Micro-Scale Blood Lead Determinations in Screening: Evaluation of Factors Affecting Results

1975 ◽  
Vol 21 (4) ◽  
pp. 533-536 ◽  
Author(s):  
Martin Marcus ◽  
Melvin Hollander ◽  
Robert E Lucas ◽  
Norman C Pfeiffer
Keyword(s):  
Spatial Relationship ◽  
Glass Tube ◽  
Blood Lead ◽  
Accurate Method ◽  
Mean Value ◽  
Double Blind Study ◽  
Double Blind ◽  
Micro Scale ◽  
Scale Method ◽  
Macro Scale

Abstract The Delves micro-scale technique for blood lead analysis is an accurate method for screening capillary blood specimens, obtained by fingerstick, for lead intoxication. Results are affected by the age of cup, loop, and hollow-cathode tube and by the spatial relationship between optical tube and cup. Because the glass in many commercially available capillary tubes (used in specimen collection) contains lead and cannot be decontaminated, a lead-free glass tube must be used. A solution of citric acid in ethanol (20 g/liter) effectively cleanses the puncture site. A double-blind study of 207 specimens gave a mean value of 276.6 ± 105.8 µg/liter (1 SD) for the micro-scale method vs. 273.2 ± 99.0 for a macro-scale method. The mean coefficent of variation for the micro-scale method was 5.75% ± 1.9 (SD). We conclude that values of 480 µg/liter or below are not "toxic" (i.e., are significantly less than 600 µg/liter, the value at which therapy is begun). The method is shown to be satisfactory as a screening procedure and for confirming lead analyses done by other methods.

scholarly journals A multi-scale method for complex flows of non-Newtonian fluids

2021 ◽  
Vol 4 (6) ◽  
pp. 1-22
Author(s):  
Francesca Tedeschi ◽  
◽  
Giulio G. Giusteri ◽  
Leonid Yelash ◽  
Mária Lukáčová-Medvid'ová ◽  
...  
Keyword(s):  
Newtonian Fluids ◽  
Cauchy Stress ◽  
Complex Flows ◽  
Polymeric Fluids ◽  
Local Flow ◽  
Micro Scale ◽  
Multi Scale ◽  
Scale Method ◽  
Model Free ◽  
Macro Scale

<abstract><p>We introduce a new heterogeneous multi-scale method for the simulation of flows of non-Newtonian fluids in general geometries and present its application to paradigmatic two-dimensional flows of polymeric fluids. Our method combines micro-scale data from non-equilibrium molecular dynamics (NEMD) with macro-scale continuum equations to achieve a data-driven prediction of complex flows. At the continuum level, the method is model-free, since the Cauchy stress tensor is determined locally in space and time from NEMD data. The modelling effort is thus limited to the identification of suitable interaction potentials at the micro-scale. Compared to previous proposals, our approach takes into account the fact that the material response can depend strongly on the local flow type and we show that this is a necessary feature to correctly capture the macroscopic dynamics. In particular, we highlight the importance of extensional rheology in simulating generic flows of polymeric fluids.</p></abstract>

Evaluation of the Delves Micro System for Blood Lead Analysis

1973 ◽  
Vol 19 (3) ◽  
pp. 322-325 ◽  
Author(s):  
Jocelyn M Hicks ◽  
Aida N Gutierrez ◽  
Brenda E Worthy
Keyword(s):  
Atomic Absorption ◽  
Coefficient Of Variation ◽  
Blood Lead ◽  
Absorption Method ◽  
Pediatric Practice ◽  
Blood Samples ◽  
Micro Scale ◽  
Scale Method ◽  
Large Numbers ◽  
Finger Stick

Abstract Correlation between results of a conventional macroscale (5 ml of blood) atomic absorption procedure for lead determination and results of the Delves micro-scale (10 µl blood) atomic absorption method was high (0.96). Analyses of lead in capillary and intravenous blood samples also correlated well (0.93). The coefficient of variation of the Delves micro-scale method was 8% for a concentration of 46 µg of lead per milliliter. We conclude that the Delves microscale method—which is simpler, requires smaller samples than previous methods, and can be readily applied to capillary. ("finger-stick") blood—is very suitable for a pediatric practice and for the screening of large numbers of patients.

Effect of pomegranate fruit supplementation on performance and various markers in athletes and active subjects: a systematic review

2019 ◽  
pp. 1-15
Author(s):  
Alicja Urbaniak ◽  
Anna Skarpańska-Stejnborn
Keyword(s):  
Vessel Diameter ◽  
Whole Body ◽  
Double Blind Study ◽  
Double Blind ◽  
Physically Active ◽  
Highly Active ◽  
Body Strength ◽  
Rate Of Increase ◽  
Study Designs ◽  
Pomegranate Fruit

