969 resultados para disease marker


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BACKGROUND: The objective of this study was to link expression patterns of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1) and p16 to patient outcome (recurrence and survival) in a cohort of 252 patients with oral and oropharyngeal squamous cell cancer (OSCC). METHODS: Expression levels of Bmi-1 and p16 in samples from 252 patients with OSCC were evaluated immunohistochemically using the tissue microarray method. Staining intensity was determined by calculating an intensity reactivity score (IRS). Staining intensity and the localization of expression within tumor cells (nuclear or cytoplasmic) were correlated with overall, disease-specific, and recurrence-free survival. RESULTS: The majority of cancers were localized in the oropharynx (61.1%). In univariate analysis, patients who had OSCC and strong Bmi-1 expression (IRS >10) had worse outcomes compared with patients who had low and moderate Bmi-1 expression (P = .008; hazard ratio [HR], 1.82; 95% confidence interval [CI], 1.167-2.838); this correlation was also observed for atypical cytoplasmic Bmi-1 expression (P = .001; HR, 2.164; 95% CI, 1.389-3.371) and for negative p16 expression (P < .001; HR, 0.292; 95% CI, 0.178-0.477). The combination of both markers, as anticipated, had an even stronger correlation with overall survival (P < .001; HR, 8.485; 95% CI, 4.237-16.994). Multivariate analysis demonstrated significant results for patients with oropharyngeal cancers, but not for patients with oral cavity tumors: Tumor classification (P = .011; HR, 1.838; 95%CI, 1.146-2.947) and the combined marker expression patterns (P < .001; HR, 6.254; 95% CI, 2.869-13.635) were correlated with overall survival, disease-specific survival (tumor classification: P = .002; HR, 2.807; 95% CI, 1.477-5.334; combined markers: P = .002; HR, 5.386; 95% CI, 1.850-15.679), and the combined markers also were correlated with recurrence-free survival (P = .001; HR, 8.943; 95% CI, 2.562-31.220). CONCLUSIONS: Cytoplasmic Bmi-1 expression, an absence of p16 expression, and especially the combination of those 2 predictive markers were correlated negatively with disease-specific and recurrence-free survival in patients with oropharyngeal cancer. Therefore, the current results indicate that these may be applicable as predictive markers in combination with other factors to select patients for more aggressive treatment and follow-up. Cancer 2011;. © 2011 American Cancer Society.

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It is increasingly recognised that chronically activated glia contribute to the pathology of various neurodegenerative diseases, including glaucoma. One means by which this can occur is through the release of neurotoxic, proinflammatory factors. In the current study, we therefore investigated the spatio-temporal patterns of expression of three such cytokines, IL-1β, TNFα and IL-6, in a validated rat model of experimental glaucoma. First, only weak evidence was found for increased expression of IL-1β and TNFα following induction of ocular hypertension. Second, and much more striking, was that robust evidence was uncovered showing IL-6 to be synthesised by injured retinal ganglion cells following elevation of intraocular pressure and transported in an orthograde fashion along the nerve, accumulating at sites of axonal disruption in the optic nerve head. Verification that IL-6 represents a novel marker of disrupted axonal transport in this model was obtained by performing double labelling immunofluorescence with recognised markers of fast axonal transport. The stimulus for IL-6 synthesis and axonal transport during experimental glaucoma arose from axonal injury rather than ocular hypertension, as the response was identical after optic nerve crush and bilateral occlusion of the carotid arteries, each of which is independent of elevated intraocular pressure. Moreover, the response of IL-6 was not a generalised feature of the gp130 family of cytokines, as it was not mimicked by another family member, ciliary neurotrophic factor. Finally, further study suggested that IL-6 may be an early part of the endogenous regenerative response as the cytokine colocalised with growth-associated membrane phosphoprotein-43 in some putative regenerating axons, and potently stimulated neuritogenesis in retinal ganglion cells in culture, an effect that was additive to that of ciliary neurotrophic factor. These data comprise clear evidence that IL-6 is actively involved in the attempt of injured retinal ganglion cells to regenerate their axons.

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In the field of molecular and epidemiological parasitology, characterization of fast evolving genetic markers appears as an important challenge to consider the diversity and genetic structure of parasites. The study of respective populations can help us to understand their adaptive strategies to survive and perpetuate the species within different host populations, all trying to resist infection. In the past, the relative monomorphic features of Echinococcus multilocularis, the causative agent of alveolar echinococcosis and a severe human parasitic disease, did not stimulate studies dealing with the genetic variability of Echinococcus species or respective populations. A recently developed, characterized and validated original multilocus microsatellite, named EmsB, tandemly repeated in the genome, offered an additional opportunity for this line of investigation. We have compiled in this review new insights brought by this molecular tracker on the transmission activity of Echinococcus among different hosts and at different geographical scales.

