124 results on '"Speck N"'
Search Results
2. Tyrosyl phosphorylation toggles a Runx1 switch
- Author
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Neel, B. G., primary and Speck, N. A., additional
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- 2012
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3. Development of Allosteric Inhibitors of the Interaction of AML1 and CBFβ for the Treatment of Leukemia.
- Author
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Douvas, Michael G., primary, Roudaiya, L., additional, Grembecka, J., additional, Speck, N., additional, and Bushweller, J.H., additional
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- 2007
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4. Overexpression of core-binding factor alpha (CBF alpha) reverses cellular transformation by the CBF beta-smooth muscle myosin heavy chain chimeric oncoprotein
- Author
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Hajra, A, primary, Liu, P P, additional, Speck, N A, additional, and Collins, F S, additional
- Published
- 1996
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5. Disruption of the Cbfa2 gene causes necrosis and hemorrhaging in the central nervous system and blocks definitive hematopoiesis.
- Author
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Wang, Q, primary, Stacy, T, additional, Binder, M, additional, Marin-Padilla, M, additional, Sharpe, A H, additional, and Speck, N A, additional
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- 1996
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6. Overexpression of core-binding factor alpha (CBF alpha) reverses cellular transformation by the CBF beta-smooth muscle myosin heavy chain chimeric oncoprotein
- Author
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Hajra, A, primary, Liu, P P, additional, Speck, N A, additional, and Collins, F S, additional
- Published
- 1995
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7. Transactivation of the Moloney murine leukemia virus and T-cell receptor beta-chain enhancers by cbf and ets requires intact binding sites for both proteins
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Sun, W, primary, Graves, B J, additional, and Speck, N A, additional
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- 1995
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8. Transcriptional activity of core binding factor-alpha (AML1) and beta subunits on murine leukemia virus enhancer cores
- Author
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Zaiman, A L, primary, Lewis, A F, additional, Crute, B E, additional, Speck, N A, additional, and Lenz, J, additional
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- 1995
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9. The leukemic core binding factor beta-smooth muscle myosin heavy chain (CBF beta-SMMHC) chimeric protein requires both CBF beta and myosin heavy chain domains for transformation of NIH 3T3 cells.
- Author
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Hajra, A, primary, Liu, P P, additional, Wang, Q, additional, Kelley, C A, additional, Stacy, T, additional, Adelstein, R S, additional, Speck, N A, additional, and Collins, F S, additional
- Published
- 1995
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10. Cooperative binding of Ets-1 and core binding factor to DNA.
- Author
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Wotton, D, primary, Ghysdael, J, additional, Wang, S, additional, Speck, N A, additional, and Owen, M J, additional
- Published
- 1994
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11. Cloning and characterization of subunits of the T-cell receptor and murine leukemia virus enhancer core-binding factor
- Author
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Wang, S, primary, Wang, Q, additional, Crute, B E, additional, Melnikova, I N, additional, Keller, S R, additional, and Speck, N A, additional
- Published
- 1993
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12. Characterization of a protein that binds multiple sequences in mammalian type C retrovirus enhancers
- Author
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Sun, W, primary, O'Connell, M, additional, and Speck, N A, additional
- Published
- 1993
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13. Sequence specificity of the core-binding factor
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Melnikova, I N, primary, Crute, B E, additional, Wang, S, additional, and Speck, N A, additional
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- 1993
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14. Two factors that bind to highly conserved sequences in mammalian type C retroviral enhancers
- Author
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Manley, N R, primary, O'Connell, M, additional, Sun, W, additional, Speck, N A, additional, and Hopkins, N, additional
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- 1993
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15. Indistinguishable nuclear factor binding to functional core sites of the T-cell receptor delta and murine leukemia virus enhancers
- Author
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Redondo, J M, primary, Pfohl, J L, additional, Hernandez-Munain, C, additional, Wang, S, additional, Speck, N A, additional, and Krangel, M S, additional
- Published
- 1992
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16. A phorbol ester response element within the human T-cell receptor beta-chain enhancer.
- Author
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Prosser, H M, primary, Wotton, D, additional, Gegonne, A, additional, Ghysdael, J, additional, Wang, S, additional, Speck, N A, additional, and Owen, M J, additional
- Published
- 1992
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17. Purification of core-binding factor, a protein that binds the conserved core site in murine leukemia virus enhancers
- Author
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Wang, S W, primary and Speck, N A, additional
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- 1992
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18. cis-acting elements in the U3 region of a simian immunodeficiency virus
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Renjifo, B, primary, Speck, N A, additional, Winandy, S, additional, Hopkins, N, additional, and Li, Y, additional
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- 1990
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19. Point mutations in the Moloney murine leukemia virus enhancer identify a lymphoid-specific viral core motif and 1,3-phorbol myristate acetate-inducible element
- Author
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Speck, N A, primary, Renjifo, B, additional, and Hopkins, N, additional
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- 1990
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20. Alignment of U3 region sequences of mammalian type C viruses: identification of highly conserved motifs and implications for enhancer design
- Author
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Golemis, E A, primary, Speck, N A, additional, and Hopkins, N, additional
- Published
- 1990
- Full Text
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21. Mutation of the core or adjacent LVb elements of the Moloney murine leukemia virus enhancer alters disease specificity.
- Author
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Speck, N A, primary, Renjifo, B, additional, Golemis, E, additional, Fredrickson, T N, additional, Hartley, J W, additional, and Hopkins, N, additional
- Published
- 1990
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22. Biophysical characterization of interactions between the core binding factor a and b subunits and DNA
- Author
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Tang, Y. Y., Crute, B. E., III, J. J. Kelley, Huang, X., Yan, J., Shi, J., Hartman, K. L., Laue, T. M., Speck, N. A., and Bushweller, J. H.
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- 2000
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23. Cbfa2 is required for the formation of intra-aortic hematopoietic clusters.
- Author
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North, T, Gu, T L, Stacy, T, Wang, Q, Howard, L, Binder, M, Marín-Padilla, M, and Speck, N A
- Abstract
Cbfa2 (AML1) encodes the DNA-binding subunit of a transcription factor in the small family of core-binding factors (CBFs). Cbfa2 is required for the differentiation of all definitive hematopoietic cells, but not for primitive erythropoiesis. Here we show that Cbfa2 is expressed in definitive hematopoietic progenitor cells, and in endothelial cells in sites from which these hematopoietic cells are thought to emerge. Endothelial cells expressing Cbfa2 are in the yolk sac, the vitelline and umbilical arteries, and in the ventral aspect of the dorsal aorta in the aorta/genital ridge/mesonephros (AGM) region. Endothelial cells lining the dorsal aspect of the aorta, and elsewhere in the embryo, do not express Cbfa2. Cbfa2 appears to be required for maintenance of Cbfa2 expression in the endothelium, and for the formation of intra-aortic hematopoietic clusters from the endothelium.
- Published
- 1999
24. Overexpression, purification, and biophysical characterization of the heterodimerization domain of the core-binding factor beta subunit.
- Author
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Huang, X, Crute, B E, Sun, C, Tang, Y Y, Kelley, J J, Lewis, A F, Hartman, K L, Laue, T M, Speck, N A, and Bushweller, J H
- Abstract
Core-binding factors (CBF) are heteromeric transcription factors essential for several developmental processes, including hematopoiesis. CBFs contain a DNA-binding CBF alpha subunit and a non-DNA binding CBF beta subunit that increases the affinity of CBF alpha for DNA. We have developed a procedure for overexpressing and purifying full-length CBF beta as well as a truncated form containing the N-terminal 141 amino acids using a novel glutaredoxin fusion expression system. Substantial quantities of the CBF beta proteins can be produced in this manner allowing for their biophysical characterization. We show that the full-length and truncated forms of CBF beta bind to a CBF alpha DNA complex with very similar affinities. Sedimentation equilibrium measurements show these proteins to be monomeric. Circular dichroism spectroscopy demonstrates that CBF beta is a mixed alpha/beta protein and NMR spectroscopy shows that the truncated and full-length proteins are structurally similar and suitable for structure determination by NMR spectroscopy.
