Enzymic measurement of urinary pyrophosphate with a centrifugal analyzer.

1982 ◽  
Vol 28 (1) ◽  
pp. 134-137 ◽  
Author(s):  
J B Roullet ◽  
B Lacour ◽  
A Ulmann ◽  
M Bailly
Keyword(s):  
Coefficient Of Variation ◽  
Healthy Subjects ◽  
High Sensitivity ◽  
Inhibitory Effect ◽  
Mean Value ◽  
Good Reproducibility ◽  
Combined System ◽  
Phosphate Ions ◽  
The Mean ◽  
Automated Technique

Abstract We describe a simple, rapid, and fully automated technique for measuring urinary pyrophosphates with a centrifugal analyzer (the ENI GEMSAEC). This technique depends on the enzymic magnesium-dependent reaction with UDPG pyrophosphorylase (UTP: alpha-D-glucose-1-phosphate uridylyl transferase, EC 2.7.7.9) and spectrophotometry of the NADPH formed in a combined system of phosphorylation and reduction. Many samples of urine can be analyzed quickly without pretreatment, with high sensitivity (1.3 mA/mumol of substrate) and good reproducibility. The mean within-run coefficient of variation for a 50 mumol/L pyrophosphate solution was 1.4%. We determined the optimum enzyme and magnesium concentrations necessary for use in a 4-min reaction. Because there is no inhibitory effect of chloride and phosphate ions, pyrophosphate can be measured directly in urine, without prior extraction. With this technique, the mean value (and SD) for urinary pyrophosphate excretion by 30 healthy subjects was 39.3 (SD 17.2) mumol/24 h.

scholarly journals Branching exponent heterogeneity and wall shear stress distribution in vascular trees

2001 ◽  
Vol 280 (3) ◽  
pp. H1256-H1263 ◽  
Author(s):  
Kelly L. Karau ◽  
Gary S. Krenz ◽  
Christopher A. Dawson
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Coefficient Of Variation ◽  
Vessel Diameter ◽  
Mean Value ◽  
Heterogeneous Distribution ◽  
Uniform Shear ◽  
The Mean ◽  
Wall Shear ◽  
Stress Dependent

A bifurcating arterial system with Poiseuille flow can function at minimum cost and with uniform wall shear stress if the branching exponent ( z) = 3 [where z is defined by ( D 1) z = ( D 2) z + ( D 3) z ; D 1 is the parent vessel diameter and D 2 and D 3 are the two daughter vessel diameters at a bifurcation]. Because wall shear stress is a physiologically transducible force, shear stress-dependent control over vessel diameter would appear to provide a means for preserving this optimal structure through maintenance of uniform shear stress. A mean z of 3 has been considered confirmation of such a control mechanism. The objective of the present study was to evaluate the consequences of a heterogeneous distribution of z values about the mean with regard to this uniform shear stress hypothesis. Simulations were carried out on model structures otherwise conforming to the criteria consistent with uniform shear stress when z = 3 but with varying distributions of z. The result was that when there was significant heterogeneity in z approaching that found in a real arterial tree, the coefficient of variation in shear stress was comparable to the coefficient of variation in z and nearly independent of the mean value of z. A systematic increase in mean shear stress with decreasing vessel diameter was one component of the variation in shear stress even when the mean z = 3. The conclusion is that the influence of shear stress in determining vessel diameters is not, per se, manifested in a mean value of z. In a vascular tree having a heterogeneous distribution in zvalues, a particular mean value of z (e.g., z = 3) apparently has little bearing on the uniform shear stress hypothesis.

scholarly journals Serum Adenosine Deaminase Values in Healthy People

2020 ◽  
Keyword(s):  
Adenosine Deaminase ◽  
Healthy Subjects ◽  
Reference Range ◽  
Mean Value ◽  
Normal Serum ◽  
Healthy People ◽  
Reference Ranges ◽  
Percentile Method ◽  
The Mean ◽  
Almost All

The purpose of this study is to determine the activity of serum adenosine deaminase (ADA) in healthy people, in connection with significant differences in published reference ranges from different authors. In our study, we examined 160 healthy subjects aged 18 to 84, of whom 64 were men and 96 women. We have determined serum adenosine deaminase levels using a method based on the ability of the enzyme adenosine deaminase to catalyze the deamination of adenosine to inosine and ammonia. The catalytic concentration is determined spectrophotometrically by the rate of reduction of NADH measured at 340 nm. We found that normal serum ADA values among our healthy subjects are higher than the recommended reference range for the method we use, namely below 18 U/l. Using the percentile method, we worked out the following reference ranges: for women 14.53 - 25.73 U/l and for men 18.46 – 27.50 U/l. For women, the mean value is 21.07 U/l, and for men 21.30 U/l. At 95% CI, the serum ADA values of almost all subjects included in the study are within the recommended and other authors range of 11.50 - 25.00 U/l.

