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At least 865 records · Page 48Linked to original sources
PubMed2004

[Present day psychosomatic medicine].

Article presents the development of psychosomatic medicine, respectively that of behavioral or anthropological medicine, stressing they do not belong to medical disciplines but they represent a way of thinking, which aims to introduce knowledge of humanistic sciences into the classical medicine and to change the orientation of contemporary medicine from the disease to the diseased person. Historically, the new approach represents a systemic course, which leads to the general theory of systems and to cybernetics. These are mathematical and logic sciences, which can be applied in every situation where complex manifestations have to be handled. Problems of human health and disease definitely represent such complexity. Systemic theories also develop as well as their implementation into the medicine. Formulation of the bio-psycho-social approach or the movement of family (systemic) therapy verifies the theory.

Humans↗
PubMed1992

Serotonin related functions in panic-anxiety: a critical overview.

The antipanic utility of imipramine and monoamine oxidase inhibitors has led to hypotheses of noradrenergic and/or serotonin (5-HT)-related abnormalities underlying panic disorder (PD) and its agoraphobic complications. Further data support significant antipanic effects for agents with acute 5-HT reuptake blockade effects. It is unlikely that ameliorative effects observed following chronic administration of 5-HT drugs remain 5-HT specific. Despite a range of recently discovered 5-HT receptor subtypes, evidence for a specific receptor abnormality in PD is lacking. Preclinical studies suggest an important role for 5-HT effects in several animal models of anxiety, including separation-induced infant protest responses and respiratory modulation. Induction of anxiety with putative 5-HT agents such as meth-chloro-phenylpiperazine and fenfluramine lend further support to 5-HT involvement in anxiety states. Critical behavioral, physiologic, and neuroendocrine differences between putative 5-HT anxiogens and "classic" panicogens, such as lactate and carbon dioxide are discussed. We propose that 5-HT agents mediate antipanic effects through amelioration of a deranged internal evaluative mechanism along cybernetic lines, rather than simple augmentation or reduction of 5-HT function.

Animals↗
PubMed2004

Biomechanical background for a noninvasive assessment of bone strength and muscle-bone interactions.

New concepts and methods of study in bone biomechanics defy the prevailing idea that bone strength is determined by a systemically-controlled "mineralized mass" which grows until reaching a peak and then is lost at individually-specific rates. In case of bones, "mass" represents actually the substratum of a structure, the stiffness of which does not depend on the mass, but on the intrinsic stiffness and the spatial distribution of the mineralized material. A feed-back system called "bone mechanostat" seems to orient the osteoblastic and osteoclastic processes of bone, modeling and remodeling, according to the sensing by osteocytes of strains caused in the structure by mechanical usage of the skeleton, in specific directions as determined principally by the customary contractions of regional muscles and impact forces. The endocrine-metabolic systems, crucial for the normal skeletal development, modulate the work of osteocytes, blasts and clasts in a systemic way (i.e., not related to a specific direction of the stimuli). Therefore, they tend actually to interact with, rather than contribute to, the biomechanical control of bone structure. Furthermore, no feed-back loop enabling a cybernetic relationship of those systems with bone is known. Instead of passively letting hormones regulate their "mass" in order to optimize their strength, bones would actively self-regulate their architecture following an anisotropic pattern in order to optimize their stiffness (the only known variable to be ever controlled in the skeleton) and strength "despite of" the endocrine systems. Three practical questions derive from those ideas: 1. Osteoporoses are not "intense osteopenias" but "osteopenic fragilities". 2. The diagnosis of osteopenia could be solved densitometrically; but that of bone fragility is a biomechanical problem which requires auxiliary resources for evaluating the stiffness and the spatial distribution of the mineralized material. 3. Osteopenias and osteoporoses should be on time evaluated as related to the mass or strength of the regional muscles, respectively, in order to differentiate between the "primary" (intrinsic lesion of the mechanostat) or "secondary" (systemic) etiologies and the biomechanical origin (disuse) in each case, with important therapeutic implications.

Biomechanical Phenomena↗
PubMed2005

The case of the missing third.

