In the past Hua Shen has collaborated on articles with Tong-Yi Zhang and Susan M. Twine. One of their most recent publications is Conference set no. 1 fundamentals of recrystallizationThe influence of cohesive forces on the equilibrium concentration of hydrogen atoms ahead of a crack tip in single crystal iron. Which was published in journal Scripta Metallurgica et Materialia.

More information about Hua Shen research including statistics on their citations can be found on their Copernicus Academic profile page.

Hua Shen's Articles: (27)

In vivo proteomic analysis of the intracellular bacterial pathogen, Francisella tularensis, isolated from mouse spleen

AbstractUnderstanding the pathogenesis of infectious diseases requires comprehensive knowledge of the proteins expressed by the pathogen during in vivo growth in the host. Proteomics provides the tools for such analyses but the protocols required to purify sufficient quantities of the pathogen from the host organism are currently lacking. Here, we present a rapid immunomagnetic protocol for the separation of Francisella tularensis, a highly virulent bacterium and potential biowarfare agent, from the spleens of infected mice. In less than one hour, bacteria can be isolated in quantities sufficient to carry out meaningful proteomic comparisons with in vitro grown bacteria. Furthermore, the isolates are virtually free from contaminating host proteins. Two-dimensional gel analysis revealed a host induced proteome in which 78 proteins were differentially expressed in comparison to in vitro grown controls. The results obtained clearly demonstrate the complexity of the adaptive response of F. tularensis to the host environment, and the difficulty of mimicking such behavior in vitro.

Research reportInvolvement of phosphatidylinositol 3-kinase and insulin-like growth factor-I in YXLST-mediated neuroprotection

AbstractIn the present study, we examine the neuroprotective role of the external Qi of YXLST in cultured retinal neurons. Primary retinal neuronal cultures were grown from retinas of 0–2-day-old Sprague–Dawley rats. Cultures were treated directly with external Qi of YXLST 30 min prior to H2O2 exposure in most experiments. Cell viability was measured by 3,(4,5-dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide (MTT) assay. Apoptotic cell death was evaluated by the TdT-mediated digoxigenin-dUTP nick-end labeling TUNEL assay, and by DNA laddering analysis. Northern blot analysis was performed to examine the level of insulin-like growth factor-I (IGF-I) gene expression. Phosphatidylinositol 3-kinase (PI3K) assay was performed to study the PI3K activity. The results showed that treatment of external Qi of YXLST significantly attenuated neuronal death that was induced by 24-h exposure to hydrogen peroxide, and greatly inhibited hydrogen peroxide-induced apoptosis. External Qi of YXLST also upregulated IGF-I gene expression and increased PI3K activity. These observations indicate that external Qi-mediated IGF-I expression and PI3K signaling could be one of the mechanisms in neuroprotection by YXLST.

Regular ArticleChicken Transcription Factor AP-2: Cloning, Expression and Its Role in Outgrowth of Facial Prominences and Limb Buds

AbstractEmbryonic facial development in chick embryos involves a sequential activation of genes that control differential growth and patterning of the beak. In the present study we isolate one such gene, the transcription factor, AP-2, that is known to be expressed in the face of mouse embryos. The protein sequence of chick AP-2α is 94% homologous to human and mouse AP-2. Wholemountin situhybridization with a probe for chick AP-2 identifies expression from primitive streak stages up to stage 28. The most striking expression patterns in the head are during neural crest cell migration when AP-2 transcripts follow closely the tracts previously mapped for neural crest cells. Later, expression in the facial mesenchyme is strongest in the frontonasal mass and lateral nasal prominences and is downregulated in the maxillary and mandibular prominences. Once limb buds are visible, high expression is seen in the distal mesenchyme but not in the apical ectodermal ridge. The expression patterns of AP-2 in stage 20 embryos suggested that the gene may be important in “budding out” of facial prominences and limb buds. We implanted beads soaked in retinoic acid in the right nasal pit of stage 20 embryos resulting in a specific inhibition of outgrowth of the frontonasal mass and lateral nasal prominences. AP-2 expression was completely down-regulated in the lateral nasal within 8 hr of bead application. In addition, the normal up-regulation of AP-2 in the frontonasal mass did not occur following retinoic-acid treatment. There was an increase in programmed cell death around the right nasal pit that accompanied the down-regulation of AP-2. Prominences whose morphogenesis were not affected by retinoic acid did not have altered expression patterns. We removed the apical ectodermal ridge in stage 20 limb buds and found that AP-2 expression was partially downregulated 4 hr following ridge removal and completely downregulated 8 hr following stripping. Application of an FGF-4 soaked bead to the apex of the limb bud maintained AP-2 expression. Thus AP-2 is involved in outgrowth and could be regulated by factors such as FGFs that are present in the ectoderm of both the face and limb.

