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Gyawali CP, Savarino E, Lazarescu A, Bor S, Patel A, Dickman R, Pressman A, Drewes AM, Rosen J, Drug V, Saps M, Novais L, Vazquez-Roque M, Pohl D, van Tilburg MAL, Smout A, Yoon S, Pandolfino J, Farrugia G, Barbara G, Roman S. Curriculum for neurogastroenterology and motility training: A report from the joint ANMS-ESNM task force. Neurogastroenterol Motil 2018; 30:e13341. [PMID: 29577508 DOI: 10.1111/nmo.13341] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 02/18/2018] [Indexed: 01/10/2023]
Abstract
Although neurogastroenterology and motility (NGM) disorders are some of the most frequent disorders encountered by practicing gastroenterologists, a structured competency-based training curriculum developed by NGM experts is lacking. The American Neurogastroenterology and Motility Society (ANMS) and the European Society of Neurogastroenterology and Motility (ESNM) jointly evaluated the components of NGM training in North America and Europe. Eleven training domains were identified within NGM, consisting of functional gastrointestinal disorders, visceral hypersensitivity and pain pathways, motor disorders within anatomic areas (esophagus, stomach, small bowel and colon, anorectum), mucosal disorders (gastro-esophageal reflux disease, other mucosal disorders), consequences of systemic disease, consequences of therapy (surgery, endoscopic intervention, medications, other therapy), and transition of pediatric patients into adult practice. A 3-tiered training curriculum covering these domains is proposed here and endorsed by all NGM societies. Tier 1 NGM knowledge and training is expected of all gastroenterology trainees and practicing gastroenterologists. Tier 2 knowledge and training is appropriate for trainees who anticipate NGM disorder management and NGM function test interpretation being an important part of their careers, which may require competency assessment and credentialing of test interpretation skills. Tier 3 knowledge and training is undertaken by trainees interested in a dedicated NGM career and may be restricted to specific domains within the broad NGM field. The joint ANMS and ESNM task force anticipates that the NGM curriculum will streamline NGM training in North America and Europe and will lead to better identification of centers of excellence where Tier 2 and Tier 3 training can be accomplished.
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Rosen J, Blau T, Grau SJ, Barbe MT, Fink GR, Galldiks N. Extracranial Metastases of a Cerebral Glioblastoma: A Case Report and Review of the Literature. Case Rep Oncol 2018; 11:591-600. [PMID: 30283316 PMCID: PMC6167720 DOI: 10.1159/000492111] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 07/15/2018] [Indexed: 01/09/2023] Open
Abstract
The glioblastoma, a malignant human brain tumor, is known for its devastating intracranial progress and its dismal prognosis. Whereas treatment and research are most prominently focused on the primary tumor lesion, in recent years evidence has accumulated that points to the rare occurrence of extracranial glioblastoma metastases. We here present a case of a female patient with a known glioblastoma who was detected to harbor multiple metastases in the bones, lung, pleura, liver, mesentery, and the subcutaneous soft tissue. Pathogenetically, these metastatic lesions developed most probably after a local progression of the left temporal glioblastoma through the skull base, thus getting access to the systemic lymphatics. Similar cases of extensive glioblastoma metastization, their putative underlying mechanisms, and implications for clinical care are discussed.
