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PubMed2002

The basic principles of building an ergonomic component of automated training systems.

In recent years, in view of the transformation in education in the Russian Federation, it has been necessary to introduce different technical facilities and new educational methods into the educational process. An introduction of training systems into the educational process concerns every educational method. New methods use various results from such fields as pedagogy, psychology, cybernetics, mathematics, and linguistics. Automated training systems consist of 3 components: informational, didactic, and ergonomic. This paper considers 2 components: didactic and ergonomic. They provide maximum learning with minimum energy consumption on the part of the trainee, in acceptable working conditions. As an example, this paper considers educational systems of calculus mathematics and mathematical geophysics realized in the Novosibirsk State University and Institute, Russian Federation.

Automation↗
PubMed1990

Putative mechanism of blood pressure reduction induced by increases in dietary calcium intake.

An increase in dietary calcium intake lowers blood pressure in spontaneously hypertensive rats and in some patients with arterial hypertension. The mechanisms by which this decrease come about are not clear. A membrane-stabilizing effect wrought by an increase in extracellular calcium would appear unlikely, since the increases in extracellular calcium concentration with increased dietary intake are minimal. Calcium regulatory hormones may be the mediators, and a cybernetic framework has been suggested. Striking defects have been reported in the calcium handling and hormonal household of the spontaneously hypertensive rat. However, a clear cut relationship in terms of a hormonal "template" has not yet been identified in prospective experiments. Data have been presented to show that increased calcium intake has a direct effect on regulatory areas in the brain. However, the mechanisms by which such a response would be mediated are entirely unknown. Increased calcium intake may induce natriuresis. It has been suggested that increased calcium intake helps the "salt sensitive"; however, prospective studies to this effect have not been presented. Increased calcium intake may induce phosphaturia. However, the evidence that blood pressure lowering effects are mediated by phosphate depletion are unconvincing. Some evidence suggests that increased calcium intake may influence local regulatory processes which in turn influences cell integrity and growth. At this point, a unifying hypothesis is not available. However, the clues to various possibilities are intriguing.

Animals↗
PubMed2005

The Systemic Theory of Living Systems and Relevance to CAM: The Theory (Part II).

This theory stems from observing the universe's 'omniscient' nature, manifested in flows of energy and information of its life plethora. A notorious example is the living cell's intelligent nature, which guides its basic goal: to maximize survival. This last motivated me to address the living system's intelligence, which constitutes a vital and controversial topic, its relationship with 'incurable' disease in general, including cancer, and to propose golden rules for therapeutics, as well as a definition of ideal medicine. The scientific confirmation of these findings is embedded in discoveries in cybernetics, biological theory of information and modern thermodynamic concepts, concerning energy and information exchange, within a living system. This approach's practical application, denominated Systemic Medicine, has been substantiated by treatment and results obtained in >300 000 patients suffering from chronic degenerative diseases.

Journal Article↗
PubMed1987

Role of the central nervous system in the adult respiratory distress syndrome.

The CNS might play an important pathophysiologic role in the induction of the adult respiratory distress syndrome (ARDS). Post-traumatic development of cerebral microthromboses seems to be a major feature. To test this hypothesis, we subjected Wistar rats with postburn ARDS to the following microneurosurgical procedures in an attempt to morphologically detect modifications in the evolving pattern: a) anterior (AH) or posterior (PH) hypothalamus nuclei stereotaxic electrolytic lesion; b) intracerebroventricular microinjections of phenoxybenzamine (PB)-50, micrograms propranolol-0.5 micrograms, cocaine-5 micrograms, epinephrine-0.5 micrograms, carbachol(CA)-5 micrograms, pirilamine-20 micrograms, cimetidine-30 micrograms, lidocaine-20 micrograms, atropine (AT)-40 micrograms; c) intra-AH microinjections of CA-10 micrograms, AT-20 micrograms; and d) intra-PH microinjections of PB-10 micrograms, norepinephrine-0.05 microgram. The results showed that the alpha-adrenergic components of PH induce a potentiation in ARDS whereas the cholinergic components of AH seem to attenuate this syndrome. This work suggests that a damaged CNS may suffer cybernetic derangements as to induce it to generate inappropriate adaptative responses that can result in the development of ARDS.

