545 research outputs found
Modulation of MicroRNA-194 and cell migration by HER2-targeting trastuzumab in breast cancer
Conceived and designed the experiments: XFL GAC RCB. Performed the
experiments: XFL MIA WM RS MSN SZ. Analyzed the data: XFL SR.
Contributed reagents/materials/analysis tools: YW GAC. Wrote the paper: XFL RCB.Trastuzumab, a humanized monoclonal antibody directed against the extracellular domain of the HER2 oncoprotein, can effectively target HER2-positive breast cancer through several mechanisms. Although the effects of trastuzumab on cancer cell proliferation, angiogenesis and apoptosis have been investigated in depth, the effect of trastuzumab on microRNA (miRNA) has not been extensively studied. We have performed miRNA microarray profiling before and after trastuzumab treatment in SKBr3 and BT474 human breast cancer cells that overexpress HER2. We found that trastuzumab treatment of SKBr3 cells significantly decreased five miRNAs and increased three others, whereas treatment of BT474 cells significantly decreased two miRNAs and increased nine. The only change in miRNA expression observed in both cell lines following trastuzumab treatment was upregulation of miRNA-194 (miR-194) that was further validated in vitro and in vivo. Forced expression of miR-194 in breast cancer cells that overexpress HER2 produced no effect on apoptosis, modest inhibition of proliferation, significant inhibition of cell migration/invasion in vitro and significant inhibition of xenograft growth in vivo. Conversely, knockdown of miR-194 promoted cell migration. Increased miR-194 expression markedly reduced levels of the cytoskeletal protein talin2 and specifically inhibited luciferase reporter activity of a talin2 wild-type 39-untranslated region, but not that of a mutant reporter, indicating that talin2 is a direct downstream target of miR-194. Trastuzumab treatment inhibited breast cancer cell migration and reduced talin2 expression in vitro and in vivo. Knockdown of talin2 inhibited cell migration/invasion. Knockdown of trastuzumab-induced miR-194 expression with a miR-194 inhibitor compromised trastuzumab-inhibited cell migration in HER2-overexpressing breast cancer cells. Consequently, trastuzumab treatment upregulates miR-194 expression and may exert its cell migration-inhibitory effect through miR-194-mediated downregulation of cytoskeleton protein talin2 in HER2-overexpressing human breast cancer cells.This work was supported by the Anne and Henry Zarrow Foundation, kind gifts from Stuart and Gaye Lynn Zarrow and from Mrs. Delores Wilkenfeld, the Laura and John Arnold Foundation, the RGK Foundation, and the MD Anderson NCI CCSG P30 CA16672. G.A.C. is supported as a Fellow at the University of Texas MD Anderson Research Trust, as a University of Texas System Regents Research Scholar and by the CLL Global Research Foundation
g-C3N4/Ti3C2Tx (MXenes) composite with oxidized surface groups for efficient photocatalytic hydrogen evolution
Ti3C2Tx is a 2-dimensional titanium carbide material featuring outstanding electrochemical properties. In spite of this, application of Ti3C2Tx as co-catalyst in photo-catalysis is rarely explored, probably because of its metallic nature and hydrophilic surface. Given that Ti3C2Tx with different surface terminations exhibits large differences in catalytic, electrochemical and chemical properties, we demonstrate an improvement of the photocatalytic activity of Ti3C2Tx as a co-catalyst by annealing a composite of carbon nitride and Ti3C2Tx. Ti3C2Tx with an oxygen terminated surface improved the separation of electron-hole pairs and resulted in a 105% enhancement in the production ratio of hydrogen evolution compared to control samples. The best hydrogen production performance reached as high as 88 μmol h-1 gcat-1. The apparent quantum yield (AQY) reached as high as 1.27%. The DFT calculations also demonstrate a better hydrogen evolution on Ti3C2 with oxygen surface termination
Large-scale Synthesis of β-SiC Nanochains and Their Raman/Photoluminescence Properties
Although the SiC/SiO2 nanochain heterojunction has been synthesized, the chained homogeneous nanostructure of SiC has not been reported before. Herein, the novel β-SiC nanochains are synthesized assisted by the AAO template. The characterized results demonstrate that the nanostructures are constructed by spheres of 25–30 nm and conjoint wires of 15–20 nm in diameters. Raman and photoluminescence measurements are used to explore the unique optical properties. A speed-alternating vapor–solid (SA-VS) growth mechanism is proposed to interpret the formation of this typical nanochains. The achieved nanochains enrich the species of one-dimensional (1D) nanostructures and may hold great potential applications in nanotechnology
Rationales, design and recruitment of the Taizhou Longitudinal Study
