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The impact of anaesthesia upon the main functions of the animal organism  [PDF]
N?stas? V.,,Mariana Grecu
Medicamentul Veterinar , 2007,
Abstract: The general anesthetics produce the reversible loss of consciousness and sensitivity and influence the vital functions of the organism. More than a century ago, the anesthetic was considered to be a poison which intoxicates the nervous system. Recently, it has been proved that the anesthetic substance invades all tissues. Despite these drawbacks, they are widely used in the experimental researches “in vivo”, but their use may considerably change the result of the physiological or pharmacological effects of these substances; thepharmacological details are few. The aim of this communication is to provide information referring to the interactions between general anesthetics and other pharmacological agents, limiting at the substances currently used in the experimental research.
Genomic Variability within an Organism Exposes Its Cell Lineage Tree  [PDF]
Dan Frumkin ,Adam Wasserstrom ,Shai Kaplan,Uriel Feige,Ehud Shapiro
PLOS Computational Biology , 2005, DOI: 10.1371/journal.pcbi.0010050
Abstract: What is the lineage relation among the cells of an organism? The answer is sought by developmental biology, immunology, stem cell research, brain research, and cancer research, yet complete cell lineage trees have been reconstructed only for simple organisms such as Caenorhabditis elegans. We discovered that somatic mutations accumulated during normal development of a higher organism implicitly encode its entire cell lineage tree with very high precision. Our mathematical analysis of known mutation rates in microsatellites (MSs) shows that the entire cell lineage tree of a human embryo, or a mouse, in which no cell is a descendent of more than 40 divisions, can be reconstructed from information on somatic MS mutations alone with no errors, with probability greater than 99.95%. Analyzing all ~1.5 million MSs of each cell of an organism may not be practical at present, but we also show that in a genetically unstable organism, analyzing only a few hundred MSs may suffice to reconstruct portions of its cell lineage tree. We demonstrate the utility of the approach by reconstructing cell lineage trees from DNA samples of a human cell line displaying MS instability. Our discovery and its associated procedure, which we have automated, may point the way to a future “Human Cell Lineage Project” that would aim to resolve fundamental open questions in biology and medicine by reconstructing ever larger portions of the human cell lineage tree.
Genomic Variability within an Organism Exposes Its Cell Lineage Tree.
Frumkin Dan,Wasserstrom Adam,Kaplan Shai,Feige Uriel
PLOS Computational Biology , 2005,
Abstract: What is the lineage relation among the cells of an organism? The answer is sought by developmental biology, immunology, stem cell research, brain research, and cancer research, yet complete cell lineage trees have been reconstructed only for simple organisms such as Caenorhabditis elegans. We discovered that somatic mutations accumulated during normal development of a higher organism implicitly encode its entire cell lineage tree with very high precision. Our mathematical analysis of known mutation rates in microsatellites (MSs) shows that the entire cell lineage tree of a human embryo, or a mouse, in which no cell is a descendent of more than 40 divisions, can be reconstructed from information on somatic MS mutations alone with no errors, with probability greater than 99.95%. Analyzing all ~1.5 million MSs of each cell of an organism may not be practical at present, but we also show that in a genetically unstable organism, analyzing only a few hundred MSs may suffice to reconstruct portions of its cell lineage tree. We demonstrate the utility of the approach by reconstructing cell lineage trees from DNA samples of a human cell line displaying MS instability. Our discovery and its associated procedure, which we have automated, may point the way to a future "Human Cell Lineage Project" that would aim to resolve fundamental open questions in biology and medicine by reconstructing ever larger portions of the human cell lineage tree.
Initiation and spread of escape waves within animal groups  [PDF]
James Herbert-Read,Jerome Buhl,Feng Hu,Ashley Ward,David Sumpter
Quantitative Biology , 2014, DOI: 10.1098/rsos.140355
Abstract: The exceptional reactivity of animal collectives to predatory attacks is thought to be due to rapid, but local, transfer of information between group members. These groups turn together in unison and produce escape waves. However, it is not clear how escape waves are created from local interactions, nor is it understood how these patterns are shaped by natural selection. By startling schools of fish with a simulated attack in an experimental arena, we demonstrate that changes in the direction and speed by a small percentage of individuals that detect the danger initiate an escape wave. This escape wave consists of a densely packed band of individuals that causes other school members to change direction. In the majority of cases this wave passes through the entire group. We use a simulation model to demonstrate that this mechanism can, through local interactions alone, produce arbitrarily large escape waves. In the model, when we set the group density to that seen in real fish schools, we find that the risk to the members at the edge of the group is roughly equal to the risk of those within the group. Our experiments and modelling results provide a plausible explanation for how escape waves propagate in Nature without centralised control.
