253 research outputs found
Clinical significance of T-bet, GATA-3, and Bcl-6 transcription factor expression in bladder carcinoma
International audienceBackground: The aim of this study was to investigate the clinical significance of three immune cell-related transcription factors, T-bet, GATA-3 and Bcl-6 in bladder cancer in Tunisian patients.Methods: Expression of T-bet, GATA-3 and Bcl-6 genes was assessed using RT-qPCR in 65 bladder cancers from patients: 32 being diagnosed as low-and medium-grade, 31 as high-grade, 25 as muscle invasive stage and 39 as non-muscle invasive stage. Gene expression was statistically correlated according to the grade, the stage, tobacco consumption, the BCG response and disease severity.Results: T-bet levels in patients with high-grade bladder cancer were significantly elevated compared to patients with low-or medium-grade bladder cancer (p = 0.005). In invasive carcinoma (T2-T4), the T-bet levels were significantly higher than in superficial non-invasive bladder tumors (Tis, Ta, and T1) (p = 0.02). However, T-bet is predictive of the response to BCG. Its expression is high in good responders to BCG (p = 0.02). In contrast, the expression of GATA-3 and Bcl-6 in non-invasive carcinoma (p = 0.008 and p = 0.0003) and in patients with low-and medium-grade cancers (p = 0.001 and p < 0.0001) is significantly higher than in invasive bladder tumors and in patients with high-grade bladder carcinoma, respectively. In addition, heavy smokers, whose tumors express low levels of GATA-3 and Bcl-6, are poor responders to BCG (p = 0.01 and p = 0.03). Finally, better patient survival correlated with GATA-3 (p = 0.04) and Bcl-6 (p = 0.04) but not T-bet expression.Conclusions: Our results suggest that T-bet expression in bladder tumors could be a positive prognostic indicator of BCG therapy, even if high levels are found in high-grade and stage of the disease. However, GATA-3 and Bcl-6 expression could be considered as predictive factors for good patient survival
Etude de films ultraminces de polystyrène par réflectivité des rayons X et ellipsométrie en fonction de leur exposition à du CO2
The aim of this work is to study in-situ and ex-situ interaction of carbon dioxide (CO2) with thin films of polystyrene and surfaces by two main techniques: the X-ray reflectivity (XRR) and ellipsometry.In this thesis, we address the study of the physical properties of polystyrene films (PS) in the confined state (thin films) and their evolution when exposed to CO2 pressure. We demonstrate by XRR and ellipsometry in the same films that the density and the refractive index increase when the film thickness decreases. We confirm the decrease of Tg for PS films of thickness less than 70 nm according to the empirical law of Keddie [1]. Both results could mean that ultrathin films have a certain organization of channels.We then discuss the behavior of PS ultra thin films exposed to CO2 as a function of CO2 pressure by XRR made at synchrotron radiation (ESRF ID10B line). We monitor in situ the swelling and deswelling of the 7 nm thin film thickness upon pressurization and depressurization of CO2. By calculating the evolution of the electron density in the film, we highlight the existence of a glass transition pressure Pg and a residual swelling due to the presence of CO2 molecules trapped inside the film [2].We propose then an ex-situ XRR study of swelling and kinetic of deswelling for PS swollen films. We observe that the thin films have a higher swelling and deswelling capacity compare to the thicker films. We note that this phenomenon is highly dependent to the depressurization rate. Indeed, we find that the rapid depressurization greatly enhances not only the swelling of the film, but also its deswelling over time. We then highlight that the rate of depressurization clearly governs the final state of swolen films, to say the metastable state or glassy state.Finally, we study the effect of film swelling by CO2 on the evolution of the glass transition temperature. This study is carried out mainly by ellipsometry. We show that these films which showed only a single Tg value before exposure, after exposure has three values of Tg completely independent of film thickness. By following the thickness evolution of these swollen films as a function of temperature, we offer answers that can explain the different Tg values observed. In addition, we highlight the existence of CO2 stored in these films. After annealing above 150 ° C, the films show the same behavior as before exposure to CO2 which is far from the equilibrium state of the bulk polymer. We confirm therefore the existence of strong restoring forces in ultrathin films that bring them back to their initial states of non-equilibrium. This result presents similarities