2.The primary study on the detection of sterigmatocystin by biologic enzyme electrode modified with the multiwall carbon nanotubes.
Dong-Sheng YAO ; Sheng-Mei WEN ; Da-Ling LIU ; Chun-Fang XIE ; Yan BAI ; Yan-Hong RAN
Chinese Journal of Biotechnology 2004;20(4):601-606
Sterigmatocystin (ST), the secondary metabolite of many kinds of filamentous fungi, is a potent carcinogen structurally related to the aflatoxins (AFT). With similar chemical structure, sterigmatocystion behaves much the homogeneous properties to aflatoxins, both of these mycotoxins exhibit similar biological properties due to their bisfuranoid structure. Since the common, and even heavier pollution, found in foods and feeds-stuff, sterigmatocystion is more harmful than aflatoxins. The reported detection methods of sterigmatocystion included the Thin-layer Chromatography, the High-Performance-Liquid Chromatography, the Enzyme-Linked Immunosorbant Assay and the PCR detection to the toxic gene, however studies about both easy and inexpensive electro-chemical methods have not been found. Our previous studies had discovered that Sterigmatocystin (ST) exist similar sensitivity towards aflatoxin-detoxifizyme (ADTZ), which we had isolated from a fungus, as aflatoxin does. In this work, the preliminary study on electrochemical analysis and determination of ST with triplet electrode enzyme-biosensor system (Ag/AgCl as the reference electrode, Pt and Au as the pair and work electrode, respectively) was carried out. Multiwall-carbon-nanotube (MWNT) had been used to increase the electron transportation on electrode. In the research, the Au electrode was modified by MWNT-immobilized ADTZ, and then the voltammertric behavior of ST was studied by means of cyclic voltammogram analysis and different pulse analysis. Autoprobe CP Research Atomic Force Microscope and TECNAI 10 Transmission Electron Microscope, had been used to detect the MWNT as well as the surface of MWNT-modified ADTZ. The voltammertric behavior of ST was studied by means of cyclic voltammogram analysis and different pulse analysis. The results show that the red-ox peak potential of ST is at the point of -600 mV, the linear detection range is from 8.32 x 10(-5) to 66.56 x 10(-5) mg/mL, the detection limit is at 8.32 x 10(-5) mg/mL, and the response time is 10 seconds. This study provided a good basic work for further research.
Biosensing Techniques
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methods
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Electrochemistry
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Microscopy, Atomic Force
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Microscopy, Electron, Transmission
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Nanotubes, Carbon
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chemistry
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Sterigmatocystin
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analysis
3.Multiple transmission electron microscopic image stitching based on sift features.
Mu LI ; Yanmeng LU ; Shuaihu HAN ; Zhuobin WU ; Jiajing CHEN ; Zhexing LIU ; Lei CAO
Journal of Southern Medical University 2015;35(9):1251-1257
We proposed a new stitching method based on sift features to obtain an enlarged view of transmission electron microscopic (TEM) images with a high resolution. The sift features were extracted from the images, which were then combined with fitted polynomial correction field to correct the images, followed by image alignment based on the sift features. The image seams at the junction were finally removed by Poisson image editing to achieve seamless stitching, which was validated on 60 local glomerular TEM images with an image alignment error of 62.5 to 187.5 nm. Compared with 3 other stitching methods, the proposed method could effectively reduce image deformation and avoid artifacts to facilitate renal biopsy pathological diagnosis.
Algorithms
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Artifacts
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Humans
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Image Processing, Computer-Assisted
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methods
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Kidney Glomerulus
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ultrastructure
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Microscopy, Electron, Transmission
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methods
4.A Case of Orf Identified by Transmission Electron Microscopy.
Fen PENG ; Zhou CHEN ; Shu-Ying ZHENG ; Hou-Min LI ; Juan DU ; Jian-Zhong ZHANG
Chinese Medical Journal 2016;129(1):108-109
5.Investigation on the technique of three dimensional reconstruction and analysis of series slices of images.
Jing LI ; Haiyan ZHAO ; Jingqiang ZHANG ; Qinfen ZHANG ; Kunpeng LI
Journal of Biomedical Engineering 2006;23(6):1183-1190
The new techniques of three-dimensional (3D) reconstruction and segmentation, display and analysis of series slices of images including microscopic wide field optical sectioning by deconvolution method and Cryoelectron microscope slices by electron tomography (ET) and series of computed tomography (CT) were investigated. As a result, this paper presents the 3D reconstruction segmentation display, and analysis results of pollen spore, chaperonin, head, cervical vertabra, tibia and carpale. Mean while, this paper also proposes the application of these new techniques in biomedical field.