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Rosen J. Enabling high value care in common paediatric gastrointestinal disorders. Int J Clin Pract 2018; 72:e13206. [PMID: 29924469 DOI: 10.1111/ijcp.13206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Nattkemper L, Rosen J, Sanders K, Andersent H, Hsiang J, Bernigaud C, Guillot J, Chosidow O, Yosipovitch G. 460 Non-histaminergic itch mediators elevated in the skin of human scabies patients and a porcine model of scabies. J Invest Dermatol 2018. [DOI: 10.1016/j.jid.2018.03.467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Wong J, Dang L, Le T, Phan N, James S, Katona P, Vu N, Vu T, Katona L, Rosen J, Nguyen C. Strengthening Health System - Evidence from the use of Bi-directional
SMS-based Screening and Feedback System to Improve Efficiency and Quality of
Disease Surveillance in Vietnam. Ann Glob Health 2017. [DOI: 10.1016/j.aogh.2017.03.270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Turk M, Rosen J. The emergence of psychosis in a patient with severe hypothyroidism: A case report and literature review. Eur Psychiatry 2017. [DOI: 10.1016/j.eurpsy.2017.01.1662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Hypothyroidism is associated with changes in mental state that can range from mild cognitive impairment to depression to florid myxedema coma. A few cases have linked the occurence of psychotic symptoms in the context of severe hypothyroidism, an event referred in the literature as “myxedema madness”. We describe the case of a 48-year-old male with no past psychiatric history and a past medical history of hypertension and hypothyroidism who presented to the psychiatric unit for management of new-onset psychosis, particularly paranoid delusions. On basic medical screening, the patient was found to have severe hypothyroidism manifested by a TSH level of 51.85 and a free T4 level less than 0.4. The patient was treated with both an antipsychotic and thyroid hormone replacement, after which his hypothyroid symptoms and his psychosis improved. Liothyronine was also prescribed to speed up the recovery course, as his delusions were thought to be due to his hypothyroidism. The aim of this poster is to shed light on the possibility of development of psychosis concomitantly with severe hypothyroidism, given the rarity of such events, as well as to illustrate the importance of treating the underlying medical cause rather than only focusing on the treatment of the psychiatric symptoms. The use of Liothyronine proved to be beneficial in this case, as the patient's symptoms drastically improved after its administration. This could potentially illustrate the importance of using Liothyronine particularly in the treatment of delusional disorder in severe hypothyroidism.Disclosure of interestThe authors have not supplied their declaration of competing interest.
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Gombas D, Luo Y, Brennan J, Shergill G, Petran R, Walsh R, Hau H, Khurana K, Zomorodi B, Rosen J, Varley R, Deng K. Guidelines To Validate Control of Cross-Contamination during Washing of Fresh-Cut Leafy Vegetables. J Food Prot 2017; 80:312-330. [PMID: 28221982 DOI: 10.4315/0362-028x.jfp-16-258] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The U.S. Food and Drug Administration requires food processors to implement and validate processes that will result in significantly minimizing or preventing the occurrence of hazards that are reasonably foreseeable in food production. During production of fresh-cut leafy vegetables, microbial contamination that may be present on the product can spread throughout the production batch when the product is washed, thus increasing the risk of illnesses. The use of antimicrobials in the wash water is a critical step in preventing such water-mediated cross-contamination; however, many factors can affect antimicrobial efficacy in the production of fresh-cut leafy vegetables, and the procedures for validating this key preventive control have not been articulated. Producers may consider three options for validating antimicrobial washing as a preventive control for cross-contamination. Option 1 involves the use of a surrogate for the microbial hazard and the demonstration that cross-contamination is prevented by the antimicrobial wash. Option 2 involves the use of antimicrobial sensors and the demonstration that a critical antimicrobial level is maintained during worst-case operating conditions. Option 3 validates the placement of the sensors in the processing equipment with the demonstration that a critical antimicrobial level is maintained at all locations, regardless of operating conditions. These validation options developed for fresh-cut leafy vegetables may serve as examples for validating processes that prevent cross-contamination during washing of other fresh produce commodities.
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Fashandi H, Lai CC, Dahlqvist M, Lu J, Rosen J, Hultman L, Greczynski G, Andersson M, Lloyd Spetz A, Eklund P. Ti2Au2C and Ti3Au2C2 formed by solid state reaction of gold with Ti2AlC and Ti3AlC2. Chem Commun (Camb) 2017; 53:9554-9557. [DOI: 10.1039/c7cc04701k] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ti2Au2C and Ti3Au2C2 formation by Au/Ti2AlC and Au/Ti3AlC2 exchange-reactions imply thermodynamic guidelines for identifying materials where these reactions may occur.