Interstellar dust within the life cycle of the interstellar medium  [cached]
Demyk K.
EPJ Web of Conferences , 2012, DOI: 10.1051/epjconf/20111803001
Abstract: Cosmic dust is omnipresent in the Universe. Its presence influences the evolution of the astronomical objects which in turn modify its physical and chemical properties. The nature of cosmic dust, its intimate coupling with its environment, constitute a rich field of research based on observations, modelling and experimental work. This review presents the observations of the different components of interstellar dust and discusses their evolution during the life cycle of the interstellar medium.
Contrasting Attitudes towards Animal Welfare Issues within the Food Chain  [PDF]
Fabio Napolitano,Maria Serrapica,Ada Braghieri
Animals , 2013, DOI: 10.3390/ani3020551
Abstract: Intensive systems have facilitated the production of animal-based products at relatively low prices. On one hand, these methods have been increasingly considered to be responsible for a dramatic reduction in animal welfare, as indicated by the high prevalence of stereotypies in sows, brittle bones in hens, lameness in broilers and short life span in dairy cattle. As a consequence, large segments of animal welfare-sensitive consumers have been identified. On the other hand, price conscious consumers, if accepting higher prices, are more likely to require explicit justification of returns in quality. Therefore, scientifically validated monitoring systems for assessing the welfare of farm animals have been developed in order to provide a certification system, allow the differentiation of animal-based products through constant and reliable signaling systems, and promote animal welfare friendly farming systems.
Emergence, development and diversification of the TGF-β signalling pathway within the animal kingdom
Lukasz Huminiecki, Leon Goldovsky, Shiri Freilich, Aristidis Moustakas, Christos Ouzounis, Carl-Henrik Heldin
BMC Evolutionary Biology , 2009, DOI: 10.1186/1471-2148-9-28
Abstract: After an investigation of 33 genomes, we show that the emergence of the TGF-β pathway coincided with appearance of the first known animal species. The primordial pathway repertoire consisted of four Smads and four receptors, similar to those observed in the extant genome of the early diverging tablet animal (Trichoplax adhaerens). We subsequently retrace duplications in ancestral genomes on the lineage leading to humans, as well as lineage-specific duplications, such as those which gave rise to novel Smads and receptors in teleost fishes. We conclude that the diversification of the TGF-β pathway can be parsimoniously explained according to the 2R model, with additional rounds of duplications in teleost fishes. Finally, we investigate duplications followed by accelerated evolution which gave rise to an atypical TGF-β pathway in free-living bacterial feeding nematodes of the genus Rhabditis.Our results challenge the view of well-conserved developmental pathways. The TGF-β signal transduction engine has expanded through gene duplication, continually adopting new functions, as animals grew in anatomical complexity, colonized new environments, and developed an active immune system.Most genes belong to gene families, which have emerged through consecutive cycles of gene duplications during evolution [1]. With the availability of entire genome sequences, much progress has been made towards the understanding of gene duplication dynamics [2,3] and the evolutionary forces responsible for the retention of a proportion of duplicate genes, such as neo-functionalization [4] and sub-functionalization [5], both at the level of gene expression patterns [6,7] and protein sequence evolution [8]. However, further investigation is required to understand how genomic processes, such as gene duplications and losses, result in higher-level co-ordinated molecular events, such as the emergence of novel signal transduction pathways, which in turn give rise to phenotypic innovations, such as no
Nocturnal thoracoabdominal asynchrony in house dust mite-sensitive nonhuman primates
XiaoJia Wang, Shaun Reece, Stephen Olmstead, et al
Journal of Asthma and Allergy , 2010, DOI: http://dx.doi.org/10.2147/JAA.S11781
