scholarly journals The Relationship between Neuropsychological Performance and Level of Direct Current Potential in Patients with Occupational Diseases from Exposure to Physical Factors

2021 ◽  
Vol 6 (1) ◽  
pp. 94-100
Author(s):  
O. I. Shevchenko ◽  
O. L. Lakhman
Keyword(s):  
Direct Current ◽  
Occupational Diseases ◽  
Group Iv ◽  
Physical Factors ◽  
Group Iii ◽  
Dc Potential ◽  
Constant Potential ◽  
The Brain ◽  
Current Potential ◽  
Potential Level

The aim of the study was to identify the peculiarities of neuropsychological indices disorders depending on changes in the level of constant potential in patients with occupational diseases as a result of physical factors.Materials and methods. The study involved 60 patients with vibration disease caused by local vibration (group I), 106 patients with vibration disease caused by combined exposure to local and general vibration (group II), 101 civil aviation pilots with an established diagnosis of professional sensorineural hearing loss (group III), and 50 healthy men (group IV, comparison group) who were not exposed to vibration and noise due to the specifics of their professional activities. Methods of neuro-energy mapping and neuropsychological testing were used.Results. In groups I–II, compared with group IV, an increase in local levels of constant potential (DC-potential level) in the central, right temporal, and central frontal parts of the brain (2.3 (6.5–3.8) mV; –0.3 (–2.1–2.1); 2.1 (–3.4–6.8) and –0.3 (–3.1–4.3); –2.24 (–6.4–3.8); 0.9 (–3.1–8.5) mV at p = 0.005, 0.007 and 0.004 respectively). Differences in the values of DC-potential level gradients in individuals of group III when compared with group IV reached the level of significance in the central, temporal, occipital leads relative to the central frontal (–5.0 (–13.1–3.8); –4.1 (–9.4–5.1); –2.1 (–10.9–6.6); –6.3 (–15.3–1.8) and 2.9 (–3.0–10.6); 2.2 (–4.5–13.8); 5.6 (–7.6–14.1); –1.4 (–7.5–3.9) mV at p = 0.008; 0.009; 0.009, and 0.007 respectively). Cognitive disorders in patients of groups I–III when compared with group IV correspond to a mild disorder of dynamic, constructive praxis and expressive speech (1.40 (0–1,6); 1.43 (0–1,7); 1.2 (0–1,5) and 0.3 (0–1); 0.2 (0–1); 0.06 (0–1) points at p = 0.008, 0.008 and 0.009 respectively).Conclusions. A common neurofunctional sign of a mild impairment of the cognitive sphere in occupational diseases caused by physical factors is an increase in direct current potential level in the frontal-central and parieto-occipital regions, predominantly of the left hemisphere of the brain.

Evidence that beta 2-receptors mediate action of catecholamines on endolymphatic sac DC potential

1991 ◽  
Vol 260 (5) ◽  
pp. R911-R915 ◽  
Author(s):  
N. Mori ◽  
N. Uozumi
Keyword(s):  
Direct Current ◽  
Adrenergic Receptors ◽  
Endolymphatic Sac ◽  
Beta Adrenergic Receptors ◽  
Beta Adrenergic ◽  
Selective Antagonist ◽  
Dc Potential ◽  
Beta 2 ◽  
Current Potential

Our recent study has revealed that catecholamines depress the endolymphatic sac direct current potential (ESP) by the beta-adrenergic action [Mori et al., Am. J. Physiol. 259 (regulatory Integrative Comp. Physiol. 28): R921-R924, 1990]. Beta-Adrenergic receptors have been subclassified into beta 1- and beta 2-receptors. Using beta 1-selective (dobutamine) and beta 2-selective (salbutamol) agonists and a beta 1-selective antagonist (atenolol), we determined the subtype of beta-adrenergic receptors that mediate the action of catecholamines on the ESP. Salbutamol depressed the ESP to a larger degree than dobutamine [34.0 +/- 2.6 (n = 7) vs. 13.0 +/- 2.0% (n = 8)] with a much lower dose (100 vs. 1,000 micrograms/kg). Atenolol failed to block the action of salbutamol on the ESP at a dose of 1 mg/kg, whereas propranolol inhibited it at the same dose. The results indicate that beta 2-receptors mediate the action of catecholamines on the ESP.

