scholarly journals Within-day biological variation and hour-to-hour reference change values for hematological parameters

2017 ◽  
Vol 55 (7) ◽  
Author(s):  
Judith M. Hilderink ◽  
Lieke J.J. Klinkenberg ◽  
Kristin M. Aakre ◽  
Norbert C.J. de Wit ◽  
Yvonne M.C. Henskens ◽  
...  
Keyword(s):  
Hematological Parameters ◽  
Biological Variation ◽  
Natural Fluctuation ◽  
Sample Collection ◽  
Blood Samples ◽  
Variation Data ◽  
Random Fluctuations ◽  
Analytical Variation ◽  
Variability Data

AbstractBackground:Middle- and long-term biological variation data for hematological parameters have been reported in the literature. Within-day 24-h variability profiles for hematological parameters are currently lacking. However, comprehensive hour-to-hour variability data are critical to detect diurnal cyclical rhythms, and to take into account the ‘time of sample collection’ as a possible determinant of natural fluctuation. In this study, we assessed 24-h variation profiles for 20 hematological parameters.Methods:Blood samples were collected under standardized conditions from 24 subjects every hour for 24 h. At each measurement, 20 hematological parameters were determined in duplicate. Analytical variation (CVResults:All parameters showed higher CVConclusions:We present complete 24-h variability profiles for 20 hematological parameters. Hour-to-hour reference changes values may help to better discriminate between random fluctuations and true changes in parameters with rhythmic diurnal oscillations.

scholarly journals The EuBIVAS Project: Within- and Between-Subject Biological Variation Data for Serum Creatinine Using Enzymatic and Alkaline Picrate Methods and Implications for Monitoring

2017 ◽  
Vol 63 (9) ◽  
pp. 1527-1536 ◽  
Author(s):  
Anna Carobene ◽  
Irene Marino ◽  
Abdurrahman Coşkun ◽  
Mustafa Serteser ◽  
Ibrahim Unsal ◽  
...  
Keyword(s):  
Serum Creatinine ◽  
Clinical Chemistry ◽  
Biological Variation ◽  
European Federation ◽  
Healthy Individuals ◽  
Homogeneity Analysis ◽  
Variation Data ◽  
Performance Specifications ◽  
Age Range ◽  
Analytical Variation

Abstract BACKGROUND The European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) European Biological Variation Study (EuBIVAS) has been established to deliver rigorously determined biological variation (BV) indices. EuBIVAS determined BV for serum creatinine using the enzymatic and alkaline picrate measurement methods. METHOD In total, 91 healthy individuals (38 males, 53 females; age range, 21–69 years) were bled for 10 consecutive weeks at 6 European laboratories. An equivalent protocol was followed at each center. Sera were stored at −80 °C before analysis. Analyses for each patient were performed in duplicate within a single run on an ADVIA 2400 system (San Raffaele Hospital, Milan). The data were subjected to outlier and homogeneity analysis before performing CV-ANOVA to determine BV and analytical variation (CVA) estimates with confidence intervals (CI). RESULTS The within-subject BV estimates [CVI (95% CI)] were similar for enzymatic [4.4% (4.2–4.7)] and alkaline picrate [4.7% (4.4–4.9)] methods and lower than the estimate presently available online (CVI = 5.9%). No significant male/female BV differences were found. Significant differences were observed in mean creatinine values between men and women and between Turkish individuals and those of other nationalities. Between-subject BV (CVG) estimates, stratified accordingly, produced CVG values similar to historical BV data. CVA was 1.1% for the enzymatic and 4.4% for alkaline picrate methods, indicating that alkaline picrate methods fail to fulfill analytical performance specifications for imprecision (CVAPS). CONCLUSIONS The serum creatinine CVI obtained by EuBIVAS specifies a more stringent CVAPS than previously identified. The alkaline picrate method failed to meet this CVAPS, raising questions regarding its future use.

