199 research outputs found
Method for the Calculation of DPA in the Reactor Pressure Vessel of Atucha II
One of the limiting factors of the life of a nuclear power plant (NPP) is the state of the reactor pressure vessel (RPV). Embrittlement is the most important effect affecting RPV aging. The irradiation with neutrons, especially fast neutrons, is the primary cause of this embrittlement. NPP safe operation requires to ensure RPV integrity over its lifetime, threatened by the neutron radiation-induced embrittlement. In this paper, we identify the areas where the RPV neutron radiation is maximum and perform calculations of the displacement-per-atom (DPA) rate in those areas using the MCNP5 code.
It was determined that the maximum DPA rate in the RPV wall with fresh fuel element (FE) is 3.76(3) × 10-12 s-1, it takes place in front of FEs BA42 and BL43, and it is symmetrical about the central channel, LG04, and LH03
Use of information and communication technology and tools in the internazionalization department of a higher education institution
El uso de nuevas herramientas tecnológicas (TICS) es necesario a fin de que una Oficina de Proyectos internacionales trabaje de una manera más eficiente. Las TICS pueden usarse para apoyar la presentación de una propuesta (sitios para seguir los próximos llamados, herramientas para crear redes de trabajo) así como para el gerenciamiento del proyecto en sí (herramientas para gerenciar el proyecto, para desarrollar reuniones virtuales, para facilitar el trabajo virtual en equipos).Asimismo, las TICS favorecen la investigación (brindan acceso a información pública y especializada) y el entrenamiento (eLearning). Las comunicaciones internas y externas se ven mejoradas por las herramientas de comunicación sincrónicasy asincrónicas. La evaluación de las actividades se beneficia a través de las encuestas en línea, y la administración financiera de un proyecto se facilita con los sistemas contables. Las TICs están cambiando completamente la forma en que los proyectos internacionales se llevan adelante, haciendo posible y habituales realidades que antes eran inimaginables (por ejemplo, las reuniones virtuales). Este trabajo brinda una mirada a todos los posibles usos de las TICS en un Proyecto Internacional, y hace sugerencias sobre las herramientas a usar, basadas en la experiencia de los autores
Paraneoplastic Acanthosis Nigricans Maligna
Acanthosis Nigricans Maligna (ANM) is a paraneoplastic syndrome, defined as a condition that arises in association
with a malignancy elsewhere in the body but without malignant nature per se. It’s a rare dermatopathy that occurs in
men and women over age 40, without racial predilection or known familial association. Clinically, ANM showed symmetric,hyperpigmented plaques with variable amounts of epidermal hypertrophy, ranging in color from yellow to brown or black, often with overlaid papillomas. The most common affected sites are body flexures and the posterior neck, but also mucosal surface involvement is frequent and may be the only clinical symptom present. Any mucosal surface can be involved, and as regards the oral cavity, disease affects the lips, tongue, palate, buccal and gingival mucosa.ANM is primarily associated with adenocarcinomas, mostly of gastric origin. Accordingly, the progression of the tumor will lead to a worsening of the ANM, while regress in case of tumour treatment, and resurface with recurrence and metastases.
A 62-year-old man was referred for evaluation of papillomatous lesions of the oral mucosa, appeared in previous
months. The patient was diagnosed a gastric adenocarcinoma at an advanced stage 6 months before. Clinical examination showed diffuse papillomatous or wart-like areas of normal mucosal color and soft consistency involving lips,oral mucosa and hard palate. The tongue and the vestibular mucosa were thickened and furrowed. The lesions are
asymptomatic. A biopsy was performed, and histopathological analysis revealed acanthosis and papillomatosis, hyperkeratosis,and lymphohistiocytic infiltrate. The patient was clinically diagnosed with ANM, according to clinical and histologic findings, and the patient’s medical history. Isotretinoin 0,05% was prescribed for local therapy. The patient
did not return to follow-up due to complications of gastric adenocarcinoma, and died 6 months late
Trail Overexpression Inversely Correlates with Histological Differentiation in Intestinal-Type Sinonasal Adenocarcinoma
Introduction. Despite their histological resemblance to colorectal adenocarcinoma, there is some information about the molecular events involved in the pathogenesis of intestinal-type sinonasal adenocarcinomas (ITACs). To evaluate the possible role of TNF-related apoptosis-inducing ligand (TRAIL) gene defects in ITAC, by investigating the immunohistochemical expression of TRAIL gene product in a group of ethmoidal ITACs associated with occupational exposure. Material and Methods. Retrospective study on 23 patients with pathological diagnosis of primary ethmoidal ITAC. Representative formalin-fixed, paraffin-embedded block from each case was selected for immunohistochemical studies using the antibody against TRAIL. Clinicopathological data were also correlated with the staining results. Results. The immunohistochemical examination demonstrated that poorly differentiated cases showed a higher percentage of TRAIL expressing cells compared to well-differentiated cases. No correlation was found with other clinicopathological parameters, including T, stage and relapses. Conclusion. The relationship between upregulation of TRAIL and poorly differentiated ethmoidal adenocarcinomas suggests that the mutation of this gene, in combination with additional genetic events, could play a role in the pathogenesis of ITAC