Maximum-principle-satisfying space-time conservation element and solution element scheme applied to compressible multifluids

AbstractA maximum-principle-satisfying space-time conservation element and solution element (CE/SE) scheme is constructed to solve a reduced five-equation model coupled with the stiffened equation of state for compressible multifluids. We first derive a sufficient condition for CE/SE schemes to satisfy maximum-principle when solving a general conservation law. And then we introduce a slope limiter to ensure the sufficient condition which is applicative for both central and upwind CE/SE schemes. Finally, we implement the upwind maximum-principle-satisfying CE/SE scheme to solve the volume-fraction-based five-equation model for compressible multifluids. Several numerical examples are carried out to carefully examine the accuracy, efficiency, conservativeness and maximum-principle-satisfying property of the proposed approach.

Analysis of laser M2 determination in a quadriwave lateral shearing interferometer with CCD vertical blooming

Highlights•The mechanism responsible for the influence of CCD vertical blooming on the M2 measurement in a QWLSI is analyzed.•The relationship between the M2 and the degree of CCD vertical blooming in a QWLSI is revealed.•The influence of the blooming in a QWLSI on the M2 can be ignored by improving the exposure time of the CCD camera.•The M2 in the direction where the blooming is located is more sensitive to the blooming streak than in other directions.

Stable carbon and oxygen isotopic composition of modern land snails along a precipitation gradient in the mid-latitude East Asian monsoon region of China

Highlights•Climatic significance of stable isotopes in snail shells is evaluated along a precipitation gradient.•Shell δ13C is a reliable precipitation proxy.•Shell δ18O values are influenced by precipitation δ18O, temperature and evaporation processes.

Full Length ArticleRisk and benefit of direct oral anticoagulants or PAR-1 antagonists in addition to antiplatelet therapy in patients with acute coronary syndrome

Highlights•The value of triple antithrombotic therapy in ACS was evaluated.•Triple therapy had an up to 3-fold increased risk of intracranial hemorrhage.•Triple therapy did not improve net clinical outcome.

Simplified design of elastoplastic structures with metallic yielding dampers based on the concept of uniform damping ratio

Highlights•Uniform damping ratio design concept is raised for structure with metallic dampers.•Dampers are expected to have the same damping ratio under certain dynamic excitations.•Stiffness and damping parameters of metallic dampers can be designed individually.•Design procedure can be simplified with a demand-oriented design scheme based on UDR.•Elastoplastic properties of both the structure and dampers are considered.

Original articleGenomic alterations in lung adenocarcinomas detected by multicolor fluorescence in situ hybridization and comparative genomic hybridization

AbstractWe used two molecular cytogenetic techniques, multicolor fluorescence in situ hybridization (M-FISH) and comparative genomic hybridization (CGH), to analyze three established lung adenocarcinoma cell lines (A549, H1650, and SPC-A-1) and primary lung adenocarcinoma samples, to identify common chromosomal aberrations. M-FISH revealed numerous complex chromosomal rearrangements. Chromosomes 5, 6, 11, 12, and 17 were most frequently involved in interchromosomal translocations. CGH revealed regions on 1q, 2p, 3q, 5p, 5q, 7p, 8q, 11q, 12q, 14q, 16p, 17p, 19q, 20q, 21q, and 22q to be commonly overrepresented and regions on 2q, 3p, 4p, 5q, 7q, 8p, 9p, 13q, 14q, and 17p to be underrepresented. The most common gains were found in 16p13 (in 50% of samples), and 16p13 amplification was associated with relatively poor differentiation and late stage. M-FISH and CGH can be a powerful tool in identification of genomic alterations in lung cancer, as well as in diagnosis. The overrepresented regions may harbor potential candidate genes involved in lung adenocarcinoma pathogenesis.

