Deubiquitinase Mysm1 regulates differentiation of neural stem cells into astrocytes by regulating expressions of glial fibrillary acidic protein / 军事医学

Objective To investigate the effect of Mysm1 on the differentiation of neural stem cells(NSCs)into astrocytes and the possible mechanism.Methods NSCs were prepared from E12.5 cortices of wild-type C57BL/6 mice,cultured in vitro and induced to differentiate into astrocytes.Immunofluorescence staining,real-time quantitative PCR and Western blot assay were used to detect the expressions of Mysm1 during the differentiation of NSCs into astrocytes in vitro.Lentivirus was used to knock down Mysm1 expressions in NSCs before real-time quantitative PCR and Western blot assay were used to detect the knockdown efficiency.Immunofluorescence staining and Western blot assay were used to compare the differentiation of NSCs into astrocytes before and after Mysm1 knockdown in vitro.Transcriptomics was adopted to detect the differential gene after knockdown of Mysm1 in NSCs in vitro.Western blot assay was used to verify the changes of proteins associated with the differential gene.Cut-Tag was used to detect the enrichment of Mysm1 in the promoter region of glial fibrillary acidic protein(GFAP)genes during the differentiation of NSCs into astrocytes in vitro.After overexpression of GFAP following knockdown of Mysm1,immunofluorescence staining and Western blot assay were used to compare the differentiation of NSCs into astrocytes before and after overexpression in vitro.Results The expression of Mysm1 was gradually increased when NSCs were induced to differentiate into astrocytes in vitro.Mysm1 knockdown inhibited the differentiation of NSCs into astrocytes in vitro.Mysm1 affected the differentiation of NSCs into astrocytes by regulating the expression of GFAP.Overexpression of GFAP after Mysm1 knockdown partially rescued the ability of NSCs to differentiate into astrocytes.Conclusion Mysm1 regulates the differentiation of NSCs into astrocytes by epigenetically controlling GFAP transcription.

Development and evaluation of mild TBI rapid diagnostic strips based on GFAP labeled with quantum dots / 军事医学

Objective To establish an auxiliary method for diagnosis of mild traumatic brain injury based on serum GFAP rapid detection test strips using immunochromatographic technology labeled with quantum dot microspheres.Methods The quantum dot microspheres were coupled with GFAP antibodies.The detection conditions were optimized to obtain the fluorescence probe in order to prepare the immunochromatographic test strips.An auxiliary diagnostic method was established after optimization of detection conditions.Finally,the auxiliary diagnostic effect of the test strips was evaluated using clinical samples.Results The serum concentration of GFAP could be detected by the optimized test strips within 13 mins with a detection limit of 0.15 ng/mL,and no more than 70μL of the serum sample was required.In addition,good reproducibility was achieved by different batches of test strips(CV=10.7%).The detection sensitivity and specificity of the strips to mild traumatic brain injury using 51 clinical samples were 95.24%and 96.67%respectively,indicating good effects of detection.Conclusion The developed test strips are user-friendly with reliable results,which can facilitate field rapid diagnosis of mild traumatic brain injury in complicated wartime environments.

Evolution of animal models of hemorrhage shock / 军事医学

An animal model of hemorrhagic shock is widely applied .It is an important platform to clarify the pathogenic mechanism, develop hemostasis materials , test first aid equipments and filter resuscitation medications .This paper summa-rizes the commonly used animal models of hemorrhagic shock at home and abroad , focusing on animal selection , model cre-ation, influencing factors , and fields of application in order to provide useful reference for model selection and application by medical practitioners and researchers .

Treatment of radiation-induced intestinal mucosal injury with keratinocyte growth factor 2 mutant in mice / 军事医学

Objective To investigate the therapeutic effect of KGF-2 mutants on radiation-induced intestinal mucosal injury.Methods Specific pathogen free (SPF) female C57BL/6J mice were randomly divided into 4 groups, which were treated with/without KGF2 mutant and/or bone marrow cell transplantation.All the 4 groups were radiated with one-time whole bodyγ-ray exposure of 12 Gy.Also one untreated group was included as control.The therapeutic effect of recombi-nant human KGF-2 mutants on radiation-induced intestinal mucosal injury was analyzed by the survival rate at the 30th day, the pathological change and the apoptosis as well as autophagy status of small intestine at 72 hours after exposure.Results After irradiation, all the mice in the untreated group died within 9 days while the mice treated with KGF-2 mutant combined with bone marrow cell transplantation showed a 70%survival rate at the 30th day.We also found that intestinal mucosa of the mice in this group had a more intact structure, a higher level of autophagy and a lower level of apoptosis via HE staining and immunohistochemistry.Conclusion KGF-2 mutant has a significant therapeutic effect on radiation-induced intestinal mucosal injury.

