345 research outputs found

    Author Correction: LKB1 loss links serine metabolism to DNA methylation and tumorigenesis

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    Erratum for: LKB1 loss links serine metabolism to DNA methylation and tumorigenesis. [Nature. 2016

    Inhibitor-Sensitive FGFR1 Amplification in Human Non-Small Cell Lung Cancer

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    Background Squamous cell lung carcinomas account for approximately 25% of new lung carcinoma cases and 40,000 deaths per year in the United States. Although there are multiple genomically targeted therapies for lung adenocarcinoma, none has yet been reported in squamous cell lung carcinoma. Methodology/Principal Findings Using SNP array analysis, we found that a region of chromosome segment 8p11-12 containing three genes–WHSC1L1, LETM2, and FGFR1–is amplified in 3% of lung adenocarcinomas and 21% of squamous cell lung carcinomas. Furthermore, we demonstrated that a non-small cell lung carcinoma cell line harboring focal amplification of FGFR1 is dependent on FGFR1 activity for cell growth, as treatment of this cell line either with FGFR1-specific shRNAs or with FGFR small molecule enzymatic inhibitors leads to cell growth inhibition. Conclusions/Significance These studies show that FGFR1 amplification is common in squamous cell lung cancer, and that FGFR1 may represent a promising therapeutic target in non-small cell lung cancer.Novartis Pharmaceuticals CorporationAmerican Lung AssociationUniting Against Lung CancerSara Thomas Monopoli FundSeaman FoundationIndia. Dept. of BiotechnologyNational Lung Cancer Partnershi

    \u3cem\u3eLkb1\u3c/em\u3e Inactivation Drives Lung Cancer Lineage Switching Governed by Polycomb Repressive Complex 2

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    Adenosquamous lung tumours, which are extremely poor prognosis, may result from cellular plasticity. Here, we demonstrate lineage switching of KRAS+ lung adenocarcinomas (ADC) to squamous cell carcinoma (SCC) through deletion of Lkb1 (Stk11) in autochthonous and transplant models. Chromatin analysis reveals loss of H3K27me3 and gain of H3K27ac and H3K4me3 at squamous lineage genes, including Sox2, ΔNp63 and Ngfr. SCC lesions have higher levels of the H3K27 methyltransferase EZH2 than the ADC lesions, but there is a clear lack of the essential Polycomb Repressive Complex 2 (PRC2) subunit EED in the SCC lesions. The pattern of high EZH2, but low H3K27me3 mark, is also prevalent in human lung SCC and SCC regions within ADSCC tumours. Using FACS-isolated populations, we demonstrate that bronchioalveolar stem cells and club cells are the likely cells-of-origin for SCC transitioned tumours. These findings shed light on the epigenetics and cellular origins of lineage-specific lung tumours

    Процесс анализа угроз, влияющих на экономическую устойчивость предприятия

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    На основании проведенного исследования были выявлены факторы возникновения угроз, их группировка по степени воздействию на экономическую устойчивость предприятий и рассмотрена формализация процесса анализа угроз экономической устойчивости предприятий. В условиях рыночной экономики невозможно управлять предприятием без учета влияния угроз, а для эффективного управления важно не только знать об их присутствии, а и правильно идентифицировать конкретную угрозу.На підставі проведеного дослідження були виявлені чинники виникнення загроз, їх угруповання по степені впливу на економічну стійкість підприємств і розглянута формалізація процесу аналізу загроз економічної стійкості підприємств. В умовах ринкової економіки неможливо керувати підприємством без вивчення впливу загроз, а для ефективного керування важливо не тільки знати про їх присутність, а і правильно ідентифікувати конкретну загрозу.On the basis of the conducted research the factors of origin of threats were exposed, their gourmet on a degree to influence on economic stability of enterprises and formalization of process of analysis of threats of economic stability of enterprises is considered. In the conditions of market economy it is impossible to manage an enterprise without taking into account influencing of threats, and for the effective management it is important not only to know about their presence, and to identify the concrete threat correctly

    Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand

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    [EN] Currently in the USA, one name is added to the organ transplant waiting list every 15 min. As this list grows rapidly, fewer than one-third of waiting patients can receive matched organs from donors. Unfortunately, many patients who require a transplant have to wait for long periods of time, and many of them die before receiving the desired organ. In the USA alone, over 100,000 patients are waiting for a kidney transplant. However, it is a problem that affects around 6% of the word population. Therefore, seeking alternative solutions to this problem is an urgent work. Here, we review the current promising regenerative technologies for kidney function replacement. Despite many approaches being applied in the different ways outlined in this work, obtaining an organ capable of performing complex functions such as osmoregulation, excretion or hormone synthesis is still a long-term goal. However, in the future, the efforts in these areas may eliminate the long waiting list for kidney transplants, providing a definitive solution for patients with end-stage renal disease.This study was supported by a grant from ALCER-TURIA, ASTELLAS and PRECIPITA CROWDFUNDING.Garcia-Dominguez, X.; Vicente Antón, JS.; Vera Donoso, CD.; Marco-Jiménez, F. (2017). Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand. Current Urology Reports. 18(1):1-8. https://doi.org/10.1007/s11934-017-0650-6S18181Ott HC, Mathisen DJ. Bioartificial tissues and organs: are we ready to translate? Lancet. 2011;378:1977–8.Salvatori M, Peloso A, Katari R, Orlando G. Regeneration and bioengineering of the kidney: current status and future challenges. Curr Urol Rep. 2014;15:379.D’Agati VD. Growing new kidneys from embryonic cell suspensions: fantasy or reality? J Am Soc Nephrol. 2002;11:1763–6.Abouna GM. Organ shortage crisis: problems and possible solutions. 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J Biol Chem. 2014;289:4594–9.Freedman BS, Brooks CR, Lam AQ, Fu H, Morizane R, Agrawal V, et al. Modelling kidney disease with CRISPR-mutant kidney organoids derived from human pluripotent epiblast spheroids. Nat Commun. 2015;6:8715.Hu J, Lei Y, Wong WK, Liu S, Lee KC, He X, et al. Direct activation of human and mouse Oct4 genes using engineered TALE and Cas9 transcription factors. Nucleic Acids Res. 2014;42:4375–90.Den Hartogh SC, Schreurs C, Monshouwer-Kloots JJ, Davis RP, Elliott DA, Mummery CL, et al. Dual reporter MESP1 mCherry/w-NKX2-5 eGFP/w hESCs enable studying early human cardiac differentiation. Stem Cells. 2015;33:56–67.Fukui A, Yokoo T. Kidney regeneration using developing xenoembryo. Curr Opin Organ Transplant. 2015;20:160–4.Chen J, Lansford R, Stewart V, Young F, Alt FW. RAG-2-deficient blastocyst complementation: an assay of gene function in lymphocyte development. Proc Natl Acad Sci U S A. 1993;90:4528–32.Ueno H, Turnbull BB, Weissman IL. Two-step oligoclonal development of male germ cells. Proc Natl Acad Sci U S A. 2009;106:175–80.Fraidenraich D, Stillwell E, Romero E, Wilkes D, Manova K, Basson CT, et al. Rescue of cardiac defects in id knockout embryos by injection of embryonic stem cells. Science. 2004;306:247–52.Kobayashi T, Yamaguchi T, Hamanaka S, Kato-Itoh M, Yamazaki Y, Ibata M, et al. Generation of rat pancreas in mouse by interspecific blastocyst injection of pluripotent stem cells. Cell. 2010;142:787–99.Matsunari H, Nagashima H, Watanabe M, Umeyama K, Nakano K, Nagaya M, et al. Blastocyst complementation generates exogenic pancreas in vivo in apancreatic cloned pigs. Proc Natl Acad Sci U S A. 2013;110:4557–62.Espejel S, Roll GR, McLaughlin KJ, Lee AY, Zhang JY, Laird DJ, et al. Induced pluripotent stem cell-derived hepatocytes have the functional and proliferative capabilities needed for liver regeneration in mice. J Clin Invest. 2010;120:3120–6.Usui J, Kobayashi T, Yamaguchi T, Knisely AS, Nishinakamura R, Nakauchi H. Generation of kidney from pluripotent stem cells via blastocyst complementation. Am J Pathol. 2012;180:2417–26.Aggarwal S, Moggio A, Bussolati B. Concise review: stem/progenitor cells for renal tissue repair: current knowledge and perspectives. Stem Cells Transl Med. 2013;2:1011–9.Yokote S, Yokoo T. Organogenesis for kidney regeneration. Curr Opin Organ Transplant. 2013;18:186–90.Crapo PM, Gilbert TW, Badylak SF. An overview of tissue and whole organ decellularization processes. Biomaterials. 2011;32:3233–43.Berthiaume F, Maguire TJ, Yarmush ML. Tissue engineering and regenerative medicine: history, progress, and challenges. Annu Rev Chem Biomol Eng. 2011;2:403–30.Badylak SF. Xenogeneic extracellular matrix as a scaffold for tissue reconstruction. Transpl Immunol. 2004;12:367–77.Badylak SF. The extracellular matrix as a biologic scaffold material. Biomaterials. 2007;28:3587–93.Ott HC, Matthiesen TS, Goh SK, Black LD, Kren SM, Netoff TI, et al. Perfusion-decellularized matrix: using nature’s platform to engineer a bioartificial heart. Nat Med. 2008;14:213–21.Yokoo T. Kidney regeneration with stem cells: an overview. Nephron Exp Nephrol. 