17 research outputs found
Theory of Stellar Oscillations
In recent years, astronomers have witnessed major progresses in the field of
stellar physics. This was made possible thanks to the combination of a solid
theoretical understanding of the phenomena of stellar pulsations and the
availability of a tremendous amount of exquisite space-based asteroseismic
data. In this context, this chapter reviews the basic theory of stellar
pulsations, considering small, adiabatic perturbations to a static, spherically
symmetric equilibrium. It starts with a brief discussion of the solar
oscillation spectrum, followed by the setting of the theoretical problem,
including the presentation of the equations of hydrodynamics, their
perturbation, and a discussion of the functional form of the solutions.
Emphasis is put on the physical properties of the different types of modes, in
particular acoustic (p-) and gravity (g-) modes and their propagation cavities.
The surface (f-) mode solutions are also discussed. While not attempting to be
comprehensive, it is hoped that the summary presented in this chapter addresses
the most important theoretical aspects that are required for a solid start in
stellar pulsations research.Comment: Lecture presented at the IVth Azores International Advanced School in
Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
Azores Islands, Portugal in July 201
Prospects for asteroseismology
The observational basis for asteroseismology is being dramatically
strengthened, through more than two years of data from the CoRoT satellite, the
flood of data coming from the Kepler mission and, in the slightly longer term,
from dedicated ground-based facilities. Our ability to utilize these data
depends on further development of techniques for basic data analysis, as well
as on an improved understanding of the relation between the observed
frequencies and the underlying properties of the stars. Also, stellar modelling
must be further developed, to match the increasing diagnostic potential of the
data. Here we discuss some aspects of data interpretation and modelling,
focussing on the important case of stars with solar-like oscillations.Comment: Proc. HELAS Workshop on 'Synergies between solar and stellar
modelling', eds M. Marconi, D. Cardini & M. P. Di Mauro, Astrophys. Space
Sci., in the press Revision: correcting abscissa labels on Figs 1 and
Common Missense Variant in the Glucokinase Regulatory Protein Gene Is Associated With Increased Plasma Triglyceride and C-Reactive Protein but Lower Fasting Glucose Concentrations
OBJECTIVEâUsing the genome-wide association approach, we recently identified the glucokinase regulatory protein gene (GCKR, rs780094) region as a novel quantitative trait locus for plasma triglyceride concentration in Europeans. Here, we sought to study the association of GCKR variants with metabolic phenotypes, including measures of glucose homeostasis, to evaluate the GCKR locus in samples of non-European ancestry and to fine- map across the associated genomic interval
Synovial Sarcoma of the Tongue: Case Report and Review of the Literature
[No abstract available
399 Expression patterns of vimentin and e-cadherin in ephitelial-mesenchymal transition: A potential prognostic factor in penile cancer
A Clinical, Pathologic, And Molecular Study Of P53 And Murine Double Minute 2 In Penile Carcinogenesis And Its Relation To Prognosis
Penile carcinoma constitutes up to 16% of male malignancies in developing countries. Changes in the P53 and murine double minute 2 pathway are important events in various cancers. Associate alterations in murine double minute 2 and P53 expression were evaluated by molecular techniques, with the clinical data of 297 cases of penile carcinoma. Automated immunohistochemistry was performed for murine double minute 2 and P53 using the primary antibodies SPM14 and DO7, respectively. Fluorescent in situ hybridization was performed using the probes murine double minute 2 at 12q15 and TP53 at 17p13.1. Slides were digitalized, and bright-field and fluorescent images were analyzed. TP53 was sequenced in 16 cases. The expression of P53 was higher in poorly differentiated, infiltrative border, corpus spongiosum, corpora cavernosa, and invasive urethral carcinomas. Patients who died of disease also expressed higher levels of P53. P53-negative tumors were associated with higher overall survival. Murine double minute 2 showed no difference of expression in any group of tumors, no correlation with P53 expression. No alterations in genes or chromosomes were observed. Mutations in TP53 were observed in 4 of 16 cases: p.T170M, p.L252P, p.C176Y, and the novel c.803-810del8; these changes correlated with P53 expression by immunohistochemistry. Murine double minute 2 is not useful in the prognosis of penile carcinoma by immunohistochemistry. Additional studies on the transcriptional, posttranscriptional, and epigenetic aspects are necessary to understand the interactions between P53 and murine double minute 2 because we did not observe any numeric alterations by