scholarly journals A Comprehensive Review on Plant derived Natural products for Diabetes and its complication as nephropathya

2020 ◽  
Vol 10 (1-s) ◽  
pp. 111-113
Author(s):  
Wahid Ali ◽  
Wamique Khan ◽  
Wamique Khan ◽  
Neha Srivastava ◽  
Zoya Shakir ◽  
...  
Keyword(s):  
Coefficient Of Variation ◽  
Venous Blood ◽  
Intraclass Correlation ◽  
High Sensitivity ◽  
High Specificity ◽  
Appropriate Technology ◽  
Strong Positive Correlation ◽  
Linear Distribution ◽  
Reference Device ◽  
The Mean

The aim of this study was to evaluate the performance of the portable Hemoglobinometer “HbChek” by comparing its performance against automated Three-part hematology analyzer, Medonic M20. Total 731 venous blood samples were subjected through their total hemoglobin evaluation. Each sample was run only once on reference device and HbChek. The two set of values were comparatively analyzed. The repeatability of the performance of HbChek was also evaluated against Medonic M20 values. The scatter plot of HbChek values and Medonic M20 values showed linear distribution with regression correlations r=0.99. The intraclass correlation (ICC) between the two set of values was found to be 0.9952 with 95% confidence intervals (CI) ranging between 0.9945 and 0.9959. The mean difference in Bland–Altman plots of HbChek values against the Medonic M20 values was found to be -0.08 g/dL, with limits of agreement between 0.60 g/dL and -0.75 g/dL. Coefficient of Variation was found to be 2.8% (SD/Mean=0.35/12.4). Sensitivity & Specificity was found at 93.2 % & 98.6% respectively. These results suggest a strong positive correlation with laboratory machines differences less than 0.8 g/dL. In addition, high sensitivity &high specificity value with easiness of use can make HbChek appropriate technology for public health systems like Sub-Centers & PHCs. Keywords: Hemoglobinometer, Coefficient of Variation, Sensitivity & Specificity

scholarly journals A Multicenter Evaluation of an Activated Partial Thromboplastin Time Test, Cepho-Test

1977 ◽  
Author(s):  
D. Collen ◽  
H.C. Godal ◽  
P.M. Mannucci ◽  
I.M. Nilsson ◽  
C. Gilhuus-Moe ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Partial Thromboplastin Time ◽  
High Sensitivity ◽  
Mean Value ◽  
Activated Partial Thromboplastin Time ◽  
Satisfactory Precision ◽  
Time Test ◽  
The Mean ◽  
Aptt Reagent ◽  
Control Plasma

To compare the sensitivity and precision of the Activated Partial Thromboplastin Time (APTT) test Cephotest to that of APTT methods in current use, Cepho-test and current APTT method (Leuven and Milan: Locally modified Thrombofax/kaolin procedures; Malmoe: Automated APTT; Oslo: APTT of human brain/kaolin) were performed in parallel (20 tests) on lyophilized standard plasmas of 4 levels of factors VIII. The mean value (1 standard deviation) of Cephotest on Control Plasma Normal was 36.3 (2.21) s in Leuven, 31.7 (1.13) s in Oslo, 35.0 (1.36) s in Milan and 35.0 (1.16) s in Malmoe. The corresponding values of the local APTT methods were 50.2 (I.58) s, 34.5 (1.27) s, 51.9 (1.17) s and 38.8 (1.23) s, respectively. In Oslo, Milan and Malmoe, the sensitivity of Cephotest was superior to that of the local APTT reagent at all levels of factor VIII. In Leuven, the local APTT method had a higher ratio than Cephotest. There was no statistical significant differences between the standard deviation of Cephotest and the local APTT methods. The study indicates that Cephotest has a high sensitivity, satisfactory precision and is subjected to only minor interlaboratory variations.