Animals↗
PubMed1995

Oxygen status of arterial and mixed venous blood.

OBJECTIVES: To describe system requirements for determination of the oxygen status of the blood using the oxygen status algorithm, a computer program. To define the oxygen extractivity, a term we propose, of the arterial blood and the oxygen extraction tension. To describe the different causes of tissue hypoxia, and the clinical interpretation of mixed venous oxygen tension and oxygen consumption rate. DATA SOURCES: Previous physiological and clinical studies related to oxygen status of the blood. DATA SYNTHESIS: The oxygen status algorithm calculates the oxygen extraction tension and generates the oxygen graph as an aid in interpreting oxygen status of the patient. A cybernetic scheme explains the causes of tissue hypoxia and forms the basis for the interpretation of changes in the mixed venous oxygen tension. A diagram with the mixed venous oxygen tension on the abscissa and the oxygen consumption rate on the ordinate illustrates the oxygen flux dependent oxygen consumption rate. A graph shows the relationship between mixed venous oxygen tension and oxygen delivery. CONCLUSIONS: The oxygen status of arterial blood comprises three groups of quantities related to arterial oxygen tension, hemoglobin oxygen capacity, and hemoglobin oxygen affinity. Disturbances in one of these groups may be compensated by opposite changes in one or both of the other. The oxygen extraction tension indicates the degree of compensation, and mixed venous oxygen tension is the key parameter in evaluating the presence of a state of oxygen flux-dependent oxidative metabolism.

Algorithms↗
PubMed1986

Acute respiratory distress syndrome (ARDS): the prophylactic effect of neurodepressant agents.

It has been suggested that acute respiratory distress syndrome (ARDS) is induced by a cybernetic imbalance of the central nervous system secondary to alarm reaction-provoked intravascular coagulation into cerebral microvessels. The brain metabolic and electrical resting state through the use of neurodepressant drugs might theoretically reduce the intensity and duration of the alarm reaction, thus diminishing the possibility of self-induced secondary brain lesions. In this work, Wistar rats were submitted to central (anterior hypothalamic electrolytic lesion) and peripheral (scald burn) trauma as effective models of reproducing an ARDS-like syndrome. Pretreatment of these animals with the following neurodepressant drugs: morphine, pentobarbital sodium, haloperidol, diazepam, chlorpromazine, and urethane, resulted in significant attenuation of the evolution of the ARDS-like syndrome, reinforcing the suggestion of a centrally-based origin of such pathologic manifestations.

Animals↗
PubMed2000

Quantitative analysis of tympanic membrane disease using video-otoscopy.

OBJECTIVE: To perform quantitative analysis of pathological changes in the tympanic membrane using video-otoscopic images. STUDY DESIGN: Prospective case-control study. METHODS: Forty-two ears of children with chronic otitis media with effusion (OME) and 15 ears of normal children were included in this study. Tympanic membrane images were captured and digitized using a Welch-Allyn (Skaneatales Falls, NY) VDX-300 Illumination and Imaging system with S-VHS input to a MIRO DC 30 (Pinnacle Systems, Mountain View, CA) visual board in a Power PC-based computer. These images were visualized and recorded during static and pneumatic pressure changes. Quantitative analysis of tympanic membrane disease was performed using Image Pro Plus Imaging software (Media Cybernetics, Del Mar, CA). The measurements included area of the tympanic membrane and its quadrants, area of tympanic membrane involved by disease, angle formed at the umbo, and length of the malleus versus vertical length of the tympanic membrane. RESULTS: Tympanosclerosis was present in 57% of ears and occurred most frequently in the anteroinferior quadrant, but the maximum area of involvement was in the posteroinferior quadrant. The ratio of the angles formed at the umbo was significantly greater (P = .01) for the OME group compared with the control group. The ratio of the length of the umbo and the vertical length of the tympanic membrane was almost identical for the OME and the control groups (P = .4). CONCLUSIONS: Videootoscopic images can be used for quantitative analysis of tympanic membrane disease. The ratio of the posterior angle to the anterior angle formed at the umbo seems to be a more reliable indicator of post otitis media than is a reduced length of the long process of malleus.