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Thore A, Rosen J. An investigation of the in-plane chemically ordered atomic laminates (Mo2/3Sc1/3)2AlC and (Mo2/3Y1/3)2AlC from first principles. Phys Chem Chem Phys 2017; 19:21595-21603. [DOI: 10.1039/c7cp03228e] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have calculated electronic, vibrational, and elastic properties of (Mo2/3Sc1/3)2AlC and (Mo2/3Y1/3)2AlC, two recently discovered nanolaminated materials in the family of so-called i-MAX phases.
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Ingason AS, Dahlqvist M, Rosen J. Magnetic MAX phases from theory and experiments; a review. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:433003. [PMID: 27602484 DOI: 10.1088/0953-8984/28/43/433003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This review presents MAX phases (M is a transition metal, A an A-group element, X is C or N), known for their unique combination of ceramic/metallic properties, as a recently uncovered family of novel magnetic nanolaminates. The first created magnetic MAX phases were predicted through evaluation of phase stability using density functional theory, and subsequently synthesized as heteroepitaxial thin films. All magnetic MAX phases reported to date, in bulk or thin film form, are based on Cr and/or Mn, and they include (Cr,Mn)2AlC, (Cr,Mn)2GeC, (Cr,Mn)2GaC, (Mo,Mn)2GaC, (V,Mn)3GaC2, Cr2AlC, Cr2GeC and Mn2GaC. A variety of magnetic properties have been found, such as ferromagnetic response well above room temperature and structural changes linked to magnetic anisotropy. In this paper, theoretical as well as experimental work performed on these materials to date is critically reviewed, in terms of methods used, results acquired, and conclusions drawn. Open questions concerning magnetic characteristics are discussed, and an outlook focused on new materials, superstructures, property tailoring and further synthesis and characterization is presented.
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Rosen J. The Subduction Zone Observatory takes shape. Science 2016; 353:1347-1348. [DOI: 10.1126/science.353.6306.1347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Wagner G, Rosen J, Holguin G, Frishberg B, Wang A, Sahagian G, Haase-Alasantro L. A-25Clinical Assessment of Posterior Cortical Atrophy. Arch Clin Neuropsychol 2016. [DOI: 10.1093/arclin/acw043.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Westmoreland SV, Rosen J, MacKey J, Romsey C, Xia DL, Visvesvera GS, Mansfield KG. Necrotizing Meningoencephalitis and Pneumonitis in a Simian Immunodeficiency Virus—infected Rhesus Macaque due to Acanthamoeba. Vet Pathol 2016; 41:398-404. [PMID: 15232140 DOI: 10.1354/vp.41-4-398] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Free-living amoebae of the genus Acanthamoeba can cause a fatal disease of the brain in humans called granulomatous amoebic encephalitis. We present a case of meningoencephalitis and pneumonitis in a simian immunodeficiency virus (SIV)-infected rhesus macaque caused by Acanthamoeba sp. The animal became ill 176 days after intravenous inoculation with SIVmac251 after a short history of weight loss and a sudden onset of hind limb paresis and abnormal head movements. Histopathologic examination of hematoxylin and eosin-stained tissues revealed multifocal to coalescing necrotizing neutrophilic meningoencephalitis and pneumonitis. Immunofluorescence and polymerase chain reaction were used to identify the genus of amoeba as Acanthamoeba. Immunohistochemistry of immune cell markers was used to characterize the animal's immune response to the opportunistic amoebic infection with features of both innate and adaptive cell-mediated immunity. Although not previously reported, the potential transmission to humans, either through environmental contamination or contact with an infected animal, makes this disease a threat to laboratory animal care staff and pathologists.
