288 research outputs found

    Povezanost između polimorfizama XRCC1 ARG399GLN i P53 ARG72PRO s rizikom od raka želuca i debeloga crijeva u turskoj populaciji

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    Gastric cancer is one of the most common cancers of the gastrointestinal system, and its overall fi ve-year survival rate is still 15 % to 20 %, as it can mostly be diagnosed at an advanced stage. On the other hand, although colorectal cancer has a rather good prognosis, mortality is one half that of the incidence. As carcinogenesis is believed to involve reactive radicals that cause DNA adduct formation, impaired repair activity, and weakened tumour suppression, it would help to understand the role of the polymorphisms of nucleotide excision repair enzyme XRCC1 and of tumour suppressor gene p53 in gastric and colorectal cancers. Our study included 94 gastric cancer patients, 96 colorectal cancer patients, and 108 cancer-free individuals as control with the aim to see if there was an association between XRCC1 Arg399Gln and p53 Arg72Pro polymorphisms and cancer susceptibility. DNA was extracted from peripheral blood cells and genotypes were determined using the polymerase chain reaction-restriction fragment length polymorphism. Polymorphism p53 Arg72Pro was not associated with either gastric or colorectal carcinoma, while XRCC1 Arg399Gln was not associated with the increased risk of colorectal cancer. However, XRCC1 homozygous Gln allele at codon 399 was associated with 2.54 times higher risk of gastric cancer.Rak želuca najčešći je oblik karcinoma probavnoga sustava, a ukupno mu je preživljenje i dalje 15 % do 20 %, budući da se većinom dijagnosticira u poodmakloj fazi razvoja. S druge pak strane, premda rak debeloga crijeva ima prilično dobru prognozu, smrtnost je i dalje 50 %. Vjeruje se da je nastanak karcinoma povezan s reaktivnim radikalima koji uzrokuju stvaranje DNA-adukata, onemogućavaju popravak DNA te slabe supresiju tumora. Stoga bi bilo korisno razumjeti ulogu polimorfi zama gena za enzim XRCC1 koji sudjeluje u popravku isjecanjem nukleotida i tumor-supresorskoga gena p53 u nastanku raka želuca i debeloga crijeva. Naše je ispitivanje obuhvatilo 94 bolesnika s rakom želuca, 96 bolesnika s rakom debeloga crijeva te 108 kontrolnhih ispitanika (koji nisu oboljeli od bilo kojeg oblika raka) s ciljem da se utvrdi povezanost između polimorfi zama XRCC1 Arg399Gln i p53 Arg72Pro i sklonosti nastanku raka. DNA je dobiven iz stanica periferne krvi, a genotip utvrđen s pomoću metode lančane reakcije polimerazom - polimorfi zma restrikcijskih fragmenata na osnovi dužine (PCRRLFP). Polimorfi zam p53 Arg72Pro nije se pokazao povezanim s povećanim rizikom od raka želuca ili debeloga crijeva niti je XRCC1 Arg399Gln bio povezan s povećanim rizikom od raka debeloga crijeva, ali je zato rizik od raka želuca u homozigotnih nositelja ovoga polimorfi zma bio 2,54 puta veći

    Quantum interference and manipulation of entanglement in silicon wire waveguide quantum circuits

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    Integrated quantum photonic waveguide circuits are a promising approach to realizing future photonic quantum technologies. Here, we present an integrated photonic quantum technology platform utilising the silicon-on-insulator material system, where quantum interference and the manipulation of quantum states of light are demonstrated in components orders of magnitude smaller than in previous implementations. Two-photon quantum interference is presented in a multi-mode interference coupler, and manipulation of entanglement is demonstrated in a Mach-Zehnder interferometer, opening the way to an all-silicon photonic quantum technology platform.Comment: 7 page

    A bi-articular model for scapular-humeral rhythm reconstruction through data from wearable sensors

