Growth of mica porphyroblasts under low-grade metamorphism – A Taiwanese case using in-situ 40Ar/39Ar laser microprobe dating

2016 ◽  
Vol 92 ◽  
pp. 1-11 ◽  
Author(s):  
Chih-Tung Chen ◽  
Yu-Chang Chan ◽  
Ching-Hua Lo ◽  
Chia-Yu Lu
Keyword(s):  
Low Grade ◽  
Grade Metamorphism ◽  
Laser Microprobe

scholarly journals Intra-Cystic (In Situ) Mucoepidermoid Carcinoma: A Clinico-Pathological Study of 14 Cases

2020 ◽  
Vol 9 (4) ◽  
pp. 1157
Author(s):  
Saverio Capodiferro ◽  
Giuseppe Ingravallo ◽  
Luisa Limongelli ◽  
Mauro Mastropasqua ◽  
Angela Tempesta ◽  
...  
Keyword(s):  
Alcian Blue ◽  
Tumor Invasion ◽  
Conservative Surgery ◽  
Low Grade ◽  
Mucin Production ◽  
Cystic Component ◽  
Early Growth Phase ◽  
Hematoxylin Eosin

Aims: To report on the clinico-pathological features of a series of 14 intra-oral mucoepidermoid carcinomas showing exclusive intra-cystic growth. Materials and methods: All mucoepidermoid carcinomas diagnosed in the period 1990–2012 were retrieved; the original histological preparations were reviewed to confirm the diagnosis and from selected cases, showing exclusive intra-cystic neoplastic components, additional sections were cut at three subsequent 200 m intervals and stained with Hematoxylin–Eosin, PAS, Mucicarmine and Alcian Blue, to possibly identify tumor invasion of the adjacent tissues, which could have been overlooked in the original histological preparations. Additionally, pertinent findings collected from the clinical charts and follow-up data were analyzed. Results: We identified 14 intraoral mucoepidermoid carcinomas treated by conservative surgery and with a minimum follow up of five years. The neoplasms were located in the hard palate (nine cases), the soft palate (two), the cheek (two) and the retromolar trigone (one). In all instances, histological examination revealed the presence of a single cystic space, containing clusters of columnar, intermediate, epidermoid, clear and mucous-producing cells, the latter exhibiting distinct intra-cytoplasmic mucin production, as confirmed by PAS, Mucicarmine and Alcian Blue stains. The cysts were entirely circumscribed by fibrous connective tissue, and no solid areas or infiltrating tumor cell clusters were detected. Conservative surgical resection was performed in all cases, and no recurrences or nodal metastases were observed during follow up. Conclusions: Mucoepidermoid carcinomas showing prominent (>20%) intra-cystic proliferation currently are considered low-grade tumors. In addition, we also unveil the possibility that mucoepidermoid carcinomas, at least in their early growth phase, may display an exclusive intra-cystic component and might be considered as in situ carcinomas, unable to infiltrate adjacent tissues and metastasize.

scholarly journals Expression of Semaphorin 3A in Malignant and Normal Bladder Tissue: Immunohistochemistry Staining and Morphometric Evaluation

Biology ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 109
Author(s):  
Ilan Bejar ◽  
Jacob Rubinstein ◽  
Jacob Bejar ◽  
Edmond Sabo ◽  
Hilla K Sheffer ◽  
...  
Keyword(s):  
Urothelial Carcinoma ◽  
Carcinoma In Situ ◽  
Urothelial Cancer ◽  
Basal Layer ◽  
Low Grade ◽  
High Grade ◽  
Bladder Tissue ◽  
Normal Bladder ◽  
Normal Bladder Tissue

Introduction: Our previous studies showed elevated levels of Semaphorin3a (Sema3A) in the urine of patients with urothelial cancer compared to healthy patients. The aim of this study was to analyze the extent of Sema3A expression in normal and malignant urothelial tissue using immune-staining microscopic and morphometric analysis. Materials and Methods: Fifty-seven paraffin-embedded bladder samples were retrieved from our pathology archive and analyzed: 14 samples of normal urothelium, 21 samples containing low-grade urothelial carcinoma, 13 samples of patients with high-grade urothelial carcinoma, 7 samples containing muscle invasive urothelial carcinoma, and 2 samples with pure urothelial carcinoma in situ. All samples were immunostained with anti Sema3A antibodies. The area of tissue stained with Sema3A and its intensity were analyzed using computerized morphometry and compared between the samples’ groups. Results: In normal bladder tissue, very light Sema3A staining was demonstrated on the mucosal basal layer and completely disappeared on the apical layer. In low-grade tumor samples, cells in the basal layer of the mucosa were also lightly stained with Sema3A, but Seama3A expression intensified upon moving apically, reaching its highest level on apical cells exfoliating to the urine. In high grade urothelial tumors, Seama3A staining was intense in the entire thickness of the mucosa. In samples containing carcinoma in situ, staining intensity was high and homogenous in all the neoplastic cells. Conclusions: Sema3A may be serve as a potential non-invasive marker of urothelial cancer.

Low-grade metamorphism and accretion tectonics: Southern Uplands terrain, Scotland

1985 ◽  
Vol 49 (352) ◽  
pp. 335-344 ◽  
Author(s):  
A. E. S. Kemp ◽  
G. H. J. Oliver ◽  
J. R. Baldwin
Keyword(s):  
Subduction Zones ◽  
Structural Data ◽  
Low Grade ◽  
Structural Level ◽  
Concomitant Increase ◽  
Illite Crystallinity ◽  
Grade Metamorphism ◽  
Trench Slope ◽  
Reflectance Data ◽  
Trajectory Characteristic

AbstractPrevious studies of low-grade metamorphism in the Southern Uplands accretionary terrain indicated prehnite-pumpellyite facies/anchizone conditions developed throughout the area, except for local preservation of trench-slope sediments and an accreted seamount at zeolite facies/advanced diagenetic grade. New graptolite reflectance data are presented that show a general northward increase in temperature in the Southern Uplands. The results from two cross-strike traverses in the southern and central belts in contemporaneous sequences, using illite crystallinity, illite lateral spacing (bo) , and graptolite reflectance, indicate the development of systematic accretion-related low-grade metamorphism. Well-developed and constant anchizone conditions occur throughout the NE (Langholm) traverse, associated with common, F1 accretion-related folding and a regionally penetrative S1 cleavage. In the SW (Kirkcudbright) traverse, however, the youngest, last accreted packets are preserved at a transitional diagenetic stage and lack a penetrative S1 cleavage. Illite crystallinity, graptolite reflectance, and bo increase systematically northward through earlier accreted packets, reaching values of the NE traverse only at the northern end. The concomitant increase of bo with illite crystallinity suggests the relatively high P-low T trajectory characteristic of subduction zones. Integration of metamorphic and structural data relates increasing intensity of aceretion-related F1 folding, developmertt of S1 fabric, and onset of later fold phases to grade of metamorphism and structural level within the accretionary pile.

Neodymium and strontium isotopic dating of diagenesis and low-grade metamorphism of argillaceous sediments

1994 ◽  
Vol 58 (5) ◽  
pp. 1471-1481 ◽  
Author(s):  
Urs Schaltegger ◽  
Peter Stille ◽  
Naoual Rais ◽  
Alain Piqué ◽  
Norbert Clauer
Keyword(s):  
Low Grade ◽  
Isotopic Dating ◽  
Grade Metamorphism
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