898 research outputs found
Embedding Node Structural Role Identity into Hyperbolic Space
Recently, there has been an interest in embedding networks in hyperbolic
space, since hyperbolic space has been shown to work well in capturing
graph/network structure as it can naturally reflect some properties of complex
networks. However, the work on network embedding in hyperbolic space has been
focused on microscopic node embedding. In this work, we are the first to
present a framework to embed the structural roles of nodes into hyperbolic
space. Our framework extends struct2vec, a well-known structural role
preserving embedding method, by moving it to a hyperboloid model. We evaluated
our method on four real-world and one synthetic network. Our results show that
hyperbolic space is more effective than euclidean space in learning latent
representations for the structural role of nodes.Comment: In Proceedings of the 29th ACM International Conference on
Information and Knowledge Management (CIKM '20), October 19-23, 2020, Virtual
Event, Irelan
Polyfunctional T cell responses in children in early stages of chronic Trypanosoma cruzi infection contrast with monofunctional responses of long-term infected adults
Background: Adults with chronic Trypanosoma cruzi exhibit a poorly functional T cell compartment, characterized by monofunctional (IFN-γ-only secreting) parasite-specific T cells and increased levels of terminally differentiated T cells. It is possible that persistent infection and/or sustained exposure to parasites antigens may lead to a progressive loss of function of the immune T cells. Methodology/Principal Findings: To test this hypothesis, the quality and magnitude of T. cruzi-specific T cell responses were evaluated in T. cruzi-infected children and compared with long-term T. cruzi-infected adults with no evidence of heart failure. The phenotype of CD4+ T cells was also assessed in T. cruzi-infected children and uninfected controls. Simultaneous secretion of IFN-γ and IL-2 measured by ELISPOT assays in response to T. cruzi antigens was prevalent among T. cruzi-infected children. Flow cytometric analysis of co-expression profiles of CD4+ T cells with the ability to produce IFN-γ, TNF-α, or to express the co-stimulatory molecule CD154 in response to T. cruzi showed polyfunctional T cell responses in most T. cruzi-infected children. Monofunctional T cell responses and an absence of CD4+TNF-α+-secreting T cells were observed in T. cruzi-infected adults. A relatively high degree of activation and differentiation of CD4+ T cells was evident in T. cruzi-infected children. Conclusions/Significance: Our observations are compatible with our initial hypothesis that persistent T. cruzi infection promotes eventual exhaustion of immune system, which might contribute to disease progression in long-term infected subjects.Fil: Albareda, María Cecilia. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: de Rissio, Ana María. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Tomas, Gonzalo. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Serjan, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; ArgentinaFil: Alvarez, María Gabriela. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Viotti, Rodolfo Jorge. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Fichera, Laura Edith. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Esteva, Mónica Inés. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Potente, Daniel Fernando. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Armenti, Alejandro. Provincia de Buenos Aires. Ministerio de Salud. Hospital Interzonal de Agudos "Eva Perón"; ArgentinaFil: Tarleton, Rick L.. University of Georgia; Estados UnidosFil: Laucella, Susana Adriana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Type 1 plasminogen activator inhibitor (PAI-1) in clear cell renal cell carcinoma (CCRCC) and its impact on angiogenesis, progression and patient survival after radical nephrectomy