- Published
- 1998
25. Biochemical and biophysical properties of the core-binding factor alpha2 (AML1) DNA-binding domain.
- Author
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Crute, B E, Lewis, A F, Wu, Z, Bushweller, J H, and Speck, N A
- Abstract
The Runt domain is the DNA-binding domain defining a small family of transcription factors that are involved in important developmental processes. Developmental pathways controlled by Runt domain proteins include sex determination, neurogenesis, segmentation, and eye development in Drosophila and hematopoiesis in mammals. In addition to binding DNA, the Runt domain also mediates heterodimerization with another subunit called the core-binding factor beta (CBFbeta) subunit. In this study we overexpress the Runt domain from the mouse CBFalpha2 (AML1) protein in Escherichia coli, and purify it from the insoluble fraction. We determine the equilibrium constants for Runt domain binding to two different DNA sequences by surface plasmon resonance technology. Circular dichroism spectroscopy demonstrates that the Runt domain is a folded beta-domain with essentially no alpha-helical content. The single tryptophan residue in the CBFalpha2 Runt domain at amino acid 79 is shown by tryptophan fluorescence spectroscopy to reside in a polar environment. Finally, we demonstrate that ATP can be UV cross-linked to the Runt domain and that ATP binding is sensitive to an amino acid substitution in the putative Kinase-1a motif (P-loop).
- Published
- 1996
26. Six distinct nuclear factors interact with the 75-base-pair repeat of the Moloney murine leukemia virus enhancer
- Author
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Speck, N A and Baltimore, D
- Abstract
Binding sites for six distinct nuclear factors on the 75-base-pair repeat of the Moloney murine leukemia virus enhancer have been identified by an electrophoretic mobility shift assay combined with methylation interference. Three of these factors, found in WEHI 231 nuclear extracts, which we have named LVa, LVb, and LVc (for leukemia virus factors a, b, and c) have not been previously identified. Nuclear factors that bind to the conserved simian virus 40 corelike motif, the NF-1 motif, and the glucocorticoid response element were also detected. Testing of multiple cell lines showed that most factors appeared ubiquitous, except that the NF-1 binding factor was found neither in nuclear extracts from MEL cells nor in the embryonal carcinoma cell lines PCC4 and F9, and core-binding factor was relatively depleted from MEL and F9 nuclear extracts.
- Published
- 1987
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27. The collaborative phenotype of secondary B cells is determined by T lymphocytes during in vivo immunization.
- Author
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Speck, N A and Pierce, S K
- Abstract
Previous studies have demonstrated that the B cells in immune and nonimmune mice manifest different major histocompatibility complex (MHC) collaborative phenotypes with antigen-specific T cells. Immune, or secondary B cells require syngeneic-like MHC recognition by collaborating T cells, and in its absence fail to be stimulated. Primary B cells manifest a much less stringent requisite for MHC recognition by T cells, and under conditions in which secondary B cells fail to be stimulated, primary B cells are stimulated to secrete IgM antibody. Experiments were conducted to determine whether the acquisition of the secondary B cells' MHC collaborative phenotype was dependent on the presence of T cells during in vivo immunization. B cell populations from T dependently and T independently immunized conventional BALB/c and athymic BALB/c nu/nu mice were compared in their ability to collaborate with allogeneic T cells. Although antigen alone promotes the differentiation of several secondary B cell characteristics, including an increase in the frequency of antigen-specific B cells and a preference for IgG1 antibody synthesis in vitro, the acquisition of the secondary B cells' MHC collaborative phenotype was dependent on the presence of T cells during in vivo immunization. B cell populations from T dependently and T independently immunized conventional BALB/c and athymic BALB/c nu/nu mice were compared in their ability to collaborate with allogeneic T cells. Although antigen alone promotes the differentiation of several secondary B cell characteristics, including an increase in the frequency of antigen-specific B cells and a preference of IgG1 antibody synthesis in vitro, the acquisition of the secondary B cells' MHC collaborative phenotype was found to be dependent on the presence of T cells during in vivo immunization. Thus, the restriction imposed on T cell-B-cell-collaborative interactions in secondary humoral immune responses appears to be the result of T dependent antigen-driven events.
- Published
- 1982
- Full Text
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28. Balb/c T cells have the potential to recognize the TEPC 15 prototype antibody and its somatic variants.
- Author
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Pierce, S K, Speck, N A, Gleason, K, Gearhart, P J, and Köhler, H
- Abstract
Immunization of BALB/c mice with phosphorylcholine-Limulus polyphemus hemocyanin (PC-Hy) induces a population of T cells that recognize the predominant PC-binding antibody, TEPC15 (T15). The splenic fragment culture system was used to examine the specificity of these T cells for a series of PC-binding myeloma and hybridoma antibodies representing the prototype variable region of the heavy chain (VH)T 15 sequence as well as somatic variants of the T15 germ line-encoded sequence. Included in this group of PC-binding proteins were both T15-positive and T15-negative antibodies, as defined by anti-idiotypic antibody. T cell help was identified by the ability to promote TNP-specific B cell responses to trinitrophenylated PC-binding proteins. It was found that T cells generated by immunization with PC-Hy recognize both antibodies with the T15 prototype sequence and the putative somatic variants of this sequence. A population of these T cells appear to recognize common determinants shared by these proteins because immunization with T15 itself also induces the recognition of the somatic variants. This suggests that idiotopes encoded in the T15 germ line gene expressed by the T15 prototype idiotype and the somatic variants can function as targets for T cell recognition and are thus regulatory idiotopes.
- Published
- 1981
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29. Relação entre angiogênese e estádio no carcinoma do endométrio
- Author
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Speck Neila Maria de Góis, Focchi José, Alves Antonio Correa, Osório Cintia Aparecida Bueno, and Baracat Edmund Chada
- Subjects
Angiogênese ,Endométrio/carcinoma ,Prognóstico ,Gynecology and obstetrics ,RG1-991 - Abstract
OBJETIVO: avaliar se o número de vasos neoformados é fator importante para o prognóstico do adenocarcinoma endometrial, comparando-o com o grau de diferenciação histológica e o estadiamento do tumor. MÉTODOS: foram estudadas 56 amostras de tecido endometrial, sendo 11 com o diagnóstico histológico de endométrio atrófico, 10 endométrios proliferativos (ambos caracterizados como grupos controle), 10 amostras de adenocarcinomas GI, 13 adenocarcinomas GII e 12 adenocarcinomas GIII, caracterizados como grupos de estudo. Dois cortes histológicos foram obtidos de cada caso: um foi corado pela hematoxilina-eosina e o outro, para estudo imuno-histoquímico, foi tratado com anti-CD34, com a finalidade de corar vasos. A contagem vascular foi realizada na interface do crescimento tumoral com o estroma adjacente, em dez campos de 100 vezes de aumento, mediante estudo morfométrico pelo sistema computadorizado Kontron S300. No grupo controle, foi selecionada a interface entre glândulas endometriais e estroma adjacente. RESULTADOS: a média de vasos contados em 10 campos foi de 11,6 para o endométrio atrófico; 13,2 para o proliferativo; 15,3 para o adenocarcinoma GI; 19 para o adenocarcinoma GII e 22,7 para o adenocarcinoma GIII. A média de quantificação vascular para os tumores das pacientes incluídas no estadiamento clínico I foi 18,6, semelhante estatisticamente àquelas dos estadiamentos II, III e IV (20,9) computados em conjunto. CONCLUSÃO: concluímos que o adenocarcinoma pouco diferenciado apresenta maior número de vasos por campo que o endométrio normal e que o carcinoma bem diferenciado. A quantificação vascular não foi influenciada pelo estadiamento como fator isolado.
