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PubMed2003

NMR evidence of a supramolecular structure of water.

The hypothesis advanced in this paper is based on the formation of dissipative structures, in the form of supramolecular structures of water, by virtue of its hydrogen bonds, structurally similar to a liquid crystal. The supramolecular structure could be a macromolecule typical of a living organism (plant or animal), which as we know is approximately 80% water, with a complex conformation induced initially by an active principle and which remains, organising itself as a result of an input of energy (dynamisation, electromagnetic wave or other). Water is the most abundant substance on earth and has been very well studied with a number of model structures having been proposed and refined. Notwithstanding this, it remains an anomalous liquid where no single model is able to explain all of its properties. Recently our research group in Siena carried out NMR studies on the water molecule measuring nuclear spin relaxation times T1 and T2. The phenomena observed lead to the conclusion that water and aqueous solutions should be regarded as continuous polymorphous self-organizing systems. At the macro-level the water behaviour is related with biodiversity, the core of biological evolution.

Hydrogen Bonding↗
PubMedDate not supplied

[It is normal for classification approaches to be diverse].

It is asserted that the postmodern concept of science, unlike the classical ideal, presumes necessary existence of various classification approaches (schools) in taxonomy, each corresponding to a particular aspect of consideration of the "taxic reality". They are set up by diversity of initial epistemological and ontological backgrounds which fix in a certain way a) fragments of that reality allowable for investigation, and b) allowable methods of exploration of the fragments being fixed. It makes it possible to define a taxonomic school as a unity of the above backgrounds together with consideration aspect delimited by them. Two extreme positions of these backgrounds could be recognized in recent taxonomic thought. One of them follows the scholastic tradition of elaboration of a formal and, hence, universal classificatory method ("new typology", numerical phenetics, pattern cladistics). Another one asserts dependence of classificatory approach on the judgment of the nature of taxic reality (natural philosophy, evolutionary schools of taxonomy). Some arguments are put forward in favor of significant impact of evolutionary thinking onto the theory of modern taxonomy. This impact is manifested by the correspondence principle which makes classificatory algorithms (and hence resulting classifications) depending onto initial assumptions about causes of taxic diversity. It is asserted that criteria of "quality" of both classifications proper and classificatory methods can be correctly formulated within the framework of a particular consideration aspect only. For any group of organisms, several particular classifications are rightful to exist, each corresponding to a particular consideration aspect. These classifications could not be arranged along the "better-worse" scale, as they reflect different fragments of the taxic reality. Their mutual interpretation depends on degree of compatibility of background assumptions and of the tasks being resolved. Extensionally, classifications are compatible as much as they coincide by context and hierarchical structure of included taxa. Intentionally, typological classifications are compatible if included taxa are comparable by their diagnoses, while phylogenetic classifications are compatible if the included taxa are ascribed monophyletic status. A brief consideration is given to the "new phylogenetics" (= "genophyletics") as to a classificatory approach aimed at elaboration of parsimonious phylogenetic hypotheses based on molecular biology data and employing numerical methods of cladistic analysis. This approach is shown to borrows some phenetic ideas and revives scholastic principle of unified classificatory basis. It is supposed that, in a time, biological classification would get escaping from plethora of positivistic ideas (including those being developed by nowaday cladistics) and would assimilate (revive) more actively holistic worldview.

Biodiversity↗
PubMed2003

[The distribution and origin of P elements in Drosophila melanogaster strains from northeast China].

Eukaryotic transposable elements, especially P transposable elements of Drosophla, are very important to study the evolution of biology. We collected 130 single--female lines of D. melanogaster from 13 places in Northeast China and 3 places nearby which are Beijing(BC), Yantai (YT), Huhehaote(HHT) in 1999 and 2000. We amplified the fragments from ORF2 to ORF3 of P elements using PCR and calculated the defective frequencies and defective parameters of P elements from different places. Basing on the distribution of defective P elements, we suggested the invasion route of P elements of D. melanogaster in Northeast China. The results indicate that the defective frequencies decrease from the frontier to the inland, and in the isolated places the frequencies are lower. It is proposed that P elements of D. melanogaster in Northeast China originate from Korea and Russia to the frontiers of P.R. China, then expand into the inland.

Animals↗
PubMed2003

Risks and complications of prolonged parenteral antibiotic treatment in children with acute osteoarticular infections.

