682 resultados para AW-7020


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Hypochlorite generated in vivo under pathological conditions is a known oxidant and chlorinating agent, able to react with proteins and lipids, which affects the stability of biological membranes. Reaction with unsaturated fatty acyl chains in glycerophospholipids such as phosphatidylcholine results in the formation of chlorohydrins. The aim of this study was to determine the effects of chlorohydrins formed by the reaction of hypochlorite with 1-stearoyl-2-oleoyl-, 1-stearoyl-2-linoleoyl-, and 1-stearoyl-2-arachidonylphosphatidylcholine on biophysical properties of bilayers and their effects on human erythrocytes. Using electrospray mass spectrometry we observed complete conversion of the lipids into chlorohydrins, which resulted in a decrease in the rotational correlation time and an increase in the order parameter of liposomes. Unilamellar chlorohydrin liposomes had a lower permeation coefficient for calcein than liposomes made of parent lipids. Flow cytometry demonstrated fast incorporation of uni and multilamellar chlorohydrin liposomes labeled with NBD-phosphatidylethanolamine into erythrocytes. This effect was accompanied by changes in erythrocyte shape (echinocyte formation) and aggregation. Similar but less pronounced effects were noticed for parent lipids only after longer incubation. Chlorohydrins showed also a stronger hemolytic action, proportional to the lipid:erythrocyte ratio. These results are important for understanding the effects of HOCl on mammalian cells, such as might occur in inflammatory pathology.

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The work reported in this thesis was carried out to contribute to the knowledge of the effects of substrate water availability or water activity (a ) on fungal growth parameters and its implications in the preparationw of materials susceptible to biodeterioration. Fungi were isolated from soils of different ecological sites at a range of substrate aw levels controlled by sodium chloride (NaCl). Three groups of fungi were isolated : firstly, those isolated only at high a (aw about 0.997).secondly, those isolated at high and decreasing aw (aw 0.997 to 0.85) and finally, those isolated at only decreased aw (aw O.95 to 0.80). From these isolations, test fungi were selected to study the effects of pH, temperature, exo-enzyme production and biocide efficacy at decreased aw levels, with glycerol and NaCl as a controlling solutes. The linear extension rates of the fungi increased at all test pH values near optimum a of growth. Test fungi of the Aspergillus glaucus group were found to be most resistant to low aw. Growth and survival of vegetative and fruiting bodies at elevated temperatures were enhanced with the addition of a controlling solutes. A. flavus, A. fumigatus displayed high heat resistance and A. amstelodami, A. versicolor and Penicillium citrinum displayed low heat resistance at high aw levels and vice versa at low aw levels. Amylase, lipase and protease activities were studied at lowered aw , using modifications of the test tube method of Raute11a and Cowling. Amylase and protease production in most xerophilic fungi ceased around 0.80 aw , but lipase production in some xerophilic fungi, including A. glatlcus fungi, was up to and including 0.70 aw with g1ycero1.

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Electrophilic attack of hypochlorous acid on unsaturated bonds of fatty acyl chains is known to result mostly in chlorinated products that show cytotoxicity to some cell lines and were found in biological systems exposed to HOCl. This study aimed to investigate more deeply the products and the mechanism underlying cytotoxicity of phospholipid-HOCl oxidation products, synthesized by the reaction of HOCl with 1-stearoyl-2-oleoyl-, 1-stearoyl-2-linoleoyl-, and 1-stearoyl-2-arachidonyl-phosphatidylcholine. Phospholipid chlorohydrins were found to be the most abundant among obtained products. HOCl-modified lipids were cytotoxic towards HUVEC-ST (endothelial cells), leading to a decrease of mitochondrial potential and an increase in the number of apoptotic cells. These effects were accompanied by an increase of the level of active caspase-3 and caspase-7, while the caspase-3/-7 inhibitor Ac-DEVD-CHO dramatically decreased the number of apoptotic cells. Phospholipid-HOCl oxidation products were shown to affect cell proliferation by a concentration-dependent cell cycle arrest in the G/G phase and activating redox sensitive p38 kinase. The redox imbalance observed in HUVEC-ST cells exposed to modified phosphatidylcholines was accompanied by an increase in ROS level, and a decrease in glutathione content and antioxidant capacity of cell extracts. © 2014 Elsevier Inc. All rights reserved.