- Published
- 2003
30. A novel RUNX2 missense mutation predicted to disrupt DNA binding causes cleidocranial dysplasia in a large Chinese family with hyperplastic nails
- Author
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Wang Xiaoqin, Jiang Yusheng, Yang Xuemei, Du Jicheng, Xu Xueqin, Xu Qiyu, Tang Shaohua, Speck Nancy, and Huang Taosheng
- Subjects
Internal medicine ,RC31-1245 ,Genetics ,QH426-470 - Abstract
Abstract Background Cleidocranial dysplasia (CCD) is a dominantly inherited disease characterized by hypoplastic or absent clavicles, large fontanels, dental dysplasia, and delayed skeletal development. The purpose of this study is to investigate the genetic basis of Chinese family with CCD. Methods Here, a large Chinese family with CCD and hyperplastic nails was recruited. The clinical features displayed a significant intrafamilial variation. We sequenced the coding region of the RUNX2 gene for the mutation and phenotype analysis. Results The family carries a c.T407C (p.L136P) mutation in the DNA- and CBFβ-binding Runt domain of RUNX2. Based on the crystal structure, we predict this novel missense mutation is likely to disrupt DNA binding by RUNX2, and at least locally affect the Runt domain structure. Conclusion A novel missense mutation was identified in a large Chinese family with CCD with hyperplastic nails. This report further extends the mutation spectrum and clinical features of CCD. The identification of this mutation will facilitate prenatal diagnosis and preimplantation genetic diagnosis.
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- 2007
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31. Perforator versus Non-Perforator Flap-Based Vulvoperineal Reconstruction-A Systematic Review and Meta-Analysis.
- Author
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Wendelspiess S, Kouba L, Stoffel J, Speck N, Appenzeller-Herzog C, Gahl B, Montavon C, Heinzelmann-Schwarz V, Lariu A, Schaefer DJ, Ismail T, and Kappos EA
- Abstract
Background: Patients with advanced vulvoperineal cancer require a multidisciplinary treatment approach to ensure oncological safety, timely recovery, and the highest possible quality of life (QoL). Reconstructions in this region often lead to complications, affecting approximately 30% of patients. Flap design has evolved towards perforator-based approaches to reduce functional deficits and (donor site) complications, since they allow for the preservation of relevant anatomical structures. Next to their greater surgical challenge in elevation, their superiority over non-perforator-based approaches is still debated., Methods: To compare outcomes between perforator and non-perforator flaps in female vulvoperineal reconstruction, we conducted a systematic review of English-language studies published after 1980, including randomized controlled trials, cohort studies, and case series. Data on demographics and surgical outcomes were extracted and classified using the Clavien-Dindo classification. We used a random-effects meta-analysis to derive a pooled estimate of complication frequency (%) in patients who received at least one perforator flap and in patients who received non-perforator flaps., Results: Among 2576 screened studies, 49 met our inclusion criteria, encompassing 1840 patients. The overall short-term surgical complication rate was comparable in patients receiving a perforator ( n = 276) or a non-perforator flap ( n = 1564) reconstruction ( p * > 0.05). There was a tendency towards fewer complications when using perforator flaps. The assessment of patients' QoL was scarce., Conclusions: Vulvoperineal reconstruction using perforator flaps shows promising results compared with non-perforator flaps. There is a need for the assessment of its long-term outcomes and for a systematic evaluation of patient QoL to further demonstrate its benefit for affected patients.
- Published
- 2024
- Full Text
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32. Understanding the impact of spinal cord injury on the microbiota of healthy skin and pressure injuries.
- Author
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Wettstein R, Valido E, Buergin J, Haumer A, Speck N, Capossela S, Stoyanov J, and Bertolo A
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- Humans, RNA, Ribosomal, 16S genetics, Skin microbiology, Bacteria genetics, Pressure Ulcer, Spinal Cord Injuries microbiology, Microbiota genetics
- Abstract
Pressure injuries (PI) are a common issue among individuals with spinal cord injury (SCI), especially in the sitting areas of the body. Considering the risk of infections occurring to PI during the wound healing process, the skin microbiome is likely to be a source of bacteria. We investigated the relationship between skin and PI microbiomes, and assessed any correlation with clinically relevant outcomes related to PI. Samples were isolated from SCI patients undergoing reconstructive surgery of PI, severity grades III and IV. DNA samples from skin and PI were analysed using 16S rRNA gene sequencing. Our results showed disparities in microbiome composition between skin and PI. The skin had lower diversity, while PI showed increased bacterial homogeneity as the severity grade progressed. The skin bacterial composition varied based on its location, influenced by Cutibacterium. Compositional differences were identified between PI grades III and IV, with clusters of bacteria colonizing PI, characterized by Pseudomonas, Proteus and Peptoniphilus. The skin and PI microbiomes were not affected by the level of the SCI. Our study highlights the differences in the microbiome of skin and PI in SCI patients. These findings could be used to target specific bacteria for PI treatment in clinical practice., (© 2023. The Author(s).)
- Published
- 2023
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33. RUNX-1 haploinsufficiency causes a marked deficiency of megakaryocyte-biased hematopoietic progenitor cells.
- Author
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Estevez B, Borst S, Jarocha D, Sudunagunta V, Gonzalez M, Garifallou J, Hakonarson H, Gao P, Tan K, Liu P, Bagga S, Holdreith N, Tong W, Speck N, French DL, Gadue P, and Poncz M
- Subjects
- Adult, Base Sequence, Core Binding Factor Alpha 2 Subunit genetics, Flow Cytometry, Haploinsufficiency, Humans, Immunophenotyping, Induced Pluripotent Stem Cells cytology, MAP Kinase Signaling System, Neoplastic Syndromes, Hereditary genetics, Platelet Glycoprotein GPIb-IX Complex analysis, RNA, Small Interfering genetics, Recombinant Proteins metabolism, Signal Transduction, Single-Cell Analysis, Thrombopoiesis, Transforming Growth Factor beta1 physiology, Core Binding Factor Alpha 2 Subunit deficiency, Hematopoietic Stem Cells pathology, Megakaryocytes pathology, Neoplastic Syndromes, Hereditary pathology
- Abstract
Patients with familial platelet disorder with a predisposition to myeloid malignancy (FPDMM) harbor germline monoallelic mutations in a key hematopoietic transcription factor, RUNX-1. Previous studies of FPDMM have focused on megakaryocyte (Mk) differentiation and platelet production and signaling. However, the effects of RUNX-1 haploinsufficiency on hematopoietic progenitor cells (HPCs) and subsequent megakaryopoiesis remains incomplete. We studied induced pluripotent stem cell (iPSC)-derived HPCs (iHPCs) and Mks (iMks) from both patient-derived lines and a wild-type (WT) line modified to be RUNX-1 haploinsufficient (RUNX-1+/-), each compared with their isogenic WT control. All RUNX-1+/- lines showed decreased iMk yield and depletion of an Mk-biased iHPC subpopulation. To investigate global and local gene expression changes underlying this iHPC shift, single-cell RNA sequencing was performed on sorted FPDMM and control iHPCs. We defined several cell subpopulations in the Mk-biased iHPCs. Analyses of gene sets upregulated in FPDMM iHPCs indicated enrichment for response to stress, regulation of signal transduction, and immune signaling-related gene sets. Immunoblot analyses in FPDMM iMks were consistent with these findings, but also identified augmented baseline c-Jun N-terminal kinase (JNK) phosphorylation, known to be activated by transforming growth factor-β1 (TGF-β1) and cellular stressors. These findings were confirmed in adult human CD34+-derived stem and progenitor cells (HSPCs) transduced with lentiviral RUNX1 short hairpin RNA to mimic RUNX-1+/-. In both iHPCs and CD34+-derived HSPCs, targeted inhibitors of JNK and TGF-β1 pathways corrected the megakaryopoietic defect. We propose that such intervention may correct the thrombocytopenia in patients with FPDMM.