Mice vaccinated with the O-antigen of Francisella tularensis LVS lipopolysaccharide conjugated to bovine serum albumin develop varying degrees of protective immunity against systemic or aerosol challenge with virulent type A and type B strains of the pathogen

AbstractThe purpose of this study was to evaluate the efficacy of a vaccine consisting of the O-polysaccharide of the lipopolysaccharide (LPS) of Francisella tularensis chemically conjugated to bovine serum albumin. The results show that conjugation preserved both the antigenicity and immunogenicity of the polysaccharide moiety. Mice vaccinated with the glyco-conjugate, but not with BSA alone, were completely protected against an intradermal challenge with a highly virulent type B strain of F. tularensis, and partially protected against an aerosol challenge with the same strain. However, such vaccination failed to protect against an aerosol challenge with a virulent type A strain of the pathogen. The results suggest that the O-antigen of F. tularensis could be considered as a potential component of a subunit vaccine against type B, but not type A strains of F. tularensis.

A design method of viscoelastic damper parameters based on the elastic-plastic response reduction curve

Highlights•EPRRC based elastoplastic design is developed for structure with viscoelastic damper.•Response control effect can be overestimated by traditional ERRC method.•Parameters of viscoelastic dampers can be obtained directly using the proposed method.

Night-time total electron content enhancements at equatorial anomaly region in China

AbstractThis paper presents small scale (duration ⩽1 h, ΔTEC ⩾ 1TECU) night-time total electron content (TEC) enhancements observed at the equatorial anomaly region in China, for the first time. The data is from a GPS receiver chain established in 2005 by Institute of Center for Space Science and Applied Research, Chinese Academy of Sciences and a GPS receiver of International GPS Service (IGS), located between Fuzhou (26.1°N, 119.3°E) and Nanning (22.8°N, 108.3°E). Two other GPS observations of IGS taken at higher latitude were also used to investigate the localization of such phenomenon. The characteristics of the night-time TEC enhancement are examined with two case studies. The TEC increases about 1–3TECU, intermittently. While the night-time TEC enhancement mainly occurs at the equatorial anomaly region, it can be observed at middle latitude as well. The spatial size of the enhancement region is less than 5° in longitude. The primary statistical study shows that the TEC enhancement is more often observed in spring and autumn, but rarely in summer. It has no dependence on geomagnetic activity. The enhancement can occur both before and after midnight.

Response of the Total Electron Content of Terrestrial Ionosphere to GRB041227☆☆☆

AbstractAt 21:30 UT on 2004 December 27 an extremely strong gamma-ray burst swept across the earth and caused the part of the terrestrial upper atmosphere exposed to it to produce extra ionization. Sudden ionospheric disturbance (SID) events were simultaneously observed at many of the very low frequency (VLF) electric wave observing stations. Analyses of the X-ray data of the GOES satellite as well as the solar wind and interplanetary data of the ACE satellite with the relevant theories show that the observed SID event observed was indeed caused by GRB041227. We calculated the response of the total electron content (TEC) of the terrestrial ionosphere to this γ-ray burst using the observed data provided by the international GPS service network (IGS) and the data processing method of coherent summation. The result indicates that the GRB041227 produced by the SGR1806-20 had an evident effect on the terrestrial ionosphere: in the course of the burst the average ionospheric TEC increased, to a maximum size of about 0.04 TECU (1 TECU = 1016 el/m2), equivalent to a solar flare with importance of C or lower. The calculated result demonstrates once again that a remote celestial body can also affect the terrestrial space environment to some extent.

