279 research outputs found

    Arginase I in myeloid suppressor cells is induced by COX-2 in lung carcinoma

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    Myeloid suppressor cells (MSCs) producing high levels of arginase I block T cell function by depleting l-arginine in cancer, chronic infections, and trauma patients. In cancer, MSCs infiltrating tumors and in circulation are an important mechanism for tumor evasion and impair the therapeutic potential of cancer immunotherapies. However, the mechanisms that induce arginase I in MSCs in cancer are unknown. Using the 3LL mouse lung carcinoma, we aimed to characterize these mechanisms. Arginase I expression was independent of T cell–produced cytokines. Instead, tumor-derived soluble factors resistant to proteases induced and maintained arginase I expression in MSCs. 3LL tumor cells constitutively express cyclooxygenase (COX)-1 and COX-2 and produce high levels of PGE2. Genetic and pharmacological inhibition of COX-2, but not COX-1, blocked arginase I induction in vitro and in vivo. Signaling through the PGE2 receptor E-prostanoid 4 expressed in MSCs induced arginase I. Furthermore, blocking arginase I expression using COX-2 inhibitors elicited a lymphocyte-mediated antitumor response. These results demonstrate a new pathway of prostaglandin-induced immune dysfunction and provide a novel mechanism that can help explain the cancer prevention effects of COX-2 inhibitors. Furthermore, an addition of arginase I represents a clinical approach to enhance the therapeutic potential of cancer immunotherapies

    Novel effects of strains in graphene and other two dimensional materials

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    The analysis of the electronic properties of strained or lattice deformed graphene combines ideas from classical condensed matter physics, soft matter, and geometrical aspects of quantum field theory (QFT) in curved spaces. Recent theoretical and experimental work shows the influence of strains in many properties of graphene not considered before, such as electronic transport, spin-orbit coupling, the formation of Moir\'e patterns, optics, ... There is also significant evidence of anharmonic effects, which can modify the structural properties of graphene. These phenomena are not restricted to graphene, and they are being intensively studied in other two dimensional materials, such as the metallic dichalcogenides. We review here recent developments related to the role of strains in the structural and electronic properties of graphene and other two dimensional compounds.Comment: 75 pages, 15 figures, review articl

    Humoral immune response in hens naturally infected with Salmonella Enteritidis against outer membrane proteins and other surface structural antigens

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    A simple procedure for obtaining surface exposed antigens of Salmonella Enteritidis is described. A heat treatment of whole bacteria in saline solution induced the release of small membrane vesicles containing outer membrane components as well as surface appendage components, such as fimbriae and flagellin. The characterization of the structural components of this extract, called HE, was established by SDS-PAGE and immunoblotting using polyclonal and monoclonal specific antibodies. Five major groups of proteins were identified: flagellin, porins, OmpA, SEF21 and SEF14 fimbriae. The immunogenicity of these proteins was studied by immunoblotting with serum samples from naturally infected hens. Flagellin, porins, OmpA, SEF14 and SEF21 fimbriae were immunogenic in the S. Enteritidis infected hens (frequency of reactants: 47.3, 97.3, 64.7, 50.0 and 60.8%, respectively); porins also reacted with sera from non infected hens (66.7%). The immunogenicity of these antigens in infected birds provide promise that they may serve as components of an effective subcellular vaccine for poultry salmonellosis

    Cathodoluminescence Characterization of Dilute Nitride GaNSbAs Alloys

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    The effects of ex situ annealing in N ambient and in situ annealing in As ambient on GaNSbAs/GaAs structures grown by molecular beam epitaxy were investigated by low temperature cross-sectional cathodoluminescence (CL). The amount and distribution of Sb was measured by energy dispersive spectroscopy (EDS). The cross-sectional CL analysis of all samples reveals a shift of the near band edge (NBE) emission along the growth axis, presumably associated with a non-uniform incorporation of Sb during the growth process, in agreement with the Sb distribution measured by EDS in the as-grown sample. The NBE emission in the annealed samples presents a redshift with respect to the as-grown sample. This effect might be explained by a redistribution/activation of N in the GaNSbAs lattice since the Sb distribution measured by EDS does not reveal significant changes, within the error margin, with respect to the as-grown sample. The in situ annealed in the As overpressure sample shows the best properties for solar cells applications, i.e., a NBE peak position close to 1.0 eV and the lowest full width at half maximum of this emission.Spanish Government (MINECO Project ENE2014- 56069-C4-4-R) and Junta de Castilla y Leo´n (VA293U13 and VA081U16 Projects). The Ministry of Economy and Competitiveness MINECO supports this work through Projects TEC2014-54260- C3-1-P, TEC2014-54260-C3-2-P, TEC2014-54260- C3-3-P, PCIN-2015-181-C02-01 and PCIN-2015- 181-C02-02