Plasma protein-bound sialic acid in patients with colorectal polyps of known histology

1991 ◽  
Vol 37 (2) ◽  
pp. 200-204 ◽  
Author(s):  
Shahram Shahangian ◽  
Herbert A Fritsche ◽  
John I Hughes ◽  
Richard S Foemmel ◽  
Nonda Katopodis
Keyword(s):  
Colorectal Cancer ◽  
Sialic Acid ◽  
Cancer Patients ◽  
Healthy Subjects ◽  
Mean Value ◽  
Colorectal Polyps ◽  
Hyperplastic Polyps ◽  
The Mean ◽  
Colorectal Cancer Patients ◽  
Colorectal Adenocarcinomas

Abstract Protein-bound sialic acid (PBSA) was measured in serial plasma specimens from 62 healthy subjects, 48 patients with colorectal polyps, and 30 patients with colorectal adenocarcinomas. The mean plasma PBSA concentration in healthy smokers was significantly greater than that in healthy nonsmokers and healthy ex-smokers (P less than 0.0001). Villoglandular polyps were associated with higher plasma PBSA values than were the most benign hyperplastic polyps (P less than 0.025). Patients with the most neoplastic villoglandular and villous polyps had significantly greater (P less than 0.010-0.050) plasma PBSA values than healthy subjects. Polypectomy decreased the mean PBSA value significantly to the mean value for healthy subjects only for patients with villoglandular (P less than 0.010) or villous (P less than 0.050) polyps. Colorectal cancer patients had mean plasma PBSA concentrations significantly greater than those for the healthy subjects (P much less than 0.001) and the polyp patients (P much less than 0.001). Surgery significantly reduced (P less than 0.025) the mean PBSA value for the cancer patients to the mean PBSA value observed for the healthy subjects.

Behavior of Antithrombin III, Determined as Protein Concentration and Biologic Activity, in Subjects with Neoplastic Disease

1982 ◽  
Vol 68 (3) ◽  
pp. 205-209 ◽  
Author(s):  
Vittorio Pengo ◽  
Cosimo Guerra ◽  
Giuseppe Cartei ◽  
Mario Fiorentino
Keyword(s):  
Healthy Subjects ◽  
Protein Concentration ◽  
Antithrombin Iii ◽  
Mean Value ◽  
Neoplastic Disease ◽  
Biologic Activity ◽  
At Iii ◽  
Coagulation Proteins ◽  
The Mean

Antithrombin III (AT III), the primary inhibitor of plasma protease coagulation proteins, was evaluated in groups of patients with different neoplastic disease. When compared with that of 25 healthy subjects, the mean value of AT III biologic activity was elevated in all groups, significantly in gastrointestinal (p < 0.02) and lung (p < 0.001) tumors, lymphoma (p < 0.02) and in the group with various primary cancers (p < 0.05). No difference was found between 46 patients tested under chemoradiotherapy and 216 patients who had not undergone therapy for at least 1 month. Four patients with clinical thrombosis had normal AT III biologic activity. Of the 262 patients studied, 14 had low AT III biologic activity without clinical thrombosis and normal protein concentration. In 71 patients (27%) an excess of immunoassayable protein of 20% or more over biologic activity was found. Double immunoelectrophoresis performed in 5 of these showed for 3 patients an enlarged second arc of precipitation. Moreover, no correlation was observed between the activity and protein AT III concentration (r = 0.05). The likelihood of the presence of circulating AT III-protease complexes is discussed.

scholarly journals Sonographic Assessment of Heel Pad Thickness in Patients With Poorly Controlled Diabetes

2019 ◽  
Vol 35 (5) ◽  
pp. 374-379 ◽  
Author(s):  
Benjamin Effiong Udoh ◽  
Bassey Eyo Archibong ◽  
Akpama Egwu Egong
Keyword(s):  
Lipid Profile ◽  
Healthy Subjects ◽  
Biochemical Parameters ◽  
Hemoglobin A1c ◽  
Mean Value ◽  
Control Group ◽  
Diabetic Patients ◽  
Heel Pad ◽  
The Mean ◽  
Apparently Healthy

The aim was to compare the heel pad thickness (HPT) in diabetic patients with high biochemical parameters (fasting blood sugar [FBS], hemoglobin A1c [HbA1c], and lipid profile) with nondiabetic counterparts. A total of 438 subjects made up of 216 diabetics with high biochemical parameters (poorly controlled) and 222 apparently healthy subjects were recruited. The HPT, FBS level, HbA1c values and lipid profile, and duration of diabetes mellitus were assessed. Results showed that the mean HPT was 13.33 ± 1.29 mm in the control subjects and 16.79 ± 1.84 mm in diabetics. The HPT among diabetics differed significantly from the control group ( P < .05). The mean value of HbA1c in the control group was 5.4 ± 1.3 compared to diabetics with values of 8.53 ± 2.1. The values of HbA1c among diabetics were significantly higher than that of the control group ( P < .05). HPT had a significant linear relationship with HbA1c among the diabetic subjects ( r = 0.42, P < .05).

