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51.
Diabetes affects a large population of the globe and is considered as a leading cause of death. Many synthetic and natural inhibitors have been developed for diabetes treatment. Herein, we report the potential antidiabetic activity of two new heterocyclic systems, namely 3.6-dimethyl-5-oxo-pyrido[3,4f][1,2,4]triazepino[2,3-a]benzimidazole (I) and 10-amino-2-methyl-4-oxo pyrimido[1,2-a]benzimidazole (II) against three related enzymes: α-amylase, α-glucosidase and β-galactosidase. Compounds I and II were synthesized by the action of DMF-DMA and dimethyl sulfate in the presence of water on 2-methyl-3H-benzimidazolo[1,2b][1,2,4]triazepin-4(5H)-one, and are characterized by single X-ray diffraction. The binding interaction modes in the active sites of I and II and targeted enzymes (stable complexes ligand-receptor) are emphasized using the molecular docking approach by applying the Lamarckian genetic algorithm method. Furthermore, plausible mechanisms have been proposed explaining their synthesis. Hirshfeld surface analysis reveals the nature of molecular interactions and fingerprint plots provide information about the percentage contribution from each individual molecular contact to the structure surface.
Graphical abstract Left Molecular packing of 1,4-dimethyl-2-oxo-pyrimido[1,2-a]benzimidazole hydrate. Right Docking active site of α-glucosidase
  相似文献   
52.
To evaluate the efficacy and outcomes of tectonic epikeratoplasty with use of ethanol-preserved corneal grafts for the management of perforated corneal melts. The present retrospective case series includes 10 eyes which underwent tectonic epikeratoplasty for perforated corneal melts. The stromal remainders of Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) graft preparation were stored in 95% ethanol and used as emergency tectonic grafts for restoring globe integrity after sterile and infectious perforated corneal melts. In 6 cases with subtotal corneal melt, DMEK remainders (endothelium-denuded corneoscleral buttons) were used for ‘limbus to limbus’ tectonic epikeratoplasty and in 4 cases DSAEK remainders (anterior stroma) were used to seal focal perforated melts. Graft storage time was 5.1?±?4.9 (ranging from 0.5 to 17) months. The surgeries were successful in all cases with restitution of the globe integrity. During the postoperative course 4 cases developed a graft melt (corneoscleral button for limbus to limbus tectonic epikeratoplasty, n?=?3; lamellar patch, n?=?1) within 2–6 months after the initial procedure. Three patients underwent successful repeat tectonic epikeratoplasty. In the fourth case of graft melt the globe was enucleated due to underlying expulsive haemorrhage and severe pain. The short-term results of the present case series suggest that the use of ethanol-stored stromal remainder of donor corneas after endothelial keratoplasty is an efficient temporary measure for tectonic restoration of perforated corneas.  相似文献   
53.
A relatively unexplored nexus in Drosophila Immune deficiency (IMD) pathway is TGF-beta Activating Kinase 1 (TAK1), which triggers both immunity and apoptosis. In a cell culture screen, we identified that Lysine at position 142 was a K63-linked Ubiquitin acceptor site for TAK1, required for signalling. Moreover, Lysine at position 156 functioned as a K48-linked Ubiquitin acceptor site, also necessary for TAK1 activity. The deubiquitinase Trabid interacted with TAK1, reducing immune signalling output and K63-linked ubiquitination. The three tandem Npl4 Zinc Fingers and the catalytic Cysteine at position 518 were required for Trabid activity. Flies deficient for Trabid had a reduced life span due to chronic activation of IMD both systemically as well as in their gut where homeostasis was disrupted. The TAK1-associated Binding Protein 2 (TAB2) was linked with the TAK1-Trabid interaction through its Zinc finger domain that pacified the TAK1 signal. These results indicate an elaborate and multi-tiered mechanism for regulating TAK1 activity and modulating its immune signal.  相似文献   
54.
Disrupted in schizophrenia 1 (DISC1) is a risk factor for a spectrum of neuropsychiatric illnesses including schizophrenia, bipolar disorder, and major depressive disorder. Here we use two missense Disc1 mouse mutants, described previously with distinct behavioural phenotypes, to demonstrate that Disc1 variation exerts differing effects on the formation of newly generated neurons in the adult hippocampus. Disc1 mice carrying a homozygous Q31L mutation, and displaying depressive-like phenotypes, have fewer proliferating cells while Disc1 mice with a homozygous L100P mutation that induces schizophrenia-like phenotypes, show changes in the generation, placement and maturation of newly generated neurons in the hippocampal dentate gyrus. Our results demonstrate Disc1 allele specific effects in the adult hippocampus, and suggest that the divergence in behavioural phenotypes may in part stem from changes in specific cell populations in the brain.  相似文献   
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Background

The aim of this study was to assess the disease burden of the 2009 pandemic influenza A(H1N1) in Greece.

