1.Development of rapid determination of carbon dioxide combining power without mercury.
Chinese Journal of Medical Instrumentation 2012;36(3):227-234
A new type of instrument that called the rapid determination of carbon dioxide combining power without mercury is proposed. The performance of the instrument in accordance to the requirements in ISO15189 of laboratory accreditation has been evaluated. The results showed that, this instrument is safe, pollution-free, accurate and practical.
Carbon Dioxide
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analysis
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Clinical Chemistry Tests
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instrumentation
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Equipment Design
2.Clinical features of right temporal lobe variant of semantic dementia
Fangfang GE ; Zhenxin ZHANG ; Yanfeng LI ; Ruixue CUI ; Jing YUAN ; Bo HOU ; Feng FENG
Chinese Journal of Neurology 2014;47(5):293-298
Objective To identify the clinical profile and neuro-imaging findings of the right temporal lobe variant of semantic dementia (RTLV),and to understand the relationship between anatomic and function by comparison to the left temporal lobe atrophy.Methods Of 70 patients with diagnosis of frontotemporal dementia in our memory clinic,three patients with right temporal lobe atrophy were identified based on the MRI scans.We obtained the profile of cognitive function,behavior and personality changes in these 3 patients and compared them with those in 5 semantic dementia (SD) patients with predominant leftsided temporal lobe atrophy.We also underwent 18F-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG-PET) with statistical parametric mapping analysis in these 3 patients.Results In RTLV patients,the most prominent cognitive deficits were impairment of prosopagnosia,and getting lost.Variety behavioral symptoms including apathy,social disinhibition,stereotypy,compulsive behaviors were more prevalent in early course for patients with RTLV,which were different from SD patients with semantic loss began with anomia or single-word comprehension.18F-FDG-PET scan showed decreased metabolism mainly in right temporal lobe and in other brain regions with varying degrees.Conclusions The RTLV is clinical heterogeneous.Prosopagnosia,behavioral changes and getting lost are the main features in the early course.It therefore,might be proposed a separate clinical entity.
3.Proliferation activating effects of Mtb-Ag on γδT cells and its effects on expression of CD69 molecules inγδT cells
Hongmei JIN ; Li ZHU ; Keqiang WANG ; Guo LIU ; Yanchao DUAN ; Zhenxin YUAN
International Journal of Biomedical Engineering 2015;38(1):29-31,35
Objective To activate and amplify γδT cells with low molecular peptide antigen of Mycobacterium tuberculosis low molecular peptide antigen (Mtb-Ag),and to investigate the expression of CD69 molecules on γδT cellular surface.Methods Healthy human peripheral blood mononuclear cells (PBMC) were obtained and separated,then positive cells were isolated by immuno-magnetic beads selection,and the proportion of γδT cells in the PBMCs was detected by fluorescent monoclonal TCR γδT-PE staining and flow cytometry.Expression of CD69 molecules in γδT cells was detected by γδ-PE/CD69 FITC double staining.Results The proportion of γδT cells was (4.9±1.85)% in freshly obtained PBMC,(69.2±6.57)% after 10 d of Mtb-Ag activation,and (99.3±8.92)% after immuno-magnetic beads selection.The expression of CD69 molecules in γδT cells reached the peak (75.2%) at 24 h after initial Mtb-Ag stimulation,and reached the peak (72.0%) at 6 h after second stimulation.Conclusions MtbAg can specifically stimulate the proliferation of γδT cells in the PBMC.Both its initial and the second stimulation can specifically activate γδT cells.
