scholarly journals The determination of thorium in high grade and low grade ores

10.3133/tei44 ◽  
1947 ◽  
Keyword(s):  
Low Grade ◽  
High Grade

Determination of expression of platelet derived growth factor receptors (PDGFR) in astrocitic tumors

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 11518-11518 ◽  
Author(s):  
C. H. Barrios ◽  
F. S. Viola ◽  
L. M. Coutinho ◽  
E. Paglioli
Keyword(s):  
Tumor Vasculature ◽  
Molecular Target ◽  
Platelet Derived Growth Factor ◽  
Low Grade ◽  
High Grade ◽  
Santa Cruz ◽  
Cell Compartment ◽  
Oncology Unit

11518 Background: PDGF and its receptors (α and β) are frequently expressed together in gliomas raising the possibility that an autocrine/paracrine loop could contribute to the pathogenesis of these tumors. Studies with immunohistochemistry (IHC) and in situ hybridization have clarified that PDGF-α receptors (PDGF-R α) are preferentially expressed in tumor cells, whereas PDGF-β receptors (PDGF-R β) are preferentially expressed in proliferating endotelial cells within the tumor vasculature. Objective: Determine the expression of PDGF-R α and β in astrocitic tumors. Methods: Paraffin blocks samples from patients with a diagnosis of low-grade astrocitoma, anaplastic astrocitoma, and glioblastoma were obtained from the Neuro-Oncology Unit at Hospital São Lucas-PUCRS. These patients presented and were treated from 1996 through 2001. We collected a total of 130 cases: 57 Low-grade astrocitomas (LGA), 13 Anaplastic Astrocitomas (AA), and 60 Glioblastomas (GBM). All cases were studied with standard IHC techniques using antibodies for PDGFR α and β (Santa Cruz Biotechnology). Results: See table . Conclusion: The expression of PDGF-R α and β in low-grade tumors reflects the possible role these receptors may have in the evolution of these neoplasms. More importantly we documented that over 60% of high-grade gliomas (61% in AA; 65% in GBM) show expression of PDGF-R β predominantly in the endothelial cell compartment of the tumors. This is consistent with and reflects the extensive angiogenesis observed in these diseases. The level of expression we encountered identifies an attractive molecular target to explore. [Table: see text] No significant financial relationships to disclose.

scholarly journals Determination of human papillomavirus 16 physical status through E1/E6 and E2/E6 ratio analysis

2014 ◽  
Vol 63 (12) ◽  
pp. 1716-1723 ◽  
Author(s):  
Dimitris Tsakogiannis ◽  
Zaharoula Kyriakopoulou ◽  
Irina Georgia Anna Ruether ◽  
Grigoris D. Amoutzias ◽  
Tilemachos G. Dimitriou ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
Present Report ◽  
Target Selection ◽  
Low Grade ◽  
High Grade ◽  
Physical Status ◽  
Major Step ◽  
Significant Information ◽  
Host Chromosome

Human papillomavirus (HPV) 16 genome integration into the host chromosome is a crucial event during the life cycle of the virus and a major step towards carcinogenesis. The integration of HPV16 DNA promotes a constitutive high expression level of E6 and E7 oncoproteins, resulting in the extensive proliferation of the infected epithelial cells. In the present report the physical status of the HPV16 genome was studied, through determination of E1/E6 and E2/E6 DNA copy number ratios in 61 cervical samples of low- and high-grade malignancy and 8 cervical cancer samples, all of them associated with HPV16 infection. The selection of E1, E2 and E6 amplification target regions was performed according to the most prevalent deleted/disrupted sites of E1 and E2 genes. For this target selection we also considered the most conserved regions of E1, E2 and E6 genes among the same HPV16 isolates that were recently reported by our group. The analysis of HPV16 DNA form revealed a significant association among the mixed DNA forms in low-grade and high-grade malignancies, (χ2, P<0.01). The comparative analysis of E1/E6 and E2/E6 in the same cervical samples provides an accurate picture of HPV16 DNA form and may reveal whether different HPV16 DNA integrants coexist in the same cervical sample or not. This study proposes that E1/E6 and E2/E6 ratios determine with accuracy the HPV16 DNA integration pattern and may predict multiple integration events in the examined sample, thus providing significant information about the progression of cervical dysplasia.

