Search results for "Staining"
showing 10 items of 449 documents
Demonstration of dihydro-orotate dehydrogenase inNeurospora crassa hyphae with a cytochemical procedure
1971
Dihydro-orotate dehydrogenase activity was demonstrated in the hyphae of the fungusNeurospora crassa by a cytochemical technique. The activity was slightly stronger in the hyphal tips thus demonstrating the more intense metabolic activity in these parts of the mycelium. Several control reactions showed that the staining reaction was specific.
Filipin labelling and intramembrane particles on the membranes of early and later autophagic vacuoles in Ehrlich ascites cells
1987
Cholesterol and intramembrane particle distribution on autophagic vacuole membranes was studied in Ehrlich ascites cells using filipin labelling and freeze-fracture electron microscopy. Unsaturated fatty acids were stained using imidazole-buffered osmium tetroxide. Autophagocytosis was induced with vinblastine, and early autophagic vacuoles were accumulated by lowering the ATP level in the cells with iodoacetate. Filipin labelling was observed in the limiting membranes of later, apparently hydrolase-containing autophagic vacuoles, whereas the most newly-formed, doublemembrane limited vacuoles were not labelled. The limiting membranes of late, residual body-type vacuoles either showed patchy…
“Super p53” Mice Display Retinal Astroglial Changes
2013
Tumour-suppressor genes, such as the p53 gene, produce proteins that inhibit cell division under adverse conditions, as in the case of DNA damage, radiation, hypoxia, or oxidative stress (OS). The p53 gene can arrest proliferation and trigger death by apoptosis subsequent to several factors. In astrocytes, p53 promotes cell-cycle arrest and is involved in oxidative stress-mediated astrocyte cell death. Increasingly, astrocytic p53 is proving fundamental in orchestrating neurodegenerative disease pathogenesis. In terms of ocular disease, p53 may play a role in hypoxia due to ischaemia and may be involved in the retinal response to oxidative stress (OS). We studied the influence of the p53 ge…
Psammous desmo-osteoblastoma
1987
Fibro-osteo-cemental lesions of the jaw bones are a heterogeneous group of diseases which present problems in classification. Psammous desmo-osteoblastoma is one of four newly proposed entities (Makek 1983) and has until now been characterized by its light microscopic, clinical and radiological features. On electron microscopy this tumour exhibits fibroblastic (preosteoblastic), osteoblastic and osteocytic cells and a globular mineralization unlike the mineralization of the psammoma bodies. Immunohistological investigations with anti-osteonectin, a bone specific protein linking mineral to collagen, showed positive intracellular staining in all tumour cells and extracellular staining in the …
Myofibroblasts and increased angiogenesis contribute to periapical cystic injury containment and repair
2019
Background Myofibroblasts (MF) and angiogenesis are important factors in the development and expansion of cystic lesions, where these cells secrete growth factors and proteases, stimulating angiogenesis, matrix deposition and cell migration, affecting the growth of these periapicopathies. The present study aimed to evaluate the immunohistochemical expression of CD34 and α-SMA in radicular cysts (RC) and residual radicular cysts (RRC), with the purpose of contributing to a better understanding of the expansion and progression of these periapical lesions. Material and Methods The present study os a descriptive, quantitative and comparative analysis of positive CD34 and α-SMA immunohistochemic…
Endoscopic surveillance in ulcerative colitis: smart biopsies do it better.
2007
Patients with ulcerative colitis (UC) have a significantly higher risk for the development of colitisassociated colorectal cancer. Endoscopic surveillance is recommended. The growth pattern of dysplastic tissue is often multifocal and flat. Thus, significant lesions might be overlooked. Multiple random biopsies are recommended, but cannot eliminate the possibility of missed cancers with severe consequences for the patient. Chromoendoscopy with methylene blue or indigo carmine can unmask flat lesions and may solve this problem. In addition, confocal laser endomicroscopy enables in vivo histology with subcellular resolution during ongoing colonoscopy and leads to highly selected mucosal biops…
Infarct Size Measurement by Triphenyltetrazolium Chloride StainingVersus In VivoInjection of Propidium Iodide
1997
Infarct size delineation by triphenyltetrazolium chloride (TTC) staining is dependent on sufficient reperfusion. We therefore evaluated the possibility of using propidium iodide (PI), a reagent conventionally used in flow cytometry to fluorescently stain dead cells, for infarct size analysis after short periods of reperfusion. Forty-five rabbits were subjected to either 15 min, 2 h or 4.5 h of coronary artery occlusion without reperfusion, or to 15 min, 30 min and 2 h of coronary artery occlusion followed by 30 min, 1 h and 3 h of reperfusion. Fifteen min before terminating the experiment, PI was injected into the left atrium. Patent blue violet was used to delineate the area at risk. Follo…
Histological and histochemical changes in the colon mucosa after ureterosigmoidostomy or colonic conduit.
1988
A study was made of 22 patients previously subjected to urinary diversion, 12 with ureterosigmoidostomy and 10 with colon conduit. The histological and histochemical examination of biopsies of intestinal mucosa near to and far from the ureteral orifices showed transformations with considerable inflammatory infiltration, variations in the composition of the acid mucins with a prevalence of sialomucins, lengthening and branching of the glandular crypts, and sometimes dysplasias of the epithelium. These structural modifications are typical of transitional mucosa. Transitional mucosa might reflect an aspecific reaction of the intestinal mucosa or alternatively it might signify a precancerous co…
Chromoendoscopy and Other Novel Imaging Techniques
2006
The newly developed high-resolution and magnification endoscopes offer features that allow more and new mucosal details to be seen. They are commonly used in conjunction with chromoendoscopy. The analysis of mucosal surface details is beginning to resemble histologic examination. More accurate recognition of small flat and depressed neoplastic lesions is possible. Endoscopic prediction of neoplastic and nonneoplastic tissue is possible by analysis of surface architecture of the mucosa, which influences the endoscopic management. For the diagnosis of flat adenomas, chromoendoscopy should be a part of the endoscopist's armamentarium. In inflammatory bowel disease, chromoendoscopy can be used …
Limitations of Immunohistochemistry in Diagnosis of a Primary Mucinous Carcinoma of the Skin and Its Metastasis
2020
We describe the case of a 67-year-old female patient who presented with an unclear swelling on the right supraclavicular neck, two years after resection of a mucinous carcinoma on the right mastoid. Two pathological reports from separate universities diagnosed the primary mastoid skin lesion as a metastatic adenocarcinoma. Strikingly, GATA binding protein 3 (GATA3) and mammaglobin, both immunomarkers found in breast cancer, were positive. An urgent search for the primary tumor most likely in the breast was commenced. However, as no other primary tumor could be detected at that time, a Primary Mucinous Carcinoma of the Skin (PMCS) was also debated. Two years later neck node enlargement was s…