The present study aimed to verify a possibility of ongoing lymphangiogenesis in non-small cell lung cancer (NSCLC) via examination of mRNA levels of a number of lymphangiogenesis-associated genes in tumors. It was hypothesized that transcriptional activation of these genes would occur in tumors that stimulate new lymphatic vessel formation. The study was performed on 140 pairs of fresh-frozen surgical specimens of cancer and unaffected lung tissues derived from NSCLC stage I-IIIA patients.
View Article and Find Full Text PDFImproving the electrode-neuron interface to reduce current spread between individual electrodes has been identified as one of the main objectives in the search for future improvements in cochlear-implant performance. Here, we address this problem by presenting a novel stimulation strategy that takes account of the biophysical properties of the auditory neurons (spiral ganglion neurons, SGNs) stimulated in electrical hearing. This new strategy employs a ramped pulse shape, where the maximum amplitude is achieved through a linear slope in the injected current.
View Article and Find Full Text PDFMusical notes can be ordered from low to high along a perceptual dimension called "pitch". A characteristic property of these sounds is their periodic waveform, and periodicity generally correlates with pitch. Thus, pitch is often described as the perceptual correlate of the periodicity of the sound's waveform.
View Article and Find Full Text PDFAn important task performed by a neuron is the selection of relevant inputs from among thousands of synapses impinging on the dendritic tree. Synaptic plasticity enables this by strenghtening a subset of synapses that are, presumably, functionally relevant to the neuron. A different selection mechanism exploits the resonance of the dendritic membranes to preferentially filter synaptic inputs based on their temporal rates.
View Article and Find Full Text PDFDetermining the electrical stimulation levels is often a difficult and time-consuming task because they are normally determined behaviorally - a particular challenge when dealing with pediatric patients. The evoked stapedius reflex threshold and the evoked compound action potential have already been shown to provide reasonable estimates of the C- and T-levels, although these estimates tend to overestimate the C- and T-levels. The aim of this study was to investigate whether the evoked auditory brainstem response (eABR) can also be used to reliably estimate a patient's C- and T-levels.
View Article and Find Full Text PDFObjective: Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are present in esophageal cancer cells. Moreover the total activity of ADH as well as the activity of class IV ADH isoenzyme is significantly higher in cancer tissue than in healthy mucosa. The activity of these enzymes in cancer cells is reflected in the sera and could thus be helpful for diagnostics of esophageal cancer.
View Article and Find Full Text PDFA major goal in auditory neuroscience is to characterize how communication sounds are represented at the cortical level. The present review aims at investigating the role of auditory cortex in the processing of speech, bird songs and other vocalizations, which all are spectrally and temporally highly structured sounds. Whereas earlier studies have simply looked for neurons exhibiting higher firing rates to particular conspecific vocalizations over their modified, artificially synthesized versions, more recent studies determined the coding capacity of temporal spike patterns, which are prominent in primary and non-primary areas (and also in non-auditory cortical areas).
View Article and Find Full Text PDFThe positive expression of MMP-2 and TIMP-2 were found in esophageal cancer (EC) tissue and correlated with cancer stage and clinico-pathological features of tumor and patients' survival. However, little is known about serum levels of those proteins in EC patients. The aim of the present study was to investigate the diagnostic significance of MMP-2 and TIMP-2 serum levels in EC patients in relation to clinico-pathological features of cancer.
View Article and Find Full Text PDFSpectro-temporal properties of auditory cortex neurons have been extensively studied with artificial sounds but it is still unclear whether they help in understanding neuronal responses to communication sounds. Here, we directly compared spectro-temporal receptive fields (STRFs) obtained from the same neurons using both artificial stimuli (dynamic moving ripples, DMRs) and natural stimuli (conspecific vocalizations) that were matched in terms of spectral content, average power and modulation spectrum. On a population of auditory cortex neurons exhibiting reliable tuning curves when tested with pure tones, significant STRFs were obtained for 62% of the cells with vocalizations and 68% with DMR.
View Article and Find Full Text PDFElevated C-reactive protein (CRP) levels have been found in patients with several malignancies. The aim of the present study was to analyze the diagnostic and prognostic values of CRP levels measurement in esophageal cancer (EC) patients in relation to its different histological subtypes (squamous cell carcinoma-ESCC and adenocarcinoma-AC of esophagus) and compared them with classic tumor markers-carcinoembryonic antigen (CEA) and squamous cell cancer antigen (SCC-Ag). The diagnostic sensitivity, specificity, and the areas under receiver operating characteristic curves (AUC) for all the proteins tested were defined.
View Article and Find Full Text PDFIt has been suggested that interleukin 6 (IL-6) plays a potential role in the growth and progression of tumors, including esophageal cancer (EC). The aim of the study was to compare clinical significance of serum IL-6 with classic tumor markers - carcinoembryonic antigen (CEA) and squamous cell cancer antigen (SCC-Ag) - in EC patients in relation to its histological types - squamous cell carcinoma of esophagus (ESCC) and adenocarcinoma (AD) of esophagus. The study included 53 EC patients and 90 healthy subjects.
View Article and Find Full Text PDFThe discovery of markers to lymphatic endothelial cells and the development of novel antibodies to these markers have brought increasing attention to the lymphatics and progress in the understanding of lymphangiogenesis and cancer metastasis. In this study, we investigate the presence of lymphatic vessel invasion (LVI) detected by D2-40 immunohistochemical staining in resected esophageal cancer and correlated with clinicopathologic data and patient survival. Sixty nine patients, who had a primary resection of esophageal cancer, were analyzed by univariate and multivariate logistic regression, and univariate and multivariate survival analysis.
