Disturbance Of Equilibrium Research Articles

Timing versus duration

Rapidly accumulating evidence indicates that clinically used general anesthesia causes massive, widespread neuroapoptotic degeneration in the developing mammalian brain. Susceptibility to anesthesia-induced neurotoxicity has been documented in rats, mice, guinea pigs, primates, and in this study, piglets; in short, anesthesia-induced developmental neuroapoptosis is not species-dependent. Our findings with piglets, like those in other immature mammals, demonstrate that relatively short exposure to anesthesia is just as detrimental to species with long periods of synaptogenesis as it is to those with short periods of synaptogenesis. However, the highly reproducible findings in different species also indicate that the timing of exposure to anesthesia is critically important; that is, brain regions that are at the peak of synaptogenesis are most vulnerable even when the exposure to anesthesia is relatively brief. Because the peak of synaptogenesis is characterized by intense, highly programmed neuronal communication that is vital for the survival and proper function of immature neurons, we conclude that anesthesia causes severe disturbances in the fine equilibrium between excitatory and inhibitory neurotransmission in the developing mammalian brain, ultimately leading to neuronal redundancy and death.

Anticipatory postural muscle activity associated with bilateral arm flexion while standing in individuals with spastic diplegic cerebral palsy: A pilot study

Compared to automatic postural responses to external perturbation, little is known about anticipatory postural adjustments in individuals with spastic diplegic cerebral palsy. In this study, we examined whether anticipatory activation of postural muscles would be observed before voluntary arm movement while standing in individuals with spastic diplegia. Seven individuals with spastic diplegia (SDCP group, 12–22 years) and 7 age- and gender-matched individuals without disability (Control group) participated in this study. Participants performed bilateral arm flexion at maximum speed at their own timing while standing, during which electromyographic (EMG) activities of focal and postural muscles were recorded. In both groups, the erector spinae (ES) and medial hamstring (MH) muscles were activated in advance of the anterior deltoid muscle (AD), which is a focal muscle of arm flexion. Although start times of ES and MH with respect to AD were similar in the 2 groups, increases in EMG amplitudes of ES and MH in the anticipatory range from −150 ms to +50 ms, with respect to burst onset of AD, were significantly smaller in the SDCP group than in the Control group. These findings suggest that individuals with spastic diplegia have the ability to anticipate the effects of disturbance of posture and equilibrium caused by arm movement and to activate postural muscles in advance of focal muscles. However, it is likely that the anticipatory increase in postural muscle activity is insufficient in individuals with spastic diplegia.

The Evolution of the Theoretical Foundations of Punctuated Equilibrium Theory in Public Policy

Punctuated equilibrium theory in public policy replicated from biological punctuated equilibrium theory has concluded that public policies alternate between stasis and punctuation. However, recent research on Pacific Northwest forest policy, U.S. state tobacco policy, and U.S federal auto efficiency policy have found no punctuations despite an attempt to do so. What is the efficacy of using biological punctuated equilibrium theory to also explain punctuated equilibrium in public policy? Significant differences exist between biological and public policy punctuated equilibrium theory including time frames for change, what constitutes outside disturbances of equilibrium, venues of punctuated equilibrium, levels of analysis for change, and patterns of change. Most policy research on punctuation has focused on the “tone” of media coverage related to change. Some recent studies concluding no punctuation occurred have focused on government action or inaction. Proving strong inference in scientific research requires a clear and viable syllogism linked to appropriate methodology. Both of these crucial elements are now in question in punctuated equilibrium research in public policy.

Therapeutic targeting of chemokine interactions in atherosclerosis

Atherosclerosis is a chronic inflammatory disease of the arterial wall that is characterized by a disturbed equilibrium of immune responses and lipid accumulation, leading to the development of plaques. The atherogenic influx of mononuclear cells is orchestrated by chemokines and their receptors. Studies using gene-deficient mice and antagonists based on peptides and small molecules have generated insight into targeting chemokine-receptor axes for treating atherosclerosis, which might complement lipid-lowering strategies and risk factor modulation. Combined inhibition of multiple chemokine axes could interfere with the contributions of chemokines to disease progression at specific cells, stages or sites. In addition, the recently characterized heterophilic interactions of chemokines might present a novel target for the treatment and prevention of inflammatory diseases such as atherosclerosis.

