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Carreira A.C.O.,University of Sao Paulo | Zambuzzi W.F.,Paulista University | Rossi M.C.,Paulista University | Filho R.A.,University of Sao Paulo | And 4 more authors.
Vitamins and Hormones

Bone morphogenetic proteins (BMPs), glycoproteins secreted by some cells, are members of the TGF-β superfamily that have been implicated in a wide variety of roles. Currently, about 20 different BMPs have been identified and grouped into subfamilies, according to similarities with respect to their amino acid sequences. It has been shown that BMPs are secreted growth factors involved in mesenchymal stem cell differentiation, also being reported to control the differentiation of cancer stem cells. BMPs initiate signaling from the cell surface by binding to two different receptors (R: Type I and II). The heterodimeric formation of type I R and II R may occur before or after BMP binding, inducing signal transduction pathways through SMADs. BMPs may also signal through SMAD-independent pathways via mitogen-activated protein kinases (ERK, p38MAPKs, JNK). BMPs may act in an autocrine or paracrine manner, being regulated by specific antagonists, namely: noggin and chordin. Genetic engineering allows the production of large amounts of BMPs for clinical use, and clinical trials have shown the benefits of FDA-approved recombinant human BMPs 2 and 7. Several materials from synthetic to natural sources have been tested as BMP carriers, ranging from hydroxyapatite, and organic polymers to collagen. Bioactive membranes doped with BMPs are promising options, acting to accelerate and enhance osteointegration. The development of smart materials, mainly based on biopolymers and bone-like calcium phosphates, appears to provide an attractive alternative for delivering BMPs in an adequately controlled fashion. BMPs have revealed a promising future for the fields of Bioengineering and Regenerative Medicine. In this chapter, we review and discuss the data on BMP structure, mechanisms of action, and possible clinical applications. © 2015 Elsevier Inc. Source

Rodrigues M.F.S.D.,University of Sao Paulo | De Oliveira Rodini C.,University of Sao Paulo | De Aquino Xavier F.C.,Federal University of Bahia | Paiva K.B.,Chemistry Institute | And 7 more authors.
Medicine (United States)

Homeobox genes are a family of transcription factors that play a pivotal role in embryogenesis. Prospero homeobox 1 (PROX1) has been shown to function as a tumor suppressor gene or oncogene in various types of cancer, including oral squamous cell carcinoma (OSCC). We have previously identified PROX1 as a downregulated gene in OSCC. The aim of this study is to clarify the underlying mechanism by which PROX1 regulates tumorigenicity of OSCC cells. PROX1 mRNA and protein expression levels were first investigated in 40 samples of OSCC and in nontumor margins. Methylation and amplification analysis was also performed to assess the epigenetic and genetic mechanisms involved in controlling PROX1 expression. OSCC cell line SCC9 was also transfected to stably express the PROX1 gene. Next, SCC9-PROX1-overexpressing cells and controls were subjected to proliferation, differentiation, apoptosis, migration, and invasion assays in vitro. OSCC samples showed reduced PROX1 expression levels compared with nontumor margins. PROX1 amplification was associated with better overall survival. PROX1 overexpression reduces cell proliferation and downregulates cyclin D1. PROX1-overexpressing cells also exhibited reduced CK18 and CK19 expression and transcriptionally altered the expression of WISP3, GATA3, NOTCH1, and E2F1. Our results suggest that PROX1 functions as a tumor suppressor gene in oral carcinogenesis. Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source