to that concerning the evolution of the Tg due to confinement in ultrathin films before exposure.L’objectif principal de ce travail est d’étudier in-situ et ex-situ l’interaction du dioxyde de carbone (CO2) avec les films minces de polystyrène et les surfaces par deux techniques principales : la réflectivité des rayons X (RRX) et l’ellipsométrie.Dans cette thèse, nous abordons l’étude des propriétés physiques de films de polystyrène (PS) à l’état confiné (films minces) et leur évolution lors de leur exposition à du CO2 sous pression. Nous démontrons par RRX et par ellipsométrie sur les mêmes films que la densité et l’indice de réfraction augmentent quand l’épaisseur du film diminue. Nous confirmons la diminution de Tg pour des films de PS d’épaisseur inférieure à 70 nm selon la loi empirique de Keddie [1]. Ces deux résultats pourraient signifier que les films ultraminces présentent une certaine organisation des chaines.Nous abordons ensuite le comportement des films ultra minces de PS exposés à du CO2 en fonction de la pression de CO2 par réflectivité de rayons X (RRX) faite au rayonnement synchrotron (ESRF ligne ID10B). Nous suivons in-situ le gonflement et le dégonflement du film mince d’épaisseur 7 nm lors de la pressurisation et la dépressurisation du CO2. Par calcul de l’évolution de la densité électronique dans le film, nous mettons en évidence l’existence d’une pression de transition vitreuse Pg et d’un gonflement rémanent lié à la présence de molécules de CO2 piégées dans le film [2].Nous proposons par la suite une étude ex-situ par RRX du gonflement et de l’évolution au cours du temps des films de PS gonflés. Nous observons que les films minces présentent une plus grande capacité de gonflement et dégonflement au cours du temps par opposition aux films plus épais. Nous constatons que ce phénomène est fortement dépendant du taux de dépressurisation. En effet, nous constatons que la dépressurisation rapide renforce considérablement, non seulement le gonflement du film, mais aussi son dégonflement au cours du temps. Nous mettons alors en évidence que le taux de dépressurisation régit clairement l'état final des films gonflés, à savoir l’état métastable ou l’état vitreux.Finalement, nous étudions l’influence du gonflement du film par le CO2 sur l’évolution de la température de transition vitreuse. Cette étude est effectuée principalement par ellipsométrie. Nous montrons que ces films qui ne présentaient qu’une valeur unique de Tg avant exposition, présentent après exposition trois valeurs de Tg. En suivant l’évolution de l’épaisseur de ces films gonflés en fonction de la température, nous proposons des réponses qui peuvent expliquer les différentes Tg observées. En outre, nous mettons en évidence l’existence du CO2 stocké dans les films. Après un recuit au dessus de 150°C, les films reprennent le même comportement qu’avant exposition au CO2 qui est loin d’être l’état d’équilibre du polymère massique. Nous confirmons par ce fait l’existence de fortes forces de rappel dans les films ultraminces qui les ramènent vers leurs états initiaux de non équilibre. Ce résultat est à rapprocher de celui concernant l’évolution de la Tg due au confinement dans les films ultraminces avant exposition
Imaging of melanoma: usefulness of ultrasonography before and after contrast injection for diagnosis and early evaluation of treatment
High-frequency ultrasound (8–14 MHz) is routinely used to display cutaneous melanomas. Maximum thickness measurement (Breslow index) has been shown to be well correlated to histologic findings for lesions of more than 0.75 mm. Some morphological criteria (strong delineation, hypoechoic texture, homogeneity) have been reported to help differentiate between malignant and benign pigmented blue lesions, but remain insufficient. Vascular ultrasound analysis using Doppler mode provides additional information and showed good specificity for malignancy (90%–100%), but variable sensitivity (34%–100%). Recent advances in ultrasound imaging allow functional evaluation. Likewise, dynamic contrast-enhanced ultrasound using contrast medium injection and specific perfusion and quantification software showed promising results in clinical and preclinical trials for early prediction of tumor response to target treatments
Convolutional neural network-based finger vein recognition using near infrared images
Convolutional Neural Network (CNN) is opening
new horizons in biometrics-based authentication field and
finger vein recognition is the prominent one which can provide
the best possible security system depending on this
aforementioned technology. In this paper, we used 5
convolutional layers and 4 fully-connected layers where our
developed network has shown the capability to produce the
