970 resultados para High-Grade Thorium


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Mode of access: Internet.

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A granodiorite from Akilia, southwest Greenland, previously suggested to date putative life-bearing rocks to greater than or equal to3.84 Ga, is re-investigated using whole-rock major and trace-element geochemistry, and detailed cathodoluminescence image-guided secondary ion mass spectrometer analyses of zircon U-Th-Pb and rare earth elements. Complex zircon internal structure reveals three episodes of zircon growth and/or recrystallization dated to c. 3.84 Ga, 3.62 Ga and 2.71 Ga. Rare earth element abundances imply a significant role for garnet in zircon generation at 3.62 Ga and 2.71 Ga. The 3.62 Ga event is interpreted as partial melting of a c. 3.84 Ga grey gneiss precursor at granulite facies with residual garnet. Migration of this 3.62 Ga magma (or melt-crystal mush) away from the melt source places a maximum age limit on any intrusive relationship. These early Archaean relationships have been complicated further by isotopic reworking in the 2.71 Ga event, which could have included a further episode of partial melting. This study highlights a general problem associated with dating thin gneissic veins in polyphase metamorphic terranes, where field relationships may be ambiguous and zircon inheritance can be expected.

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This study evaluated the detection of human papillomavirus (HPV) 16 antibody in HPV 16-associated cervical intraepithelial neoplasia (CIN) in Australian women. Seroreactivity to HPV 16 L1 virus-like particles was assessed in patients with CIN 2 (n = 169) and CIN 3 (n = 229) lesions previously tested for the presence of HPV DNA. Seropositivity was significantly commoner in women with HPV 16 DNA-positive lesions (98/184) than in women with no HPV DNA in the lesion (15/47) or with HPV of types other than 16 in the lesion (43/167) (P = 0.0004). In addition, seropositivity was observed in 33% (55/169) of women with CIN 2 and 46% (106/229) of women with CIN 3, in keeping with the lower fraction of CIN 2 (57/169) than CIN 3 (127/229) biopsies positive for HPV 16 DNA. HPV 16 seropositivity is most common in women with HPV 16-associated CIN, but many patients with HPV-associated CIN 3 are seronegative, and HPV 16 seropositivity is common in women with CIN associated with other HPV types. Overall, HPV 16 serology is a poor predictor of presence of HPV 16-associated CIN 3 in patient population studied.

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We describe a tool for analysing information flow in security hardware. It identifies both sub-circuits critical to the preservation of security as well as the potential for information flow due to hardware failure. The tool allows for the composition of both logical and physical views of circuit designs. An example based on a cryptographic device is provided.

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Background/Aim: Heparanase (HPA) contributes to breast cancer metastasis by facilitating the breakdown of the basement membrane and extracellular matrix. High expression of HPA is thought to be associated with increased nodal involvement and poor survival in patients with breast cancer. Overexpression of cyclooxygenase-2 (COX-2) in breast cancer is associated with indicators of poor prognosis such as lymph node metastasis, poor differentiation, and large tumor size. The underlying mechanism by which HPA and COX-2 overexpression increases the metastatic potential of breast cancer is not fully-understood. To enhance our understanding over these mechanisms, we aimed to investigate the relationship between the size of the tumor and HPA expression, tumor grade as well as lymph node status in patients with breast cancer. Materials and Methods: Immunohistochemical analysis of HPA and COX-2 expression was performed on 246 breast tumor samples. The expression of HPA was correlated with COX-2 expression, tumor grade, lymph node status, oestrogen receptor status. Results: The overexpression of HPA and COX-2 was associated with increased likelihood of lymph node positivity in large, high-grade tumors. High-grade tumors with size greater than 20 mm, that overexpressed HPA, were 4-times more likely to be associated with lymph node involvement (OR 4.71, CI 1.21-18.25). Whereas, tumors greater than 20 mm in size were 5-times more likely to metastasize to the regional lymph nodes, if associated with overexpression of COX-2 (OR 5.5, CI 1.2-24.8). Conclusion: Expression of HPA appears to be a key mechanism by which large, highgrade breast tumors metastasize to regional lymph nodes, while COX-2 overexpression may be an independent predictor of lymph node positivity.