News Article
Site: http://news.mit.edu/topic/mitchemistry-rss.xml

James L. Kinsey, the former head of the Department of Chemistry at MIT and the D. R. Bullard-Welch Foundation Professor of Science Emeritus at Rice University, died unexpectedly on Dec. 20. He was 80. Kinsey was born in Paris, Texas, in 1934. He earned a BA from Rice in 1956 and continued at that institution for graduate studies, earning a PhD in physical chemistry in 1959 under Robert F. Curl, who went on to receive the Nobel Prize in chemistry in 1996. The title of Kinsey’s dissertation was “The Microwave Spectrum of Chlorine Dioxide.” In 1959 and 1960, Kinsey spent one year at the University of Uppsala in Sweden as an NSF Postdoctoral Fellow at the Quantum Chemistry Institute. He then spent a year in the Department of Chemistry at the University of California at Berkeley as a Miller Research Fellow. In 1962, Kinsey was appointed as an assistant professor of chemistry at MIT, where he served for 26 years, rising through the tenure ranks. He succeeded John Deutch, now an Institute Professor, as head of the Department of Chemistry in 1977, and held that position until 1982. “Jim Kinsey mentored me from the time I was a graduate student,” Deutch says. “He tried to teach me group theory and 3j coupling coefficients, but failed. His knowledge and devotion to chemistry was unmatched. Throughout his career, he made great contributions to MIT, Rice, and the Welch Foundation. One of my oldest and trusted friends is gone, and I grieve for the loss.” Kinsey was known for his novel studies of the dynamics of disintegrating molecules using various spectroscopic techniques, including his significant advance of Fourier transform doppler spectroscopy and, with Robert W. Field, the development of stimulated emission pumping. He was also much admired for his leadership skills and his unpretentious disposition. “Jim and I had a wonderful collaboration,” says Field, the Robert T. Haslam and Bradley Dewey Professor of Chemistry. “We were so different in our scientific styles, our relationships with members of our joint research group, and in how we would approach and finish off a problem. … Jim was analytical; I was intuitive. Jim was cautious; I was not. … We created magic between us, and shared the joy of knowing that we had created some new truth.” “Our cross-department collaboration involved two joint PhDs, two [undergraduate researchers], one future Nobel Prize winner, a lot of brown-bag lunches, and the delight of both scientific and personal insights — including that Jim and I shared the same birthday,” says Dave Pritchard, the Cecil and Ida Green Professor of Physics. “I was having lunch with him about a month ago, when — typically — he had to rush off to do something for a former student.” David Jonas PhD '92, a professor of chemistry at the University of Colorado at Boulder, says, “Jim Kinsey was a wonderful co-advisor. I benefited tremendously from his gentle and seemingly effortless approach to resolving contested scientific questions and fondly recall his mischievous sense of humor. I will always remember Jim as a great human being.” Sylvia Ceyer, current head of the Department of Chemistry and the John C. Sheehan Professor of Chemistry, recalls, “Jim was the chemistry department head who hired me as an assistant professor in 1981. From that moment on, Jim became a beloved mentor and friend who selflessly and carefully read and valuably commented on many of my early proposals and papers, even though the subject matter was not centered in his own research interests. I know that I am a much better scientist because of Jim.” She adds, “Jim Kinsey was so incredibly smart, but more importantly, so profoundly wise. He had a knack for quickly spotting the heart of an issue and deftly employing his dry wit to rapidly build a consensus. Listening to the clever repartee of Jim, Bob Silbey, John Deutch, Irwin Oppenheim, and John Waugh is a most cherished MIT memory.” In 1988, Kinsey took early retirement from MIT and returned to Rice, his alma mater, where he served as dean of the Wiess School of Natural Sciences for 10 years. In addition, he served Rice's interim provost from 1993 to 1994. “Jim Kinsey came to Rice with a vision for what we could be, and set about in a determined fashion to bring that view into the reality we see today,” says Kathleen Matthews, who succeeded Kinsey as dean of the Wiess School. “But no discussion of him would ignore his wit and sense of humor.” Kinsey made frequent return visits to MIT while serving as a member of the MIT Chemistry Department Visiting Committee from 1994 to 2006. Kinsey served as chairman of the Scientific Advisory Board of the Robert A. Welch Foundation from 2006 to 2012. He was a member of the National Academy of Sciences and received the E.O. Lawrence Award of the Department of Energy and the Earle K. Plyler Prize of the American Physical Society. He was a fellow of the American Physical Society and of the American Academy of Arts and Sciences. He and Field were honored as mentors of their joint student Yonqin Chen, who received the American Chemical Society’s Nobel Laureate Signature Prize in Graduate Education. There will be a memorial at Rice University in the Keck Lecture Hall (old chemistry lecture hall) on Saturday, Feb. 28, at 2 p.m., with a reception to follow at Brochstein Pavilion.

