Connections between obesity and dyslipidaemia.

The importance of the obesity-lipid connection has suffered from the traditional reductionism view of science. Excess body weight has rarely been deemed an independent risk factor for coronary heart disease, directing physicians to target therapies towards the risk factors that excess body weight modifies (e.g. raising HDL, lowering blood pressure) instead of targeting the cause. The efforts of Adult Treatment Panel III to define and identify the metabolic syndrome as a secondary target may spur practitioners to revisit the need for weight management in patients with lipid disorders.     

Filamentous Connections between Ediacaran Fronds

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Connections between growth and the cell cycle

To maintain a constant size during cellular proliferation, a cell's growth rate must match its rate of division. Factors that govern proliferation must therefore coordinately regulate two distinct processes: the cellular biosynthesis that drives accumulation of mass, and progression through the cell division cycle. Recent work has identified several mechanisms which couple cell division to growth. Different mechanisms are used at different times during development to coordinate growth, cell division, and patterning.     

Connections between species diversity and genetic diversity

Species diversity and genetic diversity remain the nearly exclusive domains of community ecology and population genetics, respectively, despite repeated recognition in the literature over the past 30 years of close parallels between these two levels of diversity. Species diversity within communities and genetic diversity within populations are hypothesized to co‐vary in space or time because of locality characteristics that influence the two levels of diversity via parallel processes, or because of direct effects of one level of diversity on the other via several different mechanisms. Here, we draw on a wide range of studies in ecology and evolution to examine the theoretical underpinnings of these hypotheses, review relevant empirical literature, and outline an agenda for future research. The plausibility of species diversity–genetic diversity relationships is supported by a variety of theoretical and empirical studies, and several recent studies provide direct, though preliminary support. Focusing on potential connections between species diversity and genetic diversity complements other approaches to synthesis at the ecology–evolution interface, and should contribute to conceptual unification of biodiversity research at the levels of genes and species.     

Connections between epigenetic gene silencing and human disease

Alterations in epigenetic gene regulation are associated with human disease. Here, we discuss connections between DNA methylation and histone methylation, providing examples in which defects in these processes are linked with disease. Mutations in genes encoding DNA methyltransferases and proteins that bind methylated cytosine residues cause changes in gene expression and alterations in the patterns of DNA methylation. These changes are associated with cancer and congenital diseases due to defects in imprinting. Gene expression is also controlled through histone methylation. Altered levels of methyltransferases that modify lysine 27 of histone H3 (K27H3) and lysine 9 of histone H3 (K9H3) correlate with changes in Rb signaling and disruption of the cell cycle in cancer cells. The K27H3 mark recruits a Polycomb complex involved in regulating stem cell pluripotency, silencing of developmentally regulated genes, and controlling cancer progression. The K9H3 methyl mark recruits HP1, a structural protein that plays a role in heterochromatin formation, gene silencing, and viral latency. Cells exhibiting altered levels of HP1 are predicted to show a loss of silencing at genes regulating cancer progression. Gene silencing through K27H3 and K9H3 can involve histone deacetylation and DNA methylation, suggesting cross talk between epigenetic silencing systems through direct interactions among the various players. The reversible nature of these epigenetic modifications offers therapeutic possibilities for a wide spectrum of disease.     

Finding Novel Molecular Connections between Developmental Processes and Disease

Identifying molecular connections between developmental processes and disease can lead to new hypotheses about health risks at all stages of life. Here we introduce a new approach to identifying significant connections between gene sets and disease genes, and apply it to several gene sets related to human development. To overcome the limits of incomplete and imperfect information linking genes to disease, we pool genes within disease subtrees in the MeSH taxonomy, and we demonstrate that such pooling improves the power and accuracy of our approach. Significance is assessed through permutation. We created a web-based visualization tool to facilitate multi-scale exploration of this large collection of significant connections (http://gda.cs.tufts.edu/development). High-level analysis of the results reveals expected connections between tissue-specific developmental processes and diseases linked to those tissues, and widespread connections to developmental disorders and cancers. Yet interesting new hypotheses may be derived from examining the unexpected connections. We highlight and discuss the implications of three such connections, linking dementia with bone development, polycystic ovary syndrome with cardiovascular development, and retinopathy of prematurity with lung development. Our results provide additional evidence that plays a key role in the early pathogenesis of polycystic ovary syndrome. Our evidence also suggests that the VEGF pathway and downstream NFKB signaling may explain the complex relationship between bronchopulmonary dysplasia and retinopathy of prematurity, and may form a bridge between two currently-competing hypotheses about the molecular origins of bronchopulmonary dysplasia. Further data exploration and similar queries about other gene sets may generate a variety of new information about the molecular relationships between additional diseases.     

Connections between the phrenic arteries and various visceral arteries]

During an angiographic research carried out over more than 1100 cases, some connections between the phrenic arteries and the arteries of the hepatic, superior mesenteric and renal districts were observed. The AA. point out the presence of these connections even of thin calibre, their right prevalence (71%), and their uncertain embryologic origin.     

Classification of epileptic seizures using wavelet packet log energy and norm entropies with recurrent Elman neural network classifier

Electroencephalogram shortly termed as EEG is considered as the fundamental segment for the assessment of the neural activities in the brain. In cognitive neuroscience domain, EEG-based assessment method is found to be superior due to its non-invasive ability to detect deep brain structure while exhibiting superior spatial resolutions. Especially for studying the neurodynamic behavior of epileptic seizures, EEG recordings reflect the neuronal activity of the brain and thus provide required clinical diagnostic information for the neurologist. This specific proposed study makes use of wavelet packet based log and norm entropies with a recurrent Elman neural network (REN) for the automated detection of epileptic seizures. Three conditions, normal, pre-ictal and epileptic EEG recordings were considered for the proposed study. An adaptive Weiner filter was initially applied to remove the power line noise of 50 Hz from raw EEG recordings. Raw EEGs were segmented into 1 s patterns to ensure stationarity of the signal. Then wavelet packet using Haar wavelet with a five level decomposition was introduced and two entropies, log and norm were estimated and were applied to REN classifier to perform binary classification. The non-linear Wilcoxon statistical test was applied to observe the variation in the features under these conditions. The effect of log energy entropy (without wavelets) was also studied. It was found from the simulation results that the wavelet packet log entropy with REN classifier yielded a classification accuracy of 99.70 % for normal-pre-ictal, 99.70 % for normal-epileptic and 99.85 % for pre-ictal-epileptic.     

Biological adaptabilities and quantum entropies.

The entropy-based theory of adaptability set forth by Michael Conrad in the early 1970s continued to appear in his work for over two decades, and was the subject of the only book he published in his lifetime. He applied this theory to a host of subjects ranging from enzyme dynamics to sociology. This paper reviews the formalism of adaptability theory, clarifying some of its mathematical and interpretive difficulties. The theory frames the computational tradeoff principle, a thesis that was the most frequently recurring claim in his work. The formulation of adaptability theory presented here allows the introduction of quantum entropy functions into the theory, revealing an interesting relationship between adaptability and another one of Conrad's deep preoccupations, the role of quantum processes in life.