RESUMEN
Fly-ash particles formed during industrial fossil-fuel combustion show a globally observed rapid increase in concentration within natural archives post-1950 and have been proposed as a marker for the Anthropocene Epoch. Here, we present the first record of fly-ash particles incorporated into coral skeletons. Particles are present in Mediterranean corals between CE 1957 and 1992 at concentrations of 8-30 g-1 coral, mirroring the period of increased industrial activity in the area, and corroborating with spheroidal carbonaceous particle (SCP) records globally. The findings have important implications for the use of SCPs as markers in natural archives. With the exception of microplastics, this is the first evidence of particulate contamination in corals collected from natural environments. Further research is needed to understand incorporation pathways into coral skeletons, any subsequent ecotoxicological impact of contaminants, and the influence on overall coral health globally.
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Antozoos , Animales , Antozoos/metabolismo , Ceniza del Carbón , Plásticos/metabolismo , Combustibles Fósiles , Carbón Mineral , Arrecifes de CoralRESUMEN
Small changes in Pacific temperature gradients connected with the El Niño Southern Oscillation (ENSO) influence the Walker Circulation and are related to global climate anomalies. Therefore, it is of paramount importance to develop robust indices of their past behavior. Here, we reconstruct the difference in sea surface temperature between the west and central Pacific during ENSO, coined the West Pacific Gradient (WPG), based on the Last Millennium Paleo Hydrodynamics Data Assimilation. We show that the WPG tracks ENSO variability and strongly co-varies with the zonal gradient in Pacific sea surface temperature. We demonstrate that the WPG strength is related to significant atmospheric circulation and precipitation anomalies during historical El Niño and La Niña events by magnifying or weakening droughts and pluvials across the Indo-Pacific. We show that an extreme negative WPG coupled to a strong zonal Pacific temperature gradient is associated with enhanced megadroughts in North America between 1400 CE and the late sixteenth century. The twentieth century stands out in showing the most extreme swings between positive and negative WPG conditions over the past Millennium. We conclude that the WPG is a robust index together with ENSO indices to reveal past changes in Pacific zonal sea surface temperature gradient variability.
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Despite multidisciplinary local and systemic therapeutic approaches, the prognosis for most patients with brain metastases is still dismal. The role of adaptive and innate anti-tumor response including the Human Leukocyte Antigen (HLA) machinery of antigen presentation is still unclear. We present data on the HLA class II-chaperone molecule CD74 in brain metastases and its impact on the HLA peptidome complexity.We analyzed CD74 and HLA class II expression on tumor cells in a subset of 236 human brain metastases, primary tumors and peripheral metastases of different entities in association with clinical data including overall survival. Additionally, we assessed whole DNA methylome profiles including CD74 promoter methylation and differential methylation in 21 brain metastases. We analyzed the effects of a siRNA mediated CD74 knockdown on HLA-expression and HLA peptidome composition in a brain metastatic melanoma cell line.We observed that CD74 expression on tumor cells is a strong positive prognostic marker in brain metastasis patients and positively associated with tumor-infiltrating T-lymphocytes (TILs). Whole DNA methylome analysis suggested that CD74 tumor cell expression might be regulated epigenetically via CD74 promoter methylation. CD74high and TILhigh tumors displayed a differential DNA methylation pattern with highest enrichment scores for antigen processing and presentation. Furthermore, CD74 knockdown in vitro lead to a reduction of HLA class II peptidome complexity, while HLA class I peptidome remained unaffected.In summary, our results demonstrate that a functional HLA class II processing machinery in brain metastatic tumor cells, reflected by a high expression of CD74 and a complex tumor cell HLA peptidome, seems to be crucial for better patient prognosis.
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Antígenos CD/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundario , Genes MHC Clase II , Sialiltransferasas/metabolismo , Antígenos CD/genética , Biomarcadores de Tumor/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/mortalidad , Línea Celular Tumoral , Estudios de Cohortes , Metilación de ADN , Técnicas de Silenciamiento del Gen , Humanos , Estimación de Kaplan-Meier , Melanoma/metabolismo , Melanoma/patología , Pronóstico , Regiones Promotoras Genéticas , Sialiltransferasas/genética , Linfocitos T/metabolismo , Linfocitos T/patologíaRESUMEN
The western Indian Ocean has been warming faster than any other tropical ocean during the 20th century, and is the largest contributor to the global mean sea surface temperature (SST) rise. However, the temporal pattern of Indian Ocean warming is poorly constrained and depends on the historical SST product. As all SST products are derived from the International Comprehensive Ocean-Atmosphere dataset (ICOADS), it is challenging to evaluate which product is superior. Here, we present a new, independent SST reconstruction from a set of Porites coral geochemical records from the western Indian Ocean. Our coral reconstruction shows that the World War II bias in the historical sea surface temperature record is the main reason for the differences between the SST products, and affects western Indian Ocean and global mean temperature trends. The 20th century Indian Ocean warming pattern portrayed by the corals is consistent with the SST product from the Hadley Centre (HadSST3), and suggests that the latter should be used in climate studies that include Indian Ocean SSTs. Our data shows that multi-core coral temperature reconstructions help to evaluate the SST products. Proxy records can provide estimates of 20th century SST that are truly independent from the ICOADS data base.