« SLAC, Utrecht Univ. team visualize poisoning of FCC catalysts used in gasoline production; seeing changes in pore network materials | Main | Eaton’s new Bussmann series EV fuses allow drivers to go further, faster » A US Department of Energy (DOE) program designed to spur the use of high performance supercomputers to advance US manufacturing has funded 13 new industry projects for a total of $3.8 million. Among the projects selected are one by GM and EPRI of California to improve welding techniques for automobile manufacturing and power plant builds in partnership with Oak Ridge National Laboratory (ORNL). Another one of the 13 projects is led by Sepion Technologies, which will partner with LBNL to make new membranes to increase the lifetime of Li-S batteries for hybrid airplanes. The High Performance Computing for Manufacturing (HPC4Mfg) Program creates an ecosystem that allows experts at DOE’s national laboratories to work directly with manufacturing industry members to teach them how to adopt or advance their use of high performance computing (HPC) to address manufacturing challenges with a goal of increasing energy efficiency, reducing environmental impacts and advancing clean energy technologies. The partnerships use world-class supercomputers and scientific expertise from Lawrence Livermore National Laboratory (LLNL), which leads the program, and partner laboratories Lawrence Berkeley and Oak Ridge national laboratories (LBNL and ORNL), which in turn team up with US manufacturers. GM and EPRI. GM and EPRI, representing two major US manufacturing industry sectors (automotive and nuclear energy) and both having welding research & development capabilities, will work with Oak Ridge National Laboratory (ORNL) for the purpose of advancing HPC weld modeling tools for broad industrial applications. This potential will be demonstrated with two representative welded structural components: The goal is to reduce the computational time of the two above examples from days or months to several hours while providing adequate solution accuracy so that the HPC weld modeling tools could effectively optimize welding technology in order to minimize dimensional distortion and proactively mitigate the detrimental impact of weld-induced residual stresses. Sepion. Efforts to commercialize light-weight, energy-dense lithium-sulfur secondary batteries (2510 Wh kg–1) have been stalled by ongoing problems with the battery’s membrane, which limits cycle-life. Sepion’s polymer membrane technology provides a counterpoint, yielding long-lasting lithium-sulfur cells. Advancing to 10 Ah battery prototypes, Sepion faces challenges in membrane manufacturing related to polymer processing and the molecular basis for membrane performance and durability. High-performance computing offers critical new insight into these phenomena, which in turn will accelerate the product’s entry into the market. Sepion envisions that successes could catalyze a transformation in aviation, in which fuel-burning aircraft are replaced with hybrid-electric planes featuring 30–50% reductions in fuel costs and emissions. Shiloh Industries of Ohio will partner with ORNL to study phase change cooling of tooling to speed up casting processes in a project titled “Development of a Transformational Micro-Cooling Technology for High-Pressure Die Casting using High-Performance Computing.” Rolls-Royce Corporation of Indiana will partner with ORNL to improve silicon carbide composites in a project titled “Level-set Modeling Simulations of Chemical Vapor Infiltration for Ceramic Matrix Composites Manufacturing.” ORNL will partner with Agenda 2020 Technology Alliance, a consortium focused on the paper industry to design better catalysts for lignin breakdown in a project titled “Catalytic Pulping of Wood.” LLNL will partner with GE Global Research Center in New York to study how to mitigate defects caused by direct metal laser melting in a project titled “Minimization of Spatter during Direct Metal Laser Melting (DMLM) Additive Manufacturing Process using ALE3D Coupled with Experiments." PPG of Pennsylvania will partner with LBNL to decrease the time needed to paint automobiles in a project titled “Modeling Paint Behavior During Rotary Bell Atomization.” Actasys, Incorporated of New York, will partner with ORNL to decrease the fuel consumption of trucks by actively modifying the flow around the trucks in a project titled “High Performance Computational Modeling of Synthetic Jet Actuators for Increased Freight Efficiency in the Transportation Industry.” Carbon, Incorporated of California will partner with LBNL to increase the speed of polymer additively manufactured components in a project titled “Multi-physics Modeling of Continuous Liquid Interface Production (CLIP) for Additive Manufacturing.” The American Chemical Society Green Chemistry Institute will partner with LBNL to develop lower energy mechanisms of chemical separation using membranes in a project titled “Accelerating Industrial Application of Energy-Efficient Alternative Separations.” The Alzeta Corporation of California will partner with LBNL to destroy effluents from semiconductor processing that could potentially harm the ozone layer in a project titled “Improving Gas Reactor Design With Complex Non-Standard Reaction Mechanisms in a Reactive Flow Model.” Applied Materials, Incorporated will partner with LLNL to enable the manufacture of higher quality, more efficient LEDs for lighting in a project titled “Modeling High Impulse Magnetron Sputtering (HiPIMS) plasma sources for reactive Physical Vapor Deposition (PVD) processes used in fabrication of high efficiency LEDs.” Harper International Corp. of New York will partner with ORNL to reduce the cost of carbon fibers in a project titled “Development and Validation of Simulation Capability for the High Capacity Production of Carbon Fiber.” The program has previously funded 16 projects ranging from improving turbine blades for aircraft engines to reducing heat loss in electronics to improving fiberglass production. Partners range from small to large companies, industry consortiums and institutes. Although the program is focused on using national lab HPC resources to bolster manufacturing, it is possible that other fields, such as transportation, the modern electrical grid and advanced integrated circuitry also could benefit. As the program broadens, other national laboratory partners are expected to join.

Turan A.Z.,Chemistry Institute | Elbeyli Y.,Chemistry Institute | Kalafatoglu I.E.,Marmara University
Journal of the Electrochemical Society

In the present work, membrane electrolysis of nearly saturated borax solution prepared from borax pentahydrate (Na2B4O 7.5H2O) was studied. Mono layer cation-exchange membrane (Nafion 551) was used as a separator in a two-compartment electrolysis cell for the production of sodium hydroxide and boric acid. The anolyte concentration was adjusted in order to obtain a Na2O/B2O3 mol ratio of 0.1 by dissolving boric acid and borax pentahydrate together. Experiments were performed in continuous operation mode by feeding nearly saturated borax solution. The effects of different catholyte concentrations (10, 20, and 30% NaOH) on the current efficiency and the specific energy consumption were calculated and the quality of boric acid products was determined. © 2012 The Electrochemical Society. All right reserved. Source

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