biomimetic nano carriers for cell membrane
Yu DAI ; Hongbo WANG ; Kangqing BIAN ; Lingyi GUO ; Yuan YU
Journal of Pharmaceutical Practice 2023;41(3):135-138
Nanocarriers prepared from organic or inorganic materials are widely used in drug targeting system and diagnosis and treatment of disease. However, there are some problems, such as poor targeting, short circulation time in vivo and improvement in the biocompatibility. Biomimetic nanocarriers has carried out research on the issues, which based on different kinds of cell membrane for the nanocarriers modification, endogenous biofilm improving the biocompatibility of carriers in vivo, more accurate targeting, and even producing immunotherapeutic effect. The principle, method, targeting mechanism and therapeutic effect of biomimetic nano carrier technology of cell membrane have been reviewed in this paper, which provide a new direction for the research of new drug delivery system.
9.Efficacy observation of high-dose non-T-cell depleted PBSC used as grafts for haploidentical HSCT with reduced intensity conditioning in elderly patients with AML/MDS
Wenyan MIAO ; Jianli XU ; Hailong YUAN ; Hongbo WANG ; Ying LIU ; Chunxia HAN ; Linglu DING ; Ming JIANG
Journal of Leukemia & Lymphoma 2023;32(11):652-657
Objective:To investigate the clinical efficacy of high-dose non-T-cell depleted peripheral blood stem cells (PBSC) used as grafts in haploidentical hematopoietic stem cell transplantation with reduced intensity conditioning (RIC-haplo-HSCT) in the treatment of elderly patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS).Methods:The clinical data of AML or MDS 28 patients aged ≥50 years who underwent RIC-haplo-HSCT in the First Affiliated Hospital of Xinjiang Medical University from January 2014 to June 2022 were retrospectively analyzed. All patients received high-dose non-T-cell depleted PBSC as grafts. Anti-CD25 monoclonal antibody and glucocorticoid were added as intensive graft-versus-host disease (GVHD) prophylaxis.Results:All patients achieved hematopoietic reconstruction. The accumulative incidence of grade Ⅱ-Ⅳ and Ⅲ-Ⅳ acute GVHD within 100 d was 22.5% (95% CI 5.1%-39.9%) and 8.2% (95% CI 0-19.2%), respectively. The 3-year cumulative incidence of chronic GVHD was 26.8% (95% CI 7.8%-45.8%), and the incidence of extensive chronic GVHD was 5.9% (95% CI 0-17.1%). The median follow-up time was 35.5 (2-83) months. The 3-year cumulative incidence of relapse and non-relapse mortality was 16.7% (95% CI 2.0%-31.9%) and 12.2% (95% CI 0-25.2%), respectively. The 3-year disease-free survival and overall survival rates were 73.3% (95% CI 56.2%-90.4%) and 79.1% (95% CI 62.2%-96.0%), respectively. Conclusions:High-dose non-T-cell depleted PBSC used as grafts for RIC-haplo-HSCT can achieve good clinical efficacy in elderly patients with AML/MDS.
10.Values of sperm nucleoprotein transformation in predicting recurrent abortion
Li DUAN ; Yong CHEN ; Qinghong QIU ; Gang LIU ; Wenhui JIANG ; Hongbo TANG ; Ye YUAN ; Renshan GE ; Erpo TIAN ; Zina WEN
Chinese Journal of Clinical Laboratory Science 2023;41(10):749-752
Objective To investigate the values of nucleoprotein transformation in sperm for predicting recurrent abortion.Methods A total of 521 infertile couples with complete test indicators on fertility were selected from the reproductive medical clinic of our hospital from 2019 to 2022,among which the ages of the male were from 23 to 56 years old.The following factors causing recurrent abortion were excluded,including the age of woman,body mass index,metabolic disease,antiphospholipid syndrome,uterine and accessory abnormalities,history of caesarean section and intrauterine myoma/cervical conectomy,peripheral blood chromosome abnormalities of both the couple,and adverse life history,such as smoking/alcohol abuse.According to the abortion situation,they were divided into the recurrent abortion group(≥two spontaneous abortions),one spontaneous abortion group and no abortion group.Tukey's multiple comparison was performed to compare the differences of nucleoprotein transformation of sperm in each group by using GraphPad6.0 sta-tistical software.The Pearson method was used to analyze the correlation between nucleoprotein transformation and recurrent abortion.The predictive values of nucleoprotein transformation in recurrent abortion were analyzed by the parameters of sensitivity,specificity,positive predictive value,negative predictive value,Youden index and odd ratio.Results The percentages of abnormal nucleoprotein transformation in recurrent abortion group[(33.31±13.83)%]were significantly higher than those in non-abortion group[(26.85± 15.38)%]and the one abortion group[(28.20±12.50)%,P<0.05].Pearson correlation analysis showed that there was a significant positive correlation between abnormal nucleoprotein transformation and recurrent abortion.The sensitivity and specificity of nucleoprote-in transformation for predicting recurrent abortion were 45.24%and 73.64%,respectively.All of the data of positive predictive value(15.70%),negative predictive value(92.53%),Youden index(18.88%)and odd ratio(2.31)of nucleoprotein transformation in predicting recurrent abortion were higher than those of high DNA stainability(10.64%,90.31%,1.05%and 1.11).Conclusion In the spouses of patients with recurrent abortion,the immaturity of sperm nuclear protein is significantly increased and significantly posi-tively correlated with recurrent abortion.The abnormal nucleoprotein transformation of sperm may be the important factor of recurrent a-bortion in males,and it has high predictive value for recurrent spontaneous abortion in clinical practice.

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