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Samples of high grade metamorphic basement rocks of Wilson Terrane cropping out in the Deep Freeze Range and on Kay Island were collected during GANOVEX VI to study their isotopic evolution. The age and origin of granulite facies gneisses and of their migmatite host rocks are especially of interest for the interpretation of the geological and tectonic development of North Victoria Land. Another important research aspect is the influence of the polyphase metamorphic evolution on the isotopic systems of whole rocks and minerals like zircon, garnet, orthopyroxene, amphibole and feldspar.

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High-grade serous ovarian cancer (HGSC) is the most prevalent epithelial ovarian cancer characterized by late detection, metastasis and resistance to chemotherapy. Previous studies on the tumour immune microenvironment in HGSC identified STAT1 and CXCL10 as the most differentially expressed genes between treatment naïve chemotherapy resistant and sensitive tumours. Interferon-induced STAT1 is a transcription factor, which induces many genes including tumour suppressor genes and those involved in recruitment of immune cells to the tumour immune microenvironment (TME), including CXCL10. CXCL10 is a chemokine that recruits tumour infiltrating lymphocytes (TILs) and exhibits angiostatic function. The current study was performed to determine the effects of differential STAT1 and CXCL10 expression on HGSC disease progression and TME. STAT1 expression and intratumoural CD8+ T cells were evaluated as prognostic and predictive biomarkers via immunohistochemistry on 734 HGSC tumours accrued from the Terry Fox Research Institute-Canadian Ovarian Experimental Unified Resource. The combined effect of STAT1 expression and CD8+ TIL density was confirmed as prognostic and predictive companion biomarkers in the second independent biomarker validation study. Significant positive correlation between STAT1 expression and intratumoral CD8+ TIL density was observed. The effects of enforced CXCL10 expression on HGSC tumour growth, vasculature and immune tumour microenvironment were studied in the ID8 mouse ovarian cancer cell engraftment in immunocompetent C57BL/6 mice. Significant decrease in tumour progression in mice injected with ID8 CXCL10 overexpressing cells compared to mice injected with ID8 vector control cells was observed. Multiplexed cytokine analysis of ascites showed differential expression of IL-6, VEGF and CXCL9 between the two groups. Endothelial cell marker staining showed differences in tumour vasculature between the two groups. Immune transcriptomic profiling identified distinct expression profiles in genes associated with cytokines, chemokines, interferons, T cell function and apoptosis between the two groups. These findings provide evidence that STAT1 is an independent biomarker and in combination with CD8+ TIL density could be applied as novel immune-based biomarkers in HGSC. These results provide the basis for future studies aimed at understanding mechanisms underlying differential tumour STAT1 and CXCL10 expression and its role in pre-existing tumour immunologic diversity, thus potentially contributing to biomarker guided immune modulatory therapies.

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Several different acquired resistance mechanisms of EGFR mutant lung adenocarcinoma to EGFR-tyrosine kinase inhibitor (TKI) therapy have been described, most recently transformation to small cell lung carcinoma (SCLC). We describe the case of a 46-year-old female with relapsed EGFR exon 19 deletion lung adenocarcinoma treated with erlotinib, and on resistance, cisplatin-pemetrexed. Liver rebiopsy identified an afatinib-resistant combined SCLC and non-small cell carcinoma with neuroendocrine morphology, retaining the EGFR exon 19 deletion. This case highlights acquired EGFR-TKI resistance through transformation to the high-grade neuroendocrine carcinoma spectrum and that that such transformation may not be evident at time of progression on TKI therapy.