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REASONS FOR PERFORMING STUDY: Sarcoids are nonmetastasising, yet locally aggressive skin tumours that constitute the most frequent neoplasm in equids. Infection by bovine papillomaviruses types 1 and 2 (BPV-1, BPV-2) has been recognised as major causative factor in sarcoid pathogenesis, but a possible correlation of intralesional virus load with disease severity has not been established thus far. HYPOTHESIS: Given the pathogenic role of BPV-1 and BPV-2 in sarcoid disease, we suggest that intralesional viral DNA concentration may reflect the degree of affection. METHODS: Severity of disease was addressed by recording the tumour growth kinetics, lesion number and tumour type for 37 sarcoid-bearing horses and one donkey. Viral load was estimated via quantitative real-time PCR (qPCR) of the E2, E5, L1 and L2 genes from the BPV-1/-2 genome for one randomly selected lesion per horse and correlated with disease severity. RESULTS: Quantitative PCR against E2 identified viral DNA concentrations ranging from 0-556 copies/tumour cell. Of 16 horses affected by quiescent, slowly growing single tumours or multiple mild-type lesions, 15 showed a viral load up to 1.4 copies per cell. In stark contrast, all equids (22/22) bearing rapidly growing and/or multiple aggressive sarcoids had a viral load between 3 and 569 copies per cell. Consistent results were obtained with qPCR against E5, L1 and L2. CONCLUSIONS: While tumours of the same clinical type carried variable virus load, confirming that viral titre does not determine clinical appearance, we identified a highly significant correlation between intralesional viral load and disease severity. POTENTIAL RELEVANCE: The rapid determination of BPV viral load will give a reliable marker for disease severity and may also be considered when establishing a therapeutic strategy.

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Low-intensity concentric (CET) and eccentric (EET) endurance-type training induce specific structural adaptations in skeletal muscle. We evaluated to which extent steady-state adaptations in transcript levels are involved in the compensatory alterations of muscle mitochondria and myofibrils with CET versus EET at a matched metabolic exercise intensity of medicated, stable coronary patients (CAD). Biopsies were obtained from vastus lateralis muscle before and after 8 weeks of CET (n=6) or EET (n=6). Transcript levels for factors involved in mitochondrial biogenesis (PGC-1alpha, Tfam), mitochondrial function (COX-1, COX-4), control of contractile phenotype (MyHC I, IIa, IIx) as well as mechanical stress marker (IGF-I) were quantified using an reverse-transcriptase polymerase chain reaction approach. After 8 weeks of EET, a reduction of the COX-4 mRNA level by 41% and a tendency for a drop in Tfam transcript concentration (-33%, P=0.06) was noted. This down-regulation corresponded to a drop in total mitochondrial volume density. MyHC-IIa transcript levels were specifically decreased after EET, and MyHC-I mRNA showed a trend towards a reduction (P=0.08). Total fiber cross-sectional area was not altered. After CET and EET, the IGF-I mRNA level was significantly increased. The PGC-1alpha significantly correlated with Tfam, and both PGC-1alpha and Tfam significantly correlated with COX-1 and COX-4 mRNAs. Post-hoc analysis identified significant interactions between the concurrent medication and muscular transcript levels as well as fiber size. Our findings support the concept that specific transcriptional adaptations mediate the divergent mitochondrial response of muscle cells to endurance training under different load condition and indicate a mismatch of processes related to muscle hypertrophy in medicated CAD patients.

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A marker that is strongly associated with outcome (or disease) is often assumed to be effective for classifying individuals according to their current or future outcome. However, for this to be true, the associated odds ratio must be of a magnitude rarely seen in epidemiological studies. An illustration of the relationship between odds ratios and receiver operating characteristic (ROC) curves shows, for example, that a marker with an odds ratio as high as 3 is in fact a very poor classification tool. If a marker identifies 10 percent of controls as positive (false positives) and has an odds ratio of 3, then it will only correctly identify 25 percent of cases as positive (true positives). Moreover, the authors illustrate that a single measure of association such as an odds ratio does not meaningfully describe a marker’s ability to classify subjects. Appropriate statistical methods for assessing and reporting the classification power of a marker are described. The serious pitfalls of using more traditional methods based on parameters in logistic regression models are illustrated.