Humans
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Image Interpretation, Computer-Assisted
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methods
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Imaging, Three-Dimensional
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Microscopy, Electron, Transmission
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methods
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Tomography
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methods
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Tomography, X-Ray Computed
6.Quantitative analysis of host cells growing into canine homograft valved aortic and pulmonary artery.
Jian-hua YU ; Hong-wei GUO ; Shi-qiu SONG
Chinese Medical Journal 2011;124(9):1422-1426
BACKGROUNDCryopreserved conduit valved homografts (CVH) have been widely used in surgical treatment of cardiac disease. This study aimed to determine the extent of host cell ingrowth and the durability and immunogenicity of CVH, and to compare the performance of CVH stored at 4°C and CVH cryopreserved in liquid nitrogen at -196°C.
METHODSHeterotopic transplants of canine CVH stored at 4°C (n = 14) and cryopreserved in liquid nitrogen (n = 14) were made onto the abdominal aorta of recipient dogs. Animals were sacrificed at 7 and 15 days and at 1, 3, 6, 9, and 12 months after transplantation to excise the implanted CVHs. Tissue DNA extraction and quantitative polymerase chain reaction (PCR) were performed to calculate the ratio of donor cells and host cells in the CVH. The tissue viability of CVH after implantation was analyzed by detecting alkaline fibroblast growth factor 2 (FGF-2) using immunohistochemical staining and by observation under transmission electron microscope and scanning electron microscope.
RESULTSAll the animals survived and recovered well. There were few repopulating host cells (0.04% - 0.83%) in the implanted CVH at 7 or 15 days. The ratio of ingrowing host cells into the CVH continued rising after implantation and reached 40% - 47% in the 12th month postoperation. Histology, transmission electron microscopy and FGF-2 immunohistochemical staining indicated that fibroblasts and the host's endothelial cells were the main cellular elements invading the CVH. There were no significant differences in results between CVH stored at 4°C and CVH cryopreserved in liquid nitrogen.
CONCLUSIONSHost cells growing into CVH are very important for maintaining the long-term structure and function of the implanted CVH. There is no significant difference between CVH storing at 4°C or in liquid nitrogen in regard to the ingrowth of host cells or of morphologic features after CVH allografting.
Animals ; Aorta ; transplantation ; ultrastructure ; Dogs ; Immunohistochemistry ; Microscopy, Electron, Transmission ; Polymerase Chain Reaction ; Pulmonary Artery ; transplantation ; ultrastructure ; Transplantation, Homologous ; methods
8.Effect of alexandrite laser treatment for hair removal in Tibet mini-pigs.
Dong ZENG ; Wen-lin YU ; Yuan BI ; Chuan-hong YANG ; Huang-wen LAI ; Zhi-qi HU
Journal of Southern Medical University 2009;29(4):697-700
OBJECTIVETo observe the histological and ultrastructural changes of the skin and hair follicles following hair removal by alexandrite laser in Tibet mini-pigs.
METHODSTwelve healthy Tibet mini-pigs with dark hair were treated with alexandrite laser for hair removal. The skin specimens were taken immediately and at 1 h and 1, 3, 5, 10, 15, 30, 60 days after the laser treatment for observation under optical and transmission electron microscope.
RESULTSLaser hair removal resulted in extensive coagulation necrosis, carbonization and falling of the subcutaneous hair shafts, and some of the cells in the outer root sheath and hair bulb underwent degenerative and necrotic changes. One hour after laser treatment, the cells in the outer root sheath and bulb exhibited nuclear condensation, fragmentation and or karyolysis characteristic of cell apoptosis. The cell apoptosis reached the peak level on day 3 after the laser exposure, accompanied by endothelial degeneration in the hair papilla vessels, edema and lymphocyte infiltration in the dermal tissues. Tissue reaction and inflammation were relieved on day 5, and the dermal tissue and follicles recovered their normal structures on day 10. At 60 days after the treatment, the hair follicles decreased markedly but the structure of the residue follicles remained normal.
