U–Pb geochronology of deformation and metamorphism across a central transect of the Early Proterozoic Torngat Orogen, North River map area, Labrador

1993 ◽  
Vol 30 (7) ◽  
pp. 1470-1489 ◽  
Author(s):  
Jean-Michel Bertrand ◽  
J. Christopher Roddick ◽  
Martin J. van Kranendonk ◽  
Ingo Ermanovics
Keyword(s):  
Shear Zone ◽  
Stage Ii ◽  
Crustal Thickening ◽  
Stage Iii ◽  
Arc Magmatism ◽  
Oblique Collision ◽  
Early Proterozoic ◽  
Nappe Tectonics ◽  
Minimum Age ◽  
High Grade Metamorphism

The Early Proterozoic Torngat Orogen resulted from the oblique collision of the Archean Nain and southeastern Rae provinces and evolved in four stages: (0) deposition of platformal supracrustal assemblages followed by subduction-related arc magmatism in the margin of the Rae Province; (I) crustal thickening and nappe tectonics; (II) sinistral transpression and formation of the Abloviak shear zone; (III) uplift on steeply dipping, east-verging mylonites along the eastern orogenic front.U–Pb geochronology on zircon and monazite from major rock units and syntectonic intrusions indicates that arc magmatism at ca. 1880 Ma was followed by 40 Ma. of deformation and high-grade metamorphism from ca. 1860 to 1820. Subsequent uplift and final cooling occurred ca. 1795 – 1770 Ma. Several ages of mineral growth that correspond to distinct structural and metamorphic events have been recognized: (1) 1858 – 1853 Ma zircon and monazite dates are interpreted as the minimum age of stage I and peak metamorphic conditions; (2) 1844 Ma zircons from anatectic granitoids in the Tasiuyak gneiss complex (TGC), syntectonic with stage II deformation, are interpreted to date the formation of the Abloviak shear zone; (3) 1837 Ma magmatic zircons from an intrusive granite vein deformed along the western contact of the TGC represent a discrete intrusive event; (4) 1825 – 1822 Ma metamorphic overgrowths and newly grown zircons in granitic veins from the western portion of the orogen (Lac Lomier complex) represent a period of renewed transpressional deformation; (5) 1806 Ma magmatic zircons from a post-stage II granite emplaced along the eastern edge of the Abloviak shear zone defines the transition between stage II and stage III events; (6) 1794 – 1773 Ma zircons from leucogranites and pegmatites that are associated with uplift of the orogen (stage III). 1780 – 1740 Ma dates for monazite and a 40Ar/39Ar hornblende age correspond to the latest stages of uplift and cooling of the orogen.

Lithotectonic elements and tectonic evolution of Torngat Orogen, Saglek Fiord, northern Labrador

1991 ◽  
Vol 28 (9) ◽  
pp. 1407-1423 ◽  
Author(s):  
Flemming Mengel ◽  
Toby Rivers ◽  
Peter Reynolds
Keyword(s):  
Shear Zone ◽  
Frontal Zone ◽  
Crustal Thickening ◽  
Oblique Collision ◽  
Early Proterozoic ◽  
Collision Zone ◽  
Internal Zone ◽  
History Of ◽  
Peak Metamorphism ◽  
Normal Thickness

A cross section of the eastern part of the Early Proterozoic Torngat Orogen is exposed along Saglek Fiord in northern Labrador. It shows the transition from a foreland, through a frontal zone to the internal zone of the orogen, the latter being composed of two lithologically distinct terranes that are part of Abloviak shear zone, a crustal-scale transcurrent shear zone with a sinistral sense of displacement. One of these terranes is parautochthonous with respect to the foreland, the other is allochthonous and interpreted as being separated from the parautochthon by a cryptic suture.Ramah Group, an Early Proterozoic supracrustal sequence that lies unconformably on Archean gneisses in the foreland, can be traced across the frontal zone, but does not occur in Abloviak shear zone in the Saglek area.Tectonic evolution of Torngat Orogen involved crustal thickening to approximately double normal thickness, with transcurrent shearing of the thickened crust taking place during peak metamorphic conditions. Synmetamorphic uplift occurred synchronously with transcurrent shearing, and was followed by imbrication of orogenic zones along late thrust–reverse faults. Available age determinations suggest that peak metamorphism predated uplift by about 50 Ma. 39Ar/40Ar dating of hornblende from Abloviak shear zone has yielded ages of 1790–1750 Ma, some 15–65 Ma younger than recent estimates of the age of late faults, thus indicating slow and irregular uplift throughout the orogen.The orogenic history of Torngat Orogen is compatible with evolution in an oblique collision zone between two Archean cratonic blocks, and their subsequent welding into a single continental fragment that itself became incorporated into proto-Laurentia.

