Physiological changes in human erythrocyte cholinesterase as measured with the "pH-stat".

Abstract Cholinesterase activity in human erythrocytes was determined in 1903 blood samples by the "pH-stat" method. Differences in activity were examined as a function of sex, age, and pregnancy. Reliability intervals for the population average and approval or normality intervals for individual values were established. Sex- and age-related differences were very significant.

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Elemental analysis of human erythrocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015318x ◽

1989 ◽

Vol 47 ◽

pp. 242-243

Author(s):

S. A. Livesey ◽

A. A. del Campo ◽

E. S. Griffey ◽

D. Ohlmer ◽

T. Schifani ◽

...

Keyword(s):

Sample Preparation ◽

Elemental Analysis ◽

Human Erythrocyte ◽

Spectroscopic Analysis ◽

Model System ◽

Human Erythrocytes ◽

List Type ◽

Chemical Fixation ◽

Ethanol Dehydration ◽

Lowicryl K4m

The aim of this study is to compare methods of sample preparation for elemental analysis. The model system which is used is the human erythrocyte. Energy dispersive spectroscopic analysis has been previously reported for cryofixed and cryosectioned erythrocytes. Such work represents the reference point for this study. The use of plastic embedded samples for elemental analysis has also been documented. The work which is presented here is based on human erythrocytes which have been either chemically fixed and embedded or cryofixed and subsequently processed by a variety of techniques which culminated in plastic embedded samples.Heparinized and washed erythrocytes were prepared by the following methods for this study :(1). Chemical fixation in 4% paraformaldehyde/0.25% glutaraldehyde/0.2 M sucrose in 0.1 M Na cacodylate, pH 7.3 for 30 min, followed by ethanol dehydration, infiltration and embedding in Lowicryl K4M at -20° C.

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IN VITRO UPTAKE OF RADIOACTIVE 131I LABELLED L-TRIIODOTHYRONINE BY HUMAN ERYTHROCYTES AS AN INDEX OF THYROID FUNCTION

Acta Endocrinologica ◽

10.1530/acta.0.xxxiv0305 ◽

1960 ◽

Vol XXXIV (II) ◽

pp. 305-311 ◽

Cited By ~ 3

Author(s):

M. G. Woldring ◽

A. Bakker ◽

H. Doorenbos

Keyword(s):

Thyroid Function ◽

Incubation Time ◽

Clinical Results ◽

Human Erythrocytes ◽

Red Cell ◽

Clinical Value ◽

Blood Samples ◽

In Vitro Uptake

ABSTRACT The red cell triiodothyronine uptake technique as used in our hospital is described. Incubation time is of almost no importance. The temperature during incubation should be 37° C. Further improvement of the technique is obtained when all blood samples are brought up to 40 % haematocrit prior to incubation. Clinical results are discussed. It is yet too early to give a definite assessment of its clinical value, but it is definitely superior to the measurement of the BMR.

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Cholinesterase Activities and Oxidative Stress in Cattle Experimentally Exposed to Nitrate/Nitrite in Cultivated Pasture with Different Fertilization Schemes

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.82068 ◽

2018 ◽

Vol 46 (1) ◽

Author(s):

Ricardo Christ ◽

Aleksandro Schafer Da Silva ◽

Mateus Eloir Grabriel ◽

Luan Cleber Henker ◽

Renan Augusto Cechin ◽

...

Keyword(s):

