Articolele autorului Dumitru Iacobas
Link la profilul stiintific al lui Dumitru Iacobas

Effect of microgravity on gene expression in mouse brain.

Changes in gravitational force such as that experienced by astronauts during space flight induce a redistribution of fluids from the caudad to the cephalad portion of the body together with an elimination of normal head-to-foot hydrostatic pressure gradients. To assess brain gene profile changes associated with microgravity and fluid shift, a large-scale analysis of mRNA expression levels was performed in the brains of 2-week control and hindlimb-unloaded

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New protocol in spotting microarray technique

The "spotting" microarray technique, consisting in large sets of DNA sequences spotted on poly-L-lysine-coated glass microscope slides, has been developed to comparatively analyze genome-wide patterns of mRNA expression. It is now a valuable tool employed in order to quantitatively monitor gene expression profiles, as well as to analyze the alterations produced in case of genetic diseases, or induced by different treatments, abnormal nutrition and

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The „patholog” of the genes expression profile, a new tool in defining, evaluating, and classifying genetic diseases.

The paper introduces the pre-Hilbert space of standard gene expression (SSGE) based on the normal variability in gene profiles, as revealed by the "spotting" microarray technique. In this space, every point represents a possible gene profile and every continuous curve a possible genetic evolution. The gene "patholog" is defined as the Euclidean distance separating the representative point of the gene profile from the unit, 0-centered hyperball. It

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Membrane bioelectrogenesis and ionic channel activity simulation under drug action

The concept of the ionic channel, as a protein with more discrete ionic conductance levels, is analyzed and a computer program, aiming to simulate its dynamics under the action of a pharmacological agent, is presented. The binding of a pharmacological agent modifies the set of the possible configurations and the channel energy spectrum. Therefore it modifies the transition probabilities and the dwelling times in the excited (generally conductive)

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Basic program in monitoring and analysing of a living system

An easy to use, for a physiologist, BASIC program based on a previous published theory (Iacobaş & Iacobaş 1985, 1987) is presented. The user should introduce the mean values, the allowed fluctuations and the experimentally determined values (at certain time moments) of the parameters which are satisfactorily describing the living system. The computer will then determine the corresponding values of the dimensionless parameters, will compute the

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A mathematical transcription of a current problem in physiology

The pre-Hilbert space of normal and pathological states of a living organism is built and a set of functions of medical interest are defined on it. Thus we put in mathematical terms the pathological of a state, the drug, the treatment, the length and the therapeutical effect of a treatment and the therapeutical efficiency of a drug.

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Integrated transcriptomic response to cardiac chronic hypoxia: translation regulators and response to stress in cell survival

Complementary deoxyribonucleic acid microarray data from 36 mice subjected for 1, 2, or 4 weeks of their early life to normal atmospheric conditions (normoxia) or chronic intermittent (CIH) or constant (CCH) hypoxia were analyzed to extract organizational principles of the developing heart transcriptome and determine the integrated response to oxygen deprivation. Although both CCH and CIH regulated numerous genes involved in a wide diversity of processes,

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Similar transcriptomic alterations in Cx43 knock-down and knock-out astrocytes

Previous findings of widespread transcriptomic alteration in tissues from connexin null mice raise the issue of whether the transcriptomic changes are directly due to connexin down- regulation or to “compensatory” developmental alterations for the missing gene. To start addressing this question, the authors compared with wild-type control the gene expression profiles of connexin43 (Cx43) knockout and Cx43siRNA knockdown wild-type cortical astro-

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Alteration of transcriptomic networks in adoptive-transfer experimental autoimmune encephalomyelitis

Adoptive transfer experimental autoimmune encephalomyelitis (AT-EAE) is an inflammatory demyelination that recapitulates in mouse spinal cord (SC) the human multiple sclerosis disease. We now analyze previously reported cDNA array data from age-matched young female adult control and passively myelin antigen-sensitized EAE mice with regard to organizational principles of the SC transcriptome in autoimmune demyelination. Although AT-EAE had a large

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Fluid shear stress regulates vascular endothelial growth factor gene in osteoblasts

Fluid-induced shear stress is widely recognized as an important biophysical signal in cell–cell mechanotransduction. To identify cellular signaling pathways that are regulated by fluid shear stress, we applied the unbiased approach of transcriptional profiling. Our cDNA array analysis detected that 1,165 of the 6,288 sampled unigenes were significantly affected by pulsatile fluid flow. GenMapp 2.1 analysis revealed pathways of genes regulated by

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