First data on the biological variation and quality specifications for plasma ammonia concentrations in healthy subjects

2016 ◽  
Vol 54 (5) ◽  
Author(s):  
Fatma Ucar ◽  
Gonul Erden ◽  
Seyda Ozdemir ◽  
Nurgul Ozcan ◽  
Erdem Bulut ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Plasma Sample ◽  
Biological Variation ◽  
Test Results ◽  
Healthy Individuals ◽  
Variation Data ◽  
Quality Specifications ◽  
Collection Period ◽  
First Time ◽  
Analytical Variation

AbstractBackground:Most of the factors causing preanalytical and analytical variation in ammonia measurement have been identified. Biological variation data for ammonia is still lacking. We therefore estimated the components of biological variation (within-subject=CVMethods:Blood samples from 20 healthy subjects were collected in K2EDTA tubes daily over a period of 4 consecutive days from each subject. Each plasma sample was split into two aliquots; one was immediately analyzed as the samples were collected and the other was stored –80 °C until testing at the end of the collection period and analyzed at once in one analytical run. All samples were analyzed in duplicate. Estimations were calculated according to Fraser and Harris methods.Results:CVConclusions:The present study for the first time described the components of biological variation for ammonia in healthy individuals. These data regarding biological variation of ammonia could be useful for a better evaluation of ammonia test results in clinical interpretation and for determining quality specifications based on biological variation.

Long-term stability of glucose: 96-h study using Terumo Glycaemia tubes

2016 ◽  
Vol 54 (3) ◽  
Author(s):  
Theresa Winter ◽  
Anne Greiser ◽  
Matthias Nauck ◽  
Astrid Petersmann
Keyword(s):  
Glucose Concentration ◽  
Room Temperature ◽  
Venous Blood ◽  
Sample Collection ◽  
Multicenter Studies ◽  
Entire Study ◽  
Blood Samples ◽  
Term Stability ◽  
Long Term Stability

AbstractLong transportation times of samples can occur due to centralization of laboratories, and also in, for instance epidemiological multicenter studies with one core laboratory. Unsatisfactory glycolysis inhibition is known to threaten the correct measurements of glucose concentration in patient samples. In former studies Terumo Glycaemia tubes proved to be superior to other anticoagulant systems for time periods of up to 24 h. We investigated long-term stability of glucose concentration in Terumo Glycaemia tubes for up to 96 h at room temperature and imitated transport conditions by continuous sample shaking.Human venous blood samples were collected from 40 healthy blood donors using Terumo Glycaemia tubes. Immediately after sampling, tubes were mixed according to the manufactures recommendations. To simulate transportation conditions samples were placed on a shaker for the entire study period and maintained at room temperature. Samples were (re)centrifuged at 0, 24, 36, 48, 72 and 96 h prior to measuring glucose concentration. The glucose concentration at 0 h was used as baseline for evaluation of long-term stability.The recovery of glucose was 100% throughout the study, including the 96-h measurements. Deviations of single glucose measurements were within the imprecision of the measurement procedure.Terumo Glycaemia tubes can effectively stabilize glucose in whole blood samples kept at room temperature on a shaker during a 96-h time period. Therefore, we consider Terumo Glycaemia tubes as a suitable glucose stabilizing tube for long intervals between sample collection and glucose quantification.

scholarly journals Importance of Preanalytical Factors in Measuring Cr and Co Levels in Human Whole Blood: Contamination Control, Proper Sample Collection and Long-Term Storage Stability

2020 ◽  
Author(s):  
Yuliya L Sommer ◽  
Cynthia D Ward ◽  
Joaudimir Castro Georgi ◽  
Po-Yung Cheng ◽  
Robert L Jones
Keyword(s):  
Stainless Steel ◽  
Whole Blood ◽  
Consumer Products ◽  
Blood Collection ◽  
Sample Collection ◽  
Blood Samples ◽  
Contamination Control ◽  
Human Whole Blood