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Thore A, Dahlqvist M, Alling B, Rosen J. Phase stability of the nanolaminates V2Ga2C and (Mo1-xVx)2Ga2C from first-principles calculations. Phys Chem Chem Phys 2016; 18:12682-8. [PMID: 27094754 PMCID: PMC5066482 DOI: 10.1039/c6cp00802j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We here use first-principles calculations to investigate the phase stability of the hypothetical laminated material V2Ga2C and the related alloy (Mo1–xVx)2Ga2C, the latter for a potential parent material for synthesis of (Mo1–xVx)2C, a new two-dimensional material in the family of so called MXenes.
We here use first-principles calculations to investigate the phase stability of the hypothetical laminated material V2Ga2C and the related alloy (Mo1–xVx)2Ga2C, the latter for a potential parent material for synthesis of (Mo1–xVx)2C, a new two-dimensional material in the family of so called MXenes. We predict that V2Ga2C is thermodynamically stable with respect to all identified competing phases in the ternary V–Ga–C phase diagram. We further calculate the stability of ordered and disordered configurations of Mo and V in (Mo1–xVx)2Ga2C and predict that ordered (Mo1–xVx)2Ga2C for x ≤ 0.25 is stable, with an order–disorder transition temperature of ∼1000 K. Furthermore, (Mo1–xVx)2Ga2C for x = 0.5 and x ≥ 0.75 is suggested to be stable, but only for disordered Mo–V configurations, and only at elevated temperatures. We have also investigated the electronic and elastic properties of V2Ga2C; the calculated bulk, shear, and Young's modulus are 141, 94, and 230 GPa, respectively.
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Pabst M, Braganza O, Dannenberg H, Hu W, Pothmann L, Rosen J, Mody I, van Loo K, Deisseroth K, Becker AJ, Schoch S, Beck H. Astrocyte Intermediaries of Septal Cholinergic Modulation in the Hippocampus. Neuron 2016; 90:853-65. [PMID: 27161528 DOI: 10.1016/j.neuron.2016.04.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 07/09/2015] [Accepted: 03/14/2016] [Indexed: 01/17/2023]
Abstract
The neurotransmitter acetylcholine, derived from the medial septum/diagonal band of Broca complex, has been accorded an important role in hippocampal learning and memory processes. However, the precise mechanisms whereby acetylcholine released from septohippocampal cholinergic neurons acts to modulate hippocampal microcircuits remain unknown. Here, we show that acetylcholine release from cholinergic septohippocampal projections causes a long-lasting GABAergic inhibition of hippocampal dentate granule cells in vivo and in vitro. This inhibition is caused by cholinergic activation of hilar astrocytes, which provide glutamatergic excitation of hilar inhibitory interneurons. These results demonstrate that acetylcholine release can cause slow inhibition of principal neuronal activity via astrocyte intermediaries.
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Yango P, Smith J, Altman E, Logan P, Rosen J, Tran N. Suppression of the aberrantly activated TNFA-NFKB pathway in the testicular niche of patients with nonobstructive azoospermia (NOA) restores spermatogonial stem cell self-renewal and expansion. Fertil Steril 2015. [DOI: 10.1016/j.fertnstert.2015.07.113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Alling B, Högberg H, Armiento R, Rosen J, Hultman L. A theoretical investigation of mixing thermodynamics, age-hardening potential, and electronic structure of ternary M(1)1-x M(2)xB2 alloys with AlB2 type structure. Sci Rep 2015; 5:9888. [PMID: 25970763 PMCID: PMC4429488 DOI: 10.1038/srep09888] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 03/19/2015] [Indexed: 11/24/2022] Open
Abstract
Transition metal diborides are ceramic materials with potential applications as hard protective thin films and electrical contact materials. We investigate the possibility to obtain age hardening through isostructural clustering, including spinodal decomposition, or ordering-induced precipitation in ternary diboride alloys. By means of first-principles mixing thermodynamics calculations, 45 ternary M11–xM2xB2 alloys comprising MiB2 (Mi = Mg, Al, Sc, Y, Ti, Zr, Hf, V, Nb, Ta) with AlB2 type structure are studied. In particular Al1–xTixB2 is found to be of interest for coherent isostructural decomposition with a strong driving force for phase separation, while having almost concentration independent a and c lattice parameters. The results are explained by revealing the nature of the electronic structure in these alloys, and in particular, the origin of the pseudogap at EF in TiB2, ZrB2, and HfB2.
