THE INTERRELATIONSHIP BETWEEN TUMOR CELLS'ELECTROPHORETIC MOBILITY,ADHESIVE AND INVASIVE ABILITIES,AND THEIR METASTATIC POTENTIAL

Investigations on the relationship between some tumor cell properties and their metastatic potential using different clones from two tumor cell lines are reported. CNE2L2(highly metastatic) and CNE2L4 (low metastatic) clones were isolated from human nasopharyngeal carcinoma CNE-2Z cell line. LA1. LAD and LA5 clones were isolated from mouse pulmonary adenocarcinoma LA795 cell line with different metastatic potentials. The results from both cell lines showed that the metastatic potential of tumor cell positively correlated with elecirophoretic mobility rate. adhesion with endothelial cells and in vitro and in vivo invasiveness. and negatively correlated with self-adhesion and adhesion to fibroblast cells. The data further confirmed the relationship between these factors and the metastatic potential of tumor cells.The results provide a theoretical basis for elucidating the mechanism of metastasis.

Virus Removal by Iron Coagulation Processes

Waterborne viruses account for 30% to 40% of infectious diarrhea, and some viruses could persevere for some months in nature and move up to 100 m in groundwater. Using filtration setups, coagulation could lessen virus charges as an efficient pre-treatment for reducing viruses. This work discusses the present-day studies on virus mitigation using coagulation in its three versions i.e., chemical coagulation (CC), enhanced coagulation, and electrocoagulation (EC), and debates the new results of virus demobilization. The complexity of viruses as bioparticles and the process of virus demobilization should be adopted, even if the contribution of permeability in virus sorption and aggregation needs to be clarified. The information about virion permeability has been evaluated by interpreting empirical electrophoretic mobility (EM). No practical measures of virion permeability exist, a clear link between permeability and virion composition and morphology has not been advanced, and the direct influence of inner virion structures on surface charge or sorption has yet to be conclusively demonstrated. CC setups utilizing zero-valent or ferrous iron could be killed by iron oxidation, possibly using EC and electrooxidation (EO) methods. The oxidants evolution in the iron oxidation method has depicted promising findings in demobilizing bacteriophage MS2, even if follow-up investigations employing an elution method are needed to secure that bacteriophage elimination is related to demobilization rather than sorption. As a perspective, we could be apt to anticipate virus conduct and determine new bacteriophage surrogates following subtle aspects such as protein structures or genome size and conformation. The present discussion’s advantages would extend far beyond an application in CC—from filtration setups to demobilization by nanoparticles to modeling virus fate and persistence in nature.

Modulation of the activation of Statl by the interferon-gamma receptor complex

The activation of Statl by the interferon-gamma （IFN-γ） receptor complex is responsible for the transcription of a significant portion of IFN-γ induced genes. Many of these genes are responsible for the induction of an apoptotic state in response to IFN-γ. In the absence of Stat 1 activation, IFN-γ instead induces a proliferative response. Modifying Stat 1 activation by IFN-γ may have pharmacological benefits. We report that the rate of activation of Statl can be altered in HeLa cells by overexpressing either the IFN-γ R1 chain or the IFN-γ R2 chain. These alterations occur in hematopoietic cell lines： Raji cells and monocytic cell lines, which have average and above-average IFN-γ R2 surface expression, activate Statl similarly to HeLa cells and HeLa cells overexpressing IFNγR2, respectively. The rapid Statl activation seen in HeLa cells can be inhibited by overexpressing a chimeric IFN-γR2 chain that does not bind Jak2 or （when high concentrations of IFN-γ are used） by overexpressing IFN-γR1. These data are consistent with a model in which the recruitment of additional Jak2 activity to a signaling complex accelerates the rate of Statl activation. We conclude that the rate of activation of Statl in cells by IFN-γ can be modified by regulating either receptor chain and speculate that pharmacological agents which modify receptor chain expression may alter IFN-γ receptor signal transduction.