2014;126(2):54.Uygun BE, Soto-Gutierrez A, Yagi H, Izamis ML, Guzzardi MA, Shulman C, et al. Organ reengineering through development of a transplantable recellularized liver graft using decellularized liver matrix. Nat Med. 2010;16:814–20.Ott HC, Clippinger B, Conrad C, Schuetz C, Pomerantseva I, Ikonomou L, et al. Regeneration and orthotopic transplantation of a bioartificial lung. Nat Med. 2010;16:927–33.Montserrat N, Garreta E, Izpisua Belmonte JC. Regenerative strategies for kidney engineering. FEBS J. 2016. doi: 10.1111/febs.13704 .Murphy SV, Atala A. 3D bioprinting of tissues and organs. Nat Biotechnol. 2014;32:773–85.Groll J, Boland T, Blunk T, Burdick JA, Cho DW, Dalton PD, et al. Biofabrication: reappraising the definition of an evolving field. Biofabrication. 2016;8:013001.Mandrycky C, Wang Z, Kim K, Kim DH. 3D bioprinting for engineering complex tissues. Biotechnol Adv. 2016;34:422–34.Uzarski JS, Xia Y, Belmonte JC, Wertheim JA. New strategies in kidney regeneration and tissue engineering. Curr Opin Nephrol Hypertens. 2014;23:399–405.Humes HD, Buffington DA, MacKay SM, Funke AJ, Weitzel WF. Replacement of renal function in uremic animals with a tissue-engineered kidney. Nat Biotechnol. 1999;17:451–5.Chevtchik NV, Fedecostante M, Jansen J, Mihajlovic M, Wilmer M, Rüth M, Masereeuw R, Stamatialis D. Upscaling of a living membrane for bioartificial kidney device. Eur J Pharmacol. 2016.Humes HD, Sobota JT, Ding F, Song JH. A selective cytopheretic inhibitory device to treat the immunological dysregulation of acute and chronic renal failure. Blood Purif. 2010;29:183–90.Tumlin J, Wali R, Williams W, Murray P, Tolwani AJ, Vinnikova AK, et al. Efficacy and safety of renal tubule cell therapy for acute renal failure. J Am Soc Nephrol. 2008;19:1034–40.Yokoo T, Ohashi T, Shen JS, Sakurai K, Miyazaki Y, Utsunomiya Y, et al. Human mesenchymal stem cells in rodent whole-embryo culture are reprogrammed to contribute to kidney tissues. Proc Natl Acad Sci U S A. 2005;102(9):3296–300.Yokoo T, Fukui A, Ohashi T, Miyazaki Y, Utsunomiya Y, Kawamura T, et al. Xenobiotic kidney organogenesis from human mesenchymal stem cells using a growing rodent embryo. J Am Soc Nephrol. 2006;17:1026–34.Cooper DK. A brief history of cross-species organ transplantation. Proc (Bayl Univ Med Cent). 2012;25:49–57.Costa MR, Fischer N, Gulich B, Tönjes RR. Comparison of porcine endogenous retroviruses infectious potential in supernatants of producer cells and in cocultures. Xenotransplantation. 2014;21:162–73.Takeda S, Rogers SA, Hammerman MR. Differential origin for endothelial and mesangial cells after transplantation of pig fetal renal primordia into rats. 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They demonstrated the potential of this technique as a possible solution to the kidneys shortage.Yokote S, Yokoo T, Matsumoto K, Utsunomiya Y, Kawamura T, Hosoya T. The effect of metanephroi transplantation on blood pressure in anephric rats with induced acute hypotension. Nephrol Dial Transplant. 2012;27:3449–55.Matsumoto K, Yokoo T, Yokote S, Utsunomiya Y, Ohashi T, Hosoya T. Functional development of a transplanted embryonic kidney: effect of transplantation site. J Nephrol. 2012;25:50–5.Yokote S, Yokoo T, Matsumoto K, Ohkido I, Utsunomiya Y, Kawamura T, et al. Metanephroi transplantation inhibits the progression of vascular calcification in rats with adenine-induced renal failure. Nephron Exp Nephrol. 2012;120:e32–40.Matsumoto K, Yokoo T, Matsunari H, Iwai S, Yokote S, Teratani T, et al. Xeno‐transplanted embryonic kidney provides a niche for endogenous mesenchymal stem cell differentiation into erythropoietin-producing tissue. Stem Cells. 2012;30:1228–35.Abrahamson DR. Glomerular development in intraocular and intrarenal graft of fetal kidney. Lab Investig. 1991;64:629–39.Woolf AS, Palmer SJ, Snow ML, Fine LG. Creation of functioning chimeric mammalian kidney. Kidney Int. 1990;38:991–7.Robert B, St John PL, Hyink DP, Abrahamson DR. Evidence that embryonic kidney cells expressing flk-1 are intrinsic, vasculogenic angioblasts. Am J Physiol. 1996;271:F744–53.Koseki C, Herzlinger D, Al-Awqati Q. Integration of embryonic nephrogenic cells carrying a reporter gene into functioning nephrons. Am J Physiol. 1991;261:C550–4.Rogers SA, Lowell JA, Hammerman NA, Hammerman MR. Transplantation of developing metanephroi into adult rats. Kidney Int. 1998;54:27–37.Barakat TL, Harrison RG. The capacity of fetal and neonatal renal tissues to regenerate and differentiate in a heterotropic allogenic subcutaneous tissue site in the rat. J Anat. 1971;110:393–407.Rogers SA, Liapis H, Hammerman MR. Transplantation of metanephroi across the major histocompatibility complex in rats. Am J Physiol Regul Integr Comp Physiol. 2001;280:R132–6.Vera-Donoso CD, García-Dominguez X, Jiménez-Trigos E, García-Valero L, Vicente JS, Marco-Jiménez F. Laparoscopic transplantation of metanephroi: a first step to kidney xenotransplantation. Actas Urol Esp. 2015;39:527–34.•• Marco-Jiménez F, Garcia-Dominguez X, Jimenez-Trigos E, Vera-Donoso CD, Vicente JS. Vitrification of kidney precursors as a new source for organ transplantation. Cryobiology. 2015;70:278–82. This study found that it is possible to create a long-term biobank of kidney precursors as an unlimited source of organs for transplantation and open new therapeutic possibilities for the patients with chronic renal failure.Garcia-Dominguez X, Vicente JS, Vera-Donoso C, Jimenez-Trigos E, Marco-Jiménez F. First steps towards organ banks: vitrification of renal primordia. 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Cryobiology. 2014;68:294–302