Abstract. The aim of the study was to review recent findings on the use of POM supplements in athletes of various disciplines and physically active participants. Eleven articles published between 2010 and 2018 were included, where the total number of investigated subjects was 176. Male participants constituted the majority of the group (n = 155), as compared to females (n = 21). 45% of research described was conducted on athletes, whereas the remaining studies were based on highly active participants. Randomised, crossover, double-blind study designs constituted the majority of the experimental designs used. POM supplementation varied in terms of form (pills/juice), dosage (50 ml–500 ml) and time of intervention (7 days–2 months) between studies. Among the reviewed articles, POM supplementation had an effect on the improvement of the following: whole body strength; feeling of vitality; acute and delayed muscle fatigue and soreness; increase in vessel diameter; blood flow and serum level of TAC; reduction in the rate of increase for HR, SBP, CK and LDH; support in the recovery of post-training CK, LDH, CRP and ASAT to their baseline levels; reduction of MMP2, MMP9, hsCRP and MDA; and increased activity of antioxidant enzymes (glutathione peroxidase and superoxide dismutase). In the majority of reviewed articles POM supplementation had a positive effect on a variety of parameters studied and the authors recommended it as a supplement for athletes and physically active bodies.

Metformin Decreases the High Plasminogen Activator Inhibition Capacity, Plasma Insulin and Triglyceride Levels in Non-Diabetic Obese Subjects

1987 ◽  
Vol 57 (03) ◽  
pp. 326-328 ◽  
Author(s):  
Ph Vague ◽  
I Juhan-Vague ◽  
M C Alessi ◽  
C Badier ◽  
J Valadier
Keyword(s):  
Plasminogen Activator ◽  
Fibrinolytic Activity ◽  
Plasma Insulin ◽  
Normal Glucose Tolerance ◽  
Double Blind Study ◽  
Obese Women ◽  
Double Blind ◽  
Normal Glucose ◽  
Plasma Insulin Levels ◽  
Obese Subjects

SummaryWe have previously observed a positive correlation between Plasminogen Activator Inhibition capacity (PA Inhibition), Body Mass Index (BMI) and plasma insulin levels in a population of non diabetic subjects. The anti diabetic biguanide Metformin which decreases insulin resistance has been reported to increase the blood fibrinolytic activity. Therefore we have studied the effect of Metformin on PA Inhibition levels in obese subjects with normal glucose tolerance. Eighteen obese women (O) (BMI: 31.4 ± 1.13, m ± S.E.M.) were compared to age matched controls (C) (BMI: 20.2 ± 0.8) and randomized to a 15 days treatment by Metformin (M) (1.7 g/day) or placebo (P) in a double blind study while on a weight maintaining diet. O compared to C had higher levels (m ± S.E.M.) of PA Inhibition (9 ± 1.8 IU/ml, versus 2.88 ± 0.29 p <0.01), lower euglobulin fibrinolytic activity (EFA) (4.95 ±1.17 mm versus 9 ± 0.29 p <0.05), higher plasma insulin (24.1 ±2.1. uU/ml), versus 12 ± 1 p <0.01) and triglyceride (1.32 ± 0.16 mmol/1, versus 0.8 ± 0.08 p <0.05). After 15 days of treatment, in group M a significant decrease in PA Inhibition (5.51 ± 1.4, versus 9.48 ±2.1 p <0.05) in plasma insulin (18.5 ±0.1, versus 24.5 ± 3.5, p <0.05) and plasma triglyceride (1.08 ± 0.1, versus 1.47 ± 0.3 p <0.05) and an increase in EFA (6.50 ± 0.28, versus 5.25 ± 0.35 p <0.05) were observed. No significant variation was observed in group P.

The Effect of Warfarin Sodium on the Duration of Platelet Aggregation

1967 ◽  
Vol 18 (03/04) ◽  
pp. 766-778 ◽  
Author(s):  
H. J Knieriem ◽  
A. B Chandler
Keyword(s):  
Platelet Count ◽  
Placebo Group ◽  
Platelet Aggregation ◽  
Prothrombin Time ◽  
Platelet Rich Plasma ◽  
Healthy Adults ◽  
Double Blind Study ◽  
Double Blind ◽  
Warfarin Sodium

SummaryThe effect of the administration of warfarin sodium (Coumadin®) on the duration of platelet aggregation in vitro was studied. Coumadin was given for 4 consecutive days to 10 healthy adults who were followed over a period of 9 days. The duration of adenosine diphosphate-induced platelet aggregation in platelet-rich plasma, the prothrombin time, and the platelet count of platelet-rich plasma were measured. Four other healthy adults received placebos and participated in a double-blind study with those receiving Coumadin.Although administration of Coumadin caused a prolongation of the prothrombin time to 2 or 21/2 times the normal value, a decrease in the duration of platelet aggregation was not observed. In most individuals who received Coumadin an increase in the duration of platelet aggregation occurred. The effect of Coumadin on platelet aggregation was not consistently related to the prothrombin time or to the platelet count. In the placebo group there was a distinct relation between the duration of platelet aggregation and the platelet count in platelet-rich plasma.The mean increase in the duration of platelet aggregation when compared to the control value before medication with Coumadin was 37.7%. In the placebo group there was a mean increase of 8.4%. The difference between the two groups is significant (p <0.001). Increased duration of platelet aggregation also occurred in two individuals who received Coumadin over a period of 10 and 16 days respectively.

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