On the Character of Isostatic Equilibrium Disturbances

Summary The data of disturbances of the isostasy of the Earth’s crust and their relation to different tectonic zones give valuable information about processes in the Earth’s crust. They may be used for the evaluation of some physical parameters, for example of the asthenosphere viscosity. The last value is usually determined on the basis of the data on postglacial uplift, but there are doubts that these values can be applied to the regions with different tectonics. For this reason we have studied as a first step the character of disturbances of the isostasy in the areas of different tectonics. It was ascertained that disturbances of the isostatic equilibrium are the result of the active geotectonic process and that isostatic forces are passive as tectonic factor. In the geological time scale the readjustment takes place instantaneously, therefore isostatic anomalies of gravity may be considered as direct indications of the modern tectonic activity. Regular relations between isostatic disturbances and the character of the latest tectonic movements can be clearly revealed by the comparison of the isostatic anomalies maps with the schemes of Cenozoic crustal movements in the different tectonic zones. In particular, the antii ostatic movements of the Earth’s crust are very common features. The relations revealed between the isostatic gi avity anomalies and tectonic movements permit us to make some conclusions about the character of internal processes in the Earth. The data of isostasy are used for the evaluation of some physical parameters, characterizing the Earth’s crust state and its upper mantle. For example, for the evaluation of the asthenosphere viscosity the data are used which gives the study of Quaternary glaciations. The variety of tectonic conditions on the Earth’s surface reflects different processes taking place in the Earth’s interior and evidently shows different physical conditions. Because of this we are not sure that the results obtained from the study of isostasy in regions of glaciations (representing, as a rule, preCambrian shields) may be extrapolated on the regions differing by their tectonic positions. The results of the study of Quaternary glaciations give quite low values of the viscosity of the asthenosphere and very small times of readjustment (103-105 years). At the same time on the Earth’s surface numerous and great disturbances of equilibrium are known, manifesting in large isostatic anomalies of gravity. This fact is of great interest for an investigator. Firstly, it is very important to clear up the nature of the connection between the disturbances of isostasy and the movements of the Earth‘s crust and the change of the character of these correlations in areas of different tectonic conditions. A number of investigations has been carried out by well-known scientists: Vening Meinesz, van Bemmelen, Bullard, Lyustikh and others. On the basis of the data of isostatic gravity anomalies collected in the Institute of Physics of the Earth in Moscow an attempt was made to find basic features of isostasy in regions of different tectonics, and also the number of more particular correlations within the boundaries tectonic zones. (Artemyev 1962, 1963, 1964.)

平衡障害を唯一の主訴とした小児キアリ奇形Ｉ型の２例

Chiari malformation type I, a congenital condition, the distorts and displaces cerebellar tonsils, inferior cerebellum, and medulla and involoves invagination from the foramen magnum into the upper cervical canal. We report 2 such pediatric cases. Detailed medical histories were obtained for both the-7-year old girl and the boy, who was 3 years and 7 months old, together with routine equilibrium function examinations, neurootological tests, electronystagmography (ENG), and stabilometry. No choked discs were observed on fundoscopy in either case. Vertical downbeat nystagmus through the Frentzel spectales and saccadic pursuits in circular eye tracking tests (CETT) with ENG both suggested cerebellum and brainstem disturbance in the optokinetic pattern test (OKP), and obvious abnormal ities were seen in upright standing control in stabilometry, confirened in magnetic resonance imaging (MRI) centering on the posterior cranial fossa, especially the cerebellumand brainstem. Both were diagnosed with Chiari malformation type I in T1-enhanced imaging. In diagnosing subjects with dizziness and equilibrium disturbance, we can emphasize the importance of detailed inquiry backed by considerable experience among function the physician involved important information souces in both of these cases.