Adolescent↗
PubMed2001

Determination of ototoxicity of common otic drops using isolated cochlear outer hair cells.

OBJECTIVES: Otic drops are commonly used not only for otitis externa, but also for otorrhea in the presence of tympanostomy tubes or tympanic membrane perforations. Many studies have demonstrated the ototoxicity of common otic preparations such as Cortisporin otic drops (Monarch Pharmaceuticals, Bristol, TN). The purpose of this study was to assess the relative ototoxicity of common otic preparations by direct exposure to isolated cochlear outer hair cells (OHCs). METHODS: OHCs from adult chinchilla cochlea were exposed to standard bathing solution (control), acetic acid, Acetasol HC (Alpharma USPD Inc., Baltimore, MD), Gentacidin (CIBA Vision Ophthalmics, Atlanta, GA), and Tobradex (Alcon, Fort Worth, TX). The cells were observed using an inverted microscope, and the images were recorded in digital still-frame and video, and analyzed on the Image Pro-Plus 3.0 program (Media Cybernetics, Silver Spring, MD). RESULTS AND CONCLUSIONS: As measured by time to cell death and change in morphology of OHCs, acetic acid with or without hydrocortisone was most toxic to OHCs. Cortisporin was more cytotoxic than gentamicin and Tobradex.

Acetic Acid↗
PubMedDate not supplied

Constructing a team model: creating a foundation for evidence-based teams.

Teams are the fundamental element of work in the contemporary clinical setting. As interdisciplinary teams become an essential component of the evidence-based framework for clinical practice, their formalization, integration, and synthesis within the practice framework will become increasingly mandatory. Outlined here is a contextual model for team action that is formalized as the organizational leadership continuously addresses the structural and process components of team dynamics in a continuous and cybernetic frame that assures all of the elements of effective teamwork. The theoretical foundations for team modeling are explicated, the elements of the systems approach to team process are outlined, and a necessary synthesis of team processes is described and established as a foundation for evidence-based clinical practice.

Attitude of Health Personnel↗
PubMed1997

Scoliosis and developmental theory: adolescent idiopathic scoliosis.

STUDY DESIGN: Statistical analysis of maturity and asymmetry criteria in adolescent idiopathic scoliosis. OBJECTIVES: To explore the hypothesis that scoliosis is a manifestation of developmental destabilization under physiologic stress. BACKGROUND: Advances in genetics and theoretical biology have broadened the understanding of morphogenesis and the controlling mechanisms for the development of the adult form. The morphologic genome can be viewed as a cybernetic control system, and the homeobox genes can be viewed as the master controls for the specific subroutines. Deformity will occur from a faulty "program" or a disturbance in the running of that program. An early and subtle indication of such an occurrence is failure of bilateral symmetry. METHODS: An analysis of variance in Cobb angle, age at diagnosis, and apical site in 327 girls with spinal curves 5 degrees or greater according to prospectively maintained scoliosis screening records was performed. Dermatoglyphics were compared in 114 female control individuals and 164 female patients with adolescent idiopathic scoliosis (minimum Cobb angle, 10 degrees), and then by subdivision into school screening (n = 86) and general clinic referrals (n = 78). RESULTS: Girls from the screening program (from the years 1979-1990) had statistically significant associations between age and apical vertebra, suggesting an age-deformity relationship independent of maturation and growth spurt. Girls with adolescent idiopathic scoliosis from a later cohort, both screened and unscreened, had increased directional asymmetry, as previously reported. There was a statistically significant increase in fluctuating asymmetry in general clinic referrals when compared with school screening referrals. CONCLUSIONS: Developmental instability can explain adolescent idiopathic scoliosis as part of wider developmental theory without the necessity of a disease process in the etiology. The differences between screening and general clinic referrals suggest the need for natural history studies, and treatment protocols also should consider the provenance of the individuals described.

