Isolation of Probiotic Piliated Lactobacillus rhamnosus Strains from Human Fecal Microbiota Using SpaA Antiserum-Based Colony Immunoblotting

( Zhen-quan Yang ),( Yu Xue ),( Sheng-qi Rao ),( Mi Zhang ),( Lu Gao ),( Yong-qi Yin ),( Da-wei Chen ),( Xiao-hui Zhou ),( Xin-an Jiao ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 Journal of microbiology and biotechnology Vol.27 No.11

Piliated Lactobacillus rhamnosus (pLR) strains possess higher adherent capacity than non-piliated strains. The objective of this study was to isolate and characterize probiotic pLR strains in human fecal samples. To this end, mouse polyclonal antiserum (anti-SpaA) against the recombinant pilus protein (SpaA) of L. rhamnosus strain GG (LGG) was prepared and tested for its reactivity and specificity. With the anti-SpaA, a method combining the de Man, Rogosa, and Sharpe (MRS) agar plating separation and colony immunoblotting (CIB) was developed to isolate pLR from 124 human fecal samples. The genetic and phenotypic characteristics of the resultant pLR isolates were compared by randomly amplified polymorphic DNA (RAPD) fingerprinting, and examination of adhesion to Caco-2 cells, hydrophobicity, autoaggregation, and in vitro gastrointestinal tolerance. Anti-SpaA specifically reacted with three pLR strains of 25 test strains, as assessed by western blotting, immunofluorescence flow cytometry, and immunoelectron microscopy (IEM) assays. The optimized MRS agar separation plus anti- SpaA-based CIB procedure could quantitatively detect 2.5 × 10³ CFU/ml of pLR colonies spiked in 10⁶ CFU/ml of background bacteria. Eight pLR strains were identified in 124 human fecal samples, and were confirmed by 16S RNA gene sequencing and IEM identification. RAPD fingerprinting of the pLR strains revealed seven different patterns, of which only two isolates from infants showed the same RAPD profiles with LGG. Strain PLR06 was obtained with high adhesion and autoaggregation activities, hydrophobicity, and gastrointestinal tolerance. Anti-SpaA-based CIB is a rapid and inexpensive method for the preliminary screening of novel adherent L. rhamnosus strains for commercial purposes.

Microstructure, Anisotropic Mechanical Properties and Very High Cycle Fatigue Behavior of Ti6Al4V Produced by Selective Electron Beam Melting

Zhongqiang Liu,Zhen Wang,Chaofeng Gao,Ruiping Liu,Zhiyu Xiao 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

In this paper, surface roughness, microstructure, mechanical properties, and very high cycle fatigue behavior of Ti6Al4Vfabricated by selective electron beam melting were studied. Results show that the mechanical properties in xoz direction(yield strength: 891 ± 14 MPa, ultimate tensile strength: 987 ± 8 MPa, elongation: 15.7 ± 1.9%) are better than that in xoydirection (yield strength: 869 ± 11 MPa, ultimate tensile strength: 955 ± 7 MPa, elongation: 9.8 ± 2.3%) due to the presenceof continuous columnar prior-β grain boundary (α layer) and the strong ⟨0001⟩ texture along the building direction. Thevery high cycle fatigue (105–109 cycles) experiments show that when the fatigue life exceeds 107cycles, the sample willstill undergo fatigue fracture. The S–N curve is a bilinear relation, which is caused by the crack initiation position convertedfrom the surface to the interior.

Influence of Majorana doublet on transport through a quantum dot system with ferromagnetic leads

Wei-Jiang Gong,Zhen Gao,Xiao-Qi Wang 한국물리학회 2015 Current Applied Physics Vol.15 No.10

We investigate the electron transport through a quantum dot connected with two ferromagnetic leads, by coupling one Majorana doublet laterally to the quantum dot. It is found that Majorana doublet keeps the value of zero-bias conductance to be independent of the shift of structural parameters, including dot level, relative lead-magnetization direction, and magnetic field on the dot. Even in the cases of asymmetric dot-lead couplings, the zero-bias conductance is weakly dependent on the relative leadmagnetization direction. On the other hand, when Majorana doublet is replaced by Majorana singlet, the zero-bias conductance value becomes sensitive to the structural parameters. Via analyzing the respective particle motion processes, the different influences of Majorana doublet and singlet are explained. We believe that this work can be helpful for understanding the peculiar properties of Majorana doublet.

