Role of Caveolin 1, E-Cadherin, Enolase 2 and PKCalpha on resistance to methotrexate in human HT29 colon cancer cells

<p>Abstract</p> <p>Background</p> <p>Methotrexate is one of the earliest cytotoxic drugs used in cancer therapy, and despite the isolation of multiple other folate antagonists, methotrexate maintains its significant role as a treatment for different types of cancer and other disorders. The usefulness of treatment with methotrexate is limited by the development of drug resistance, which may be acquired through different ways. To get insights into the mechanisms associated with drug resistance and sensitization we performed a functional analysis of genes deregulated in methotrexate resistant cells, either due to its co-amplification with the <it>dhfr </it>gene or as a result of a transcriptome screening using microarrays.</p> <p>Methods</p> <p>Gene expression levels were compared between triplicate samples from either HT29 sensitive cells and resistant to 10^-5M MTX by hybridization to the GeneChip^®HG U133 PLUS 2.0 from Affymetrix. After normalization, a list of 3-fold differentially expressed genes with a p-value < 0.05 including multiple testing correction (Benjamini and Hochberg false discovery rate) was generated. RT-Real-time PCR was used to validate the expression levels of selected genes and copy-number was determined by qPCR. Functional validations were performed either by siRNAs or by transfection of an expression plasmid.</p> <p>Results</p> <p>Genes adjacent to the <it>dhfr locus </it>and included in the 5q14 amplicon were overexpressed in HT29 MTX-resistant cells. Treatment with siRNAs against those genes caused a slight reduction in cell viability in both HT29 sensitive and resistant cells. On the other hand, microarray analysis of HT29 and HT29 MTX resistant cells unveiled overexpression of caveolin 1, enolase 2 and PKCα genes in resistant cells without concomitant copy number gain. siRNAs against these three genes effectively reduced cell viability and caused a decreased MTX resistance capacity. Moreover, overexpression of E-cadherin, which was found underexpressed in MTX-resistant cells, also sensitized the cells toward the chemotherapeutic agent. Combined treatments targeting siRNA inhibition of caveolin 1 and overexpression of E-cadherin markedly reduced cell viability in both sensitive and MTX-resistant HT29 cells.</p> <p>Conclusion</p> <p>We provide functional evidences indicating that caveolin 1 and E-cadherin, deregulated in MTX resistant cells, may play a critical role in cell survival and may constitute potential targets for coadjuvant therapy.</p

Building capacity for dementia care in Latin America and the Caribbean

Latin America and the Caribbean (LAC) have limited facilities and professionals trained to diagnose, treat, and support people with dementia and other forms of cognitive impairment. The situation for people with dementia is poor, and worsening as the proportion of elderly in the general population is rapidly expanding. We reviewed existing initiatives and provided examples of actions taken to build capacity and improve the effectiveness of individuals, organizations, and national systems that provide treatment and support for people with dementia and their caregivers. Regional barriers to capacity building and the importance of public engagement are highlighted. Existing programs need to disseminate their objectives, accomplishments, limitations, and overall lessons learned in order to gain greater recognition of the need for capacity-building programs

El colesterol sigue alto. ¿Y ahora qué hacemos? Tratamiento de la hipercolesteremia no controlada a lo largo de un año

ObjetivoConocer la efectividad sobre el control lipídico del tratamiento hipolipemiante, basado en la práctica clínica habitual en atención primaria, en pacientes con hipercolesteremia manifiesta.DiseñoIntervención semiexperimental, antes-después.EmplazamientoCentro de salud urbano. Participantes: 187 pacientes dislipémicos conocidos, con colesterol total o colesterol LDL (cLDL) > 270 o 190 mg/dl, respectivamente.IntervenciónPráctica clínica habitual durante 12 meses en 9 consultas de atención primaria.Mediciones principalesSe registró el perfil lipídico y el tratamiento hipolipemiante al inicio del estudio y al cabo de 12 meses. El control lipídico (en función del cLDL) se evaluó como óptimo, aceptable y deficiente en función del riesgo cardiovascular según los criterios de la Sociedad Española de Arteriosclerosis (1994).ResultadosEn un 27% de casos no se registró ninguna visita relacionada con la hipercolesteremia por su médico. El número de pacientes tratados con hipolipemiantes creció de 50 a 98 (27 frente a 52%; p < 0,005), fundamentalmente a expensas del uso de estatinas. Tras 12 meses, se observaron descensos significativos en la concentración plasmática del cLDL (12%; IC del 95%, 9–15%) y del porcentaje de pacientes con control deficiente, que descendió del 91% inicial al 61% (p < 0,005), aunque sólo un 16% alcanzó un control óptimo.ConclusionesTras un año, con las condiciones de práctica clínica habitual, se observó un incremento en el uso de hipolipemiantes y una mejoría en el control lipídico, aunque algo más de la mitad de los pacientes (61%) con hipercolesteremia manifiesta permanecen con concentraciones tributarias de tratamiento.ObjectiveTo find the effectiveness of lipid-lowering treatment, based on normal clinical practice in primary care, on lipid control of patients with clear hypercholesterolaemia (HC).DesignSemi-experimental before-and-after intervention study.SettingUrban health centre. Participants: 187 patients known to have lipaemia, with total or LDL cCholesterol (cLDL) above 270 and 190 mg/dl, respectivelyInterventionNormal clinical practice for twelve months in nine primary care clinicsMain measurementsThe lipid profile and lipid-lowering treatment were recorded at the start of the study and after twelve months. Lipid control (as a function of cLDL) was evaluated as optimal, acceptable or deficient, as a function of the cardiovascular risk, following the criteria of the Spanish Arteriosclerosis Society (1994)ResultsIn 27% of cases, no visit relating to HC was recorded by the patient´s doctor. The number of patients treated with lipid-lowering drugs grew from 50 to 98 (27 vs 52%, p < 0,005), fundamentally at the expense of statin treatment. After twelve months, there were significant drops in the plasma concentration of cLDL (12%, 95%CI, 9 to 15%) and in the percentage of patients with deficient control, which fell from the initial 91% to 61% (p < 0.005), although only 16% reached optimal control.ConclusionsAfter a year, under conditions of normal clinical practice, there was an increase in the use of lipid-lowering drugs and improvement in lipid control, though a bit over half the patients (61%) with clear hypercholesterolaemia maintained concentrations requiring treatment

