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Abstract Background High fat diet impairs nitric oxide (NO) bioavailability, and induces insulin resistance. The link between NO availability and the metabolic adaptation to a high fat diet is not well characterized. The purpose of this study was to investigate the effect of high fat diet on metabolism in mice with decreased (eNOS-/-) and increased (DDAH overexpressed) NO bioavailability. Methods eNOS-/- (n = 16), DDAH (n = 24), and WT (n = 19) mice were fed a high fat diet (HFD) for 13 weeks. Body weight, biochemical parameters, adipokines and insulin were monitored. The matrigel in vivo model with CD31 immunostaining was used to assess angiogenesis. Gene expression in adipose tissues was analyzed by microarray and Real Time PCR. Comparisons of the mean values were made using the unpaired Student t test and p < 0.05 were considered statistically significant. Results eNOS-/- mice gained less weight than control WT and DDAH mice. In DDAH mice, a greater increase in serum adiponectin and a lesser increment in glucose level was observed. Fasting insulin and cholesterol levels remained unchanged. The angiogenic response was increased in DDAH mice. In adipose tissue of DDAH mice, genes characteristic of differentiated adipocytes were down-regulated, whereas in eNOS-/- mice, genes associated with adipogenesis, fatty acid and triglyceride synthesis were upregulated. Conclusions Our results indicate that increased NO availability attenuates some HFD induced alterations in metabolism and gene expression associated with insulin resistance.

Abstract Background The expression of metallothionein (MT) is involved in acquiring resistance to immune-mediated apoptosis; it is also a negative regulator of the immune response. Nasal polyps are typified by a resistance to immune-mediated apoptosis as well as by excessive immune cell infiltration. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a membrane protein capable of inducing the apoptosis of CTLs and NK cells. The aim of the present study has been to explore the expression of metallothionein with respect to immune cell presence and immune cell activity. In our study, we identified immune cells using CD4 and CD68 antigen expression and evaluated their activity using CD25 antigen expression. We then analyzed metallothionein, RCAS1, CD25, CD4, and CD68 in a sampling of 50 nasal polyps using the immunohistochemistry method. We were able to divide the nasal polyps into three main groups according to their predominant immune cell infiltration: eosinophilic nasal polyps (21 cases), lymphocytic nasal polyps (17 cases), and neutrophilic nasal polyps (12 cases). Results In the present study, statistically significant differences between the MT expression in the epithelium and that in the stroma of the nasal polyps along with the accompanying alterations in activation markers on immune cells were found and the number of macrophages in both the eosinophilic and the lymphocytic nasal polyps was assessed. RCAS1-expressing macrophages were found only in the eosinophilic nasal polyps. Conclusion MT expression seems to favor the survival of nasal polyp epithelial cells in the adjacent area of increasingly cytotoxic immune activity. RCAS1-expressing macrophages seem to participate in creating the immune suppressive microenvironment and so help to sustain local inflammation.

Abstract Background Obesity and its complications lead to vascular injury, atherosclerosis, diabetes and pathological angiogenesis. One of the models to study the obesity and its entanglements is the New Zealand Obese mice model. Aim of this study was to check the effect of high fat diet on changes in biochemical parameters as well as on process of angiogenesis in NZO mice. Methods NZO mice were fed with standard (ST) or high fat (HF) diet for seven weeks. Body weight and serum biochemical parameters were monitored. The PECAM1 positive vessel-like structures immunostaining, as well as the gene expression of the matrigel penetrating cells by microarray (confirmed by real-time PCR method) were analyzed. Results Mice fed with HF diet developed obesity. Number of newly created vessels with lumen was correlated with hyperglycemia and animal weight gain. The number of PECAM1 positive cells in matrigel tended to increase during HF diet. Microarray results revealed changes in gene expression (activation of the oxidative stress and insulin resistance, inhibition of apoptosis and cell differentiation), however without markers of endothelial cell network maturation. Conclusion Observed changes in the NZO mice on HF diet argue for the hyperglycemia related activation of angiogenesis, leading to the formation of pathological, immature network.