- Published
- 2021
- Full Text
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34. HPV genotyping and p16 expression in Xingu Indigenous Park, Brazil.
- Author
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Freitas VG, Focchi GR, Pereira ER, Levi JE, Speck NM, and Ribalta JC
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- Adult, Aged, Biomarkers, Tumor genetics, Brazil, Colposcopy, Cyclin-Dependent Kinase Inhibitor p16 genetics, Female, Gene Expression Regulation, Genotype, Human papillomavirus 16 genetics, Human papillomavirus 16 isolation & purification, Human papillomavirus 16 pathogenicity, Human papillomavirus 31 genetics, Human papillomavirus 31 isolation & purification, Human papillomavirus 31 pathogenicity, Humans, Middle Aged, Papillomavirus Infections pathology, Papillomavirus Infections virology, Uterine Cervical Dysplasia pathology, Uterine Cervical Dysplasia virology, Biomarkers, Tumor biosynthesis, Cyclin-Dependent Kinase Inhibitor p16 biosynthesis, Papillomavirus Infections genetics, Uterine Cervical Dysplasia genetics
- Abstract
The association between high-risk human papillomavirus (HPV) genotypes and p16 expression in indigenous women from the Xingu Indigenous Park, Brazil, was unknown. This study evaluated p16 expression in women with a histological diagnosis of cervical intraepithelial neoplasia (CIN) 3 or higher and correlated this expression with HPV genotypes to determine possible discrepancies in the expression of this marker. We evaluated 37 previously collected samples with different HPV genotypes and high-grade lesions diagnosed based on cytology, histology, and colposcopy. Immunohistochemical analysis was performed using paraffin-embedded tissue sections and the CINtec® Histology Kit. p16 protein expression was investigated by immunostaining with an anti-p16 antibody. HPV genotyping was performed by reverse hybridization. The age of the study population ranged from 22-75 years (43.81 ± 15.89 years) and parity ranged from 1-11 (5.92 ± 2.58). Thirteen different HPV genotypes were found using the INNO-LiPA kit. Single and multiple infections by HPV were found with prevalence of single infections (P = 0.029). Comparison between HPV genotype and simple or multiple infections was highly significant; it was observed more HPV 52 followed by HPV 16 in single infections (P < 0.001). p16 expression was predominantly diffuse, which was observed in 91.7% of lesions, whereas 8.3% were focal (P < 0.001). HPV 52, HPV 16 and 31 were the most prevalent HPV types in high-grade CIN in these indigenous women. Diffuse p16 expression in high-grade CIN was not influenced by the viral genotype; however, more studies are necessary to further our understanding of this restricted group.
- Published
- 2016
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35. Expression of human papillomavirus E6 and E7 oncoprotein mRNA in women with low-grade squamous intraepithelial lesions or less.
- Author
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Casagrande DC, Ribalta JC, Leite KD, Schimidt M, and Speck NM
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- Adolescent, Adult, Aged, Female, Humans, Middle Aged, Oncogene Proteins, Viral metabolism, Papillomavirus E7 Proteins metabolism, RNA, Messenger metabolism, Repressor Proteins metabolism, Squamous Intraepithelial Lesions of the Cervix pathology, Squamous Intraepithelial Lesions of the Cervix virology, Oncogene Proteins, Viral genetics, Papillomavirus E7 Proteins genetics, RNA, Messenger genetics, Repressor Proteins genetics, Squamous Intraepithelial Lesions of the Cervix genetics
- Abstract
We verified the prevalence of human papillomavirus (HPV) E6/E7 protein mRNA expression in patients with low-grade squamous intraepithelial lesions (LSILs) and negative cervicovaginal cytology. To investigate the relationship between mRNA expression and viral infection type, we assessed genotyping in single infections. Samples from 825 women were submitted to the E6/E7 survey. We noticed a larger percentage of E6/E7 mRNA expression in the atypical squamous cells of undetermined significance (ASC-US) and LSIL cytologies. Negative results of mRNA expression were in accordance with negative cytologies. In positive cases, the infection by a single HPV type was most common, with type 16 being most prevalent. The expression of mRNA was most prevalent in ASC-US and LSIL cytologies, compared with the negative cytology. The infection by a HPV type was more frequent in cases of positive expression, with HPV type 16 being found most frequently. Patients with LSIL cytologies had a higher percentage of multiple infections.
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- 2016
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36. Immunoexpression of HPV 16/18 E6 and E7 oncoproteins in high-grade cervical squamous intraepithelial lesions in HIV-positive women.
- Author
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Rodrigues LC, Speck NM, Focchi GR, Schimidt MA, Marques RM, and Ribalta JC
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- Adolescent, Adult, Aged, Coinfection, Female, HIV growth & development, HIV Infections genetics, HIV Infections immunology, HIV Infections virology, Human papillomavirus 16 genetics, Human papillomavirus 16 growth & development, Human papillomavirus 18 genetics, Human papillomavirus 18 growth & development, Humans, Immunohistochemistry, Middle Aged, Neoplasm Grading, Oncogene Proteins, Viral biosynthesis, Papillomavirus E7 Proteins biosynthesis, Papillomavirus Infections genetics, Papillomavirus Infections immunology, Papillomavirus Infections virology, Repressor Proteins biosynthesis, Squamous Intraepithelial Lesions of the Cervix genetics, Squamous Intraepithelial Lesions of the Cervix immunology, Squamous Intraepithelial Lesions of the Cervix virology, Tissue Array Analysis, Uterine Cervical Neoplasms genetics, Uterine Cervical Neoplasms immunology, Uterine Cervical Neoplasms virology, Gene Expression Regulation, Viral, HIV Infections pathology, Oncogene Proteins, Viral genetics, Papillomavirus E7 Proteins genetics, Papillomavirus Infections pathology, Repressor Proteins genetics, Squamous Intraepithelial Lesions of the Cervix pathology, Uterine Cervical Neoplasms pathology
- Abstract
The aim of this study was to assess the immunoexpression of human papillomavirus genotypes 16 and 18 (E6 and E7) oncoproteins in cervical high-grade squamous intraepithelial lesions (HSIL) of human immunodeficiency virus (HIV)-positive women. These results were also compared to the persistence and/or recurrence of lesions after loop electrosurgical excision procedure. Cervical samples from 158 patients were divided into three groups according to the presence or absence of HSIL in women who were or were not HIV-positive. By using the tissue microarray technique, immunohistochemistry was performed to analyze the expression of HPV 16/18 E6 and E7 oncoproteins. Cervical samples from 95 HIV-positive women and 63 HIV-negative women were studied. A statistically significant difference was found in the immunoexpression of E6 and E7 oncoproteins in samples from HIV-positive women with HSIL and that of women with non-neoplastic tissue (P < 0.001). There was also a statistically significant correlation between the immunoexpression of E6 (P = 0.012) and E7 (P < 0.001) oncoproteins in lesion persistence among HIV-positive women. Within the limitations of this study, the immunoexpression of HPV 16/18 E6 and E7 oncoproteins may have prognostic value regarding lesion persistence in HIV-positive women.