<p>Abstract</p> <p>Background</p> <p>To examine the expression of type 1 plasminogen inhibitor (PAI-1) in clear cell renal cell carcinoma (CCRCC), and its possible association with microvessel density (MVD), the expression of thrombospondin-1 (TSP-1), nuclear grade, tumour stage, continuously coded tumour size (CCTS) and to assess the value of PAI as a prognostic marker in 162 patients with CCRCC treated with radical nephrectomy.</p> <p>Methods</p> <p>A total of 172 consecutive patients with CCRCC treated with radical nephrectomy were enrolled in the study. The expression of PAI-1, TSP-1 and factor VIII were analysed on formalin-fixed, paraffin-embedded tissues without knowledge of the clinical outcome. Ten cases, where PAI-1 immunohistochemistry was not possible due to technical problems and lack of material, were excluded. Sixty-nine patients (43%) died of RCC, while 47 patients (29%) died of other diseases. Median follow-up was 13.8 years for the surviving 46 patients (28%).</p> <p>Results</p> <p>Nine percent of the tumours showed PAI-1 positivity. High expression of PAI-1 was significantly inversely correlated with TSP-1 (p = 0.046) and directly with advanced stage (p = 0.008), high NG (3+4) (p = 0.002), tumour size (p = 0.011), microvessel density (p = 0.049) and disease progression (p = 0.002). In univariate analysis PAI-1 was a significant prognosticator of cancer-specific survival (CSS) (p < 0.001). Multivariate analysis revealed that TNM stage (p < 0.001), PAI-1 (p = 0.020), TSP-1 (p < 0.001) and MVD (p = 0.007) were independent predictors of CSS.</p> <p>Conclusions</p> <p>PAI-1 was found to be an independently significant prognosticator of CSS and a promoter of tumour angiogenesis, aggressiveness and progression in CCRCC.</p
Death and Resurrection of the Human IRGM Gene
Immunity-related GTPases (IRG) play an important role in defense against intracellular pathogens. One member of this gene family in humans, IRGM, has been recently implicated as a risk factor for Crohn's disease. We analyzed the detailed structure of this gene family among primates and showed that most of the IRG gene cluster was deleted early in primate evolution, after the divergence of the anthropoids from prosimians ( about 50 million years ago). Comparative sequence analysis of New World and Old World monkey species shows that the single-copy IRGM gene became pseudogenized as a result of an Alu retrotransposition event in the anthropoid common ancestor that disrupted the open reading frame (ORF). We find that the ORF was reestablished as a part of a polymorphic stop codon in the common ancestor of humans and great apes. Expression analysis suggests that this change occurred in conjunction with the insertion of an endogenous retrovirus, which altered the transcription initiation, splicing, and expression profile of IRGM. These data argue that the gene became pseudogenized and was then resurrected through a series of complex structural events and suggest remarkable functional plasticity where alleles experience diverse evolutionary pressures over time. Such dynamism in structure and evolution may be critical for a gene family locked in an arms race with an ever-changing repertoire of intracellular parasites
Identification and Characterization of Two Functionally Unknown Genes Involved in Butanol Tolerance of Clostridium acetobutylicum
Solvents toxicity is a major limiting factor hampering the cost-effective biotechnological production of chemicals. In Clostridium acetobutylicum, a functionally unknown protein (encoded by SMB_G1518) with a hypothetical alcohol interacting domain was identified. Disruption of SMB_G1518 and/or its downstream gene SMB_G1519 resulted in increased butanol tolerance, while overexpression of SMB_G1518-1519 decreased butanol tolerance. In addition, SMB_G1518-1519 also influences the production of pyruvate:ferredoxin oxidoreductase (PFOR) and flagellar protein hag, the maintenance of cell motility. We conclude that the system of SMB_G1518-1519 protein plays a role in the butanol sensitivity/tolerance phenotype of C. acetobutylicum, and can be considered as potential targets for engineering alcohol tolerance
Hyperglycemia regulates thioredoxin-ROS activity through induction of thioredoxin-interacting protein (TXNIP) in metastatic breast cancer-derived cells MDA-MB-231