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The heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been implicated in wound-healing processes of various tissues. However, it is not known whether HB-EGF may represent a factor implicated in overstimulated wound-healing processes of the retina during proliferative retinopathies. Therefore, we investigated whether human retinal pigment epithelial (RPE) cells, which are crucially involved in proliferative retinopathies, express and respond to HB-EGF. RPE cells express mRNAs for various members of the EGF-related growth factor family, among them for HB-EGF, as well as for the EGF receptors ErbB1, -2, -3, and -4. The gene expression of HB-EGF is stimulated in the presence of transforming and basic fibroblast growth factors and by oxidative stress and is suppressed during chemical hypoxia. Exogenous HB-EGF stimulates proliferation and migration of RPE cells and the gene and protein expression of the vascular endothelial growth factor (VEGF). HB-EGF activates at least three signal transduction pathways in RPE cells including the extracellular signal-regulated kinases (involved in the proliferation-stimulating action of HB-EGF), p38 (mediates the effects on chemotaxis and secretion of VEGF), and the phosphatidylinositol-3 kinase (necessary for the stimulation of chemotaxis). In epiretinal membranes of patients with proliferative retinopathies, HB-EGF immunoreactivity was partially colocalized with the RPE cell marker, cytokeratins; this observation suggests that RPE cell-derived HB-EGF may represent one factor that drives the uncontrolled wound-healing process of the retina. The stimulating effect on the secretion of VEGF may suggest that HB-EGF is also implicated in the pathological angiogenesis of the retina.

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STUDY OBJECTIVE: Caregiving for a relative with Alzheimer disease has been associated with sympathoadrenal medullary arousal and morbidity and mortality. In this study, we examined if sleep disturbance of elderly caregivers was associated with physiologic markers of cardiovascular risk, including plasma norepinephrine, epinephrine, and the hemostasis marker D-dimer. DESIGN: Cross-sectional. SETTING: Community-based sample of elderly caregivers of spouses with Alzheimer disease assessed within their homes. PARTICIPANTS: A sample of 40 elderly spousal caregivers of patients with Alzheimer disease. MEASUREMENTS AND RESULTS: Participants underwent in-home full-night polysomnography and had plasma assayed for norepinephrine and epinephrine. Using multiple regression analyses and controlling for a number of cardiovascular risk factors (e.g., age, sex, blood pressure, body mass index), increased wake after sleep onset was positively associated with norepinephrine levels (beta = .35; t = 2.45, df = 32, p = .020) and plasma D-dimer (beta = .31; t = 2.18, df = 29, p = .038). Further, plasma norepinephrine was significantly associated with D-dimer (beta = .34; t = 2.11, df = 29, p = .044). Additional analyses indicated that norepinephrine accounted for 28% of the relationship between wake after sleep onset and D-dimer. No association was observed between sleep variables and epinephrine. CONCLUSIONS: These findings provide preliminary evidence that sleep disturbance may contribute to morbidity in caregivers through sympathoadrenal medullary arousal and downstream physiologic effects such as altering the hemostasis environment.

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AIMS: We investigated whether myeloid-related protein 8/14 complex (MRP8/14) expressed by infiltrating monocytes and granulocytes may represent a mediator and early biomarker of acute coronary syndromes (ACS). METHODS AND RESULTS: Immunohistochemistry of coronary thrombi was done in 41 ACS patients. Subsequently, levels of MRP8/14 were assessed systemically in 75 patients with ACS and culprit lesions, with stable coronary artery disease (CAD), or with normal coronary arteries. In a subset of patients, MRP8/14 was measured systemically and at the site of coronary occlusion. Macrophages and granulocytes, but not platelets stained positive for MRP8/14 in 76% of 41 thrombi patients. In ACS, local MRP8/14 levels [22.0 (16.2-41.5) mg/L] were increased when compared with systemic levels [13.4 (8.1-14.7) mg/L, P = 0.03]. Systemic levels of MRP8/14 were markedly elevated [15.1 (12.1-21.8) mg/L, P = 0.001] in ACS when compared with stable CAD [4.6 (3.5-7.1) mg/L] or normals [4.8 (4.0-6.3) mg/L]. Using a cut-off level of 8 mg/L, MRP8/14 but not myoglobin or troponin, identified ACS presenting within 3 h from symptom onset. CONCLUSION: In ACS, MRP8/14 is markedly expressed at the site of coronary occlusion by invading phagocytes. The occurrence of elevated MRP8/14 in the systemic circulation prior to markers of myocardial necrosis makes it a prime candidate for the detection of unstable plaques and management of ACS.

