932 resultados para Relative condition factor


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Background Matrix metalloproteinase (MMP)-9 is an endopeptidase that digests basement membrane type-IV collagen. Enhanced expression has been related to tumour progression in a number of systems. The control of MMP expression is complex, but recently epidermal growth actor receptor (EGFR) activity has been implicated in up-regulation of MMP-9 in tumour cells in vitro. Aims To evaluate interrelations between MMP-9 and EGFR expression in non-small cell lung cancer (NSCLC) and to assess the impact of expression on survival. Methods This is a retrospective study of 152 patients who underwent resection for stage I-IIIa NSCLC with a post-operative survival >60 days. Minimum follow-up was 2 years. Standard ABC immunohistochemistry was performed on 4μm paraffin-embedded sections from the tumour periphery using monoclonal antibodies to MMP-9 and EGFR. Results: MMP-9 was expressed in the tumour cells of 79/152 (52%) cases. EGFR expression was found in 86/152 (57%) cases [membranous 51/152 (34%), cytoplasmic 35/152 (23%)]. MMP-9 expression was associated with poor outcome (p=0.04). Membranous, cytoplasmic and overall EGFR expression were not associated with outcome (p=0.29, p=0.85 and p=0.41 respectively). There was a strong correlation between MMP-9 expression and EGFR expression (p=0.001) and EGFR membranous expression (p=0.01) but not with cytoplasmic EGFR expression (p=0.28). Co-expression of MMP-9 and EGFR (36%) conferred a worse prognosis (p=0.003). Subset analysis revealed only MMP-9 and membranous EGFR co-expression (22%) was associated with poor outcome (p=0.008). Conclusions Our results show that MMP-9 and EGFR are co-expressed in NSCLC. This finding suggests the EGFR signalling pathway may play an important role in the invasive behaviour of NSCLC via specific upregulation of MMP-9. The co-expression of these markers also confers a poor prognosis.

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Growth and metastatic spread of invasive carcinoma depends on angiogenesis, the formation of new blood vessels. Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic growth factor for a number of solid tumors, including lung, bladder, colorectal, and renal cell cancer. Cervical intraepithelial neoplasia (CIN) is the precursor to squamous cell cervical carcinoma (SCC). Mean vessel density (MVD) increases from normal cervical tissue, through low- and high-grade CIN to SCC. We evaluated PD-ECGF immunoreactivity and correlated its expression with MVD in normal, premalignant, and malignant cervical tissue. PD-ECGF expression was assessed visually within the epithelial tissues and scored on the extent and intensity of staining. MVD was calculated by counting the number of vessels positive for von Willebrand factor per unit area subtending normal or CIN epithelium or within tumor hotspots for SCC. Cytoplasmic and/or nuclear PD-ECGF immunoreactivity was seen in normal epithelium. PD-ECGF expression significantly increased with histologic grade from normal, through low- and high-grade CIN, to SCC (P < .02). A progressive significant increase in the microvessel density was also seen, ranging from a mean of 28 vessels for normal tissue to 57 for SCC (P < .0005). No correlation was found between PD-ECGF expression and MVD (P = .45). We conclude that PD-ECGF expression and MVD increase as the cervix transforms from a normal to a malignant phenotype. PD-ECGF is thymidine phosphorylase, a key enzyme in the activation of fluoropyrimidines, including 5-fluorouracil. Evaluation of PD-ECGF thymidine phosphorylase expression may be important in designing future chemotherapeutic trials in cervical cancer. Copyright (C) 2000 by W.B. Saunders Company.