<p>Abstract</p> <p>Background</p> <p>We studied the RNA expression of the genes in response to glucose from 5 mM (condition of normoglycemia) to 20 mM (condition of hyperglycemia/diabetes) by microarray analysis in breast cancer derived cell line MDA-MB-231. We identified the thioredoxin-interacting protein (TXNIP), whose RNA level increased as a gene product particularly sensitive to the variation of the level of glucose in culture media. We investigated the kinesis of the TXNIP RNA and protein in response to glucose and the relationship between this protein and the related thioredoxin (TRX) in regulating the level of reactive oxygen species (ROS) in MDA-MB-231 cells.</p> <p>Methods</p> <p>MDA-MB-231 cells were grown either in 5 or 20 mM glucose chronically prior to plating. For glucose shift (5/20), cells were plated in 5 mM glucose and shifted to 20 mM at time 0. Cells were analyzed with Affymetrix Human U133A microarray chip and gene expression profile was obtained. Semi-quantitative RT-PCR and Western blot was used to validate the expression of TXNIP RNA and protein in response to glucose, respectively. ROS were detected by CM-H2DCFDA (5–6-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate) and measured for mean fluorescence intensity with flow cytometry. TRX activity was assayed by the insulin disulfide reducing assay.</p> <p>Results</p> <p>We found that the regulation of TXNIP gene expression by glucose in MDA-MB-231 cells occurs rapidly within 6 h of its increased level (20 mM glucose) and persists through the duration of the conditions of hyperglycemia. The increased level of TXNIP RNA is followed by increased level of protein that is associated with increasing levels of ROS and reduced TRX activity. The inhibition of the glucose transporter GLUT1 by phloretin notably reduces TXNIP RNA level and the inhibition of the p38 MAP kinase activity by SB203580 reverses the effects of TXNIP on ROS-TRX activity.</p> <p>Conclusion</p> <p>In this study we show that TXNIP is an oxidative stress responsive gene and its expression is exquisitely regulated by glucose level in highly metastatic MDA-MB-231 cells.</p
Regulation of membrane ruffling by polarized STIM1 and ORAI1in cortactin-rich domains
La movilidad celular y la migración requieren la reorganización del citoesqueleto cortical en el borde principal de las células y la entrada de Ca2 + extracelular es esencial para esta reorganización. Sin embargo, la naturaleza molecular de los reguladores de esta vía es desconocida. Este trabajo contribuye a comprender el papel de STIM1 y ORAI1 en la promoción de la ondulación de la membrana al mostrar que la fosfo-STIM1 se localiza en el borde principal de las células, y que tanto phospho-STIM1 como ORAI1 se localizan conjuntamente con la cortactina (CTTN), un regulador del citoesqueleto en las zonas de rizo de la membrana. Las líneas celulares STIM1-KO y ORAI1-KO se generaron mediante la edición del genoma CRISPR / Cas9 en células U2OS. En ambos casos, las células KO presentaron una reducción notable de la entrada de Ca2 + operada por el almacén (SOCE) que se rescató mediante la expresión de STIM1-mCherry y ORAI1-mCherry. Estos resultados demostraron que SOCE regula la deformación de la membrana en el borde anterior de las células. Por otra parte, ORAI1 endógeno y ORAI1-GFP sobreexpresado coinmuno precipitado con CTTN endógeno. Este último resultado, además del fenotipo de las células KO, la preservación de la co-localización de ORAI1-CTTN durante el fruncido, y la inhibición de la rizo de la membrana por parte del inhibidor del canal de Ca2 + SKF96365, apoya aún más un vínculo funcional entre el SOCE y el fruncido de la membrana.Cell motility and migration requires the reorganization of the cortical cytoskeleton at the leading edge of cells and extracellular Ca2+ entry is essential for this reorganization. However the molecular nature of the regulators of this pathway is unknown. This work contributes to understanding the role of STIM1 and ORAI1 in the promotion of membrane ruffling by showing that phospho-STIM1 localizes at the leading edge of cells, and that both phospho-STIM1 and ORAI1 co-localize with cortactin (CTTN), a regulator of the cytoskeleton at membrane ruffling areas. STIM1-KO and ORAI1-KO cell lines were generated by CRISPR/Cas9 genome editing in U2OS cells. In both cases, KO cells presented a notable reduction of store-operated Ca2+ entry (SOCE) that was rescued by expression of STIM1-mCherry and ORAI1-mCherry. These results demonstrated that SOCE regulates membrane ruffling at the leading edge of cells. Moreover, endogenous ORAI1 and overexpressed ORAI1-GFP co-immuno precipitated with endogenous CTTN. This latter result, in addition to the KO cells’ phenotype, the preservation of ORAI1-CTTN co-localization during ruffling, and the inhibition of membrane ruffling g by the Ca2+- channel inhibitor SKF96365, further supports a functional link between SOCE and membrane ruffling.• Ministerio de Economía y Competitividad y Fondo Social Europeo. Becas BFU2011-22798 y BFU2014-52401-P, para Francisco Javier Martín Romero
