Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 41 )

2018 ( 363 )

2017 ( 366 )

2016 ( 490 )

Custom range...

Search Results: 1 - 10 of 212733 matches for " P. Nguyen-Tan "
All listed articles are free for downloading (OA Articles)
Page 1 /212733
Display every page Item
HPV Prevalence and Prognostic Value in a Prospective Cohort of 255 Patients with Locally Advanced HNSCC: A Single-Centre Experience
E. Thibaudeau,B. Fortin,F. Coutlée,P. Nguyen-Tan,X. Weng,M.-L. Audet,O. Abboud,L. Guertin,A. Christopoulos,J. Tabet,D. Soulières
International Journal of Otolaryngology , 2013, DOI: 10.1155/2013/437815
Abstract: Background. HPV is a positive prognostic factor in HNSCC. We studied the prevalence and prognostic impact of HPV on survival parameters and treatment toxicity in patients with locally advanced HNSCC treated with concomitant chemoradiation therapy. Methods. Data on efficacy and toxicity were available for 560 patients. HPV was detected by PCR. Analysis was performed using Kaplan-Meier survival curves, Fisher’s test for categorical data, and log-rank statistics for failure times. Results. Median follow-up was 4.7 years. DNA extraction was successful in 255 cases. HPV prevalence was 68.6%, and 53.3% for HPV 16. For HPV+ and HPV?, median LRC was 8.9 and 2.2 years ( ), median DFS was 8.9 and 2.1 years ( ), and median OS was 8.9 and 3.1 years ( ). Survival was different based on HPV genotype, stage, treatment period, and chemotherapy regimen. COX adjusted analysis for T, N, age, and treatment remained significant ( ). Conclusions. Oropharyngeal cancer is increasingly linked to HPV. This study confirms that HPV status is associated with improved prognosis among H&N cancer patients receiving CRT and should be a stratification factor for clinical trials including H&N cases. Toxicity of CRT is not modified for the HPV population. 1. Introduction Tobacco and alcohol consumption has long been known as the major risk factor for HNSCC. However, HPV has recently been recognised to play a role in the pathogenesis of a subset of clinically and molecularly distinct HNSCC, most often located in the oropharynx and associated with wild-type p53 and downregulation of cyclin D and retinoblastoma protein pRb [1–5], and in which viral oncoproteins E6 and E7 play a crucial part [6]. HPV prevalence in HNSCC has been increasing significantly in the past few decades [5, 7]; it is estimated at 25% in HNSCC [8], but reaches up to 70% or more in tonsillar SCCs [9–11]. Unlike the HPV-negative oropharyngeal cancers, the HPV-positive subset is not associated with tobacco or alcohol use, but with certain types of sexual behaviours [12, 13]. The HPV 16 subtype is present in up to 90% of HPV-related oropharyngeal cancers, while HPVs 18, 31, and 33 have been identified in the remainder [14, 15]. HPV has recently been recognised as a good prognostic factor in head and neck (H&N) cancer [5, 16–26], which has been attributed to several mechanisms, including absence of field cancerisation and increased sensitivity to chemoradiation therapy [5, 16, 20, 22–24, 26]. Most of the available data is derived from small randomised trials with different treatment options or small heterogeneous cohorts;
Prevalence of K-RAS Codons 12 and 13 Mutations in Locally Advanced Head and Neck Squamous Cell Carcinoma and Impact on Clinical Outcomes
Eric Bissada,Olivier Abboud,Zahi Abou Chacra,Louis Guertin,Xiaoduan Weng,Phuc Félix Nguyen-Tan,Jean-Claude Tabet,ève Thibaudeau,Louise Lambert,Marie-Lise Audet,Bernard Fortin,Denis Soulières
International Journal of Otolaryngology , 2013, DOI: 10.1155/2013/848021
Abstract: Background. RAS gene mutations have an impact on treatment response and overall prognosis for certain types of cancer. Objectives. To determine the prevalence and impact of K-RAS codons 12 and 13 mutations in patients with locally advanced HNSCC treated with primary or adjuvant chemo-radiation. Methods. 428 consecutive patients were treated with chemo-radiation therapy and followed for a median of 37 months. From these, 199 paraffin embedded biopsy or surgical specimens were retrieved. DNA was isolated and analyzed for K-RAS mutational status. Results. DNA extraction was successful in 197 samples. Of the 197 specimens, 3.5% presented K-RAS codon 12 mutations. For mutated cases and non-mutated cases, complete initial response to chemoradiation therapy was 71 and 73% ( ). LRC was respectively 32 and 83% ( ), DFS was 27 and 68% ( ), distant metastasis-free survival was 100 and 81% ( ) and OS was 57 and 65% ( ) at three years. K-Ras codon 13 analysis revealed no mutation. Conclusion. K-RAS codon 12 mutational status, although not associated with a difference in response rate, may influence the failure pattern and the type of therapy offered to patients with HNSCC. Our study did not reveal any mutation of K-RAS codon 13. 1. Introduction Head and neck squamous cell carcinoma (HNSCC) accounts for 47?000 new malignancies diagnosed each year in the USA and is the sixth most common human neoplasm, representing about 3% of all cancers [1]. Despite efforts to improve conventional treatment, survival rates for these cancers have not changed significantly over the past decade. Initial evaluation of patients includes clinical assessment, study of tumor histological characteristics and tumor grading, as well as local-regional and distant metastasis status. Traditional clinical, radiological, and histopathological characteristics are however limited in their ability to accurately predict response to treatment. This has motivated many researchers to identify molecular characteristics that may influence overall prognosis. A recent interest in molecular biology and genetics is motivated by the belief that understanding the origins of cancer can lead to more logical means of treating malignancies [2]. Identification of molecular events that lead to HNSCC may represent a key to predicting biological behaviour and may consequently lead to new treatment modalities that could lead to increases in survival rates. [3, 4]. Despite the recent progress in the field of molecular biology, clinicians need more tools to predict response to therapy or to identify patients at high risk of
Challenges of Energy Security to the Industrialisation and Sustainable Development in Vietnam  [PDF]
Nguyen Tan Phat
Technology and Investment (TI) , 2012, DOI: 10.4236/ti.2012.33024
Abstract: Vietnam, during the industrialisation, has been facing the problem of energy security, the manifestation of which is lack of electricity on a large scale, affecting the growth of production and people’s lives. In the past years, the fact that energy development has depended mainly on hydroelectricity and thermo-electricity but taken little care of clean energy has been opening up problems related to environment and sustainable development. Thus, at the same time, Energy Branch has to tackle 2 issues. The first is meeting the demand of energy for industrialization and social-economic growth. The second is developing sustainable energy, particularly safe and renewable power.
Motivations and Barriers of the Model of Non-Traditional Market Economy: A Case to Study in BRICS  [PDF]
Nguyen Tan Phat
Modern Economy (ME) , 2012, DOI: 10.4236/me.2012.38115
Abstract: Emerging economies including Brasil,Russia,India,ChinaandSouth Africaknown as a growing force with the power of economy, finance and enormous potentials are considered as massive motivations affecting greatly the rest parts of the entire world. Theirs characteristics of politics, political geography and economic policy are not identical to traditional market economies inEuropeand the U.S. BRICS can be called the model of non-traditional market economy.The rise and the great effect of BRICS can change the order of the current world which has long been dominated by western nations during the past 2 decades. However, BRICS itself contains challenges and barriers for the socio-economic development such as hot growth, poverty, low living standards and enviromental pollution, etc. The political affiliations and violence in declaring the sovereignty of seas, islands and territory reveal the latent unstability that can drive to conflicts and arms race, etc.Brics is a force without lack of necessary motivational factors that can enhance the development but also contain inside challenges and barriers for the rest parts of the modern world.
Administrative Reforms of Rural Land in Transition Economies: An Example in China and Vietnam  [PDF]
Nguyen Tan Phat
Sociology Mind (SM) , 2013, DOI: 10.4236/sm.2013.31009