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Angiogenesis is essential for tumour growth beyond 1 to 2 mm in diameter. The clinical relevance of angiogenesis, as assessed by microvessel density (MVD), is unclear in malignant mesothelioma (MM). Immunohistochemistry was performed on 104 archival, paraffin-embedded, surgically resected MM samples with an anti-CD34 monoclonal antibody, using the Streptavidin-biotin complex immunoperoxidase technique. 93 cases were suitable for microvessel quantification. MVD was obtained from 3 intratumoural hotspots, using a Chalkley eyepiece graticule at × 250 power. MVD was correlated with survival by Kaplan-Meier and log-rank analysis. A stepwise, multivariate Cox model was used to compare MVD with known prognostic factors and the EORTC and CALGB prognostic scoring systems. Overall median survival from the date of diagnosis was 5.0 months. Increasing MVD was a poor prognostic factor in univariate analysis (P = 0.02). Independent indicators of poor prognosis in multivariate analysis were non-epithelial cell type (P = 0.002), performance status > 0 (P = 0.003) and increasing MVD (P = 0.01). In multivariate Cox analysis, MVD contributed independently to the EORTC (P = 0.006), but not to the CALGB (P = 0.1), prognostic groups. Angiogenesis, as assessed by MVD, is a poor prognostic factor in MM, independent of other clinicopathological variables and the EORTC prognostic scoring system. Further work is required to assess the prognostic importance of angiogenic regulatory factors in this disease. © 2001 Cancer Research Campaign.

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Platelet-derived endothelial cell growth factor/thymidine phosphorylase (PD-ECGF/TP) is an enzyme with angiogenic and cell motility properties. Moreover, it is involved in the transformation of fluoropyrimidines into active cytotoxic metabolites, In the present study, the expression of PD-ECGF in normal lung and lung cancer was immunohistochemically evaluated using the P-GF.44C monoclonal antibody. Alveolar and tumoural macrophages mere invariably stained and mere used as an internal control for assessment of the staining. Alveolar epithelium was always negative, whilst bronchiolar epithelium showed occasional positive reactivity. Normal lung and tumour endothelium was occasionally positive, Positive staining in more than 50 per cent of cells was observed in 23/71 squamous carcinomas (32 per cent), 16/38 (42 per cent) adenocarcinomas, and 2/6 (33 per cent) adenosquamous carcinomas. Differentiated areas and areas of squamous metaplasia mere more strongly positive than other tumour areas. All 22 small cell carcinomas and one carcinoid tumour were negative. The present study provides a baseline for future studies in non-small cell lung cancer to correlate PD-ECGF expression with tumour vascularization, prognosis, and response to chemotherapy.

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Purpose: This randomized, multicenter trial compared first-line trastuzumab plus docetaxel versus docetaxel alone in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). Patients and Methods: Patients were randomly assigned to six cycles of docetaxel 100 mg/m 2 every 3 weeks, with or without trastuzumab 4 mg/kg loading dose followed by 2 mg/kg weekly until disease progression. Results: A total of 186 patients received at least one dose of the study drug. Trastuzumab plus docetaxel was significantly superior to docetaxel alone in terms of overall response rate (61% v 34%; P = .0002), overall survival (median, 31.2 v 22.7 months; P = .0325), time to disease progression (median, 11.7 v 6.1 months; P = .0001), time to treatment failure (median, 9.8 v 5.3 months; P = .0001), and duration of response (median, 11.7 v 5.7 months; P = .009). There was little difference in the number and severity of adverse events between the arms. Grade 3 to 4 neutropenia was seen more commonly with the combination (32%) than with docetaxel alone (22%), and there was a slightly higher incidence of febrile neutropenia in the combination arm (23% v 17%). One patient in the combination arm experienced symptomatic heart failure (1%). Another patient experienced symptomatic heart failure 5 months after discontinuation of trastuzumab because of disease progression, while being treated with an investigational anthracycline for 4 months. Conclusion: Trastuzumab combined with docetaxel is superior to docetaxel alone as first-line treatment of patients with HER2-positive MBC in terms of overall survival, response rate, response duration, time to progression, and time to treatment failure, with little additional toxicity. © 2005 by American Society of Clinical Oncology.

