Extraction of cyclic AMP for the determination in the competitive protein binding assay

The changes in free calcium, total calcium, albumin, protein, pH, lactate, sodium, magnesium, and potassium values during and following venous stasis (3 min at an external pressure of 100 mmHg) with and without forearm exercise have been measured. The pattern of changes observed with time were dependent on the presence or absence of forearm exercise. Without exercise significant changes are only observed at l min following stasis and then the increases are only moderate (free calcium 2.0%, total calcium 2.4%, albumin 6.9%, and protein 5.9%). However, when the forearm is exercised, larger increases (free calcium 8.6%, total calcium 8.4%, albumin and protein 12.4%) were observed for all parameters following stasis. These increases took 1 to 3 min to return to baseline for most parameters. Only potassium and magnesium went below baseline during the recovery period. It is recommended that when a tourniquet is used to aid in obtaining venous blood samples for these analytes, exercise of the forearm be avoided. If forearm exercise is unavoidable, then the sample should be obtained 1 to 3 min after release of the tourniquet.     

Use of total patient data for indirect estimation of reference intervals for 40 clinical chemical analytes in Turkey.

In the present study we used patient data to calculate laboratory-specific indirect reference intervals. These values were compared with reference intervals obtained for a healthy group according to recommendations of the International Federation of Clinical Chemistry and Laboratory Medicine and manufacturer suggestions. Laboratory results (422,919 records) from all subjects of 18-45 years of age over a 1-year period were retrieved from our laboratory information system and indirect reference intervals for 40 common analytes were estimated using a modified Bhattacharya procedure. Indirect reference intervals for most of the biochemical analytes were comparable, with small differences in lower [alkaline phosphatase (ALP) (male), alanine aminotransferase (ALT), creatine kinase, iron (male), total iron-binding capacity, folic acid, calcium (female), lactate dehydrogenase (LDH), lipoprotein (a) [Lp(a)], thyroid-stimulating hormone (TSH), total triiodothyronine (T(3)), direct bilirubin, apolipoprotein A-I (apoA-I), glucose, homocysteine, total cholesterol, ferritin, total protein, ceruloplasmin, sodium, blood urea nitrogen (BUN) and uric acid (female)] and/or upper limits [albumin, ALP (male), amylase, apoA-I, creatine kinase-MB (CK-MB), total iron-binding capacity, phosphorus, glucose, total cholesterol, gamma-glutamyltransferase (gamma-GT), magnesium, total protein, high-density lipoprotein cholesterol (HDL-C), total T(3), ALP (male), ALT, aspartate aminotransferase (AST) (male), direct bilirubin (male), creatine kinase, iron, folic acid (female), Lp(a), uric acid and triglycerides], to the reference intervals determined for healthy subjects in our laboratory. The indirect reference intervals, with the exception of a few parameters (creatinine, direct total bilirubin, calcium, BUN and potassium), were not similar to the reference intervals suggested by the manufacturers. We conclude that laboratory-specific reference intervals can be determined from stored data with a relatively easy and inexpensive method. Indirect reference intervals derived from stored data may be particularly suitable for the evaluation of results for the presenting population.     

Non-homogeneous separation of triglycerides, gamma-glutamyltransferase, C-reactive protein and lactate dehydrogenase after centrifugation of lithium-heparin tubes