Effects of Furosemide and Ethacrynic Acid on The Endocochlear Direct Current Potential in Normal and Kanamycin Sulfate-Treated Guinea Pigs

1980 ◽  
Vol 88 (2) ◽  
pp. 188-193 ◽  
Author(s):  
Shinichiro Asakuma ◽  
James B. Snow
Keyword(s):  
Direct Current ◽  
Electrical Resistance ◽  
Guinea Pigs ◽  
Ethacrynic Acid ◽  
Loop Diuretics ◽  
Control Group ◽  
Kanamycin Sulfate ◽  
Dc Potential ◽  
Cochlear Partition ◽  
Current Potential

The effects of loop diuretics on the endocochlear direct current (DC) potential and the effective electrical resistance of the cochlear partition were studied. The effective electrical resistance was increased, and the endocohlear DC potential was decreased. The decrease in the endocohlear DC potential must not be caused by breaks in the electrical insulation of the cochlear partition. With loop diuretics the endocochlear DC potential decreased less in guinea pigs treated with kanamycin sulfate than it did in the control group. Two interpretations of these phenomena are presented.

Diagnosis and management of pediatric brain-stem gliomas

1986 ◽  
Vol 65 (6) ◽  
pp. 745-750 ◽  
Author(s):  
Ann R. Stroink ◽  
Harold J. Hoffman ◽  
E. Bruce Hendrick ◽  
Robin P. Humphreys
Keyword(s):  
Brain Stem ◽  
Survival Time ◽  
Group Iv ◽  
Content Type ◽  
Group Iii ◽  
Mean Survival Time ◽  
Group I ◽  
Group Ii ◽  
The Brain

✓ The authors reviewed the cases of 49 children, ranging in age from 9 months to 15 years, who were diagnosed by computerized tomography (CT) as having brain-stem glioma. Four distinct groups of brain-stem gliomas were identified based on CT scan characteristics: Group I included isodense contrast-enhancing tumors that were dorsally exophytic into the fourth ventricle; Group II(a) included hypodense nonenhancing intrinsic tumors of the brain stem; Group II(b) included intrinsic tumors of the brain stem with hyperdense exophytic components extending ventrally and laterally into the cerebellopontine and prepontine cisterns; Group III included intrinsic cystic tumors with contrast-enhancing capsules; and Group IV included focally intrinsic tumors of the brain stem that were isodense and enhanced brightly on administration of contrast medium. The clinical presentation, efficacy of surgical intervention, pathology, and prognosis of these tumors were correlated within these groupings. Eleven patients had Group I tumors, all of which were surgically resected; 10 of the 11 lesions were proven to be low-grade gliomas. These patients had an excellent prognosis; 10 of the 11 survived, with a mean follow-up period of 4.5 years. There were 18 patients with Group II(a) tumors; although tumor biopsy was attempted on eight of these, pathological diagnosis at the time of surgery was made in only one case. These patients did poorly; the mean survival time was 6.2 months. The seven Group II(b) tumor patients demonstrated a similarly poor prognosis: all of them died within 23 months of diagnosis, with a mean survival time of 12 months. Only two of six patients undergoing biopsy had sufficient tissue for histological verification. Three of the four patients with Group III tumors died; their mean survival time was 11.5 months. Successful histological examination was carried out in all four cases. The nine Group IV tumor patients did reasonably well; seven of these patients remain alive, with a mean follow-up period of 2.3 years. Histological diagnosis was obtained in three of the seven patients who were explored in this group. This classification system has proven to be of value in determining prognosis and efficacy of surgical intervention.

scholarly journals EVALUATION OF THE PROPHYLACTIC ROLE OF INDIAN SHRIMP IN ALUMINUM CHLORIDE-INDUCED ALZHEIMER’S DISEASE ON EXPERIMENTAL RATS

2019 ◽  
pp. 377-382
Author(s):  
RAMACHANDRAN S ◽  
SRI RAMYA M ◽  
LIZA U ◽  
LAKSHMI PRASANNA PS ◽  
SARISHMA K
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Aluminum Chloride ◽  
Group Iv ◽  
Group V ◽  
Group Iii ◽  
Group I ◽  
Male Wistar Rats ◽  
The Brain

Objective: This work was aimed to investigate the prophylactic and therapeutic role of Indian shrimp in aluminum chloride-induced Alzheimer’s disease (AD) in rats. Methods: The male Wistar rats were selected and divided into six groups. Group I received distilled water, Group II received AlCl3 ( 100 mg/kg, p.o.), Group III received rivastigmine (1 mg/kg, p.o.), Group IV received AlCl3 + shrimp powder (200 mg/kg, p.o), and Group V received AlCl3 + shrimp powder (400 mg/kg, p.o) for 60 days. At the end of the study, various parameters such as behavioral and biochemical investigations were assessed. Results: The result of the study shows that the shrimp (400 mg/kg) has better effect on the treatment of aluminum chloride-induced AD in rats. It showed a remarkable improvement in the behavioral and biochemical parameters, and the result of histopathology study shows that the hippocampus region of brain tissue recovered as compared with control. Conclusion: From this study, it is evident that dietary intake of shrimp can help to inhibit oxidative stress produced due to the accumulation of AlCl3 in the brain and used as a prophylactic for AD.

scholarly journals Infarct Rim: Effect of Hyperglycemia on Direct Current Potential and [14C]2-Deoxyglucose Phosphorylation