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Purpose: PTK787/ZK 222584 (PTK/ZK), an orally active inhibitor of vascular endothelial growth factor (VEGF) receptor tyrosine kinases, inhibits VEGF-mediated angiogenesis. The pharmacodynamic effects of PTK/ZK were evaluated by assessing changes in contrast-enhancement parameters of metastatic liver lesions using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in patients with advanced colorectal cancer treated in two ongoing, dose-escalating phase I studies. Patients and Methods: Twenty-six patients had DCE-MRI performed at baseline, day 2, and at the end of each 28-day cycle. Doses of oral PTK/ZK ranged from 50 to 2000 mg once daily. Tumor permeability and vascularity were assessed by calculating the bidirectional transfer constant (Ki). The percentage of baseline Ki (% of baseline Ki) at each time point was compared with pharmacokinetic and clinical end points. Results: A significant negative correlation exists between the % of baseline Ki and increase in PTK/ZK oral dose and plasma levels (P = .01 for oral dose; P = .0001 for area under the plasma concentration curve at day 2). Patients with a best response of stable disease had a significantly greater reduction in Ki at both day 2 and at the end of cycle 1 compared with progressors (mean difference in % of baseline Ki, 47%, P = .004%; and 51%, P = .006; respectively). The difference in % of baseline Ki remained statistically significant after adjusting for baseline WHO performance status. Conclusion: These findings should help to define a biologically active dose of PTK/ZK. These results suggest that DCE-MRI may be a useful biomarker for defining the pharmacological response and dose of angiogenesis inhibitiors, such as PTK/ZK, for further clinical development. © 2003 by American Society of Clinical Oncology.

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Recent studies have demonstrated that angiogenesis and suppressed cell- mediated immunity (CMI) play a central role in the pathogenesis of malignant disease facilitating tumour growth, invasion and metastasis. In the majority of tumours, the malignant process is preceded by a pathological condition or exposure to an irritant which itself is associated with the induction of angiogenesis and/or suppressed CMI. These include: cigarette smoking, chronic bronchitis and lung cancer; chronic oesophagitis and oesophageal cancer; chronic viral infections such as human papilloma virus and ano-genital cancers, chronic hepatitis B and C and hepatocellular carcinoma, and Epstein- Barr virus (EBV) and lymphomas; chronic inflammatory conditions such as Crohn's disease and ulcerative colitis and colorectal cancer; asbestos exposure and mesothelioma and excessive sunlight exposure/sunburn and malignant melanoma. Chronic exposure to growth factors (insulin-like growth factor-I in acromegaly), mutations in tumour suppressor genes (TP53 in Li Fraumeni syndrome) and long-term exposure to immunosuppressive agents (cyclosporin A) may also give rise to similar environments and are associated with the development of a range of solid tumours. The increased blood supply would facilitate the development and proliferation of an abnormal clone or clones of cells arising as the result of: (a) an inherited genetic abnormality; and/or (b) acquired somatic mutations, the latter due to local production and/or enhanced delivery of carcinogens and mutagenic growth factors. With progressive detrimental mutations and growth-induced tumour hypoxia, the transformed cell, to a lesser or greater extent, may amplify the angiogenic process and CMI suppression, thereby facilitating further tumour growth and metastasis. There is accumulating evidence that long-term treatment with cyclo-oxygenase inhibitors (aspirin and indomethacin), cytokines such as interferon-α, anti-oestrogens (tamoxifen and raloxifene) and captopril significantly reduces the incidence of solid tumours such as breast and colorectal cancer. These agents are anti-angiogenic and, in the case of aspirin, indomethacin and interferon-α have proven immunomodulatory effects. Collectively these observations indicate that angiogenesis and suppressed CMI play a central role in the development and progression of malignant disease. (C) 2000 Elsevier Science Ltd.