This study aimed at assessing the prevalence of complications encountered during prolonged intravenous antibiotic (AB) therapy when treating acute osteoarticular (OA) infections in children. We reviewed retrospectively 60 paediatric patients treated in our department between 1988 and 1998 for acute osteoarticular infections (27 with acute haematogenous osteomyelitis, 25 with septic arthritis and 8 with septic osteoarthritis). C-reactive protein, erythrocyte sedimentation rate (ESR), and full blood count were monitored during the entire treatment. Body temperature was recorded three times per day until the fever subsided, and then daily during the remaining hospitalisation. Finally, we listed complications related to the antibiotic therapy and those linked to the presence of a venous catheter. Seventeen allergic reactions to drugs were recorded during the intravenous AB therapy. This complications occurred on average after 24.4 +/- 4.4 days of treatment. The clinical manifestations most often encountered were a delayed rise in temperature and cutaneous symptoms. Blood tests showed an isolated increase in the ESR and eosinophilia (> 1000 eosinophils/ml). Four venous catheters had to be removed, in two cases owing to their obstruction and in two cases owing to an infection. Prolonged intravenous AB therapy is not without complications due to its duration and its mode of administration. Drug allergies to AB constitute a major complication of the treatment. They may render the treatment of subsequent infections problematic and expose these patients to major allergic reactions if they accidentally encounter the molecule incriminated. Moreover, the anaesthetics required to insert a central venous catheter and the need to leave it in place for a prolonged duration constitute another source of potential complications. The duration of i.v. AB therapy could therefore be shortened if the clinical and biological evolution is favourable and the pathogen is identified.

Adolescent↗
PubMed1992

Race and ethnicity as biological constructs.

For some time, biologists and anthropologists have overwhelmingly rejected the partitioning of modern humans into biological "races." An examination of recent human evolutionary history suggests that the zoological definition of race, based on significant genetic differences, cannot be legitimately applied to contemporary humans. Extensive past hybridization, plasticity of the human phenotype, the presence of ecotypes, the lack of extensive molecular information, and the lack of longitudinal multigenerational evaluations of diverse groups contribute to ambiguity in taxonomic assignment. Although biological aggregates do exist, they represent variation below the subspecies level, and, as such, are much more tenuous over evolutionary time. The persistent reference to quasibiological constructs such as ethnicity and race in the lay and scientific literatures requires that ethnicity be scrutinized for possible biological dimensions. The Diop model of ethnicity suggests that at least three components contribute to its formation: a historical factor, a linguistic factor, and a psychological factor, each of which can be examined for possible biological dimensions. Presumed biological affinities may allow certain groups to expand and extend their collective history and amplify their kin networks, possibly improving group biological fitness. Individual and group initial language of acquisition may influence brain physiology and organize the template for interpretation and behavior, creating greater consistency of response across otherwise divergent biological aggregates. Psychological continuity in particular behavioral traits, particularly repetitive multigenerational responses, may have an adaptive aspect at the group level. While ethnicity remains primarily a sociocultural category, it has biological precursors, parameters, and consequences for both individuals and groups. The genetic components of these biological dimensions remain to be identified and quantified.

Anthropology↗
PubMed2004

[The gene flow of population genetic structure].

The difference of population genetic structure is one of the important embodiments of genetic diversity. There is a long history of the study of population genetic structure, and the study of gene flow of population genetic structure is aroused more and more importance. It has an important effect on population genetics, evolution biology, conservation biology and ecology. Although the level of gene flow is estimated by traditional population genetics, there is a large restriction in its precision. With the development of biological technology, the methods of the research on gene flow reach the molecular level. Methods of protein electrophoresis and molecular markers (RAPD, RFLP, VNTR, ISSR and mitochondrial DNA) are used to research gene flow among populations. This paper introduces not only some models of population genetic structure: Continent-Island Model, Island Model, Stepping-Stone Model, Isolation-By-Distance Model and Hierarchical Model; but also the study methods, function and role of gene flow is based on models of population genetic structure, research achievements in recent years and the restriction of the methods.

Alleles↗
PubMedDate not supplied

Lysenko's contributions to biology and his tragedies.