<p/> <p>Background</p> <p>Rapid economic growth in China in the past decades has been accompanied by dramatic changes in lifestyle and environmental exposures. The burdens of non-communicable diseases, such as cardiovascular diseases, diabetes and cancer, have also increased substantially.</p> <p>Methods/design</p> <p>We initiated a large prospective cohort–the Taizhou Longitudinal Study–in Taizhou (a medium-size city in China) to explore the environmental and genetic risk factors for common non-communicable diseases. The sample size of the cohort will be at least 100,000 adults aged 30–80 years drawn from the general residents of the districts of Hailin, Gaogang, and Taixing (sample frame, 1.8 million) of Taizhou. A three-stage stratified sampling method will be applied. Baseline investigations include interviewer-administered questionnaire, anthropometric measurements, and collection of buccal mucosal cells and blood specimens. DNA will be extracted for genetic studies and serum samples will be used for biochemical examinations. A follow-up survey will be conducted every three years to obtain information on disease occurrence and information on selected lifestyle exposures. Study participants will be followed-up indefinitely by using a chronic disease register system for morbidity and cause-specific mortality. Information on non-fatal events will be obtained for certain major categories of disease (e.g., cancer, stroke, myocardial infarction) through established registry systems.</p> <p>Discussion</p> <p>The Taizhou Longitudinal Study will provide a good basis for exploring the roles of many important environmental factors (especially those concomitant with the economic transformation in China) for common chronic diseases, solely or via interaction with genetic factors.</p
Advances in small lasers
M.T.H was supported by an Australian Research council Future Fellowship research grant for this work. M.C.G. is grateful to the Scottish Funding Council (via SUPA) for financial support.Small lasers have dimensions or modes sizes close to or smaller than the wavelength of emitted light. In recent years there has been significant progress towards reducing the size and improving the characteristics of these devices. This work has been led primarily by the innovative use of new materials and cavity designs. This Review summarizes some of the latest developments, particularly in metallic and plasmonic lasers, improvements in small dielectric lasers, and the emerging area of small bio-compatible or bio-derived lasers. We examine the different approaches employed to reduce size and how they result in significant differences in the final device, particularly between metal- and dielectric-cavity lasers. We also present potential applications for the various forms of small lasers, and indicate where further developments are required.PostprintPeer reviewe
Antisense oligonucleotides against microRNA-21 reduced the proliferation and migration of human colon carcinoma cells
Cardio-metabolic risk factors and prehypertension in persons without diabetes, hypertension, and cardiovascular disease
10.1186/1471-2458-13-730BMC Public Health131
Crosslinkable potato starch-based graft copolymer emulsion for humidity controlling coatings
Synthesis and Magnetic Properties of Maghemite (γ-Fe2O3) Short-Nanotubes
We report a rational synthesis of maghemite (γ-Fe2O3) short-nanotubes (SNTs) by a convenient hydrothermal method and subsequent annealing process. The structure, shape, and magnetic properties of the SNTs were investigated. Room-temperature and low-temperature magnetic measurements show that the as-fabricated γ-Fe2O3 SNTs are ferromagnetic, and its coercivity is nonzero when the temperature above blocking temperature (TB). The hysteresis loop was operated to show that the magnetic properties of γ-Fe2O3 SNTs are strongly influenced by the morphology of the crystal. The unique magnetic behaviors were interpreted by the competition of the demagnetization energy of quasi-one-dimensional nanostructures and the magnetocrystalline anisotropy energy of particles in SNTs
HIV-Infected Former Plasma Donors in Rural Central China: From Infection to Survival Outcomes, 1985–2008
BACKGROUND: The HIV epidemic among former plasma donors (FPDs) in rural Central China in the early-mid 1990s is likely the largest known HIV-infected cohort in the world related to commercial plasma donation but has never been fully described. The objectives of this study are to estimate the timing and geographic spread of HIV infection in this cohort and to demonstrate the impact of antiretroviral therapy on survival outcomes. METHODOLOGY/PRINCIPAL FINDINGS: HIV-infected FPDs were identified using the national HIV epidemiology and treatment databases. Locations of subjects were mapped. Dates of infection and survival were estimated using the midpoint date between initial-final plasma donation dates from 1985-2008 among those with plasma donation windows ≤2 years. Among 37,084 FPDs in the two databases, 36,110 were included. 95% were located in focal areas of Henan Province and adjacent areas of surrounding provinces. Midpoint year between initial-final plasma donation dates was 1994 among FPDs with known donation dates. Median survival from infection to AIDS was 11.8 years and, among those not treated, 1.6 years from AIDS to death. Among those on treatment, 71% were still alive after five years. Using Cox proportional hazard modeling, untreated AIDS patients were 4.9 times (95% confidence interval 4.6-5.2) more likely to die than those on treatment. CONCLUSIONS/SIGNIFICANCE: The epidemic of HIV-infected FPD in China was not widespread throughout China but rather was centered in Henan Province and the adjacent areas of surrounding provinces. Even in these areas, infections were concentrated in focal locations. Overall, HIV infections in this cohort peaked in 1994, with median survival of 13.4 years from infection to death among those not treated. Among AIDS patients on treatment, 71% were still alive after five years
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