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The metabolic rate of organisms may either be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law; or it may be considered a property of the organism that emerges as a result of the organism's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from previous compilations by other authors. Data were read from tables or digitized from graphs. Only measurements made on individuals of know size, or groups of individuals of similar and known size were included. We show that clearance and respiration rates have life-form-dependent allometries that have similar scaling but different elevations, such that the mass-specific rates converge on a rather narrow size-independent range. In contrast, ingestion and growth rates follow a near-universal taxa-independent ~3/4 mass scaling power law. We argue that the declining mass-specific clearance rates with size within taxa is related to the inherent decrease in feeding efficiency of any particular feeding mode. The transitions between feeding mode and simultaneous transitions in clearance and respiration rates may then represent adaptations to the food environment and be the result of the optimization of tradeoffs that allow sufficient feeding and growth rates to balance mortality.

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The Tara Oceans Expedition (2009-2013) sampled the world oceans on board a 36 m long schooner, collecting environmental data and organisms from viruses to planktonic metazoans for later analyses using modern sequencing and state-of-the-art imaging technologies. Tara Oceans Data are particularly suited to study the genetic, morphological and functional diversity of plankton. The present data set includes properties of seawater, particulate matter and dissolved matter from physical, optical and imaging sensors mounted on a vertical sampling system (Rosette) used during the 2009-2013 tara Oceans Expedition. It comprised 2 pairs of conductivity and temperature sensors (SEABIRD components), and a complete set of WEtLabs optical sensors, including chrorophyll and CDOM fluorometers, a 25 cm transmissiometer, and a one-wavelength backscatter meter. In addition, a SATLANTIC ISUS nitrate sensor and a Hydroptic Underwater Vision Profiler (UVP) were mounted on the rosette. In the Arctic Ocean and Arctic Seas (2013), a second oxygen sensor (SBE43) and a four frequency Aquascat acoustic profiler were added. The system was powered on specific Li-Ion batteries and data were self-recorded at 24HZ. Sensors have all been factory calibrated before, during and after the four year program. Oxygen was validated using climatologies (WOA09). Nitrate and Fluorescence data were adjusted with discrete measurements from Niskin bottles mounted on the Rosette, and optical darks were performed monthly on board. A total of 839 quality checked vertical profiles were made during the tara Oceans expedition 2009-2013.

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Instrumentation is a tool of fundamental importance for research in several areas of human knowledge. Research projects are often unfeasible when data cannot be obtained due to lack of instruments, especially due to impor ting difficulties and the high costs there associated. Thus, in order to collaborate with the enhancement of a national technology, a multiband hand - held sun p hotometer (FSM - 4) was developed to operate in the 500 nm, 670 nm, 870 nm and 940 nm bands. In the 500 nm, 670 nm and 870 nm bands aerosols are monitored for evaluation of the AOD (Aerosol Optical Depth), and the PWC (Precipitable Water Column) is evaluated in the 940 nm band. For the development of the mech anical and electronic parts for the FSM - 4, th e materials and componen ts should combine low cost and quality of the data collected. The calibration process utilized the Langley method (ML) and Modified Langley Method (MLM). These methods are usually applied at high altitudes in order to provide atmosp heric optical stability. This condition however can be found in low height sites as shown in the research by Liu et al. (2010). Thus, for calibration of the FSM - 4, we investigated the atmospher ic optical stability utilizing the ML and MLM at a site in the cit y of Caicó / RN, located in the s emiarid region in northeastern Brazil. This site lies in a region far aw ay from large urban centers and activities generating anthropogenic atmospheric pollution. Data for calibration of the prototype were collected usin g the FSM - 4 in two separate operations during the dry season, one in December 2012 and another in September 2013. The methodologies showed optical atmospheric instability in the studied region through the dispersion of the values obtained for the calibrati on constant. This dispersion is affected by the variability of AOD and PWC during the appl ication of the above mentioned methods . As an alternative to the descr ibed sun photometer calibration , a short study was performed using the sun photometer worldwide network AERONET/NASA (AERsol RObotic NETwork – US Space Agency), installed in Petrolina / PE in Brazil. Data were collected for three days utilizing the AERONET instruments and the FSM - 4, operating simultaneously on the same site. By way of the ML and MLM techniques, convergent test values were obtained for the calibration constants, despite the low amount of data collected. This calibration transfer methodology proved to be a viable alternative to the FSM - 4 calibration .