Identification of biomarkers and functional modules from genomic data in stage-wise breast cancer

2020 ◽  
Vol 15 ◽  
Author(s):  
Athira K ◽  
Vrinda C ◽  
Sunil Kumar P V ◽  
Gopakumar G
Keyword(s):  
Breast Cancer ◽  
Expression Patterns ◽  
Differential Expression Analysis ◽  
Predictive Biomarkers ◽  
Stage I ◽  
Stage Ii ◽  
Stage Iii ◽  
Functional Modules ◽  
Incidence And Mortality ◽  
Multiple Stages

Background: Breast cancer is the most common cancer in women across the world, with high incidence and mortality rates. Being a heterogeneous disease, gene expression profiling based analysis plays a significant role in understanding breast cancer. Since expression patterns of patients belonging to the same stage of breast cancer vary considerably, an integrated stage-wise analysis involving multiple samples is expected to give more comprehensive results and understanding of breast cancer. Objective: The objective of this study is to detect functionally significant modules from gene co-expression network of cancerous tissues and to extract prognostic genes related to multiple stages of breast cancer. Methods: To achieve this, a multiplex framework is modelled to map the multiple stages of breast cancer, which is followed by a modularity optimization method to identify functional modules from it. These functional modules are found to enrich many Gene Ontology terms significantly that are associated with cancer. Result and Discussion: predictive biomarkers are identified based on differential expression analysis of multiple stages of breast cancer. Conclusion: Our analysis identified 13 stage-I specific genes, 12 stage-II specific genes, and 42 stage-III specific genes that are significantly regulated and could be promising targets of breast cancer therapy. That apart, we could identify 29, 18 and 26 lncRNAs specific to stage I, stage II and stage III respectively.

Cardiac transthyretin wild-type amyloidosis (ATTRwt): a prospective study of 400 patients followed at the Italian referral center

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
P Milani ◽  
L Obici ◽  
R Mussinelli ◽  
M Basset ◽  
G Manfrinato ◽  
...  
Keyword(s):  
Natural History ◽  
Median Survival ◽  
Troponin I ◽  
Stage I ◽  
Stage Ii ◽  
Stage Iii ◽  
Wild Type ◽  
Staging Systems ◽  
Significant Difference ◽  
History Of