Adolescent↗
PubMed2005

Buccal bone plate thickness of the Asian people.

Distances from the apex to the buccal bone plate were measured on the computed tomography (CT) images of 1806 teeth from 66 patients, using an image analyzer program (Image-Pro Plus, Ver. 4.0, Media Cybernetics). In the mandible, the mean distance from the distal apex of the mandibular second molar to the buccal bone plate was the largest distance measured, at 8.51 mm, followed by distance from the mesial root to the buccal bone (7.34 mm). In the mandibular first molar, the mean distal and mesial bone thicknesses were 5.18 mm and 4.09 mm, respectively. However, when there were two distal roots, the distance of the disto-lingual root to the buccal plate was found to be 9.52 mm, which constitutes the greatest measured thickness. In the maxillary buccal roots, the distances from the mesio-buccal and disto-buccal root of the second molar to the buccal bone plate were the largest, at 4.63 mm and 3.61 mm, respectively. The average distances from the palatal apex of the maxillary first and second molars to the buccal bone plate were 10.69 mm and 10.17 mm, respectively, while, from the palatal bone plate, average distances of 3.15 mm and 3.08 mm were measured. Special considerations, such as bony lid approach, lingual approach, or intentional replantation may be required, especially when a patient has a surgical need in the second molars and the disto-lingual root of the mandibular first molar, or in the palatal root of the maxillary molars.

Adolescent↗
PubMed2001

Practical issues and concepts in vagus nerve stimulation: a nursing review.

Estimates of epilepsy incidence among the U.S. population range between 0.5% and 1%. The most common type of seizure in adult patients is partial onset. Approximately 20% of these patients are refractory to antiepileptic drug therapy and experience intolerable side effects such as confusion, dizziness, weight gain, lethargy, and ataxia. The ketogenic diet appears to be beneficial for children but is not considered a standard option for adults. Epilepsy surgery can be an option for many and may offer control or a reduction in seizures. However, many patients are opposed to cranial surgery or may not tolerate the ketogenic diet. Recent advances in biomedical technology and perfection in surgical techniques have shown vagus nerve stimulation (VNS) using the Neuro Cybernetic Prosthesis (NCP) system is an effective new treatment option in reducing seizure frequency. On July 16, 1997, the U.S. Food and Drug Administration (FDA) approved the use of the NCP for vagus nerve stimulation, as an adjunctive treatment for refractory partial onset seizures in adults and adolescents over 12 years of age. Murphy et al. and Wheless have reported similar results in children younger than 12 years. VNS represents the first therapy using a medical device approved by the FDA for the treatment of refractory seizures. An estimated 10,000 patients have been implanted with the device.

Adolescent↗
PubMed2003

Intelligence with representation.

Behaviour-based robotics has always been inspired by earlier cybernetics work such as that of W. Grey Walter. It emphasizes that intelligence can be achieved without the kinds of representations common in symbolic AI systems. The paper argues that such representations might indeed not be needed for many aspects of sensory-motor intelligence but become a crucial issue when bootstrapping to higher levels of cognition. It proposes a scenario in the form of evolutionary language games by which embodied agents develop situated grounded representations adapted to their needs and the conventions emerging in the population.

Adaptation, Physiological↗
PubMed1991

Structural heterogeneity of membrane receptors and GTP-binding proteins and its functional consequences for signal transduction.

Recent information obtained, mainly by recombinant cDNA technology, on structural heterogeneity of hormone and transmitter receptors, of GTP-binding proteins (G-proteins) and, especially, of G-protein-linked receptors is reviewed and the implications of structural heterogeneity for diversity of hormone and transmitter actions is discussed. For the future, three-dimensional structural analysis of membrane proteins participating in signal transmission and transduction pathways is needed in order to understand the molecular basis of allosteric regulatory mechanisms governing the interactions between these proteins including hysteretic properties and cell-cybernetic aspects.