Patterns in the care of oligodendrogliomas and oligoastrocytomas: A single center experience

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e13034-e13034
Author(s):  
S. H. Kizilbash ◽  
L. Nadeau
Keyword(s):  
Radiation Therapy ◽  
Surgical Resection ◽  
Progression Free Survival ◽  
Low Grade ◽  
High Grade ◽  
Single Center Experience ◽  
Data Collection And Analysis ◽  
Unique Identity

e13034 Background: Although rare, oligodendrogliomas (ODs) and oligoastrocytomas (OAs) have established a unique identity due to their sensitivity to chemotherapy, especially if they exhibit combined loss of heterozygosity (LOH) of 1p and 19q. However, optimal management is still controversial and data is lacking on actual practice patterns. This study describes the epidemiology of ODs/OAs at a community based hospital in Michigan and evaluates the management of these tumors, especially with respect to 1p/19q LOH. Methods: A retrospective review was conducted of all cases of OD and OA that were managed at our institution from 1975 to 2007. 135 patients were isolated. Of these, 48 patients had already been evaluated for 1p/19q LOH. This latter subset underwent data collection and analysis. Results: 31 patients had low-grade tumors (either ODs or OAs) while 17 had high grade tumors (anaplastic ODs or anaplastic OAs). Of the low grade tumors, 35% had combined 1p/19q LOH. 71% underwent surgical resection, 35% received chemotherapy, and 26% received radiation therapy. As for the high grade tumors, 47% had combined 1p/19q LOH. 88% underwent surgical resection, 76% received chemotherapy, and 59% received radiation therapy. At a mean of 29 months of follow up, eight patients had tumor progression while 12 died. Median progression free survival (MPFS) for patients receiving chemotherapy was increased in patients with combined 1p/19q LOH, for both low-grade tumors (34 vs. 20 months) and high-grade tumors (14 vs. 8 months). Also, significantly more patients with low-grade tumors and combined 1p/19q LOH were offered chemotherapy when compared to those without 1p/19q LOH (64% vs 20%, p = 0.04, Fisher exact). However, in patients with high-grade tumors, knowledge of 1p/19q LOH did not significantly impact the choice to administer chemotherapy (88% vs. 67%, p = 0.67). Conclusions: Patients with ODs/OAs and combined 1p/19q LOH who have been treated with chemotherapy demonstrate increased MPFS when compared with those without this genotype. Despite this, determination of 1p/19q LOH significantly affects physician choice to offer chemotherapy only in patients with low-grade tumors, but not in those with high-grade tumors. A future study is in development to determine 1p/19q LOH status for the remaining 87 patients. No significant financial relationships to disclose.

scholarly journals Determination of Gold Particle Characteristics for Sampling Protocol Optimisation

Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1109
Author(s):  
Simon C. Dominy ◽  
Ian M. Platten ◽  
Hylke J. Glass ◽  
Saranchimeg Purevgerel ◽  
Brian W. Cuffley
Keyword(s):  
Particle Size ◽  
Gold Particle ◽  
Low Grade ◽  
Large Sample Size ◽  
High Grade ◽  
Sampling Protocol ◽  
Gold Particles ◽  
Sampling Protocols ◽  
Very High

Sampling, sample preparation, and assay protocols aim to achieve an acceptable estimation variance, as expressed by a relatively low nugget variance compared to the sill of the variogram. With gold ore, the typical heterogeneity and low grade generally indicate that a large sample size is required, and the effectiveness of the sampling protocol merits attention. While sampling protocols can be optimised using the Theory of Sampling, this requires determination of the liberation diameter (dℓAu) of gold, which is linked to the size of the gold particles present. In practice, the liberation diameter of gold is often represented by the most influential particle size fraction, which is the coarsest size. It is important to understand the occurrence of gold particle clustering and the proportion of coarse versus fine gold. This paper presents a case study from the former high-grade Crystal Hill mine, Australia. Visible gold-bearing laminated quartz vein (LV) ore was scanned using X-ray computed micro-tomography (XCT). Gold particle size and its distribution in the context of liberation diameter and clustering was investigated. A combined mineralogical and metallurgical test programme identified a liberation diameter value of 850 µm for run of mine (ROM) ore. XCT data were integrated with field observations to define gold particle clusters, which ranged from 3–5 mm equivalent spherical diameter in ROM ore to >10 mm for very high-grade ore. For ROM ore with clusters of gold particles, a representative sample mass is estimated to be 45 kg. For very-high grade ore, this rises to 500 kg or more. An optimised grade control sampling protocol is recommended based on 11 kg panel samples taken proportionally across 0.7 m of LV, which provides 44 kg across four mine faces. An assay protocol using the PhotonAssay technique is recommended.