- Published
- 2016
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37. HPV infection-associated anogenital cyto-colpo-histological findings and molecular typing in HIV-positive women.
- Author
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Tso FK, Rodrigues CL, Levi JE, Mattosinho de Castro Ferraz MG, Speck NM, and Ribalta JC
- Subjects
- Adolescent, Adult, Anal Canal pathology, Anal Canal virology, Coinfection complications, Coinfection pathology, Female, Genotype, HIV genetics, HIV isolation & purification, HIV pathogenicity, HIV Infections complications, HIV Infections genetics, HIV Infections pathology, Humans, Middle Aged, Oncogene Proteins, Viral biosynthesis, Papillomaviridae genetics, Papillomaviridae isolation & purification, Papillomaviridae pathogenicity, Papillomavirus Infections complications, Papillomavirus Infections genetics, Papillomavirus Infections pathology, RNA, Messenger biosynthesis, Repressor Proteins biosynthesis, Reproductive Tract Infections complications, Reproductive Tract Infections genetics, Reproductive Tract Infections pathology, Vaginal Smears, Coinfection virology, HIV Infections virology, Papillomavirus Infections virology, Reproductive Tract Infections virology
- Abstract
HIV and human papillomavirus (HPV) coinfection is increasing, especially in the anal canal (AC) and cervico-vaginal regions. We identified anal epithelium abnormalities related to high-risk HPV (HR-HPV) lesions in the lower genital tracts (LGTs) of HIV-positive women, described the HPV genotypes identified, and assessed the expression of E6/E7 oncogenes in coinfected patients. Ninety-eight women were enrolled in groups combining HIV status and presence or absence of HPV in the LGT. Anal and cervical smears were collected for cytology and HR-HPV assays using Cobas(®) and/or PapilloCheck(®). Samples with highly oncogenic HPV genotypes were confirmed by NucliSENS EasyQ(®). Forty-two HIV-positive (25-52; mean age 39.5) and 56 HIV-negative (18-58; mean age 35.7) patients were included. E2 and C1 groups presented AC alterations (P = 0.002); altered images for high-resolution anoscopy were higher in E1 and C2 (P < 0.001). Of the 29 women with alterations, 41.38% were HIV-negative and 58.62% were HIV-positive (P < 0.001). HIV-positive patients accounted for 29% of the anal high-grade squamous intraepithelial lesions (P = 0.015). The Cobas(®) positive result frequency was higher in three AC groups than in the other groups. There was variation in the number of HPV types in the cervico-vaginal samples among the study groups (P < 0.001). Anal cytology and anoscopy showed more altered findings in HIV-positive patients with HPV in the LGT. HR-HPV anal infections by various genotypes are common and are associated with cervical infections in HIV-positive patients. E6/E7 expression is apparently more common in the AC of HIV-positive women.
- Published
- 2015
- Full Text
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38. A Medical Student-Driven "Vaccine Blitz" at a School-Based Health Center as an Effective Way to Improve Adolescent Vaccination Rates.
- Author
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Eldred SV, Hamid HS, Snider JC, Weinberg SH, Speck N, Reed BD, and Riley M
- Subjects
- Adolescent, Female, Humans, Male, Michigan, Immunization Programs statistics & numerical data, Professional Role, School Health Services, Students, Medical
- Abstract
Background and Objectives: Adolescent vaccine rates are below goal in the United States. We sought to assess a medical student driven "vaccine blitz" at a middle school with a school-based health center (SBHC) as a means to increase vaccination., Methods: Written and/or verbal consent was obtained for specific vaccines needed. Vaccines were given at the SBHC by a team of medical students, public health students, and SBHC staff. Students who received vaccines at the SBHC or primary care physician's (PCP's) office in the 3 weeks after consent was attempted were included as participating in the intervention., Results: Of 184 potential participants, 183 lacked at least one vaccine. On the day of the vaccine blitz, 48 students were given 94 vaccines. During the entire intervention time, an additional 14 students received 38 vaccines at the SBHC, and 23 students received 34 vaccines from their PCP. In sum, 85 students received 166 vaccines from this intervention. Immunization rates increased above the state average for all recommended vaccines; rates of HPV, hepatitis A, and influenza vaccination were most affected., Conclusions: Medical student-driven vaccine blitzes within an SBHC are a feasible, replicable, and effective way to increase adolescent vaccination rates. In addition, the blitz provided preclinical medical students' exposure to underserved populations, adolescent health as part of the breadth of family medicine, SBHCs, and community medicine and allowed for multidisciplinary work between medical students, public health students, physicians, and nurse practitioners.
- Published
- 2015
39. An interesting finding in the uterine cervix: Schistosoma hematobium calcified eggs.
- Author
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Toller A, Scopin AC, Apfel V, Prigenzi KC, Tso FK, Focchi GR, Speck N, and Ribalta J
- Abstract
Schistosoma hematobium infection is an endemic parasitic disease in Africa, which is frequently associated with urinary schistosomiasis. The parasite infection causes epithelial changes and disruption, facilitating the infection by the human papilloma virus and human immunodeficiency virus (HIV). The authors report the case of a 44-year-old African HIV-positive woman who presented an abnormal routine Pap smear. Colposcopy examination revealed dense acetowhite micropapillary epithelium covering the ectocervix, iodine-negative, an erosion area in endocervical canal, and atypical vessels. Histologic examination of the surgical specimens showed numerous calcified schistosome eggs (probably S. hematobium) and a high-grade cervical intraepithelial neoplasia. The relation between S. hematobium infection and bladder cancer is well known; however, this relationship with cervical cancer remains controversial. The symptoms of schistosomiasis of the female genital tract are rather non-specific, and are often misdiagnosed with other pelvic diseases. The familiarity of health professionals with schistosomiasis of the female genital tract is less than expected, even in endemic regions. Therefore, great awareness of this differential diagnosis in routine gynecological practice is of paramount importance.
- Published
- 2015
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40. The Antiatherogenic Effect of Fish Oil in Male Mice Is Associated with a Diminished Release of Endothelial ADAM17 and ADAM10 Substrates.