Abstract Background Cardiac wild type transthyretin (ATTRwt) amyloidosis, formerly known as senile systemic amyloidosis, is an increasingly recognized, progressive, and fatal cardiomyopathy. Two biomarkers staging systems were proposed based on NT-proBNP (in both cases) and troponin or estimated glomerular filtration rate, that are able to predict survival in this population. The availability of novel effective treatments requires large studies to describe the natural history of the disease in different populations. Objective To describe the natural history of the disease in a large, prospective, national series. Methods Starting in 2007, we protocolized data collection in all the patients diagnosed at our center (n=400 up to 7/2019). Results The referrals to our center increased over time: 5 cases (1%) between 2007–2009, 33 (9%) in 2010–2012, 90 (22%) in 2013–2015 and 272 (68%) in 2016–2019. Median age was 76 years [interquartile range (IQR): 71–80 years] and 372 patients (93%) were males. One hundred and seventy-three (43%) had atrial fibrillation, 63 (15%) had a history of ischemic cardiomyopathy and 64 (15%) underwent pacemaker or ICD implantation. NYHA class was I in 58 subjects (16%), II in 225 (63%) and III in 74 (21%). Median NT-proBNP was 3064 ng/L (IQR: 1817–5579 ng/L), troponin I 0.096 ng/mL (IQR: 0.063–0.158 ng/mL), eGFR 62 mL/min (IQR: 50–78 mL/min). Median IVS was 17 mm (IQR: 15–19 mm), PW 16 mm (IQR: 14–18 mm) and EF 53% (IQR: 45–57%). One-hundred and forty-eight subjects (37%) had a concomitant monoclonal component in serum and/or urine and/or an abnormal free light chain ratio. In these patients, the diagnosis was confirmed by immunoelectron microscopy or mass spectrometry. In 252 (63%) the diagnosis was based on bone scintigraphy. DNA analysis for amyloidogenic mutations in transthyretin and apolipoprotein A-I genes was negative in all subjects. The median survival of the whole cohort was 59 months. The Mayo Clinic staging based on NT-proBNP (cutoff: 3000 ng/L) and troponin I (cutoff: 0.1 ng/mL) discriminated 3 different groups [stage I: 131 (35%), stage II: 123 (32%) and stage III: 127 (33%)] with different survival between stage I and II (median 86 vs. 81 months, P=0.04) and between stage II and III (median 81 vs. 62 months, P<0.001). The UK staging system (NT-proBNP 3000 ng/L and eGFR 45 mL/min), discriminated three groups [stage I: 170 (45%), stage II: 165 (43%) and stage III: 45 (12%)] with a significant difference in survival: between stage I and stage II (86 vs. 52 months, P<0.001) and between stage II and stage III (median survival 52 vs. 33 months, P=0.045). Conclusions This is one of the largest series of patients with cardiac ATTRwt reported so far. Referrals and diagnoses increased exponentially in recent years, One-third of patients has a concomitant monoclonal gammopathy and needed tissue typing. Both the current staging systems offered good discrimination of staging and were validated in our independent cohort. Funding Acknowledgement Type of funding source: None

The efficacy of adjuvant chemotherapy for resected high-risk stage II and stage III colorectal cancer in frail patients

2021 ◽  
Author(s):  
Kosuke Mima ◽  
Nobutomo Miyanari ◽  
Keisuke Kosumi ◽  
Takuya Tajiri ◽  
Kosuke Kanemitsu ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
High Risk ◽  
Adjuvant Chemotherapy ◽  
Stage Ii ◽  
Stage Iii ◽  
Frail Patients

scholarly journals CXCR6-CXCL16 Axis Promotes Breast Cancer by Inducing Oncogenic Signaling

Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3568
Author(s):  
Hina Mir ◽  
Neeraj Kapur ◽  
Dominique N. Gales ◽  
Praveen K. Sharma ◽  
Gabriela Oprea-Ilies ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Actin Polymerization ◽  
Biological Significance ◽  
Stage Ii ◽  
Stage Iii ◽  
Soluble Form ◽  
Migration And Invasion ◽  
Antibody Microarray ◽  
Terminal Fragment ◽  
Significant Difference

Precise mechanisms underlying breast cancer (BrCa) metastasis are undefined, which becomes a challenge for effective treatments. Chemokine signaling instigates the trafficking of cancer cells in addition to leukocytes. This study aimed to ascertain the clinical and biological significance of the CXCR6/CXCL16 signaling axis in the pathobiology of BrCa. Our data show a higher expression of CXCR6 in BrCa cell lines and tissues. Stage-III BrCa tissues express significantly higher CXCR6 compared to stage-II tissues. The ligand, CXCL16, could remain tethered to the cell surface, and, after proteolytic shedding of the ectodomain, the N-terminal fragment is released, converting it to its oncogenic, soluble form. Like CXCR6, N-terminal CXCL16 and ADAM-10 were significantly higher in stage-III than stage-II, but no significant difference was observed in the C-terminal fragment of CXCL16. Further, stimulation of the CXCR6/CXCL16 axis activated Src, FAK, ERK1/2, and PI3K signaling pathways, as per antibody microarray analysis, which also underlie CXCL16-induced F-actin polymerization. The CXCR6/CXCL16 axis induces cytoskeleton rearrangement facilitating migration and invasion and supports BrCa cell survival by activating the PI3K/Akt pathway. This study highlights the significance of the CXCR6/CXCL16 axis and ADAM10 as potential therapeutic targets for advanced-stage BrCa.

