168 resultados para career progression


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BACKGROUND: The aim of this study was to evaluate the inhibitory growth effects of different potential chemopreventive agents in vitro and to determine their influence on PSA mRNA and protein expression with an established screening platform. METHODS: LNCaP and C4-2 cells were incubated with genistein, seleno-L-methionine, lycopene, DL-alpha-tocopherol, and trans-beta-carotene at three different concentrations and cell growth was determined by the MTT assay. PSA mRNA expression was assessed by quantitative real-time RT-PCR and secreted PSA protein levels were quantified by the microparticle enzyme immunoassay. RESULTS: Genistein, seleno-l-methionine and lycopene inhibited LNCaP cell growth, and the proliferation of C4-2 cells was suppressed by seleno-L-methionine and lycopene. PSA mRNA expression was downregulated by genistein in LNCaP but not C4-2 cells. No other compound tested altered PSA mRNA expression. PSA protein expression was downregulated by genistein, seleno-L-methionine, DL-alpha-tocopherol in LNCaP cells. In C4-2 cells only genistein significantly reduced the secretion of PSA protein. CONCLUSIONS: In the LNCaP progression model PSA expression depends on the compound, its concentration and on the hormonal dependence of the cell line used and does not necessarily reflect cell growth or death. Before potential substances are evaluated in clinical trials using PSA as a surrogate end point marker, their effect on PSA mRNA and protein expression has to be considered to correctly assess treatment response by PSA.

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BACKGROUND ; AIMS: Integrin alphavbeta6 is highly expressed on certain activated epithelia, where it mediates attachment to fibronectin and serves as coreceptor for the activation of latent transforming growth factor (TGF)-beta1. Because its role in liver fibrosis is unknown, we studied alphavbeta6 function in vitro and explored the antifibrotic potential of the specific alphavbeta6 antagonist EMD527040. METHODS: Experimental liver fibrosis was studied in rats after bile duct ligation (BDL) and in Mdr2(abcb4)(-/-) mice. Different doses of EMD527040 were given to rats from week 2 to 6 after BDL and to Mdr2(-/-) mice from week 4 to 8. Liver collagen was quantified, and expression of alphavbeta6 and fibrosis-related transcripts was determined by quantitative reverse-transcription polymerase chain reaction. alphavbeta6-expressing cells, bile duct proliferation, and apoptosis were assessed histologically. The effect of EMD527040 on cholangiocyte adhesion, proliferation, apoptosis, and TGF-beta1 activation was studied in vitro. RESULTS: alphavbeta6 was highly expressed on proliferating bile duct epithelia in fibrosis, with 100-fold increased transcript levels in advanced fibrosis. EMD527040 attenuated bile ductular proliferation and peribiliary collagen deposition by 40%-50%, induced down-regulation of fibrogenic and up-regulation of fibrolytic genes, and improved liver architecture and function. In vitro alphavbeta6 inhibition reduced activated cholangiocyte proliferation, their adhesion to fibronectin, and endogenous activation of TGF-beta1 by 50% but did not affect bile duct apoptosis. CONCLUSIONS: Integrin alphavbeta6 is strongly up-regulated in proliferating bile duct epithelia and drives fibrogenesis via adhesion to fibronectin and auto/paracrine TGF-beta1 activation. Pharmacologic inhibition of alphavbeta6 potently inhibits the progression of primary and secondary biliary fibrosis.

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BACKGROUND/AIMS: The integrin alphavbeta6 promotes proliferation of specialized epithelia and acts as a receptor for the activation of latent TGFbeta1. We studied alphavbeta6 expression in experimental and human liver fibrosis and the potential of its pharmacological inhibition for treatment of hepatic fibrosis. METHODS: alphavbeta6 expression was studied by quantitative PCR and immunohistochemistry in rats with cirrhosis due to bile duct ligation (BDL), administration of thioacetamide (TAA), in Mdr2(Abcb4)(-/-) mice with spontaneous biliary fibrosis, and in livers of patients with chronic hepatitis C (n=79) and end-stage liver disease due to various etiologies (n=18). The effect of a selective alphavbeta6 inhibitor was evaluated in Mdr2(Abcb4)(-/-) mice with ongoing fibrogenesis. RESULTS: Integrin beta6 mRNA increased with fibrosis stage in hepatitis C and was upregulated between 25- and 100-fold in TAA- and BDL-induced cirrhosis, in Mdr2(Abcb4)(-/-) mice and in human end-stage liver disease. alphavbeta6 protein was absent in normal livers and expressed de novo on (activated) bile duct epithelia and transitional hepatocytes. A single dose of the alphavbeta6 inhibitor injected into Mdr2(Abcb4)(-/-) mice significantly induced profibrolytic matrix metalloproteinases (MMP)-8 and -9 after 3 h, with a corresponding increase in extracellular matrix-degrading activities. In parallel profibrogenic transcripts (procollagen alpha1(I), TGFbeta2, and MMP-2) showed a trend of downregulation. CONCLUSIONS: (1) Integrin alphavbeta6 is induced de novo in rodent and human liver fibrosis, where it is expressed on activated bile duct epithelia and (transitional) hepatocytes during fibrosis progression. (2) In vivo a single dose of a small molecule alphavbeta6 inhibitor induced antifibrogenic and profibrolytic genes and activities, suggesting alphavbeta6 is a unique target for treatment of liver fibrosis.

