1.Establishment of Real-Time PCR and Molecular Beacon Detection Method for Bifidobacteria
Microbiology 1992;0(06):-
0.97).The method of Real-time PCR and molecular beacon detection for bifodobacteria has many advantages,such as being sensitive,specific,simple and fast,and this method can be used in situ detection of bifidobacteria quantitatively.
2.Inhibition of myocardial ischemia/reperfusion injury by exosomes secreted from mesenchymal stem cells
Heng ZHANG ; Meng XIANG ; Dan MENG ; Ning SUN ; Sifeng CHEN
Chinese Journal of Pathophysiology 2016;32(8):1530-1530
Exosomes secreted by mesenchymal stem cells have shown great therapeutic potential in regenerative medicine .In this study, we performed meta-analysis to assess the clinical effectiveness of using exosomes in ischemia /reperfusion injury based on the reports pub-lished between January 2000 and September 2015 and indexed in the PubMed and Web of Science databases .The effect of exosomes on heart function was evaluated according to the following parameters:the area at risk as a percentage of the left ventricle , infarct size as a percentage of the area at risk , infarct size as a percentage of the left ventricle , left ventricular ejection fraction , left ventricular frac-tion shortening , end-diastolic volume , and end-systolic volume .Our analysis indicated that the currently available evidence confirmed the therapeutic potential of mesenchymal stem cell-secreted exosomes in the improvement of heart function .However , further mechanis-tic studies, therapeutic safety and clinical trials are required for optimization and validation of this approach to cardiac regeneration after ischemia/reperfusion injury .
4.Distribution and Antibiotic Resistance of Pathogens from Urinary Tract Infection among Stroke Inpatients for Rehabilitation
Xiangbo MENG ; Yuanbiao LIU ; Lina CHEN ; Xiang FANG
Chinese Journal of Rehabilitation Theory and Practice 2011;17(10):993-996
Objective To investigate the bacterial distribution and antibiotic resistance situation of urinary tract infection (UTI) among the inpatients following stroke. Methods The clinical data of pathogens from UTI in the stroke patients in our hospital from March 2009 to March 2011 were collected and analyzed with WHONET software. Results Among 203 strains from UTI, the most common pathogens were Escherichia coli (35.5%), Enterococcus (27.1%), Klebsiella (8.9%) and Fungi (10.8%). The main Gram negative bacilli were found highly resistant to ampicillin, levofloxacin and cefotaxim. 38.9% of Escherichia coli and 44.4% of Klebsiella produced extended-spectrum β-lactamases (ESBLs) respectively. The rate of antibiotic resistance of Enterococcus was high to the most of antibiotics commonly used. The fungi were highly sensitive to the drugs. Conclusion Gram negative bacilli are the main pathogens of urinary tract infection in stroke inpatients. Drug resistant strains, especially those with severe multiple resistance, increase fast.
5.Clinical significance of MN mRNA expression in peripheral blood of renal cell carcinoma patients
Meng XIANG ; Guolan DUAN ; Yirong CHEN ; Al ET
Chinese Journal of Urology 2001;0(03):-
Objective To study the expression of MN mRNA in peripheral blood of renal cell carcinoma(RCC) patients and to evaluate its clinical significance. Methods Peripheral blood MN mRNA expression was detected by means of RT PCR 30 patients with renal cell carcinoma,including 16 with localized RCC and 14 with metastatic RCC,in 30 patients without renal tumors series as controts. Results With RT PCR, MN mRNA expressin was detected in 13 of 30 cases of RCC (43%) including 5 of 16 patients(31%) with localized RCC and 8 of 14 patients(57%) with metastatic RCC, none of the 30 control cases being positive. No correlation was noted between MN results and tumor stage. Conclusions RT PCR assay of MN is a highly sensitive technique for detecting circulating renal carcinoma cells in the peripheral blood, and it may be helpful in the diagnosis of micrometastasis.MN can be regarded as a cell specific relative protein of clear cell renal carcinoma.
6.Purification and Biological Characteristics of Bacteriocin-like Substance Produced by Lactobacillus buchneri KLDS1.0364
Han-Sheng GONG ; Xiang-Chen MENG ; Hong-Juan LIU ;
Microbiology 1992;0(02):-
The purpose of this study is to obtain effective and stable bacteriocin-like substance from lactic acid bacteria. Lactobacillus buchneri KLDS1.0364,which was isolated from fermented cream,a traditional dairy product in Inner Mongolia,could produce bacteriocin-like substance. The bacteriocin-like substance produced by KLDS1.0364 was partially purified and the characteristics were studied. The bacteriocin-like substance was purified by SP-Sepharose fast flow cation exchange chromatography. The molecular weight of the bacteriocin-like substance was 21.6kD,as determined by tricine-SDS-PAGE. The bacteriocin-like substance remained stable after 30 min at 121℃ and after 2 h of incubation during pH 2~10. Complete inactivation of antimicrobial activity was observed after treatment of the bacteriocin-like substance with several proteinases. Treatment with catalase and ?-amylase did not result in any changes of antimicrobial activity. The mode of action of the bacteriocin-like substance is bactericidal. It exhibited a broad spectrum of antagonistic activity against various species of Gram-positive bacteria,Gram-negative bacteria and fungi.