Oxidative Stress ◽

Enzyme Activity ◽

Cholinesterase Activity ◽

Blood Samples ◽

Group 3 ◽

Cholinesterase Activities ◽

Group 2 ◽

Nitrate And Nitrite ◽

And Oxidative Stress ◽

Group 1

Background: Nitrate and nitrite poisoning is associated with pasture intake that has high nitrate levels and leads to acute methemoglobinemia. Pasture may accumulate nitrate under certain conditions, such as excessively fertilized soil or environmental conditions that enhance the N absorption (rain preceded by a period of drought). After ingestion of plants, this substrate reaches the rumen and, in physiological conditions, is reduced to nitrite and afterward to ammonia. The aim of this study was to evaluate changes in cholinesterase activities and oxidative stress caused by subclinical poisoning for nitrate and nitrite in cattle fed with Pennisetum glaucum in three different fertilization schemes. Materials, Methods & Results: In order to perform the experimental poisoning, the pasture was cultivated in three different paddocks: with nitrogen topdressing (urea; group 1), organic fertilizer (group 2) or without fertilizer (group 3; control). Nitrate accumulation in forage was evaluated by the diphenylamine test. After food fasting of 12 h, nine bovine were randomly allocated to one of the experimental groups and fed with fresh forage (ad libitum) from respective paddock. In different time points from beginning of pasture intake (0, 2, 4, 6 and 9 h) heart rate and respiratory frequency were assessed, as well as mucous membrane color and behavioral changes. Blood samples from jugular vein into vials with and without anticoagulant were collected. From blood samples, serum nitrite levels, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme activity were evaluated, as well as oxidative stress through the following parameters: levels of nitrate/nitrite (NOx), thiobarbituric acid reactive substances (TBARS) and reactive oxygen species (ROS), beyond the antioxidant system by enzyme activity measurement of catalase (CAT) and superoxide dismutase (SOD). The diphenylamine test was positive to group 1 and 2, so that the pasture presented 3.16 mg/kg, 2.98 mg/kg and 1.67 mg/kg of nitrate for group 1, 2 and 3, respectively. In addition, cows from group 1 demonstrated increased (P < 0.05) nitrite levels in serum, compared to other groups, and greater heart rate after 9 h (P < 0.05). The AChE and BChE activity in group 1 showed significant increase (P < 0.05) at 4 and 6 h (AChE), and 4 and 9 h (BChE) compared to group 3. Also, NOx levels were lower at 6 and 9 h (P < 0.05) and at 9 h (P < 0.05) for animals of group 1 and 2, respectively, when compared to group 3. Furthermore, in the group 1 levels of ROS and TBARS were significantly higher (P < 0.05) after 2 and 4 h, and 6 and 9 h compared to other groups, respectively. The CAT activity increased significantly (P < 0.05) with 2 and 4 h of the experiment, but on the other hand, decreased at 6 and 9 h in group 1. Nevertheless, the animals from group 2 presented only a significant reduction in this enzyme activity at 9 h. Furthermore, SOD activity was reduced in animals of groups 1 (P < 0.05) at 4, 6 and 9 h, compared to other groups. Discussion: It was concluded that the nitrate and nitrite poisoning by pasture intake cultivated and fertilized with urea leads to increased levels of serum nitrite, as well as the cholinesterase activity and causes oxidative stress in cattle. It is conjectured that the cholinesterase activity and oxidative stress may assist in understanding the pathophysiology of changes caused by poisoning.Keywords: plant toxicology, poisoning, methemoglobin, cholinergic system, oxidative stress.

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Corticobasal Degeneration Misdiagnosed As Musculoskeletal Disease: A Challenging Diagnosis of Higher-Level Gait Disease

Journal of Neurosciences in Rural Practice ◽

10.1055/s-0040-1716773 ◽

2020 ◽

Vol 11 (04) ◽

pp. 640-642

Author(s):

Halil Onder

Keyword(s):

Corticobasal Degeneration ◽

The Elderly ◽

Gait Disorders ◽

Physiological Changes ◽

Gait Abnormality ◽

Age Related ◽

Musculoskeletal Problems ◽

Neurological Exam ◽

Long Time ◽

High Level

AbstractGait disorders are common in the elderly as there are various causes of neurological and non-neurological conditions. On the other hand, most of the gait parameters do change with advancing age which is identified as age-related physiological changes in gait. At this point, the discrimination between age-related physiological changes and gait disorders may be strictly challenging. After identifying gait as an abnormal pattern, classification of it and making the responsible pathophysiology also require high-level expertise in this regard. Herein, we present a rare patient with corticobasal degeneration (CBD) who had admitted initially due to complaints of gait problems. Over a long time, the patient had received the misdiagnosis of gait abnormality due to musculoskeletal problems by multiple physicians. However, the detailed neurological exam showed a higher level gait disorder (HLGD). Further investigations at this point yielded the diagnosis of CBD.