Compact Wideband Balanced Bandpass Filters With Very Broad Common-Mode and Differential-Mode Stopbands

[EN] Compact balanced bandpass filters based on a combination of multisection mirrored stepped-impedance resonators and interdigital capacitors are presented in this paper. The considered filter topology is useful to achieve wide bandwidths for the differential mode, with broad stop bands for that mode, as well as very efficient common-mode suppression. By conveniently adjusting the transmission zeros for both operation modes, the differential- and common-mode stopbands can be extended up to significantly high frequencies. Filter size and this differential- and common-mode stopband performance are the main relevant characteristics of the proposed balanced filters. The potential of the approach is illustrated by the design of a prototype order-5 balanced bandpass filter, with central frequency $f_{0} = 1.8$ GHz, 48% fractional bandwidth (corresponding to 55.4% ¿3-dB bandwidth), and 0.04-dB ripple level. The filter is automatically synthesized by means of an aggressive space-mapping software tool, specifically developed, and two (pre- and post-) optimization algorithms, necessary to determine the transmission-zero frequencies. The designed filter is as small as $0.48lambda _{g} times 0.51lambda _{g}$ , where $lambda _{g}$ is the guided wavelength at the central filter frequency, and the differential-mode stopband extends up to at least 6.5 GHz with more than 22-dB rejection. The common-mode suppression is better than 28 dB from dc up to at least 6.5 GHz.This work was supported in part by MINECO-Spain under Project TEC2013-40600-R, Project TEC2016-75650-R, and Project TEC2016-75934-C4-1-R, in part by the Generalitat de Catalunya under Project 2014SGR-157, in part by the Institucio Catalana de Recerca i Estudis Avancats (who awarded F. Martin), and in part by by FEDER funds.Sans, M.; Selga, J.; Vélez, P.; Bonache, J.; Rodríguez Pérez, AM.; Boria Esbert, VE.; Martin Antonlin, F. (2018). Compact Wideband Balanced Bandpass Filters With Very Broad Common-Mode and Differential-Mode Stopbands. IEEE Transactions on Microwave Theory and Techniques. 66(2):737-750. https://doi.org/10.1109/TMTT.2017.2785246S73775066

Generation of four induced pluripotent stem cell lines from a family harboring a single nucleotide variant in SCN5A

Patient-derived induced pluripotent stem cells (iPSC) are a valuable approach to model cardiovascular diseases. We nucleofected non-integrating episomal vectors in skin fibroblasts of three family members carrying a single nucleotide variant (SNV) in SCN5A, which encodes the cardiac-type sodium channel, and of a related healthy control. The SNV SCN5A_c.4573G > A had been previously identified in a Brugada Syndrome patient. The resulting iPS cell lines differentiate into cells of the 3 germ layers, display normal karyotypes and express pluripotency surface markers and genes. Thus, they are a reliable source to study the effect of the identified mutation in a physiologically relevant environment

Generation of an induced pluripotent stem cell line from a healthy Caucasian male

The effects of genetic mutations on protein function can be studied in a physiologically relevant environment using tissue-specific cells differentiated from patient-derived induced pluripotent stem cells (iPSC). However, it is crucial to use iPSC derived from healthy individuals as control. We generated an iPS cell line from skin fibroblasts of a healthy Caucasian male by nucleofection of non-integrating episomal vectors. This cell line has normal karyotype, expresses pluripotency surface markers and pluripotency genes, and successfully differentiates into cells of the 3 germ layers. Therefore, it can be used as control for any disease of interest that is modelled using iPSC