BACKGROUND: Clinical chemistry testing is influenced by a variety of preanalytical variables, including sample preparation. The presence of a diluted plasma layer at the top of primary tubes containing plasma citrate has recently been reported. However, no indication is available so far on the potential non-homogeneous distribution of clinical chemistry analytes during centrifugation of primary tubes containing lithium-heparin as an additive. METHODS: A total of 40 lithium-heparin plasma samples were collected from volunteers and immediately centrifuged. An aliquot was obtained from the upper 0.4 mL of plasma (upper aliquot), 1.0 mL of plasma was discarded, and a second aliquot (lower aliquot) was obtained from the remaining plasma. The concentrations of alanine aminotransferase, albumin, alkaline phosphatase, amylase, amylase pancreatic, aspartate aminotransferase, direct bilirubin, total bilirubin, blood urea nitrogen, calcium, chloride, cholesterol, C-reactive protein (CRP), creatinine, creatine kinase, gamma-glutamyltransferase (GGT), glucose, high-density lipoprotein-cholesterol, iron, lactate dehydrogenase (LDH), magnesium, phosphate, potassium, total protein, sodium, triglycerides and uric acid were assayed on a Roche/Hitachi Modular System P according to the manufacturer's specifications and using proprietary reagents. Sodium, chloride and potassium were measured on a Roche/Hitachi Modular System using indirect ion-selective electrode methods. RESULTS: We observed a statistically significant difference between the upper and lower aliquots for CRP (3.88+/-0.67 vs. 3.94+/-0.68 mg/L; p=0.025), GGT (32.1+/-8.0 vs. 31.8+/-8.0 U/L; p=0.013), LDH (395+/-19 vs. 386+/-20 U/L; p=0.010) and triglycerides (1.29+/-0.09 vs. 1.27+/-0.09 mmol/L; p=0.001); results for the other analytes were not significantly different. In no case did the mean percentage bias recorded between aliquots exceed the current analytical quality specifications for desirable bias. CONCLUSIONS: The results of our investigation show that plasma layer stratification might occur in primary lithium-heparin tubes for a limited number of routine clinical chemistry tests, introducing a statistically significant bias in the measurement of GGT, LDH, triglycerides and CRP in the upper vs. the bottom section. When delayed testing is necessary for these parameters, we suggest that plasma should be separated after centrifugation and appropriately mixed before delayed/repeated analysis or aliquoting.     

The impact of pre-analytical variations on biochemical analytes stability: A systematic review

ObjectiveA common problem in clinical laboratories is maintaining the stability of analytes during pre‐analytical processes. The aim of this study was to systematically summarize the results of a set of studies about the biochemical analytes stability.MethodsA literature search was performed on the Advanced search field of PubMed using the keywords: “(stability) AND (analytes OR laboratory analytes OR laboratory tests OR biochemical analytes OR biochemical tests OR biochemical laboratory tests).” A total of 56 entries were obtained. After applying the selection criteria, 20 articles were included in the study.ResultsIn the 20 included references, up to 123 different analytes were assessed. The 34 analytes in order of the most frequently studied analytes were evaluated: Alanine aminotransferase, aspartate aminotransferase, potassium, triglyceride, alkaline phosphatase, creatinine, total cholesterol, albumin, lactate dehydrogenase, sodium, calcium, γ‐glutamyltransferase, total bilirubin, urea, creatine kinase, inorganic phosphate, total protein, uric acid, amylase, chloride, high‐density lipoprotein, magnesium, glucose, C‐reactive protein, bicarbonate, ferritin, iron, lipase, transferrin, cobalamin, cortisol, folate, free thyroxine, and thyroid‐stimulating hormone. Stable test results could be varied between 2 hours and 1 week according to the type of samples and/or type of blood collection tubes on a basic classification set as refrigerated or room temperature.ConclusionsBiochemical analytes stability could be improved if the best pre‐analytical approaches are used.     

Haemolysis as an interference factor in clinical chemistry

Using fully mechanized analytical equipment, interference by haemolysis in the determination of 26 clinical chemical parameters was determined quantitatively by adding haemolysate to serum. Haemoglobin concentrations up to 6.6 g/l caused essentially no interference in the following determinations: albumin (immuno-nephelometric), alpha-amylase, calcium, chloride, cholesterol, cholinesterase, creatinine, iron, glucose, glutamate dehydrogenase, uric acid, urea, sodium, inorganic phosphate, total protein, transferrin and triglycerides. In the presence of haemoglobin, erroneously high values were found for: lactate dehydrogenase (haemoglobin higher than 0.2 g/l), aspartate aminotransferase, potassium and acid phosphate (haemoglobin higher than 1.5 g/l), creatine kinase (haemoglobin higher than 2.5 g/l) and alanine aminotransferase (haemoglobin higher than 3.4 g/l). Erroneously low values were found for bilirubin (haemoglobin higher than 0.8 g/l), alkaline phosphatase and albumin (by electrophoresis) (haemoglobin higher than 1.5 g/l) and gamma-glutamyltransferase (haemoglobin higher than 3.0 g/l).     