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BACKGROUND/AIMS: While several risk factors for the histological progression of chronic hepatitis C have been identified, the contribution of HCV genotypes to liver fibrosis evolution remains controversial. The aim of this study was to assess independent predictors for fibrosis progression. METHODS: We identified 1189 patients from the Swiss Hepatitis C Cohort database with at least one biopsy prior to antiviral treatment and assessable date of infection. Stage-constant fibrosis progression rate was assessed using the ratio of fibrosis Metavir score to duration of infection. Stage-specific fibrosis progression rates were obtained using a Markov model. Risk factors were assessed by univariate and multivariate regression models. RESULTS: Independent risk factors for accelerated stage-constant fibrosis progression (>0.083 fibrosis units/year) included male sex (OR=1.60, [95% CI 1.21-2.12], P<0.001), age at infection (OR=1.08, [1.06-1.09], P<0.001), histological activity (OR=2.03, [1.54-2.68], P<0.001) and genotype 3 (OR=1.89, [1.37-2.61], P<0.001). Slower progression rates were observed in patients infected by blood transfusion (P=0.02) and invasive procedures or needle stick (P=0.03), compared to those infected by intravenous drug use. Maximum likelihood estimates (95% CI) of stage-specific progression rates (fibrosis units/year) for genotype 3 versus the other genotypes were: F0-->F1: 0.126 (0.106-0.145) versus 0.091 (0.083-0.100), F1-->F2: 0.099 (0.080-0.117) versus 0.065 (0.058-0.073), F2-->F3: 0.077 (0.058-0.096) versus 0.068 (0.057-0.080) and F3-->F4: 0.171 (0.106-0.236) versus 0.112 (0.083-0.142, overall P<0.001). CONCLUSIONS: This study shows a significant association of genotype 3 with accelerated fibrosis using both stage-constant and stage-specific estimates of fibrosis progression rates. This observation may have important consequences for the management of patients infected with this genotype.

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BACKGROUND: Osteoporosis has been recognized as an important side effect of long-term and of pulsed steroid application after heart transplantation. METHODS: In June 1989 a prospective clinical trial was started to study bone demineralization by quantitative computed tomographic scan. All patients received vitamin D and calcium. In group I (n = 30) synthetic calcitonin (40 Medical Research Council Standard Units subcutaneously per day was administered in 14-day cycles, whereas group II patients (n = 31) received a placebo preparation. Repeat trabecular and cortical quantitative computed tomographic scans of the thoracic (T12) and lumbar spine (L1, L2, L3) were obtained within 48 weeks after heart transplantation. RESULTS: Expressed as the means of T12, L1, L2, and L3, trabecular bone density decreased significantly from 100+/-24 to 79+/-29 mg/mL within 3 weeks after heart transplantation, followed by a further reduction to 67+/-29 mg/mL after 3 months in the calcitonin group. The values for cortical bone density decreased significantly from 229+/-37 to 202+/-40 mg/mL (calcitonin) 3 weeks after heart transplantation. Comparable results were obtained in the placebo group. In both groups bone density remained stable thereafter. Intergroup differences were not of statistical significance. CONCLUSIONS: In heart transplant recipients progressive trabecular bone demineralization is limited to the first 3 postoperative months. Thereafter, bone density remained stable. A positive effect of synthetic calcitonin in addition to prophylactic calcium and vitamin D application could not be proved by repeat quantitative computed tomography.