4.Osteogenic properties of polyacrylamide-modified gelatin methacryloyl grafted titanium alloy scaffold
Fuchao CHU ; Zhenxin WANG ; Dazhen ZHANG ; Feng YUAN
Chinese Journal of Tissue Engineering Research 2024;28(22):3472-3477
BACKGROUND:Titanium and its alloys are widely used in orthopedic implants due to their excellent biocompatibility,corrosion resistance,and mechanical properties.However,it has biological inertia itself,cannot provide a good growth environment for osteoblasts,and it is difficult to form good osseointegration. OBJECTIVE:To construct a composite hydrogel material of gelatin methacryloyl and polyacrylamide on the surface of titanium alloy scaffold,and analyze its osteogenic ability in vitro. METHODS:Gelatin methacryloyl was mixed with acrylamide.Crosslinking agent and catalyst were added to synthesize gelatin methacryloyl and acrylamide(Gelma-PAAM)composite hydrogel.The titanium alloy scaffold modified by affinity silane was mixed with the Gelma hydrogel and Gelma-PAAM composite hydrogel to complete the loading(recorded as Ti-Gelma and Ti-Gelma-PAAM,respectively).The swelling ratio and degradation rate of the two hydrogels on the surface of the scaffold were compared.The bonding state between hydrogels and titanium alloy was observed by scanning electron microscope.Rat bone marrow mesenchymal stem cells were inoculated into Ti,Ti-Gelma and Ti-Gelma-PAAM scaffolds,separately.Cell proliferation,adhesion,and osteogenic differentiation were detected. RESULTS AND CONCLUSION:(1)Compared with Gelma hydrogel,Gelma-PAAM hydrogel had higher swelling rate and lower degradation rate.(2)Scanning electron microscope showed that the surface of the two kinds of hydrogels was honeycomb structure.After being combined with porous titanium alloy scaffold,the film was wrapped on the surface of scaffold and filled with pores.Among them,the Gelma-PAAM composite hydrogel coated the scaffold more fully.(3)CCK-8 assay and live/dead fluorescence staining showed that bone marrow mesenchymal stem cells proliferated well after coculture with Ti-Gelma and Ti-Gelma-PAAM scaffolds and maintained high activity.After osteogenic induction culture,alkaline phosphatase activity,calcium deposition,and osteogenic gene expression of cells of titanium alloy scaffold group were the lowest,and alkaline phosphatase activity,calcium deposition,and osteogenic gene expression of cells of Ti-Gelma-PAAM scaffold group were the highest.(4)Phalloidin cytoskeletal staining exhibited that the cells of pure titanium alloy scaffold group and Ti-Gelma scaffold group were sparse and insufficiently extended,while the cells of Ti-Gelatin-PAAM group had the most adequate stretching and the densest filamentous actin.(5)The results show that Gelma-PAAM hydrogel has good biocompatibility and osteogenic ability,and is more suitable for osteogenic modification on the surface of titanium alloy than Gelma hydrogel.
5.Fe-Co/ZIF-8@SLC-0111-HA composite nanoplatform enhances feasibility of tumor chemodynamic therapy
Zhenxin WANG ; Peng ZHOU ; Fuchao CHU ; Dazhen ZHANG ; Feng YUAN
Chinese Journal of Tissue Engineering Research 2024;28(29):4612-4619
BACKGROUND:The low catalytic activity and lack of targeting of commonly used metal ions have severely limited the clinical application of chemodynamic therapy in tumor treatment.On the other hand,although the composite nanoplatforms are endowed with tumor-targeting functions by surface functionalization,the lack of tumor microenvironment acidity also severely weakens the efficacy of chemodynamic therapy. OBJECTIVE:To prepare novel composite nanoplatforms and assess their feasibility to enhance the effects of chemodynamic therapy at the cellular level. METHODS:SLC-0111-loaded zeolite imidazole framework-8 doped with divalent iron ions(Fe2+)and divalent cobalt ions(Co2+)(Fe-Co/ZIF-8@SLC-0111)was synthesized by ion-exchange reaction and self-assembly,and loaded with hyaluronic acid(HA)by electrostatic adsorption,followed by obtaining the target nanoparticles Fe-Co/ZIF-8@SLC-0111-HA(abbreviated as FC-S).Meanwhile,nanoparticles Fe-Co/ZIF-8-HA(abbreviated as FC)without SLC-0111 were synthesized by the same method.The nanocomposite platform was tested for particle size,zeta potential,surface morphology,in vitro reactive oxygen species generation,and ability to consume glutathione.Human osteosarcoma cell MG-63 and mouse fibroblast cell L929 were used as experimental subjects.The cytotoxicity of FC-S was detected by CCK-8 assay.Human osteosarcoma cell MG-63 was used as the experimental object to detect the cell internalization of FC-S.In addition to H2O2,the effects of FC-S and FC on intracellular pH,carbonic anhydrase 9 protein expression,cell viability and apoptosis,intracellular reactive oxygen species and glutathione content,and mitochondrial membrane potential were investigated. RESULTS AND CONCLUSION:(1)The FC-S composite nanoplatform was successfully prepared with a well-defined rhombic dodecahedral structure,uniform size and good dispersion.Its particle size was about 323 nm;zeta potential was about-11.1 mV,and the nanoplatform had a certain reactive oxygen species generation capacity in vitro.(2)FC-S nanoplatforms accumulated intracellularly in a time-dependent manner and could successfully escape from lysosomes.When the mass concentration of FC-S was≤20 μg/mL,there was no obvious cytotoxicity to MG-63 cells and L929 cells,and 20 μg/mL FC-S was selected to act on MG-63 cells in subsequent experiments.(3)Compared with FC group,the protein expression of carbonic anhydrase 9 in MG-63 cells in FC-S group was decreased(P<0.01);the intracellular acidic environment was enhanced;the content of reactive oxygen species was increased(P<0.001);the mitochondrial damage was aggravated;the number of dead cells was increased,and the apoptosis rate was increased(P<0.001).(4)The results indicate that FC-S,as a novel composite nanoplatform,can effectively improve the weakly acidic microenvironment in tumor cells and enhance the level of intracellular reactive oxygen species production,thus enhancing the efficacy of chemodynamic therapy.