How is it that form arises out of chaos? In attempting to deal with this primary question, time and again a "Missing Third" is posited that lies between extremes. The problem of the "Missing Third" can be traced through nearly the entire history of thought. The form it takes, the problems that arise from it, the solutions suggested for resolving it, are each representative of an age. This paper traces the issue from Plato and Parmenides in the 4th--5th centuries, B.C.; to Neoplatonism in the 3rd--5th centuries; to Locke and Descartes in the 17th century; on to Berkeley and Kant in the 18th century; Fechner and Wundt in the 19th century; to behaviorism and Gestalt psychology, Jung, early in the 20th century, ethology and cybernetics later in the 20th century, then culminates late in the 20th century, with chaos theory.

Animals↗
PubMed2004

[Research advances in dynamic mechanism and its simulation of eco-hydrological process in forest catchment].

Hydrological process is the key link between climatic fluctuations and ecologic dynamics of forests at spatial and temporal scales. To some extent, global climate change and large-scale human's activities will impact the spatial-temporal changes of eco-hydrological process in forest catchments in the future. Therefore, researches on the dynamic mechanism of eco-hydrological processes in forest catchments play a crucial role in understanding and controlling the rational use of ecological resources, resuming regional ecology, and sustainable development in economy. This paper described the interception, evapotranspiration and rainfall-runoff of forest ecological system and their effects on hydrological process. The spatial structure of soil moisture and its evolution with time were also the cause and consequence of forest. The spatial-temporal interaction between hydrologic and ecologic dynamics, the application of distributed hydrological model, and the eco-hydrological dynamics and cybernetics of forest would be the most exciting frontiers of the relative researches in the future.

Climate↗
PubMedDate not supplied

[Basic principles of computational chemistry for medical biologists].

The lecture describes the basic principles of computational chemistry underlying the methods of molecular modelling used in bioinformatics area. The basic positions, methods of molecular and quantum mechanics and combined approaches are considered. This lecture is from theoretical cycle "Bioinformatics and Computer-Aided Drug Design" for fourth year students of Medico-Biological Department of Russian State Medical University (specialty--biochemistry, biophysics and medical cybernetics). It can also be advised for all students and post-graduate students of medico-biological specialties.

Computational Biology↗
PubMedDate not supplied

[Life forms of organisms as patterns of organization and spatial ecological factors].

Tectological and archaetectonical approaches which are conventionally used in morphology are discussed. The similarity of these approaches to some views on the structure and organization of nature systems was shown. These wiews were originated within the framework of the modern system-cybernetic conception. The morphology particularities of natural object of any rank (from organism to biosphere) allow determination of environment influence character. In some cases intensity of the influence can be determined. This, morphological-geometrical approach of nature investigation acquires high prognostic value. The aspects of "pattern organization" concept and its perspectives are discussed. The patterns of organization of organisms could be characterized only in the context of their interactions with environment. Therefore it is necessary to distinguish new group of ecological factors: spatial or chorological one. It was suggested that spatial ecological factors is predominant if all other physical factors have no extreme values.

Ecology↗
PubMedDate not supplied

Autoregulated extra- and intracorporeal pump system for perfusion.

Recent statistics indicate that one serious event occurs once in every 300 perfusions. We have devised a cybernetic approach using photosensors and pressure sensors at critical points of the circuit which should allow feedback regulation of the bypass according to the changes in venous return. In order to avoid overtransfusion, left atrial pressure control is employed. This also enables automatic weaning and facilitates partial bypass. In the clinical setting a test system proved to be accommodated to prevent gross air contamination of the arterial line. Based on vast clinical experience with the conventional method of extrapulmonary circulation, the logical extension of this work will be the development of a compact pump oxygenator utilizing hemofilters, the pump portion of which can be temporarily implanted until the cardiac function has been restored. It is autoregulated and, if the need arises, controlled by the anesthetist, one of whose primary concerns will be physiological perfusion.

Adult↗
PubMedDate not supplied

Determinants of musculoskeletal frailty and the risk of falls in old age.