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AIMS: To assess rates of periodontal disease progression in subjects with cleft lip, alveolus and palate (CLAP) over a 25-year period without regular maintenance care in a specialist setting and to compare those with those of subjects without alveolar clefts, i.e. cleft lip (CL) or cleft palate (CP). MATERIAL AND METHODS: Ten subjects with CLAP and 10 subjects with CL/CP were examined in 1979, 1987, 1993 and 2004. Probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP) and plaque control record (PCR) scores were recorded in all 20 subjects. RESULTS: High plaque and BoP scores were recorded at all examinations in both groups. Over 25 years, a statistically significant loss of mean full-mouth CAL of 1.52 +/- 0.12 mm (SD) and 1.66 +/- 0.15 mm occurred in the CLAP and CL/CP group respectively (p<0.05). A statistically significant increase (p<0.05) in mean full-mouth PPD of 0.35 +/- 0.12 mm was observed in the CL/CP group, whereas only a trend for a mean full-mouth increase in PPD of 0.09 +/- 0.11 mm was observed in the CLAP group. In subjects with CLAP, a statistically significant increase (p<0.05) in PPD of 0.92 +/- 1.13 mm at cleft sites was observed compared with that of 0.17 +/- 0.76 mm at control sites. With respect to CAL, the loss at the corresponding sites amounted to 2.71 +/- 1.46 and to 2.27 +/- 1.62 mm, respectively (p=0.36). CONCLUSIONS: When stringent and well-defined supportive periodontal therapy was not provided, subjects with orofacial clefts were at high risk for periodontal disease progression. Over 25 years, alveolar cleft sites tended to have more periodontal tissue destruction compared with control sites.

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Chronic myeloid leukemia (CML) is a malignant myeloproliferative disease with a characteristic chronic phase (cp) of several years before progression to blast crisis (bc). The immune system may contribute to disease control in CML. We analyzed leukemia-specific immune responses in cpCML and bcCML in a retroviral-induced murine CML model. In the presence of cpCML and bcCML expressing the glycoprotein of lymphocytic choriomeningitis virus as a model leukemia antigen, leukemia-specific cytotoxic T lymphocytes (CTLs) became exhausted. They maintained only limited cytotoxic activity, and did not produce interferon-gamma or tumor necrosis factor-alpha or expand after restimulation. CML-specific CTLs were characterized by high expression of programmed death 1 (PD-1), whereas CML cells expressed PD-ligand 1 (PD-L1). Blocking the PD-1/PD-L1 interaction by generating bcCML in PD-1-deficient mice or by repetitive administration of alphaPD-L1 antibody prolonged survival. In addition, we found that PD-1 is up-regulated on CD8(+) T cells from CML patients. Taken together, our results suggest that blocking the PD-1/PD-L1 interaction may restore the function of CML-specific CTLs and may represent a novel therapeutic approach for CML.

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Phosphatidylethanolamine (PE) and phosphatidylcholine (PC) are the two major constituents of eukaryotic cell membranes. In the protist Trypanosoma brucei, PE and PC are synthesized exclusively via the Kennedy pathway. To determine which organelles or processes are most sensitive to a disruption of normal phospholipid levels, the cellular consequences of a decrease in the levels of PE or PC, respectively, were studied following RNAi knock-down of four enzymes of the Kennedy pathway. RNAi against ethanolamine-phosphate cytidylyltransferase (ET) disrupted mitochondrial morphology and ultrastructure. Electron microscopy revealed alterations of inner mitochondrial membrane morphology, defined by a loss of disk-like cristae. Despite the structural changes in the mitochondrion, the cells maintained oxidative phosphorylation. Our results indicate that the inner membrane morphology of T. brucei procyclic forms is highly sensitive to a decrease of PE levels, as a change in the ultrastructure of the mitochondrion is the earliest phenotype observed after RNAi knock-down of ET. Interference with phospholipid synthesis also impaired normal cell-cycle progression. ET RNAi led to an accumulation of multinucleate cells. In contrast, RNAi against choline-/ethanolamine phosphotransferase, which affected PC as well as PE levels, caused a cell division phenotype characterized by non-division of the nucleus and production of zoids.