Cereulide and Valinomycin, Two Important Natural Dodecadepsipeptides with Ionophoretic Activities

Cereulide produced by Bacillus cereus sensu stricto and valinomycin synthesized mainly by Streptomyces spp. are natural dodecadepsipeptide ionophores that act as potassium transporters. Moreover, they comprise three repetitions of similar tetrapeptide motifs synthesized by nonribosomal peptide synthesis complexes. Resemblances in their structure find their reflections in the same way of action. The toxicity of valinomycin and cereulide is an effect of the disturbance of ionic equilibrium and transmembrane potential that may influence the whole organism and then cause fatal consequences. The vlm and ces operons encoding valinomycin and cereulide are both composed of two large, similar synthetase genes, one thioestrase gene and four other ORFs with unknown activities. In spite of the characterization of valinomycin and cereulide, genetic determinants encoding their biosynthesis have not yet been clarified.

In-situ sampling of soil pore water: evaluation of linear-type microdialysis probes and suction cups at varied moisture contents

Environmental context. There is a need for slightly invasive techniques capable of in-situ probing of target analytes in environmental compartments. Owing to its passive sampling mode and small probe dimensions, microdialysis-based dosimetry is an appealing tool for monitoring of solute concentrations in both water bodies and pore soil waters with minimum disturbance of natural equilibrium. The development of field applications is challenging but will provide novel insights as to the speciation and bioaccessibility of environmental pollutants, e.g. trace metals, at high spatial resolution. Abstract. In-situ sampling of soil pore water is still a challenge for environmental scientists. Here, microdialysis is explored for probing metal concentrations in soil pore water at soil moisture contents ranging from 50 to 115% of the maximal water holding capacity and is compared with traditional sampling by suction cups. Metal concentrations obtained by the suction cup technique were consistently larger than those measured in the dialysate. Good agreement was obtained for Pb and Cu at soil moistures close to saturation after accounting for diffusion resistances whereas corrected Ni and Cd concentrations in the dialysates exceeded those measured by the suction cup technique. These deviations reflect inherent differences in the sampling mode and effects of soil heterogeneity at the microscale. Microdialysis offers new opportunities to probe solute concentrations at high spatial resolution and minimal disturbance of soil conditions at environmental interfaces such as the plant rhizosphere or at the transition between forest floors and the mineral soil.

Higijena, higijenske navike i zdravlje stanovništva

Hygiene habits are very important for public health. The man is constantly exposed to unfavorable health habits, which leads to fatigue and exhaust of adoptive mechanisms, that weeks defensive capabilities of organism, leads to disturbance of equilibrium between man and his environment and so disease begins. The aim of the study is to comprehend hygiene habits of Serbian population related to territory, type of settlement, sex, age, education and wealthy state. Data of inquiry held by Institute for public health of Serbia in 2000. and 2006. are analyzed. Results of the analysis showed that personal hygiene habits are not satisfactory. Only 75,7% of school children wash their hands regularly, 61,9% shower themselves several times a week, 56,7% brush their teeth several times a day. This is worse in adult population - about 74% wash their hands regularly, 57% shower themselves regularly, and only about 41% brush their teeth. This is significantly better in urban population than in rural, women than men, more educated and richer population. Before meal 88% wash hands, after toilet 90,7%, and after entering the house only 69,6%. Habit of teeth brushing is the least presented - several times a day only 15% inhabitants, and 7,6% don't brush their teeth at all. Habits of teeth brushing are very different related to age - 20,6% of primary school children never brushes their teeth or only periodically, the same does about 12% of high school children, in population from 20 - 34 years only 11,3%, and after 65 years 43,7%. The habit of bathing isn't any better. Only 49,6% bath every day, and 4 - 6 times a week 12,9%. All these habits are significantly better in women than men.