    Place-responsive pedagogy: learning from teachers' experiences of excursions in nature

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    The nature-based excursion has been a significant teaching strategy in environmental education for decades. This article draws upon empirical data from a collaborative research project where teachers were encouraged to visit natural areas to provide an understanding of their roles and experiences of planning and enacting excursions. The analysis indicates that teachers' sensitisation towards 10 place was aided by collaboration, advance planning visits and the very practice of making place-responsive excursions with pupils. The authors build on the analysis to propose a theory of place-responsive pedagogy. At its core, place-responsive pedagogy involves the explicit efforts to teach by means of an environment with the aim of understanding and improving human-environment 15 relations. Some implications for teacher professional development are offered

    Decreased Pre-existing Ad5 Capsid and Ad35 Neutralizing Antibodies Increase HIV-1 Infection Risk in the Step Trial Independent of Vaccination

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    <div><h3>Background</h3><p>The Step trial raised the possibility that uncircumcised men with pre-existing Ad5 neutralizing antibodies carried an increased risk of HIV infection after vaccination. Thus, understanding Ad seropositivity in humans is important to the development of an AIDS vaccine. Here, we analyze the impact of different Ad5-specific neutralizing antibodies on immune function and clinical outcome.</p> <h3>Methods and Findings</h3><p>Ad seropositivity in the Step trial volunteers was analyzed using chimeric rAd5/35 vectors to characterize their specificity for Ad5 fiber and non-fiber external (capsid) proteins. Immune responses and HIV seropositivity were correlated with the specificity of Ad5-neutralizing antibodies. Neutralizing antibodies induced by the vaccine in Ad5 seronegative subjects were directed preferentially to Ad5 capsid proteins, although some fiber-neutralizing antibodies could be detected. Pre-vaccination Ad5 serostatus did not affect the capsid-directed response after three vaccinations. In contrast, anti-fiber antibody titers were significantly higher in volunteers who were Ad5 seropositive prior to vaccination. Those Ad5 seropositive subjects who generated anti-capsid responses showed a marked reduction in vaccine-induced CD8 responses. Unexpectedly, anti-vector immunity differed qualitatively in Ad5 seropositive participants who became HIV-1 infected compared to uninfected case controls; Ad5 seropositive participants who later acquired HIV had lower neutralizing antibodies to capsid. Moreover, Ad35 seropositivity was decreased in HIV-infected subjects compared with uninfected case controls, while seroprevalence for other serotypes including Ad14, Ad28 and Ad41 was similar in both groups.</p> <h3>Conclusions</h3><p>Together, these findings suggest that the case subjects were less immunologically responsive prior to infection. Subjects infected during the Step trial had qualitative differences in immunity that increased their risk of HIV-1 infection independent of vaccination.</p> </div
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