Characterization of a Novel 1Ay Gene and Its Expression Protein in Triticum urartu

High molecular weight glutenin subunit （HMW-GS） plays an important role in determining dough property and breadmaking quality, and the exploration of novel genes for HMW-GS will be crucial for quality improvement program. A gene coding the y type HMW-GS at Glu-A1 locus in Triticum urartu （AA, 2n=2×= 14） with an electrophoretic mobility similar to that of 1Dyl2, was cloned, sequenced, and heterologously expressed. This novel active lay gene FJ404595 was confirmed by structure analyses of nucleotide and deduced amino acid sequences combining with phylogenetic analysis. The open reading frame （ORF） of this gene was 1 830 bp, encoded a protein of 608 amino acid residues containing 46 hexapeptides and 14 nonapeptides, which was mostly similar to the lAy gene AM183223 at a high identity of 99.62% with the two substitutions of both leucine/proline and valine/glutamate, obviously different from the lAy gene EU984504 with 587 residues containing 44 hexapeptides and 13 nonapeptides in T. urartu. The amino acid （leucine） at 446 differed from that （proline） of all the eight compared active lAy subunits. The predicted secondary protein structure implied that this lAy subunit might also have positive impact on flour processing quality.

Application of a new SPA-SVM coupling method for QSPR study of electrophoretic mobilities of some organic and inorganic compounds

In this work, two chemometrics methods are applied for the modeling and prediction of electrophoretic mobilities of some organic and inorganic compounds. The successive projection algorithm, feature selection （SPA） strategy, is used as the descriptor selection and model development method. Then, the support vector machine （SVM） and multiple linear regression （MLR） model are utilized to construct the non-linear and linear quantitative structure-property relationship models. The results obtained using the SVM model are compared with those obtained using MLR reveal that the SVM model is of much better predictive value than the MLR one. The root-mean-square errors for the training set and the test set for the SVM model were 0.1911 and 0.2569, respectively, while by the MLR model, they were 0.4908 and 0.6494, respectively. The results show that the SVM model drastically enhances the ability of prediction in QSPR studies and is superior to the MLR model.

Surface modification of titanium dioxide for electrophoretic particles

To prepare stable electrophoretic ink(E Ink)needs color particles to be uniformly dispersed in the organic medium.Thus,t-he modification of inorganic particle surface is required.In this paper,Titanium dioxide modified by alumina has been studied.The surface composition and struc-tures of modified particles have been characterized by X-ray photoelectron spectrometer(XPS),X-ray diffractometer(XRD)and Fourier transform infrared spectrometer(FT-IR).The dispersibility and electrophoretic mobility of these particles in tetrachloroethylene(TCE)have been investigated by laser particle size analyzer,static sedimentation and elec-trophoretic instrument.Effects of temperature,pH value and stirring rate on the dispersibility and the charge property of samples have been discussed.The results indicate the settle time of modified TiO2 can last 120 h with the response time of 35 s under the optimized modifying conditions,in which temperature is 85℃-90℃,pH is 8-9 and stirring rate is 800 r·min^(−1).The dispersibility and electrophoretic mobility have been significantly improved,which means that the modified TiO2 is suitable for electrophoretic ink particles.

Decline in the expression of IL-2 after trauma and changes in the nuclear transcription factors NFAT and AP-1

OBJECTIVE: To investigate whether the decrease in expression of interleukin-2 (IL-2) after trauma is associated with changes in DNA binding activity of nuclear factor of activated T cells (NFAT) and activator protein-1 (AP-1). METHODS: Mice with closed impact injury with fracture in both hind limbs were adopted as the trauma model. Spleen lymphocytes were isolated from traumatized mice and stimulated with Con-A. Culture supernatants were assayed for IL-2 activity, and total RNA was extracted from spleen lymphocytes and assayed for IL-2 mRNA. DNA binding activity of NFAT and AP-1 were measured by electrophoretic mobility shift assay (EMSA). The expression of c-Fos, c-Jun and JunB proteins was determined by the Western blot analysis. RESULTS: DNA binding activity of NFAT and AP-1 gradually decreased to a minimum of 41% and 49%, respectively, of the control on the 4th day after injury, which was closely followed by the decline in IL-2 activity and IL-2 mRNA. A decrease in the expression of c-Fos on the 1st and 4th day after trauma had no significant effect on c-Jun expression; the increase in expression of JunB was only on the 1st day after injury. CONCLUSION: Decreased IL-2 expression is, at least in part, due to a decline in the activation of NFAT and AP-1 in traumatized mice. The decline in DNA binding activity of NFAT and AP-1 is partly due to a trauma-induced block in the expression of c-Fos.