Establishing pediatric reference intervals for 13 biochemical analytes derived from normal subjects in a pediatric endocrinology clinic in Korea

ObjectivesDefining pediatric reference intervals is one of the most difficult tasks for laboratory physicians. The continuously changing physiology of growing children makes their laboratory values moving targets. In addition, ethnic and behavioral differences might also cause variations. The aim of this study was to establish age- and sex-specific partitioned reference intervals for 13 serum biochemical analytes in Korean children.Design and methodsA total of 2474 patients, girls aged 2–14 years and boys aged 2–16 years, who underwent a short stature workup but were diagnosed as normal at the Pediatric Endocrinology Clinic of Severance Hospital (Seoul, Korea) between September 2010 and June 2012 were included in this study. The levels of serum calcium, inorganic phosphorus, blood urea nitrogen, creatinine, uric acid, glucose, total cholesterol, total protein, albumin, alkaline phosphatase, aspartic aminotransferase, alanine aminotransferase, and total bilirubin were measured using a Hitachi 7600 analyzer (Hitachi High-Technologies Corporation, Tokyo, Japan). Reference intervals were partitioned according to sex or age subgroups using the Harris and Boyd method.ResultsMost analytes except calcium and albumin required partitioning either by sex or age. Age-specific partitioned reference intervals for alkaline phosphatase, creatinine, and total bilirubin were established for both males and females after being partitioned by sex. Additional age-specific partitioning of aspartic aminotransferase in females and total protein and uric acid in males was also required. Inorganic phosphorus, total cholesterol, alanine aminotransferase, blood urea nitrogen, and glucose were partitioned only by sex.ConclusionsThis study provided updated age- and sex-specific pediatric reference intervals for 13 basic serum chemistry analytes from a sufficient number of healthy children by using a modern analytical chemistry platform.     

Influence of hemolysis on clinical chemistry parameters determined with Beckman Coulter tests – detection of clinically significant interference

The aim of this study was to examine the influence of hemolysis on 25 clinical chemistry parameters and to compare the resulting bias with clinically significant differences and the manufacturer’s specifications. Using freeze-thawing of the treated blood aliquot of each subject (N?=?17), four hemolysis levels were prepared with hemolysis index (HI) and hemoglobin concentration as follows: (+)=0.5–0.99?g/L, (2+)=1–1.99?g/L, (3+)=2–2.99?g/L and (4+)=3–4.99?g/L. All analytes were tested on the Beckman Coulter AU480 analyzer using proprietary reagents. It was considered that the interference was detected if the 95% confidence interval for mean differences (%) between hemolyzed and non-hemolyzed samples did not include zero. Clinically significant interference was judged against reference change value (RCV). Hemolysis interference was detected for: alpha-amylase, alkaline phosphatase (ALP), aspartate aminotransferase (AST), total and conjugated bilirubin, creatine kinase (CK), CK-MB, ?-glutamyltransferase (GGT), iron, lactate dehydrogenase (LD), magnesium, potassium, total protein and uric acid at HI=(1+); alanine aminotransferase (ALT) and phosphate at HI=(2+); urea at HI=(3+); albumin and cholinesterase at HI=(4+). Even at the greatest hemolysis degree, HI=(4+), no interference was detected for calcium, chloride, creatinine, C-reactive protein (CRP), glucose and sodium. Clinically significant difference was exceeded for LD at HI=(1+); CK-MB at HI=(2+); AST and potassium at HI=(3+); total bilirubin at HI=(4+). The presented results did not support the manufacturer’s claim for CK and GGT. Establishing HI thresholds for reporting or suppressing test results is the responsibility of each laboratory, taking into account the manufacturer’s data, but also its own investigations.     

The effect of sex, deviation from ideal weight and sampling time on blood constituents in presumably healthy subjects.

