229 resultados para PP-MA
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Some of the anti-neoplastic effects of anthracyclines in mice originate from the induction of innate and T cell-mediated anticancer immune responses. Here we demonstrate that anthracyclines stimulate the rapid production of type I interferons (IFNs) by malignant cells after activation of the endosomal pattern recognition receptor Toll-like receptor 3 (TLR3). By binding to IFN-α and IFN-β receptors (IFNARs) on neoplastic cells, type I IFNs trigger autocrine and paracrine circuitries that result in the release of chemokine (C-X-C motif) ligand 10 (CXCL10). Tumors lacking Tlr3 or Ifnar failed to respond to chemotherapy unless type I IFN or Cxcl10, respectively, was artificially supplied. Moreover, a type I IFN-related signature predicted clinical responses to anthracycline-based chemotherapy in several independent cohorts of patients with breast carcinoma characterized by poor prognosis. Our data suggest that anthracycline-mediated immune responses mimic those induced by viral pathogens. We surmise that such 'viral mimicry' constitutes a hallmark of successful chemotherapy.
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Percutaneous closure of patent foramen ovale (PFO) has been proposed as the treatment of choice for young high-risk patients who suffered cryptogenic stroke and/or peripheral paradoxical embolism. We sought to compare prospectively two different devices used for percutaneous PFO closure.Prospective data were collected on 40 high risk patients (females: 38%, mean age : 44 +/- 11 years, interatrial septal aneurysm >10 mm: 68%) who underwent percutaneous PFO closure after cryptogenic stroke (n = 38) or peripheral paradoxical embolism (n = 2). Chronologically, 20 patients were first treated by a PFO-Star (Cardia, Burnsville, MI) device. Then, 20 other patients received a Starflex occluder (NMT, Boston, MA). The primary endpoint was complete PFO closure at 6 months as assessed by transthoracic contrast echocardiography. Secondary endpoints were major peri- or post procedural complications and clinical recurrence at 1 year follow-up.Baseline clinical and anatomical characteristics were comparable for both groups. Complete PFO closure was observed in 50% (PFO-Star) and 90% (Starflex) of patients (p=0.001) respectively. Major peri-procedural complications occurred in the PFO-star group only: right-sided device thrombus (1 patient) and aorto-right atrial fistula (1 patient). At 1 year follow-up, no clinical recurrence occurred.In conclusion, despite the absence of clinical recurrence in this high-risk population with presumed paradoxical embolism, complete PFO closure at 6 months follow-up was significantly related to the type of closure device used
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Granitic and mafic magma pulses were sequentially accreted in the spectacularly exposed shallow crustal Torres del Paine laccolith, in southern Patagonia. This 12.5 Ma pluton forms a composite intrusion with a subvertical feeding system in the west and a laccolith in the east. A key unknown in the formation of sill complexes is how individual magma pulses are assembled over time and the geometry and localization of their feeding system. High resolution zircon CA-ID-TIMS U-Pb dating shows that the laccolith grew first by under-accretion of granitic sills over 90 +/- 30 ka, linked to a `sheet-like' feeding system, followed by underplating of mafic sills after similar to 20 ka of quiescence. In the mafic sills complex, individual sills were injected by over-accretion during 41 +/- 11 ka. Our data show that successive granitic and mafic magmas emplacement generated a volume of similar to 88 km(3) in 162 +/- 11 ka. (C) 2012 Elsevier B.V. All rights reserved.
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A metasomatic diopside rock occurs at the top of the dolomitic Connemara Marble Formation of western Ireland and contains titanite and K-feldspar in addition to around 90% diopside (X(Mg) = 0.90-0.97). U-Pb isotopic measurements on this mineral assemblage show that the titanite is both unusually uranium-rich and isotopically concordant, with the result that a precise U-Pb age of 478 +/- 2.5 Ma can be determined. The age is identical within error to a less precise Rb-Sr age of diopside-K-feldspar of 483 +/- 6 Ma. Petrological evidence indicates that the assemblage crystallized at c. 620-degrees-C close to or below the closure temperature of titanite. The age thus provides a precise estimate of the time of metamorphism; this age is 11 +/- 3 Ma younger than the 490 Ma age for nearby gabbroic plutons which has previously been used to constrain the peak metamorphic age. This difference accords well with geological evidence that the gabbros were emplaced prior to the metamorphic peak. Analysis of minerals with high closure temperature from assemblages whose crystallization is unambiguously associated with a specific episode of fluid infiltration at the peak of metamorphism provides the basis for a new approach to dating metamorphism. The success of this approach is demonstrated by the results from Connemara.