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Dahlqvist M, Alling B, Rosen J. A critical evaluation of GGA + U modeling for atomic, electronic and magnetic structure of Cr2AlC, Cr2GaC and Cr2GeC. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:095601. [PMID: 25671459 DOI: 10.1088/0953-8984/27/9/095601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work we critically evaluate methods for treating electron correlation effects in multicomponent carbides using a GGA + U framework, addressing doubts from previous works on the usability of density functional theory in the design of magnetic MAX phases. We have studied the influence of the Hubbard U-parameter, applied to Cr 3d orbitals, on the calculated lattice parameters, magnetic moments, magnetic order, bulk modulus and electronic density of states of Cr2AlC, Cr2GaC and Cr2GeC. By considering non-, ferro-, and five different antiferromagnetic spin configurations, we show the importance of including a broad range of magnetic orders in the search for MAX phases with finite magnetic moments in the ground state. We show that when electron correlation is treated on the level of the generalized gradient approximation (U = 0 eV), the magnetic ground state of Cr2AC (A = Al, Ga, Ge) is in-plane antiferromagnetic with finite Cr local moments, and calculated lattice parameters and bulk modulus close to experimentally reported values. By comparing GGA and GGA + U results with experimental data we find that using a U-value larger than 1 eV results in structural parameters deviating strongly from experimentally observed values. Comparisons are also done with hybrid functional calculations (HSE06) resulting in an exchange splitting larger than what is obtained for a U-value of 2 eV. Our results suggest caution and that investigations need to involve several different magnetic orders before lack of magnetism in calculations are blamed on the exchange-correlation approximations in this class of magnetic MAX phases.
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Hu C, Lai CC, Tao Q, Lu J, Halim J, Sun L, Zhang J, Yang J, Anasori B, Wang J, Sakka Y, Hultman L, Eklund P, Rosen J, Barsoum MW. Mo2Ga2C: a new ternary nanolaminated carbide. Chem Commun (Camb) 2015; 51:6560-3. [DOI: 10.1039/c5cc00980d] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the discovery of a new hexagonal Mo2Ga2C phase, wherein two Ga layers – instead of one – are stacked in a simple hexagonal arrangement in between Mo2C layers.
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Ingason AS, Mockute A, Dahlqvist M, Magnus F, Olafsson S, Arnalds UB, Alling B, Abrikosov IA, Hjörvarsson B, Persson POÅ, Rosen J. Magnetic self-organized atomic laminate from first principles and thin film synthesis. PHYSICAL REVIEW LETTERS 2013; 110:195502. [PMID: 23705717 DOI: 10.1103/physrevlett.110.195502] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Indexed: 06/02/2023]
Abstract
The first experimental realization of a magnetic M(n+1)AX(n) (MAX) phase, (Cr(0.75)Mn(0.25))(2)GeC, is presented, synthesized as a heteroepitaxial single crystal thin film, exhibiting excellent structural quality. This self-organized atomic laminate is based on the well-known Cr(2)GeC, with Mn, a new element in MAX phase research, substituting Cr. The compound was predicted using first-principles calculations, from which a variety of magnetic behavior is envisaged, depending on the Mn concentration and Cr/Mn atomic configuration within the sublattice. The analyzed thin films display a magnetic signal at room temperature.