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The objective of this study was to evaluate the effects of the use of cashew bagasse bran (CBB) as food ingredient in qualitative feed restriction programs on the carcass traits, meat quality, organs weight and intestinal morphometry of barrows and gilts. Twenty – four crossbred pigs were used (12 barrows and 12 gilts) with an average initial body weight of 57.93 ± 3.67 kg/LW. The experimental designs was in randomized blocks 3x2 factorial arrangement with three level (0%, 15% e 30% CBB), two genders (barrows and gilts) and four repetition. A total of twenty-four instalments. The treatments were composed of basal diet (BD) formulated with corn, soybean meal and commercial base mix for finishing pigs, being containing different levels of CBB. At the end of the trial period the animals were slaughtered for the evaluation of the meat quality, traits carcass, Absolute Weight (AW) and Relative Weight (RW) of the organs and morphometric study of small intestine fragment. The inclusion of (CBB) in the diets did not affect the traits carcass of gilts, but interfered in the traits carcass of the barrow positively, increasing the yield of meat into cold carcass and reducing the thickness of subcutaneous fat, without affecting the fatty acid profile. However, we observed increased weight of organs and partial volume of absortiva mucosa of gilts. In the comparison between sex was observed a greater liver weight (AW) and (RW), and surface density of absortiva mucosa of barrow. The use of CBB was considered as ingredient to be used in programs of qualitative feed restriction for finishing pigs.

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The objective of this study was to evaluate the effects of the use of cashew bagasse bran (CBB) as food ingredient in qualitative feed restriction programs on the carcass traits, meat quality, organs weight and intestinal morphometry of barrows and gilts. Twenty – four crossbred pigs were used (12 barrows and 12 gilts) with an average initial body weight of 57.93 ± 3.67 kg/LW. The experimental designs was in randomized blocks 3x2 factorial arrangement with three level (0%, 15% e 30% CBB), two genders (barrows and gilts) and four repetition. A total of twenty-four instalments. The treatments were composed of basal diet (BD) formulated with corn, soybean meal and commercial base mix for finishing pigs, being containing different levels of CBB. At the end of the trial period the animals were slaughtered for the evaluation of the meat quality, traits carcass, Absolute Weight (AW) and Relative Weight (RW) of the organs and morphometric study of small intestine fragment. The inclusion of (CBB) in the diets did not affect the traits carcass of gilts, but interfered in the traits carcass of the barrow positively, increasing the yield of meat into cold carcass and reducing the thickness of subcutaneous fat, without affecting the fatty acid profile. However, we observed increased weight of organs and partial volume of absortiva mucosa of gilts. In the comparison between sex was observed a greater liver weight (AW) and (RW), and surface density of absortiva mucosa of barrow. The use of CBB was considered as ingredient to be used in programs of qualitative feed restriction for finishing pigs.

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Site 619, located in the Pigmy Basin off the coast of Louisiana, penetrated the late Quaternary Ericson Zones X, Y, and Z. The penetrated section can be divided into four intervals. The lower interval (below 157 m sub-bottom) comprises 51 m of displaced sediments which probably originated from the Louisiana continental shelf. The upper three intervals (above 157 m) are dominated by pelagic/hemipelagic sedimentation associated with a closed basin. These are divided on the basis of planktonic foraminifers into Zones X, Y, and Z. These warm-cool water intervals are identified mainly by using the Globorotalia menardii complex (warm) and G. inflata (cool). The intervals correlate with published curves taken from piston core samples in the western Gulf of Mexico.