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Bragança and Morais Massifs are part of the mega-klippen ensemble of NW Iberia, comprising a tectonic pile of four allochthonous units stacked above the Central-Iberian Zone autochthon. On top of this pile, the Upper Allochthonous Terrane (UAT) includes different high-grade metamorphic series whose age and geodynamic meaning are controversial. Mafic granulites provided U–Pb zircon ages at 399±7 Ma, dating the Variscan emplacement of UAT. In contrast,U–Pb zircon ages of ky- and hb-eclogites, felsic/intermediate HP/HT-granulites and orthogneisses (ca. 500–480 Ma) are identical to those of gabbros (488 ± 10 Ma) and Grt-pyroxenites (495 ± 8 Ma) belonging to a mafic/ultramafic igneous suite that records upper mantle melting and mafic magma crustal underplating at these times. Gabbros intrude the high-grade units of UAT and did not underwent the HP metamorphic event experienced by eclogites and granulites. These features and the zircon dates resemblance among different lithologies, suggest that extensive age resetting of older events may have been correlative with the igneous suite emplacement/crystallisation. Accordingly, reconciliation of structural, petrological and geochronological evidence implies that the development and early deformation of UAT high-grade rocks should be ascribed to an orogenic cycle prior to ≈500 Ma. Undisputable dating of this cycle is impossible, but the sporadic vestiges of Cadomian ages cannot be disregarded. The ca. 500–480 Ma time-window harmonises well with the Lower Palaeozoic continental rifting that trace the VariscanWilson Cycle onset and the Rheic Ocean opening. Subsequent preservation of the high heat-flowregime, possibly related to the Palaeotethys back-arc basin development (ca. 450–420 Ma), would explain the 461 ± 10 Ma age yielded by some zircon domains in felsic granulites, conceivably reflecting zircon dissolution/ recrystallisation till Ordovician times, long before the Variscan paroxysm (ca. 400–390 Ma). This geodynamic scenario suggests also that UAT should have been part of Armorica before its emplacement on top of Iberia after Palaeotethys closure.

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The arginine methyltransferase CARM1 (PRMT4) is amplified and overexpressed in ~20% of high-grade serous ovarian cancer (HGSOC) and correlates with a poor survival. Therapeutic approaches based on CARM1 expression remain to be an unmet need. Here we show that fatty acid metabolism represents a metabolic vulnerability for HGSOC in a CARM1 expression status dependent manner. CARM1 promotes the de novo synthesis of fatty acids and monounsaturated fatty acids (MUFAs). The disruption of MUFAs synthesis by inhibition of SCD1 results in excessive accumulation of cytotoxic saturated fatty acids and it is synthetic lethal with CARM1 expression. Collectively, our data show that the pharmacological inhibition of MUFAs synthesis via SCD1 inhibition represents a therapeutic strategy for CARM1-high HGSOC. Another arginine methyltransferase, PRMT5, has been identified by our CRISPR screening analysis as a promising candidate for invasive ARID1A-deficient endometrial cancer. Endometrial Cancer frequently harbor somatic inactivating mutation of ARID1A that can promote an invasive phenotype. Our in vitro approach validated the CRISPR screening showing that both PRTM5 knock down and its pharmaceutical inhibition specifically hamper the invasion of ARID1A inactivated cells. Mechanistically, PRMT5 directly regulates the epithelia to mesenchymal transition pathway genes interacting with the SWI/SNF complexes. Moreover, in vivo experiments showed that PRMT5 inhibition contrasted the myometrium invasion highlighting PRMT5 inhibition as promising therapeutic strategy for ARID1A- inactivated aggressive endometrial cancer.