Beyond head and neck cancer: The relationship between oral microbiota and tumour development in distant organs
An altered oral microbiota has been linked with the development of several oral diseases, such as dental caries, periodontal disease, and oral stomatitis. Moreover, poor oral health has been linked to head and neck cancer, particularly oral cancer. In recent years a growing number of studies indicate that oral microbiota could be involved in the development of primary tumours outside of head and neck region. The aim of this article is to review the recent studies based on high-throughput technology to present evidences of a relationship between oral microbiota and \u201cnon-head and neck tumours.\u201d Oral dysbiosis seem to be more pronounced in patients with tumours of gastrointestinal tract, in particular oesophageal, gastric, pancreatic, and colorectal cancers, paving the way for developing specific oral microbiota test to allow early cancer detection. Regarding other tumour types, the results are promising but highly preliminary and still debated. Currently, there are several factors that limit the generalization of the results, such as the small sample size, the lack of adequate clinical information about patients, the different sequencing techniques used, and biological sample heterogeneity. Although only at the beginning, the analysis of oral microbiota could be the next step in the evolution of cancer therapy and will help clinicians to develop individualised approaches to cancer prevention and treatment
Computational analysis of TP53 mutational landscape unveils key prognostic signatures and distinct pathobiological pathways in head and neck squamous cell cancer
Background: Mutations of the tumour-suppressor gene TP53 are the most frequent somatic genomic alterations in head and neck squamous cell carcinoma (HNSCC). However, it is not yet clear whether specific TP53 mutations bear distinct clinical and pathophysiological significance in different HNSCC subgroups. Methods: A systematic bioinformatics appraisal of TP53 mutations was performed on 415 HNSCC cases available on The Cancer Genome Atlas (TCGA). The following features were analysed and correlated with known clinicopathological variables: mutational profile of TP53, location (within secondary structure and predicted domains of p53 protein) and well-known hotspot mutations. Interactome–genome–transcriptome network analysis highlighted different gene networks. An algorithm was generated to develop a new prognostic classification system based on patients’ overall survival. Results: TP53 mutations in HNSCCs exhibited distinct differences in different anatomical sites. The mutational profile of TP53 was an independent prognostic factor in HNSCC. High risk of death mutations, identified by our novel classification algorithm, was an independent prognostic factor in TCGA HNSCC database. Finally, network analysis suggested that distinct p53 molecular pathways exist in a site- and mutation-specific manner. Conclusions: The mutational profile of TP53 may serve as an independent prognostic factor in HNSCC patients, and is associated with distinctive site-specific biological networks
Glandular odontogenic cyst: report of a new case with cytokeratin-19 expression
The glandular odontogenic cyst (GOC) was a rare jawbone cyst described in 1988 by Gardner et al.1 as a distinct entity. This lesion can involve either jaw, but the anterior region of the mandible was the most commonly affected area. Clinical and radiographic findings were not specific, and the diagnosis of GOC can be extremely difficult due to the rarity of this lesion. The cyst presented a wall constituted by fibrous connective tissue and was lined by a non-keratinized stratified squamous epithelium of variable thickness. Large areas of the lining epithelium presented cylinder cells, sometimes ciliated. A variable amount of mucina was occasionally noted. Due to the strong similarities, this cyst can be easily misdiagnosed as a central mucoepidermoid carcinoma (CMEC). Immunohistochemistry may be an aid in diagnosis; in fact Pires et al.2 have demonstrated that there were differences in the expression of cytokeratins (CK) in GOC and CMEC. In this study, we reported a new case of GOC in a 38-year-old female patient. The lesion was asymptomatic and was discovered as an incidental finding by a dentist some months before. Oral examination showed normal appearance and color of mucosa. Radiographic examination showed a well-defined, unilocular lesion extending in the left mandible anterior body, in an intraradicular position. The teeth were all vital. The lesion was subjected by surgical enucleation, and the material was sent for histopathological examination. Histopahological analysis of the lesion revealed cyst wall with focally ciliated epithelium lining of variable thickness. The superficial layer of the epithelium showed metaplastic mucous cell with intraepithelial microcystic area. The results of immunohistochemistry revealed strong positive activity for CK 19 in all layer of the epithelium. The postoperative course was uneventful, and there was no recurrence during the 18 months follow-up period
- …