2.Plasmid-mediated carbapenemase KPC-2 in a strain of Klebsieila pneumoniae
Xing-Guo ZHANG ; Xiao-Xing DU ; Rong ZHANG ; Ze-Qing WEI ; Yun-Song YU ; Ya-Gang CHEN ; Lan-Juan LI ;
Chinese Journal of Laboratory Medicine 2003;0(09):-
Objective To investigate the resistant mechanism of imipenem-resistant K. pneumoniae.Methods The minimal inhibitive concentrations (MICs) of the antimicrobial agents were determined by Etest.Isoelectric focusing electrophoresis (IEF),plasmid extraction,conjugation, transformation,PCR amplification,cloning and sequencing were carried out for analyzing the encoding gene of ?-1actamases.Results Three kinds of ?-1actamases were detected with pIs of 7.2,6.7,and 5.4.in a clinical strain of K.pneumoniae.These ?-1actamases were TEM-I (pI,5.4),SHV-12 (pI,8.2) and KPC-2 ( pI,6.7 ) confirmed by sequencing of the PCR products.Only one band of ?-1actamase with pI 6.7 was displayed in the transformant.A 1500 bp segment,which contained the KPC-2 gene confirmed by nucleotide sequence analysis,was cloned from a 60 000 bp plasmid of the transformant.Conclusion The strain of K.pneumoniae resistant to imipenem produces a plasmid-mediated carbapenemase KPC-2 which belongs to Bush group 2f,class A ?-1actamase.
3.Study of estradiol on treatment of preeclampsia in rat model
Xueyan WANG ; Qing XIONG ; Chao WANG ; Bing XIAO ; Shu ZHOU ; Rong ZHOU ; Aiyun XING
Chinese Journal of Obstetrics and Gynecology 2000;0(11):-
Objective To evaluate whether estradiol can inhibit and cure the inflammation of experimental preeclampsia in rats. Methods Experimental preeclampsia was induced in 14-day-pregnant rats by infusion of endotoxin (1.0 ?g/kg). Rats with normal pregnancy were infused with sodium chloride solution.A group of preeclampsia rats was injected with 17?-estradiol (17?-E_2, 1 mg?kg -1 ?d -1 ). Blood pressure, albuminuria,inflammation associated adhesion molecule CD_ 49d and tumor necrosis factor-?(TNF-?) were assessed. Results On pregnant day 19, for normal pregnancy group(group C) the blood pressure was (120.4?2.0)mm Hg (1 mm Hg=0.133 kPa),urinary protein (0.47?0.06)mg/24 hours;for experimental preeclampsia group(group A) blood pressure was (134.2?2.4) mm Hg,urinary protein(0.79?0.10)mg/24 hours; for experimental preeclampsia with 17?-E_2 treatment group (group B) blood pressure was(123.3?1.7)mm Hg,urinary protein (0.51?0.08)mg/24 hours. A significant increase of blood pressure and urinary albumin was observed in group A. CD_ 49d expression and TNF-? concentration were also increased. 17?-E_2 reduced the expression of CD_ 49d , concentration of TNF-?,blood pressure and albuminuria of experimental preeclampsia. However, the weight of fetuses in 17?-E_2 treatment group were less than that in other groups. Conclusion 17?-E_2 can improve the symptoms of experimental preeclampsia,but its effects on fetus need to be further studied.
5.Expression of nitric oxide and γ -aminobutyric acid in the retina of two kinds of amblyopia cats
Han-Min, WANG ; Ao, RONG ; Li-Juan, MO ; Qing-Song, LI ; Xing-Ru, ZHANG
International Eye Science 2016;16(11):2006-2009
AIM: To study the role of nitric oxide ( NO ) and γ-aminobutyric acid ( GABA) in the formation of amblyopia by establishing 2 different types of amblyopic models.METHODS:A total of 18 aged 3-week kittens were randomly divided into monocular deprivation, strabismus and normal groups. All types of amblyopia were developed in the experimental eyes that were detected by P-VEP 12wk later. The cats were killed and the immunocytochemistry staining method were applied to observe under the light microscope the changes of distribution and positive cells areas of NO and GABA across the amblyopic retinal, compared to that from the normal cats of identical age.
