The Experts below are selected from a list of 1599 Experts worldwide ranked by ideXlab platform
Marlon R. Schneider - One of the best experts on this subject based on the ideXlab platform.
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Structure and function of Epigen, the last EGFR ligand.
Seminars in cell & developmental biology, 2013Co-Authors: Marlon R. Schneider, Yosef YardenAbstract:Epigen is the latest addition to the mammalian family of EGFR ligands. Epigen was initially identified as a novel expressed sequence tag with homology to the EGF family by high throughput sequencing of a mouse keratinocyte complementary DNA library, and received its name for its ability to act as an epithelial mitogen. In vitro studies attributed to Epigen several unique features, such as persistent and potent biological actions involving low affinity receptor binding, as well as sub-maximal receptor activation and inactivation. Similarly to the other EGFR ligands, the expression of Epigen is up-regulated by hormones and in certain cancer types. While the biological functions of Epigen remain to be uncovered, it appears to play a role in epidermal structures, such as the mammary gland and the sebaceous gland. The latter organ, in particular, was greatly enlarged in transgenic mice overexpressing Epigen. Interestingly, mice lacking Epigen develop and grow normally, probably due to functional compensation by other EGFR ligands. Future studies are likely to reveal the biological roles of the unique receptor binding properties of Epigen, as well as its potential harnessing during disease.
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Increased activation of the epidermal growth factor receptor in transgenic mice overexpressing Epigen causes peripheral neuropathy.
Biochimica et biophysica acta, 2013Co-Authors: Maik Dahlhoff, Eckhard Wolf, Daniela Emrich, Marlon R. SchneiderAbstract:In the mammalian nervous system, axons are commonly surrounded by myelin, a lipid-rich sheath that is essential for precise and rapid conduction of nerve impulses. In the peripheral nervous system (PNS), myelin sheaths are formed by Schwann cells which wrap around individual axons. While the tyrosine kinase receptors ERBB2 and ERBB3 are established mediators of peripheral myelination, less is known about the functions of the related epidermal growth factor receptor (EGFR) in the regulation of PNS myelination. Here, we report a peripheral neurodegenerative disease caused by increased EGFR activation. Specifically, we characterize a symmetric and distally pronounced, late-onset muscular atrophy in transgenic mice overexpressing the EGFR ligand Epigen. Histological examination revealed a demyelinating neuropathy and axon degeneration, and molecular analysis of signaling pathways showed reduced protein kinase B (PKB, AKT) activation in the nerves of Epigen-tg mice, indicating that the muscular phenotype is secondary to PNS demyelination and axon degeneration. Crossing of Epigen-tg mice into an EGFR-deficient background revealed the pathology to be completely EGFR-dependent. This mouse line provides a new model for studying molecular events associated with early stages of peripheral neuropathies, an essential prerequisite for the development of successful therapeutic interventions.
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Genetic deletion of the EGFR ligand Epigen does not affect mouse embryonic development and tissue homeostasis.
Experimental cell research, 2012Co-Authors: Maik Dahlhoff, Matthias Schäfer, Eckhard Wolf, Marlon R. SchneiderAbstract:The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor with manifold functions during development, tissue homeostasis and disease. EGFR activation, the formation of homodimers or heterodimers (with the related ERBB2-4 receptors) and downstream signaling is initiated by the binding of a family of structurally related growth factors, the EGFR ligands. Genetic deletion experiments clarified the biological function of all family members except for the last characterized ligand, Epigen. We employed gene targeting in mouse embryonic stem cells to generate mice lacking Epigen expression. Loss of Epigen did not affect mouse development, fertility, or organ physiology. Quantitative RT-PCR analysis revealed increased expression of betacellulin and EGF in a few organs of Epigen-deficient mice, suggesting a functional compensation by these ligands. In conclusion, we completed the genetic analysis of EGFR ligands and show that Epigen has non-essential functions or functions that can be compensated by other EGFR ligands during growth and tissue homeostasis.