    Impacto de "El Niño 1997-98" sobre el ecosistema marino somero de la costa central del Perú

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    The characteristics of intensity, and untimely of "El Niño 1997-98" answer, manifested by superficial phytoplankton, rocky shore macroalgae, and soft bottom macrobenthos were analyzed from December 1996 to August 1998 in Ancon Bay (11 °46' LS and 77°11' LW). A significative increase of both, temperature since April (17,4°C), and oxygen (2,46 mLL-1)from May 1997 in the bottom of the study area, characterized this event. In superficial phytoplankton, the presence of indicator species of warm oceanic water, and an unusual increase of both dinoflagellate and microflagellate density at the beginning of April 1997 were recorded since January. The density of Chondracanthus chamissoi population reached 2684 ind.x32 m ' of shoreline in October 1997, and the proportion 01 gametophytes increased during 1998. The density and species number 01 soft bottom macrobenthos reached maximum values of 90 indo x 0,04 m-2, and 20 species in June, and November 1997 respectively; these variations have a good correlation with intensity changes of "El Niño". The biomass reached its maximum value 0,55 g pssc x 0,04 m-2 in January 1998. Finally, it is showed that "El Niño 1997-98" biological impact was lesser than that of 1982-83 however the similarity of intensity in both events; and that shallow water showed early and reliable indicators of "El Niño", in both, the phytoplankton as in the benthos. Moreover, the presence of a post-Niño period showed that "El Niño" impact on population and communities might be complex.Se analizó las características de intensidad y precocidad de las respuestas a "El Niño 1997-98" manifestada por el fitoplancton superficial, macroalgas de la orilla rocosa y macrobentos de fondo blando en la Bahía de Ancón (11º46' LS y 77211' LW), entre diciembre de 1996 y agosto de 1998. Este evento se caracterizó por un incremento significativo de la temperatura desde abril (17,4ºC) y del oxígeno (2,46 mi x l") a partir de mayo de 1997, en los fondos del área de estudio. En el fitoplancton superficial se registró la presencia de especies indicadoras de aguas oceánicas cálidas desde enero y un inusual aumento en la densidad de dinoflagelados y microflagelados a inicios de abril de 1997. La densidad de la población de la macroalga Chondracanthus chamissoi alcanzó 2 684 indo x 32 m' de línea de orilla en octubre de 1997, y la proporción de gametofitos se incrementó durante 1998. La densidad y el número de especies del macrobentos de fondo blando alcanzaron los valores máximos de 90 indo x 0,04 m•2 y 20 especies en junio y noviembre de 1997, respectivamente; estas variaciones correlacionaron bien con los cambios en la intensidad de "El Niño". La biomasa llegó a su máximo valor de 0,55 g pssc x 0,04 m•2 recién en enero de 1998. Finalmente, se demuestra que el impacto biológico de "El Niño 1997-98" fue menor al del evento de 1982-83, no obstante la similitud en la intensidad de ambos eventos; y que las aguas someras presentaron indicadores tempranos y confiables de "El Niño", tanto en el fitoplancton como en el bentos. Además, la presencia de un período post-Niño demuestra que el impacto de "El Niño" sobre las poblaciones y comunidades puede ser complejo

    Diagnostic role of new Doppler index in assessment of renal artery stenosis

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    BACKGROUND: Renal artery stenosis (RAS) is one of the main causes of secondary systemic arterial hypertension. Several non-invasive diagnostic methods for RAS have been used in hypertensive patients, such as color Doppler ultrasound (US). The aim of this study was to assess the sensitivity and specificity of a new renal Doppler US direct-method parameter: the renal-renal ratio (RRR), and compare with the sensitivity and specificity of direct-method conventional parameters: renal peak systolic velocity (RPSV) and renal aortic ratio (RAR), for the diagnosis of severe RAS. METHODS: Our study group included 34 patients with severe arterial hypertension (21 males and 13 females), mean age 54 (± 8.92) years old consecutively evaluated by renal color Doppler ultrasound (US) for significant RAS diagnosis. All of them underwent digital subtraction arteriography (DSA). RAS was significant if a diameter reduction > 50% was found. The parameters measured were: RPSV, RAR and RRR. The RRR was defined as the ratio between RPSV at the proximal or mid segment of the renal artery and RPSV measured at the distal segment of the renal artery. The sensitivity and specificity cutoff for the new RRR was calculated and compared with the sensitivity and specificity of RPSV and RAR. RESULTS: The accuracy of the direct method parameters for significant RAS were: RPSV >200 cm/s with 97% sensitivity, 72% specificity, 81% positive predictive value and 95% negative predictive value; RAR >3 with 77% sensitivity, 90% specificity, 90% positive predictive value and 76% negative predictive value. The optimal sensitivity and specificity cutoff for the new RRR was >2.7 with 97% sensitivity (p < 0.004) and 96% specificity (p < 0.02), with 97% positive predictive value and 97% negative predictive value. CONCLUSION: The new RRR has improved specificity compared with the direct method conventional parameters (RPSV >200cm/s and RAR >3). Both RRR and RPSV show better sensitivity than RAR for the RAS diagnosis