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    Patient-specific performance assessment of arm movements in daily life activities is fundamental for neurological rehabilitation therapy. In most applications, the shoulder movement is simplified through a socket-ball joint, neglecting the movement of the scapular-thoracic complex. This may lead to significant errors. We propose an innovative bi-articular model of the human shoulder for estimating the position of the hand in relation to the sternum. The model takes into account both the scapular-toracic and gleno-humeral movements and their ratio governed by the scapular-humeral rhythm, fusing the information of inertial and textile-based strain sensors

    Pyrokinin β-Neuropeptide Affects Necrophoretic Behavior in Fire Ants (S. invicta), and Expression of β-NP in a Mycoinsecticide Increases Its Virulence

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    Fire ants are one of the world's most damaging invasive pests, with few means for their effective control. Although ecologically friendly alternatives to chemical pesticides such as the insecticidal fungus Beauveria bassiana have been suggested for the control of fire ant populations, their use has been limited due to the low virulence of the fungus and the length of time it takes to kill its target. We present a means of increasing the virulence of the fungal agent by expressing a fire ant neuropeptide. Expression of the fire ant (Solenopsis invicta) pyrokinin β -neuropeptide (β-NP) by B. bassiana increased fungal virulence six-fold towards fire ants, decreased the LT50, but did not affect virulence towards the lepidopteran, Galleria mellonella. Intriguingly, ants killed by the β-NP expressing fungus were disrupted in the removal of dead colony members, i.e. necrophoretic behavior. Furthermore, synthetic C-terminal amidated β-NP but not the non-amidated peptide had a dramatic effect on necrophoretic behavior. These data link chemical sensing of a specific peptide to a complex social behavior. Our results also confirm a new approach to insect control in which expression of host molecules in an insect pathogen can by exploited for target specific augmentation of virulence. The minimization of the development of potential insect resistance by our approach is discussed

    Controlled Release from Cleavable Polymerized Liposomes upon Redox and pH Stimulation

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    A gallate derivative with three propargyl groups was coupled to palmitoyl oleoyl phosphoethanolamine (POPE). The resulting anionic lipid was formulated with common lipids such as palmitoyl oleoyl phosphatidyl choline (POPC) to form large unilamellar vesicles (LUVs). Polymerization of the LUVs was accomplished by the Cu(I)-catalyzed click reaction between the propargyl groups and the azide groups in the cross-linker. When the cross-linker contained a disulfide or ketal group, the resulting polymerized liposomes depolymerized and released entrapped contents upon the addition of a reducing thiol or under weakly acidic conditions. The click reaction allowed simultaneous multivalent surface functionalization during cross-linking, making these cleavable polymerized liposomes (CPLs) potentially very useful in the delivery and controlled release of pharmaceutical agents

    Atribuciones causales y nivel educativo familiar en la comprensión del desempeño escolar en alumnos portugueses