Differential expression of peroxiredoxin 6 in fetal rat testis following in utero exposure to di(nbutyl) phthalate

AbstractObjectivesTo isolate and identify differentially expressed proteins in fetal rat testis following in utero exposure to di(nbutyl) phthalate (DBP).MethodsWe used the technique of proteomic analysis to compare the testis protein patterns obtained by two-dimensional gel electrophoresis from fetal rats of gestation day 19.ResultsWe found significant differences in protein spot intensities. Subsequently several of these variant protein spots were identified by mass spectrometry. Peroxiredoxin 6 (Prdx6) was one of them. Prdx6, which expressed a higher level in DBP-treated fetal rat testes compared with normal ones, is a member of the peroxiredoxins family (Prdxs). Recently, Prdx6 had been shown to be important in protecting cells from oxidative injury. Further, immunohistochemical analyses of fetal rat testes sections were made to determine the cellular distribution of this protein, consequently a strong Prdx6 staining was found out primarily in Leydig cells.ConclusionsThe present study had found several differentially regulated proteins and demonstrated the differential expression of Prdx6 in fetal rat testis following in utero exposure to DBP, when compared with controls. Combining the cellular location of Prdx6 and its function in other tissues, the results of this study could provide us with a possibility to interfere the reproductive toxicity of DBP for its specific antioxidant properties in testis tissues.

Original articleMulticolor fluorescence in situ hybridization and comparative genomic hybridization reveal molecular events in lung adenocarcinomas and squamous cell lung carcinomas

AbstractWe have used the molecular cytogenetic techniques of multicolor fluorescence in situ hybridization (M-FISH) and comparative genomic hybridization (CGH) to analyze two established lung cancer cell lines (A549, H520), 80 primary lung adenocarcinoma samples and 80 squamous cell lung carcinoma samples in order to identify common chromosomal aberrations. M-FISH revealed numerous complex chromosomal rearrangements. Chromosomes 5, 6, 11, 12, and 17 were most frequently involved in interchromosomal translocations. CGH revealed regions on 1q, 2p, 3q, 5p, 5q, 7p, 8q, 11q, 12q, 14q, 16p, 17p, 19q, 20q, 21q and 22q to be commonly over-represented and regions on 2q, 3p, 4p, 5q, 7q, 8p, 9p, 13q, 14q, and 17p to be under-represented. In lung adenocarcinomas the most common gains were found in 16p13 (50%); while in squamous cell lung carcinomas the common gains were found in 17q21 (45%) and these alterations were observed to be associated with their specific pathological subtype. In conclusion, the present study contributes to the molecular biological characterization in lung adenocarcinomas and squamous cell lung carcinomas and through evaluation of molecular events to the recently emergent focus on novel markers for lung cancer treatment.

Original articleInvolvement of mTOR and survivin inhibition in tamoxifen-induced apoptosis in human hepatoblastoma cell line HepG2

AbstractPatients with advanced hepatocellular carcinoma (HCC) have shown to benefit from tamoxifen treatment. The mechanisms of tamoxifen effects in HCC, however, are not yet clearly understood. The PI3K/Akt/mTOR signal pathway is involved in cell proliferation, tumorigenesis, and apoptosis. Over-expression of survivin has played an important role in leading to antiapoptosis. The current study investigated changes in mTOR pathway and survivin expression in hepatocarcinoma cell line HepG2 treated with tamoxifen. We detected apoptosis of hepatocarcinoma cells by flow cytometry assay. Survivin transcription level and p70S6k was demonstrated by PCR, dual-luciferase reporter assay and western blot analysis respectively. Our results are showed as follows: tamoxifen leads to apoptosis of the cells, and reduction in survivin expression, as well as a dramatic reduction in the activated form of p70S6 kinase. Twenty micromoles tamoxifen treatment signifcantly depresses transcription of survivin mRNA. Treating HepG2 cells with rapamycin, a specific mTOR inhibitor, significantly reduce survivin protein level but did not affect survivin transcription, which indicated that tamoxifen and rapamycin were synergistic in regards to down-regulation of survivin expression in hepatocellular carcinoma cells. Our results suggest that tamoxifen down-regulate survivin expression in HepG2 cells is mediated by transcriptional and posttranscriptional level via PI3K/Akt/mTOR pathway to induce apoptosis.