Application of visible loop-mediated isothermal amplification ( LAMP ) technologies in detecting Oncomelania infected with Schistosoma japonicum / 军事医学

Objective To establish a simple and rapid detection technique for Oncomelania infected with Schistosoma japonicum(SJ), with high sensitivity and good specificity .Methods The gene fragment of SJ was amplified by PCR , and cloned into the T-vector to construct positive-reference.An isothermal nucleic acid amplification reaction system for detecting Oncomelania infected with SJ was set up , and its sensitivity was analyzed by detecting positive-reference diluted according to geometric proportion , and its specificity by detecting the genomic DNA of relative samples .Then, a corresponding means of purifying nucleic acid was designed to assemble a reagent detecting Oncomelania infected with SJ . This reagent was validated by detecting Oncomelania samples.Results The 213 bp amplified products were obtained and used to construct recombination T-vector for positive reference .An isothermal nucleic acid amplification reaction system was set up for detecting Oncomelania infected with SJ , and the amplification results could be simply determined by color change, with better sensitivity and specificity .The reagents for detecting Oncomelania infected with SJ were assembled , which could detect samples containing only 1% infected Oncomelania.Conclusion A visible detection method for Oncomelania infected with SJ is successfully established and validated .

Several proteins involved in absorption of cholesterol in small intestine / 军事医学

Several proteins are involved in the absorption of cholesterol in small intestine.Niemann-Pick C1 like 1 (NPC1L1) mainly mediates the absorption of cholesterol, and acyl-coenzyme A ( CoA)∶cholesterol acyltransferase 2 (ACAT2) catalyzes the free cholesterol absorpted by intestine into cholesterol ester,while unesterified free cholesterol is secreted into intestinal lumen by ATP-binding cassette(ABC) transporters G5/G8(ABCG5/ABCG8).Transcription factor liver X receptor( LXR) plays an important role in the process of intestinal cholesterol absorption.The research progress in NPC1L1,ABCG5/ABCG8,ACAT2 and LXR is reviewed in this article.

Advances in recombinase polymerase amplification / 军事医学

Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification technology first re-ported in 2006 by Piepenburg et al.This technology has been shown to typically work at temperatures ranging from 25 to 43℃and can detect products within 5-20 min.RPA technology requires little instrumentation for the nucleic acid amplifi-cation reaction and can be performed not only in PCR tubes , but also in simple devices′such as paper .Combined with probe-based detection methods or lateral flow dipstick assay , it can perform quantitative or visual detection respectively . RPA is a technology that is potentially ideal for point-of-care diagnosis and disease prevention and control ,characterized by high sensitivity, high efficiency, high specificity and user-friendliness.This paper introduces the advantages and develop-ment of RPA technology in reaction conditions and product detection ,summarizes the current applications of this technolo-gy,and predicts the trend of application of RPA technology in point-of-care diagnosis and disease prevention and control .

Cloning, expression and identification of IL-1ra-Fcepsilon fusion gene / 生物工程学报

Both interleukin-1 and IgE are important in the pathogenic mechanism of the allergy asthma. cDNA of interleukin-1receptor antagonist (IL-1ra) and IgE were cloned and a prokaryotic expression vector IL-1ra-Fcepsilon/pBV220 was constructed. The vector was transformed into Escherichia coli BL21(DE3). The fusion protein was expressed successfully in the form of inclusion body. The recombination protein of IL-1ra-Fcepsilon was highly purified by chromatography of gel filtration and ion exchange, which was identifited by Western blotting. The cell assay showed that the activity of IL-1ra-Fcepsilon was as high as IL-1ra in vitro after refolding. The pharmacokenetic profile of IL-1ra-Fcepsilon and L-1ra was analyzed, and the half time of IL-1ra-Fcepsilon is 4.78 times than that of IL-1ra.

Secretory expression and biological function of IGFBP-3 in eukaryotic cells / 生物工程学报

The cDNA of Insulin-like growth factor binding protein 3 was subcloned into a eukaryotic secretory expression vector pSectagA to construct pSectag-IGFBP3. Human renal cell carcinoma (RCC) 786-0 cells were transfected with pSectag-IGFBP3 using lipofectamine 2000. After 48 h, the secretory IGFBP-3 was tested and identified by western blotting. Meanwhile, Annexin V-EGFP stain was used to analyze the apoptosis of 786-0 cells induced by IGFBP-3. Secretory IGFBP-3 protein could express successfully in the 786-0 cells and the expressed IGFBP-3 directly displayed an apoptotic effect on the host cells. This work provides a basis for further study on the apoptosis-inducing mechanism of IGFBP-3 and the development of a new anti-tumor drug.