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Objective Do employees care about their relative (economic) position in comparison to their co-workers in an organization? And if so, does it raise or lower their performance? While the topic is widely discussed in the literature, behavioral evidence on these important questions is relatively rare. Methods This article explores the pay-performance relationship using a sports data set. The strength of analyzing such data is that sports tournaments take place in a very controlled environment that helps to isolate a relative income effect. Results Using two large unique data sets that cover 26 seasons in basketball and eight seasons in soccer (Bundesliga), we find considerable support for the idea that a relative income disadvantage is correlated with a decrease in individual performance. In addition, there does not seem to be any tolerance for income disparity based on the hope that such differences may signal that better times are ahead. Conclusions This suggests the need to consider the impact of the relative income position when designing pay-for-performance mechanisms within firms and teams.

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Both cyclooxygenase (COX)-2 and epidermal growth factor receptor (EGFR) are thought to play important roles in the pathogenesis of non-small cell lung cancer (NSCLC). A number of in vitro studies have postulated a link between EGFR activation and subsequent COX-2 upregulation. The relationship between these factors has not been established in patients with NSCLC. COX-2 and EGFR expression were studied in 172 NSCLC specimens using standard immunohistochemical techniques. Western blotting was used to determine COX-2 and EGFR levels in five NSCLC cell lines. The effect of treatment with EGF on COX-2 expression in A549 cells was assessed. Results: Both EGFR and COX-2 are overexpressed in NSCLC. The predominant pattern of COX-2 and EGFR staining was cytoplasmic. Membranous EGFR staining was seen in 23.3% of cases. There was no relationship between COX-2 and EGFR expression and survival or any clinicopathological features. No correlation was seen between EGFR expression and COX-2 expression in the immunohistochemical series or in the cell lines. Treatment with EGF did not upregulate COX-2 levels in A549 cells, either in serum free or serum-supplemented conditions. Conclusions: Although COX-2 and EGFR are over-expressed in NSCLC neither was of prognostic significance in this series of cases. There is no correlation between these two factors in either tumour samples or cell lines. Although these factors show no correlation in NSCLC, they remain potential, though independent targets for treatment. © 2004 Elsevier Ireland Ltd. All rights reserved.

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The epidermal growth factor receptor (EGFR) is part of a family of plasma membrane receptor tyrosine kinases that control many important cellular functions, from growth and proliferation to cell death. Cyclooxygenase (COX)-2 is an enzyme which catalyses the conversion of arachidonic acid to prostagladins and thromboxane. It is induced by various inflammatory stimuli, including the pro-inflammatory cytokines, Interleukin (IL)-1β, Tumour Necrosis Factor (TNF)-α and IL-2. Both EGFR and COX-2 are over-expressed in non-small cell lung cancer (NSCLC) and have been implicated in the early stages of tumourigenesis. This paper considers their roles in the development and progression of lung cancer, their potential interactions, and reviews the recent progress in cancer therapies that are directed toward these targets. An increasing body of evidence suggests that selective inhibitors of both EGFR and COX-2 are potential therapeutic agents for the treatment of NSCLC, in the adjuvant, metastatic and chemopreventative settings. © 2002 Elsevier Science Ireland Ltd. All rights reserved.

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Family members living with a relative diagnosed with schizophrenia have reported challenges and traumatic stressors, as well as perceived benefits and personal growth. This study explored factors associated with posttraumatic growth (PTG) within such families. Personality, stress, coping, social support and PTG were assessed in 110 family members. Results revealed that a multiplicative mediational path model with social support and emotional or instrumental coping strategies as multi-mediators had a significant indirect effect on the relationship between extraversion and PTG. Clinically relevant concepts that map onto the multi-mediator model are discussed, translating these findings into clinical practice to facilitate naturally occurring PTG processes.

