42 research outputs found

    Expression of insulin pathway genes during the period of caste determination in the honey bee, Apis mellifera

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    Female honeybees have two castes, queens and workers. Developmental fate is determined by larval diet. Coding sequences made available through the Honey Bee Genome Sequencing Consortium allow for a pathway-based approach to understanding caste determination. We examined the expression of several genes of the insulin signalling pathway, which is central to regulation of growth based on nutrition. We found one insulin-like peptide expressed at very high levels in queen but not worker larvae. Also, the gene for an insulin receptor was expressed at higher levels in queen larvae during the 2nd larval instar. These results demonstrate that the insulin pathway is a compelling candidate for pursing the relationship between diet and downstream signals involved in caste determination and differentiation

    АКСИОЛОГИЧЕСКИЕ ТРАНСФОРМАЦИИ В ГЛОБАЛЬНОМ ОБРАЗОВАНИИ КАК СЛЕДСТВИЕ ИНФОРМАЦИОННЫХ ТЕХНОЛОГИЙ

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    The article focuses on the problems of national education at the current moment. The authors make case about the outlooks of improving the quality of education based on the most technologies. The authors outline that application of information technologies enhances the quality of training of specialists taking into account the obvious fact that social institutions have a high degree of originality and uniqueness and require development of specific technologies for each of them. Full socio-philosophical analysis of the role of information in global education implies investigation of the peculiarities of education as a part of society. The thing is that research devoted to the role, place and outlooks would depend on solution of social problems, education problems as an important social institute. This means that any actions on directing the information flows in education should follow the national idea, as the education system becomes a reason and a consequence of all social transformations. In other words, the education system is closely connected with sustainability of society; however, it has its own peculiarity specified by concrete education activity. Modern global education differs from the traditional one (Soviet), in the way knowledge is delivered on the broader spectrum. The authors pay attention to the mechanism of knowledge delivering and qualitative characteristics of new information that should become the bridge to the new knowledge by means of application new ways of information transmission. Due to the fact that information technologies are widely applied, teachers should deliver knowledge not only by means of classroom studies but using university and global information nets.В статье рассматриваются вопросы отечественного образования на современном этапе. Раскрываются перспективы повышения качества образования на основе новейших технологий. При этом доказывается, что внедрение информационных технологий является мощным средством повышения качества подготовки специалистов с учетом того очевидного обстоятельства, что социальные институты обладают высокой степенью неповторимости и уникальности и требуют разработки специфических технологий применительно к каждому из них. Полноценный социально-философский анализ роли информации в глобальном образовании предполагает исследование особенностей самого образования как части социума. Дело в том, что любые исследования, посвященные роли, месту и перспективам информации, так или иначе будут зависеть от уровня решения социальных проблем вообще и образования как важнейшего социального института в частности. Это означает, что любые действия по направлению потоков информации в образовательном процессе должны согласовываться с общенациональной идеей, поскольку система образования всегда является и причиной, и следствием всех социальных трансформаций. Другими словами, образовательная система тесным образом связана с устойчивостью всего общества, однако имеет свою особенность, детерминированную спецификой конкретной образовательной деятельности. Современная глобальная школа отличается от традиционной, советской, в частности тем, что трансляция знаний ведется по более широкому спектру. Представляет интерес как сам механизм трансляции знаний, так и качественные характеристики новой информации, которая должна стать своеобразным мостиком в новое знание, используя в обучении новые каналы передачи информации. В условиях активного применения информационных технологий наряду с традиционными авторскими программами преподаватели могут и должны доносить знания не только посредством аудиторных занятий, но и путем использования как локальных (вузовских), так и глобальных информационных сетей

    Primjena tehnologije rekombinantne DNA za pripravke kolinesteraza kao antidota i detektora organofosfata