• Consejo de Investigación Médica. Beca MC_UU_12016 / 2, para Darío R. Alessi
• Ministerio de Economía y Competitividad. Beca BES-2012-052061, para Aida María López Guerrero
• Gobierno de Extremadura. Ayuda PD10081, para Patricia Tomás Martín
• Ministerio de Educación, Cultura y Deporte. Beca FPU13 / 03430, para Carlos Pascual Caro
• Consejo de Investigación Médica. Ayuda MR / K015869 / 1, para Graeme Ball
• EMBO. Beca ASTF-311-2014, para Eulalia Pozo Guisado
• Ministerio de Educación, Cultura Española y Deporte. Beca PRX14 / 00176, para Francisco Javier Martín RomeropeerReviewe
International entrepreneurship in SMEs: a study of influencing factors in the textile industry
The final publication is available at Springer via http://dx.doi.org/10.1007/s11365-012-0242-3International entrepreneurship is an incipient research area with a rapidly increasing body of knowledge and contributions. An important part of this literature has focused on the analysis of the contributing factors to IE development. From these studies, this work attempts to analyse and validate through an integrative model the effect on this construct in SME of some of the main factors proposed by the literature such as Skills and Competences, Attitude and Proactiveness, Creativity and Innovation, Networking, Employees and Activity. To proceed with this aim, we conducted an empirical research focused on 174 textile SME in Spain. The results obtained confirm a positive relationship between the studied factors and the IE development. In consequence, this work agrees with previous literature that point out the need to use multi-theoretical perspectives, combining multiple factors.Gil Pechuán, I.; Expósito Langa, M.; Tomas Miquel, JV. (2013). International entrepreneurship in SMEs: a study of influencing factors in the textile industry. International Entrepreneurship and Management Journal. 9(1):45-57. doi:10.1007/s11365-012-0242-3S455791Akgün, A., Keskin, H., & Byrne, J. (2012). Organizational emotional memory. Management Decision, 50(1), 95–114.Andersén, J. (2011). Strategic resources and firm performance. Management Decision, 49(1), 87–98.Anderson, A. R., Dodd, S. D., & Jack, S. L. (2012). Entrepreneurship as connecting: some implications for theorising and practice. Management Decision, 50(5), 958–971.Appelbaum, S. H., Roy, M., & Gilliland, T. (2011). Globalization of performance appraisals: theory and applications. Management Decision, 49(4), 570–585.Arribas, I., Hernández, P., Urbano, A., & Vila, J. E. (2012). Are social and entrepreneurial attitudes compatible? A behavioral and self-perceptional analysis. Management Decision, 50(10), 1739–1757.Audretsch, D. (2012). Entrepreneurship research. Management Decision, 50(5), 755–764.Autio, E., Sapienza, H. J., & Almeida, J. G. (2000). Effects of age at entry, knowledge intensity, and imitability on international growth. Academy of Management Journal, 43, 909–924.Bannon, L. (1998). Mattel plans to double sales abroad. Wall Street Journal, February 11, (A3 and A8).Battistella, C., Biotto, G., & De Toni, A. (2012). From design driven innovation to meaning strategy. Management Decision, 50(4), 718–743.Bell, J., McNaughton, J., Young, R., & Crick, D. (2003). Towards an integrative model of small firm internationalization. Journal of International Entrepreneurship, 1, 339–362.Bonzo, P., Valadares de Oliveira, P., & McCormarck. (2012). Planning, capabilities, and performance: an integrated value approach. Management Decision, 50(6), 1001–1021.Bossak, J., & Nagashima, S. (1997). Corporate strategies for a borderless world: sharpening your competitive edge. Tokyo: Asian Productivity Organization.Cambra-Fierro, J., Florin, J., Perez, L., & Whitelock, J. (2011). Inter-firm market orientation as antecedent of knowledge transfer, innovation and value creation in networks. Management Decision, 49(3), 444–467.Cantarello, S., Nosella, A., Petroni, G., & Venturini, K. (2011). External technology sourcing: evidence from design-driven innovation. Management Decision, 49(6), 962–983.Chang, Y. Y., Hughes, M., & Hotho, S. (2011). Internal and external antecedents