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iTRAQ (isobaric tags for relative or absolute quantitation) is a mass spectrometry technology that allows quantitative comparison of protein abundance by measuring peak intensities of reporter ions released from iTRAQ-tagged peptides by fragmentation during MS/MS. However, current data analysis techniques for iTRAQ struggle to report reliable relative protein abundance estimates and suffer with problems of precision and accuracy. The precision of the data is affected by variance heterogeneity: low signal data have higher relative variability; however, low abundance peptides dominate data sets. Accuracy is compromised as ratios are compressed toward 1, leading to underestimation of the ratio. This study investigated both issues and proposed a methodology that combines the peptide measurements to give a robust protein estimate even when the data for the protein are sparse or at low intensity. Our data indicated that ratio compression arises from contamination during precursor ion selection, which occurs at a consistent proportion within an experiment and thus results in a linear relationship between expected and observed ratios. We proposed that a correction factor can be calculated from spiked proteins at known ratios. Then we demonstrated that variance heterogeneity is present in iTRAQ data sets irrespective of the analytical packages, LC-MS/MS instrumentation, and iTRAQ labeling kit (4-plex or 8-plex) used. We proposed using an additive-multiplicative error model for peak intensities in MS/MS quantitation and demonstrated that a variance-stabilizing normalization is able to address the error structure and stabilize the variance across the entire intensity range. The resulting uniform variance structure simplifies the downstream analysis. Heterogeneity of variance consistent with an additive-multiplicative model has been reported in other MS-based quantitation including fields outside of proteomics; consequently the variance-stabilizing normalization methodology has the potential to increase the capabilities of MS in quantitation across diverse areas of biology and chemistry.

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This paper examines the dynamic behaviour of relative prices across seven Australian cities by applying panel unit root test procedures with structural breaks to quarterly consumer price index data for 1972 Q1–2011 Q4. We find overwhelming evidence of convergence in city relative prices. Three common structural breaks are endogenously determined at 1985, 1995, and 2007. Further, correcting for two potential biases, namely Nickell bias and time aggregation bias, we obtain half-life estimates of 2.3–3.8 quarters that are much shorter than those reported by previous research. Thus, we conclude that both structural breaks and bias corrections are important to obtain shorter half-life estimates.

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The epidermal growth factor receptor (EGFR) is commonly expressed in non-small-cell lung cancer (NSCLC) and promotes a host of mechanisms involved in tumorigenesis. However, EGFR expression does not reliably predict prognosis or response to EGFR-targeted therapies. The data from two previous studies of a series of 181 consecutive surgically resected stage I-IIIA NSCLC patients who had survived in excess of 60 days were explored. Of these patients, tissue was available for evaluation of EGFR in 179 patients, carbonic anhydrase (CA) IX in 177 patients and matrix metalloproteinase-9 (MMP-9) in 169 patients. We have previously reported an association between EGFR expression and MMP-9 expression. We have also reported that MMP-9 (P=0.001) and perinuclear (p)CA IX (P=0.03) but not EGFR expression were associated with a poor prognosis. Perinuclear CA IX expression was also associated with EGFR expression (P<0.001). Multivariate analysis demonstrated that coexpression of MMP-9 with EGFR conferred a worse prognosis than the expression of MMP-9 alone (P<0.001) and coexpression of EGFR and pCA IX conferred a worse prognosis than pCA IX alone (P=0.05). A model was then developed where the study population was divided into three groups: group 1 had expression of EGFR without coexpression of MMP-9 or pCA IX (number=21); group 2 had no expression of EGFR (number=75); and group 3 had coexpression of EGFR with pCA IX or MMP-9 or both (number=70). Group 3 had a worse prognosis than either groups 1 or 2 (P=0.0003 and 0.027, respectively) and group 1 had a better prognosis than group 2 (P=0.036). These data identify two cohorts of EGFR-positive patients with diametrically opposite prognoses. The group expressing either EGFR and or both MMP-9 and pCA IX may identify a group of patients with activated EGFR, which is of clinical relevance with the advent of EGFR-targeted therapies. © 2004 Cancer Research UK.