Search results for "Pith"
showing 10 items of 1308 documents
Frequency of micronucleus in oral epithelial cells after exposure to mate-tea in healthy humans
2014
Objectives: The aim of this study was to evaluate the possibility of technique simplification for cytology slides in order to evaluate the frequency of micronuclei (FMic) and conduct a experiment looking to know the FMic of oral epithelial cells of healthy volunteers exposed to mate tea (Ilex paraguarariensis). Material and Methods: This is a laboratorial and nonrandomized trial (quasi-experiment), where the nonusers subjects were exposed to mate-tea, consumed in the traditional way, two drinks, two times a day for a single week. Two cytology of exfoliated epithelial cells were obtained before and after the mate tea exposition. Results: The sample was composed by 10 volunteers. The age rang…
Hypoxic macrophages impair autophagy in epithelial cells through Wnt1: relevance in IBD.
2014
A defective induction of epithelial autophagy may have a role in the pathogenesis of inflammatory bowel diseases. This process is regulated mainly by extracellular factors such as nutrients and growth factors and is highly induced by diverse situations of stress. We hypothesized that epithelial autophagy is regulated by the immune response that in turn is modulated by local hypoxia and inflammatory signals present in the inflamed mucosa. Our results reveal that HIF-1 alpha and Wnt1 were co-localized with CD68 in cells of the mucosa of IBD patients. We have observed increased protein levels of beta-catenin, phosphorylated mTOR, and p62 and decreased expression of LC3II in colonic epithelial …
An experimental model for the exposure of human ciliated cells to sulfur dioxide at different concentrations
1994
Mucociliary transport is an important nonimmunological defense mechanism of the respiratory tract. The aim of this study was to investigate the effect of sulfur dioxide (SO2) at different concentrations on ciliary beat frequency (CBF). Ciliated cells were obtained from 12 volunteers by nose brush. CBF was quantified using video-interference microscopy. The cells were placed on a polycarbonate membrane in contact with the surface of a reservoir filled with RPMI 1640 (bicarbonate buffered) or Ringer's (electrolyte) solution, allowing the cells to be supplied by capillarity. In an exposure chamber the cells were exposed for 30 min to SO2 2.5-12.5 ppm at 37 degrees C and 100% air humidity. SO2 …
Parotid sialosis: morphometrical analysis of the glandular parenchyme and stroma among diabetic and alcoholic patients
2009
J Oral Pathol Med (2010) 39: 10–15 Background: Among the agents that cause parotid sialosis, diabetes mellitus type 2 and chronic alcoholism are included. In this study, the morphometrical modifications in the diabetic parotid sialosis were determined to compare them with the histopathological characteristics of alcoholic parotid sialosis. Methods: Five parotid biopsy samples obtained from patients with diabetic sialosis, 12 samples from patients with alcoholic sialosis and seven from individuals without these pathologies (control group) were analyzed. A morphometrical study of parotid parenchyme and stroma, using a digital image analyzer attached to an optical microscope, was carried out…
O6-methylguanine-DNA methyltransferase activity in breast and brain tumors.
1995
The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) is a main determinant of resistance of tumor cells to the cytostatic activity of chemotherapeutic alkylating agents (methylating and chloroethylating nitrosoureas) and is effective in protecting normal cells against genotoxic and carcinogenic effects resulting from DNA alkylation. Therefore, the level of expression of MGMT is significant for the response of both the tumor and the non-target tissue following application of nitrosoureas in tumor therapy. To determine the expression of MGMT in tumor tissue, we have assayed MGMT activity in 68 breast carcinomas and 38 brain tumors. There was a wide variation of MGMT expression…
Poorly differentiated synovial sarcoma: A case report
2001
Poorly differentiated synovial sarcoma is a rare soft tissue tumor. We studied a case arising in the pleural cavity of a young subject, characterised by the presence of spindle cell, small cell, and large epithelioid cell areas. We performed stains for mucosubstances and analysed the expression of cytokeratins 5/6, 7, 8, 18, 19, CEA, CD34, Ber-Ep4 and calretinin to characterize the phenotype of this neoplasm. We furthermore assessed immunohistochemically the presence of p53, Bcl-2, Bax and caspase 3, four apoptotic markers, to evaluate a relationship between apoptotic activity and the behaviour of this tumor. Our findings showed a strong presence of calretinin, p53 and Bcl-2 in all three ar…
Evaluation of DNA ploidy and degree of DNA abnormality in benign and malignant melanocytic lesions of the skin using video imaging.
2000
BACKGROUND Making a morphologic distinction between benign and malignant melanocytic tumors of the skin is frequently difficult, especially because “gray zones” between these lesions often exist. DNA image cytometry as an adjuvant method for the diagnosis and prognostic prediction of premalignant lesions and malignant tumors of many other organs is already well established. The aim of this study was to determine whether DNA image cytometry is helpful in distinguishing benign from malignant melanocytic lesions and whether cytometry would give valid information with which to predict the prognoses associated with malignant melanomas. METHODS DNA image cytometry was performed on 127 benign and …
Basaloid squamous cell carcinoma of the esophagus: diagnosis and prognosis.
1997
BACKGROUND. Basaloid squamous cell carcinoma (BSCC) is a recently recognized, poorly differentiated variant of squamous cell carcinoma (SCC), which is located predominantly in the upper aerodigestive tract. METHODS. In this study, clinical and pathologic parameters of 17 BSCCs and 133 typical SCCs of the esophagus that underwent potentially curative resection (no distant metastases, no residual tumor) were compared. In addition, light microscopic, electron microscopic, and immunohistochemical features of BSCC were investigated, to determine whether this type of carcinoma could be differentiated from other poorly differentiated carcinomas of the esophagus. RESULTS. Light microscopic study sh…
Evaluation of inflammatory reactions and genotoxic effects after exposure of nasal respiratory epithelia to benzene.
2003
<i>Background:</i> The aim of this study was to identify inflammatory changes as well as genotoxic effects in cultivated human respiratory epithelial cells after in vitro exposure to benzene. <i>Methods:</i> Primary cell cultures of nasal respiratory mucosa were exposed to synthetic air enriched with 5,000 µg/m<sup>3</sup> of benzene at an air/liquid interface over 8 h and then to synthetic air only over the following 24 h. Controls were continuously exposed to synthetic air over 32 h. To detect inflammatory reactions, release of prostaglandin E<sub>2</sub> was quantified using a competitive enzyme immunoassay. The Comet Assay was used to quan…
Role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and antibodies neutralizing virus epithelial infection in the control of CMV infec…
2015
The role of cytomegalovirus (CMV)-specific polyfunctional CD8+ T-cells and that of antibodies neutralizing virus epithelial infection (AbNEI) in the control of CMV DNAemia were investigated in 39 CMV-seropositive allogeneic stem-cell transplant (Allo-SCT) recipients with (n = 24) or without (n = 15) CMV DNAemia. AbNEI levels were monitored prospectively by means of a neutralization assay employing retinal epithelial cells (ARPE-19) and the recombinant CMV strain BADrUL131-Y4. Quantification of CMV-specific polyfunctional CD8+ T-cells (expressing two or three of the following markers: IFN-γγ, TNF-α and CD107a) in whole blood was performed by flow cytometry for intracellular cytokine staining…