103 research outputs found

    Modelo cinético de los parámetros de oxidación y actividades de la lipasa-lipoxigenasa en aceite de germen de trigo

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    This study aimed to investigate the oxidation profile of wheat germ oil extracted from raw germ during the stabilization with microwave (MW) treatment, and the kinetics of the oxidation parameters (free fatty acids (FFA), peroxide value (PV), thiobarbituric acid (TBA), α-tocopherol, lipase (LA) and lipoxygenase (LOX) enzymes activities) under different storage conditions. For stabilizing raw germ, the MW was treated at 700 W for three minutes. The oxidation parameters for the kinetic modeling were analyzed at different storage times (0, 15, 30, 45, 60,75, 90, and 105. days) and storage temperatures (-18, 0, 4, and 25 °C). The parameters were mathematically modelled and the PV and LA fitted well to the zero-order kinetic model, while FFA with α-tocopherol and TBA followed the first and second-order kinetics, respectively. The kinetic constant (k) was described by an Arrhenius equation and the activation energy ranged from 5.72 to 18.5 kJ/mol for the stabilized germ.Este estudio tuvo como objetivo investigar el perfil de la oxidación del aceite crudo extraído del germen de trigo durante tratamientos de estabilización con microondas (MW), y la cinética de los parámetros de oxidación (ácidos grasos libres (FFA), índice de peróxido (PV), ácido tiobarbitúrico (TBA), actividades de enzimas α-tocoferol, lipasa (LA) y lipoxigenasa (LOX), en diferentes condiciones de almacenamiento. Para estabilizar el germen crudo en MW, se trató a 700 W durante tres minutos. Los parámetros de oxidación para el modelo cinético se analizaron a diferentes tiempos de almacenamiento (0, 15, 30, 45, 60, 75, 90 y 105 días) y temperaturas de almacenamiento (-18, 0, 4 y 25 °C). Los parámetros fueron tratados matemáticamente y el PV y LA se ajustaron bien al modelo cinético de orden cero, mientras que FFA con α-tocoferol y TBA siguieron una cinética de primer y segundo orden, respectivamente. La constante cinética (k) se describió mediante una ecuación de Arrhenius y la energía de activación varió de 5,72 a 18,5 kJ/mol para los gérmenes estabilizados

    Selective Hyper-responsiveness of the Interferon System in Major Depressive Disorders and Depression Induced by Interferon Therapy

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    Though an important percentage of patients with chronic hepatitis C virus (HCV) undergoing interferon (IFN) therapy develop depressive symptoms, the role of the IFN system in the pathogenesis of depressive disorders is not well understood.50 patients with HCV infection were treated with standard combination therapy (pegylated IFN-α2a/ribavirin). IFN-induced gene expression was analyzed to identify genes which are differentially regulated in patients with or without IFN-induced depression. For validation, PBMC from 22 psychiatric patients with a severe depressive episode (SDE) and 11 controls were cultivated in vitro with pegylated IFN-α2a and gene expression was analyzed.IFN-induced depression in HCV patients was associated with selective upregulation of 15 genes, including 6 genes that were previously described to be relevant for major depressive disorders or neuronal development. In addition, increased endogenous IFN-production and selective hyper-responsiveness of these genes to IFN stimulation were observed in SDE patients.Our data suggest that selective hyper-responsiveness to exogenous (IFN therapy) or endogenous (depressive disorders) type I IFNs may lead to the development of depressive symptoms. These data could lead to the discovery of novel therapeutic approaches to treat IFN-induced and major depressive disorders

    Age-dependent motor unit remodelling in human limb muscles.

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    Voluntary control of skeletal muscle enables humans to interact with and manipulate the environment. Lower muscle mass, weakness and poor coordination are common complaints in older age and reduce physical capabilities. Attention has focused on ways of maintaining muscle size and strength by exercise, diet or hormone replacement. Without appropriate neural innervation, however, muscle cannot function. Emerging evidence points to a neural basis of muscle loss. Motor unit number estimates indicate that by age around 71 years, healthy older people have around 40 % fewer motor units. The surviving low- and moderate-threshold motor units recruited for moderate intensity contractions are enlarged by around 50 % and show increased fibre density, presumably due to collateral reinnervation of denervated fibres. Motor unit potentials show increased complexity and the stability of neuromuscular junction transmissions is decreased. The available evidence is limited by a lack of longitudinal studies, relatively small sample sizes, a tendency to examine the small peripheral muscles and relatively few investigations into the consequences of motor unit remodelling for muscle size and control of movements in older age. Loss of motor neurons and remodelling of surviving motor units constitutes the major change in ageing muscles and probably contributes to muscle loss and functional impairments. The deterioration and remodelling of motor units likely imposes constraints on the way in which the central nervous system controls movements