7.Proteomic identification of proteins in exosomes of patients with atherosclerosis
Mei JIANG ; Jing QUAN ; Heng ZHANG ; Qianqian DING ; Meng XIANG ; Dan MENG ; Ning SUN ; Sifeng CHEN
Chinese Journal of Pathophysiology 2016;32(8):1525-1526
AIM:Atherosclerosis primarily involved systemic arteries .Luminal surface , a monolayer of endothelial cells , of artery directly exposes to blood and is susceptible to active substances in the blood .Exosomes contain significantly amount of proteins and RNAs .Ex-osomes can be good and bad for cells , depending on their component .Thus, exosomes may contribute to atherosclerosis by affecting endothelial cells .This study analyzed the relationship of exosome proteins and atherosclerosis .METHODS: Fifty-six patients and healthy subjects were recruited and divided into two comparisons:healthy subjects vs atherosclerosis ( HS vs AS) , and hypertension vs hypertension plus atherosclerosis ( HT vs HT+AS) .Serum exosomes were decoded by protein mass spectrometry .The protein profile and function were analyzed by gene ontology ( GO) .RESULTS:It was found that five child terms repeatedly appeared in “response to stimulus” and “immune system process” of BP of the two categories ( HS vs AS and AS vs HT+AS):“positive regulation of innate immune response”,“immune response-activating signal transduction”,”activation of innate immune response”,“innate immune re-sponse-activating signal transduction” and “innate immune response activating cell surface receptor signaling pathway ”.Two child terms repeatedly showed in “binding” of MF of the two categories:“antigen binding” and “enzyme binding”.Two proteins, PSMA6 and PSMA7, were repeatedly shown in the two categories .CONCLUSION:GO analysis was utilized for structure hierarchy “tree” to illustrate these proteins involved in various terms in BP , CC and MF.The PPI analysis supplied proteins which may play potentially im-portant roles in AS process .Innate immune system and blood coagulation pathway contribute to AS formation .The proteins, PSMA6, PSMA7 and Annexin A2, may can be the new target proteins for prevention and treatment of AS .
8.Proteomic identification of differentially expressed proteins in blood exosomes of patients with hypertension
Jing QUAN ; Mei JIANG ; Heng ZHANG ; Qianqian DING ; Meng XIANG ; Dan MENG ; Ning SUN ; Sifeng CHEN
Chinese Journal of Pathophysiology 2016;32(8):1525-1525
AIM:To analyze the proteins included in exosomes derived from blood of patients with hypertension and seek the main pathologi -cal changes in hypertension .METHODS:Forty-seven patients and healthy subjects were recruited and divided into two comparisons :healthy subjects vs atherosclerosis ( HS vs AS) , and atherosclerosis vs hypertension plus atherosclerosis ( AS vs HT+AS) .We extrac-ted exosomes from blood and utilized LC-MS/MS to identify the protein expression .We used GO analysis to established the hierarchy programs of biological process and molecular function .PPI was used to find the proteins related to the terms .RESULTS:It was found that three final child terms repeatedly shown in BP of the two categories ( HS vs AS and AS vs HT+AS):“signal transduction in re-sponse to DNA damage”,“response to zinc ion”, and“platelet aggregation”.It was found that two final child terms in MF of the two categories:“interleukin 2 receptor binding” and“ploy(A) RNA binding”.The proteins, PSMA6, PSMA7 and CA2, were related to the terms in the two categories .CONCLUSION: We discovered that the exosome proteins may indicate the pathological changes in hypertension through the biological processes related with the specific proteins .These specific proteins, such as VCL, PSMA6, DP, AKAP, ATP5B and CA2, can be the new indicators for severity of hypertension and new therapeutic targets .