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Lead and calcium transport in human erythrocyte

Human & Experimental Toxicology ◽

10.1191/096032799678840138 ◽

1999 ◽

Vol 18 (5) ◽

pp. 327-332 ◽

Cited By ~ 14

Author(s):

J V Calderón-Salinas ◽

M A Quintanar-Escorcia ◽

M T González-Martínez ◽

C E Hernández-Luna

Keyword(s):

Transport System ◽

Human Erythrocyte ◽

Calcium Transport ◽

Human Erythrocytes ◽

The Other ◽

Erythrocyte Ghosts ◽

Passive Transport ◽

Ca Uptake

In this paper we report the lead (Pb) and calcium (Ca) uptake by erythrocyte ghosts. In both cases the transport was carried out by a passive transport system with two kinetic components (Michaelis-Menten and Hill). Pb and Ca were capable of inhibiting the transport of the other metal in a non-competitive way. Under hyperpolarization, the uptakes of Ca and Pb were enhanced and the Michaelis-Menten component prevailed. Both Ca and Pb uptakes were inhibited by N-ethyl-maleimide to the same extent. These results indicate that Pb and Ca share the same permeability pathway in human erythrocytes and that this transport system is electrogenic.

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A carbohydrate-deficient membrane glycoprotein in human erythrocytes of phenotype S-s-

Biochemical Journal ◽

10.1042/bj1650157 ◽

1977 ◽

Vol 165 (1) ◽

pp. 157-161 ◽

Cited By ~ 23

Author(s):

M J A Tanner ◽

D J Anstee ◽

P A Judson

Keyword(s):

Blood Group ◽

Arachis Hypogaea ◽

Human Erythrocyte ◽

Structure And Function ◽

Human Erythrocytes ◽

Erythrocyte Membranes ◽

Membrane Glycoprotein ◽

Blood Group Antigens ◽

And Function ◽

Normal Erythrocyte

1. We investigated the membranes of human erythrocytes which completely lack the blood-group antigens S and s (denoted as S-s-) as part of a study of the structure and function of the surface glycoproteins of the human erythrocyte. 2. The S-s-erythrocyte-membrane glycoprotein PAS-3 band was much less intensely stained in comparison with that of the glycoprotein from normal erythrocyte membranes. The S-s-membrane glycoprotein PAS-4 band also showed decreased staining. 3. Examination with the lectins from Maclura aurantiaca (Osage orange) and Arachis hypogaea (groundnut) showed that the PAS-3 glycoprotein of S-s-erythrocyte membranes lacked the receptors for these lectins that are present on glycoprotein PAS-3 from normal erythrocytes. 4. Radioiodination with lactoperoxidase showed the presence of the polypeptide of glycoprotein PAS-3 in S-s-cells, although it was more weakly labelled than the protein in the normal erythrocyte. 5. Our results show that the PAS-3 glycoprotein of S-s-erythrocytes is deficient in some of the carbohydrates present in the protein from normal erythrocytes. Glycoprotein PAS-4 of normal erythrocytes is shown to be a complex containing both glycoproteins PAS-1 and PAS-3.

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Kinetics and Mechanism of Hydrolysis of Acetylthiocholine by Butyrylcholine Esterase

Zeitschrift für Naturforschung C ◽

10.1515/znc-2002-11-1221 ◽

2002 ◽

Vol 57 (11-12) ◽

pp. 1072-1077 ◽

Cited By ~ 4

Author(s):

Karel Komers ◽

Alexandr Čegan ◽

Marek Link

Keyword(s):

Acetic Acid ◽

Kinetics And Mechanism ◽

Kinetics Parameters ◽

Mechanism Of Hydrolysis ◽

Ph Stat ◽

Stat Method ◽

Ellman’S Method ◽

Hydrolysis Of

Kinetics and mechanism of hydrolysis of acetylthiocholine by the enzyme butyrylcholine esterase was studied. The spectrophotometric Ellman’s method and potentiometric pH-stat method were used for continuous determination of the actual concentration of the products thiocholine and acetic acid in the reaction mixture. The validity of the Michaelis-Menten (Briggs-Haldane) equation in the whole course of the reaction under used conditions was proved. The corresponding kinetics parameters (Vm and KM) were calculated from the obtained dependences of concentration of thiocholine or acetic acid vs. time and compared. From this comparison the deciding kinetic role of the step producing thiocholine was derived. The values of initial molar concentration of the enzyme and of the rate constants of the kinetic model were estimated.