Automated synthesis of transmission lines loaded with complementary split ring resonators (CSRRs) and open complementary split ring resonators (OCSRRs) through aggressive space mapping (ASM)

This paper is focused on the application of space mapping optimization to the automated synthesis of transmission lines loaded with complementary split ring resonators (CSRRs) and open complementary split ring resonators (OCSRRs). These structures are of interest for the implementation of resonant-type metamaterial transmission lines and for the design of planar microwave circuits based on such complementary resonators. The paper presents a method to generate the layouts of CSRR- and OCSRR-loaded microstrip lines from the elements of their equivalent circuit models. Using the so-called aggressive space mapping, a specific implementation that uses quasi-Newton type iteration, we have developed synthesis algorithms that are able to provide the topology of these CSRR and OCSRR-loaded lines in few steps. The most relevant aspect, however, is that this synthesis process is completely automatic, i.e., it does not require any action from the designers, other than initiating the algorithm. Moreover, this technique can be translated to other electrically small planar elements described by lumped element equivalent circuit models.This work has been partially supported by MICIIN-Spain (Projects TEC2010-17512 METATRANSFER, TEC2010-21520-C04-01 AVANSAT, CONSOLIDER EMET CSD2008-00066, and Grant AP2008-04707), Generalitat de Catalunya (Project 2009SGR-421), and MITyC-Spain (Project TSI-020100-2010-169 METASINTESIS). Ferran Martin is in debt to ICREA for supporting his work through an ICREA Academia Award (calls 2008 and 2013).Selga, J.; Rodríguez Pérez, AM.; Orellana, M.; Boria Esbert, VE.; Martín, F. (2014). Automated synthesis of transmission lines loaded with complementary split ring resonators (CSRRs) and open complementary split ring resonators (OCSRRs) through aggressive space mapping (ASM). Applied Physics A. 117(2):557-565. https://doi.org/10.1007/s00339-014-8703-xS5575651172G.V. Eleftheriades, K.G. Balmain, Negative Refraction Metamaterials: Fundamental Principles and Applications (Wiley, New Jersey, 2005)C. Caloz, T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications (Wiley, New Jersey, 2006)R. Marqués, F. Martín, M. Sorolla, Metamaterials with Negative Parameters: Theory, Design and Microwave Applications (Wiley, New Jersey, 2008)F. Martín, Artificial Transmission Lines for RF and Microwave Applications. (Wiley, New Jersey) (to be published)M.A. Antoniades, G.V. Eleftheriades, A broadband series power divider using zero-degree metamaterial phase shifting lines. IEEE Microw. Wirel. Compon. Lett. 15, 808–810 (2005)H. Okabe, C. Caloz, T. Itoh, A compact enhanced bandwidth hybrid ring using an artificial lumped element left handed transmission line section. IEEE Trans. Microw. Theory Tech. 52, 798–804 (2004)G. Sisó, J. Bonache, M. Gil, F. Martín, Application of resonant-type metamaterial transmission lines to the design of enhanced bandwidth components with compact dimensions. Microw. Opt. Technol. Lett. 50, 127–134 (2008)I.H. Lin, M. De Vincentis, C. Caloz, T. Itoh, Arbitrary dual-band components using composite right/left handed transmission lines. IEEE Trans. Microw. Theory Tech. 52, 1142–1149 (2004)A.C. Papanastasiou, G.E. Georghiou, G.V. Eleftheriades, A quad-band Wilkinson power divider using generalized NRI transmission lines. IEEE Microw. Wirel. Compon. Lett. 18, 521–523 (2008)M. Durán-Sindreu, G. Sisó, J. Bonache, F. Martín, Planar multi-band microwave components based on the generalized composite right/left handed transmission line concept. IEEE Trans. Microw. Theory Tech. 58(12), 3882–3891 (2010)J. Bonache, I. Gil, J. García-García, F. Martín, Novel microstrip band pass filters based on complementary split ring resonators. IEEE Trans. Microw. Theory Tech. 54, 265–271 (2006)M. Gil, J. Bonache, J. García-García, J. Martel, F. Martín, Composite right/left handed (CRLH) metamaterial transmission lines based on complementary split rings resonators (CSRRs) and their applications to very wide band and compact filter design. IEEE Trans. Microw. Theory