959 resultados para C-erbb-2 Expression


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Objective. Helicobacter pylori infection is related to gastric cancer development, and chronic inflammation is presumed to be the main cause. The aim of the present study was to evaluate the influence of H. pylori cagA, vacA, iceA, and babA genotypes on COX-2, IL-1, and IL-8 expression. Material and methods. of the 217 patients included in the study, 26 were uninfected, 127 had chronic gastritis and were H. pylori-positive, and 64 had gastric cancer. Bacterial genotypes were evaluated by polymerase chain reaction (PCR), and the expression values were determined by quantitative real-time PCR and immunohistochemistry. Results. An association was found between the infection with cagA, vacA s1m1 strains and gastric cancer development. Regarding the 3' region of the cagA gene, we also found an association between the infection with cagA EPIYA-ABCCC strains and clinical outcome. Higher levels of IL-8, IL-1, and COX-2 were detected in gastric mucosa from infected patients with chronic gastritis, and they were also associated with the infection by cagA, vacA s1m1 strains. The IL-8 and IL-1 levels decrease significantly from chronic gastritis to gastric cancer, while the relative expression remained unaltered when COX-2 expression was analyzed among patients with gastritis and cancer. Conclusions. Since inflammatory response to H. pylori infection plays an important role in cellular proliferation and gastric mucosal damage, the up-regulation of IL-1, IL-8, and COX-2 in patients with chronic gastritis has an important clinical implication in gastric carcinogenesis.

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We aimed to evaluate the frequency of Kaposi sarcoma (KS)-associated herpesvirus (KSHV) infection in KS lesions in patients from Brazil. In addition, expression of human bcl-2, cleaved caspase-3, and KSHV latency-associated nuclear antigen (LANA)-1 in tumors was evaluated using inummohistochemical analysis. We studied 64 KS cases, classified as follows: classical, 20 (31 %); iatrogenic, 2 (3 %); AIDS-associated, 25 (39%); and not otherwise specified (lack of information about HIV status), 17 (27%). KSHV was detected by polymerase chain reaction (PCR) in 61 cases (95%); 40 cases (63%) were KSHV+ by PCR and immunohistochemical analysis for LANA-L Immunoexpression of bcl-2 was detected in 47 cases (73%). Only a few cells in 15 cases (23%) of KS had demonstrable immunostaining for cleaved caspase-3. These results further support the association of KSHV with all KS forms. Cleaved caspase-3 in KS tumors was infrequent, which may reflect the inhibition of apoptosis owing to bcl-2 overexpression observed in the majority of KS tumors.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Die Produktion von Hyperkernen wurde in peripheren Schwerionenreaktionen untersucht, bei denen eine Kohlenstofffolie mit $^6$Li Projektilen mit einer Strahlenergie von $2 A$~GeV bestrahlt wurde. Es konnten klare Signale f{"{u}}r $Lambda$, $^3_{Lambda}$H, $^4_{Lambda}$H in deren jeweiligen invarianten Massenverteilungen aus Mesonenzerfall beobachtet werden.rnrnIn dieser Arbeit wird eine unabh{"{a}}ngige Datenauswertung vorgelegt, die eine Verifizierung fr"{u}herer Ergebnisse der HypHI Kollaboration zum Ziel hatte. Zu diesem Zweck wurde eine neue Track-Rekonstruktion, basierend auf einem Kalman-Filter-Ansatz, und zwei unterschiedliche Algorithmen zur Rekonstruktion sekund"{a}rer Vertices entwickelt.rn%-Rekonstruktionsalgorithmen .rnrnDie invarianten Massen des $Lambda$-Hyperon und der $^3_{Lambda}$H- und $^4_{Lambda}$H-Hyperkerne wurden mit $1109.6 pm 0.4$, $2981.0 pm 0.3$ und $3898.1 pm 0.7$~MeV$/c^2$ und statistischen Signifikanzen von $9.8sigma$, $12.8sigma$ beziehungsweise $7.3sigma$ bestimmt. Die in dieser Arbeit erhaltenen Ergebnisse stimmen mit der fr{"{u}}heren Auswertung {"{u}}berein.rnrnDas Ausbeutenverh{"{a}}ltnis der beiden Hyperkerne wurde als $N(^3_{Lambda}$H)/$N(^4_{Lambda}$H)$ sim 3$ bestimmt. Das deutet darauf hin, dass der Produktionsmechanismus f{"{u}}r Hyperkerne in Schwerionen-induzierten Reaktionen im Projektil-Rapidit{"{a}}tsbereich nicht allein durch einen Koaleszenzmechanismus beschrieben werden kann, sondern dass auch sekund{"{a}}re Pion-/Kaon-induzierte Reaktionen und Fermi-Aufbruch involviert sind.rn

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Expression of N-myc downregulated gene 1 (NDRG1) is associated with growth arrest and differentiation of tumor cells. In hematopoietic cells, NDRG1 was identified in a screen for differentiation-related genes in human myelomonocytic leukemic U937 cells. In the present study, we found significantly higher NDRG1 mRNA levels in granulocytes of healthy donors than in primary acute myeloid leukemia (AML) cells. Another NDRG family member, NDRG2, was significantly higher expressed in normal macrophages compared to primary AML cells. Moreover, NDRG1 mRNA levels increased in two acute promyelocytic leukemia (APL) patients as well as in NB4 and HT93 APL cells upon all-trans retinoic acid (ATRA) therapy. In line with these observations, silencing of NDRG1 diminished neutrophil differentiation of leukemic cell lines. In conclusion, we found an association of low NDRG1 levels with an immature cell phenotype and provide evidence that NDRG1 is functionally involved in neutrophil maturation.