Chemokines in the vascular inflammatory response of atherosclerosis

Atherosclerosis is considered to be a chronic inflammatory disease of the vessel wall that encompasses the accumulation of lipids, and it is critically shaped by the recruitment of leucocytes during all phases of the disease. In addition, the progression of atherosclerosis is determined by a disturbed equilibrium of immune responses. Chemokines and their receptors are instrumental in orchestrating the influx of leucocytes to the vascular wall, but also seem to regulate immune functions. Recent work has shed light on the apparent redundancy and the robustness of the chemokine system and has also provided evidence for its specialized role in the regulation of specific functions and trafficking of leucocyte subpopulations. This review will give a comprehensive summary to highlight those chemokines addressed in different models of atherosclerosis and vascular injury to date. In addition, we will discuss recent developments scrutinizing heterophilic interactions of chemokines that have advanced our understanding of how chemokines control vascular inflammatory responses.

RNA surveillance: molecular approaches in transcript quality control and their implications in clinical diseases.

Production of mature mRNAs that encode functional proteins involves highly complex pathways of synthesis, processing and surveillance. At numerous steps during the maturation process, the mRNA transcript undergoes scrutiny by cellular quality control machinery. This extensive RNA surveillance ensures that only correctly processed mature mRNAs are translated and precludes production of aberrant transcripts that could encode mutant or possibly deleterious proteins. Recent advances in elucidating the molecular mechanisms of mRNA processing have demonstrated the existence of an integrated network of events, and have revealed that a variety of human diseases are caused by disturbances in the well-coordinated molecular equilibrium of these events. From a medical perspective, both loss and gain of function are relevant, and a considerable number of different diseases exemplify the importance of the mechanistic function of RNA surveillance in a cell. Here, mechanistic hallmarks of mRNA processing steps are reviewed, highlighting the medical relevance of their deregulation and how the understanding of such mechanisms can contribute to the development of therapeutic strategies.

Onset of natural convection in the electrochemical cell with horizontal electrodes under non-steady-state conditions: A numerical study

The disturbance of mechanical equilibrium of stagnant electrolyte containing three types of ions and the onset of natural convection in the electrochemical cell with plane horizontal electrodes under the non-steady-state conditions are studied theoretically. The Navier-Stokes equations in the Boussinesq approximation, the equations of ionic transfer of electrolyte components, which is caused by diffusion, convection, and migration, and the electroneutrality condition were used as the mathematical model of the process. Using the numerical simulation, the regularities of the onset of natural convection of electrolyte solution with the formation of convective cells are studied. The effect of transport properties of solution on the critical time of onset of convection and on the time before the current starts to increase due to the onset of natural convection, on the sizes and shape of convective cells and the mass-transfer rate is investigated by the example of cathodic deposition of metal at the limiting current.

Functional brain magnetic resonance imaging in healthy people receiving acupuncture at Waiguan versus Waiguan plus Yanglingquan points: a randomized controlled trial

To observe the cerebral activating effects of needling at Waiguan (SJ5) versus SJ5 plus Yanglingquan (GB34) points in young healthy volunteers based on the hypothesis of "needling effect of combined acupuncture points relates to the brain activation". Sixteen healthy volunteers were randomly divided into SJ5 group and SJ5 plus GB34 group, and there were 8 volunteers in each group. The volunteers in the two groups received needling at corresponding points on the right hand or foot respectively. Nuclear magnetic resonance (1.5T, GE Corporation) was used for functional magnetic resonance imaging (fMRI) of the brain before and during the needling, and the obtained experimental data in the regional brain were processed and analyzed by the method of region of interest (ROI). The ROI activation induced by needling of SJ5 or SJ5 plus GB34 was all relatively concentrated (activation rate more than 4 or activation point more than 10) on bilateral frontal and parietal lobes. There were no significant differences in ROI activation rates of brain regions between the two groups. ROI activation points showed that needling at SJ5 could activate the right cerebellum specifically (P < 0.05, vs SJ5 plus GB34), while needling at SJ5 plus GB34 could activate the left parietal and occipital lobes and bilateral basal ganglion more effectively than activate the other brain regions (P < 0.05, vs SJ5). ROI activation strength showed that needling at SJ5 plus GB34 could more strongly activate the right cerebellum (P < 0.05, vs SJ5). Based on fMRI data, a kind of acupuncture point combination of SJ5 and GB34 within the hand-foot Shaoyang meridians, could improve the motor and sensory dysfunctions and equilibrium disturbance. The effect of combined acupuncture points was proved by cerebral activity initially.

