30 research outputs found
Numerical Tests-Based Assessment of the Procedures of Blurry and Noisy Image Enhancement
An extension of the test-based method of multi-aspect numerical assessment of the quality of image enhancement procedures on blurry and noisy images is presented. The principles of construction of the tests affected by various types and intensity of blurring and noising are described. Linear models of blurring have been defined. Formal definitions of measurable parameters characterizing the quality of image enhancement procedures are proposed. Comments on the errors and applicability limitations of the proposed testing method are also given. In a numerical experiment, the utility of the method by comparative assessment of 18 various image enhancement procedures is proven. Remarks concerning the properties of several widely-known image enhancement procedures are formulated. Concluding remarks about the utility of the presented method of image enhancement procedures assessment are given
The feasibility and efficacy of secondary neck dissections in thyroid cancer metastases
The purpose of the study was to assess the feasibility of secondary neck dissections (ND) in different types of thyroid cancer (TC), to evaluate the influence of ND extent on morbidity and to describe biochemical and clinical outcomes. 51 patients previously operated for TC (33-well differentiated TC-WDTC, 15 medullary TC-MTC, 3 poorly differentiated TC-PDTC) presenting detectable nodal disease. Reoperations covered I–VII neck levels. Radical neck dissection was performed in 22 patients, selective neck dissection in 29 patients. 14 central compartment (CC), 10 mediastinal and 41 level IV excisions were performed. Postoperative complications occurred in 13 patients: 4 chyle leaks, 3 massive bleedings, 8 permanent vocal cord pareses, hypoparathyroidism in 22 patients (43.1 %), 2 patients expired in perioperative period. In WDTC: in seven patients thyroglobulin level normalized directly after ND, in ten patients in the follow-up; six patients developed distant metastases. None of the patients with MTC achieved calcitonin level <10 pg/ml; nine patients developed distant metastases. None of the patients with PDTC achieved Tg <2 mg/ml; two patients died, the third developed distant metastases. Secondary ND in TC present a challenge by means of surgical approach and possibility of complications. In MTC and PDTC the long-term results were unsatisfactory. In WDTC, the secondary ND should be performed due to strong indications. Metastases localization in levels IV, VI, VII were connected with high complication rate, but these surgeries were crucial for satisfactory oncological outcomes
Assessing Various Control Samples for Microarray Gene Expression Profiling of Laryngeal Squamous Cell Carcinoma
Selection of optimal control samples is crucial in expression profiling tumor samples. To address this issue, we performed microarray expression profiling of control samples routinely used in head and neck squamous cell carcinoma studies: human bronchial and tracheal epithelial cells, squamous cells obtained by laser uvulopalatoplasty and tumor surgical margins. We compared the results using multidimensional scaling and hierarchical clustering versus tumor samples and laryngeal squamous cell carcinoma cell lines. A general observation from our study is that the analyzed cohorts separated according to two dominant factors: "malignancy", which separated controls from malignant samples and "cell culture-microenvironment" which reflected the differences between cultured and non-cultured samples. In conclusion, we advocate the use of cultured epithelial cells as controls for gene expression profiling of cancer cell lines. In contrast, comparisons of gene expression profiles of cancer cell lines versus surgical margin controls should be treated with caution, whereas fresh frozen surgical margins seem to be appropriate for gene expression profiling of tumor samples.</p
Single nucleotide polymorphism rs11614913 associated with CC genotype in miR-196a2 is overrepresented in laryngeal squamous cell carcinoma, but not salivary gland tumors in Polish population
The miRNA-196a2 has shown significance in the development of various neoplasms, including head and neck squamous cell carcinoma (HNSCC). The oncogenic functionality of this miRNA is mediated via its potential to target annexin A1 mRNA, a tumor suppressor gene involved in inhibition of the NF-kappa B pathway. Interestingly, recent data indicate a susceptibility for aforementioned neoplasms in patients with the CC genotype vs the CT and TT genotypes of the rs11614913 SNP located within the DNA sequence of the miR-196a2 that results in elevated expression of the gene. To further investigate this phenomenon, we genotyped this SNP in 40 patients with laryngeal squamous cell carcinoma (LSCC), the most common tumor of the head and neck region and 60 patients with salivary gland tumors (SGT) that show a yet unexplained incidence increase in the last two decades. In agreement with previous reports, we have identified a statistically significant (p < 0.05) overrepresentation of the CC genotype in LSCC patients and demonstrated in LSCC cell lines that it results in elevated expression of miR-196a2 as compared to cell lines with the TT genotype of the respective SNP. Importantly, none of these correlations was found in patients with SGT. These findings underline the importance of the SNP rs11614913 for LSCC development in the Polish population and moreover highlight the different genetic background of the two studied neoplasms of the head and neck region
Loss of the MAF Transcription Factor in Laryngeal Squamous Cell Carcinoma
MAF is a transcription factor that may act either as a tumor suppressor or as an oncogene, depending on cell type. We have shown previously that the overexpressed miR-1290 influences MAF protein levels in LSCC (laryngeal squamous cell carcinoma) cell lines. In this study, we shed further light on the interaction between miR-1290 and MAF, as well as on cellular MAF protein localization in LSCC. We confirmed the direct interaction between miR-1290 and MAF 3'UTR by a dual-luciferase reporter assay. In addition, we used immunohistochemistry staining to analyze MAF protein distribution and observed loss of MAF nuclear expression in 58% LSCC samples, of which 10% showed complete absence of MAF, compared to nuclear and cytoplasmatic expression in 100% normal mucosa. Using TCGA data, bisulfite pyrosequencing and CNV analysis, we excluded the possibility that loss-of-function mutations, promoter region DNA methylation or CNV are responsible for MAF loss in LSCC. Finally, we identified genes involved in the regulation of apoptosis harboring the MAF binding motif in their promoter region by applied FIMO and DAVID GO analysis. Our results highlight the role of miR-1290 in suppressing MAF expression in LSCC. Furthermore, MAF loss or mislocalization in FFPE LSCC tumor samples might suggest that MAF acts as a LSCC tumor suppressor by regulating apoptosis.</p