In order to verify the influence of sampling time on blood constituents, populations of supposedly healthy subjects were grouped according to age, sex, deviation from their ideal weight, state of fasting or nonfasting, and time of sampling. Each fasting subject in one group underwent two samplings during the course of a morning: the first at 08.00 and the second between 09.00 and 12.00. In the second group, the first was taken at 13.00, and the second between 14.00 and 16.00. Subjects in the second group had eaten a standard meal of 700 calories at 12.00. Differences between the paired samples from a given individual are discussed with respect to the time of sampling for plasma urea, creatinine, proteins, albumin, calcium, sodium, potassium, cholesterol, uric acid, chloride ions, phosphate, bilirubin, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine phosphokinase, alkaline phosphatase, hemoglobin and erythrocyte and leukocyte counts. Variations due to the time of sampling were large for phosphorus, bilirubin, and leukocyte count.     

Intra-individual variation of analytes in serum from patients with chronic liver diseases

The average biological intra-individual CV in 20 patients with chronic liver diseases (CLD), estimated for 14 analytes during a stationary phase, significantly exceeded that for a normal group in the cases of Na+, K+, Cl-, total protein, albumin, cholinesterase, hemoglobin, and alpha-amylase; it did not differ significantly from the normal group for cholesterol, alkaline phosphatase, aspartate aminotransferase, and alanine aminopeptidase; and it was significantly lower than in the normal group for alanine aminotransferase and gamma-glutamyltransferase. There were no significant sex-related differences in mean intra-individual variation in CLD patients. Individual values were gaussian-distributed for all analytes, including enzymes. The estimated biological component of intra-individual variation and the analytical variation as determined for each laboratory can be used to derive decision-making criteria in monitoring CLD.     

Influence of the needle bore size used for collecting venous blood samples on routine clinical chemistry testing.

BACKGROUND: Despite remarkable advances in technology and laboratory automation, results of laboratory testing still suffer from a high degree of preanalytical variability. Although there is no definitive evidence, the use of small-gauge needles for venipuncture is usually discouraged to reduce the chance of producing unsuitable specimens. METHODS: The purpose of this investigation was to assess the influence of the needle size used to collect venous blood on the measurement of 14 common analytes, including free hemoglobin, the most representative enzymes, protein-bound substances and electrolytes. Results for venous blood samples collected from 20 fasting voluntary physicians using either a 23- (0.60 mmx19 mm) or 25-gauge-needle (0.50 mmx19 mm) butterfly devices with polyvinyl chloride tubing (1.40 mmx300 mm) were compared with reference specimens collected using a 21-gauge-needle (0.80 mmx19 mm) butterfly device with polyvinyl chloride tubing (1.40 mmx300 mm). RESULTS: All means for paired samples collected using the smaller needles did not differ significantly from the reference specimen by paired Student's t-test analysis. Passing-Bablok regression analysis and Pearson's or Spearman (creatine kinase, aspartate aminotransferase, alanine aminotransferase and chloride) correlation were acceptable for most of the analyses, although a lower correlation coefficient was observed for electrolytes. In addition, when expressed as a percentage of the mean for paired samples, the s(y,x) value exceeded the desirable bias for free hemoglobin, glucose, lactate dehydrogenase, aspartate aminotransferase, sodium, chloride, calcium and magnesium (in samples collected using both 23 G and 25 G needles) and potassium (in samples collected using a 25 G needle). Although Bland-Altman plot analysis and +/-1.96 SD agreement intervals for the set of differences between values was acceptable overall, the bias was rather broad for free hemoglobin and several critical electrolytes (calcium, chloride, potassium, sodium), exceeding the respective limits for desirable bias. CONCLUSIONS: The results of our investigation indicate that 23 G needles, if handled correctly, will not introduce any statistically or clinically significant error to the measurement results compared to a 21 G needle. For the 25 G needle, we observed increased variability for potassium compared to a 23 G needle. Small-bore needles of 25 G or less cannot be universally recommended when collecting venous blood for clinical chemistry testing and should be reserved for selected circumstances, such as in patients with problematical venous accesses and newborns. In such cases, however, the bias introduced by the use of smaller needles should always be taken into consideration when interpreting test results.     