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Epigen Transgenic Mice Develop Enlarged Sebaceous Glands
The Journal of investigative dermatology, 2009Co-Authors: Maik Dahlhoff, Eckhard Wolf, Anna-katharina Müller, Sabine Werner, Marlon R. SchneiderAbstract:Abbreviations: BrdU, bromodeoxyuridine; CMV, cytomegalovirus; EGFR, epidermal growth factor receptor; EPGN, Epigen; Gapdh, glyceraldehyde-3-phosphate dehydrogenase; TGF-α, transforming growth factor-alpha
Akilah Hugine - One of the best experts on this subject based on the ideXlab platform.
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Intelliject’s novel epinephrine autoinjector: sharps injury prevention validation and comparable analysis with EpiPen and
2015Co-Authors: Stephanie Guerlain, Lu Wang, Akilah HugineAbstract:Background—Currently marketed epinephrine autoinjectors (EAs) are prone to misuse that may lead to injury or a missed dose. A novel EA (NEA) (Intelliject Inc) was created to reduce such injuries by including features such as a unidirectional perceived injection end and a retractable needle. Objectives—To validate the sharps injury prevention features of the NEA and to obtain feedback on, and preference for, features of the NEA compared with Twinject and EpiPen. Methods—Twenty-eight health care professionals experienced with using the EpiPen or Twinject each injected 18 NEAs into an orange and provided confirmation of needle injection and retraction. Half of the injections were conducted using wet hands to replicate diaphoretic hands or wet environmental conditions. Participants provided feedback via a post-test questionnaire and gave ordinal preference rankings for the NEA, EpiPen, and Twinject based on shape, size, ease of use, ease of training, and overall preference. Participants also described known cases in which the Twinject or EpiPen was not correctly administered. Results—For all 505 tested NEAs, the needle injected and retracted as intended. For overall preference, 100 % of the experienced health care practitioners ranked the NEA first. Half of the participants recalled incidents in which the EpiPen or Twinject did not work as intended or caused an injury. Conclusions—The sharps injury prevention feature was verified for the NEA, and health care professionals experienced in the use of EpiPen and Twinject for allergic emergencies perceived the NEA to be a safer and preferred alternative
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intelliject s novel epinephrine autoinjector sharps injury prevention validation and comparable analysis with epipen and twinject
Annals of Allergy Asthma & Immunology, 2010Co-Authors: Stephanie Guerlain, Lu Wang, Akilah HugineAbstract:Background Currently marketed epinephrine autoinjectors (EAs) are prone to misuse that may lead to injury or a missed dose. A novel EA (NEA) (Intelliject Inc) was created to reduce such injuries by including features such as a unidirectional perceived injection end and a retractable needle. Objectives To validate the sharps injury prevention features of the NEA and to obtain feedback on, and preference for, features of the NEA compared with Twinject and EpiPen. Methods Twenty-eight health care professionals experienced with using the EpiPen or Twinject each injected 18 NEAs into an orange and provided confirmation of needle injection and retraction. Half of the injections were conducted using wet hands to replicate diaphoretic hands or wet environmental conditions. Participants provided feedback via a post-test questionnaire and gave ordinal preference rankings for the NEA, EpiPen, and Twinject based on shape, size, ease of use, ease of training, and overall preference. Participants also described known cases in which the Twinject or EpiPen was not correctly administered. Results For all 505 tested NEAs, the needle injected and retracted as intended. For overall preference, 100% of the experienced health care practitioners ranked the NEA first. Half of the participants recalled incidents in which the EpiPen or Twinject did not work as intended or caused an injury. Conclusions The sharps injury prevention feature was verified for the NEA, and health care professionals experienced in the use of EpiPen and Twinject for allergic emergencies perceived the NEA to be a safer and preferred alternative.
Maik Dahlhoff - One of the best experts on this subject based on the ideXlab platform.
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Increased activation of the epidermal growth factor receptor in transgenic mice overexpressing Epigen causes peripheral neuropathy.