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BACKGROUND: Early detection is a major goal in the management of malignant melanoma. Besides clinical assessment many noninvasive technologies such as dermoscopy, digital dermoscopy and in vivo laser scanner microscopy are used as additional methods. Herein we tested a system to assess lesional perfusion as a tool for early melanoma detection.¦METHODS: Laser Doppler flow (FluxExplorer) and mole analyser (MA) score (FotoFinder) were applied to histologically verified melanocytic nevi (33) and malignant melanomas (12).¦RESULTS: Mean perfusion and MA scores were significantly increased in melanoma compared to nevi. However, applying an empirically determined threshold of 16% perfusion increase only 42% of the melanomas fulfilled the criterion of malignancy, whereas with the mole analyzer score 82% of the melanomas fulfilled the criterion of malignancy.¦CONCLUSION: Laser Doppler imaging is a highly sensitive technology to assess skin and skin tumor perfusion in vivo. Although mean perfusion is higher in melanomas compared to nevi the high numbers of false negative results hamper the use of this technology for early melanoma detection.
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A 1 200 km-long linear magmatic belt extends along the Mediterranean coast the Maghreb from Eastern Tunisia to Morocco. This belt is mainly composed of Langan calc-alkaline metaluminous to peraluminous granitoids and associated andesites/cites Central and Eastern Algeria. In Tunisia and Oranie/Western Morocco, calc alkaline activity started later (during the Serravallian) and was followed by the placement of alkali basalts and basanites since the Tortonian to the Pliocene and, in me places, the Pleistocene. Available data on the tectonic setting, petrology, age and biochemistry of this belt show that most of its striking features, e.g. (1) very low magma production rate, subduction-related geochemical imprint, extensive crustal contamination the calc-alkaline magmatism and (2) progressive magmatic change from calc-alkaline alkaline, are consistent with magma generation during a slab breakoff process as proposed Carminati et al, in 1998. The magmatism associated with this breakoff started in Central Eastern Algeria at 16 Ma, then propagated eastwards and westwards, The upward of asthenospheric enriched plume-type mantle through the tear in the downgoing first triggered melting of the overlying lithospheric mantle which had been metasomatised during a previous subduction period. Heat supply from this uprising asthenosphere may have warmed up the continental crust and made its involvement in assimilation processes easier. As the asthenosphere ascended through the `window' in the slab, partial melting occurred at the uprising boundary between asthenosphere and lithosphere, generating basalts with transitional characteristics between those of calc-alkaline and alkaline basalts. As the asthhenospheric upwelling proceeded partial:melting then occurred in the sole asthenospheric mantle, producing alkali basalts. (C) 2000 Academie des sciences Editions scientifiques et medicales Elsevier SAS.
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The Guelb Moghrein Fe oxide-Cu-Au-Co deposit is located at the western boundary of the West African craton in NW Mauritania. The wall rocks to the mineralization represent a meta-volcanosedimentary succession typical of Archaean greenstone belts. Two types of meta-volcanic rocks are distinguished: (1) volcanoclastic rocks of rhyodacite-dacite composition (Sainte Barbe volcanic unit), which form the stratigraphic base; (2) tholeiitic andesites-basalts (Akjoujt meta-basalt unit). The trace element signature of both types is characteristic of a volcanic arc setting. A small meta-pelitic division belongs to the Sainte Barbe volcanic unit. A meta-carbonate body, which contains the mineralization, forms a tectonic lens in the Akjoujt meta-basalt unit. It can be defined by the high X(mg) (=36) of Fe-Mg carbonate, the REE pattern and the delta(13)C values of -18 to -17 parts per thousand as a marine precipitate similar to Archaean banded iron formation (BIF). Additionally, small slices of Fe-Mg clinoamphibole-chlorite schist in the meta-carbonate show characteristics of marine shale. This assemblage, therefore, does not represent an alteration product, but represents an iron formation unit deposited on a continental shelf, which probably belongs to the Lembeitih Formation. The hydrothermal mineralization at 2492 Ma was contemporaneous with regional D(2) thrusting of the Sainte Barbe volcanic unit and imbrications of the meta-carbonate in the upper greenschist facies. This resulted in the formation of an ore breccia in the meta-carbonate, which is enriched in Fe, Ni, Co, Cu, Bi, Mo, As and Au. Massive sulphide ore breccia contains up to 20 wt% Cu. The ore fluid was aqueous-carbonic in nature and either changed its composition from a Mg-rich oxidizing to an Fe-rich reducing fluid or the two fluid types mixed at the trap site. All lithologies at Guelb Moghrein were deformed by D(3) thrusting to the east in the lower greenschist facies. The mobility of REE in the retrogressed rocks explains the formation of a second generation of hydrothermal monazite, which was dated at c. 1742 Ma. Archaean rocks of the West African craton extend to the west to Guelb Moghrein. The active continental margin was deformed and mineralized in the Late Archaean-Early Proterozoic and again reactivated in the Mid-Proterozoic and Westphalian, showing that the western boundary of the craton was reactivated several times.