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Purpose The presence of hypoxic cells in high-grade glioma (HGG) is one of the main reasons of local failure after radiotherapy (RT). The use of hyperbaric oxygen therapy (HBO) could help to overcome the problem of hypoxia in poorly oxygenated regions of the tumor. We performed a pilot study to evaluate the efficacy of hypofractionated image-guided helical TomoTherapy (HT) after HBO in the treatment of recurrent HGG (rHGG). Methods We enrolled 15 patients (aged >18 years) with diagnosis of rHGG. A total dose of 15-25 Gy was administered in daily 5-Gy fractions for 3-5 consecutive days after daily HBO. Each fraction was delivered up to maximum of 60 minutes after HBO. Results Median follow-up from HBO-RT was 28.6 (range: 5.3-56.8). No patient was lost to follow-up. Median progression-free survival (mPFS) for all patients was 3.2 months (95% CI: 1.34- 6.4 ), while 3-month, 6-month and 12 month PFS was 60% (95%CI: 31.8.4-79.7), 40% (95%CI: 16.5- 62.8) and10.0 (0.8-33.5) , respectively. Median overall survival (mOS) of HBO-RT was 11.7 months (95% CI: 7.3-29.3), while 3-month, 6-month and 12 month OS was 100% , 93.3% (61.3-99.0) and 46.7 % (21.2-68.8). No acute or late neurologic toxicity >grade 2 (CTCAE version 4.3) was observed in 86.66% of patients. Two patients developed G3 Radionecrosis. Conclusion HSRT combined to HBO seems effective and safe in the treatment of rHGG. One of advantages of HBO-RT is the reduced overall treatment time (3-5 consecutive days).

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This study reports the nature and extent of open-system interaction between groundwater and a weathered profile developed in the high grade thorium and REE ore body in Morro do Ferro, Pocos de Caldas plateau. The radioelement mobility in the shallow oxidizing environment was considered by using chemical data in conjunction with U-234/U-238, Ra-226/Th-230, Th-230/U-234, Th-228/Th-232, Ra-228/Th-232 and Th-230/Ra-228 activity ratios (AR's) for borehole spoil and groundwater samples.Recharging groundwater from the studied borehole has low salinity values, with total dissolved solids content of 14.7 mg/l and total ionic strength of 0.00018. The ratio of the weight of dissolved radioelement per unit volume of solution to the weight of radioelement in solid phase per unit weight of solid phase showed that the radioelement solubility in the studied waters varied according to the following order: radium> uranium >thorium.U-234/U-238 AR's less than 1 were measured in solid phase and can justify the enhancement of U-234 in solution. Ra-226/Th-230 AR's greater than 1 and Th-230/U-234 AR'S less than 1 were evaluated between 20 and 27 m in depth, where a 2.1-m thick magnetite dike was intersected. These ratios could be justified by deposition of U and Ra associated with Fe-Mn oxides and kaolinite, where mineral saturation indices evaluated from the available data confirm this possibility. Covariations among disequilibria involving Th-228/(228) Ra and Ra-228/Th-232 AR's showed the preferential removal of Ra-228 relative to Tn isotopes, Th-228 and Th-232. The recent deposition of radium within the timescale of at least the last 35 years also is suggested. (C) 1998 Elsevier B.V. Ltd. All rights reserved.

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PURPOSE: The purpose of this study was to analyze the agreement between anal Pap smear and high-resolution anoscopy-guided biopsy in diagnosing anal dysplasia in HIV-infected patients. METHODS: We conducted cross-sectional analysis of HIV-infected patients receiving anal dysplasia screening as part of routine care. Agreement between measures was estimated by weighted kappa statistics, using a three-tiered cytologic and histologic grading system (normal, low-grade dysplasia, and high-grade dysplasia). Estimates of sensitivity, specificity, and predictive values were calculated using a two-tiered cytologic and histologic grading system (""without dysplasia"" and ""with dysplasia of any grade""). Estimates were also calculated for the detection of high-grade dysplasia. RESULTS: During a one-year period, 222 patients underwent 330 anal Pap smears followed by high-resolution anoscopy-guided biopsies. There were 311 satisfactory Pap smears with concurrent biopsies. Considering histology the standard, the frequency of anal dysplasia was 46%. Kappa agreement between anal Pap smear and biopsy was 0.20. For detection of anal dysplasia of any grade, anal Pap smear showed sensitivity of 61%, specificity of 60%, positive predictive value of 56%, and negative predictive value of 64%. For high-grade dysplasia, anal Pap smear showed sensitivity of 16% and specificity of 97%. CONCLUSION: Anal Pap smears alone were not sensitive enough to rule out anal dysplasia. We recommend that high-resolution anoscopy-guided biopsy be incorporated as a complementary screening test for anal dysplasia in high-risk patients. Following baseline high-resolution anoscopy, these individuals could be followed with serial anal cytology to dictate the need for future high-resolution anoscopy-guided biopsies.