1986 ◽  
Vol 6 (5) ◽  
pp. 607-615 ◽  
Author(s):  
Maiken Nedergaard ◽  
Jens Astrup
Keyword(s):  
Middle Cerebral Artery ◽  
Direct Current ◽  
Spreading Depression ◽  
Focal Ischemia ◽  
Extracellular Potassium ◽  
Tissue Area ◽  
Dc Potential ◽  
Potassium Application ◽  
The Right ◽  
Current Potential

Focal ischemia was produced by occlusion of the right middle cerebral artery (MCA) in normo- and hyperglycemic rats. In the cortical infarct rim, regional [14C]2-deoxyglucose ([14C]2-DG) phosphorylation was correlated to spontaneous transient changes in extracellular potassium recorded as direct current (DC) potential deflections. In normoglycemic rats the DC potential showed transient but recurrent deflections in the first hours following MCA occlusion. The 2-DG phosphorylation was elevated by 200% in the same area. In contrast, hyperglycemic rats had no, or a single, deflection of the DC potential in the rim, and the 2-DG phosphorylation remained normal. The same pattern was obtained by application of 3 M KCl to the exposed cortex. In normoglycemia potassium application resulted in recurrent deflections of the DC potential, and 2-DG phosphorylation increased in most parts of the hemisphere. Hyperglycemic animals had a nearly stable DC potential, and 2-DG phosphorylation increased only in the tissue area situated directly below the site of potassium application. The results indicate that metabolism in the cortical infarct rim is stimulated by spontaneous and recurrent changes in extracellular potassium—a phenomenon that may be related to spreading depression—and that the metabolism remained normal in the same area in hyperglycemic animals owing to an inhibition of transient increases of extracellular potassium.

RATIO OF TOTAL SLOW AND SUPER SLOW CEREBRAL BIOELECTRICAL ACTIVITY IN CHILDREN WITH HYPOXIA

2021 ◽  
pp. 123-131
Author(s):  
A.B. Ivanov ◽  
I.Kh. Borukaeva ◽  
A.A. Molov ◽  
Z.Kh. Abazova ◽  
K.Yu. Shkhagumov
Keyword(s):  
Brain Activity ◽  
Simultaneous Increase ◽  
Adaptation To Hypoxia ◽  
Bioelectrical Activity ◽  
Electrical Brain Activity ◽  
Delta Activity ◽  
The Central Nervous System ◽  
Constant Potential ◽  
The Brain ◽  
Potential Level

The aim of the study is to identify changes in the total slow and super slow bioelectric activity of the cerebral hemispheres in 8–11-year-old children under reduced oxygen partial pressure in the inhaled air and in norm. Materials and Methods. The authors examined 82 8–11-year-old children. EEG registration was carried out on a complex Russian device "Telepat-103" with computer processing of the results. Slow potentials were recorded using a special computer complex for studying constant potential level (CPL) and cerebral energy consumption "Neuroenergon". Hypoxia was created by a special medical device "Hypoxicator" (Trade Medical). The choice of the oxygen content in the test hypoxic mixture (14 % O2) was based on the results of a three-stage hypoxic test carried out before the complex examination. Results. Hypoxia increases the index and amplitude of delta oscillations and decreases the number of alpha waves in 8–11-year-old children. The results obtained indicate that it is more important to provide the brain with a sufficient amount of oxygen corresponding to its needs than simply to increase the brain blood supply during hypoxia. The study also indicates the contribution of the body's sensitivity to hypoxic response. Under hypoxia, an increase in the constant potential level in the studied brain areas is observed in 8–11-year-old children. An increase in electrical activity during normobaric hypoxia is noted at low baseline values of constant potential level. An increase in the slow electrical brain activity occurs due to the change of brain energy supply according to the biochemical indicators of energy metabolism. Short-term hypoxia is accompanied by a simultaneous increase in slow-wave activity due to delta activity and CPL in 8–11-year-old children. Conclusion. Thus, we can say that a picture of functional brain activity with simultaneous inhibitory phenomena in the cortex is formed. It may reflect the development of a special state of the central nervous system. Key words: constant potential level, electroencephalography, hypoxia, adaptation to hypoxia. Цель работы – выявление изменений суммарной медленной и сверхмедленной биоэлектрической активности полушарий головного мозга у детей в возрасте от 8 до 11 лет в условиях нормального и сниженного парциального давления кислорода во вдыхаемом воздухе. Материалы и методы. Обследовано 82 ребенка 8–11-летнего возраста. Регистрация ЭЭГ осуществлялась на комплексной отечественной установке «Телепат-103» с компьютерной обработкой результатов. Медленные потенциалы фиксировались с помощью специального компьютерного комплекса для исследования уровня постоянных потенциалов (УПП) и энергозатрат головного мозга «Нейроэнергон». Гипоксические условия создавались аппаратом «Гипоксикатор» фирмы Trade Medical. Выбор содержания кислорода в тестирующей гипоксической смеси (14 % О2) основывался на результатах проведенного до комплексного обследования трехступенчатого гипоксического теста. Результаты. У детей от 8 до 11 лет действие гипоксии на головной мозг приводит к возрастанию индекса и амплитуды дельта-колебаний и убыванию числа альфа-волн. Полученные результаты говорят о том, что большое значение имеет не столько усиление кровоснабжения головного мозга при гипоксии, сколько обеспечение мозга достаточным, соответствующим его потребностям, количеством кислорода, а также о роли чувствительности организма к гипоксии. При воздействии гипоксии у детей этого возраста наблюдается возрастание уровня постоянных потенциалов в исследуемых областях головного мозга. При низких фоновых значениях уровня постоянных потенциалов отмечается возрастание электрической активности при нормобарической гипоксии. Возрастание медленной электрической активности головного мозга происходит из-за того, что изменяется энергообеспечение головного мозга по биохимическим показателям энергетического обмена. Действие кратковременной гипоксии сопровождается одновременным возрастанием медленноволновой активности за счет дельта-активности и УПП у детей от 8 до 11 лет. Выводы. Таким образом, можно говорить о том, что формируется своеобразная картина функциональной активности с одновременными тормозными явлениями в коре, что может являться отражением развития особого состояния центральной нервной системы. Ключевые слова: уровень постоянных потенциалов, электроэнцефалография, гипоксия, адаптация к гипоксии.