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Bicarbonate Transport Systems in the Intestine of the Seawater EEL

Journal of Experimental Biology ◽

10.1242/jeb.150.1.381 ◽

1990 ◽

Vol 150 (1) ◽

pp. 381-394 ◽

Cited By ~ 8

Author(s):

MASAAKI ANDO ◽

M. V. SUBRAMANYAM

Keyword(s):

Latent Period ◽

Water Transport ◽

Basolateral Membrane ◽

Transport Systems ◽

Bicarbonate Transport ◽

Ph Stat ◽

Stat Method

Utilizing a pH-stat method, the rates of mucosal and serosal alkalinization were measured separately in the seawater eel intestine. These two rates were dependent on contralateral HCO3− concentration and were inhibited by contralateral application of DIDS, an inhibitor of HCO3− transport, indicating that the mucosal and serosal alkalinization are due to HCO3− secretion and absorption, respectively. The mucosal alkalinization was enhanced after inhibiting Na+/K+/Cl− cotransport by treatment with bumetanide, furosemide or Ba2+, with a latent period of more than lOmin, suggesting that HCO3− absorption from mucosa to serosa depends on Na+/K+/Cl− cotransport. The serosal alkalinization caused by HCO3− absorption was completely abolished after mucosal application of bumetanide. After pretreatment with bumetanide, mucosal omission of Cl− halved the enhanced rate of mucosal alkalinization, and Na+ omission had no effect on it; this indicates that the exit of HCO3− into the lumen depends on luminal Cl−, i.e. on the existence of the usual C1−/HCO3− exchange on the brushborder membrane. When serosal Na+ was removed under the same conditions, mucosal alkalinization was reduced, indicating that HCO3− entry from the serosal fluid depends on Na+. Serosal omission of Cl− did not reduce mucosal alkalinization. In addition, serosal alkalinization was enhanced by serosal removal of Na+ but not of Cl−. These results suggest that there is a Na+/HCO3− cotransport on the basolateral membrane. A possible model for HCO3− transport systems in the seawater eel intestine is proposed, and a possible role for these transport systems is discussed in relation to Na+, Cl− and water transport.

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Syncope and neurocardiovascular instability

Oxford Textbook of Geriatric Medicine ◽

10.1093/med/9780198701590.003.0102 ◽

2017 ◽

pp. 783-792

Author(s):

Rose Anne Kenny ◽

Conal Cunningham

Keyword(s):

Vasovagal Syncope ◽

Sinus Node ◽

Physiological Changes ◽

Younger Patients ◽

Dual Pathology ◽

Age Related ◽

Common Causes ◽

Node Disease ◽

Sinus Node Disease ◽

High Index Of Suspicion

The prevalence of syncope rises with age and is challenging because of atypical presentation, overlap with falls, and poor recall of events. Cardiac causes and multiple comorbidities are more common, and related morbidity and mortality are higher than in younger patients. Hence, a high index of suspicion for cardiovascular causes of falls and dual pathology will increase successful diagnosis and intervention. Age-related neurohumoral and physiological changes plus chronic diseases and medications often contribute to syncope. Orthostatic hypotension, carotid sinus syndrome, vasovagal syncope, postprandial syncope, sinus node disease, atrioventricular block, and ventricular tachycardia are other common causes. Management is often based on removing or reducing the predisposing or precipitating factors through medication adjustments, behavioural strategies, and more invasive cardiac interventions if indicated. It is often not possible to identify a single cause of syncope in older persons, hence apragmatic management of each diagnosis is recommended.

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