Klinische Wertigkeit der Positronen-Emissions-Tomographie (PET) bei onkologischen Fragestellungen: Ergebnisse einer interdisziplinären Konsensuskonferenz

1996 ◽  
Vol 35 (02) ◽  
pp. 42-52 ◽  
Author(s):  
R. Bares ◽  
U. Bull ◽  
A. Guhlmann ◽  
E. Moser ◽  
M. F. Wannenmacher ◽  
...  
Keyword(s):  
Low Grade ◽  
High Grade ◽  
Klinische Anwendung ◽  
Wissenschaftliche Studien

Zusammenfassung Ziel: Es ist das Ziel der vorliegenden Arbeit, an Hand bisher publizierter Studienergebnisse eine Beurteilung des klinischen Stellenwertes von PET in der Onkologie zu erarbeiten. Methoden: Im Rahmen einer interdisziplinären Konferenz mit namhaften Experten wurde eine Wertung des gegenwärtigen Stands von PET in der Onkologie an Hand der in der Literatur dokumentierten Studienergebnisse erarbeitet. Angestrebt wurde eine differenzierte Bewertung von PET für die klinische Anwendung in fünf Klassen (1a, 1b, 2a, 2b, 3) von »angemessen« (1a), »akzeptabel« (1b), »hilfreich« (2a), »noch keine Bewertung möglich« (2b), »ohne Nutzen« (3). Ergebnisse: Für den klinischen Einsatz in der Onkologie ist 2-F18-Fluorodeoxyglukose (FDG) das Radiopharmakon der Wahl. PET ist klinisch in der Patientenversorgung zur Rezidivdiagnostik von high-grade Gliomen (FDG), low-grade Gliomen (C-11 Methionin oder F-18 Tyrosin), für die Dignitätsdiagnostik des peripheren Lungenrundherdes bei Risikopatienten sowie für die Diagnostik des Pankreaskarzioms indiziert (Indikation 1a). PET kann in der Patientenversorgung bei folgenden Indikationen (1b) eingesetzt werden: »low-grade« Gliome, Suche nach unbekanntem Primärtumor bei Kopf-Hals-Tumoren, Rezidivdiagnostik des nicht kleinzelligen Bronchialkarzinoms sowie des Rektumkarzinoms, Lymphknotenstaging beim nicht kleinzelligen Bronchial-Karzinom, Pan-kreas-Karzinom, muskelinvasiven Blasen-Karzinom und Hoden-Karzinom. Staging bei M. Hodgkin (Stad. I/II versus III), frühe Therapiekontrolle bei Resttumor und Rezidivdiagnostik bei M. Hodgkin und hochmalignen Non-Hodgkin-Lymphomen, Lymphknoten-Staging und Fern-metastasensuche beim malignen Melanom (Breslow >1,5 mm), Lymphknoten- und Fernmetastasen-Nachweis beim Schilddrüsen-Karzinommit erhöhtem hTg und nicht radiojodspeichernden Metastasen. Zahlreiche weitere Indikationen zeichnen sich bereits jetzt ab, sind jedoch noch weniger gut durch wissenschaftliche Studien belegt. Für die meisten Indikationen außerhalb wissenschaftlicher Studien ist eine individuelle Kosten-Nutzen-Betrachtung durch den verantwortlichen Arzt geboten. Schlußfolgerungen: Die metabolische Bildgebung von PET besitzt für eine Vielzahl onkologischer Fragestellungen prinzipielle Vorteile gegenüber der anatomisch-morphologisch orientierten Schnittbilddiagnostik. Für die klinische Indikationsstellung ist allerdings eine differenzierte Betrachtung der spezifischen Leistungsfähigkeit von PET geboten.

CD133/CD166/Ki-67 Triple Immunouorescence Assessment for Putative Cancer Stem Cells in Colon Carcinoma*

2014 ◽  
Vol 23 (2) ◽  
pp. 161-170 ◽  
Author(s):  
Claudiu Margaritescu ◽  
Daniel Pirici ◽  
Irina Cherciu ◽  
Alexandru Barbalan ◽  
Tatiana Cârtâna ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Stem Cells ◽  
Colon Cancer ◽  
Cancer Stem Cells ◽  
Colon Carcinoma ◽  
Sodium Dodecyl ◽  
High Grade Dysplasia ◽  
Early Event ◽  
Low Grade ◽  
High Grade