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Acknowledgements The authors are grateful to Junta de Comunidades de Castilla-La Mancha (PCC-05-004-2, PAI06-0094, PCI-08-0096, PEII09-0032-5329) and the Ministerio de Economía y Competitividad (CTQ2013-48411-P) for financial support. M.J. Patiño Ropero acknowledges the Junta de Comunidades de Castilla-La Mancha for her PhD. fellowship.

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Funded by UK's Biotechnology and Biological Sciences Research Council (BBSRC) Department for Environment, Food and Rural Affairs (DEFRA). Grant Number: LK0863 BBSRC strategic programme Grant on Energy Grasses & Bio-refining. Grant Number: BBS/E/W/10963A01 OPTIMISC. Grant Number: FP7-289159 WATBIO. Grant Number: FP7-311929 Innovate UK/BBSRC ‘MUST’. Grant Number: BB/N016149/1

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O chá é a bebida mais consumida no mundo depois da água, no entanto, é no continente Asiático que é mais consumido. Existem vários tipos diferentes de chá “descendentes” da planta Camellia sinensis. É uma bebida multifacetada e benéfica para o próprio consumidor, devido às suas propriedades organoléticas e propriedades benéficas para a saúde (presença de antioxidantes). Hoje em dia existe uma crescente procura por produtos inovadores, de elevada qualidade nutricional, nomeadamente produtos alimentares com propriedades diuréticas ou dietéticas. Por outro lado, os organismos marinhos têm-se revelado como fonte de compostos bioativos com elevado potencial. Nomeadamente as algas que têm demonstrado produzir moléculas, pelo seu metabolismo secundário, com aplicação alimentar, farmacológica, entre outras. Desta forma, o principal objetivo do trabalho foi avaliar a capacidade da alga Fucus Spiralis, uma alga edível com elevado poder antioxidante, na transferência de antioxidantes durante a preparação de uma tisana, para o desenvolvimento de uma bebida inovadora “chá de alga”. Por outro lado, este trabalho teve também como objetivo fazer uma nova tisana “variante” do chá verde alga Fucus Spiralis. De modo a estudar o melhor processo para a secagem da alga, esta foi seca através de três métodos: liofilização, em estufa e no secador Tray-drier. Para os três métodos foram avaliados vários parâmetros químicos, como a quantificação de polifenóis totais, cor, aW e teor de humidade. As análises foram realizadas logo após a secagem. Ao longo do tempo (60 dias), foi também medido a quantificação de polifenóis com a alga embalada a vácuo e sem estar embalada a vácuo. Finalmente, adicionando a alga, o chá verde e aditivos alimentares, procederam-se a três diferentes processos de conservação: esterilização, pasteurização e filtração (filtro 0,22μm). Após estes tratamentos foi realizado um estudo microbiológico, a variação de cor e a quantificação de polifenóis totais ao longo de 30 dias. O menor valor obtido de aW foi observado para a alga liofilizada. Por outro lado os menores valores de humidade foram obtidos pela secagem por liofilização e pela utilização da estufa ventilada. A realização da tisana de Fucus spiralis revelou a libertação de antioxidantes em todos os processos de secagem e para todas as concentrações testadas (0,1g; 0,5g e 1g/300mL). No entanto, a libertação de polifenóis revelou-se apenas dependente do processo de secagem para a concentração de 0,5 g/300 mL, onde a quantificação total de polifenóis foi superior para o processo de liofilização (0,246 ± 0,049 mg equivalentes de ácido gálico/mL). Este valor não apresentou diferenças estatisticamente significativas com os polifenóis quantificados para a concentração de 1g/300mL. O armazenamento da alga Fucus spiralis ao longo de 60 dias em vácuo ou na ausência de vácuo não provocaram alterações na quantificação total de polifenóis e foi independente do processo de secagem. Durante os 60 dias ocorreu uma diminuição dependente do tempo dos polifenóis libertados para a tisana de alga. Esta diminuição foi particularmente acentuada até aos 15 dias. A formulação de uma tisana com 0,5g da alga Fucus spiralis e 0,5g de chá verde revelou-se, tendencialmente, com maior concentração de polifenóis de que uma tisana com 1 g de chá verde ou 1 g. Para a tisana com 0,5g da alga Fucus spiralis e 0,5g de chá verde o processo de esterilização e pasteurização não impediram o crescimento de microrganismo ao final de 30 dias de armazenamento da tisana. Contrariamente, o processo de filtração garantiu ausência de carga bacteriana durante os 30 dias de armazenamento. Por outro lado os níveis de polifenóis diminuíram ligeiramente ao longo do tempo de armazenamento, mas de um modo independente do processo de conservação. Desta forma, as tisanas de alga (Fucus spiralis) e chá verde desenvolvidas no presente trabalho, quando liofilizadas e filtradas, apresentaram um elevado potencial antioxidante, apresentando-se como um produto inovador para a indústria alimentar.