- Author
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Speck N, Brandsch C, Schmidt N, Yazdekhasti N, Hirche F, Lucius R, Rimbach G, Stangl GI, and Reiss K
- Subjects
- ADAM Proteins genetics, ADAM10 Protein, ADAM17 Protein, Amyloid Precursor Protein Secretases genetics, Animals, Aorta drug effects, Aorta metabolism, Cholesterol, Dietary administration & dosage, Cholesterol, Dietary adverse effects, Diet, Western adverse effects, Dietary Fats administration & dosage, Endothelial Cells drug effects, Endothelial Cells metabolism, Endothelium, Vascular drug effects, Endothelium, Vascular metabolism, Intercellular Adhesion Molecule-1 metabolism, Liver drug effects, Liver metabolism, Male, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Transgenic, RNA, Messenger genetics, RNA, Messenger metabolism, Real-Time Polymerase Chain Reaction, Receptors, LDL genetics, Receptors, LDL metabolism, ADAM Proteins metabolism, Amyloid Precursor Protein Secretases metabolism, Atherosclerosis drug therapy, Atherosclerosis prevention & control, Dietary Supplements, Fish Oils pharmacology, Membrane Proteins metabolism
- Abstract
Background: Growing evidence suggests that disintegrin and metalloprotease (ADAM) 17 (ADAM17) and ADAM10 contribute to the pathogenesis of vascular diseases. ADAM17 promotes inflammatory processes by liberating tumor necrosis factor α, interleukin 6 receptor (IL-6R), and tumor necrosis factor receptor 1 (TNFR1). ADAM17 and ADAM10 modulate vascular permeability by cleaving endothelial adhesion molecules such as junctional adhesion molecule A (JAM-A) and vascular endothelial cadherin (VE-cadherin), respectively., Objective: This study was designed to investigate whether a link might exist between the protective effects of fish oil (FO) supplementation against atherosclerosis and ADAM function., Methods: Male LDL receptor knockout (LDLR(-/-)) mice and male wild-type (WT) mice were fed a Western diet (200 g/kg fat, 1.5 g/kg cholesterol) containing either 20% lard (LDLR(-/-)-lard and WT-lard groups) or 10% lard combined with 10% FO (LDLR(-/-)-FO and WT-FO groups) for 12 wk. Atherosclerotic lesion development and fatty acid composition of liver microsomes were evaluated. ADAM10 and ADAM17 expression was determined by quantitative real-time polymerase chain reaction and immunoblot analyses. Concentrations of soluble ADAM substrates in plasma and liver extracts were measured by ELISA., Results: Diets supplemented with FO markedly reduced development of early atherosclerotic lesions in LDLR(-/-) mice (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 29.6 ± 6.1% vs. 22.5 ± 4.2%, P < 0.05). This was not accompanied by changes in expression of ADAM17 or ADAM10 in the aorta or liver. No dietary effects on circulating TNFR1 (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 1.22 ± 0.23 vs. 1.39 ± 0.28, P > 0.2) or IL-6R (1.06 ± 0.12 vs. 0.98 ± 0.09 fold of WT-lard group, P > 0.1), classical substrates of ADAM17 on macrophages, and neutrophil granulocytes were observed. However, a reduction in atherosclerotic lesions in the LDLR(-/-)-FO group was accompanied by a significant reduction in the circulating endothelial cell adhesion molecules JAM-A (LDLR(-/-)-lard group vs. LDLR(-/-)-FO group mean ± SD: 1.42 ± 0.20 vs. 0.95 ± 0.56 fold of WT-lard group, P < 0.05), intercellular adhesion molecule 1 (1.15 ± 0.14 vs. 0.88 ± 0.17 fold of WT-lard group, P < 0.05), and VE-cadherin (0.88 ± 0.12 vs. 0.72 ± 0.15 fold of WT-lard group, P < 0.05), reflecting reduced ADAM activity in endothelial cells., Conclusion: FO exerted an antiatherogenic effect on male LDLR(-/-) mice that was accompanied by a reduced release of ADAM17 and ADAM10 substrates from endothelial cells. It is suggested that FO-decreased ADAM activity contributes to improved endothelial barrier function and thus counteracts intimal lipoprotein insudation and macrophage accumulation., (© 2015 American Society for Nutrition.)
- Published
- 2015
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41. The cytoplasmic domain of a disintegrin and metalloproteinase 10 (ADAM10) regulates its constitutive activity but is dispensable for stimulated ADAM10-dependent shedding.
- Author
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Maretzky T, Evers A, Le Gall S, Alabi RO, Speck N, Reiss K, and Blobel CP
- Subjects
- ADAM Proteins chemistry, ADAM Proteins genetics, ADAM10 Protein, Amino Acid Sequence, Amyloid Precursor Protein Secretases chemistry, Amyloid Precursor Protein Secretases genetics, Animals, Base Sequence, Cells, Cultured, DNA Primers, Endoplasmic Reticulum metabolism, Membrane Proteins chemistry, Membrane Proteins genetics, Mice, Mice, Knockout, Molecular Sequence Data, Proteolysis, Real-Time Polymerase Chain Reaction, ADAM Proteins physiology, Amyloid Precursor Protein Secretases physiology, Cytoplasm enzymology, Membrane Proteins physiology
- Abstract
The membrane-anchored metalloproteinase a disintegrin and metalloprotease 10 (ADAM10) is required for shedding of membrane proteins such as EGF, betacellulin, the amyloid precursor protein, and CD23 from cells. ADAM10 is constitutively active and can be rapidly and post-translationally enhanced by several stimuli, yet little is known about the underlying mechanism. Here, we use ADAM10-deficient cells transfected with wild type or mutant ADAM10 to address the role of its cytoplasmic and transmembrane domain in regulating ADAM10-dependent protein ectodomain shedding. We report that the cytoplasmic domain of ADAM10 negatively regulates its constitutive activity through an ER retention motif but is dispensable for its stimulated activity. However, chimeras with the extracellular domain of ADAM10 and the transmembrane domain of ADAM17 with or without the cytoplasmic domain of ADAM17 show reduced stimulated shedding of the ADAM10 substrate betacellulin, whereas the ionomycin-stimulated shedding of the ADAM17 substrates CD62-L and TGFα is not affected. Moreover, we show that influx of extracellular calcium activates ADAM10 but is not essential for its activation by APMA and BzATP. Finally, the rapid stimulation of ADAM10 is not significantly affected by incubation with proprotein convertase inhibitors for up to 8 h, arguing against a major role of increased prodomain removal in the rapid stimulation of ADAM10. Thus, the cytoplasmic domain of ADAM10 negatively influences constitutive shedding through an ER retention motif, whereas the cytoplasmic domain and prodomain processing are not required for the rapid activation of ADAM10-dependent shedding events., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)
- Published
- 2015
- Full Text
- View/download PDF
42. The Notch1 transcriptional activation domain is required for development and reveals a novel role for Notch1 signaling in fetal hematopoietic stem cells.
- Author
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Gerhardt DM, Pajcini KV, D'altri T, Tu L, Jain R, Xu L, Chen MJ, Rentschler S, Shestova O, Wertheim GB, Tobias JW, Kluk M, Wood AW, Aster JC, Gimotty PA, Epstein JA, Speck N, Bigas A, and Pear WS
- Subjects
- Animals, Cell Line, Fetal Stem Cells, Gene Knock-In Techniques, Gene Knockout Techniques, Hematopoietic Stem Cells metabolism, Immunoglobulin J Recombination Signal Sequence-Binding Protein genetics, Immunoglobulin J Recombination Signal Sequence-Binding Protein metabolism, Mice, Mutation, Protein Structure, Tertiary genetics, Receptor, Notch1 genetics, Survival Analysis, Gene Expression Regulation, Developmental, Hematopoietic Stem Cells physiology, Receptor, Notch1 metabolism, Signal Transduction
- Abstract
Notch1 is required to generate the earliest embryonic hematopoietic stem cells (HSCs); however since Notch-deficient embryos die early in gestation, additional functions for Notch in embryonic HSC biology have not been described. We used two complementary genetic models to address this important biological question. Unlike Notch1-deficient mice, mice lacking the conserved Notch1 transcriptional activation domain (TAD) show attenuated Notch1 function in vivo and survive until late gestation, succumbing to multiple cardiac abnormalities. Notch1 TAD-deficient HSCs emerge and successfully migrate to the fetal liver but are decreased in frequency by embryonic day 14.5. In addition, TAD-deficient fetal liver HSCs fail to compete with wild-type HSCs in bone marrow transplant experiments. This phenotype is independently recapitulated by conditional knockout of Rbpj, a core Notch pathway component. In vitro analysis of Notch1 TAD-deficient cells shows that the Notch1 TAD is important to properly assemble the Notch1/Rbpj/Maml trimolecular transcription complex. Together, these studies reveal an essential role for the Notch1 TAD in fetal development and identify important cell-autonomous functions for Notch1 signaling in fetal HSC homeostasis.