Oxidative stress parameters after combined fluoxetine and acetylsalicylic acid therapy in depressive patients

There are numerous reports indicating disturbed equilibrium between oxidative processes and antioxidative defense in patients with depression. Moreover, depressive patients are characterized by the presence of elements of an inflammatory process, which is one of the sources of reactive oxygen species (ROS). In view of the above, it was decided to study both the effect of fluoxetine monotherapy and that of fluoxetine co-administered with acetylsalicylic acid on lipid peroxidation and antioxidative defense in patients with the first depressive episode in their life. Seventy seven patients with major depressive disorder (MDD), divided into two groups were included in the study. The first group, consisting of 52 patients, received fluoxetine 20 mg, and the second one, in addition to fluoxetine 20 mg, received 150 mg of acetylsalicylic acid. The activity of antioxidative enzymes, copper-zinc superoxide dismutase (CuZnSOD, SOD1), catalase (CAT), glutathione peroxidase (GPSH-x) and the concentration of malonyldialdehyde (MDA) was determined in erythrocytes, whereas the total antioxidant status (TAS) was determined in the plasma. All parameters were measured before and after three month therapy. The obtained results indicate a significant decrease in the activity of SOD1, CAT and GSHP-x, as well as in MDA concentration after the combined therapy. Also a significant TAS increase was observed after the combined therapy. The study demonstrated that combined therapy with fluoxetine and ASA is characterized by the same efficacy and clinical safety as fluoxetine monotherapy, resulting additionally in improvement of oxidative stress parameters in the patients treated for depression.

Fluxes of Heavy Metals from a Highly Polluted Watershed During Flood Events: A Case Study of the Litavka River, Czech Republic

The Litavka River (length 56 km, watershed area 630 km2, average flow at the outlet to the Berounka River 2.57 m3 s−1) drains the historical mining, ore processing, and smelting region of Přibram. This Ag–Pb–Zn±Sb ore district (production from the thirteenth century to 1978, locally to 1980) is known for extensive heavy metal contamination. Recent contamination of the Litavka River system is mostly related to the erosion of contaminated soils and fluvial floodplains sediments, especially from a low-gradient river section located immediately below the ore district, where the fine-grained floodplain sediments are from 1.0 to 1.7 m thick. Radiocarbon accelerator mass spectrometry dating of charcoal fragments separated from one floodplain profile showed calibrated 14C age in the range AD 1220–1284 at a depth of 1.2 m below the surface, while depths of 0.4 and 0.8 m yielded ages in the range AD 1680–1939. Formation of this floodplain was related to disturbance of the river equilibrium resulting from deforestation and the influx of fine-grained material from ore processing, including historical failures of settling ponds. Fluxes of heavy metals during flood events in the Litavka River were studied 35 km downstream below the ore district. Metals are transported here mostly (more than 99% for Pb) in the form of suspended particulate matter (SPM), which at the outlet of the Litavka River contains 2,016 mg kg−1 Zn, 918 mg kg−1 Pb, and 25.5 mg kg−1 Cd on average. During a snowmelt-related minor flood event between March 25 and 29, 2006 (peak flow 36.6 m3 s−1), the river transported 2,400 tonnes of SPM during 4 days, containing 74 kg of Cd, 2,954 kg of Pb, and 5,811 kg of Zn. During larger floods (water flows above 55 m3 s−1 have occurred here 27 times during the last 77 years), the contamination is more diluted by material eroded in the floodplain along the middle and lower river course.