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PURPOSE: The recent increase in drug-resistant micro-organisms complicates the management of hospital-acquired bloodstream infections (HA-BSIs). We investigated the epidemiology of HA-BSI and evaluated the impact of drug resistance on outcomes of critically ill patients, controlling for patient characteristics and infection management. METHODS: A prospective, multicentre non-representative cohort study was conducted in 162 intensive care units (ICUs) in 24 countries. RESULTS: We included 1,156 patients [mean ± standard deviation (SD) age, 59.5 ± 17.7 years; 65 % males; mean ± SD Simplified Acute Physiology Score (SAPS) II score, 50 ± 17] with HA-BSIs, of which 76 % were ICU-acquired. Median time to diagnosis was 14 [interquartile range (IQR), 7-26] days after hospital admission. Polymicrobial infections accounted for 12 % of cases. Among monomicrobial infections, 58.3 % were gram-negative, 32.8 % gram-positive, 7.8 % fungal and 1.2 % due to strict anaerobes. Overall, 629 (47.8 %) isolates were multidrug-resistant (MDR), including 270 (20.5 %) extensively resistant (XDR), and 5 (0.4 %) pan-drug-resistant (PDR). Micro-organism distribution and MDR occurrence varied significantly (p < 0.001) by country. The 28-day all-cause fatality rate was 36 %. In the multivariable model including micro-organism, patient and centre variables, independent predictors of 28-day mortality included MDR isolate [odds ratio (OR), 1.49; 95 % confidence interval (95 %CI), 1.07-2.06], uncontrolled infection source (OR, 5.86; 95 %CI, 2.5-13.9) and timing to adequate treatment (before day 6 since blood culture collection versus never, OR, 0.38; 95 %CI, 0.23-0.63; since day 6 versus never, OR, 0.20; 95 %CI, 0.08-0.47). CONCLUSIONS: MDR and XDR bacteria (especially gram-negative) are common in HA-BSIs in critically ill patients and are associated with increased 28-day mortality. Intensified efforts to prevent HA-BSIs and to optimize their management through adequate source control and antibiotic therapy are needed to improve outcomes.
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New zircon U-Pb ages are proposed for late Early and Middle Triassic volcanic ash layers from the Luolou and Baifeng formations (northwestern Guangxi, South China). These ages are based on analyses of single, thermally annealed and chemically abraded zircons. Calibration with ammonoid ages indicate a 250.6 +/- 0.5 Ma age for the early Spathian Tirolites/Columbites beds, a 248.1 +/- 0.4 Ma age for the late Spathian Neopopanoceras haugi Zone, a 246.9 +/- 0.4 Ma age for the early middle Anisian Acrochordiceras hyatti Zone, and a 244.6 +/- 0.5 Ma age for the late middle Anisian Balatonites shoshonensis Zone. The new dates and previously published U-Pb ages indicate a duration of ca. 3 my for the Spathian, and minimal durations of 4.5 +/- 0.6 my for the Early Triassic and of 6.6+0.7/-0.9 my for the Anisian. The new Spathian dates are in a better agreement with a 252.6 +/- 0.2 Ma age than with a 251.4 +/- 0.3 Ma age for the Permian-Triassic boundary. These dates also highlight the extremely uneven duration of the four Early Triassic substages (Griesbachian, Dienerian, Smithian, and Spathian), of which the Spathian exceeds half of the duration of the entire Early Triassic. The simplistic assumption of equal duration of the four Early Triassic subdivisions is no longer tenable for the reconstruction of recovery patterns following the end Permian mass extinction. (c) 2006 Elsevier B.V. All rights reserved.