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Zhan M, Li F, Zhu Y, Ma J, Landua J, Wei W, Vadakkan T, Zhang M, Dickinson M, Lewis M, Rosen J, Wong S. Abstract P4-02-08: Quantitative Characterization of 3D Vasculature Spatial Patterns Within Tumor Microenvironment of Breast Cancer Stem Cells. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p4-02-08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The sustainment characters of cancer stem cells (CSCs) such as self-renew and differentiation to other tumor cells greatly depend on the tumor microenvironment, which is composed of many components, e.g. vasculature, extracellular matrix, epithelial cells, stromal cells, as well as nutrients and oxygen. As vasculature is an important factor for the CSC and tumor development, the understanding of their spatial patterns is essential for calibrating the CSC-microenvironment interactions in mathematical modeling. In this study, we acquired the vasculature in side tumors and normal breast tissues by using two-photon fluorescence microscopy, which enables 3D in vivo imaging. We developed an advanced vasculature segmentation approach for an objective and accurate quantification of the vasculature in 3D image volumes. The approach integrates supervoxel analysis and the orientation guided hidden Markov random field (ori-HMRF) modeling together to compensate for low quality images, e.g., low signal-to-noise ratio (SNR) and uneven background. By constructing a new feature space that combines the CIELAB color space and the coordinates space, the supervoxel analysis divides an image volume into subregions with local similar intensity and restricted regular shape, boundaries of which can delineate the vasculature boundaries accurately even in low intensity contrast regions. We further designed a set of features for the separation of blood vessel regions from the background. To make use of the context information, i.e. the continuity of vasculature, the ori-HMRF model is used to incorporate the consistency of vasculatures' orientation in order to reduce the false positives and negatives. Experimental results on image volumes from both breast cancer and normal breast tissues show that the proposed method can effectively reconstruct the vasculature structure with the CSC embedded tumor microenvironment.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-02-08.
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Wei W, Tweardy D, Zhang M, Roarty K, Rosen J, Lewis M. Abstract P5-03-08: A fluorescence STAT3 reporter preferentially expressed in human breast cancer tumor-initiating cells. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p5-03-08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Cancer initiating/stem cells are thought to be responsible for treatment-resistance, disease-recurrence and metastasis. Current breast cancer stem cell markers lack direct correlation with stem cell function, which makes the targeted therapeutic design difficult. The STAT3 pathway is a critical regulator of the function of normal stem cells and evidence is accumulating for its important role in breast cancer stem cells, as well as associated “niche” cells. However, due to lack of method for pathway-activity-based live cell separation, whether STAT3 functions in the cancer stem cells themselves or in surrounding niche cells, or both remains unknown. To answer this question, we have constructed lentiviral fluorescent reporters, which enables FACS-sorting of cells differ in STAT3 activity as well as in vivo/in situ localization of STAT3 responsive cells. Our study for the first time separated the STAT3 positive and STAT3 negative cells from the same breast tumor in live, and for the first time provided functional evidences that the STAT3 positive cells are enriched for breast cancer stem cells compared to STAT3 negative cells, as tumor cells positive for reporter activity perform better in both mammosphere formation and dilution transplantation assays compared to the negatives.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-03-08.
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Wei W, Zhang M, Tweardy D, Rosen J, Lewis M. PD08-05: Stat3 Signaling in Human Breast Cancer Stem Cells. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-pd08-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Recent data suggest the existence of a unique subset of breast cancer cells capable of initiating tumor growth and giving rise to all other cells characteristic of a given tumor. These cells have been termed “cancer stem cells” or “tumor-initiating cells”. Breast cancer stem cells appear to be resistant to chemo- and radiotherapies and may be responsible for recurrence and metastasis in breast cancer patients. Identifying the cellular signaling pathways responsible for breast cancer stem cell maintenance and self-renewal represents a critical hurdle for developing effective therapeutics. The Stat3 pathway is a critical regulator of the function of normal stem cells, and shows altered expression in human breast cancers [4]. Moreover, IL-6, the Stat3 signaling agonist, is required for breast cancer stem cell function in human breast cancer cell lines. All these suggest an important role of Stat3 signaling in breast cancer stem cells. However, due to lack of method for pathway-activity-based live cell separation, whether Stat3 functions in the cancer stem cells themselves or whether it may function in surrounding niche cells remain unknown. We have constructed a lentiviral fluorescent reporter for Stat3 signaling which contains four copies of M67 Stat3 binding sites upstream of enhanced Green Fluorescent Protein. This reporter system enables FACS-sorting of cells with active Stat3 signaling and in vivo/in situ localization of Stat3 responsive cells. In addition, C188-9, the first Stat3 specific competitive inhibitor, has been developed in our collaborator's lab, which provides us an advanced tool in studying Stat3 function.