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Background.  The optimum approach for infectious complication surveillance for cardiac implantable electronic device (CIED) procedures is unclear. We created an automated surveillance tool for infectious complications after CIED procedures. Methods.  Adults having CIED procedures between January 1, 2005 and December 31, 2011 at Duke University Hospital were identified retrospectively using International Classification of Diseases, 9th revision (ICD-9) procedure codes. Potential infections were identified with combinations of ICD-9 diagnosis codes and microbiology data for 365 days postprocedure. All microbiology-identified and a subset of ICD-9 code-identified possible cases, as well as a subset of procedures without microbiology or ICD-9 codes, were reviewed. Test performance characteristics for specific queries were calculated. Results.  Overall, 6097 patients had 7137 procedures. Of these, 1686 procedures with potential infectious complications were identified: 174 by both ICD-9 code and microbiology, 14 only by microbiology, and 1498 only by ICD-9 criteria. We reviewed 558 potential cases, including all 188 microbiology-identified cases, 250 randomly selected ICD-9 cases, and 120 with neither. Overall, 65 unique infections were identified, including 5 of 250 reviewed cases identified only by ICD-9 codes. Queries that included microbiology data and ICD-9 code 996.61 had good overall test performance, with sensitivities of approximately 90% and specificities of approximately 80%. Queries with ICD-9 codes alone had poor specificity. Extrapolation of reviewed infectious rates to nonreviewed cases yields an estimated rate of infection of 1.3%. Conclusions.  Electronic queries with combinations of ICD-9 codes and microbiologic data can be created and have good test performance characteristics for identifying likely infectious complications of CIED procedures.

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Atlantic killifish (Fundulus heteroclitus) inhabiting the Atlantic Wood Industries region of the Elizabeth River, Virginia, have passed polycyclic aromatic hydrocarbon (PAH) resistance to their offspring as evidenced by early life stage testing of developmental toxicity after exposure to specific PAHs. Our study focused on environmentally relevant PAH mixtures in the form of Elizabeth River sediment extract (ERSE). Juvenile (5 month) F1 progeny of pollution-adapted Atlantic Wood (AW) parents and of reference site (King's Creek [KC]) parents were exposed as embryos to ERSE. Liver alterations, including nonneoplastic lesions and microvesicular vacuolation, were observed in both populations. ERSE-exposed KC fish developed significantly more alterations than unexposed KC fish. Interestingly, unexposed AW killifish developed significantly more alterations than unexposed KC individuals, suggesting that AW juveniles are not fully protected from liver disease; rapid growth of juvenile fish may also be an accelerating factor for tumorigenesis. Because recent reports show hepatic tumor formation in adult AW fish, the differing responses from the 2 populations provided a way to determine whether embryo toxicity protection extends to juveniles. Future investigations will analyze older life stages of killifish to determine differences in responses related to chronic disease.