- Published
- 2014
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- View/download PDF
43. HIF1α is a regulator of hematopoietic progenitor and stem cell development in hypoxic sites of the mouse embryo.
- Author
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Imanirad P, Solaimani Kartalaei P, Crisan M, Vink C, Yamada-Inagawa T, de Pater E, Kurek D, Kaimakis P, van der Linden R, Speck N, and Dzierzak E
- Subjects
- Animals, Aorta cytology, Cadherins metabolism, Cell Separation, Embryo, Mammalian cytology, Embryo, Mammalian metabolism, Embryo, Mammalian pathology, Endothelial Cells cytology, Endothelial Cells metabolism, Female, Fetus cytology, Hematopoietic Stem Cell Transplantation, Hypoxia-Inducible Factor 1, alpha Subunit deficiency, Hypoxia-Inducible Factor 1, alpha Subunit genetics, Liver cytology, Mice, Mice, Inbred C57BL, Placenta cytology, Pregnancy, Transplantation, Homologous, Cell Hypoxia physiology, Hematopoietic Stem Cells cytology, Hypoxia-Inducible Factor 1, alpha Subunit metabolism
- Abstract
Hypoxia affects many physiologic processes during early stages of mammalian ontogeny, particularly placental and vascular development. In the adult, the hypoxic bone marrow microenvironment plays a role in regulating hematopoietic stem cell (HSC) function. HSCs are generated from the major vasculature of the embryo, but whether the hypoxic response affects the generation of these HSCs is as yet unknown. Here we examined whether Hypoxia Inducible Factor1-alpha (HIF1α), a key modulator of the response to hypoxia, is essential for HSC development. We found hypoxic cells in embryonic tissues that generate and expand hematopoietic cells (aorta, placenta and fetal liver), and specifically aortic endothelial and hematopoietic cluster cells. A Cre/loxP conditional knockout (cKO) approach was taken to delete HIF1α in Vascular Endothelial-Cadherin expressing endothelial cells, the precursors to definitive hematopoietic cells. Functional assays show that HSC and hematopoietic progenitor cells (HPCs) are significantly reduced in cKO aorta and placenta. Moreover, decreases in phenotypic aortic hematopoietic cluster cells in cKO embryos indicate that HIF1α is necessary for generation and/or expansion of HPCs and HSCs. cKO adult BM HSCs are also affected under transplantation conditions. Thus, HIF1α is a regulator of HSC generation and function beginning at the earliest embryonic stages., (© 2013 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
44. Gata2 is required for HSC generation and survival.
- Author
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de Pater E, Kaimakis P, Vink CS, Yokomizo T, Yamada-Inagawa T, van der Linden R, Kartalaei PS, Camper SA, Speck N, and Dzierzak E
- Subjects
- Alleles, Animals, Apoptosis, Cell Separation, Cell Survival, Flow Cytometry, Gene Deletion, Mice, Mice, Knockout, Mice, Transgenic, Stem Cells, GATA2 Transcription Factor physiology, Gene Expression Regulation, Developmental, Hematopoietic Stem Cells cytology
- Abstract
Knowledge of the key transcription factors that drive hematopoietic stem cell (HSC) generation is of particular importance for current hematopoietic regenerative approaches and reprogramming strategies. Whereas GATA2 has long been implicated as a hematopoietic transcription factor and its dysregulated expression is associated with human immunodeficiency syndromes and vascular integrity, it is as yet unknown how GATA2 functions in the generation of HSCs. HSCs are generated from endothelial cells of the major embryonic vasculature (aorta, vitelline, and umbilical arteries) and are found in intra-aortic hematopoietic clusters. In this study, we find that GATA2 function is essential for the generation of HSCs during the stage of endothelial-to-hematopoietic cell transition. Specific deletion of Gata2 in Vec (Vascular Endothelial Cadherin)-expressing endothelial cells results in a deficiency of long-term repopulating HSCs and intra-aortic cluster cells. By specific deletion of Gata2 in Vav-expressing hematopoietic cells (after HSC generation), we further show that GATA2 is essential for HSC survival. This is in contrast to the known activity of the RUNX1 transcription factor, which functions only in the generation of HSCs, and highlights the unique requirement for GATA2 function in HSCs throughout all developmental stages.
- Published
- 2013
- Full Text
- View/download PDF
45. Melittin modulates keratinocyte function through P2 receptor-dependent ADAM activation.
- Author
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Sommer A, Fries A, Cornelsen I, Speck N, Koch-Nolte F, Gimpl G, Andrä J, Bhakdi S, and Reiss K
- Subjects
- ADAM Proteins genetics, ADAM10 Protein, ADAM17 Protein, Adenosine Triphosphate metabolism, Amyloid Precursor Protein Secretases genetics, Amyloid Precursor Protein Secretases metabolism, Animals, Blotting, Western, Cadherins metabolism, Cell Line, Cell Survival drug effects, Cells, Cultured, Dose-Response Relationship, Drug, Embryo, Mammalian cytology, ErbB Receptors metabolism, Extracellular Signal-Regulated MAP Kinases metabolism, Fibroblasts cytology, Fibroblasts drug effects, Fibroblasts metabolism, HEK293 Cells, Humans, Keratinocytes cytology, Keratinocytes metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Mice, Knockout, Models, Biological, Phosphorylation drug effects, Receptors, Purinergic P2X7 genetics, Reverse Transcriptase Polymerase Chain Reaction, ADAM Proteins metabolism, Keratinocytes drug effects, Melitten pharmacology, Receptors, Purinergic P2X7 metabolism
- Abstract
Melittin, the major component of the bee venom, is an amphipathic, cationic peptide with a wide spectrum of biological properties that is being considered as an anti-inflammatory and anti-cancer agent. It modulates multiple cellular functions but the underlying mechanisms are not clearly understood. Here, we report that melittin activates disintegrin-like metalloproteases (ADAMs) and that downstream events likely contribute to the biological effects evoked by the peptide. Melittin stimulated the proteolysis of ADAM10 and ADAM17 substrates in human neutrophil granulocytes, endothelial cells and murine fibroblasts. In human HaCaT keratinocytes, melittin induced shedding of the adhesion molecule E-cadherin and release of TGF-α, which was accompanied by transactivation of the EGF receptor and ERK1/2 phosphorylation. This was followed by functional consequences such as increased keratinocyte proliferation and enhanced cell migration. Evidence is provided that ATP release and activation of purinergic P2 receptors are involved in melittin-induced ADAM activation. E-cadherin shedding and EGFR phosphorylation were dose-dependently reduced in the presence of ATPases or P2 receptor antagonists. The involvement of P2 receptors was underscored in experiments with HEK cells, which lack the P2X7 receptor and showed strikingly increased response to melittin stimulation after transfection with this receptor. Our study provides new insight into the mechanism of melittin function which should be of interest particularly in the context of its potential use as an anti-inflammatory or anti-cancer agent.
- Published
- 2012
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46. A novel RUNX2 missense mutation predicted to disrupt DNA binding causes cleidocranial dysplasia in a large Chinese family with hyperplastic nails.
- Author
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Tang S, Xu Q, Xu X, Du J, Yang X, Jiang Y, Wang X, Speck N, and Huang T
- Subjects
- Adult, China, Female, Humans, Hyperplasia, Male, Nails, Malformed pathology, Pedigree, Cleidocranial Dysplasia genetics, Core Binding Factor Alpha 1 Subunit genetics, DNA-Binding Proteins genetics, Mutation, Missense, Nails, Malformed genetics
- Abstract
Background: Cleidocranial dysplasia (CCD) is a dominantly inherited disease characterized by hypoplastic or absent clavicles, large fontanels, dental dysplasia, and delayed skeletal development. The purpose of this study is to investigate the genetic basis of Chinese family with CCD., Methods: Here, a large Chinese family with CCD and hyperplastic nails was recruited. The clinical features displayed a significant intrafamilial variation. We sequenced the coding region of the RUNX2 gene for the mutation and phenotype analysis., Results: The family carries a c.T407C (p.L136P) mutation in the DNA- and CBFbeta-binding Runt domain of RUNX2. Based on the crystal structure, we predict this novel missense mutation is likely to disrupt DNA binding by RUNX2, and at least locally affect the Runt domain structure., Conclusion: A novel missense mutation was identified in a large Chinese family with CCD with hyperplastic nails. This report further extends the mutation spectrum and clinical features of CCD. The identification of this mutation will facilitate prenatal diagnosis and preimplantation genetic diagnosis.