The Maximal Sniff in the Assessment of Diaphragm Function in Man

1985 ◽  
Vol 69 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Juliet M. Miller ◽  
John Moxham ◽  
Malcolm Green
Keyword(s):  
Clinical Practice ◽  
Coefficient Of Variation ◽  
Quantitative Method ◽  
Normal Subjects ◽  
Mean Value ◽  
Transdiaphragmatic Pressure ◽  
Diaphragm Function ◽  
The Mean ◽  
Lower Limits ◽  
Neuromuscular Impairment

1. We studied diaphragm function in a total of 64 normal subjects, who had no past or present respiratory or neuromuscular impairment. 2. We measured transdiaphragmatic pressure (Pdi) during maximal sniffs and compared these values with Pdi during maximal static inspiratory efforts (PImax.). 3. The range of Pdi during maximal sniffs (82-204 cm H2O) had better defined lower limits than Pdi during PImax. (16-164 cm H2O) and a higher mean value : mean + sd for maximal sniffs was 137 + 28 cm H2O and for PImax. was 90 + 37 cm H2O. 4. The reproducibility of sniff Pdi was assessed in eight randomly chosen subjects over 3 days: the mean coefficient of variation was 7.2%. By comparison the coefficient of variation of Pdi during PImax. was 13.0% in seven subjects. 5. The maximal sniff is a spontaneous manoeuvre, easily performed, repeatable without tiring, and reproducible. Its measurement provides a more reliable quantitative method for assessment of diaphragm strength, which has potential in clinical practice.

Platelet and adipocyte thermogenesis in hypothyroid patients: a microcalorimetric study

1985 ◽  
Vol 108 (3) ◽  
pp. 361-366 ◽  
Author(s):  
Stig Valdemarsson ◽  
Birger Fagher ◽  
Pavo Hedner ◽  
Mario Monti ◽  
Peter Nilsson-Ehle
Keyword(s):  
Thyroid Hormones ◽  
Heat Production ◽  
Healthy Subjects ◽  
Mean Value ◽  
Metabolic Effects ◽  
Adipocyte Size ◽  
Before And After ◽  
The Mean ◽  
Hypothyroid Patients ◽  
Adequate Method

Abstract. Direct microcalorimetry was used for measurements of heat production in cell suspensions of platelets and adipocytes, obtained from hypothyroid patients before and after 3 months on full l-thyroxine substitution. Platelet heat production was significantly lower than normal before treatment and increased in all 10 patients studied; the mean value increased from 51.3 ± 1.6 fW/cell before to 57.1 ± 1.8 fW/cell after therapy (P< 0.001). Similarily, adipocyte heat production was initially significantly lower than normal and increased during treatment in all 6 patients investigated. The mean value for heat production per adipocyte was 18.8 ± 1.7 pW/cell before and 32.4 ± 2.5 pW/cell after therapy (P < 0.025), which is still below the level recorded in lean healthy subjects. The adipocyte size did not change significantly. The increase in adipocyte heat production was correlated to the increase in S-triiodothyronine levels (r = 0.84, P <0.05). In hypothyroidism, the total metabolic activity seems to be comparatively more reduced in adipocytes than in platelets. A difference may exist between these cells with regard to recovery of normal metabolic acitivity during treatment for hypothyroidism. Direct microcalorimetry appears to be an adequate method for monitoring net metabolic effects of thyroid hormones in these cells.

scholarly journals Influence of Age, Posture and Intra-Individual Variation on Plasma Levels of Atrial Natriuretic Peptide

1989 ◽  
Vol 26 (6) ◽  
pp. 481-486 ◽  
Author(s):  
A C I T L Tan ◽  
P W C Kloppenborg ◽  
T J Benraad
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Individual Variation ◽  
Coefficient Of Variation ◽  
Healthy Subjects ◽  
Plasma Renin ◽  
Upright Position ◽  
Plasma Aldosterone ◽  
The Mean ◽  
Atrial Natriuretic

This paper describes some factors to which attention should be paid when atrial natriuretic peptide (ANP) values are to be interpreted. Changing from the supine to the sitting position decreased ANP levels, while no further decrease was observed when the upright position was assumed. On the other hand, plasma renin activity (PRA) increased only when changing from the sitting to the upright position. Returning to the supine position decreased PRA, while ANP did not change. Under these conditions plasma aldosterone levels did not differ in any of the four positions. No correlation was observed between the percentage changes of ANP, PRA and aldosterone. ANP values measured in 66 healthy subjects positively correlated with age ( r = 0·59, P < 0·01). To study intra-individual variation, ANP was sampled eight times within one hour. The mean, standard deviation and the coefficient of variation (CV) for each subject were calculated. The CV of 9 out of 15 subjects significantly exceeded the intra-assay coefficient of variation (7·0%), thereby indicating that ANP levels, like those of many other hormones, may exhibit endogenous fluctuations.

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