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    Este artigo analisa o contributo específico do nível educativo familiar e das atribuições causais para o bom e fraco rendimento escolar dos alunos na explicação do seu desempenho nas disciplinas de Língua Portuguesa e de Matemática numa amostra de 2.082 alunos do ensino público de 11 escolas de Portugal, incluindo as Regiões Autónomas dos Açores e da Madeira. As atribuições causais foram avaliadas por meio do Questionário das Atribuições Causais para os Resultados Escolares (QARE). O nível educativo familiar foi estimado levando em conta o nível escolar do progenitor com maior habilitação escolar. As classificações obtidas pelos alunos nas disciplinas de língua portuguesa e matemática foram também examinadas. Os resultados apontam para correlações estatisticamente significativas, destacando as atribuições na capacidade para a explicação do rendimento escolar, situação que contrasta com a atribuição dos níveis de rendimento a variáveis externas ao aluno. A análise de regressão permite associar 34,5% da variância no rendimento conjunto em Língua Portuguesa e em Matemática no ensino básico, assim como 21,3% no ensino secundário, às dimensões atribucionais e ao nível educativo familiar. Implicações educacionais são derivadas a partir dos achados.This paper analyzes the contribution of both family educational level and causal attributions in explaining students´ academic performance in Mathematics and Portuguese Language in a sample of 2.082 public school students from mainland Portugal and the Azores and Madeira regions. Causal attributions were assessed by the Causal Attributions Questionnaire for School Results (QARE). The family educational level was estimated taking into account the educational level of the parent with higher academic degree. The academic grades obtained by students in mathematics and portuguese language were also considered. The results show statistically significant correlations between variables. Internal causal attributions such as capacity and study methods were predominant to explain school performance in the sample and stood out in contrast to external attributions explanations. Regression analyses revealed that 34.5% of the variance in the combined achievement on Portuguese Language and Mathematics in primary education and 21.3% in secondary education could be explained by both the attributional dimensions and family education level. Some educational implications are present taking these data.Este artículo analiza la contribución específica del nivel educativo familiar y de las atribuciones causales para el buen y el flaco rendimiento escolar de los alumnos en la explicación de su desempeño en las disciplinas de Lengua Portuguesa y Matemáticas en una muestra de 2.082 alumnos de enseñanza pública de 11 escuelas de Portugal, incluyendo las Regiones Autónomas de Açores y Madeira. Las atribuciones causales fueron evaluadas por medio del “Questionário das Atribuições Causais para os Resultados Escolares” (QARE). El nivel educativo familiar fue estimado teniendo en cuenta el nivel escolar del progenitor con mayor habilitación escolar. Las clasificaciones obtenidas por los alumnos en las disciplinas de lengua portuguesa y matemáticas fueron también examinadas. Los resultados señalaron correlaciones estadísticamente significativas, destacando las atribuciones en la capacidad para la explicación del rendimiento escolar, situación que contrasta con la atribución de los niveles de rendimiento a variables externas al alumno. El análisis de regresión permite asociar 34.5% de la variancia en el rendimiento conjunto de la Lengua Portuguesa y las Matemáticas en la enseñanza básica, así como 21.3% en la enseñanza secundaria, a las dimensiones de atribución y al nivel educativo familiar. Implicaciones educacionales son derivadas a partir de los hallazgos.Editora Universitária São Francisc

    MicroRNA-34a Inhibits the Proliferation and Metastasis of Osteosarcoma Cells Both In Vitro and In Vivo

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    BACKGROUND: MicroRNAs (miRNAs) are a class of endogenously expressed, small noncoding RNAs, which suppress its target mRNAs at the post-transcriptional level. Studies have demonstrated that miR-34a, which is a direct target of the p53 tumor suppressor gene, functions as a tumor suppressor and is associated with the tumor growth and metastasis of various human malignances. However, the role of miR-34a in osteosarcoma has not been totally elucidated. In the present study, the effects of miR-34a on osteosarcoma and the possible mechanism by which miR-34a affected the tumor growth and metastasis of osteosarcoma were investigated. METHODOLOGY/PRINCIPAL FINDING: Over-expression of miR-34a partially inhibited proliferation, migration and invasion of osteosarcoma cells in vitro, as well as the tumor growth and pulmonary metastasis of osteosarcoma cells in vivo. c-Met is a target of miR-34a, and regulates the migration and invasion of osteosarcoma cells. Osteosarcoma cells over-expressing miR-34a exhibited a significant decrease in the expression levels of c-Met mRNA and protein simultaneously. Finally, the results from bioinformatics analysis demonstrated that there were multiple putative targets of miR-34a that may be associated with the proliferation and metastasis of osteosarcoma, including factors in Wnt and Notch signaling pathways. CONCLUSION/SIGNIFICANCE: The results presented in this study demonstrated that over-expression of miR-34a could inhibit the tumor growth and metastasis of osteosarcoma probably through down regulating c-Met. And there are other putative miR-34a target genes beside c-Met which could potentially be key players in the development of osteosarcoma. Since pulmonary metastases are responsible for mortality of patient carrying osteosarcoma, miR-34a may prove to be a promising gene therapeutic agent. It will be interesting to further investigate the mechanism by which miR-34a functions as a tumor suppressor gene in osteosarcoma
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