result with almost 100% accuracy rate which became possible
due to the fact that deep learning, an end-to-end system is used
which performs better in a lot of aspects in comparison to
conventional techniques.Convolutional Neural Network (CNN) is opening
new horizons in biometrics-based authentication field and
finger vein recognition is the prominent one which can provide
the best possible security system depending on this
aforementioned technology. In this paper, we used 5
convolutional layers and 4 fully-connected layers where our
developed network has shown the capability to produce the
result with almost 100% accuracy rate which became possible
due to the fact that deep learning, an end-to-end system is used
which performs better in a lot of aspects in comparison to
conventional techniques
Biocatalysis of Rutin Hexadecanedioate Derivatives: Effect of Operating Conditions on Acylation Performance and Selectivity
Rutin was enzymatically acylated with hexadecanedioic acid, in tert‐amyl alcohol, by an immobilized lipase from Candida antartica “Novozym 435”. The effect of different techniques of water removal, temperature, concentration of rutin and diacid/rutin molar ratio was investigated. The obtained results indicated that drying the media by adding the molecular sieves in the outer loop of the reactor was the most efficient method leading to water content lower than 200 ppm. The highest performances (conversion yield and initial rate) were reached at 90°C, 131 mM of rutin, and 118 mM of acid. Depending on the water content and the diacid/rutin molar ratio, only rutin 4‴‐hexadecanedioate or both rutin 4‴‐hexadecanedioate and dirutin 4‴, 4‴‐hexadecanedioate were synthesized
Thermal stability of polymethacrylic based ELIUM® resin: Effect of comonomers, antioxidants and aluminum trihydrate filler
This paper presents the study of the thermal degradation of methyl methacrylate resin based materials known as ELIUM® resin. Samples under investigation were made from MMA based resin (ELIUM® V1), ELIUM® V1 with a dimethacrylate comonomer (ELIUM® V2), and ELIUM® V2 with a stabilizer package (ELIUM® V3). They were used for trying to discuss the degradation mechanisms. Blocks differing by their thickness made from ELIUM® formulation filled with aluminum TriHydrate used as flame retardant were also investigated in order to better match some industrial materials. Degradation was observed to be mainly driven by unzipping, consistent with the methacrylic nature of ELIUM® resin. Occurrence of oxidation is also discussed depending on materials formulation and temperature. A blend of antioxidants was inefficient for limiting mass loss. At 200 °C, both ATH and ELIUM® degrade, which contributes to overall mass loss. At temperatures below 180 °C, ATH does not seem to induce new degradation mechanisms but would increase oxygen diffusivity. Finally, a first simple kinetic model is proposed to predict mass loss in thick composite blocks aged under air
Cytokeratin 18 expression pattern correlates with renal cell carcinoma progression: Relationship with Snail
Renal cell carcinoma (RCC) is the most common type of kidney cancer and recent developments in the molecular biology of RCC have identified multiple pathways associated with the development of this cancer. This study aimed at analyzing the expression pattern of cytokeratin 18 (CK18) in RCC patients and its prognostic relevance. We quantified CK18 mRNA expression and protein using real-time reverse transcription quantitative polymerase chain reaction (RT-QPCR) and immunohistochemistry, respectively, in paired tumor and non-tumor samples from 42 patients. Our data indicate that CK18 mRNA and proteins levels increased with advanced stage and grade of the disease. Using primary (RCC5) and metastatic renal cell carcinoma (RCC5 met) cell lines, we demonstrated that CK18 expression was 5-fold higher in the metastatic as compared to the primary RCC cell line and correlated with a migratory phenotype characterized by a distinct elongated morphology as revealed by Phalloidin staining. In addition, RCC5 met cells displayed an increased capacity to attach to fibronectin and collagen which was lost following CK18 knock-down. Our data also indicate that the expression of CK18 was associated with increased Snail expression which correlated positively with advanced disease in RCC patients. The present findings suggest that CK18 may play an important role in the progression of RCC and it may be used as a new predictor for RCC
Enzymatic Polymerization of Rutin and Esculin and Evaluation of the Antioxidant Capacity of Polyrutin and Polyesculin
Comparison of the Performance of the Laccase Bioconversion of Sodium Lignosulfonates in Batch, Continuous and Fed Batch Reactors
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