We hypothesize that Stat3 signaling is preferentially active in stemlike subpopulation and depend on non-stem cancer cells to maintain its activation. Three aims to test this hypothesis include: 1. To test whether cancer cells with activated Stat3 signaling are enriched for breast cancer stem cells or whether they may serve as niche cells. 2. To test whether small molecule antagonists of Stat3 signaling can inhibit cancer stem cell function. 3. To identify novel targets of Stat3 signaling that may serve as indicators of responsiveness to Stat3 antagonist or predict treatment response.
So far, our GFP reporters for Stat3 signaling effectively report Stat3 activity in both patient xenografts and human breast cancer cell lines in vivo and in vitro, which enables effective separation of Stat3+/Stat3- cells for functional Study. MDA231 and SUM159 tumors with reporters have been established. Tumor cells will be sorted according to Stat3 activity and perform limiting dilution and MSFE assays. Tumors with reporters will also be treated by C188-9, Chemo, or in combination to study synergistic effect of Stat3 inhibitors on tumor growth. Preliminary data based on inhibitor and limiting dilution studies suggested that Stat3 signaling is required for stem cell function. However, neither Stat3+ nor Stat3- cells are self-sufficient in performing these functions, indicating communications between subpopulations.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD08-05.
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Visbal A, Visbal A, Villanueva H, Villanueva H, Rosen J, Rosen J, Lewis M, Lewis M, Lewis M. The Role of Smoothened in Mammary Gland Development and Breast Cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-2164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The hedgehog (Hh) signaling pathway is a critical pathway for development and is known to influence proliferation, cell fate, morphogenesis, and stem cell self-renewal. Mutations activating Hh signaling have been found in a wide variety of cancers, and it is estimated that up to 25% of all tumors display misregulated Hh signaling. Smoothened (Smo), a seven pass transmembrane protein is the Hh signaling pathway's primary effector and its sole non-redundant member. In a recent study, Smo was found to be over-expressed in 70% of ductal carcinom in-situ (DCIS) lesions and 30% of invasive breast carcinomas (IBC). Despite the implication of this protein in breast cancer, little is known about its role in normal mammary gland development.In order to understand the role of Smo in mammary gland development we have performed phenotypic analyses of a conditional mouse model expressing constitutively activated Smo under the control of a mammary gland selective Cre recombinase. We show that activation of the Hh pathway results in increased proliferation starting around five weeks of age that leads to a dramatic increase in branching and budding of the mammary gland at around ten weeks of age. In addition, immunostaining using the ductal markers Na-K-Cl Co-transporter 1 (NKCC1) and aquaporin 5 (AQP5) suggests alterations in cell fate. Finally, these mice exhibit changes in the stroma surrounding the mammary ducts including an increase in collagen deposition. Gene profiling studies show upregulation of several genes, including targets of the Notch pathway, in ten-week-old virgin mammary glands from the constitutively active conditional Smo mouse model when compared to control. Surprisingly, canonical downstream Hh target genes like Patched and Gli were not found to be upregulated. These data in conjunction with recent published studies suggest that Smo activation in the mammary gland may be acting via a non-canonical mechanism to produce the observed hyper-branched and budded phenotype. Preliminary studies indicate that Smoothened may be functioning as a G-protein coupled receptor (GPCR) via a pertussis-toxin sensitive mechanism. Interestingly, constituitive Smo activity does not appear to alter cyclic AMP (cAMP) levels as recently reported in Drosophila indicating that mammalian Smo may be acting via a different mechanism.In addition to these gain-of-function studies, experiments are underway utilizing a conditional null Smo mouse model (loss-of-function) to determine if there is a requirement for Hh pathway activation in normal mammary gland development. Preliminary analysis indicates that partial loss of Smo in mammary gland cells leads to impaired ductal elongation and reduced branching.Future studies will include the generation of mammary gland chimeras to study the possible paracrine interactions between Smo over-expressing and wild type cells. Additionally, experiments are under way to elucidate the mechanism of Smo's GPCR function in the mammary gland.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2164.