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    To develop new avenues for synthesizing novel antidotes for organophosphate poisoning and for detection of the organophosphates, we have turned to recombinant DNA methods to synthesize cholinesterases with unusual properties. For antidotal therapy we describe mutations of the native mouse and human enzymes that allow for enhanced rates of oxime reactivation. Such enzymes, when localized in the circulation, would enable the circulating cholinesterase to become a catalytic rather than simply a stoichiometric scavenger. Hence, “oxime-assisted catalysis” provides a means for scavenging the organophosphates in the circulation thereby minimizing their tissue penetration and toxicity. Accordingly, the oxime antidote or prophylactic agent has a dual action within the circulation and at the tissue level. Second, through a novel chemistry, termed freeze-frame, click chemistry, we have used organophosphate conjugates of acetylcholinesterase as templates for the synthesis of novel nucleophilic reactivating agents. Finally, acetylcholinesterase can be modified through cysteine substitution mutagenesis and attachment of fluorophores at the substitution positions. When linked at certain locations in the molecule, the attached fluorophore is sensitive to organophosphate conjugation with acetylcholinesterase, and thus the very target of insecticide or nerve agent action becomes a detection molecule for organophosphate exposure.Razvijajući novi pristup sintezi antidota pri otrovanju organofosfatima kao i njihovu detekciju, primijenili smo metode rekombinantne DNA za pripremu kolinesteraza s neuobičajenim svojstvima. Za antidotsku terapiju istražili smo mutacije prirodnih enzima miša i čovjeka koje povećavaju brzine reaktivacije oksimom. Takvi enzimi bi po unosu u cirkulaciju postali katalitički, a ne samo stehiometrijski odstranjivači organofosfata. Na taj način “oksimom potpomognuta kataliza” omogućava čišćenje organofosfata iz cirkulacije umanjujući prodiranje organofosfata u tkiva i njihovu toksičnost. Prema tome, oksim kao antidot ima dvojaku ulogu: u cirkulaciji i na razini tkiva. S druge strane, uporabom novog sintetskog pristupa u oblikovanju biološki aktivnih spojeva poznatog kao “klik kemija” diskretnih proteinskih konformacija, organofosforilirani konjugati acetilkolinesteraze služe kao kalup u sintezi novih nukleofilnih reaktivatora. Naposljetku, acetilkolinesteraza se može mutagenezom modificirati uvo|enjem cisteina na koje se mogu vezati fluorofori. Fluorofori uvedeni na određena mjesta u molekuli acetilkolinesteraze mijenjaju svoja fluorescentna svojstva pri konjugaciji organofosfata s enzimom koji na taj način od objekta djelovanja insekticida i živčanih bojnih otrova postaje molekula za detekciju izloženosti organofosfatima

    Queen mandibular pheromone: questions that remain to be resolved

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    The discovery of ‘queen substance’, and the subsequent identification and synthesis of keycomponents of queen mandibular pheromone, has been of significant importance to beekeepers and to thebeekeeping industry. Fifty years on, there is greater appreciation of the importance and complexity of queenpheromones, but many mysteries remain about the mechanisms through which pheromones operate. Thediscovery of sex pheromone communication in moths occurred within the same time period, but in this case,intense pressure to find better means of pest management resulted in a remarkable focusing of research activityon understanding pheromone detection mechanisms and the central processing of pheromone signals in themoth. We can benefit from this work and here, studies on moths are used to highlight some of the gaps in ourknowledge of pheromone communication in bees. A better understanding of pheromone communication inhoney bees promises improved strategies for the successful management of these extraordinary animals

    Comprehensive analysis of epigenetic clocks reveals associations between disproportionate biological ageing and hippocampal volume