Single Ventricle Palliation in a Developing Sub-Saharan African Country: What Should be Improved?

2019 ◽  
Vol 10 (2) ◽  
pp. 164-170 ◽  
Author(s):  
Valdano Manuel ◽  
Humberto Morais ◽  
Aida L. R. Turquetto ◽  
Gade Miguel ◽  
Leonardo A. Miana ◽  
...  
Keyword(s):  
Confidence Interval ◽  
African Country ◽  
Single Ventricle ◽  
Hazard Ratio ◽  
Stage I ◽  
Stage Ii ◽  
Stage Iii ◽  
Lost To Follow Up ◽  
Single Ventricle Palliation

Introduction: Single ventricle physiology management is challenging, especially in low-income countries. Objective: To report the palliation outcomes of single ventricle patients in a developing African country. Methods: We retrospectively studied 83 consecutive patients subjected to single ventricle palliation in a single center between March 2011 and December 2017. Preoperative data, surgical factors, postoperative results, and survival outcomes were analyzed. The patients were divided by palliation stage: I (pulmonary artery banding [PAB] or Blalock–Taussig shunt [BTS]), II (Glenn procedure), or III (Fontan procedure). Results: Of the 83 patients who underwent palliation (stages I-III), 38 deaths were observed (31 after stage I, six after stage II, and one after stage III) for an overall mortality of 45.7%. The main causes of operative mortality were multiple organ dysfunction due to sepsis, shunt occlusion, and cardiogenic shock. Twenty-eight survivors were lost to follow-up (22 after stage I, six after stage II). Thirteen stage II survivors are still waiting for stage III. The mean follow-up was 366 ± 369 days. Five-year survival was 28.4 % for PAB and 30.1% for BTS, while that for stage II and III was 49.8% and 57.1%, respectively. Age (hazard ratio, 0.61; 95% confidence interval: 0.47-0.7; P = .000) and weight at surgery (hazard ratio, 0.45; 95% confidence interval: 0.31-0.64; P = .002) impacted survival. Conclusion: A high-mortality rate was observed in this initial experience, mainly in stage I patients. A large number of patients were lost to follow-up. A task force to improve outcomes is urgently required.

scholarly journals Impact of the Number of Dissected Lymph Nodes on Survival for Gastric Cancer after Distal Subtotal Gastrectomy

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Chang-Ming Huang ◽  
Jian-Xian Lin ◽  
Chao-Hui Zheng ◽  
Ping Li ◽  
Jian-Wei Xie ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Survival Rate ◽  
Lymph Nodes ◽  
Distal Gastrectomy ◽  
Stage I ◽  
Stage Ii ◽  
Stage Iii ◽  
Prognostic Impact ◽  
Term Survival

Objectives. To investigate the prognostic impact of the number of dissected lymph nodes (LNs) in gastric cancer after curative distal gastrectomy.Methods. The survival of 634 patients who underwent curative distal gastrectomy from 1995 to 2004 was retrieved. Long-term surgical outcomes and associations between the number of dissected LNs and the 5-year survival rate were investigated.Results. The number of dissected LNs was one of the most important prognostic indicators. Among patients with comparable T category, the larger the number of dissected LNs was, the better the survival would be (). The linear regression showed that a significant survival improvement based on increasing retrieved LNs for stage II, III and IV (). A cut-point analysis yields the greatest variance of survival rate difference at the levels of 15 LNs (stage I), 25 LNs (stage II) and 30 LNs (stage III).Conclusion. The number of dissected LNs is an independent prognostic factor for gastric cancer. To improve the long-term survival of patients with gastric cancer, removing at least 15 LNs for stage I, 25 LNs for stage II, and 30 LNs for stage III patients during curative distal gastrectomy is recommended.

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