Alternative Biological Material for Tissue Engineering of the Vagina: Porcine-Derived Acellular Vaginal Matrix

Tian Yanpeng,Liu Yibin,Xiao Yanlai,Li Zhongkang,Zhang Mingle,Chen Liang,Li Zhen,Zhang Wangchao,Zhang Zhiqiang,Kong Desheng,Meng Li,Du Yanfang,Zhang Jingkun,Gao Jingui,Huang Xianghua 한국조직공학과 재생의학회 2024 조직공학과 재생의학 Vol.21 No.2

Background: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a severe congenital disorder characterized by vaginal hypoplasia caused by dysplasia of the Müllerian duct. Patients with MRKH syndrome often require nonsurgical or surgical treatment to achieve satisfactory vaginal length and sexual outcomes. The extracellular matrix has been successfully used for vaginal reconstruction. Methods: In this study, we developed a new biological material derived from porcine vagina (acellular vaginal matrix, AVM) to reconstruct the vagina in Bama miniature pigs. The histological characteristics and efficacy of acellularization of AVM were evaluated, and AVM was subsequently transplanted into Bama miniature pigs to reconstruct the vaginas. Results: Macroscopic analysis showed that the neovaginas functioned well in all Bama miniature pigs with AVM implants. Histological analysis and electrophysiological evidence indicated that morphological and functional recovery was restored in normal vaginal tissues. Scanning electron microscopy showed that the neovaginas had mucosal folds characteristics of normal vagina. No significant differences were observed in the expression of CK14, HSP47, and α-actin between the neovaginas and normal vaginal tissues. However, the expression of estrogen receptor (ER) was significantly lower in the neovaginas than in normal vaginal tissues. In addition, AVM promoted the expression of β-catenin, c-Myc, and cyclin D1. These results suggest that AVM might promotes vaginal regeneration by activating the β-catenin/c-Myc/cyclin D1 pathway. Conclusion: This study reveals that porcine-derived AVM has potential application for vaginal regeneration. Background: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a severe congenital disorder characterized by vaginal hypoplasia caused by dysplasia of the Müllerian duct. Patients with MRKH syndrome often require nonsurgical or surgical treatment to achieve satisfactory vaginal length and sexual outcomes. The extracellular matrix has been successfully used for vaginal reconstruction. Methods: In this study, we developed a new biological material derived from porcine vagina (acellular vaginal matrix, AVM) to reconstruct the vagina in Bama miniature pigs. The histological characteristics and efficacy of acellularization of AVM were evaluated, and AVM was subsequently transplanted into Bama miniature pigs to reconstruct the vaginas. Results: Macroscopic analysis showed that the neovaginas functioned well in all Bama miniature pigs with AVM implants. Histological analysis and electrophysiological evidence indicated that morphological and functional recovery was restored in normal vaginal tissues. Scanning electron microscopy showed that the neovaginas had mucosal folds characteristics of normal vagina. No significant differences were observed in the expression of CK14, HSP47, and α-actin between the neovaginas and normal vaginal tissues. However, the expression of estrogen receptor (ER) was significantly lower in the neovaginas than in normal vaginal tissues. In addition, AVM promoted the expression of β-catenin, c-Myc, and cyclin D1. These results suggest that AVM might promotes vaginal regeneration by activating the β-catenin/c-Myc/cyclin D1 pathway. Conclusion: This study reveals that porcine-derived AVM has potential application for vaginal regeneration.