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    The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised measures of age acceleration, based on DNA methylation patterns (DNAm age), and cross-sectional and longitudinal cognition and AD-related neuroimaging phenotypes (volumetric MRI and Amyloid-β PET) in the Australian Imaging, Biomarkers and Lifestyle (AIBL) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Significant associations were observed between age acceleration using the Hannum epigenetic clock and cross-sectional hippocampal volume in AIBL and replicated in ADNI. In AIBL, several other findings were observed cross-sectionally, including a significant association between hippocampal volume and the Hannum and Phenoage epigenetic clocks. Further, significant associations were also observed between hippocampal volume and the Zhang and Phenoage epigenetic clocks within Amyloid-β positive individuals. However, these were not validated within the ADNI cohort. No associations between age acceleration and other Alzheimer’s disease-related phenotypes, including measures of cognition or brain Amyloid-β burden, were observed, and there was no association with longitudinal change in any phenotype. This study presents a link between age acceleration, as determined using DNA methylation, and hippocampal volume that was statistically significant across two highly characterised cohorts. The results presented in this study contribute to a growing literature that supports the role of epigenetic modifications in ageing and AD-related phenotypes

    The genetic architecture of the human cerebral cortex

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    The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

    Uncovering the heterogeneity and temporal complexity of neurodegenerative diseases with Subtype and Stage Inference

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    The heterogeneity of neurodegenerative diseases is a key confound to disease understanding and treatment development, as study cohorts typically include multiple phenotypes on distinct disease trajectories. Here we introduce a machine-learning technique\u2014Subtype and Stage Inference (SuStaIn)\u2014able to uncover data-driven disease phenotypes with distinct temporal progression patterns, from widely available cross-sectional patient studies. Results from imaging studies in two neurodegenerative diseases reveal subgroups and their distinct trajectories of regional neurodegeneration. In genetic frontotemporal dementia, SuStaIn identifies genotypes from imaging alone, validating its ability to identify subtypes; further the technique reveals within-genotype heterogeneity. In Alzheimer\u2019s disease, SuStaIn uncovers three subtypes, uniquely characterising their temporal complexity. SuStaIn provides fine-grained patient stratification, which substantially enhances the ability to predict conversion between diagnostic categories over standard models that ignore subtype (p = 7.18 7 10 124 ) or temporal stage (p = 3.96 7 10 125 ). SuStaIn offers new promise for enabling disease subtype discovery and precision medicine

    Conversion Discriminative Analysis on Mild Cognitive Impairment Using Multiple Cortical Features from MR Images

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    Neuroimaging measurements derived from magnetic resonance imaging provide important information required for detecting changes related to the progression of mild cognitive impairment (MCI). Cortical features and changes play a crucial role in revealing unique anatomical patterns of brain regions, and further differentiate MCI patients from normal states. Four cortical features, namely, gray matter volume, cortical thickness, surface area, and mean curvature, were explored for discriminative analysis among three groups including the stable MCI (sMCI), the converted MCI (cMCI), and the normal control (NC) groups. In this study, 158 subjects (72 NC, 46 sMCI, and 40 cMCI) were selected from the Alzheimer's Disease Neuroimaging Initiative. A sparse-constrained regression model based on the l2-1-norm was introduced to reduce the feature dimensionality and retrieve essential features for the discrimination of the three groups by using a support vector machine (SVM). An optimized strategy of feature addition based on the weight of each feature was adopted for the SVM classifier in order to achieve the best classification performance. The baseline cortical features combined with the longitudinal measurements for 2 years of follow-up data yielded prominent classification results. In particular, the cortical thickness produced a classification with 98.84% accuracy, 97.5% sensitivity, and 100% specificity for the sMCI–cMCI comparison; 92.37% accuracy, 84.78% sensitivity, and 97.22% specificity for the cMCI–NC comparison; and 93.75% accuracy, 92.5% sensitivity, and 94.44% specificity for the sMCI–NC comparison. The best performances obtained by the SVM classifier using the essential features were 5–40% more than those using all of the retained features. The feasibility of the cortical features for the recognition of anatomical patterns was certified; thus, the proposed method has the potential to improve the clinical diagnosis of sub-types of MCI and predict the risk of its conversion to Alzheimer's disease
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