Abstract: cturnal thoracoabdominal asynchrony in house dust mite-sensitive nonhuman primates Methodology (2240) Total Article Views Authors: XiaoJia Wang, Shaun Reece, Stephen Olmstead, et al Published Date July 2010 Volume 2010:3 Pages 75 - 86 DOI: http://dx.doi.org/10.2147/JAA.S11781 XiaoJia Wang, Shaun Reece, Stephen Olmstead, Robert L Wardle, Michael R Van Scott Department of Physiology, East Carolina University, Greenville, North Carolina, USA Abstract: Nocturnal bronchoconstriction is a common symptom of asthma in humans, but is poorly documented in animal models. Thoracoabdominal asynchrony (TAA) is a noninvasive clinical indication of airway obstruction. In this study, respiratory inductive plethysmography (RIP) was used to document nocturnal TAA in house dust mite (HDM)-sensitive Cynomolgus macaques. Dynamic compliance (Cdyn) and lung resistance (RL) measured in anesthetized -animals at rest and following exposure to HDM allergen, methacholine, and albuterol were highly -correlated with three RIP parameters associated with TAA, ie, phase angle of the rib cage and abdomen waveforms (PhAng), baseline effort phase relation (eBPRL) and effort phase relation (ePhRL). Twenty-one allergic subjects were challenged with HDM early in the morning, and eBPRL and ePhRL were monitored for 20 hours after provocation. Fifteen of the allergic subjects exhibited gradual increases in eBPRL and ePhRL between midnight and 6 am, with peak activity at 4 am. However, as in humans, this nocturnal response was highly variable both between subjects and within subjects over time. The results document that TAA in this nonhuman primate model of asthma is highly correlated with Cdyn and RL, and demonstrate that animals exhibiting acute responses to allergen exposure during the day also exhibit nocturnal TAA.
The Spatial Association of Gene Expression Evolves from Synchrony to Asynchrony and Stochasticity with Age  [PDF]
Qi Wang, Jianhua Huang, Xinmin Zhang, Bin Wu, Xiaoyu Liu, Ziyin Shen
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024076
Abstract: For multicellular organisms, different tissues coordinate to integrate physiological functions, although this systematically and gradually declines in the aging process. Therefore, an association exists between tissue coordination and aging, and investigating the evolution of tissue coordination with age is of interest. In the past decade, both common and heterogeneous aging processes among tissues were extensively investigated. The results on spatial association of gene changes that determine lifespan appear complex and paradoxical. To reconcile observed commonality and heterogeneity of gene changes among tissues and to address evolution feature of tissue coordination with age, we introduced a new analytical strategy to systematically analyze genome-wide spatio-temporal gene expression profiles. We first applied the approach to natural aging process in three species (Rat, Mouse and Drosophila) and then to anti-aging process in Mouse. The results demonstrated that temporal gene expression alteration in different tissues experiences a progressive association evolution from spatial synchrony to asynchrony and stochasticity with age. This implies that tissue coordination gradually declines with age. Male mice showed earlier spatial asynchrony in gene expression than females, suggesting that male animals are more prone to aging than females. The confirmed anti-aging interventions (resveratrol and caloric restriction) enhanced tissue coordination, indicating their underlying anti-aging mechanism on multiple tissue levels. Further, functional analysis suggested asynchronous DNA/protein damage accumulation as well as asynchronous repair, modification and degradation of DNA/protein in tissues possibly contributes to asynchronous and stochastic changes of tissue microenvironment. This increased risk for a variety of age-related diseases such as neurodegeneration and cancer that eventually accelerate organismal aging and death. Our study suggests a novel molecular event occurring in aging process of multicellular species that may represent an intrinsic molecular mechanism of aging.
Bacterial superantigens and organism physiological status: a theoretical approach  [cached]
Lucian Hritcu,Alin Ciobica,Marius Stefan
Analele ?tiin?ifice Ale Universit??ii Alexandru Ioan Cuza din Ia?i,Sectiunea II A : Genetica si Biologie Moleculara , 2009,
Abstract: : The present review was undertaken in order to present the bacterial superantigens influences on the organism physiological status. In recent years, a great deal of a new knowledge about a group of microbial proteins known as superantigens has been generated. These molecules have elicited tremendous interest because they interact with the immune system in a nonconventional manner and can potentially trigger diseases such as toxic shock, food poisoning, and autoimmunity. Moreover, evidence from clinical observations, animal models of disease, and studies with cell lines indicate an intimate association between bacteria (and bacterial products) and the pathophysiology of many nervous disorders. In summary, knowing the immunological and biological effects of superantigens will help to discern the mechanism of pathogenesis of a number of diseases linked to microbial infections and will offer new possibilities for the development of novel and effective therapeutic strategies.
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