The logic of noncompliance: Management of epilepsy from the patient's point of view

Culture, Medicine, and Psychiatry - Studies of patient compliance with medical regimens reveal that one-quarter to one-half of patients act at variance with their physician's suggestions. Using...     

Disease from the point of view of evolution

In the process of evolution, such compensatory reactions as enhanced absorption of sodium chloride and an increase of arterial pressure could be formed only for compensation of acute pathological states (blood loss, dehydration). At present they remain similarly adequate in acute disturbances of blood circulation and of water-electrolyte balance. However, in severe chronic pathology of heart and kidney they often lose their compensatory function and even become dangerous. Evolution of man and of human society has created novel social conditions of adaptation. They are of humanitarian and technogenic character by promoting prevention and treatment of diseases.     

The pediatrician's point of view

Summary Children are exposed to indoor and outdoor air pollution. Whereas normal children can suffer such air condition without long term sequellae, other children at risk can develop, since infancy, bronchopulmonary disease either because of bad conditions of life or congenital or hereditary causes.     

Uncoupling proteins: the issues from a biochemist point of view

The functional characteristics of uncoupling proteins (UCP) are reviewed, with the main focus on the results with isolated and reconstituted proteins. UCP1 from brown adipose tissue, the paradigm of the UCP subfamily, is treated in more detail. The issues addressed are the role and mechanism of fatty acids, the nucleotide binding, the regulation by pH and the identification by mutagenesis of residues involved in these functions. The transport and regulatory functions of UCP2 and 3 are reviewed in comparison to UCP1. The inconsistencies of a proposed nucleotide insensitive H(+) transport by these UCPs as concluded from the expression in yeast and Escherichia coli are elucidated. In both expression system UCP 2 and 3 are not in or cannot be converted to a functionally native state and thus also for these UCPs a nucleotide regulated H (+) transport is postulated.     

Statistical fluctuations in processes of gene expression regulation: consideration of the problem from point of view of statistical mechanics

The regulation of gene expression is a basic problem of biology. In some cases, the gene activity is regulated by specific binding of regulatory proteins to DNA. In terms of statistical mechanics, this binding is described as the process of adsorption of ligands on the one-dimensional lattice and has a probability nature. As a random physical process, the adsorption of regulatory proteins on DNA introduces a noise to the regulation of gene activity. We derived equations, which make it possible to estimate this noise in the case of the binding of the lac repressor to the operator and showed that these estimates correspond to experimental data. Many ligands are able to bind nonspecifically to DNA. Nonspecific binding is characterized by a lesser equilibrium constant but a greater number of binding sites on the DNA, as compared with specific binding. Relations are presented, which enable one to estimate the probability of the binding of a ligand on a specific site and on nonspecific sites on DNA. The competition between specific and nonspecific binding of regulatory proteins plays a great role in the regulation of gene activity. Similar to the one-dimensional "lattice gas" of particles, ligands adsorbed on DNA produce "one-dimensional" pressure on proteins located at the termini of free regions of DNA. This pressure, an analog of osmotic pressure, may be of importance in processes leading to changes in chromatin structure and activation of gene expression.     

Genetic code from tRNA point of view

The possible codon-anticodon pairings follow the standard genetic code, yet in a different mode. The corresponding rules for decoding sequence of the codons in mRNA with tRNA may be called "tRNA code". In this paper we analyse the mutational and translational stability of such tRNA code. Our approach is based on the model of "ambiguous intermediate" and on the study of underlying block structure and Eulerean graph technique. It is shown that the wobble rules and the reduced number of tRNA anticodons strongly affect the mutational and translational stability of the code. The selection of tRNA anticodons, besides the optimization of translation, also ensures the more reliable start and, to a lesser extent, the stop of translation. The attribution of tRNA anticodons to the groups [WWW, WWS, SWW, SWS] and [SSS, SSW, WSS, WSW] as well as [MMM, MMK, KMM, KMK] and [KKK, KKM, MKK, MKM] clearly correlates with class I and class II aminoacyl-tRNA synthetases and obeys the principle of the optimal coding in both cases. Both W-S and M-K groupings also refer to the encoding of amino acids with the large and small side-chain volumes, which may provide such an attribution. The higher variability of tRNA code agrees with the suggestions that the variations in an assignment of tRNA anticodons may serve as the driving force generating the different variants of the genetic code.     

Terpenoids from seeds of Abies firma

Nine monoterpenoids, 16 sesquiterpenoids including two novel compounds, 12 diterpenoids and sitosterol were identified in seeds of Abies firma. Two new selinane-type compounds were isolated and their structures were determined as 4α-methoxy-selina-11-ene and 11-hydroxy-4α-methoxy-selinane on the basis of chemical and spectroscopic evidence.     

The dark side of cohesin: the carcinogenic point of view

Genome instability is a hallmark of cancer cells and how it arises is still not completely understood. Correct chromosome segregation is a pre-requisite for preserving genome integrity. Cohesin helps to ensure faithful chromosome segregation during cell cycle, however, much evidence regarding its functions have come to light over the last few years and suggest that cohesin plays multiple roles in the maintenance of genome stability. Here we review our rapidly increasing knowledge on the involvement of cohesin pathway in genome stability and cancer.     

The human embryo: a scientist's point of view

...Thus, my judgement is that a human embryo is not a human person, and so we may do experiments on it which involve killing it. But my judgement is also that a human embryo has the potential to become a human being. The consequence of this attribute is that it imposes limits on the kinds of experiments which may be performed on human embryos. It is this which sets the boundaries. Experiments which may harm the embryo while still allowing it subsequently to realise its potential, and become a person, should not be permitted. It is the potentiality of the human embryo which governs our behaviour towards it. Its potential makes it special, and radically different from any other human tissue. This potential which the early embryo has means that great respect must always be accorded it, and great thought and care must surround any dealings with it....     

The LAP family: a phylogenetic point of view

Recently, the LAP (for 'LRR and PDZ') family of adaptor proteins was described in vertebrates and invertebrates. The proteins are involved in cell polarity and receptor targeting, and they contain both LRR and PDZ domains in the same molecule, a combination that is specifically bilaterian. A search of available genome sequences reveals a limited number of lap genes, which we have classified by phylogenetic analysis. We propose a functional hypothesis for the origin of this protein family in bilaterians, and give a phylogenetic interpretation of their diversity.