- Published
- 2007
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- View/download PDF
47. Nomenclature for Runt-related (RUNX) proteins.
- Author
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van Wijnen AJ, Stein GS, Gergen JP, Groner Y, Hiebert SW, Ito Y, Liu P, Neil JC, Ohki M, and Speck N
- Subjects
- Animals, Core Binding Factor Alpha 2 Subunit, Core Binding Factor Alpha 3 Subunit, Core Binding Factor alpha Subunits, DNA-Binding Proteins genetics, Humans, Neoplasm Proteins genetics, Protein Isoforms genetics, Proto-Oncogene Proteins genetics, Transcription Factors genetics, DNA-Binding Proteins classification, Neoplasm Proteins classification, Proto-Oncogene Proteins classification, Terminology as Topic, Transcription Factors classification
- Published
- 2004
- Full Text
- View/download PDF
48. Runx1 is essential for hematopoietic commitment at the hemangioblast stage of development in vitro.
- Author
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Lacaud G, Gore L, Kennedy M, Kouskoff V, Kingsley P, Hogan C, Carlsson L, Speck N, Palis J, and Keller G
- Subjects
- Animals, Cell Differentiation genetics, Core Binding Factor Alpha 2 Subunit, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Embryo, Mammalian embryology, Embryo, Mammalian metabolism, Erythropoiesis drug effects, Flow Cytometry, Gene Expression Profiling, Gene Expression Regulation, Developmental physiology, Hematopoietic Stem Cells metabolism, Mice, RNA, Messenger analysis, Transcription Factors genetics, Transcription Factors metabolism, Yolk Sac cytology, DNA-Binding Proteins physiology, Embryo, Mammalian cytology, Hematopoiesis drug effects, Proto-Oncogene Proteins, Transcription Factors physiology
- Abstract
In this report we demonstrate a role for Runx1 (AML1) at the hemangioblast stage of hematopoietic and endothelial development in embryonic stem (ES) cell-derived embryoid bodies (EBs). Runx1 is expressed in EBs during the appearance of precursors with hemangioblast properties, the blast colony-forming cells (BL-CFCs). Cell sorting studies revealed that all BL-CFCs within EBs express Runx1. Runx1-deficient EBs consistently generate 10- to 20-fold fewer blast colonies than wild-type controls and display a complete block in definitive hematopoiesis. Despite this defect, Runx1-/- EBs and yolk sacs from mutant embryos generate normal numbers of primitive erythroid precursors. These observations clearly demonstrate that Runx1 functions early in hematopoietic development, and they support the interpretation that the primitive erythroid lineage is established early by a subset of BL-CFCs that develop in a Runx1-independent fashion.
- Published
- 2002
- Full Text
- View/download PDF
49. Spatial and temporal expression pattern of Runx3 (Aml2) and Runx1 (Aml1) indicates non-redundant functions during mouse embryogenesis.
- Author
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Levanon D, Brenner O, Negreanu V, Bettoun D, Woolf E, Eilam R, Lotem J, Gat U, Otto F, Speck N, and Groner Y
- Subjects
- Animals, Bone Development, Bone and Bones metabolism, Core Binding Factor Alpha 2 Subunit, Hematopoietic System embryology, Immunohistochemistry, Mice, Time Factors, Tissue Distribution, DNA-Binding Proteins biosynthesis, Neoplasm Proteins, Proto-Oncogene Proteins, Transcription Factors biosynthesis
- Abstract
The human RUNX3/AML2 gene belongs to the 'runt domain' family of transcription factors that act as gene expression regulators in major developmental pathways. Here, we describe the expression pattern of Runx3 during mouse embryogenesis compared to the expression pattern of Runx1. E10.5 and E14.5-E16.5 embryos were analyzed using both immunohistochemistry and beta-galactosidase activity of targeted Runx3 and Runx1 loci. We found that Runx3 expression overlapped with that of Runx1 in the hematopoietic system, whereas in sensory ganglia, epidermal appendages, and developing skeletal elements, their expression was confined to different compartments. These data provide new insights into the function of Runx3 and Runx1 in organogenesis and support the possibility that cross-regulation between them plays a role in embryogenesis.
- Published
- 2001
- Full Text
- View/download PDF
50. Core-binding factor beta (CBFbeta), but not CBFbeta-smooth muscle myosin heavy chain, rescues definitive hematopoiesis in CBFbeta-deficient embryonic stem cells.
- Author
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Miller JD, Stacy T, Liu PP, and Speck NA
- Subjects
- Animals, Cell Differentiation, Chromosome Inversion, Colony-Forming Units Assay, Core Binding Factor Alpha 2 Subunit, Core Binding Factor beta Subunit, DNA-Binding Proteins chemistry, DNA-Binding Proteins genetics, Dimerization, Genes, Lethal, Genetic Complementation Test, Hematopoiesis genetics, Leukemia, Myelomonocytic, Acute genetics, Mice, Mice, Knockout, Myeloid Cells cytology, Myeloid Cells metabolism, Oncogene Proteins, Fusion chemistry, Oncogene Proteins, Fusion genetics, Protein Structure, Tertiary, Protein Subunits, Recombinant Fusion Proteins physiology, Stem Cells cytology, Structure-Activity Relationship, Transcription Factor AP-2, Transcription Factors chemistry, Transcription Factors genetics, Transfection, Transgenes, DNA-Binding Proteins physiology, Hematopoiesis physiology, Oncogene Proteins, Fusion physiology, Proto-Oncogene Proteins, Stem Cells metabolism, Transcription Factors physiology
- Abstract
Core-binding factor beta (CBFbeta) is the non-DNA-binding subunit of the heterodimeric CBFs. Genes encoding CBFbeta (CBFB), and one of the DNA-binding CBFalpha subunits, Runx1 (also known as CBFalpha2, AML1, and PEBP2alphaB), are required for normal hematopoiesis and are also frequent targets of chromosomal translocations in acute leukemias in humans. Homozygous disruption of either the Runx1 or Cbfb gene in mice results in embryonic lethality at midgestation due to hemorrhaging in the central nervous system, and severely impairs fetal liver hematopoiesis. Results of this study show that Cbfb-deficient mouse embryonic stem (ES) cells can differentiate into primitive erythroid colonies in vitro, but are impaired in their ability to produce definitive erythroid and myeloid colonies, mimicking the in vivo defect. Definitive hematopoiesis is restored by ectopic expression of full-length Cbfb transgenes, as well as by a transgene encoding only the heterodimerization domain of CBFbeta. In contrast, the CBFbeta-smooth muscle myosin heavy chain (SMMHC) fusion protein generated by the inv(16) associated with acute myeloid leukemias (M4Eo) cannot rescue definitive hematopoiesis by Cbfb-deficient ES cells. Sequences responsible for the inability of CBFbeta-SMMHC to rescue definitive hematopoiesis reside in the SMMHC portion of the fusion protein. Results also show that the CBFbeta-SMMHC fusion protein transdominantly inhibits definitive hematopoiesis, but not to the same extent as homozygous loss of Runx1 or Cbfb. CBFbeta-SMMHC preferentially inhibits the differentiation of myeloid lineage cells, while increasing the number of blastlike cells in culture.
- Published
- 2001
- Full Text
- View/download PDF
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