Short communicationVirulence comparison in mice of distinct isolates of type A Francisella tularensis

AbstractFrancisella tularensis subspecies tularensis (type A F. tularensis) is considered to be one of the most virulent of all bacterial pathogens. Mice are extremely susceptible to infection with this subspecies (LD100 via various inoculation routes is <10 cfu). However, it has not been established whether overt virulence differences exist amongst type A strains of F. tularensis. To this end, the present study compared the virulence of two distinct type A strains, FSC033 and SCHU S4, for naïve mice and mice immunized with the live vaccine strain of the pathogen, F. tularensis LVS. One nominal isolate of SCHU S4 was found to be completely avirulent. Another isolate was highly virulent, but all examined cases appeared somewhat less virulent than FSC033. The implication of these findings for future infection and immunity studies is discussed.

Sensitive, real-time PCR detects low-levels of contamination by Legionella pneumophila in commercial reagents

AbstractIn a real-time PCR assay of Legionella pneumophila (targeting the L. pneumophila-specific mip gene and using SYBR Green dye for DNA detection in conjunction with the iCycler system) we detected as few as 1.3 copies of a mip gene in a 50-μl reaction from serially diluted L. pneumophila genomic DNA. However, cycle threshold (CT) were yielded and DNA product detected in our no-template negative controls and the phenomenon persisted when two separate batches of PCR reagents and water from two different biochemical companies were tested. Since L. pneumophila can be widespread in municipal water supplies, the commercial reagents, especially the reagent water (80% of the reaction volume), could be the source of contamination. To test this hypothesis, we treated Millipore Milli-Q water by filtering through a 0.2 μm-pore-size polycarbonate filter to remove bacteria prior to autoclaving. Real-time PCR using this water had no contamination. Our finding is indirect evidence that commercially available purified water can harbor low level contamination by L. pneumophila DNA that has escaped purification processes. This presents a challenge when developing a sensitive DNA-based bacterial detection method if the target organism or its DNA is a common contaminant of necessary reagents.

Gene expression patternCloning, expression, and alternative splicing of neogenin1 in zebrafish

AbstractCaenorhabditis elegans UNC-40, Drosophila Frazzled, and vertebrate Neogenin and DCC constitute a subgroup of the immunoglobulin superfamily (IgSF). They possess four immunoglobulin-like domains and six fibronectin-type III repeats at the extracellular region, a single transmembrane region, and a ∼300 amino-acid intracellular region. UNC-40, Frazzled and DCC can function in axon guidance as the receptor of Netrin (Cell Mol. Life Sci. 56 (1999) 62; Curr. Opin. Cell Biol. 10 (1998) 609). Neogenin binds to Netrin-1 with the same affinity as DCC in vitro (Cell 87 (1996) 175), and is expressed by neurons as they project axons (J. Cell Biol. 127 (1994) 2009), suggesting that it is also a DCC-like Netrin receptor. A zebrafish homologue of DCC (zDCC) is reported recently (Mech. Dev. 109 (2001) 105), but so far there is no report of zebrafish Neogenin. To elucidate a possible neural function of vertebrate Neogenin, we cloned and characterized a zebrafish homologue of neogenin, zneo1, and identified four alternative splice sites within it. In the adult, despite broad tissue distribution, our reverse transcription polymerase chain reaction and Northern analyses demonstrated the dominant expression of zneo1 mRNA in brain. We detected zneo1 mRNA in the embryos from 10 hpf onward and revealed its spatiotemporally regulated expression pattern in both neuronal and non-neuronal tissues by in situ hybridization. Our data showed that during early brain development, zneo1 mRNA was not only present in the proliferative ventricular zones but also in the domains of several first postmitotic neuron clusters when they extended axons. Alternative splicing generates several isoforms of zneo1. Most of them are developmentally regulated, showing distinct distribution in brain and other tissues.

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