ZENO HEATING AND ANTI-ZENO COOLING BY FREQUENT QUANTUM MEASUREMENTS

We study disturbances of thermal equilibrium between two-level systems (TLS) and a bath by frequent and brief quantum measurements of the TLS energy-states. If the measurements induce either the Zeno or the anti-Zeno regime, namely, the slowdown or speedup of the TLS relaxation, then the resulting entropy and temperature of both the system and the bath are found to be completely determined by the measurement rate, and unrelated to what is expected by standard thermodynamical rules that hold for markovian baths. These anomalies allow for very fast control heating, cooling and state-purification (entropy reduction) of quantum systems much sooner than their thermal equilibration time.

Risk Presented by Copernicia prunifera Palm Trees in the Rhodnius nasutus Distribution in a Chagas Disease-endemic Area of the Brazilian Northeast

With the aid of live-bait traps, we studied the risk that Copernicia prunifera palm trees, present in both periurban and rural localities of an endemic Brazilian northeast Chagas disease region, represent to domestic infestation by Rhodnius nasutus. In this area, this important vector has been encountered harboring and transmitting Trypanosoma cruzi, the etiologic agent of the American trypanosomiasis, to mammals, possibly including humans. Results indicate that this bug colonizes C. prunifera palm trees of both regions, mainly in dry seasons, and is infected with high levels of T. cruzi. Although more triatomines were captured in rural areas, proportionally the number of infected bugs from peri-urban regions was much higher. Herein we address the epidemiologic implications and challenge for the Brazilian health authorities to control the disease in this region, where the native palm trees have been largely destroyed causing a severe disturbance in the environmental equilibrium.

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Cerebellar ataxia in sheep grazing pastures infested with Romulea rosea (onion grass or Guildford grass)

There have been anecdotal reports since 1962 of 'staggers' in sheep grazing Romulea rosea infested pastures, but this is the first detailed account. In September 2005, a locomotor disorder developed in 12 of 120 Merino wethers that had grazed R. rosea infested pasture at Albury, New South Wales, over several months. Affected sheep displayed signs that included limb paresis, knuckling over in the fetlocks, fine head tremor, incoordination, and an equilibrium disturbance characterised by frequent falling. The microscopic examination of brain and spinal cord tissues from two affected sheep revealed mild vacuolation, occasional lymphocytic cuffing around blood vessels, mild Wallerian degeneration, and occasional glial cells that contained honey-brown cytoplasmic pigments. The most significant changes were found in the cerebellum, where there were decreased numbers of Purkinje cells, increased numbers of glial cells, scattered vacuoles and occasional swollen axons. Previous reports of cerebellar toxicoses in ruminants have involved goats and cattle and have been associated with the ingestion of six Solanum spp. The Purkinje cell loss in this type of disorder is ultimately extensive and consequently affected animals may survive, but will remain permanently disabled.

Clinical manifestation of focal cerebellar disease as related to the organization of neural pathways

Neural pathways connect different parts of the cerebellum to different parts of the central nervous system. The cerebellum may be divided anatomically and functionally into three major regions. The cerebellar hemispheres and a small part of the posterior lobe vermis form the pontocerebellum, which receives inputs from the cerebral cortex via the pontine nuclei. The anterior lobe and most of the posterior lobe vermis make up the spinocerebellum, which receives afferents from the spinal cord. The nodulus and flocculus are connected with the vestibular nuclei and constitute the vestibulocerebellum. Most cases of cerebellar disease affect more than one region and different pathways. Hence, they cause generalized cerebellar symptoms dominated by impaired motor control and balance. Focal syndromes after restricted cerebellar lesions are rare. Isolated spinocerebellar affection may give gait ataxia. Vestibulocerebellar disease causes equilibrium disturbances with truncal ataxia and nystagmus. Pontocerebellar lesions typically give ipsilateral limb ataxia, but also dysartria and oculomotor dysfunction if vermal parts are involved. The clinical picture is in most cases of cerebellar disease dominated by motor disturbances, but the cerebellum also participates in the modulation of autonomic and affective responses and in cognitive functions. The cerebrocerebellar and hypothalamocerebellar circuits may be important for these tasks.