CONCLUSIONAlexandrite laser exposure results in selective destruction of the follicles by inducing direct coagulation and cell apoptosis to achieve permanent hair removal. Tibet mini-pigs with black hair can be used as the animal model of clinical laser hair removal.
Animals ; Hair Follicle ; radiation effects ; ultrastructure ; Hair Removal ; methods ; Lasers, Solid-State ; therapeutic use ; Microscopy, Electron, Transmission ; Swine ; Tibet
9.Warthin-starry silver method showing particulate matter in macrophage.
Biomedical and Environmental Sciences 2008;21(1):85-89
OBJECTIVETo verify whether Warthin-Starry (WS) silver method could detect the air particulate matter (PM)/dust particles (Ps) located within the macrophages in situ.
METHODSThere were 26 autopsy cases that resulted from cerebral hemorrhage (group A), silicosis (group B), and fetal death during pregnancy (group C). Samples were collected separately and serial sections were prepared from the lungs and lymph nodes and stained with hematoxylin and eosin (HE), WS silver, immunohistochemistry of CD68. Furthermore, ultrathin sections were taken from the WS positive serial sections of groups A and B. Ps were observed under a transmission electron microscope (TEM) and the elements of Ps were measured by X-ray spectrum analysis (X-RSA).
RESULTSIn both groups A and B, WS staining was positive for the larger and fine Ps, the so called "dust cells", but HE staining was almost negative for fine Ps. In group C, no larger or fine Ps were found. Immunohistochemical staining of CD68 certified that the "dust cells" containing Ps were macrophages. The results of TEM and X-RSA proved that the structure and elements of Ps belonged to PM indeed.
CONCLUSIONWS staining is a better than HE staining in showing the location of PM within macrophages.
Adolescent ; Adult ; Aged ; Child ; Female ; Humans ; Macrophages ; ultrastructure ; Male ; Microscopy, Electron, Transmission ; Middle Aged ; Silver Staining ; methods
10.Specification of Bacteriophage Isolated Against Clinical Methicillin-Resistant Staphylococcus Aureus
Ahmad NASSER ; Reza AZIZIAN ; Mohsen TABASI ; Jamil Kheirvari KHEZERLOO ; Fatemah Sadeghpour HERAVI ; Morovat Taheri KALANI ; Norkhoda SADEGHIFARD ; Razieh AMINI ; Iraj PAKZAD ; Amin RADMANESH ; Farid Azizi JALILIAN
Osong Public Health and Research Perspectives 2019;10(1):20-24
OBJECTIVES: The emergence of resistant bacteria is being increasingly reported around the world, potentially threatening millions of lives. Amongst resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) is the most challenging to treat. This is due to emergent MRSA strains and less effective traditional antibiotic therapies to Staphylococcal infections. The use of bacteriophages (phages) against MRSA is a new, potential alternate therapy. In this study, morphology, genetic and protein structure of lytic phages against MRSA have been analysed. METHODS: Isolation of livestock and sewage bacteriophages were performed using 0.4 μm membrane filters. Plaque assays were used to determine phage quantification by double layer agar method. Pure plaques were then amplified for further characterization. Sulfate-polyacrylamide gel electrophoresis and random amplification of polymorphic DNA were run for protein evaluation, and genotyping respectively. Transmission electron microscope was also used to detect the structure and taxonomic classification of phage visually. RESULTS: Head and tail morphology of bacteriophages against MRSA were identified by transmission electron microscopy and assigned to the Siphoviridae family and the Caudovirales order. CONCLUSION: Bacteriophages are the most abundant microorganism on Earth and coexist with the bacterial population. They can destroy bacterial cells successfully and effectively. They cannot enter mammalian cells which saves the eukaryotic cells from lytic phage activity. In conclusion, phage therapy may have many potential applications in microbiology and human medicine with no side effect on eukaryotic cells.
Agar
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Bacteria
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Bacteriophages
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Caudovirales
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Classification
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DNA
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Electrophoresis
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Eukaryotic Cells
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Head
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Humans
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Livestock
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Membranes
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Methicillin Resistance
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Methicillin-Resistant Staphylococcus aureus
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Methods
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Microscopy, Electron, Scanning Transmission
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Microscopy, Electron, Transmission
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Sewage
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Siphoviridae
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Staphylococcal Infections
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Tail