注射用灯盏花素对临床生化检验项目的干扰研究

目的研究注射用灯盏花素对常用临床生化检验项目检测结果的干扰。方法将注射用灯盏花素加入体检健康者混合血清标本中作为实验标本,以注射用水加入体检健康者混合血清标本中作为对照标本,采用日立公司7600-010全自动生化分析仪及配套试剂进行总胆红素(TBIL)、直接胆红素(DBIL)、总蛋白(TP)、清蛋白(ALB)、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)、尿素(UREA)、肌酐(CREA)、尿酸(UA)、总胆固醇(TCHO)、三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、a-羟丁酸脱氢酶(α-HBDH)、肌酸激酶(CK)、肌酸激酶同工酶MB(CKMB)、钾(K)、钠(Na)、氯(CL)、钙(Ca)检测,并进行统计学分析。结果注射用灯盏花素对CREA、UA、TG、TCHO、HDL-C及LDL-C检测存在干扰可能。结论注射用灯盏花素可干扰部分生化检验项目的检测。对于可能存在药物干扰的检验项目,应在用药前或药物经半衰期代谢后进行检测。     

Gross errors made by routine blood sampling from two sites using a tourniquet applied at different positions.

Tourniquet application in routine blood sampling procedures may induce considerable haemoconcentration and thereby augment the concentration of serum protein and protein-bound substances. To evaluate this effect serum protein, calcium and magnesium were measured in 31 healthy persons before and after 3-min venous stasis induced by a standardized tourniquet. Four sites of tourniquet and two sampling sites on the arm were compared. The concentration of measured serum constituents rose after the stasis period (5--13% rise in serum protein), the changes being similar at all tourniquet positions. However, blood sampled from a cubital arm vein showed significantly larger haemoconcentration than samples obtained simultaneously more distally on the arm. Taking three samples in a series, the serum concentration of protein, calcium and magnesium rose from tube to tube (5--10% change). The study demonstrates that neither use of a standardized tourniquet nor release of the tourniquet before blood sampling eliminates the errors inherent in routine venepuncture. Adjustment to a constant serum protein level minimizes these errors.     

19项临床生化检验项目的分析前变异和个体内生物学变异

目的 调查19项临床生化项目的分析前变异和个体内生物学变异.方法 募集21名健康成年志愿者,自每名志愿者连续抽取10份血样,用于分析前变异试验,抽血和样品处理考虑左右臂、止血带使用、采血管品牌和类型、离心前后贮存等因素;再自每名志愿者抽取另外3份血样,每份间隔1周,按规定进行样品处理,用于生物学变异试验;用常规方法检测各样品的19项生化项目,利用方差分析原理计算分析前变异和个体内生物学变异.结果 由各种分析前处理造成的系统变异总体小于样品随机变异,样品随机变异是分析前变异的主要分量;Cl、Na、Ca分析前变异较小(GV值＜1%),其他检验项目CV值为1%～7%不等;不同检验项目生物学变异不同,平均生物学变异Cl、Na、Ca较小(CV值＜2%),TB、TG、ALT、CK较大(CV值＞20%),其余检验项目介于两者之间,与国外数据库数据接近;个体内生物学变异存在较大个体差异.结论 本研究得出19项常见生化检验项目在我国实验室情况下的分析前变异和基于国人的个体内生物学变异,研究结果可望在检验结果临床应用和临床检验质量控制中发挥作用.     

Influence of hemolysis on routine clinical chemistry testing.

BACKGROUND: Preanalytical factors are the main source of variation in clinical chemistry testing and among the major determinants of preanalytical variability, sample hemolysis can exert a strong influence on result reliability. Hemolytic samples are a rather common and unfavorable occurrence in laboratory practice, as they are often considered unsuitable for routine testing due to biological and analytical interference. However, definitive indications on the analytical and clinical management of hemolyzed specimens are currently lacking. Therefore, the present investigation evaluated the influence of in vitro blood cell lysis on routine clinical chemistry testing. METHODS: Nine aliquots, prepared by serial dilutions of homologous hemolyzed samples collected from 12 different subjects and containing a final concentration of serum hemoglobin ranging from 0 to 20.6 g/L, were tested for the most common clinical chemistry analytes. Lysis was achieved by subjecting whole blood to an overnight freeze-thaw cycle. RESULTS: Hemolysis interference appeared to be approximately linearly dependent on the final concentration of blood-cell lysate in the specimen. This generated a consistent trend towards overestimation of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, creatine kinase (CK), iron, lactate dehydrogenase (LDH), lipase, magnesium, phosphorus, potassium and urea, whereas mean values of albumin, alkaline phosphatase (ALP), chloride, gamma-glutamyltransferase (GGT), glucose and sodium were substantially decreased. Clinically meaningful variations of AST, chloride, LDH, potassium and sodium were observed in specimens displaying mild or almost undetectable hemolysis by visual inspection (serum hemoglobin < 0.6 g/L). The rather heterogeneous and unpredictable response to hemolysis observed for several parameters prevented the adoption of reliable statistic corrective measures for results on the basis of the degree of hemolysis. CONCLUSION: If hemolysis and blood cell lysis result from an in vitro cause, we suggest that the most convenient corrective solution might be quantification of free hemoglobin, alerting the clinicians and sample recollection.     