of SMEs’ innovation ambidexterity outcomes. Management Decision, 49(10), 1658–1676.Chaston, I., & Scott, G. J. (2012). Entrepreneurship and open innovation in an emerging economy. Management Decision, 50(7), 1161–1177.Coviello, N. E., & Jones, M. V. (2004). Methodological issues in international entrepreneurship research. Journal of Business Venturing, 19, 485–508.Coviello, N. E., & McAuley, A. (1999). Internationalization and the smaller firm: a review of contemporary empirical research. Management International Review, 39, 223–256.Covin, J., & Slevin, D. (1989). Strategic management of small firms in hostile and benign environments. Strategic Management Journal, 10(1), 75–87.Covin, J., & Slevin, D. (1991). A conceptual model of entrepreneurship as firm behavior. Entrepreneurship Theory and Practice, 16, 7–25.Davis, D., Morris, M., & Allen, J. (1991). Perceived environmental turbulence and its effect on selected entrepreneurship, marketing, and organizational characteristics in industrial firms. Journal of the Academy of Marketing Science, 19(1), 43–51.Dean, C. C., Thibodeaux, M. S., Beyerlein, M., Ebrahimi, B., & Molina, D. (1993). Corporate entrepreneurship and competitive aggressiveness. A comparison of U.S. firms operating in eastern Europe and the Commonwealth of Independent States with U.S. firms in other high-risk environments. Advances in International Comparative Management, 8, 31–54.Dess, G. G., & Robinson, R. B. (1984). Measuring organizational performance in the absence of objective measures: the case of privately held firms and conglomerate business units. Strategic Management Journal, 5, 265–273.Dess, G. G., Lumpkin, G. T., & Covin, J. G. (1997). Entrepreneurial strategy making and firm performance: tests of contingency and configurational models. Strategic Management Journal, 18, 677–695.Díaz-Casero, J. C., Díaz-Aunión, A., Sánchez-Escobedo, M. C., Coduras-Martinez, A., & Hernández-Mogollón, R. (2012). Economic freedom and entrepreneurial activity. Management Decision, 50(9), 1686–1711.Dimitratos, P., & Plakoyiannaki, E. (2003). Theoretical foundations of an international entrepreneurial culture. Journal of International Entrepreneurship, 1, 187–215.Dubini, P., & Aldrich, H. (1991). Personal and extended networks are central to the entrepreneurial process. Journal of Business Venturing, 6, 305–313.Felício, J. A., Rodrigues, R., & Caldeirinha, V. R. (2012). The effect of intrapreneurship on corporate performance. Management Decision, 50(10), 1717–1738.Goktan, A. B., & Miles, G. (2011). Innovation speed and radicalness: are they inversely related? Management Decision, 49(4), 533–547.Gómez-Haro, S., Aragón-Correa, J. A., & Cordón-Pozo, E. (2011). Differentiating the effects of the institutional environment on corporate entrepreneurship. Management Decision, 49(10), 1677–1693.Hitt, M. A., Ireland, R. D., Camp, S. M., & Sexton, L. D. (2001). Strategic entrepreneurship: entrepreneurial strategies for wealth creation [Special Issue]. Strategic Management Journal, 22(6), 479–492.Hotho, S., & Champion, K. (2011). Small businesses in the new creative industries: innovation as a people management challenge. Management Decision, 49(1), 29–54.Hu, Y.-S. (1995). The international transferability of competitive advantage. California Management Review, 37(4), 73–88.Huarng, K. H., & Yu, T. H. K. (2011). Entrepreneurship, process innovation and value creation by a non-profit SME. Management Decision, 49(2), 284–296.Jones, M. V. (1999). The internationalization of small UK high technology based firms. Journal of International Marketing, 7, 15–41.Jones, M. V., & Coviello, N. E. (2005). Internationalization: conceptualising and entrepreneurial process of behaviour in time. Journal of International Business Studies, 36(3):284–303.Khandwalla, P. (1977). The design of organizations. New York: Harcourt Brace Jovanovich.Knight, G. A., & Cavusgil, S. T. (2004). Innovation, organization capabilities, and the born-global firm. Journal of International Business Studies, 35, 124–141.Kropp, F., Lindsay, N. J., & Shoham, A. (2006). Entrepreneurial, market, and learning orientations and international entrepreneurial business venture performance in South African firms. International Marketing Review, 23(5), 504–523.Liebeskind, J. P. (1996). Knowledge, strategy, and the theory of the firm. Strategic Management Journal, 17, 