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High risk of recurrence/progression bladder tumours is treated with Bacillus Calmette-Guérin (BCG) immunotherapy after complete resection of the tumour. Approximately 75% of these tumours express the uncommon carbohydrate antigen sialyl-Tn (Tn), a surrogate biomarker of tumour aggressiveness. Such changes in the glycosylation of cell-surface proteins influence tumour microenvironment and immune responses that may modulate treatment outcome and the course of disease. The aim of this work is to determine the efficiency of BCG immunotherapy against tumours expressing sTn and sTn-related antigen sialyl-6-T (s6T). METHODS: In a retrospective design, 94 tumours from patients treated with BCG were screened for sTn and s6T expression. In vitro studies were conducted to determine the interaction of BCG with high-grade bladder cancer cell line overexpressing sTn. RESULTS: From the 94 cases evaluated, 36 had recurrence after BCG treatment (38.3%). Treatment outcome was influenced by age over 65 years (HR=2.668; (1.344-5.254); P=0.005), maintenance schedule (HR=0.480; (0.246-0.936); P=0.031) and multifocality (HR=2.065; (1.033-4.126); P=0.040). sTn or s6T expression was associated with BCG response (P=0.024; P<0.0001) and with increased recurrence-free survival (P=0.001). Multivariate analyses showed that sTn and/or s6T were independent predictive markers of recurrence after BCG immunotherapy (HR=0.296; (0.148-0.594); P=0.001). In vitro studies demonstrated higher adhesion and internalisation of the bacillus to cells expressing sTn, promoting cell death. CONCLUSION: s6T is described for the first time in bladder tumours. Our data strongly suggest that BCG immunotherapy is efficient against sTn- and s6T-positive tumours. Furthermore, sTn and s6T expression are independent predictive markers of BCG treatment response and may be useful in the identification of patients who could benefit more from this immunotherapy.

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SUMMARY High-risk human papillomavirus (hr-HPV) infection is necessary but not sufficient for cervical cancer development. Recently, P16INK4A gene silencing through hypermethylation has been proposed as an important cofactor in cervical carcinogenesis due to its tumor suppressor function. We aimed to investigate P16INK4A methylation status in normal and neoplastic epithelia and evaluate an association with HPV infection and genotype. This cross-sectional study was performed with 141 cervical samples from patients attending Hospital Moncorvo Filho, Rio de Janeiro. HPV detection and genotyping were performed through PCR and P16INK4A methylation by nested-methylation specific PCR (MSP). HPV frequency was 62.4% (88/141). The most common HPV were HPV16 (37%), HPV18 (16.3%) and HPV33/45(15.2%). An upward trend was observed concerning P16INK4A methylation and lesion degree: normal epithelia (10.7%), low grade lesions (22.9%), high grade (57.1%) and carcinoma (93.1%) (p < 0.0001). A multivariate analysis was performed to evaluate an association between methylation, age, tobacco exposure, HPV infection and genotyping. A correlation was found concerning methylation with HPV infection (p < 0.0001), hr-HPV (p = 0.01), HSIL (p < 0.0007) and malignant lesions (p < 0.0001). Since viral infection and epigenetic alterations are related to cervical carcinoma, we suggest that P16INK4A methylation profile maybe thoroughly investigated as a biomarker to identify patients at risk of cancer.