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Cambio Climático/historia , Meteorología/métodos , Animales , Antozoos/crecimiento & desarrollo , Antozoos/fisiología , Atmósfera , Clima , Ecosistema , Historia del Siglo XIX , Historia del Siglo XX , Océano Índico , Agua de Mar , Temperatura , Segunda Guerra MundialRESUMEN
Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940-2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997-98 El Niño. We assess the impact of past warming events on coral extension rates and geochemical proxies. A marked decrease in coral (Pseudodiploria strigosa) extension rates coincides with a baseline shift to more negative values in oxygen and carbon isotopic composition after 1997-98, while a neighboring coral (Siderastrea siderea) recovered to pre-bleaching extension rates simultaneously. However, other stressors, besides high temperature, might also have influenced coral physiology and geochemistry. Coastal Venezuelan reefs were exposed to a series of extreme environmental fluctuations since the mid-1990s, i.e. upwelling, extreme rainfall and sediment input from landslides. This work provides important new data on the potential impacts of multiple regional stress events on coral isotopic compositions and raises questions about the long-term influence on coral-based paleoclimate reconstructions.
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Antozoos/metabolismo , Carbonato de Calcio/análisis , Calcio/análisis , Cambio Climático , El Niño Oscilación del Sur , Estroncio/análisis , Animales , Arrecifes de Coral , Calor , Océanos y Mares , VenezuelaRESUMEN
Increasing intensity of marine heatwaves has caused widespread mass coral bleaching events, threatening the integrity and functional diversity of coral reefs. Here we demonstrate the role of inter-ocean coupling in amplifying thermal stress on reefs in the poorly studied southeast Indian Ocean (SEIO), through a robust 215-year (1795-2010) geochemical coral proxy sea surface temperature (SST) record. We show that marine heatwaves affecting the SEIO are linked to the behaviour of the Western Pacific Warm Pool on decadal to centennial timescales, and are most pronounced when an anomalously strong zonal SST gradient between the western and central Pacific co-occurs with strong La Niña's. This SST gradient forces large-scale changes in heat flux that exacerbate SEIO heatwaves. Better understanding of the zonal SST gradient in the Western Pacific is expected to improve projections of the frequency of extreme SEIO heatwaves and their ecological impacts on the important coral reef ecosystems off Western Australia.
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Antozoos/fisiología , Arrecifes de Coral , Ecosistema , Calor , Estrés Fisiológico/fisiología , Animales , Océano Índico , Océano Pacífico , Agua de Mar , Australia OccidentalRESUMEN
Variability of the Leeuwin current (LC) off Western Australia is a footprint of interannual and decadal climate variations in the tropical Indo-Pacific. La Niña events often result in a strengthened LC, high coastal sea levels and unusually warm sea surface temperatures (SSTs), termed Ningaloo Niño. The rarity of such extreme events and the response of the southeastern Indian Ocean to regional and remote climate forcing are poorly understood owing to the lack of long-term records. Here we use well-replicated coral SST records from within the path of the LC, together with a reconstruction of the El Niño-Southern Oscillation to hindcast historical SST and LC strength from 1795 to 2010. We show that interannual and decadal variations in SST and LC strength characterized the past 215 years and that the most extreme sea level and SST anomalies occurred post 1980. These recent events were unprecedented in severity and are likely aided by accelerated global ocean warming and sea-level rise.
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Antozoos/crecimiento & desarrollo , El Niño Oscilación del Sur/historia , Calentamiento Global/historia , Agua de Mar/química , Movimientos del Agua , Animales , Antozoos/química , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Oceanografía/historia , Temperatura , Australia OccidentalRESUMEN
The Agulhas Current (AC) is the strongest western boundary current in the Southern Hemisphere and is key for weather and climate patterns, both regionally and globally. Its heat transfer into both the midlatitude South Indian Ocean and South Atlantic is of global significance. A new composite coral record (Ifaty and Tulear massive Porites corals), is linked to historical AC sea surface temperature (SST) instrumental data, showing robust correlations. The composite coral SST data start in 1660 and comprise 200 years more than the AC instrumental record. Numerical modelling exhibits that this new coral derived SST record is representative for the wider core region of the AC. AC SSTs variabilities show distinct cooling through the Little Ice Age and warming during the late 18(th), 19th and 20th century, with significant decadal variability superimposed. Furthermore, the AC SSTs are teleconnected with the broad southern Indian and Atlantic Oceans, showing that the AC system is pivotal for inter-ocean heat exchange south of Africa.
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The potential impact of optical fiber sensors embedded into medical textiles for the continuous monitoring of the patient during Magnetic Resonance Imaging (MRI) is presented. In that way, we report on several pure optical sensing technologies for pulse oximetry and respiratory movements monitoring. The technique for pulse oximetry measurement is known as NIRS (Near Infra-Red Spectroscopy) in a reflectance mode. On the other hand, we tested two different optical based designs for the respiratory motions measurements--a macro bending sensor and a Bragg grating sensor, designed to measure the elongation of thoracic and abdominal circumferences during breathing.