9.Changes of retinal microvasculature and visual acuity prognostic of aflibercept treatment in macular edema secondary to retinal vein occlusion
Guannan WU ; Xiaotian ZHANG ; Guanghui HE ; Meng DONG ; Xiang GAO ; Meng WANG ; Song CHEN
Chinese Journal of Ocular Fundus Diseases 2021;37(4):290-297
Objective:To observe the changes of macular microvessels in patients with retinal vein occlusion (RVO) and macular edema (ME) after intravitreal injection of aflibercept (IVA), and analyze its correlation with best corrected visual acuity (BCVA).Methods:A retrospective case study. Thirty patients (30 eyes) with monocular RVO with ME (RVO-ME) who were diagnosed in the clinical examination of Tianjin Eye Hospital from April 2019 to February 2020 were included in the study. Among them, there were 12 males (12 eyes) and 18 females(18 eyes); the average age was 54.30±13.17 years. The average course of disease was3.43±1.97 months. Both eyes were examined by BCVA and optical coherence tomography (OCTA). The on-demand injection was adopted after the first injection in IVA treatment regimen. The macular area 6 mm×6 mm in both eyes was scanned with an OCTA instrument, and the area of the foveal avascular area (FAZ), FAZ circumference (PERIM), and out-of-roundness were measured at baseline and 1, 3, and 6 months after treatment. Index (AI), blood flow density within 300 μm width of FAZ (FD-300), foveal retinal thickness (CMT), superficial retinal capillary plexus (SCP), deep retinal capillary plexus (DCP) blood flow density. The paired t test was used to compare the quantitative parameters of the affected eye and the contralateral healthy eye at baseline; the changes of the quantitative parameters at baseline and 1, 3, and 6 months after treatment were analyzed by repeated measures analysis of variance. Pearson correlation analysis was used to analyze the correlation between BCVA, retinal perfusion, and macular blood supply parameters at 6 months after IVA treatment. Results:At baseline, compared with the contralateral healthy eye, the FAZ area ( t=-4.091), PERIM ( t=-5.098) and AI ( t=-9.093) of the RVO-ME eye were enlarged, and FD-300 ( t=7.237) and overall SCP and DCP blood flow density ( t=8.735, 9.897) decreased, the difference was statistically significant ( P<0.001). Six months after treatment, the BCVA of RVO-ME eyes was significantly increased, CMT decreased, FAZ area expanded, and AI decreased ( t=8.566, 16.739, -6.469, 9.719; P<0.001), the difference was statistically significant. There was no significant change in the blood flow density of FD-300 and overall SCP and DCP, and the difference was not statistically significant ( t=1.017, 1.197, 0.987; P>0.05). Compared with baseline, the FAZ area of RVO-ME eyes gradually expanded at 3 and 6 months after treatment, and the difference was statistically significant ( F=21.979, P<0.001). Correlation analysis results showed that BCVA at 6 months after treatment was positively correlated with the overall SCP and DCP blood flow density at baseline and 6 months after treatment ( r=-0.538, -0.484, -0.879, -0.854; P<0.05). There was a negative correlation with the area of FAZ 6 months after treatment ( r=0.544, P=0.001). The number of ME recurrences was negatively correlated with BCVA and overall SCP and DCP blood flow density 6 months after treatment ( r=0.604, -0.462, -0.528; P<0.05), it was positively correlated with FAZ area ( r=0.379, P=0.043). Conclusion:Within 6 months of IVA treatment in RVO-ME eyes, ME is significantly reduced and visual acuity is improved; SCP blood flow density decreases, and FAZ area expands.
10.Protective effects of human induced pluripotent stem cell-derived exosomes on high glucose-induced injury in human endothelial cells
Qianqian DING ; Ruiting SUN ; Pingping WANG ; Heng ZHANG ; Meng XIANG ; Dan MENG ; Ning SUN ; Fengyuan CHEN ; Sifeng CHEN
Chinese Journal of Pathophysiology 2016;32(8):1530-1531,1532
AIM:To investigate the effects of human induced pluripotent stem cell-derived exosomes (hiPSC-exo) on cell viability, capillary-like structure formation , and senescence in endothelial cells exposed to high glucose .METHODS: Exosomes were isolated from the conditional medium of hiPSCs and confirmed by transmission electron microscopy , nanoparticle tracking analysis , and Western blot analysis using Alix and CD63 as markers.hiPSC-exo were labeled with PKH26 for tracking.Cultured HUVECs were treated with high glucose (33 mmol/L) with or without hiPSC-exo (20 mg/L) for 48 h, and cell viability, capillary tube formation, and senescence were assessed .RESULTS:hiPSC-exo showed a typical cup shape and could be taken up by human umbilical vascular endothelial cells (HUVECs) in a concentration-dependent manner.When exposed to high glucose, viability and tube formation in HUVECs was signifi-cantly reduced, whereas the proportion of senescent cells was higher compared to that in control HUVECs (P<0.01).Furthermore, hiPSC-exo restored cell viability and capillary-like structure formation , and reduced senescence in HUVECs exposed to high glucose (P<0.01).However, hiPSC-exo had minimal effects on normal HUVECs.Therefore, stem cell-derived exosomes can promote cell proliferation, enhance capillary-like structure formation , and reduce senescence in endothelial cells exposed to high glucose . CONCLUSION:Our study highlights the role of exosomes derived from hiPSC and may provide a new strategy for maintaining vascular health, preventing vascular aging , and avoiding pathological vascular remodeling that occurs in many diseases .