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BACKGROUND: Activation of the cytokine and the complement system is associated with disease progression in severe congestive heart failure (CHF). Magnitude and prognostic relevance of cytokine and complement activation remain uncertain in patients with moderate CHF. OBJECTIVES: Measurement of cytokine and complement activation in patients with moderate CHF and testing whether C-reactive protein (CRP) can serve as a surrogate marker of their activation, adding independent prognostic information when co-measured with B-type natriuretic peptide (BNP). METHODS: The 118 study participants were separated into three groups based on pre-determined CRP and BNP levels: Group I (n = 27; CRP > 5 mg/liter, BNP > or = 200 pg/ml); Group II (n = 46; CRP < or = 5 mg/liter, BNP > or = 200 pg/ml); and Group III (n = 45; CRP < or = 5 mg/liter, BNP < 200 pg/ml). RESULTS: Mortality was high in Group I (30%; log-rank p < 0.001) but low in Groups II and III (2% and 4%, respectively; log rank, p = 0.7). No differences were observed for left ventricular ejection fraction (LVEF) and left ventricular end-diastolic diameter (LVEDD) between Groups I and II (31 +/- 16 vs 32 +/- 14% and 66 +/- 16 vs 65 +/- 11 mm, respectively), whereas in Group III LVEF was higher (42 +/- 17%, p = 0.002) with smaller LVEDD (57 +/- 13 mm, p = 0.012). Cytokine sCD14 and tumor necrosis factor (TNF)-alpha levels were not different between the three groups. However, interleukin-6 levels (9.75 +/- 8.17 pg/ml, p = 0.001) and the terminal complement complex C5b-9 (109.9 +/- 68 ng/ml; p = 0.04) were elevated in Group I, both correlating with CRP (interleukin-6: r = 0.5, p < 0.001; C5b-9: r = 0.41, p = 0.001). CONCLUSIONS: CRP may be used as a surrogate parameter for interleukin-6 and complement activation in moderate CHF. CRP in combination with BNP identifies a high-risk group with a tendency for poor outcome not discriminated by cardiac function.

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Melatonin has been postulated to have diverse properties, acting as an antioxidant, a neuroprotector, or a stabilizer within the circadian timing system, and is thus thought to be involved in the aging process and Alzheimer's disease (AD). We used computed tomography to determine the degree of pineal calcification (DOC), an intra-individual melatonin deficit marker, as well as the size of uncalcified pineal tissue, in 279 consecutive memory clinic outpatients (AD: 155; other dementia: 25; mild cognitive impairment: 33; depression: 66) and 37 age-matched controls. The size of uncalcified pineal tissue in patients with AD (mean 0.15 cm(2) [S.D. 0.24]) was significantly smaller than in patients with other types of dementia (0.26 [0.34]; P=0.038), with depression (0.28 [0.34]; P=0.005), or in controls (0.25 [0.31]; P=0.027). Additionally, the DOC in patients with AD (mean 76.2% [S.D. 26.6]) was significantly higher than in patients with other types of dementia (63.7 [34.7]; P=0.042), with depression (60.5 [33.8]; P=0.001), or in controls (64.5 [30.6]; P=0.021). These two findings may reflect two different aspects of melatonin in AD. On the one hand, the absolute amount of melatonin excretion capability, as indicated by uncalcified pineal volume, refers to the antioxidant properties of melatonin. On the other hand, the relative reduction in melatonin production capability in the individual, as indicated by DOC, refers to the circadian properties of melatonin.

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AIMS/HYPOTHESIS: Retinol-binding protein 4 (RBP4) has recently been reported to be associated with insulin resistance and the metabolic syndrome. This study tested the hypothesis that RBP4 is a marker of insulin resistance and the metabolic syndrome in patients with type 2 diabetes or coronary artery disease (CAD) or in non-diabetic control subjects without CAD. METHODS: Serum RBP4 was measured in 365 men (126 with type 2 diabetes, 143 with CAD and 96 control subjects) and correlated with the homeostasis model assessment of insulin resistance index (HOMA-IR), components of the metabolic syndrome and lipoprotein metabolism. RBP4 was detected by ELISA and validated by quantitative Western blotting. RESULTS: RBP4 concentrations detected by ELISA were shown to be strongly associated with the results gained in quantitative Western blots. There were no associations of RBP4 with HOMA-IR or HbA(1c) in any of the groups studied. In patients with type 2 diabetes there were significant positive correlations of RBP4 with total cholesterol, LDL-cholesterol, VLDL-cholesterol, plasma triacylglycerol and hepatic lipase activity. In patients with CAD, there were significant associations of RBP4 with VLDL-cholesterol, plasma triacylglycerol and hepatic lipase activity, while non-diabetic control subjects without CAD showed positive correlations of RBP4 with VLDL-cholesterol and plasma triacylglycerol. CONCLUSIONS/INTERPRETATION: RBP4 does not seem to be a valuable marker for identification of the metabolic syndrome or insulin resistance in male patients with type 2 diabetes or CAD. Independent associations of RBP4 with pro-atherogenic lipoproteins and enzymes of lipoprotein metabolism indicate a possible role of RBP4 in lipid metabolism.