Biochimica et biophysica acta, 2013Co-Authors: Maik Dahlhoff, Eckhard Wolf, Daniela Emrich, Marlon R. SchneiderAbstract:In the mammalian nervous system, axons are commonly surrounded by myelin, a lipid-rich sheath that is essential for precise and rapid conduction of nerve impulses. In the peripheral nervous system (PNS), myelin sheaths are formed by Schwann cells which wrap around individual axons. While the tyrosine kinase receptors ERBB2 and ERBB3 are established mediators of peripheral myelination, less is known about the functions of the related epidermal growth factor receptor (EGFR) in the regulation of PNS myelination. Here, we report a peripheral neurodegenerative disease caused by increased EGFR activation. Specifically, we characterize a symmetric and distally pronounced, late-onset muscular atrophy in transgenic mice overexpressing the EGFR ligand Epigen. Histological examination revealed a demyelinating neuropathy and axon degeneration, and molecular analysis of signaling pathways showed reduced protein kinase B (PKB, AKT) activation in the nerves of Epigen-tg mice, indicating that the muscular phenotype is secondary to PNS demyelination and axon degeneration. Crossing of Epigen-tg mice into an EGFR-deficient background revealed the pathology to be completely EGFR-dependent. This mouse line provides a new model for studying molecular events associated with early stages of peripheral neuropathies, an essential prerequisite for the development of successful therapeutic interventions.
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Genetic deletion of the EGFR ligand Epigen does not affect mouse embryonic development and tissue homeostasis.
Experimental cell research, 2012Co-Authors: Maik Dahlhoff, Matthias Schäfer, Eckhard Wolf, Marlon R. SchneiderAbstract:The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor with manifold functions during development, tissue homeostasis and disease. EGFR activation, the formation of homodimers or heterodimers (with the related ERBB2-4 receptors) and downstream signaling is initiated by the binding of a family of structurally related growth factors, the EGFR ligands. Genetic deletion experiments clarified the biological function of all family members except for the last characterized ligand, Epigen. We employed gene targeting in mouse embryonic stem cells to generate mice lacking Epigen expression. Loss of Epigen did not affect mouse development, fertility, or organ physiology. Quantitative RT-PCR analysis revealed increased expression of betacellulin and EGF in a few organs of Epigen-deficient mice, suggesting a functional compensation by these ligands. In conclusion, we completed the genetic analysis of EGFR ligands and show that Epigen has non-essential functions or functions that can be compensated by other EGFR ligands during growth and tissue homeostasis.
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Epigen Transgenic Mice Develop Enlarged Sebaceous Glands
The Journal of investigative dermatology, 2009Co-Authors: Maik Dahlhoff, Eckhard Wolf, Anna-katharina Müller, Sabine Werner, Marlon R. SchneiderAbstract:Abbreviations: BrdU, bromodeoxyuridine; CMV, cytomegalovirus; EGFR, epidermal growth factor receptor; EPGN, Epigen; Gapdh, glyceraldehyde-3-phosphate dehydrogenase; TGF-α, transforming growth factor-alpha
Stephanie Guerlain - One of the best experts on this subject based on the ideXlab platform.