93–107.Lumpkin, G. T., & Dess, G. G. (1996). Clarifying the entrepreneurial construct and linking it to performance. Academy of Management Review, 21, 135–172.McDougall, P. P., & Oviatt, B. M. (2000). International entrepreneurship: the intersection of two research paths. Academy of Management Journal, 43, 902–908.McDougall, P. P., Shane, S., & Oviatt, B. M. (1994). Explaining the formation of international new ventures: the limits of theories from international business research. Journal of Business Venturing, 9, 469–487.McGrath, R. G., MacMillan, I. C., & Venkataraman, S. (1995). Global dimensions of new competencies. In S. Birley & I. C. MacMillan (Eds.), International entrepreneurship. New York: Routledge.McNaughton, R. B. (2001). The export mode decision-making process in small knowledge- intensive firms. Market Intelligence and Planning, 19, 12–20.McNaughton, R. B. (2003). The number of export markets that a firm serves: process models versus the born-global phenomenon. Journal of International Entrepreneurship, 1, 297–311.Miles, R. E., & Snow, C. C. (1978). Organizational strategy, structure and process. New York: McGraw-Hill.Miller, D. (1983). The correlates of entrepreneurship in three types of firms. Management Science, 29(7), 770–791.Miller, D., & Friesen, P. (1984). Organizations: a quantum view. Englewood Cliffs: Prentice-Hall.Morrow, J. F. (1988). International entrepreneurship: a new growth opportunity. New Management, 3, 59–61.Murphy, G. B., Trailer, J. W., & Hill, R. C. (1996). Measuring performance in entrepreneurship research. Journal of Business Research, 36, 15–23.Naman, J. L., & Slevin, D. P. (1993). Entrepreneurship and the concept of fit: a model and empirical tests. Strategic Management Journal, 14, 137–153.Naranjo-Valencia, J. C., Jiménez-Jiménez, D., & Sanz-Valle, R. (2011). Innovation or imitation? The role of organizational culture. Management Decision, 49(1), 55–72.Oviatt, B. M., & McDougall, P. P. (1994). Toward a theory of international new ventures. Journal of International Business Studies, 25(1), 45–64.Oviatt, B. M., & McDougall, P. P. (1999). A framework for understanding accelerated international entrepreneurship. In R. Wright (Ed.), Research in global strategic management (pp. 23–40). Stamford: JAI Press.Oviatt, B. M., & McDougall, P. P. (2005). Defining international entrepreneurship and modeling the speed of internalization. Entrepreneurship Theory & Practice, 29(5), 537–554.Peiris, I.K., Akoorie, M.E.M., & Sinha, P.N. (2012). International entrepreneurship: A critical analysis of studies in the past two decades and future directions for research. Journal of International Entrepreneurship. Article in press.Pinchot, G., III. (1985). Intrapreneuring: why you don’t have to leave the corporation to become entrepreneur. New York: Harper and Row Publishers.Porter, M. (1990). The competitive advantage of nations. London: Collier-Macmillan.Renko, M., Shrader, R. C., & Simon, M. (2012). Perception of entrepreneurial opportunity: a general framework. Management Decision, 50(7), 1233–1251.Sandulli, F. D., Fernandez-Menendez, J., Rodriguez-Duarte, A., & Lopez-Sanchez, J. I. (2012). Testing the Schumpeterian hypotheses on an open innovation framework. Management Decision, 50(7), 1222–1232.Santos, F. J., Romero, I., & Fernández-Serrano, J. (2012). SMEs and entrepreneurial quality from a macroeconomic perspective. Management Decision, 50(8), 1382–1395.Shama, A. (1995). Entry strategies of U.S. firms to the former Soviet Bloc and Eastern Europe. California Management Review, 37(3), 90–109.Simon, H. (1996). Hidden champions: lessons from 500 of the world’s best unknown companies. Boston: Harvard Business School Press.Singh, S., Darwish, T. K., Costa, A. C., & Anderson, N. (2012). Measuring HRM and organisational performance: concepts, issues, and framework. Management Decision, 50(4), 651–667.Smart, T. (1996). GE’s Welch: ‘Fighting like hell to be No. 1’. Business Week, July 8, 48.Snow, C., & Hrebiniak, L. (1980). Strategy, distinctive competence, and organizational performance. Administrative Science Quarterly, 25, 317–336.Stevenson, H. H., & Jarillo, J. C. (1990). A paradigm of entrepreneurship: entrepreneurial management. Strategic Management Journal, 11, 17–27.Styles, C., & Seymour, R. G. (2006). Opportunities for marketing researchers in international entrepreneurship. International Marketing