Acetylcholine↗
PubMed1996

Minimally invasive neurosurgery.

BACKGROUND: The philosophy and practice of minimally invasive surgery have fundamentally altered the practice of general and gynaecological surgery, and are currently transforming the practice of neurosurgery. The goal of minimally invasive surgery is to reduce tissue disruption and thus morbidity. This is a review of the development, applications, and benefits of minimally invasive neurosurgery, and its wider surgical implications. METHODS: A synthesis of the literature is presented. RESULTS: Interactive computer imaging with frame-based and frameless stereotaxy, ultrasonographic and endoscopic techniques are increasingly being used independently and in combination in order to execute minimally invasive approaches and to navigate a safe path within the cranium or spine. Interaction using an interlinking stereotactic instrument or robot between the surgeon, a graphic interface (such as a computer workstation) and the patient, enables precise planning and execution of surgery with exact correspondence of imaging data and the living pathology. The direct influence of virtual reality, cybernetics, robotics, and telepresence will further revolutionize the practice of neurosurgery and will impact increasingly on other surgical disciplines. Safety and precision are further enhanced by intra-operative physiological monitoring techniques. Interventional neuroradiology and stereotactic radiosurgery add further dimensions to the minimally invasive approach and may not only diminish the need for open surgery, but in selected cases obviate the need altogether. CONCLUSIONS: Minimally invasive neurosurgery is a major force in contemporary neurosurgery and many of the current neurosurgical applications will have far-reaching effects on the practice of surgery in general.

Brain↗
PubMed1984

The clinical significance of endometrial prolactin.

Prolactin (PRL) is produced not only by the anterior pituitary gland but also by human endometrium. That decidual stromal cells secrete PRL from day 22 of the menstrual cycle is demonstrated by: 1) nett accumulation of PRL during in vitro culture; 2) PRL accumulation is prevented by inhibitors of protein synthesis; and 3) identification of PRL mRNA within endometrial decidua. Endometrial PRL is biologically and immunologically equipotent with pituitary PRL and its amino acid sequence is very similar. In human pregnancy, decidual PRL binds to receptors on the fetal chorion and amnion and thereby passes into amniotic fluid in high concentration. Three putative functions of uterine PRL are suggested from current studies: a) a PRL receptor defect is present in the chorion laeve of patients with pregnancies complicated by chronic polyhydramnios and this deficiency in chorionic receptors for endometrial PRL may result in the development of excessive amniotic fluid; b) decidual PRL may modulate prostaglandin synthesis not only within the endometrium prior to menstruation, but also within the chorion and amnion to allow labour to proceed in a timely manner; and c) amniotic fluid PRL may pass into the fetal tracheo-bronchial system to promote surfactant production. Unlike pituitary PRL with distant target organs, decidual PRL appears to have paracrine or cybernetic functions in the human uterus, placental membranes and the fetus.

Decidua↗
PubMed1998

Vagus nerve stimulation.

Left vagus nerve stimulation (VNS) is a promising new treatment for epilepsy. In 1997, VNS was approved in the United States as an adjunctive treatment for medically refractory partial-onset seizures in adults and adolescents. For some patients with partial-onset seizures, the adverse effects of antiepileptic drugs (AEDs) are intolerable; for others, no single AED or combination of anticonvulsant agents is effective. Cerebral resective surgery is an option to pharmacotherapy in some cases, but many patients with partial-onset seizures are not optimal candidates for intracranial surgery. VNS entails implantation of a programmable signal generator--the Neuro-cybernetic Prosthesis (NCP)--in the chest cavity. The stimulating electrodes of the NCP carry electrical signals from the generator to the left vagus nerve. Although the mechanism of action of VNS is not known, controlled studies have shown that it is safe and well-tolerated by patients with long-standing partial-onset epilepsy. Side effects, which are generally of mild to moderate severity, almost always disappear after the stimulation settings are adjusted. Encouraging results have also been reported in pediatric patients.

Adolescent↗