Endotoxin alters serum-free choline and phospholipid-bound choline concentrations, and choline administration attenuates endotoxin-induced organ injury in dogs

This study in dogs was performed to assess circulating choline status during endotoxemia and to determine whether choline administration can protect dogs from endotoxin-induced tissue injuries. Baseline serum-free and phospholipid-bound choline concentrations were 19.2 +/- 0.6 micromol/L and 3700 +/- 70 micromol/L, respectively. After intravenous endotoxin infusion, serum-free choline concentrations decreased by 14% to 49% (P < 0.05-0.001) at 2 to 6 h after 0.02 mg/kg endotoxin, and increased by 23% to 98% (P < 0.05-0.001) at 1 to 48 h after 1 mg/kg endotoxin. Serum phospholipid-bound choline concentrations increased by 19% to 27% (P < 0.05) at 12 to 24 h or by 18% to 53% (P < 0.05-0.001) at 1 to 48 h after 0.02 or 1 mg/kg endotoxin, respectively. The changes in serum-free and -bound choline levels in response to endotoxin were accompanied by dose- and time-related elevations in serum cortisol and biochemical markers for tissue injury and/or organ dysfunction. Intravenous administration of choline (20 mg/kg) 5 min before, and 4 and 8 h after endotoxin (1 mg/kg) attenuated endotoxin-induced elevations in serum alanine aminotransferase (P < 0.05-0.001), aspartate aminotransferase (P < 0.05-0.001), gamma-glutamyl transferase (P < 0.05-0.001), alkaline phosphatase (P < 0.05-0.001), lactate dehydrogenase (P < 0.05-0.001), myocardial creatine kinase (P < 0.001), urea (P < 0.05-0.01), creatinine (P < 0.05), uric acid (P < 0.01-0.001), and tissue necrosis factor-alpha (P < 0.001). Choline also attenuated alanine aminotransferase (P < 0.05-0.01), alkaline phosphatase (P < 0.05-0.01), lactate dehydrogenase (P < 0.05-0.01), creatine kinase (P < 0.05-0.001), myocardial creatine kinase (P < 0.05-0.001), and uric acid (P < 0.05-0.01), but failed to alter the serum urea, creatinine, aspartate aminotransferase, and gamma-glutamyl transferase responses to 0.02 mg/kg endotoxin. These data show that choline status is altered during endotoxemia and that choline administration diminishes endotoxin-induced tissue injury.     

Does haemoconcentration account for the changes in serum enzyme activities following haemodialysis?

We have estimated serum lactate dehydrogenase and isoenzymes, alkaline phosphatase, aspartate aminotransferase, amylase, creatine kinase, urea, creatinine and albumin on 29 patients with end-stage renal failure, before and after regular maintenance haemodialysis. All enzymes except serum aspartate aminotransferase, creatine kinase and LDH₁ were significantly increased (0.01 >P > 0.001 or P < 0.001) following dialysis. Because of the significant changes in serum albumin (P < 0.001) following dialysis, correction was made to all post-dialysis enzyme activities for the degree of haemoconcentration. When corrected no changes occurred in any of these enzyme activities following haemodialysis. We have also confirmed that in vitro dialysis of a predialysis serum does not alter the LDH isoenzyme activities, when corrections are made for changes in albumin concentration.     