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OBJECTIVE: Adiponectin has anti-atherogenic properties and low circulating adiponectin has been linked to coronary atherosclerosis. Yet, there is considerable evidence that the high-molecular weight (HMW) complex of adiponectin is the major active form of this adipokine. We therefore investigated whether HMW adiponectin is associated with the extent of coronary artery disease (CAD) in men. RESEARCH DESIGN AND METHODS: Associations among CAD, HMW adiponectin and the HMW/total-adiponectin ratio were assessed in 240 male patients undergoing elective coronary angiography. Total adiponectin and HMW adiponectin was measured by enzyme-linked immunosorbent assay and serum levels were correlated with defined coronary scores and established cardiovascular risk factors. RESULTS: We found significant inverse correlations between angiographic scores and HMW adiponectin [Extent Score (ES): r=-0.39; Gensini Score (GS): r=-0.35; and Severity Score (SS): r=-0.40, all P<0.001], and the HMW/total-adiponectin ratio (ES: r=-0.49; GS: r=-0.46; SS: r=-0.46; all P<0.001). Multivariable regression analyses revealed that HMW adiponectin and the HMW/total-adiponectin ratio were significantly associated with the extent of CAD (both P<0.001). ROC analyses demonstrated that the predictive value of HMW adiponectin and the HMW/total-adiponectin ratio for the extent of coronary atherosclerosis significantly exceeded that of total adiponectin (P<0.001, P=0.010, respectively). CONCLUSIONS: HMW adiponectin and the HMW/total-adiponectin ratio inversely correlate with the extent of CAD. HMW adiponectin in particular seems to be a better marker for CAD extent than total adiponectin.

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OBJECTIVES: In this study we tested the hypothesis that lipopolysaccharide-binding protein (LBP) might be able to be used as a biomarker for coronary artery disease (CAD). BACKGROUND: The mechanisms by which the innate immune recognition of pathogens could lead to atherosclerosis remain unclear. Lipopolysaccharide-binding protein is the first protein to encounter lipopolysaccharide and to deliver it to its cellular targets, toll-like receptors; therefore, its presence might be a reliable biomarker that indicates activation of innate immune responses. METHODS: A total of 247 men undergoing elective coronary angiography were studied, and the extent of coronary atherosclerosis was assessed by 2 established scores: "extent score" and "severity score." Levels of LBP, markers of inflammation, and traditional risk factors for CAD were assessed. RESULTS: Serum LBP concentration was significantly increased in 172 patients with angiographically confirmed CAD compared with 75 individuals without coronary atherosclerosis (20.6 +/- 8.7 pg/ml vs. 17.1 +/- 6.0 pg/ml, respectively; p = 0.002). Moreover in multivariable logistic regression analyses, adjusted for established cardiovascular risk factors and markers of systemic inflammation, LBP was a significant and independent predictor of prevalent CAD (p < 0.05 in all models). CONCLUSIONS: Lipopolysaccharide-binding protein might serve as a novel marker for CAD in men. The present results underlie the potential importance of innate immune mechanisms for CAD. Further studies are warranted to bolster the data and to identify pathogenetic links between innate immune system activation and atherosclerosis.

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While it is well established that proximity to wetlands is a risk factor for contracting Buruli ulcer, it is not clear what proportion of a population living in an area where the etiologic agent, Mycobacterium ulcerans, is endemic is actually exposed to this disease. Immunological cross-reactivity among mycobacterial species complicates the development of a specific serological test. Among immunodominant proteins recognized by a panel of anti-M. ulcerans monoclonal antibodies, the M. ulcerans homologue of the M. leprae 18-kDa small heat shock protein (shsp) was identified. Since this shsp has no homologues in M. bovis and M. tuberculosis, we evaluated its use as a target antigen for a serological test. Anti-18-kDa shsp antibodies were frequently found in the sera of Buruli ulcer patients and of healthy household contacts but rarely found in controls from regions where the infection is not endemic. The results indicate that only a small proportion of M. ulcerans-infected individuals contract the clinical disease.