RESULTS: The P-VEP showed that the amplitude of wave P1 was lower (P<0. 05) and the P1 latent time was longer ( P<0. 05 ) in two types of amblyopic cats than those in the normal cats. Compared to the normal cats, the NO and GABA positive cells areas were obviously reduced ( P<0. 05 ) across the retina in the amblyopic cats. But no significant difference was found between two kinds of amblyopic cats.
CONCLUSION:The NO and GABA play an important role in the formation of amblyopia in the level of retinal.
6.Repair of acutely injured spinal cord through constructing tissue-engineered neural complex in adult rats.
Yu PU ; Qing-shan GUO ; Ai-min WANG ; Si-yu WU ; Shu-xing XING ; Zhong-rong ZHANG
Chinese Journal of Traumatology 2007;10(3):171-176
OBJECTIVETo construct tissue-engineered neural complex in vitro and study its effect in repairing acutely injured spinal cord in adult rats.
METHODSNeural stem cells were harvested from the spinal cord of embryo rats and propagated in vitro. Then the neural stem cells were seeded into polyglycolic acid scaffolds and co-cultured with extract of embryonic spinal cord in vitro. Immunofluorescence histochemistry and scanning electron microscope were used to observe the microstructure of this complex. Animal model of spine semi-transection was made and tissue-engineered neural complex was implanted by surgical intervention. Six weeks after transplantation, functional evaluation and histochemistry were applied to evaluate the functional recovery and anatomic reconstruction.
RESULTSThe tissue-engineered neural complex had a distinct structure, which contained neonatal neurons, oligodendrocytes and astrocytes. After tissue-engineered neural complex was implanted into the injured spinal cord, the cell components such as neurons, astrocytes and oligodendrocytes, could survive and keep on developing. The adult rats suffering from spinal cord injury got an obvious neurological recovery in motor skills.
CONCLUSIONSThe tissue-engineered neural complex appears to have therapeutic effects on the functional recovery and anatomic reconstruction of the adult rats with spinal cord injury.
Animals ; Female ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries ; surgery ; Stem Cell Transplantation ; methods ; Tissue Engineering ; methods
7.Histone deacetylase inhibitor promotes differentiation of embryonic stem cells into neural cells in adherent monoculture.
Xing YAO ; Jia-rong ZHANG ; Hua-rong HUANG ; Li-cheng DAI ; Qing-jun LIU ; Ming ZHANG
Chinese Medical Journal 2010;123(6):734-738
BACKGROUNDEmbryonic stem (ES) cells poss unlimited self-renewal capacity and the ability to differentiate into cell of all three germ layers in vitro. Induced differentiation of ES cells to neural lineage cells has great potential in basic study of neurogenesis and regeneration therapy of neurodegenerative diseases. Histone deacetylase (HDAC) inhibitors enhance histone acetylation so that globularly activate gene expression and may initiate multilineage differentiation. In this study, we aimed to develop a method to induce the differentiation of ES cells to neural cells combining HDAC inhibition and neural cell selection.
METHODSIn this study, we used HDAC inhibitor sodium butyrate (NaB) to induce the differentiation of mouse embryonic stem cells to neural cells through monolayer culture. After differentiation initiation by histone deacetylase inhibitor sodium butyrate, neural cells were induced and selected with a serum free culture system.
RESULTSHomogeneous neurons without glial cells demonstrated by molecular marker expression were differentiated with the method. The resultant neurons were excitable.
CONCLUSIONThe method combined differentiation induction effect of HDAC inhibitors and selective culture system to derive neural cells from ES cells, and implied the involvement of epigenetic regulation in neural differentiation.
Animals ; Butyrates ; pharmacology ; Cell Adhesion ; Cell Cycle ; drug effects ; Cell Differentiation ; drug effects ; Cells, Cultured ; Embryonic Stem Cells ; cytology ; drug effects ; Fibroblast Growth Factor 2 ; pharmacology ; Histone Deacetylase Inhibitors ; pharmacology ; Mice ; Neurons ; cytology ; physiology
8.Construction and expression of human stathmin gene eukaryotic expression vector and its effect on esophageal cancer cells.
Feng WANG ; Liu-Xing WANG ; Rui-Lin WANG ; Qing-Xia FAN ; Pei-Rong ZHAO
Chinese Journal of Oncology 2008;30(3):179-183
OBJECTIVETo construct an eukaryotic expression vector of human stathmin gene and to assess its effect on esophageal cancer EC9706 cells.