Review, 23(2), 126–145.Turner, R., Ledwith, A., & Kelly, J. (2012). Project management in small to medium-sized enterprises: tailoring the practices to the size of company. Management Decision, 50(5), 942–957.Venkatraman, N., & Ramanujam, V. (1986). Measurement of business performance in strategy research: a comparison of approaches. Academy of Management Review, 11, 801–814.Vlasic, B. (1998). The little car that could carry Chrysler overseas. Business Week, 19, 39.Welbourne, T. M., Neck, H., & Meyer, G. D. (2012). The entrepreneurial growth ceiling: using people and innovation to mitigate risk and break through the growth ceiling in initial public offerings. Management Decision, 50(5), 778–796.Williamson, P. J. (1997). Asia’s new competitive game. Harvard Business Review, 75(5), 55–67.Yeoh, P. L. (2004). International learning: antecedents and performance implications among newly internationalizing companies in an exporting context. International Marketing Review, 21(4/5), 511–535.Zahra, S. A. (1991). Predictors and financial outcomes of corporate entrepreneurship. An exploratory study. Journal of Business Venturing, 6(4), 259–285.Zahra, S. A. (1993a). Environment, corporate entrepreneurship and financial performance. A taxonomic approach. Journal of Business Venturing, 8(4), 319–340.Zahra, S. A. (1993b). A conceptual model of entrepreneurship as firm behavior: a critique and extensión. Entrepreneurship Theory and Practice, 17(4), 5–21.Zahra, S. A., & George, G. (2002). International entrepreneurship: the current status of the field and future agenda. In M. A. Hitt, R. D. Ireland, S. M. Camp, & D. L. Sexton (Eds.), Strategic entrepreneurship: creating a new mindset. Oxford: Blackwell Publishers.Zahra, S. A., Jennings, D. F., & Kuratko, D. F. (1999). The antecedents and consequences of firm-level entrepreneurship: the state of the field. Entrepreneurship Theory and Practice, 24(2), 45–63.Zhou, L. (2007). The effects of entrepreneurial proclivity and foreign market knowledge on early internationalization. Journal of World Business, 42(3), 281–293
Group II Intron-Anchored Gene Deletion in Clostridium
Clostridium plays an important role in commercial and medical use, for which targeted gene deletion is difficult. We proposed an intron-anchored gene deletion approach for Clostridium, which combines the advantage of the group II intron “ClosTron” system and homologous recombination. In this approach, an intron carrying a fragment homologous to upstream or downstream of the target site was first inserted into the genome by retrotransposition, followed by homologous recombination, resulting in gene deletion. A functional unknown operon CAC1493–1494 located in the chromosome, and an operon ctfAB located in the megaplasmid of C. acetobutylicum DSM1731 were successfully deleted by using this approach, without leaving antibiotic marker in the genome. We therefore propose this approach can be used for targeted gene deletion in Clostridium. This approach might also be applicable for gene deletion in other bacterial species if group II intron retrotransposition system is established
Architecture of androgen receptor pathways amplifying glucagon-like peptide-1 insulinotropic action in male pancreatic β cells
Male mice lacking the androgen receptor (AR) in pancreatic β cells exhibit blunted glucose-stimulated insulin secretion (GSIS), leading to hyperglycemia. Testosterone activates an extranuclear AR in β cells to amplify glucagon-like peptide-1 (GLP-1) insulinotropic action. Here, we examined the architecture of AR targets that regulate GLP-1 insulinotropic action in male β cells. Testosterone cooperates with GLP-1 to enhance cAMP production at the plasma membrane and endosomes via: (1) increased mitochondrial production of CO2, activating the HCO3--sensitive soluble adenylate cyclase; and (2) increased Gαs recruitment to GLP-1 receptor and AR complexes, activating transmembrane adenylate cyclase. Additionally, testosterone enhances GSIS in human islets via a focal adhesion kinase/SRC/phosphatidylinositol 3-kinase/mammalian target of rapamycin complex 2 actin remodeling cascade. We describe the testosterone-stimulated AR interactome, transcriptome, proteome, and metabolome that contribute to these effects. This study identifies AR genomic and non-genomic actions that enhance GLP-1-stimulated insulin exocytosis in male β cells
- …