    Fizikalni mehanizmi i metode u tumorskim terapijama i prijenosu lijekova do tumora

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    In addition to several well-known drug delivery strategies developed to facilitate effective chemotherapy with anticancer agents, some new approaches have been recently established, based on specific effects arising from the applications of ultrasound, magnetic and electric fields on drug delivery systems. This paper gives an overview of newly developed methods of drug delivery to tumors and of the related anticancer therapies based on the combined use of different physical methods and specific drug carriers. The conventional strategies and new approaches have been put into perspective to revisit the existing and to propose new directions to overcome the threatening problem of cancer diseases.Osim dobro poznatih metoda prijenosa lijekova u kemoterapijskom pristupu liječenja tumora, nedavno su otkriveni novi načini prijenosa koji se zasnivaju na specifičnim mehanizmima uzrokovanim upotrebom ultrazvuka, magnetskih i električnih polja. Članak sadrži prikaz fizikalnih mehanizama na kojima se temelje ove nove metode, kao i pregled novootkrivenih prijenosnika lijekova (Pluronske micele, magnetoliposomi, magnetski fluidi), novih terapija tumora (magnetska hipertermija, elektrokemoterapija) i najnovijih istraživanja temeljenih na fizikalnom pristupu ovoj problematici

    Ancient pigs reveal a near-complete genomic turnover following their introduction to Europe

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    Archaeological evidence indicates that pig domestication had begun by ∼10,500 y before the present (BP) in the Near East, and mitochondrial DNA (mtDNA) suggests that pigs arrived in Europe alongside farmers ∼8,500 y BP. A few thousand years after the introduction of Near Eastern pigs into Europe, however, their characteristic mtDNA signature disappeared and was replaced by haplotypes associated with European wild boars. This turnover could be accounted for by substantial gene flow from local European wild boars, although it is also possible that European wild boars were domesticated independently without any genetic contribution from the Near East. To test these hypotheses, we obtained mtDNA sequences from 2,099 modern and ancient pig samples and 63 nuclear ancient genomes from Near Eastern and European pigs. Our analyses revealed that European domestic pigs dating from 7,100 to 6,000 y BP possessed both Near Eastern and European nuclear ancestry, while later pigs possessed no more than 4% Near Eastern ancestry, indicating that gene flow from European wild boars resulted in a near-complete disappearance of Near East ancestry. In addition, we demonstrate that a variant at a locus encoding black coat color likely originated in the Near East and persisted in European pigs. Altogether, our results indicate that while pigs were not independently domesticated in Europe, the vast majority of human-mediated selection over the past 5,000 y focused on the genomic fraction derived from the European wild boars, and not on the fraction that was selected by early Neolithic farmers over the first 2,500 y of the domestication process

    Emergence and spread of two SARS-CoV-2 variants of interest in Nigeria.

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    Identifying the dissemination patterns and impacts of a virus of economic or health importance during a pandemic is crucial, as it informs the public on policies for containment in order to reduce the spread of the virus. In this study, we integrated genomic and travel data to investigate the emergence and spread of the SARS-CoV-2 B.1.1.318 and B.1.525 (Eta) variants of interest in Nigeria and the wider Africa region. By integrating travel data and phylogeographic reconstructions, we find that these two variants that arose during the second wave in Nigeria emerged from within Africa, with the B.1.525 from Nigeria, and then spread to other parts of the world. Data from this study show how regional connectivity of Nigeria drove the spread of these variants of interest to surrounding countries and those connected by air-traffic. Our findings demonstrate the power of genomic analysis when combined with mobility and epidemiological data to identify the drivers of transmission, as bidirectional transmission within and between African nations are grossly underestimated as seen in our import risk index estimates
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