Polymorphisms and functions of the aldose reductase gene 5' regulatory region in Chinese patients with type 2 diabetes mellitus

OBJECTIVE: To screen the 5' regulatory region of the aldose reductase (AR) gene for genetic variabilities causing changes in protein expression and affecting the promoter function. METHODS: The screenings were carried out by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). All SSCP variants were submitted for DNA sequencing and inserted into the plasmid chloromycetin acetyl transferase (CAT) enhancer vector. The constructs were used to transfect Hela cells, and CAT assays were performed to assess promoter activity. Gel mobility shift and footprinting assays were also performed to determine the interaction between the DNA and nuclear proteins. RESULTS: Two polymorphisms, C (-106) T and C (-12) G, were identified in the regulatory region in 123 Chinese control subjects and 145 patients with type 2 diabetes mellitus. The frequencies of genotypes WT/WT, WT/C (-12) G and WT/C (-106) T were not significantly different between the subjects and patients. In the patients with and without retinopathy, frequencies of WT/C (-106) T were 31.5% and 17.5% (P 0.05) respectively. The total frequency of WT/C (-12) G and WT/C (-106) T in patients with retinopathy was 41.8%, significantly higher than that (20.0%) in patients without retinopathy (P

Structure and Function of N-Terminal Zinc Finger Domain of SARS-CoV-2 NSP2

SARS-CoV-2 has become a global pandemic threatening human health and safety.It is urgent to find effective therapeutic agents and targets with the continuous emergence of novel mutant strains.The knowledge of the molecular basis and pathogenesis of SARS-CoV-2 in host cells requires to be understood comprehensively.The unknown structure and function of nsp2 have hindered our understanding of its role in SARS-CoV-2 infection.Here,we report the crystal structure of the N-terminal of SARS-CoV-2 nsp2 to a high resolution of 1.96?.This novel structure contains three zinc fingers,belonging to the C2 H2,C4,and C2 HC types,respectively.Structure analysis suggests that nsp2 may be involved in binding nucleic acids and regulating intracellular signaling pathways.The binding to single or double-stranded nucleic acids was mainly through the large positively charged region on the surface of nsp2,and K111,K112,K113 were key residues.Our findings lay the foundation for a better understanding of the relationship between structure and function for nsp2.It is helpful to make full use of nsp2 as further research and development of antiviral targets and drug design.

Differently synthesized gold nanoparticles respond differently to functionalization with L-amino acids

The potential utility of gold nanoparticles(AuNPs)synthesized via different methods for biomedical applications vary greatly due to inherent differences in their surface properties.In the present study,we investigated the functionalization of AuNPs synthesized by chemical reduction,plant extract,and bacteria-mediated methods with 22 L-amino acids.Nanoparticles produced by bacteria-mediated(B_AuNPs)and plant-mediated(P_AuNPs)methods showed good potential,as they were able to be functionalized with six(histidine,lysine,methionine,phenylalanine,tryptophan,and tyrosine)and four(cystine,tryptophan,tyrosine,and valine)amino acids,respectively.In contrast,AuNPs produced by chemical reduction(C_AuNPs)were not found to be suitable for functionalization.Optimal functionalization conditions were found to be amino acid concentration of 20-25 mM and neutral pH(7)for P_AuNPs,whereas B_AuNPs tolerated more variable conditions.The electrophoretic mobility of P_AuNPs after functionalization indicated that these nanoparticles were less sensitive than B_AuNPs to the deviations from optimal conditions.A significant change in mobility was observed when B_AuNPs were functionalized with either methionine or tryptophan.Overall,the results of this study suggest that the suitability of the three differently synthesized AuNPs with amino acids is in the following order:B_AuNPs>P_AuNPs>C_AuNPs.