Effects of Furosemide and Ethacrynic Acid on the Endocochlear Direct Current Potential in Normal and Kanamycin Sulfate-Treated Guinea Pigs

1980 ◽  
Vol 88 (2) ◽  
pp. 188-193 ◽  
Author(s):  
Shinichiro Asakuma ◽  
James B. Snow
Keyword(s):  
Direct Current ◽  
Electrical Resistance ◽  
Guinea Pigs ◽  
Ethacrynic Acid ◽  
Loop Diuretics ◽  
Control Group ◽  
Kanamycin Sulfate ◽  
Dc Potential ◽  
Cochlear Partition ◽  
Current Potential

The effects of loop diuretics on the endocochlear direct current (DC) potential and the effective electrical resistance of the cochlear partition were studied. The effective electrical resistance was increased, and the endocohlear DC potential was decreased. The decrease in the endocohlear DC potential must not be caused by breaks in the electrical insulation of the cochlear partition. With loop diuretics the endocochlear DC potential decreased less in guinea pigs treated with kanamycin sulfate than it did in the control group. Two interpretations of these phenomena are presented.

Analysis of surface conditioning methods on core-veneer bond strength of CAD/CAM zirconia restorations

2020 ◽  
pp. 1-11
Author(s):  
Anip K. Roy ◽  
Govind N. Prasad ◽  
Tushar V. Bhagat ◽  
Saurabh Chaturvedi ◽  
Vishwanath Gurumurthy ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Group Iv ◽  
Control Group ◽  
Group Iii ◽  
Surface Conditioning ◽  
Group I ◽  
Alumina Particles ◽  
Scanning Electron

BACKGROUND: The increased strength of zirconia has resulted in its widespread application in clinical dentistry. Nevertheless, the fracture of veneering porcelains remains one of the key reasons of failure. OBJECTIVE: The objective of this study was to compare and analyze the influence of surface conditioning methods on the core-veneer bond strength of zirconia restorations. METHODS: Thirty specimens of zirconia core with sizes 10 × 5 × 5 mm were layered with porcelain of sizes 5 × 3 × 3 mm. On the basis of different surface conditioning methods, four groups were made: Group I: abrasion with airborne alumina particles of 110 μm size, Group II: sandblasting with silica coated alumina particles of 50 μm in size, Group III (modified group): alteration with a coating of zirconia powder prior to sintering, and Group IV (control group): metal core specimens. The shear force of all specimens was tested using a universal testing machine with a 0.5 mm/min crosshead speed. One-way analysis of variance (ANOVA) and Tukey’s post hoc pair wise comparison (p= 0.05) were performed to analyze the shear bond strength. A scanning electron microscope was used to assess the fractured specimens. RESULTS: A statistically significant difference was noted between the groups. The mean value of shear bond strength was 40.25 MPa for Group I, 41.93 MPa for Group II, 48.08 MPa for Group III and 47.01 MPa for Group IV. CONCLUSIONS: The modified zirconia group and control group demonstrated a significantly higher mean bond strength than that of Group I, where airborne particle abrasion was used. The scanning electron microscope showed that cohesive fracture in the porcelain veneers was the main problem of failure in altered zirconia. The modified zirconia specimens in Group III demonstrated significantly improved values of shear bond strength.

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