Cryptotanshinone Induces Inhibition of Breast Tumor Growth by Cytotoxic CD4+ T Cells through the JAK2/STAT4/ Perforin Pathway

Zhou, Jun,Xu, Xiao-Zhen,Hu, Yao-Ren,Hu, Ai-Rong,Zhu, Cheng-Liang,Gao, Guo-Sheng Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-${\gamma}$ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-${\gamma}$ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

Cryptotanshinone and wogonin up-regulate eNOS in vascular endothelial cells via ERa and down-regulate iNOS in LPS stimulated vascular smooth muscle cells via ERb

Barnabas Oche,Lu Chen,Ya-ke Ma,Yue Yang,Chun-xiao Li,Xiao Geng,Li-zhen Qiu,Xiu-mei Gao,Hong Wang 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.2

Phytoestrogens were widely used as natural alternatives to estrogen for treating cardiovascular diseases. They have been reported to have cardioprotective and antiinflammatory response, but the mechanisms remain unclear. In this study, we found cryptotanshinone and wogonin exhibited phytoestrogenic property in an estrogen- responsive reporter assay. In EA.hy926 cells, treatment of cryptotanshinone and wogonin led to significant increase in NO production levels, which were inhibited by co-incubation of estrogen receptor (ER)a antagonist methyl-piperidino-pyrazole (MPP). The expression of endothelial NO synthase (eNOS) and ERa were up-regulated with the same treatment, indicating they stimulate NO and eNOS expression via ERa-dependent pathway in endothelial cells. While in lipopolysaccharide activated vascular smooth muscle cell line A7r5, cryptotanshinone and wogonin exerted anti-inflammatory effects by inhibiting NO and inducible NO synthase expression via ERbdependent pathway. The reduction of NO synthesis was not affected by MPP, and was abrogated by ERb antagonist R,R-tetrahydrochrysene. Our findings provide the potential molecular mechanism of cryptotanshinone and wogonin as phytoestrogens for their cardioprotective effects, which exerted regulatory effects on NO synthesis through differential regulation of estrogen receptors. It can be employed as a basis for evaluating the beneficial effects of phytoestrogens in the treatment of patients at risk of cardiovascular disease.

Theoretical Study of the Elastic and the Thermodynamic Properties of Re$_2$C under High Pressure

Hui-Ru Lei,Li-Hong Zhang,Xu Li,Xiao-Zhen Gao,Jing Li 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.11

The structural properties of Re$_2$C in anti-MoS$_2$ and anti-ReB$_2$ structures have been investigated by using the pseudopotential plane wave methods based on the density functional theory. The anti-ReB$_2$ structure is found to be more stable than the anti-MoS$_2$ structure. In particular, for the first time, we have studied the elastic properties of Re$_2$C in the anti-ReB$_2$ structure under high pressure. The ductile-brittle behavior and Vickers hardness for the anti-ReB$_2$ structure are also been analyzed. In addition, the Debye temperature, heat capacity and thermal expansion coefficient are discussed by using the quasiharmonic Debye model method.

Tumor-Derived Transforming Growth Factor-β is Critical for Tumor Progression and Evasion from Immune Surveillance