Abstract Background The purpose of this study has been to establish the level of RCAS1 – a membrane protein expressed in various cancer cells and able to induce apoptosis of CTLs and NK cells in pharyngeal and laryngeal cancer and its clear surgical margin – with respect to clinicopathological features and to patient's follow up and evaluate its possible role in cancer relapse. Methods A total of 122 tissue samples were obtained: 51 samples from laryngeal and pharyngeal squamous cell carcinoma, 51 samples from the clear surgical margins of these tumors, and 20 tissue samples derived from the healthy mucous membranes of the upper respiratory tract mucosa of patients without cancerous tumors. Patients were observed for a total of 4 years following surgical treatment. The level of RCAS1 expression was assessed by immunohistochemistry and Western blot. Results RCAS1 was identified in all laryngeal and pharyngeal carcinomas and in almost all the clear surgical margin samples. The level of RCAS1 expression was significantly higher in the cancerous samples than in the clear surgical margins and was determined to be related to the grade of the cancer and the presence of lymph node metastases. In cases of cancer relapse, significantly higher levels of RCAS1 expression were observed in the clear surgical margins. Conclusion Selective cytotoxic immune cell suppression concomitant with tumor growth and associated with RCAS1 expression seems to be an important event connected with cancer relapse.

Abstract Background Nasal polyp constitutes a benign growth process in the nasal and sinus mucosa. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a protein expressed mainly by various human cancer cells. It is not only the marker of cancer process and its expression can also be observed in physiological processes. It is responsible for the regulation of immune cells activity. DFF45 (DNA fragmenting factor) has been described as a substrate for caspase-3. DFF45 seems to play an important role in the onset of apoptotic process by acting probably through the regulation of DNA fragmentation. The aim of the study was to evaluate the ability of nasal polyps to regulate the cytotoxic immune response and to determine their resistance to apoptosis. Results The higher RCAS1 level was identified in lymphocytic nasal polyps, the medium one in eosinophilic while the lowest was identified in neutrophilic. DFF-45 expression was higher in eosinophilic than in neutrophilic and lymphocytic nasal polyps. Conclusion The changes in DFF-45 level in nasal polyps might indicate a different resistance to apoptosis mediated by immune cells. The alterations in RCAS1 expression indicate that nasal polyps have the ability to regulate the cytotoxic immune response. The breaking of resistance to immune mediated apoptosis in nasal polyps might have a new therapeutic impact.

Introduction: Diagnosis of sarcoidosis is based on clinical status and radiologic specific findings. Tissue confirmation of noncaseating granulomas is crucial. Pathological confirmation of pulmonary sarcoidosis is most commonly accomplished by bronchoscopy, which has a diagnostic yield of approximately 60%–70%. Objectives: In this prospective study, we analysed potential benefit of EBUS‐TBNA and EBB combination, application of cell blocks and smears with puncturing more than one station of lymph nodes in order to determine optimal strategy in diagnosis of sarcoidosis. Methods: About 133 patients with suspicion of sarcoidosis (stage I and stage II) were included in this study. Each patient underwent conventional bronchoscopy with endobronchial biopsy (EBB) followed by the EBUS and puncturing at least two different lymph node stations. Results: Positive cytopathological verification of sarcoidosis in our study was obtained in 123 patients (92.5%). EBUS‐TBNA was diagnostic in 116 patients (87.2%). EBB was positive in 26 patients (19.55%). Combination of EBUS‐TBNA and EBB statistically increased diagnostic yield of sarcoidosis to 92.5%. Sensitivity of EBUS‐TBNA with EBB was 93.9%, specificity 100%, PPV 100% and NPV 20%. Conclusions: Combining EBUS‐TBNA from at least two lymph node stations and EBB increased diagnostic yield of sarcoidosis. Such diagnostic strategy had almost 93% of diagnostic yield in stage I and stage II of sarcoidosis. Taking into account the safety of the whole procedure with endobronchial ultrasonography combined with conventional endoscopy with EBB and its cost effectiveness, TBLB can be intended to diagnose stage III or IV of pulmonary sarcoidosis. [ABSTRACT FROM AUTHOR]