The administrative issue of rural land has been filled with little concern by the State and scientists but have had a great impact on rural community’s life in organization of agricultural production, space for living and the guarantee of rights of land assets of farmers. Moreover, it also has a direct effect on the State’s managerial efficiency in rural areas. Vietnam and China have some common points in politics, particularly in policies of farm land and the process of reforms in rural land as well. This article is about China’s experience and Vietnam’s reality in the economic transition period. Such matters of administrative reforms in rural land in Vietnam and China can be referential lessons for nations with the same circumstances.


On Galois cohomology of unipotent algebraic groups over local fields
Nguyen Duy Tan
Mathematics , 2009,
Abstract: In this paper, we give a necessary and sufficient condition for the finiteness of Galois cohomology of unipotent groups over local fields of positive characteristic
On the essential dimension of unipotent algebraic groups
Nguyen Duy Tan
Mathematics , 2010,
Abstract: We give an upper bound for the essential dimension of a smooth unipotent algebraic group over an arbitrary field. We also show that over a field $k$ which is finitely generated over a perfect field, a smooth unipotent algebraic $k$-group is of essential dimension 0 if and only if it is $k$-split.
Embedding problems with local conditions and the admissibility of finite groups
Nguyen Duy Tan
Mathematics , 2011,
Abstract: Let $k$ be a field of characteristic $p>0$, which has infinitely many discrete valuations. We show that every finite embedding problem for $\Gal(k)$ with finitely many prescribed local conditions, whose kernel is a $p$-group, is properly solvable. We then apply this result in studying the admissibility of finite groups over global fields of positive characteristic. We also give another proof for a result of Sonn.
Gamma Cascade Transition of 51V(nth, g )52V Reaction  [PDF]
Pham Dinh Khang, Nguyen Xuan Hai, Ho Huu Thang, Vuong Huu Tan, Nguyen An Son, Nguyen Duc Hoa
World Journal of Nuclear Science and Technology (WJNST) , 2014, DOI: 10.4236/wjnst.2014.41007

The thermal neutron capture gamma radiations for 51V(n, g)52V reaction have been studied at Dalat Nuclear Research Reactor (DNRR). The gamma two-step cascade transition was measured by event-event coincidence spectrometer. The added-neutron binding energy in 52V was measured as 7.31 MeV. Energy and the intensity transition of cascades were consistent with prediction of single particle model. Furthermore, the spin and the parity of levels were confined.

Counting Galois ${\mathbb U}_4({\mathbb F}_p)$-extensions using Massey products
Jan Minac,Nguyen Duy Tan
Mathematics , 2014,
Abstract: We use Massey products and their relations to unipotent representations to parametrize and find an explicit formula for the number of Galois extensions of a given local field with the prescribed Galois group ${\mathbb U}_4({\mathbb F}_p)$ consisting of unipotent four by four matrices over ${\mathbb F}_p$. Further applications of this method involve the counting of certain Galois extensions with restricted ramifications, and counting the numbers of Galois ${\mathbb U}_4({\mathbb F}_p)$-extensions of some other fields. For each Demushkin pro-$p$-group, we find a very simple version of the condition when the $n$-fold Massey product of one-dimensional cohomological elements of $G$ with coefficients in ${\mathbb F}_p$, is defined. As an easy consequence, we determine those ${\mathbb U}_n({\mathbb F}_p)$ which occur as an epimorphic image of any given Demushkin group.
Page 1 /212733
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.