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Vestuario , Tecnología de Fibra Óptica/instrumentación , Imagen por Resonancia Magnética/instrumentación , Monitoreo Ambulatorio/instrumentación , Oximetría/instrumentación , Espirometría/instrumentación , Transductores , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
We present a set of Porites coral oxygen isotope records from the tropical and subtropical Western Indian Ocean covering the past 120-336 years. All records were thoroughly validated for proxy response to regional climate factors and their relation to large-scale climate modes. The records show markedly different imprints of regional climate factors. At the same time, all coral records show clear teleconnections between the Western Indian Ocean and the El Nino-Southern Oscillation (ENSO). The multi-proxy site analysis enables the detection of the covariance structure between individual records and climate modes such as ENSO. This method unravels shifts in ENSO teleconnectivity of the Western and Central Indian Ocean on multi-decadal time-scales (after 1976). The Seychelles record shows a stationary correlation with ENSO, Chagos corals show evidence for non-stationary delta18O/ENSO relationships and the Southwestern Indian Ocean corals show a strong relationship with ENSO when the forcing is strong (1880-1920, 1970 to present). Our results indicate that the coral delta18O, in combination with other proxies, can be used to monitor temporal and spatial variations in the sea-surface temperature and the fresh water balance within the Indian Ocean on interannual to interdecadal time-scales.
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Antozoos/metabolismo , Oxígeno/metabolismo , Animales , Antozoos/crecimiento & desarrollo , Atmósfera , Clima , Océano Índico , Isótopos de OxígenoRESUMEN
Pancreatic ductal adenocarcinoma has a median survival of less than 6 months from diagnosis. This is due to the difficulty in early diagnosis, the aggressive biological behaviour of the tumour and a lack of effective therapies for advanced disease. Mammalian heparanase is a heparan-sulphate proteoglycan cleaving enzyme. It helps to degrade the extracellular matrix and basement membranes and is involved in angiogenesis. Degradation of extracellular matrix and basement membranes as well as angiogenesis are key conditions for tumour cell spreading. Therefore, we have analysed the expression of heparanase in human pancreatic cancer tissue and cell lines. Heparanase is expressed in cell lines derived from primary tumours as well as from metastatic sites. By immunohistochemical analysis, it is preferentially expressed at the invading edge of a tumour at both metastatic and primary tumour sites. There is a trend towards heparanase expression in metastasising tumours as compared to locally growing tumours. Postoperative survival correlates inversely with heparanase expression of the tumour reflected by a median survival of 34 and 17 month for heparanase negative and positive tumours, respectively. Our results suggest, that heparanase promotes cancer cell invasion in pancreatic carcinoma and could be used as a prognostic indicator for postoperative survival of patients.
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Adenocarcinoma/diagnóstico , Adenocarcinoma/enzimología , Regulación Neoplásica de la Expresión Génica , Glucuronidasa/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/enzimología , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Western Blotting , Regulación Enzimológica de la Expresión Génica , Glucuronidasa/genética , Células HeLa , Humanos , Inmunohistoquímica , Hibridación in Situ , Metástasis Linfática , Estadificación de Neoplasias , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia , Células Tumorales CultivadasRESUMEN
A nondestructive method to determine viscoelastic properties of gels and fluids involves an oscillating glass fiber serving as a sensor for the viscosity of the surrounding fluid. Extremely small displacements (typically 1-100 nm) are caused by the glass rod oscillating at its resonance frequency. These displacements are analyzed using a phase-sensitive acoustic microscope. Alterations of the elastic modulus of a fluid or gel change the propagation speed of a longitudinal acoustic wave. The system allows to study quantities as small as 10 microliters with temporal resolution >1 Hz. For 2-100 microM f-actin gels a final viscosity of 1.3-9.4 mPa s and a final elastic modulus of 2.229-2.254 GPa (corresponding to 1493-1501 m/s sound velocity) have been determined. For 10- to 100-microM microtubule gels (native, without stabilization by taxol), a final viscosity of 1.5-124 mPa s and a final elastic modulus of 2.288-2. 547 GPa (approximately 1513-1596 m/s) have been determined. During polymerization the sound velocity in low-concentration actin solutions increased up to +1.3 m/s (approximately 1.69 kPa) and decreased up to -7 m/s (approximately 49 kPa) at high actin concentrations. On polymerization of tubulin a concentration-dependent decrease of sound velocity was observed, too (+48 to -12 m/s approximately 2.3-0.1 MPa, for 10- to 100-microM tubulin). This decrease was interpreted by a nematic phase transition of the actin filaments and microtubules with increasing concentration. 2 mM ATP (when compared to 0.2 mM ATP) increased polymerization rate, final viscosity and elastic modulus of f-actin (17 microM). The actin-binding glycolytic enzyme hexokinase also accelerated the polymerization rate and final viscosity but elastic modulus (2.26 GPa) was less than for f-actin polymerized in presence of 0.2 mM ATP (2.28 GPa).