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Filaggrin loss-of-function mutations resulting in C-terminal protein truncations are strong predisposing factors in human atopic dermatitis (AD). To assess the possibility of similar truncations in canine AD, an exclusion strategy was designed on 16 control and 18 AD dogs of various breeds. Comparative immunofluorescence microscopy was performed with an antibody raised against the canine filaggrin C-terminus and a commercial N-terminal antibody. Concurrent with human AD-like features such as generalized NFKB activation and hyperproliferation, four distinctive filaggrin expression patterns were identified in non-lesional skin. It was found that 10/18 AD dogs exhibited an identical pattern for both antibodies with comparable (category I, 3/18) or reduced (category II, 7/18) expression to that of controls. In contrast, 4/18 dogs displayed aberrant large vesicles revealed by the C-terminal but not the N-terminal antibody (category III), while 4/18 showed a control-like N-terminal expression but lacked the C-terminal protein (category IV). The missing C-terminal filaggrin in category IV strongly points towards loss-of function mutations in 4/18 (22%) of all AD dogs analysed.

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Understanding the mechanisms of sphingosine 1-phosphate (S1P)-induced cyclooxygenase (COX)-2 expression and prostaglandin E2 (PGE2) formation in renal mesangial cells may provide potential therapeutic targets to treat inflammatory glomerular diseases. Thus, we evaluated the S1P-dependent signaling mechanisms which are responsible for enhanced COX-2 expression and PGE2 formation in rat mesangial cells under basal conditions. Furthermore, we investigated whether these mechanisms are operative in the presence of angiotensin II (Ang II) and of the pro-inflammatory cytokine interleukin-1β (IL-1β). Treatment of rat and human mesangial cells with S1P led to concentration-dependent enhanced expression of COX-2. Pharmacological and molecular biology approaches revealed that the S1P-dependent increase of COX-2 mRNA and protein expression was mediated via activation of S1P receptor 2 (S1P2). Further, inhibition of Gi and p42/p44 MAPK signaling, both downstream of S1P2, abolished the S1P-induced COX-2 expression. In addition, S1P/S1P2-dependent upregulation of COX-2 led to significantly elevated PGE2 levels, which were further potentiated in the presence of Ang II and IL-1β. A functional consequence downstream of S1P/S1P2 signaling is mesangial cell migration that is stimulated by S1P. Interestingly, inhibition of COX-2 by celecoxib and SC-236 completely abolished the migratory response. Overall, our results demonstrate that extracellular S1P induces COX-2 expression via activation of S1P2 and subsequent Gi and p42/p44 MAPK-dependent signaling in renal mesangial cells leading to enhanced PGE2 formation and cell migration that essentially requires COX-2. Thus, targeting S1P/S1P2 signaling pathways might be a novel strategy to treat renal inflammatory diseases.

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We describe the synthesis of (5 S )-5- C -butylthymidine ( 5a ), of the (5 S )-5- C -butyl- and the (5 S )-5- C -isopentyl derivatives 16a and 16b of 2-deoxy-5-methylcytidine, as well as of the corresponding cyanoethyl phosphoramidites 9a , b and 14a , b , respectively. Starting from thymidin-5-al 1 , the alkyl chain at C(5) is introduced via Wittig chemistry to selectively yield the ( Z )-olefin derivatives 3a and 3b ( Scheme 2 ). The secondary OH function at C(5) is then introduced by epoxidation followed by regioselective reduction of the epoxy derivatives 4a and 4b with diisobutylaluminium hydride. In the latter step, a kinetic resolution of the diastereoisomer mixture 4a and 4b occurs, yielding the alkylated nucleoside 2a and 2b , respectively, with (5 S )-configuration in high diastereoisomer purity (de=94%). The corresponding 2-deoxy-5-methylcytidine derivatives are obtained from the protected 5-alkylated thymidine derivatives 7a and 7b via known base interconversion processes in excellent yields ( Scheme 3 ). Application of the same strategy to the purine nucleoside 2-deoxyadenine to obtain 5- C -butyl-2-deoxyadenosine 25 proved to be difficult due to the sensitivity of the purine base to hydride-based reducing agents ( Scheme 4 ).

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Objectives. Triple Negative Breast Cancer (TNBC) lack expression of estrogen receptors (ER), progesterone receptors (PR), and absence of Her2 gene amplification. Current literature has identified TNBC and over-expression of cyclo-oxygenase-2 (COX-2) protein in primary breast cancer to be independent markers of poor prognosis in terms of overall and distant disease free survival. The purpose of this study was to compare COX-2 over-expression in TNBC patients to those patients who expressed one or more of the three tumor markers (i.e. ER, and/or PR, and/or Her2).^ Methods. Using a secondary data analysis, a cross-sectional design was implemented to examine the association of interest. Data collected from two ongoing protocols titled "LAB04-0657: a model for COX-2 mediated bone metastasis (Specific aim 3)" and "LAB04-0698: correlation of circulating tumor cells and COX-2 expression in primary breast cancer metastasis" was used for analysis. A sample of 125 female patients was analyzed using Chi-square tests and logistic regression models. ^ Results. COX-2 over-expression was present in 33% (41/125) and 28% (35/124) patients were identified as having TNBC. TNBC status was associated with elevated COX-2 expression (OR= 3.34; 95% CI= 1.40–8.22) and high tumor grade (OR= 4.09; 95% CI= 1.58–10.82). In a multivariable analysis, TNBC status was an important predictor of COX-2 expression after adjusting for age, menopausal status, BMI, and lymph node status (OR= 3.31; 95% CI: 1.26–8.67; p=0.01).^ Conclusion. TNBC is associated with COX-2 expression—a known marker of poor prognosis in patients with operable breast cancer. Replication of these results in a study with a larger sample size, or a future randomized clinical trial demonstrating an improved prognosis with COX-2 suppression in these patients would support this hypothesis.^