fluorescent in situ hybridization. Examining P53 is helpful in identifying patients with more aggressive tumors and may be crucial in selecting the most suitable surgical procedure. © 2012 Elsevier Inc. All rights reserved.434481488Peclat De Paula, A.A., Netto, J.C.A., Cruz, A.D., JĂșnior, R.F., Carcinoma epidermĂłide do pĂȘnis: ConsideraçÔes epidemiolĂłgicas, histopatolĂłgicas, influĂȘncia viral e tratamento cirĂșrgico (2005) Rev Bras Cancerol, 51, pp. 243-252Dillner, J., Von Krogh, G., Horenblas, S., Meijer, C.J.L.M., Etiology of squamous cell carcinoma of the penis (2000) Scandinavian Journal of Urology and Nephrology, SUPPL.ement, 34 (205), pp. 189-193Wang, Y.C., Lin, R.K., Tan, Y.H., Chen, J.T., Chen, C.Y., Wang, Y.C., Wild-type P53 overexpression and its correlation with MDM2 and p14ARF alterations: An alternative pathway to non-small-cell lung cancer (2005) J Clin Oncol, 23, pp. 154-164Blagosklonny, M.V., P53 from complexity to simplicity: Mutant P53 stabilization, gain-of-function, and dominant-negative effect (2000) FASEB J, 14, pp. 1901-1907Fett-Conte, A.C., Salles, A.B.C.F., A importĂąncia do gene P53 na carcinogĂȘnese humana (2002) Rev Bras Hematol Hemoter, 24, pp. 85-89Chen, L., Yin, H., Farooqi, B., Sebti, S., Hamilton, A.D., Chen, J., P53 α-helix mimetics antagonize P53/MDM2 interaction and activate P53 (2005) Molecular Cancer Therapeutics, 4 (6), pp. 1019-1025. , DOI 10.1158/1535-7163.MCT-04-0342Dong, Y., Walsh, M.D., McGuckin, M.A., Cummings, M.C., Gabrielli, B.G., Wrigiit, G.R., Hurst, T., Parsons, P.G., Reduced expression of retinoblastoma gene product (pRB) and high expression of P53 are associated with poor prognosis in ovarian cancer (1997) International Journal of Cancer, 74 (4), pp. 407-415. , DOI 10.1002/(SICI)1097-0215(19970822)74:4<407::AID-IJC8>3.0.CO;2-ZFicarra, V., D'Amico, A., Cavalleri, S., Surgical treatment of penile carcinoma: Our experience from 1976 to 1997 (1999) Urol Int, 62, p. 234Lopes, A., Bezerra, A.L.R., Antonio, C., Pinto, L., Serrano, S.V., De Mello, C.A., Villa, L.L., P53 as a new prognostic factor for lymph node metastasis in penile carcinoma: Analysis of 82 patients treated with amputation and bilateral lymphadenectomy (2002) Journal of Urology, 168 (1), pp. 81-86Alarcon-Vargas, D., Ronai, Z., P53-Mdm2-the affair that never ends (2002) Carcinogenesis, 23 (4), pp. 541-547Ganguli, G., Abecassis, J., Wasylyk, B., MDM2 induces hyperplasia and premalignant lesions when expressed in the basal layer of the epidermis (2000) EMBO J, 19, pp. 5135-5147Ouban, A., Dellis, J., Salup, R., Morgan, M., Immunohistochemical expression of Mdm2 and P53 in penile verrucous carcinoma (2003) Annals of Clinical and Laboratory Science, 33 (1), pp. 101-106Wurl, P., Meye, A., Schmidt, H., Lautenschlager, C., Kalthoff, H., Rath, F.-W., Taubert, H., High prognostic significance of Mdm2/P53 co-overexpression in soft tissue sarcomas of the extremities (1998) Oncogene, 16 (9), pp. 1183-1185Cabelguenne, A., Blons, H., De Waziers, I., P53 alterations predict tumor response to neoadjuvant chemotherapy in head and neck squamous cell carcinoma: A prospective series (2000) J Clin Oncol, 18, p. 1465Cordon-Cardo, C., Zhang, Z.F., Dalbagni, G., Cooperative effects of P53 and pRB alterations in primary superficial bladder tumors (1997) Cancer Res, 57, p. 1217Jones, S., Sands, A., Hancock, A., Vogel, H., The tumorigenic potential and cell growth characteristics of P53-deficient cells are equivalent in the presence or absence of Mdm2A (1996) Proc Natl Acad Sci U S A, 93, pp. 14106-14111Jones, S.N., Hancock, A.R., Vogel, H., Donehower, L.A., Bradley, A., Overexpression of Mdm2 in mice reveals a P53-independent role for Mdm2 in tumorigenesis (1998) Proceedings of the National Academy of Sciences of the United States of America, 95 (26), pp. 15608-15612. , DOI 10.1073/pnas.95.26.15608Lev Bar-Or, R., Maya, R., Segel, L., Alon, U., Generation of oscillations by the P53-Mdm2 feedback loop: A theoretical and experimental study (2000) Proc Nat Acad Sci U S A, 97, pp. 11250-11255Li, L., Liao, J., Ruland, J., Mak, T.W., Cohen, S.N., A TSG101/MDM2 regulatory loop modulates MDM2 degradation and MDM2/P53 feedback control (2001) Proceedings of the National Academy of Sciences of the United States of America, 98 (4), pp. 1619-1624. , DOI 10.1073/pnas.98.4.1619Zhang, M.F., Zhang, Z.Y., Fu, J., Yang, Y.F., Yun, J.P., Correlation between expression of P53, p21/WAF1, and MDM2 proteins and their prognostic significance in primary hepatocellular carcinoma (2009) J Transl Med, 7, p. 110Maeda, K., Kang, S.-M., Onoda, N., Ogawa, M., Sawada, T., Nakata, B., Kato, Y., Sowa, M., Expression of P53 and vascular endothelial growth factor associated with tumor angiogenesis and prognosis in gastric cancer (1998) Oncology, 55 (6), pp. 594-599. , DOI 10.1159/000011918Brosh, R., Rotter, V., Transcriptional control of the proliferation cluster by the tumor suppressor P53 (2010) Mol Biosyst, 6, pp. 17-29Levine, A.J., Oren, M., The first 30 years of P53: Growing ever more complex (2009) Nat Rev Cancer, 9, pp. 749-75