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Intelliject’s novel epinephrine autoinjector: sharps injury prevention validation and comparable analysis with EpiPen and
2015Co-Authors: Stephanie Guerlain, Lu Wang, Akilah HugineAbstract:Background—Currently marketed epinephrine autoinjectors (EAs) are prone to misuse that may lead to injury or a missed dose. A novel EA (NEA) (Intelliject Inc) was created to reduce such injuries by including features such as a unidirectional perceived injection end and a retractable needle. Objectives—To validate the sharps injury prevention features of the NEA and to obtain feedback on, and preference for, features of the NEA compared with Twinject and EpiPen. Methods—Twenty-eight health care professionals experienced with using the EpiPen or Twinject each injected 18 NEAs into an orange and provided confirmation of needle injection and retraction. Half of the injections were conducted using wet hands to replicate diaphoretic hands or wet environmental conditions. Participants provided feedback via a post-test questionnaire and gave ordinal preference rankings for the NEA, EpiPen, and Twinject based on shape, size, ease of use, ease of training, and overall preference. Participants also described known cases in which the Twinject or EpiPen was not correctly administered. Results—For all 505 tested NEAs, the needle injected and retracted as intended. For overall preference, 100 % of the experienced health care practitioners ranked the NEA first. Half of the participants recalled incidents in which the EpiPen or Twinject did not work as intended or caused an injury. Conclusions—The sharps injury prevention feature was verified for the NEA, and health care professionals experienced in the use of EpiPen and Twinject for allergic emergencies perceived the NEA to be a safer and preferred alternative
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intelliject s novel epinephrine autoinjector sharps injury prevention validation and comparable analysis with epipen and twinject
Annals of Allergy Asthma & Immunology, 2010Co-Authors: Stephanie Guerlain, Lu Wang, Akilah HugineAbstract:Background Currently marketed epinephrine autoinjectors (EAs) are prone to misuse that may lead to injury or a missed dose. A novel EA (NEA) (Intelliject Inc) was created to reduce such injuries by including features such as a unidirectional perceived injection end and a retractable needle. Objectives To validate the sharps injury prevention features of the NEA and to obtain feedback on, and preference for, features of the NEA compared with Twinject and EpiPen. Methods Twenty-eight health care professionals experienced with using the EpiPen or Twinject each injected 18 NEAs into an orange and provided confirmation of needle injection and retraction. Half of the injections were conducted using wet hands to replicate diaphoretic hands or wet environmental conditions. Participants provided feedback via a post-test questionnaire and gave ordinal preference rankings for the NEA, EpiPen, and Twinject based on shape, size, ease of use, ease of training, and overall preference. Participants also described known cases in which the Twinject or EpiPen was not correctly administered. Results For all 505 tested NEAs, the needle injected and retracted as intended. For overall preference, 100% of the experienced health care practitioners ranked the NEA first. Half of the participants recalled incidents in which the EpiPen or Twinject did not work as intended or caused an injury. Conclusions The sharps injury prevention feature was verified for the NEA, and health care professionals experienced in the use of EpiPen and Twinject for allergic emergencies perceived the NEA to be a safer and preferred alternative.
Irwan - One of the best experts on this subject based on the ideXlab platform.
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Invers Matriks Laplace yang Digeneralisasi dan Pembuktian Teorema-teorema yang Berkaitan
2013Co-Authors: Irwan Susanto, IrwanAbstract:The Laplacian Mtarix is a representation of the a connected graph. The Laplacian Matris is reaql and simetric matrix. The Laplacian matrix also singular matrix because the sum of each row and each is zero coloumns. Eigen value and eigen vector of Laplacian matrix is . From that equation we can see that zero is one of eigen value of the Laplacian Matrix. So, invers of the Laplacian matrix will be generalized because we cant defined inverses the Laplacian matrix is zero. And then we will established the some properties of the generalized of the Laplacian matrix. Theoem and Lemma learning from this mini thesis of the generalized invers of the Laplacian matrix will be proved in this work.
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Invers Matriks Laplace yang Digeneralisasi dan Pembuktian Teorema-teorema yang Berkaitan
2013Co-Authors: Irwan Susanto, IrwanAbstract:The Laplacian Mtarix is a representation of the a connected graph. The Laplacian Matris is reaql and simetric matrix. The Laplacian matrix also singular matrix because the sum of each row and each is zero coloumns. Eigen value and eigen vector of Laplacian matrix is . From that equation we can see that zero is one of eigen value of the Laplacian Matrix. So, invers of the Laplacian matrix will be generalized because we cant defined inverses the Laplacian matrix is zero. And then we will established the some properties of the generalized of the Laplacian matrix. Theoem and Lemma learning from this mini thesis of the generalized invers of the Laplacian matrix will be proved in this work.