Background & Aims: Colorectal cancer represents the third most common malignancy and the fourth most common cause of cancer death worldwide. The existence of drug-resistant colon cancer stem cells is thought to be one of the most important reasons behind treatment failure in colon cancer, their existence putatively leading to metastasis and recurrences. The aim of our study was to investigate the immunoexpression patterns of CD133 and CD166 in colon carcinoma, both individually and in combination, assessing their significance as prognostic markers.Methods. A total of 45 retrospective colon adenocarcinoma cases were investigated by enzymatic and multiple fluorescence immunohistochemistry for their CD133 and CD166 expression and colocalization.Results. Both CD133 and CD166 were expressed to different extents in all cancer specimens, with apredominant cytoplasmic pattern for CD133 and a more obvious membranous-like pattern for CD166.Overall, when comparing their reactivity for the tumoral tissue, CD166 expression areas seemed to be smaller than those of CD133. However, there was a direct correlation between CD133 and CD166 expression levels throughout the entire spectrum of lesions, with higher values for dysplastic lesions. Colocalization of CD133/ CD166 was obvious at the level of cells membranes, with higher coeficients in high grade dysplasia, followed by well and moderate differentiated tumours.Conclusions. CD133/CD166 colocalization is an early event occurring in colon tumorigenesis, with thehighest coeficients recorded for patients with high grade dysplasia, followed by well differentiated tumours. Thus, we consider that the coexpression of these two markers could be useful for further prognostic andtherapeutically stratification of patients with colon cancer.Abbreviations: AJCC - American Joint Committee on Cancer; CCD - charge-coupled device camera sensor; CD133 - prominin-1 (PROM1); CD166 - Activated Leukocyte Cell Adhesion Molecule (ALCAM); CRC - colorectal cancer; CSC - cancer stem cells; DAB - 3,3'-diaminobenzidine chromogen; DAPI - 4',6-diamidino- 2-phenylindole; HE - Hematoxylin and eosin staining; HGD - high grade dysplasia; HRP - horseradish peroxidase; LGD - low grade dysplasia; SDS - sodium dodecyl sulfate*Part of this work has been accepted as a poster presentation at the Digestive Disease Week (DDW) meeting, Chicago, IL, USA May 3-6, 2014

MOLECULAR AND GENETIC SUBTYPES OF OVARIAN CANCER: PROSPECTS FOR FURTHER STUDIES

2019 ◽  
Vol 65 (1) ◽  
pp. 56-62
Author(s):  
Alisa Villert ◽  
Larisa Kolomiets ◽  
Natalya Yunusova ◽  
Yevgeniya Fesik
Keyword(s):  
Ovarian Cancer ◽  
Ovarian Carcinoma ◽  
Molecular Subtypes ◽  
Survival Rates ◽  
Consensus Algorithm ◽  
Histopathological Diagnosis ◽  
Low Grade ◽  
High Grade ◽  
Ovarian Carcinomas ◽  
Genetic Subtypes

High-grade ovarian carcinoma is a histopathological diagnosis, however, at the molecular level, ovarian cancer represents a heterogeneous group of diseases. Studies aimed at identifying molecular genetic subtypes of ovarian cancer are conducted in order to find the answer to the question: can different molecular subgroups influence the choice of treatment? One of the achievements in this trend is the recognition of the dualistic model that categorizes various types of ovarian cancer into two groups designated high-grade (HG) and low-grade (LG) tumors. However, the tumor genome sequencing data suggest the existence of 6 ovarian carcinoma subtypes, including two LG and four HG subtypes. Subtype C1 exhibits a high stromal response and the lowest survival. Subtypes C2 and C4 demonstrate higher number of intratumoral CD3 + cells, lower stromal gene expression and better survival than sybtype C1. Subtype C5 (mesenchymal) is characterized by mesenchymal cells, over-expression of N-cadherin and P-cadherin, low expression of differentiation markers, and lower survival rates than C2 and C4. The use of a consensus algorithm to determine the subtype allows identification of only a minority of ovarian carcinomas (approximately 25%) therefore, the practical importance of this classification requires additional research. There is evidence that it makes sense to randomize tumors into groups with altered expression of angiogenic genes and groups with overexpression of the immune response genes, as in the angiogenic group there is a comparative superiority in terms of survival. The administration of bevacizumab in the angiogenic group improves survival, while the administration of bevacizumab in the immune group even worsens the outcome. Molecular subtypes with worse survival rates (proliferative and mesenchymal) also benefit most from bevacizumab treatment. This review focuses on some of the advances in understanding molecular, cellular, and genetic changes in ovarian carcinomas with the results achieved so far regarding the formulation of molecular subtypes of ovarian cancer, however further studies are needed.

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