Abstract A number of errors with potentially significant consequences may be introduced at various points in the analytical process, which result in skewed, erroneous analytical results. Precautionary procedures such as contamination control, following established sample collection protocols, and having a complete understanding of the long-term stability of the elements of interest can minimize or eliminate these errors. Contamination control is critical in the quantification of Cr and Co in human whole blood. Cr and Co levels in most biological samples are low, but these elements occur naturally in the environment and are often found in commercial and consumer products, which increases the risk of contamination. In this paper, we demonstrated that lot screening process in which we pre-screen a sub-set of manufactured lots used in collecting, analyzing and storing blood samples is a critical step in controlling Cr and Co contamination. Stainless steel needles are often utilized in blood collection but are considered as a potential source of introducing metal contamination to the patient sample. We conducted two studies to determine if there is a possibility of Cr or Co leaching into the human whole blood from the needles during blood collection. We analyzed blood collected from 100 donors and blood collected in vitro in the laboratory from designated vessel containing spiked blood with higher levels of Cr and Co. Two blood tubes were consecutively collected through one needle. In both studies, Cr and Co concentration levels in the two consecutively collected tubes were compared. Based on the results from donor and in vitro blood collection studies, we concluded that there was no Cr and Co leaching from the limited sets of stainless steel needles used in these studies. Furthermore, we demonstrated that Cr and Co human whole blood samples are stable for 1 year stored at temperatures of −70, −20 and 4°C and 6 months at room temperature.

scholarly journals Critical appraisal and meta-analysis of biological variation studies on glycosylated albumin, glucose and HbA1c

2020 ◽  
Vol 1 (3) ◽  
Author(s):  
Carmen Ricós ◽  
Pilar Fernández-Calle ◽  
Elisabet Gonzalez-Lao ◽  
Margarida Simón ◽  
Jorge Díaz-Garzón ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Critical Appraisal ◽  
Meta Analysis ◽  
Biological Variation ◽  
Evidence Based ◽  
Literature Searches ◽  
Variation Data ◽  
Global Estimates ◽  
Systematic Literature Searches

AbstractObjectivesNumerous biological variation (BV) studies have been performed over the years, but the quality of these studies vary. The objectives of this study were to perform a systematic review and critical appraisal of BV studies on glycosylated albumin and to deliver updated BV estimates for glucose and HbA1c, including recently published high-quality studies such as the European Biological Variation study (EuBIVAS).MethodsSystematic literature searches were performed to identify BV studies. Nine publications not included in a previous review were identified; four for glycosylated albumin, three for glucose, and three for HbA1c. Relevant studies were appraised by the Biological Variation Data Critical Appraisal Checklist (BIVAC). Global BV estimates were derived by meta-analysis of BIVAC-compliant studies in healthy subjects with similar study design.ResultsOne study received BIVAC grade A, 2B, and 6C. In most cases, the C-grade was associated with deficiencies in statistical analysis. BV estimates for glycosylated albumin were: CVI=1.4% (1.2–2.1) and CVG=5.7% (4.7–10.6), whereas estimates for HbA1c, CVI=1.2% (0.3–2.5), CVG=5.4% (3.3–7.3), and glucose, CVI=5.0% (4.1–12.0), CVG=8.1% (2.7–10.8) did not differ from previously published global estimates.ConclusionsThe critical appraisal and rating of BV studies according to their methodological quality, followed by a meta-analysis, generate robust, and reliable BV estimates. This study delivers updated and evidence-based BV estimates for glycosylated albumin, glucose and HbA1c.

scholarly journals Effect of Chronic Administration of 5-(3-chlorophenyl)-4-Hexyl-2,4 -Dihydro-3H-1,2,4-Triazole-3-Thione (TP-315)—A New Anticonvulsant Drug Candidate—On Living Organisms