METHODSStathmin cDNA coding sequence was amplified by RT-PCR from Eca109 cells and was cloned into pMD18-T vector. After identifying and sequencing, the correct inserting stathmin gene was sub-cloned into eukaryotic expression vector pEGFP-C2. EC9706 cells were transfected with this recombinant plasmid and control plasmid using Lipofectamine 2000, and the stable intergrant was selected with G418 medium. The expression of enhanced green fluorescent protein (EGFP) protein was detected by fluorescence microscopy and EGFP/stathmin fusion protein by Western blot assay in transfected EC9706 cells. The growth curve of the two stably transfected cells was protracted with cell counting. FACS was used to detect the cell cycle. The clone formation rate in plate and in nude mice was tested to investigate the tumorigenic characteristics of the two stably transfected cells in vitro and vivo.
RESULTSA 450 bp coding sequence of stathmin cDNA was amplified by RT-PCR, which was cloned into pMD18-T vector. After identified with restriction enzyme the recombinant plasmid pMD18-T-stathmin containing reverse inserting sequence was constructed successfully. Then, the sub-clone pEGFP-stathmin was sequenced, confirming that the recombinant vector was right. The recombinant plasmid pEGFP-stathmin and pEGFP-C2 vector were transfected separately into EC9706 cells. After selecting with G418, the cells were transfected steadily. EGFP in EC9706 cells was observed after transfection by fluorescence microscopy. The expressed product was proved to be 46,000 EGFP/stathmin fusion protein by Western blot. Compared with those transfected with pEGFP-C2, the growth of cells transfected with pEGFP-stathmin became slow, the cells were swelled, the cell cycle was blocked at G2/M phase, the average clone formation rate decreased in vitro, and the tumorigenicity of inoculated cells in nude mice was decreased.
CONCLUSIONThe recombinant eukaryotic expression vector pEGFP-stathmin has been constructed successfully. It expresses steadily in esophageal cancer cells and inhibits the proliferation and tumorigenicity of transfected cells.
Animals ; Cell Cycle ; Cell Proliferation ; Escherichia coli ; genetics ; Esophageal Neoplasms ; metabolism ; pathology ; Female ; Genetic Vectors ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Plasmids ; Recombinant Fusion Proteins ; genetics ; metabolism ; Stathmin ; genetics ; metabolism ; Transfection
9.Testosterone deficiency: an independent risk factor of cardiovascular disease.
Xing-Rong QING ; Xue-Jun SHANG ; Yu-Feng HUANG
National Journal of Andrology 2013;19(8):742-747
Serum testosterone levels and gonad function decline with the aging of males. Large-scale epidemiological investigations, mechanism researches and clinical studies conducted in recent years have shown that physiological androgens are critical for the protection of the cardiovascular system. Testosterone deficiency in aging males is associated with several cardiovascular risk factors which include hyperlipidemia, diabetes, hypertension, thrombogenic and fibrinolytic dysfunction and inflammation. It can also lead to endothelial and vascular dysfunction, accelerate the formation of atherosclerosis and increase the morbidity of cardio-vascular disease.
Cardiovascular Diseases
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epidemiology
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Humans
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Male
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Middle Aged
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Risk Factors
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Testosterone
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deficiency
10.Lipopolysaccharide affects male reproductive function through Toll-like receptors.
Xu-Xin ZHAN ; Xing-Rong QING ; Xue-Jun SHANG ; Yu-Feng HUANG
National Journal of Andrology 2013;19(2):163-168
Reproductive tract infection is one of the factors of male infertility, but the mechanisms responsible are hitherto poorly defined. Recent studies show that one of the microbial pattern-recognition receptors, Toll-like receptor (TLR) signaling pathway, plays a critical role in inflammation-induced male infertility. Lipopolysaccharide (LPS), a major component in the cell wall of gram-negative bacteria, could induce inflammatory response through TLRs. A large number of researches suggest that TLRs express widely in the male reproductive tract and LPS-induced inflammatory reaction through TLRs may affect male fertility. This article presents an overview on how LPS-induced inflammation through TLRs affects male fertility in terms of its influence on the testis, epididymis and sperm quality.
Genital Diseases, Male
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metabolism
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pathology
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Gram-Negative Bacteria
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metabolism
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Humans
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Infertility, Male
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metabolism
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pathology
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Inflammation
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Lipopolysaccharides
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adverse effects
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Male
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Toll-Like Receptors
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metabolism