Gating of aquaporins by heavy metals in Allium cepa L. epidermal cells
Changes in the water permeability, aquaporin (AQP) activity, of leaf cells were investigated in response to different heavy metals (Zn2+, Pb2+, Cd2+, Hg2+). The cell pressure probe experiments were performed on onion epidermal cells as a model system. Heavy metal solutions at different concentrations (0.05 μM–2 mM) were used in our experiments. We showed that the investigated metal ions can be arranged in order of decreasing toxicity (expressed as a decrease in water permeability) as follows: Hg>Cd>Pb>Zn. Our results showed that β-mercaptoethanol treatment (10 mM solution) partially reverses the effect of AQP gating. The magnitude of this reverse differed depending on the metal and its concentration. The time course studies of the process showed that the gating of AQPs occurred within the first 10 min after the application of a metal. We also showed that after 20–40 min from the onset of metal treatment, the water flow through AQPs stabilized and remained constant. We observed that irrespective of the metal applied, the effect of AQP gating can be recorded within the first 10 min after the administration of metal ions. More generally, our results indicate that the toxic effects of investigated metal ions on the cellular level may involve AQP gating
Transmission and clearance of human papillomavirus infection in the oral cavity and its role in oropharyngeal carcinoma - A review
The majority of sexually active individuals becomes infected with human papillomavirus (HPV) at least once in their lifetime. Pathways for HPV transmission vary across different mucosal sites per individual. They include autoinoculation within one host, direct transmission between individuals (including perinatal transmission and transmission during sexual activity), and indirect transmission through contact with hands. The authors aim to clarify the prevalence and route of transmission per anatomic site, inter- and intra-individually, using a narrative review of the literature. In conclusion, transmission of HPV to the oral cavity and oropharynx is hypothesised to occur mainly through sexual contact. Transmission of particles through saliva has not been proven and daily living activities are not a documented source of HPV infection. Oropharyngeal HPV related cancer survivors and their partners do not show increased risk of infection during sexual intercourse. Transmission of HPV to the oral cavity (autoinoculation with fingers or transmission through saliva in deep kissing) is probably of limited importance
Oral-genital human papillomavirus infection in Polish couples: frequent detection of HPV 42
Abstract Background Human papillomavirus (HPV) contributes to the development of cervical and oropharyngeal tumors. The increased incidence of HPV associated oropharyngeal tumors is lately being observed also in Polish population. The worldwide distribution of HPV varies and the studies rarely combine analysis of virus genotypes in both: genital and oropharyngeal locations. Therefore, in our study, we investigated HPV distribution in both anatomical sites of females with previous history of cervical cancer or with pre-cancerous lesion and their partners to establish the dominant types in Polish couples in genital and oropharyngeal areas, as they can be easily sexually transmitted. Methods The study group consisted of 197 females and their partners. Each female had current or previous cervical pathology and HPV detected in gynecological swab with the use of Anyplex™ II HPV28 Detection system. This system is based on multiplexed real time PCR and enables detection of 19 high-risk and 9 low-risk HPVs. Results Beside women, the virus was found in 114/197 of men in their foreskin swabs. Additionally, HPV was detected in oropharyngeal swabs of 39/197 female and 56/197 male participants. HPV 16/31/42/39/54 dominated in female and HPV 66/42/16/31/53 in male genital locations. The incidence of HPV in oropharynx was lower, top five genotypes included: HPV 6/39/42/35/16 in women compared to HPV 39/6/42/40/33 in men. HPV16 was the most frequently detected virus type, found in 70/197 examined cervical swabs. It was significantly more prevalent as single infection in females, previously treated for the cervical cancer (p = 0.035). Moreover, regular presence of low risk type 42 was noticeable in both sexes, in both kind of swabs. There was a trend observed towards its prevalence as single infectious agent in women with previous history of cervical cancer (p = 0.069). Conclusions Our results showed the distribution of HPV genotypes in Polish couples, in which each woman is HPV positive, indicating a common infection of HPV 42, regardless of sex and anatomical site. These findings shed new light on HPV 42 significance, however they should be verified on a larger group of Polish participants, followed regularly in 6 months intervals, in oral as well as in genital areas
Assessing Various Control Samples for Microarray Gene Expression Profiling of Laryngeal Squamous Cell Carcinoma
Selection of optimal control samples is crucial in expression profiling tumor samples. To address this issue, we performed microarray expression profiling of control samples routinely used in head and neck squamous cell carcinoma studies: human bronchial and tracheal epithelial cells, squamous cells obtained by laser uvulopalatoplasty and tumor surgical margins. We compared the results using multidimensional scaling and hierarchical clustering versus tumor samples and laryngeal squamous cell carcinoma cell lines. A general observation from our study is that the analyzed cohorts separated according to two dominant factors: “malignancy”, which separated controls from malignant samples and “cell culture-microenvironment” which reflected the differences between cultured and non-cultured samples. In conclusion, we advocate the use of cultured epithelial cells as controls for gene expression profiling of cancer cell lines. In contrast, comparisons of gene expression profiles of cancer cell lines versus surgical margin controls should be treated with caution, whereas fresh frozen surgical margins seem to be appropriate for gene expression profiling of tumor samples