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The Himalayan orogen is the result of the collision between the Indian and Asian continents that began 55-50 Ma ago, causing intracontinental thrusting and nappe formation. Detailed mapping as well as structural and microfabric analyses on a traverse from the Tethyan Himalaya southwestward through the High Himalayan Crystalline and the Main Central Thrust zone (MCT zone) to the Lesser Himalayan Sequence in the Spiti-eastern Lahul-Parvati valley area reveal eight main phases of deformation, a series of late stage phases and five stages of metamorphic crystallization. This sequence of events is integrated into a reconstruction of the tectonometamorphic evolution of the Himalayan orogen in northern Himachal Pradesh. The oldest phase D-1 is preserved as relies in the High Himalayan Crystalline. Its deformational conditions are poorly known, but the metamorphic evolution is well documented by a prograde metamorphism reaching peak conditions within the upper amphibolite facies. This indicates that D-1 was an important tectonometamorphic event including considerable crustal thickening. The structural, metamorphic and sedimentary record suggest that D-1 most probably represents an early stage of continental collision. The first event clearly attributed to the collision between India and Asia is documented by two converging nappe systems, the NE-verging Shikar Beh Nappe and the SW-verging north Himalayan nappes. The D-2 Shikar Beh Nappe is characterized by isoclinal folding and top-to-the NE shearing, representing the main deformation in the High Himalayan Crystalline. D-2 also caused the main metamorphism in the High Himalayan Crystalline that was of a Barrovian-type, reaching upper amphibolite facies peak conditions. The Shikar Beh Nappe is interpreted to have formed within the Indian crust SW of the subduction zone. Simultaneously with NE-directed nappe formation, incipient subduction of India below Asia caused stacking of the SW-verging north Himalayan Nappes, that were thrust from the northern edge of the subducted continent toward the front of the Shikar Beh Nappe. As a result, the SW-verging folds of the D-3 Main Fold Zone formed in the Tethyan Himalaya below the front of the north Himalayan nappes. D-3 represents the main deformation in the Tethyan Himalaya, associated with a greenschist facies metamorphism. Folding within the Main Fold Zone subsequently propagated toward SW into the High Himalayan Crystalline, where it overprinted the preexisting D-2 structures. After subduction at the base of the north Himalayan nappes, the subduction zone stepped to the base of the High Himalayan Crystalline, where D-3 folds were crosscut by SW-directed D-4 thrusting. During D-4, the Crystalline Nappe, comprising the Main Fold Zone and relies of the Shikar Beh Nappe was thrust toward SW over the Lesser Himalayan Sequence along the 4 to 5 kms thick Main Central Thrust zone. Thrusting was related to a retrograde greenschist facies overprint at the base of the Crystalline Nappe and to pro-grade greenschist facies conditions in the Lesser Himalayan Sequence. Simultaneously with thrusting at the base of the Crystalline Nappe, higher crustal levels were affected by NE-directed D-5 normal extensional shearing and by dextral strike-slip motion, indicating that the high-grade metamorphic Crystalline Nappe was extruded between the low-grade metamorphic Lesser Himalayan Sequence at the base and the north Himalayan nappes at the top. The upper boundary of the Crystalline Nappe is not clearly delimited and passes gradually into the low-grade rocks at the front of the north Himalayan nappes. Extrusion of the Crystalline Nappe was followed by the phase D-6, characterized by large-scale, upright to steeply inclined, NE-verging folds and by another series of normal and extensional structures D-7+D-8 that may be related to ongoing extrusion of the Crystalline Nappe. The late stage evolution is represented by the phases D-A and D-B that indicate shortening parallel to the axis of the mountain chain and by D-C that is interpreted to account for the formation of large-scale domes with NNW-SSE-trending axes, an example of which is exposed in the Larji-Kullu-Rampur tectonic window.
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The distinct core-to-rim zonation of different REEs in garnet in metamorphic rocks, specifically Sm relative to Lu, suggests that Sm-Nd and Lu-Hf isochron ages will record different times along a prograde garnet growth history. Therefore, REE zonations in garnet must be measured in order to correctly interpret the isochron ages in terms of the garnet growth interval, which could span several m.y. New REE profiles, garnet crystal size distributions, and garnet growth modeling, combined with previously published Sm-Nd and Lu-Hf geochronology on a UHP eclogite of the Zermatt-Saas Fee (ZSF) ophiolite, Lago di Cignana (Italy), demonstrate that prograde garnet growth of this sample occurred over a similar to 30 to 40 m.y. interval. Relative to peak metamorphism at 38 to 40 Ma, garnet growth is estimated to have begun at similar to 11 to 14 kbar pressure at similar to 70 to 80 Ma. Although such a protracted garnet growth interval is surprising, this is supported by plate tectonic reconstructions which suggest that subduction of the Liguro-Piemont ocean occurred through slow and oblique convergence. These results demonstrate that REE zonations in garnet, coupled to crystal size distributions, provide a powerful means for understanding prograde metamorphic paths when combined with Sm-Nd and Lu-Hf geochronology. (C) 2009 Elsevier B.V. All rights reserved.