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Jin G, Zhou X, Lewis M, Rosen J, Wong S. Signal-Transduction Based Network Biomarkers for Tumor-Initiating Cells in a p53-Null Mouse Model of Breast Cancer. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-2138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction: Tumor initiating cells (TICs), or cancer stem cells, have the capacity to self-renew, and are likely to be responsible for resistance to conventional therapies, disease recurrence, and metastasis. Known TIC biomarkers may allow us to understand which genes are critical to self-renewal of TICs. However, little is known about how these biomarkers manipulate other molecules to enable TICs to self-renew. Here, we develop a systems biology approach to identify the signal-transduction network biomarkers for understanding the mechanisms in the renewal of TICs.Methods: Comparing with conventional biomarker discovery, the network biomarkers are identified by not only differential genes but also protein-protein interaction (PPI) network and available signaling pathways. Depending on the interacting patterns in PPI network and their associated cellular processes in signaling pathways, we can reveal the key signal transductions or subnetworks responsible for self-renewal of TICs. We chose two types of enriched interacting patterns, i.e. triangle and spoon, to indicate the signal transductions around the single biomarkers. A published RNA microarray (GSE8863) was performed on mammary epithelial cells from p53-null tumors sorted by two stem cell markers CD29 and CD24. The differential genes were identified by the Fold-Changes (FCs) comparing the subpopulations of Lin —CD29HCD24H with other subpopulations. Gene Set Enrichment Analysis (GSEA) revealed that the identified differential genes are significantly enriched in 20 regulatory pathways including 'Cell cycle', 'Adherens junction', 'Cell adhesion molecules (CAMs)', 'Tight junction' (P<10-3). A model called Multiple Objective Optimization (MOO) was employed to search the network biomarkers whose component proteins satisfy that (1) be most differentially expressed in Lin —CD29HCD24H cells and (2) pass through a large number of enriched signaling pathways.Results: Four genes (Lsm5, Calm3, Bmi1 and Ezh2) are extremely up-regulated in the Lin —CD29HCD24H subpopulations (FC>4), in which Bmi1 is important in regulating the self-renewal capacity of hematopoietic, as well as human mammary gland stem cells. To understand how these genes manipulate other genes and the enriched signaling pathways, we first analyzed the interacting patterns around these genes. Calm3 and Bmi1 are surrounded by 355 and 22 interacting patterns respectively. The component coding-genes in the interacting patterns are more likely to be differentially expressed (91/127, P <10-61). Then, the protein-paths were identified from the interacting patterns of Calm3 and Bmi1 by MOO. IPA (Ingenuity Pathway Analysis) indicated that these protein paths have many particular cellular functions related to self-renewal, such as 'Cell Growth and Proliferation', 'Hematological System Development and Function', 'Cell-To-Cell Signaling and Interaction', and 'Cell Death' (P <10-3).Conclusion: The network biomarkers revealed that the surrounding interaction patterns and related signaling pathways of single biomarkers are essential to understand the signal-transduction mechanisms of TICs in self-renewal. They may be useful as prognostic or predictive indicators as well as suggest possible targets for novel therapies.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2138.
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