Trofim Denisovich Lysenko's life and work have been much analyzed and discussed in the world's literature. It is well known that Lysenko is notorious and has been regarded as a charlatan. Less well known is that he once made greater contributions to Biology and has been misunderstood in some aspects. In this paper, Lysenko s contributions to plant physiology, genetics, agro-biology and evolutionary biology are briefly reviewed. His tragedies and mistakes, such as mixing science and politics, denying the existence of genes, failing to build up suitable scientific collectives for the metabolism-biochemical studies of heredity, as well as his theoretical one-sidedness, are also discussed, thus reconsidering the case of Lysenko from a comprehensive and objective viewpoint.

Agriculture↗
PubMed2005

Using parallel evolutionary development for a biologically-inspired computer vision system for mobile robots.

We describe a new approach to attacking the problem of robust computer vision for mobile robots. The overall strategy is to mimic the biological evolution of animal vision systems. Our basic imaging sensor is based upon the eye of the common house fly, Musca domestica. The computational algorithms are a mix of traditional image processing, subspace techniques, and multilayer neural networks.

Algorithms↗
PubMedDate not supplied

From the ethology of unicellular eukaryotes to the locomotion of the living beings: meaning and evolution of the phenomenon.

A comparative reappraisal of the general problem of evolutionary trends and constraints of the locomotion phenomenon from prokaryotes to protozoa to metazoa was carried on. They elaborated different propulsive systems, different control systems of motion and different analysis systems of the stimuli. A general understanding of the locomotion phenomenon was reached and ciliate behaviour was positioned within the wider context of the evolution of biological displacement.

Animals↗
PubMedDate not supplied

[Genosystematics: from E. Chargaff and A. N. Belozersky up to date].

A review of history of genosystematics (macromolecular systematics) from E. Chargaff and A. N. Belozersky up to date. The role of A.N. Belozersky and his collaborators in the development of this new branch of systematics is analyzed. Genosystematics was the source of valuable information clarifying some aspects of biological evolution. Its methods were successfully employed in microorganisms--(e.g., discovery of archaebacteria) and in eucaryote systematics (origin of plastids, falcification of "molecular clock" hypothesis, substantial changes in higher plants phylogenetics, etc.). However, attempts to employ some fragmentary and unreliable data obtained by genosystematics for modifying the existing phylogenetic schemes and systems of organisms failed. Nowadays genosystematics is like a newborn child suffering from children's diseases well-known to "classical" systematics. It is rather far from final conclusions describing the evolution of genotypes. Some of its recent achievments, e.g., elaboration of the concept of PhyloCode, allow to believe that this science is able to suggest revolutionary changes in Linnean systematics.

Evolution, Molecular↗
PubMed2005

[Why do so many arts and social scientists have huge difficulties accepting (evolutionary)biologically based opinions for gender differences].

The contribution deals with the wide-spread rejection of (evolutionary) biological founded statements concerning sex differences by social sciences and arts, which are not based on objective objections, but are ideologically justified. The starting point therefore is to be seen in the justified critique of the biological legitimized racism and sexism in the sixties and seventies of the last century. The continuation of this rejecting position, though the modern biology has changed itself essentially, can be explained psychologically by Festinger's "Theory of Cognitive Dissonance".

Art↗
PubMed2005

Low molecular weight heparins in cardiovascular medicine.

Cardiovascular diseases are the major cause of morbidity and mortality in the Western countries and their prevalence is increasing in developing world. The final biological evolution of atherosclerotic process, supporting development and progression of cardiovascular diseases, is thrombosis. In the most recent years several clinical trails have established that low molecular weight heparins play a major role in the area of prevention and treatment of arterial and venous thrombosis. It is now established, that low molecular weight heparins are efficacious and safe anticoagulant options for patients with deep vein thrombosis, pulmonary embolism, unstable angina and non-ST-segment elevation myocardial infarction. In addition, low molecular weight heparins play a major role to prevent thromboembolic events in patients with chronic diseases (e.g. due to cerebrovascular ischemic events, cancer) and in patients undergoing surgical interventions. Clinical trials have also shown that low molecular weight heparins might play a role in the treatment of patients with ST-segment elevation acute myocardial infarction, in the prevention of thrombotic events in patients with congestive heart failure, and in patients undergoing percutaneous coronary interventions. The combined use of low molecular weight heparins with fibrinolysis and other antithrombotic agents has been also studies in a number of clinical trials. This review summarises the results of the most recent clinical studies regarding the use of low molecular weight heparins in prevention and treatment of cardiovascular diseases.

Anticoagulants↗