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Hydrogen isotope and Ar-40/Ar-39 geochronological data are presented from muscovite within a crustal-scale extensional detachment of the Shuswap Metamorphic Complex, North American Cordillera. The hydrogen isotope compositions (deltaD(ms)) of precisely dated muscovite attain values as low as -156parts per thousand in the detachment mylonite, whereas footwall quartzite has a deltaD(ms) value of -81parts per thousand. The very low deltaD(ms) values in the detachment are best explained by infiltration of meteoric water, with maximum deltaD values of -135parts per thousand +/- 3parts per thousand, during extensional unroofing of the orogen at 49.0-47.9 Ma. On the basis of the empirically determined relationship between elevation and isotopic composition of precipitation, the reconstructed early Eocene paleoelevations of the orogen are 4060 +/- 250 m to 4320 +/- 250 m, at least 1000 m higher than the highest present-day peaks. We propose that the isotopic composition of surface-derived waters in extensional detachments represents a newly recognized method to estimate maximum paleoelevations attained immediately preceding extensional orogenic collapse.
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In the Cape Caribou River allochthon (CCRA), metaigneous and gneissic units occur as a shallowly plunging synform in the hanging wall of the Grand Lake thrust system (GLTS), a Grenvillian structure that forms the boundary between the Mealy Mountains and Groswater Bay terranes. The layered rocks of the CCRA are cut by a stockwork of monzonite dykes related to the Dome Mountain suite and by metadiabase-amphibolite dykes that probably form part of the ca. 1380 Ma Mealy swarm. The mafic dykes appear to postdate much of the development of subhorizontal metamorphic layering within the lower parts of the CCRA. The uppermost (least metamorphosed) units of the CCRA, the North West River anorthosite-metagabbro and the Dome Mountain monzonite suite, have been dated at 1625 +/- 6 and 1626 +/- 2 Ma, respectively. An amphibolite unit that concordantly underlies the anorthosite-metagabbro and is intruded discordantly by monzonite dykes has given metamorphic ages of 1660 +/- 3 and 1631 +/- 2 Ma. Granitoid gneisses that form the lowest level of the CCRA have given a migmatization age of 1622 +/- 6 Ma. The effects of Grenvillian metamorphism become apparent in the lower levels of the allochthon where gneisses, amphibolite, and mafic dykes have given new generation zircon ages of 1008 +/- 2, 1012 +/- 3, and 1011 +/- 3 Ma, respectively. A posttectonic pegmatite has also given zircon and monazite ages of 1016(-3)(+7) and 1013 +/- 3 Ma, respectively. Although these results indicate new growth of Grenvillian zircon, this process was generally not accompanied by penetrative deformation or melting. Thus, the formation of gneissic fabrics and the overall layered nature of the lower CCRA are a result primarily of Labradorian (1660-1620 Ma) tectonism and intrusion, and probably reflect early movement on an ancestral GLTS. Grenvillian heating and metamorphism (up to granulite facies) was strongly concentrated towards the base of the CCRA and probably occurred during northwestward thrusting of the allochthon over the Groswater Bay terrane.
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Aims and background. In 2002, a survey including 1759 patients treated from 1980 to 1998 established a "benchmark" Italian data source for prostate cancer radiotherapy. This report updates the previous one. Methods. Data on clinical management and outcomes of 3001 patients treated in 15 centers from 1999 through 2003 were analyzed and compared with those of the previous survey. Results. Significant differences in clinical management (-10% had abdominal ma-gnetic resonance imaging; +26% received ≥70 Gy, +48% conformal radiotherapy, -20% pelvic radiotherapy) and in G3-4 toxicity rates (-3.8%) were recorded. Actuarial 5-year overall, disease-specific, clinical relapse-free, and biochemical relapse-free survival rates were 88%, 96%, 96% and 88%, respectively. At multivariate analysis, D'Amico risk categories significantly impacted on all the outcomes; higher radiotherapy doses were significantly related with better overall survival rates, and a similar trend was evident for disease-specific and biochemical relapse-free survival; cumulative probability of 5-year late G1-4 toxicity was 24.8% and was significantly related to higher radiotherapy doses (P <0.001). Conclusions. The changing patterns of practice described seem related to an improvement in efficacy and safety of radiotherapy for prostate cancer. However, the impact of the new radiotherapy techniques should be prospectively evaluated.