Treatment with atorvastatin reduces serum adipocyte-fatty acid binding protein value in patients with hyperlipidaemia

BACKGROUND: Adipocyte-fatty acid binding protein (A-FABP) is a circulating protein expressed in adipocytes and macrophages. Several recent studies demonstrated that A-FABP might be involved in the pathogenesis of metabolic syndrome, particularly in dyslipidaemia, insulin resistance and atherosclerosis. The aim of this study was to investigate the influence of atorvastatin treatment (20 mg day(-1) for 3 months) on serum A-FABP value in subjects with hyperlipidaemia. MATERIALS AND METHODS: Anthropometric and serum analyses were performed for body mass index, A-FABP, triglycerides, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, uric acid, alanine aminotransferase (ALT), aspartate aminotransferase (AST), high sensitive C-reactive protein (hs-CRP), creatine kinase (CK) and glucose on 26 subjects (BMI 30.3 +/- 6.0, mean age 62 +/- 10 years) with hyperlipidaemia who met the criteria: total cholesterol > 5.2 mmol L(-1), LDL cholesterol > 3.3 mmol L(-1) and triglycerides < 3 mmol L(-1). RESULTS: After the 3-month therapy, a significant reduction in total cholesterol (P < 0.001), LDL cholesterol (P < 0.001), glucose (P < 0.001), A-FABP (from 44.6 +/- 26.2 to 38.6 +/- 19.3 g L(-1), P < 0.01), uric acid (P < 0.05), AST (P < 0.05) and triglycerides (P < 0.05) values was observed. No difference was found in BMI, CK, ALT, hs-CRP, or HDL cholesterol values. A significant difference in the serum A-FABP value before and after the therapy remains after the correction for total cholesterol value (P < 0.001). A positive correlation between serum A-FABP and glucose was found (P < 0.05). CONCLUSIONS: In conclusion, our study confirmed in vivo that atorvastatin reduces serum A-FABP by a pleiotropic mechanism and supports the hypothesis that A-FABP is involved in atherosclerotic actions.     

The effect of long-distance running on some biochemical variables.

Biochemical variables have been measured in a group of volunteers during and after a long-distance run. Plasma glucose levels remained relatively constant and a significant decrease in plasma bicarbonate was noted. Plasma sodium, chloride, total protein, albumin and calcium showed significant increased of an order compatible with water losses occurring during the run. Plasma potassium, urea, creatinine, uric acid, phosphate and bilirubin all show much more marked and variable increases. The plasma enzymes alkaline phosphatase, lactate dehydrogenase, aspartate aminotransferase and creatine kinase likewise increased significantly throughout the run. Whilst most constituents showed a tendency to return to normal at 20-30 hours after the run, gross increases were observed for aspartate aminotransferase and creatine kinase.     

Microchemical analysis for 13 constituents of plasma from healthy children.

Normal values for 13 chemical constituents of plasma were estimated from results for 837 presumably healthy children. Ninety microliters of specimen was analyzed for lactate dehydrogenase, aspartate aminotransferase, alkaline phosphatase, inorganic phosphorus, total calcium, total cholesterol, total proteins, albumin, uric acid, urea nitrogen, alanine aminotransferase, total bilirubin, and glucose. We used two Abbott ABA-100 Bichromatic Analyzers interfaced directly to the ABA Data Management System. For each test age- and sex-related variations were assessed and normal values were estimated for six different age groups.     

The effect of a short burst of exercise on activity values of enzymes in sera of healthy young men

We report the effect of exercise on the activity values of five enzymes in sera as studied in four healthy male volunteers. The underlying purpose of this present study was to produce an increase in the activity values in the sera of selected enzymes found in muscle. Then by observing the decay rate of these enzymes, we computed the inter-individual differences in clearance rates (serum half-life) of these enzymes.Blood specimens were collected just prior to exercise, 1 h after exercise, and on eight additional times up to 93 h after exercise. All specimens were assayed on one occasion for activity values of creatine kinase, asparate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase. We found increases in the three muscle enzymes with average increases being: creatine kinase, +116%; aspartate aminotransferase, +41%; and lactate dehydrogenase, +32%; all of which remained above baseline values for 53 h or longer. In the case of creatine kinase, a monoexponential decay curve depicted the data (from the 19-h specimen to the 67-h specimen). The calculated “apparent serum half-life” for creatine kinase varied from 38 h to 118 h in the subjects tested.