View Article and Find Full Text PDFVascular endothelial growth factors C (VEGF-C) and D (VEGF-D) are important lymphangiogenic factors in human cancers. We studied the expression of VEGF-C and VEGF-D using immunohistochemistry in 73 resected esophageal cancer specimens, and correlated the results with patient clinicopathologic features and survival. High expression of VEGF-C was identified in 40 (54.
View Article and Find Full Text PDFThe variability of neuronal firing has been an intense topic of study for many years. From a modelling perspective it has often been studied in conductance based spiking models with the use of additive or multiplicative noise terms to represent channel fluctuations or the stochastic nature of neurotransmitter release. Here we propose an alternative approach using a simple leaky integrate-and-fire model with a noisy threshold.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
July 2010
Thalamocortical (TC) neurones are known to express the low-voltage activated, inactivating Ca2+ current I(T). The triggering of this current underlies the generation of low threshold Ca2+ potentials that may evoke single or bursts of action potentials. Moreover, this current can contribute to an intrinsic slow (<1 Hz) oscillation whose rhythm is partly determined by the steady state component of I(T) and its interaction with a leak current.
View Article and Find Full Text PDFBackground: Hematopoietic growth factors (HGFs), such as macrophage-colony stimulating factor (M-CSF) are produced aberrantly in many malignancies. Esophageal cancer (EC) is characterized by late diagnosis, rapid progression and poor survival. The purpose of the present study was to determine the clinical usefulness of M-CSF in the diagnosis of EC and its histological type - squamous cell cancer of the esophagus (ESCC).
View Article and Find Full Text PDFEur J Cardiothorac Surg
September 2010
Objective: Lymph node metastasis is a characteristic of malignant cancers and is observed more frequently in oesophageal cancer than in other digestive tract cancers, making it one of the most important prognostic factors. Vascular endothelial growth factors C (VEGF-C) and D (VEGF-D) are important lymphangiogenic factors in human cancers and lymphangiogenesis is associated with lymph node metastasis. The aim of the study was to determine the correlation between pre-treatment serum levels of VEGF-C (sVEGF-C) and VEGF-D (sVEGF-D) and clinicopathologic features in patients with oesophageal cancer.
View Article and Find Full Text PDFWe report evidence of mode-locking to the envelope of a periodic stimulus in chopper units of the ventral cochlear nucleus (VCN). Mode-locking is a generalized description of how responses in periodically forced nonlinear systems can be closely linked to the input envelope, while showing temporal patterns of higher order than seen during pure phase-locking. Re-analyzing a previously unpublished dataset in response to amplitude modulated tones, we find that of 55% of cells (6/11) demonstrated stochastic mode-locking in response to sinusoidally amplitude modulated (SAM) pure tones at 50% modulation depth.
View Article and Find Full Text PDFIntroduction: Matrix metalloproteinase 9 (MMP-9) is a proteolytic enzyme which is associated with tumor progression including invasion, migration, angiogenesis, and metastasis due to its ability to degrade type IV collagen.
Objectives: The aim of the study was to assess clinical significance of MMP-9 measurement in the diagnostic evaluation of patients with esophageal squamous cell carcinoma (ESCC).
Patients And Methods: The study included 63 patients with ESCC and 30 healthy subjects.
We investigate retrospectively the efficacy of self-expandable metallic stents (SEMS) for severe respiratory distress (SRD) in patients with central airway obstruction (CAO). Thirty three patients with CAO were treated with SEMS using fiberoptic bronchoscopy method. We found an intraluminal obstruction present in 7, extraluminal compression in 10, and combined stenosis in 16 cases.
View Article and Find Full Text PDFVarious alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) exist in the human esophageal mucosa. In our last experiments we have shown that ADH and ALDH are present also in the esophageal cancer cells. Moreover, the activities of total ADH and class IV isoenzymes were significantly higher in cancer tissue than in healthy mucosa, which suggests that these changes may be reflected by enzyme activity in the serum.
View Article and Find Full Text PDFMetalloproteinase-9 (MMP-9) is the proteolytic enzyme degrading type IV collagen, and plays important role in the invasiveness and metastatic potential of tumor cells. The aim of the current study was to compare the association between the intensity of MMP-9 expression in neoplastic cells and in the interstitial inflammatory infiltrate cells in esophageal cancer with clinicopathological features of esophageal cancer (EC) and in different histopatological types of EC, e.g.
View Article and Find Full Text PDFBackground And Purpose: The endocannabinoid virodhamine is a partial agonist at the cannabinoid CB(1) receptor and a full agonist at the CB(2) receptor, and relaxes rat mesenteric arteries through endothelial cannabinoid receptors. Its concentration in the periphery exceeds that of the endocannabinoid anandamide. Here, we examined the influence of virodhamine on the human pulmonary artery.
View Article and Find Full Text PDFBackground/aims: Ethanol consumption is associated with an increased risk of esophageal cancer. The carcinogenic compound is acetaldehyde, the product of ethanol metabolism. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) are the main enzymes involved in ethanol metabolism, which leads to generation of acetaldehyde.
View Article and Find Full Text PDFLung cancer is the leading cause of death worldwide. High mortality comes out mainly of the fact that majority of the cases are diagnosed in advanced stadium. An expanded diagnostics of precancerous conditions would certainly contribute to lowering the mortality rate.
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