2021 ◽  
Vol 22 (7) ◽  
pp. 3358
Author(s):  
Anna Makuch-Kocka ◽  
Marta Andres-Mach ◽  
Mirosław Zagaja ◽  
Anna Śmiech ◽  
Magdalena Pizoń ◽  
...  
Keyword(s):  
Hematological Parameters ◽  
Anticonvulsant Drug ◽  
Living Organism ◽  
Drug Candidate ◽  
In Vitro Tests ◽  
Maximal Electroshock ◽  
Tp 315 ◽  
The Impact ◽  
Chronic Use

About 70 million people suffer from epilepsy—a chronic neurodegenerative disease. In most cases, the cause of the disease is unknown, but epilepsy can also develop as the result of a stroke, trauma to the brain, or the use of psychotropic substances. The treatment of epilepsy is mainly based on the administration of anticonvulsants, which the patient must most often use throughout their life. Despite significant progress in research on antiepileptic drugs, about 30% of patients still have drug-resistant epilepsy, which is insensitive to pharmacotherapy used so far. In our recent studies, we have shown that 4-alkyl-5-aryl-1,2,4-triazole-3-thiones act on the voltage-gated sodium channels and exhibit anticonvulsant activity in an MES (maximal electroshock-induced seizure) and 6Hz test in mice. Previous studies have shown their beneficial toxic and pharmacological profile, but their effect on a living organism during chronic use is still unknown. In the presented study, on the basis of the previously conducted tests and the PAMPA (parallel artificial membrane permeability assay) BBB (blood–brain barrier) test, we selected one 1,2,4-triazole-3-thione derivative—TP-315—for further studies aimed at assessing the impact of its chronic use on a living organism. After long-term administration of TP-315 to Albino Swiss mice, its effect on the functional parameters of internal organs was assessed by performing biochemical, morphological, and histopathological examinations. It was also determined whether the tested compound inhibits selected isoforms of the CYP450 enzyme system. On the basis of the conducted tests, it was found that TP-315 does not show nephrotoxic nor hepatotoxic effects and does not cause changes in hematological parameters. In vitro tests showed that TP-315 did not inhibit CYP2B6, CYP2D6, CYP3A4, or CYP3A5 enzymes at the concentration found in the serum of mice subjected to long-term exposure to this compound.

scholarly journals Biological variation and reference change value data for serum copper, zinc and selenium in Turkish adult population

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ceylan Bal ◽  
Serpil Erdogan ◽  
Gamze Gök ◽  
Cemil Nural ◽  
Betül Özbek ◽  
...  
Keyword(s):  
Adult Population ◽  
Reference Intervals ◽  
Serum Copper ◽  
Biological Variation ◽  
Serum Samples ◽  
Reference Change Value ◽  
Index Of Individuality ◽  
Copper Zinc ◽  
Clinically Significant ◽  
Analytical Variation

Abstract Objectives Calculation of biological variation (BV) components is very important in evaluating whether a test result is clinically significant. The aim of this study is to analyze BV components for copper, zinc and selenium in a cohort of healthy Turkish participants. Methods A total of 10 serum samples were collected from each of the 15 healthy individuals (nine female, six male), once a week, during 10 weeks. Copper, zinc and selenium levels were analyzed by atomic absorption spectrometer. BV parameters were calculated with the approach suggested by Fraser. Results Analytical variation (CVA), within-subject BV (CVI), between-subject BV (CVG) values were 8.4, 7.1 and 4.3 for copper; 4.2, 9.1 and 13.7 for zinc; 7.6, 2.5 and 6.9 for selenium, respectively. Reference change values (RCV) were 30.46, 27.56 and 22.16% for copper, zinc and selenium, respectively. The index of individuality (II) values were 1.65, 0.66 and 0.36 for copper, zinc and selenium, respectively. Conclusions According to the results of this study, traditional reference intervals can be used for copper but we do not recommend using it for zinc and selenium. We think that it would be more accurate to use RCV value for zinc and selenium in terms of following significant changes in recurrent results of a patient.

scholarly journals Factors Enhancing Serum Syndecan-1 Concentrations: A Large-Scale Comprehensive Medical Examination