Li, Zheng,Zhang, Li-Juan,Zhang, Hong-Ru,Tian, Gao-Fei,Tian, Jun,Mao, Xiao-Li,Jia, Zheng-Hu,Meng, Zi-Yu,Zhao, Li-Qing,Yin, Zhi-Nan,Wu, Zhen-Zhou Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Tumors have evolved numerous mechanisms by which they can escape from immune surveillance. One of these is to produce immunosuppressive cytokines. Transforming growth factor-${\beta}$(TGF-${\beta}$) is a pleiotropic cytokine with a crucial function in mediating immune suppression, especially in the tumor microenvironment. TGF-${\beta}$ produced by T cells has been demonstrated as an important factor for suppressing antitumor immune responses, but the role of tumor-derived TGF-${\beta}$ in this process is poorly understood. In this study, we demonstrated that knockdown of tumor-derived TGF-${\beta}$ using shRNA resulted in dramatically reduced tumor size, slowing tumor formation, prolonging survival rate of tumor-bearing mice and inhibiting metastasis. We revealed possible underlying mechanisms as reducing the number of myeloid-derived suppressor cells (MDSC) and $CD4^+Foxp3^+$ Treg cells, and consequently enhanced IFN-${\gamma}$ production by CTLs. Knockdown of tumor-derived TGF-${\beta}$ also significantly reduced the conversion of na$\ddot{i}$ve $CD4^+$ T cells into Treg cells in vitro. Finally, we found that knockdown of TGF-${\beta}$ suppressed cell migration, but did not change the proliferation and apoptosis of tumor cells in vitro. In summary, our study provided evidence that tumor-derived TGF-${\beta}$ is a critical factor for tumor progression and evasion of immune surveillance, and blocking tumor-derived TGF-${\beta}$ may serve as a potential therapeutic approach for cancer.

Gene Expression Profiles of HeLa Cells Impacted by Hepatitis C Virus Non-structural Protein NS4B

( Yi Zheng ),( Lin Bai Ye ),( Jing Liu ),( Wei Jing ),( Khalid A. Timani ),( Xiao Jun Yang ),( Fan Yang ),( Wei Wang ),( Bo Gao ),( Zhen Hui Wu ) 생화학분자생물학회 2005 BMB Reports Vol.38 No.2

By a cDNA array representing 2308 signal transductionrelated genes, we studied the expression profiles of HeLa cells stably transfected by Hepatitis C virus nonstructural protein 4B (HCV-NS4B). The alterations of the expression of four genes were confirmed by real-time quantitative RT PCR; and the aldo-keto reductase family 1, member Cl (AKR1C1) enzyme activity was detected in HCV-NS4B transiently transfected HeLa cells and Huh-7, a human hepatoma cell line. Of the 2,308 genes we examined, 34 were up-regulated and 56 were down-regulated. These 90 genes involved oncogenes, tumor suppressors, cell receptors, complements, adhesions, transcription and translation, cytoskeletion and cellular stress. The expression profiling suggested that multiple regulatory pathways were affected by HCV-NS4B directly or indirectly. And since these genes are related to carcinogenesis, host defense system and cell homeostatic mechanism, we can conclude that HCV-NS4B could play some important roles in the pathogenesis mechanism of HCV.

Prediction of postoperative pancreatic fistula using a nomogram based on the updated definition

Cheng-Xiang Guo,Yi-Nan Shen,Qi Zhang,Xiao-Zhen Zhang,Jun-Li Wang,Shun-Liang Gao,Jian-Ying Lou,Ri-Sheng Que,Tao Ma,Ting-Bo Liang,Xue-Li Bai 대한외과학회 2020 Annals of Surgical Treatment and Research(ASRT) Vol.98 No.2

Purpose: The International Study Group on Pancreatic Fistula’s definition of postoperative pancreatic fistula (POPF) has recently been updated. This study aimed to identify risk factors for POPF in patients having pancreaticoduodenectomy (PD) and to generate a nomogram to predict POPF. Methods: Data on 298 patients who underwent PD from March 2012 to October 2017 was retrospectively reviewed and POPF statuses were redefined. A nomogram was constructed using data from 220 patients and validated using the remaining 78 patients. Independent risk factors for POPF were identified using univariate and multivariate analyses. A predictive nomogram was established based on the independent risk factors and was compared with existing models. Results: Texture of the pancreas, size of the main pancreatic duct, portal vein invasion, and definitive pathology were the identified risk factors. The nomogram had a C-index of 0.793 and was internally validated. The nomogram performed better (C-index of 0.816) than the other most cited models (C-indexes of 0.728 and 0.735) in the validation cohort. In addition, the nomogram can assign patients into low- (less than 10%), intermediate- (10% to 30%), and high-risk (equal or higher than 30%) groups to facilitate personalized management. Conclusion: The nomogram accurately predicted POPF in patients having PD.