Methodology/Principal Findings

Data on influenza-like illness (ILI), collected through cross-sectional nationwide telephone surveys of 1,000 households in Greece repeated for 25 consecutive weeks, were combined with data from H1N1 virologic surveillance to estimate the incidence and the clinical attack rate (CAR) of influenza A(H1N1). Alternative definitions of ILI (cough or sore throat and fever>38°C [ILI-38] or fever 37.1–38°C [ILI-37]) were used to estimate the number of symptomatic infections. The infection attack rate (IAR) was approximated using estimates from published studies on the frequency of fever in infected individuals. Data on H1N1 morbidity and mortality were used to estimate ICU admission and case fatality (CFR) rates. The epidemic peaked on week 48/2009 with approximately 750–1,500 new cases/100,000 population per week, depending on ILI-38 or ILI-37 case definition, respectively. By week 6/2010, 7.1%–15.6% of the population in Greece was estimated to be symptomatically infected with H1N1. Children 5–19 years represented the most affected population group (CAR:27%–54%), whereas individuals older than 64 years were the least affected (CAR:0.6%–2.2%). The IAR (95% CI) of influenza A(H1N1) was estimated to be 19.7% (13.3%, 26.1%). Per 1,000 symptomatic cases, based on ILI-38 case definition, 416 attended health services, 108 visited hospital emergency departments and 15 were admitted to hospitals. ICU admission rate and CFR were 37 and 17.5 per 100,000 symptomatic cases or 13.4 and 6.3 per 100,000 infections, respectively.

Conclusions/Significance

Influenza A(H1N1) infected one fifth and caused symptomatic infection in up to 15% of the Greek population. Although individuals older than 65 years were the least affected age group in terms of attack rate, they had 55 and 185 times higher risk of ICU admission and CFR, respectively.  相似文献   
58.
Animals often face complex and changing food environments. While such environments are challenging, an animal should make an association between a food type and its properties (such as the presence of a nutrient or toxin). We use information theory concepts, such as mutual information, to establish a theory for the development of these associations. In this theory, associations are assumed to maximize the mutual information between foods and their consequences. We show that associations are invariably imperfect. An association's accuracy increases with the length of a feeding session and the relative frequency of a food type but decreases as time delay between consumption and postingestive consequence increases. Surprisingly, the accuracy of an association is independent of the number of additional food types in the environment. The rate of information transfer between novel foods and a forager depends on the forager's diet. In light of this theory, an animal's diet may have two competing goals: first, the provision of an appropriate balance of nutrients, and second, the ability to quickly and accurately learn the properties of novel foods. We discuss the ecological and behavioral implications of making associational errors and contrast the timescale and mechanisms of our theory with those of existing theory.  相似文献   
59.

Background

Both host genetic potentials for growth and disease resistance, as well as nutrition are known to affect responses of individuals challenged with micro-parasites, but their interactive effects are difficult to predict from experimental studies alone.

Methodology/Principal Findings

Here, a mathematical model is proposed to explore the hypothesis that a host''s response to pathogen challenge largely depends on the interaction between a host''s genetic capacities for growth or disease resistance and the nutritional environment. As might be expected, the model predicts that if nutritional availability is high, hosts with higher growth capacities will also grow faster under micro-parasitic challenge, and more resistant animals will exhibit a more effective immune response. Growth capacity has little effect on immune response and resistance capacity has little effect on achieved growth. However, the influence of host genetics on phenotypic performance changes drastically if nutrient availability is scarce. In this case achieved growth and immune response depend simultaneously on both capacities for growth and disease resistance. A higher growth capacity (achieved e.g. through genetic selection) would be detrimental for the animal''s ability to cope with pathogens and greater resistance may reduce growth in the short-term.

Significance

Our model can thus explain contradicting outcomes of genetic selection observed in experimental studies and provides the necessary biological background for understanding the influence of selection and/or changes in the nutritional environment on phenotypic growth and immune response.  相似文献   
60.

Background

A trend towards automation of scientific research has recently resulted in what has been termed “data-driven inquiry” in various disciplines, including physics and biology. The automation of many tasks has been identified as a possible future also for the humanities and the social sciences, particularly in those disciplines concerned with the analysis of text, due to the recent availability of millions of books and news articles in digital format. In the social sciences, the analysis of news media is done largely by hand and in a hypothesis-driven fashion: the scholar needs to formulate a very specific assumption about the patterns that might be in the data, and then set out to verify if they are present or not.

Methodology/Principal Findings

In this study, we report what we think is the first large scale content-analysis of cross-linguistic text in the social sciences, by using various artificial intelligence techniques. We analyse 1.3 M news articles in 22 languages detecting a clear structure in the choice of stories covered by the various outlets. This is significantly affected by objective national, geographic, economic and cultural relations among outlets and countries, e.g., outlets from countries sharing strong economic ties are more likely to cover the same stories. We also show that the deviation from average content is significantly correlated with membership to the eurozone, as well as with the year of accession to the EU.

Conclusions/Significance

While independently making a multitude of small editorial decisions, the leading media of the 27 EU countries, over a period of six months, shaped the contents of the EU mediasphere in a way that reflects its deep geographic, economic and cultural relations. Detecting these subtle signals in a statistically rigorous way would be out of the reach of traditional methods. This analysis demonstrates the power of the available methods for significant automation of media content analysis.  相似文献   
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