2019 ◽  
Vol 8 (9) ◽  
pp. 1320
Author(s):  
Kazumasa Oda ◽  
Hideshi Okada ◽  
Akio Suzuki ◽  
Hiroyuki Tomita ◽  
Ryo Kobayashi ◽  
...  
Keyword(s):  
Large Scale ◽  
Prospective Observational Study ◽  
Nitrogen Concentration ◽  
Laboratory Data ◽  
University Hospital ◽  
Endothelial Glycocalyx ◽  
Sample Collection ◽  
Blood Samples ◽  
Triglyceride Concentration ◽  
Medical Examinations

Endothelial disorders are related to various diseases. An initial endothelial injury is characterized by endothelial glycocalyx injury. We aimed to evaluate endothelial glycocalyx injury by measuring serum syndecan-1 concentrations in patients during comprehensive medical examinations. A single-center, prospective, observational study was conducted at Asahi University Hospital. The participants enrolled in this study were 1313 patients who underwent comprehensive medical examinations at Asahi University Hospital from January 2018 to June 2018. One patient undergoing hemodialysis was excluded from the study. At enrollment, blood samples were obtained, and study personnel collected demographic and clinical data. No treatments or exposures were conducted except for standard medical examinations and blood sample collection. Laboratory data were obtained by the collection of blood samples at the time of study enrolment. According to nonlinear regression, the concentrations of serum syndecan-1 were significantly related to age (p = 0.016), aspartic aminotransferase concentration (AST, p = 0.020), blood urea nitrogen concentration (BUN, p = 0.013), triglyceride concentration (p < 0.001), and hematocrit (p = 0.006). These relationships were independent associations. Endothelial glycocalyx injury, which is reflected by serum syndecan-1 concentrations, is related to age, hematocrit, AST concentration, BUN concentration, and triglyceride concentration.

LRF and TRF test during long-term danazol treatment: increase of the LH and FSH responses but decrease of the prolactin and TSH responses

1983 ◽  
Vol 104 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. Leppäluoto ◽  
L. Rönnberg ◽  
P. Ylöstalo
Keyword(s):  
Clinical Symptoms ◽  
Follicular Phase ◽  
Blood Samples ◽  
Hormone Levels ◽  
Coefficients Of Variation ◽  
The Mean ◽  
Thyroid Hormone Levels ◽  
Low Serum

Abstract. Seven patients suffering from severe endometriosis were treated with danazol 200 mg × 3 daily for 6 months. Clinical symptoms were alleviated and menses disappeared in response to the treatment. After cessation of the treatment the menstrual bleedings returned in 1–3 months. Blood samples for determination of gonadotrophins, prolactin (Prl), oestradiol (E2), progesterone, thyroid hormones and thyrotrophin in radioimmunoassays were taken and a combined TRF and LRF test carried out in the follicular phase before treatment, at the 6th month of treatment and after reappearance of the first menses. There were no statistically significant changes in the basal levels of serum FSH, LH or TSH during the danazol treatment. Neither was there any change in episodic secretions of FSH, LH or Prl, as determined by the mean coefficients of variation of the hormone levels in seven consecutive samples taken at 20 min intervals. On the other hand, serum E2, Prl and thyroid hormone levels were significantly decreased in the 6th month of treatment. In the TRF-LRF test the responses of serum FSH and LH were significantly higher and those of serum Prl and TSH significantly lower during danazol treatment than before. Prl responses remained lowered after the treatment. It appears that low serum oestrogen levels, induced by the danazol treatment, sensitize the pituitary gonadotrophs to exogenous LRF, but make the sensitivity of thyrotrophs and lactotrophs lower to exogenous TRF. These results thus indicate that danazol does not make the pituitary gonadotrophs insensitive to LRF, but danazol may rather inhibit the secretion of hypothalamic LRF.

Sign in / Sign up

Export Citation Format

Share Document