    Surface indicators are correlated with soil multifunctionality in global drylands

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    Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field-based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world-wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost-effective monitoring of soil multifunctionality under changing land-use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world-wide.Fil: Eldridge, David J.. University of New South Wales; AustraliaFil: Delgado Baquerizo, Manuel. Universidad Rey Juan Carlos; EspañaFil: Quero, José L.. Universidad de Córdoba; EspañaFil: Ochoa, Victoria. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: Gozalo, Beatriz. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: García Palacios, Pablo. Universidad Rey Juan Carlos; EspañaFil: Escolar, Cristina. Universidad Rey Juan Carlos; EspañaFil: García Gómez, Miguel. Universidad Politécnica de Madrid; EspañaFil: Prina, Aníbal. Universidad Nacional de La Pampa; ArgentinaFil: Bowker, Mathew A.. Northern Arizona University; Estados UnidosFil: Bran, Donaldo Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; ArgentinaFil: Castro, Ignacio. Universidad Experimental Simón Rodríguez; VenezuelaFil: Cea, Alex. Universidad de La Serena; ChileFil: Derak, Mchich. No especifíca;Fil: Espinosa, Carlos I.. Universidad Técnica Particular de Loja; EcuadorFil: Florentino, Adriana. Universidad Central de Venezuela; VenezuelaFil: Gaitán, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Suelos; Argentina. Universidad Nacional de Luján. Departamento de Tecnología; ArgentinaFil: Gatica, Mario Gabriel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Gómez González, Susana. Universidad de Cádiz; EspañaFil: Ghiloufi, Wahida. Université de Sfax; TúnezFil: Gutierrez, Julio R.. Universidad de La Serena; ChileFil: Guzman, Elizabeth. Universidad Técnica Particular de Loja; EcuadorFil: Hernández, Rosa M.. Universidad Experimental Simón Rodríguez; VenezuelaFil: Hughes, Frederic M.. Universidade Estadual de Feira de Santana; BrasilFil: Muiño, Walter. Universidad Nacional de La Pampa; ArgentinaFil: Monerris, Jorge. No especifíca;Fil: Ospina, Abelardo. Universidad Central de Venezuela; VenezuelaFil: Ramírez, David A.. International Potato Centre; PerúFil: Ribas Fernandez, Yanina Antonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Romão, Roberto L.. Universidade Estadual de Feira de Santana; BrasilFil: Torres Díaz, Cristian. Universidad del Bio Bio; ChileFil: Koen, Terrance B.. No especifíca;Fil: Maestre, Fernando T.. Universidad Rey Juan Carlos; España. Universidad de Alicante; Españ

    Malignant melanoma arising from a perianal fistula and harbouring a BRAF gene mutation: a case report

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    <p>Abstract</p> <p>Background</p> <p>Melanoma of the anal region is a very uncommon disease, accounting for only 0.2-0.3% of all melanoma cases. Mutations of the <it>BRAF </it>gene are usually absent in melanomas occurring in this region as well as in other sun-protected regions. The development of a tumour in a longstanding perianal fistula is also extremely rare. More frequent is the case of a tumour presenting as a fistula, that is, the fistula being a consequence of the cancerous process, although we have found only two cases of fistula-generating melanomas reported in the literature.</p> <p>Case Presentation</p> <p>Here we report the case of a 38-year-old male who presented with a perianal fistula of four years of evolution. Histopathological examination of the fistulous tract confirmed the presence of malignant melanoma. Due to the small size and the central location of the melanoma inside the fistulous tract, we believe the melanoma reported here developed in the epithelium of the fistula once the latter was already formed. Resected sentinel lymph nodes were negative and the patient, after going through a wide local excision, remains disease-free nine years after diagnosis. DNA obtained from melanoma tissue was analysed by automated direct sequencing and the <it>V600E </it>(<it>T1799A</it>) mutation was detected in exon 15 of the <it>BRAF </it>gene.</p> <p>Conclusion</p> <p>Since fistulae experience persistent inflammation, the fact that this melanoma harbours a <it>BRAF </it>mutation strengthens the view that oxidative stress caused by inflammatory processes plays an important role in the genesis of <it>BRAF </it>gene mutations.</p
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