Neuromuscular parameters that describe locomotion are indispensable variables for the diagnosis and treatment of frailty, fall risk and osteoporosis. A scientifically-based standardized locomotor assessment should be an essential part of medical examinations in research and clinical practice. There has been no previous consensus regarding which test procedures should be included in a locomotor assessment. The goal of this article is to provide a rationale for the selection of appropriate locomotor tests in a comprehensive locomotor assessment for elderly patients. We propose that a locomotor assessment should comprise the parameters that have been proven predictive for both falls and impending disability. The parameters should be measured in the standard units of physics. Therefore, we propose the following tests for a standardized locomotor assessment: (1) Self-selected gait velocity as the single best measure of general locomotor status and a good predictor of age-related adverse events; (2) Chair rise test (timed 5 chair rises) which measures power on vertical movement and the hip surrounding muscles as the most important neuromuscular risk factor for falls and fall-related fractures; (3) Tandem standing and tandem walking to measure postural capacity (balance) to the side; (4) Timed up and go test as a global screening procedure; (5) Clinical gait analysis with special focus on regularity; and (6) At least on a research level, movement must be measured referring to the terms of physics by mechanography. Mechanography (Leonardo force plate system, Novotec Pforzheim, Germany) records the time course of ground reaction forces, velocity of the vertical movements of the center of mass and power during unrestricted physiological movements. In the mechanogram the eccentric and concentric phases of movements can be differentiated and the storage of energy in the elastic elements of the body can be examined. The kinetics of human movement is explained by mechanograms of a two-legged jump. The ground reaction forces resulting from a jump down from a height of 0,46 m are demonstrated as a performance that is representative for human coordination. One goal of this text is to underline the insights that arise if the rules of physics are applied to human movement. A deeper understanding enables us to create more effective treatments for disorders of the muscle-bone unit. Bringing physics and cybernetics into the field of osteoporosis is a great heritage of Harold Frost.

Accidental Falls↗
PubMed2006

[Expression of osteopontin in the pericystic layer of hepatic hydatid cyst].

OBJECTIVE: To investigate the expression and distribution of osteopontin (OPN) in the pericystic layer of Echinococcus granulosus cyst. METHODS: 60 surgically excised cysts were studied with HE and immunohistochemistry staining by using antibodies specific for OPN. Immunofluorescence double labeling technique and Media Cybernetics Image (Pro Plus 5.1 software) were used to appraise the relationship between the OPN and macrophages (CD68). RESULTS: Expression of OPN was found at various degree in hydatid cysts, 75% (45/60) was distributed in the intra-layer at the parasite side, 8.3% (5/60) distributed in the extra-layer near the side of liver parenchyma ("exocyst"-layer vs "adventitia"-layer, P<0.01). Macrophages were identified between the intra-layer and extra-layer, and OPN was observed in most of the macrophages. Meanwhile, OPN was concurrently found with the deposit of calcium in a similar distribution in the hydatid cyst. CONCLUSION: Osteopontin mainly distributes in the intra-pericystic layer of hepatic hydatid cyst.

Adolescent↗
PubMed1991

Pathophysiological mechanisms of fibromyalgia.

Pain related to fibromyalgia may consist of a complex interaction of nociceptive, neuropathic, dysregulatory central nervous system and psychosomatic mechanisms. Nociceptor pain is based on the excitation of nervous sensors specialized to signal potentially harmful stimuli, i.e., the nociceptors. Metabolic deficiencies in muscle and neurogenic inflammation induced by the release of substance P and other neuropeptides from the peripheral nerve endings may result in chemical sensitization of nociceptors and an ensuing hyperalgesia particularly present in tender points. Neuropathic pain is due to pathological mechanisms within nerve cells and fibers in the peripheral and central nervous system. Pathophysiology may be related to compression (such as in the carpal tunnel syndrome or a vertebral disk herniation) or regeneration of nerves, resulting in ectopic impulse discharges and disturbances of axonal transport. The ensuing neuronal hyperexcitability and trophic changes induced by a disturbed axonal transport system may be major factors of pain in fibromyalgia. Dysregulatory pain denotes pain maintained by dysfunction of efferent control loops. Thus, if spinal motoneuron output results in excessive tension of postural muscle, nociceptors in muscles, tendons and joints might become more excited. Persistent abnormal spinal reflex transmission due to, e.g., peripheral trauma or inappropriate postural habits may result in a vicious circle between muscle hypertension and pain. Similarly, a defective sympathetic control may result in disturbed microcirculation and nociceptor excitation (e.g., in sympathetic algodystrophy). Many symptoms of pain in fibromyalgia (trigger points, pain referral, pain associated with muscle spasm or neurogenic joint immobilization) can be attributed to abnormal control mechanisms in a complex cybernetic system.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1991

Malignant lymphoma in the gastrointestinal tract.