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BACKGROUND Trials assessing the benefit of immediate androgen-deprivation therapy (ADT) for treating prostate cancer (PCa) have often done so based on differences in detectable prostate-specific antigen (PSA) relapse or metastatic disease rates at a specific time after randomization. OBJECTIVE Based on the long-term results of European Organization for Research and Treatment of Cancer (EORTC) trial 30891, we questioned if differences in time to progression predict for survival differences. DESIGN, SETTING, AND PARTICIPANTS EORTC trial 30891 compared immediate ADT (n=492) with orchiectomy or luteinizing hormone-releasing hormone analog with deferred ADT (n=493) initiated upon symptomatic disease progression or life-threatening complications in randomly assigned T0-4 N0-2 M0 PCa patients. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Time to first objective progression (documented metastases, ureteric obstruction, not PSA rise) and time to objective castration-resistant progressive disease were compared as well as PCa mortality and overall survival. RESULTS AND LIMITATIONS After a median of 12.8 yr, 769 of the 985 patients had died (78%), 269 of PCa (27%). For patients receiving deferred ADT, the overall treatment time was 31% of that for patients on immediate ADT. Deferred ADT was significantly worse than immediate ADT for time to first objective disease progression (p<0.0001; 10-yr progression rates 42% vs 30%). However, time to objective castration-resistant disease after deferred ADT did not differ significantly (p=0.42) from that after immediate ADT. In addition, PCa mortality did not differ significantly, except in patients with aggressive PCa resulting in death within 3-5 yr after diagnosis. Deferred ADT was inferior to immediate ADT in terms of overall survival (hazard ratio: 1.21; 95% confidence interval, 1.05-1.39; p [noninferiority]=0.72, p [difference] = 0.0085). CONCLUSIONS This study shows that if hormonal manipulation is used at different times during the disease course, differences in time to first disease progression cannot predict differences in disease-specific survival. A deferred ADT policy may substantially reduce the time on treatment, but it is not suitable for patients with rapidly progressing disease.

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Back Cover Text This collection covers how success and well-being relate to each other in early career development in the domains of employment and education. It gives a conceptual overview of success and well-being as established in the psychological research tradition, complemented by educational and sociological approaches. The volume presents articles on success and well-being in applied contexts, such as well-being as an individual resource during school-to-work transition, or well-being and success at the workplace. Work psychologists, social psychologists, educational researchers, and sociologists will find this book valuable, as it provides unique insights into social and psychological processes afforded by the combination of disciplines, concepts, and a diversity of approaches. Table of Contents Acknowledgements 1. Introduction Robin Samuel, Manfred Max Bergman, Anita C. Keller and Norbert K. Semmer 2. The Influence of Career Success on Subjective Well-Being Andrea E. Abele-Brehm 3. Upper-Secondary Educational Trajectories and Young Men’s and Women’s Self-Esteem Development in Switzerland Sybille Bayard, Monika Staffelbach, Phillip Fischer and Marlies Buchmann. 4. Young People’s Progress after Dropout from Vocational Edu-cation and Training: Transitions and Occupational Integration at Stake. Longitudinal Qualitative Perspective Barbara Duc and Nadia Lamamra 5. Success, Well-Being and Social Recognition: An Interactional Perspective on Vocational Training Practices Stefano A. Losa, Barbara Duc and Laurent Filliettaz. 6. Agentic Pathways toward Fulfillment in Work Jeylan T. Mortimer, Mike Vuolo and Jeremy Staff 7. The How and Why of the Relationship between Job Insecuri-ty, Subjective Career Success, and Turnover Intention Cécile Tschopp and Gudela Grote 8. Work Experiences and Well-Being in the First Years of Professional Work in Switzerland: A Ten-Year Follow-up Study Wolfgang Kälin, Anita C. Keller, Franziska Tschan, Achim Elfering and Norbert K. Semmer 9. The Meaning and Measurement of Well-Being as an Indicator of Success Anita C. Keller, Norbert K. Semmer, Robin Samuel and Manfred Max Bergman

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Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of different influence factors (age, sex, weight, origin, breeding status) and a comparison of foot lesions between several zoological institutions and the feet of free-ranging Greater flamingos (Phoenicopterus roseus). A scoring system was used to determine the prevalence and types of lesions and severity. Cracks and nodules developed as early as 3 months of age and papillomatous growths as early as 6 to 7 months of age in captivity. Nodules with ulceration occurred significantly more often in birds older than 31 years and heavier than 4 kg. The comparison of different institutions revealed that birds kept in enclosures with natural-floored water ponds had significantly less severe lesions than birds kept in concrete water ponds. None of the free-ranging flamingos, which live on a muddy underground, showed any lesion. This study demonstrates that flooring, weight and age are important in the onset and progression of pododermatitis in flamingos.