Tech. 55, 1296–1304 (2007)S. Lim, C. Caloz, T. Itoh, Metamaterial-based electronically-controlled transmission line structure as a novel leaky-wave antenna with tunable angle and beamwidth. IEEE Trans. Microw. Theory Tech. 52(12), 2678–2690 (2004)G. Zamora, S. Zuffanelli, F. Paredes, F. Javier Herraiz-Martínez, F. Martín, J. Bonache, Fundamental mode leaky-wave-antenna (LWA) using slot line and split-ring-resonator (SRR) based metamaterials. IEEE Antennas Wirel. Propag. Lett. 12, 1424–1427 (2013)A.K. Iyer, G.V. Eleftheriades, Negative refractive index metamaterials supporting 2-D waves. in IEEE-MTT Int’l Microwave Symposium, vol 2, Seattle, WA, pp. 412–415 (2002)A.A. Oliner, A periodic-structure negative-refractive-index medium without resonant elements. In URSI Digest, IEEE-AP-S USNC/URSI National Radio Science Meeting, San Antonio, TX, pp. 41 (2002)C. Caloz, T. Itoh, Application of the transmission line theory of left-handed (LH) materials to the realization of a microstrip LH transmission line. in Proceedings of IEEE-AP-S USNC/URSI National Radio Science Meeting, vol 2, San Antonio, TX, pp. 412–415 (2002)F. Martín, F. Falcone, J. Bonache, R. Marqués, M. Sorolla, Split ring resonator based left handed coplanar waveguide. Appl. Phys. Lett. 83, 4652–4654 (2003)F. Falcone, T. Lopetegi, M.A.G. Laso, J.D. Baena, J. Bonache, R. Marqués, F. Martín, M. Sorolla (2004) Babinet principle applied to the design of metasurfaces and metamaterials. Phys. Rev. Lett. 93, paper 197401M. Durán-Sindreu, A. Vélez, F. Aznar, G. Sisó, J. Bonache, F. Martín, Application of open split ring resonators and open complementary split ring resonators to the synthesis of artificial transmission lines and microwave passive components. IEEE Trans. Microw. Theory Tech. 57, 3395–3403 (2009)A. Vélez, F. Aznar, M. Durán-Sindreu, J. Bonache, F. Martín, Stop-band and band-pass filters in coplanar waveguide technology implemented by means of electrically small metamaterial-inspired open resonators. IET Microw. Antennas Propag. 4, 712–716 (2004)J.D. Baena, J. Bonache, F. Martín, R. Marqués, F. Falcone, T. Lopetegi, M.A.G. Laso, J. García, I. Gil, M. Flores-Portillo, M. Sorolla, Equivalent circuit models for split ring resonators and complementary split rings resonators coupled to planar transmission lines. IEEE Trans. Microw. Theory Tech. 53, 1451–1461 (2005)M. Gil, J. Bonache, J. Selga, J. García-García, F. Martín, Broadband resonant type metamaterial transmission lines. IEEE Microw. Wirel. Compon. Lett. 17, 97–99 (2007)M. Durán-Sindreu, P. Vélez, J. Bonache, F. Martín, Broadband microwave filters based on open split ring resonators (OSRRs) and open complementary split ring resonators (OCSRRs): improved models and design optimization. Radioengineering 20, 775–783 (2011)P. Vélez, J. Naqui, M. Durán-Sindreu, J. Bonache, F. Martín, Broadband microstrip bandpass filter based on open complementary split ring resonators. Int. J. Antennas Propag. 2012, 6 (2012)J.W. Bandler, R.M. Biernacki, S.H. Chen, P.A. Grobelny, R.H. Hemmers, Space mapping technique for electromagnetic optimization. IEEE Trans. Microw. Theory Tech. 42, 2536–2544 (1994)J.W. Bandler, R.M. Biernacki, S.H. Chen, R.H. Hemmers, K. Madsen, Electromagnetic optimization exploiting aggressive space mapping. IEEE Trans. Microw. Theory Tech. 43, 2874–2882 (1995)J.W. Bandler, Q.S. Cheng, S.A. Dakroury, A.S. Mohamed, M.H. Bakr, K. Madsen, J. Søndergaard, Space mapping: the state of the art. IEEE Trans. Microw. Theory Tech. 52, 337–361 (2004)C.G. Broyden, A class of methods for solving nonlinear simultaneous equations. Math. Comput. 19(92), 577–593 (1965)J. Selga, A. Rodríguez, V.E. Boria, F. Martín, Synthesis of split rings based artificial transmission lines through a new two-step, fast converging, and robust aggressive space mapping (ASM) algorithm. IEEE Trans. Microw. Theory Tech. 61(6), 2295–2308 (2013)A. Velez, F. Aznar, J. Bonache, M.C. Velázquez-Ahumada, J. Martel, F. Martín, Open complementary split ring resonators (OCSRRs) and their application to wideband CPW band pass filters. IEEE Microw. Wirel. Compon. Lett. 19, 197–199 (2009)D.M. Bates, D.G. Watts, Nonlinear Regression Analysis and Its Applications (Wiley, New York, 1998