The main function of gut-associated lymphoid tissue is to provide an adaptive protective mechanism to help defend the body from exogenous antigen. This complex function requires the coordination of various cellular elements, including B cells, T cells, macrophages, and the epithelial cells of the gut. The control of this remains poorly defined, but involves various cellular subpopulations, humoral factors acting by autocrine and paracrine means, and cell adhesion molecules regulating tissue tropisms. Disruption of these cybernetic mechanisms is likely to be fundamental to the development and behavior of gut lymphomas. Although conventional histopathology is likely to remain the mainstay of diagnosis and patient management, further advances in the understanding, diagnosis, and therapy of gut lymphomas will require a greater knowledge of the cells and molecules that regulate the lymphoid milieu of the gut.

Gastrointestinal Neoplasms↗
PubMedDate not supplied

[Biological hypotheses in obsessive-compulsive disorder].

Biological hypothesis in obsessive-compulsive disorder is recent and firstly initiated through pharmacological data. The supporting evidences are scant but sufficiently provocating; the review of the literature data on these hypothesis suggests more questions than concluding responses; the introduction of new psychobiological models (like ethologic, cybernetic, cognitive and behavioral models...) and the functional "cutting" (or the transnosologic approach) of the disorder may allow more specific applications for the neurobiological research, and more refined predictions on clinical and experimental observations (responses to psychoactive drugs, biological abnormalities...).

Adult↗
PubMed1991

[Value of the family approach].

Studies of relations between schizophrenics and their family have considerably altered our understanding of the disease and its therapeutic approach. However, on the basis of a multidimensional concept of schizophrenia most clinicians consider that the familial approach should be integrated in the overall management of the patient and his family. Theories of communications integrated in the cybernetic model have thrown a new light on interactions between schizophrenics and their family. Behaviours that looked absurd when studied in isolation acquire a new meaning within the family context. The association of redundant functioning modalities detected in the families of schizophrenics are described. By clarifying the communications within the family and by assisting the members of the family, the patient can be given a chance of progressing.

Family↗
PubMed1990

Evaluation of ECG interpretation systems: signal analysis.

Performance analysis of biosignal processing systems which provide diagnostic statements requires particular care. Besides general accuracy requirements, psychological and legal implications for patient and physician have to be considered on both the development and the user sites. Cybernetics and control engineering have provided the basic methodology for performance analysis of systems: in technical systems often mathematically defined functions and signals can be fed into the system to be tested and its response and output provide the necessary performance characteristics after adequate mathematical analysis. For systems which process biosignals, as for example ECG analysis systems, instead of analytically given signals learning and test sets of data derived from patients have to be applied. The performance analysis is done on a statistical basis. In this paper construction and composition of learning and test data sets as well as methods for performance evaluation of the signal processing part of ECG programs are described. Specific reference is made to the European project Common Standards for Quantitative Electrocardiography (CSE) where ten ECG- and nine VCG-programs have been tested. The results of these tests provide reference data and standards for further program development as well as for independent system performance evaluation.

Electrocardiography↗
PubMed1989

[Analysis of function in shoulder-arm pain].

Aiming at a particularized functional analysis 70 patients with shoulder-hand syndrome were diagnosed; aspects of reflexotherapy (manual and neural therapy) were taken into consideration on this occasion inclusive a comment on the psychical condition. This article refers to several peculiarities of the interaction therapeutist-patient. The importance of radiological aspects is discussed and cybernetic model-conceptions of biological systems are also mentioned. A comprehensive diagnostic differentiation inclusive search for the source of disturbances and a psychological judgement are recommended.

Adult↗
PubMedDate not supplied

[Nozometric algorithms in stomatology].

The intensive development of medical informatics and cybernetics led to the creating of an impressive mathematical apparatus, associated with algorithmization of medical activities and processes. In that aspect, special attention is paid to the nozometric algorithms, applied in the most responsible medical field--therapeutic-diagnostic process. The existing nozometric algorithms are reviewed, with consideration given to the specificity of the stomatological diagnostics. An algorithm set has been systematized that is recommended for use in the field of stomatology.

Algorithms↗
PubMed1989

[Systems theory in medicine and biology].

We try to determinate, that systems theory has to be introduced into modern medicine. The biological roots as well as the cybernetic ones are outlined. Among various concepts about systems theory the evaluation by Riedl seems to be the most efficient to explain medical procedures. His basic informations refer to von Bertalanffy, the additional introduction of a 4-cause-principle, Aristoteles, permits the explanation of complex relations. The examples of tumor and inflammation are used to demonstrate the basic idea of the formal cause as well as the final cause. The latter should also become an important fact in the solution of other medical problems.

Humans↗