Clinical Chemistry Reference Values Research Articles

The metabolic pattern could be used for early detection of stable ischemic heart disease and hypertensive heart disease

Introduction Cardiovascular diseases are a leading cause of morbidity and mortality worldwide accounting for 32% of all deaths across EU countries. Ischemic heart disease (IHD), known also as coronary artery disease (CAD) comprised 17% of all deaths. For up to 20% of patients, the first manifestation of IHD is sudden cardiac arrest occurring outside the hospital. Estonia stands out with the much higher prevalence of the cardiovascular diseases than Western-European countries. In Estonia, half of deaths are caused by circulatory system diseases according to the Estonian Causes of Death Registry. An urgent necessity for more sensitive biomarkers identifying altered health conditions specifically among the variety of patients with different risk factors is foreseeable. Metabolomics of human biofluids has turned into a rapidly developing area and as a quantitative molecular level method may offer extra advantages in clarification of the pathogenesis and therapy monitoring. Methods We profiled the metabolic pattern of serum of patients classified according to International Classification of Diseases (ICD10). Most of the patients were treated with statins, ACE-inhibitors (ACEI) or angiotensin receptor blockers (ARB) and acetylsalicylic acid as an anticholesterol, an antihypertensive, and an anticoagulant medication. The control group was selected from healthy volunteers without known heart and vascular diseases and without medication. This study was performed in accordance with the Helsinki Declaration and was approved by the Tallinn Medical Research Ethics Committee. The filtered venous serum from age and gender matched IHD patients ICD10 coded I20 (n = 12), I25.2 (n = 6), I11 (n = 25) and control individuals (n = 20) were analyzed using one-dimensional proton nuclear magnetic resonance (1H NMR) spectroscopy. These spectra were used for metabolic profiling and concentration calibration (Chenomx Inc) followed by statistical analysis using one-way Anova and principal component analysis (PCA). Results The study evaluates serum of 43 individuals of Estonian origin. We identified from serum spectra about 83 metabolites. The metabolite concentrations are in good accordance with results provided by clinical chemistry reference values, the Human Metabolome Database (HMDB) library and various studies. The IHD patients are characterized by the increased concentration of acetylacetate, choline, pyruvate, betaine, formate and by the decreased concentration of alanine, creatine, glycine, histidine, lactate, proline, urea and other biomolecules. The major implications found in the serum of IHD patients are related to energy metabolism. A number of calibrated metabolites are related to human microbiome according to the information provided in the literature: trimethylamine-N-oxide (TMAO), formate and hippuric acid. Interestingly, the altered health conditions might be potentially characterized by altered microbiome. Chemometrics analysis showed a significant distinction between the patients and control individuals. The metabolic profile of ischemic patients with or without previous myocardial infarction appears to be similar. The pattern of HHD patients follows the changes of the serum of IHD patients in regard of some amino acids concentrations but is negatively correlated in regard to formate and 3-hydroxybutyrate. Conclusion PCA of 1H NMR detected serum metabolites exhibit a significant difference among the IHD patients, HHD patients and control individuals. These data demonstrate that metabolomics approach may be useful for the early detection of some circulatory diseases, for detection of synergistic pathways involved in the development of altered health conditions, and molecular understanding of particular health condition. This relatively inexpensive, non-invasive and reproducible approach may be useful for the molecular understanding and early prevention of health conditions, improvement of surveillance and therapy. This work was supported by the Estonian Research Council grant PUT 1534.

Hematological and biochemical reference values for C57BL/6, Swiss Webster and BALB/c mice

O uso de animais na pesquisa científica tem contribuído significativamente para o desenvolvimento da ciência, promovendo vários avanços na compreensão da maquinaria metabólica, bem como a descoberta de tratamentos e medidas preventivas aplicadas à medicina humana e veterinária. O desenvolvimento e utilização de métodos alternativos é encorajado, no entanto, em algumas situações, ainda é necessária a utilização de animais em conformidade com termos éticos. Estabelecer valores de referência hematológicos e bioquímicos para animais de laboratório é essencial para avaliar alterações funcionais, no entanto, existem poucos dados na literatura sobre estes valores, sendo fundamentalmente uma base comparativa. O presente trabalho foi delineado para estabelecer valores de referência hematológicos e bioquímicos em linhagens camundongos utilizados em pesquisa científica. Foram avaliados o perfil sanguíneo (hemograma, reticulócitos e mielograma) e a determinação bioquímica sérica de proteínas totais, albumina, glicose, colesterol, triglicerídeos, cálcio e fósforo. Foram utilizados camundongos C57BL/6, BALB/c e Swiss Webster, do sexo masculino, 2-3 meses de idade. Os resultados padronizam intervalos de referência em camundongos criados em Biotério, refletindo a condição esperada nesses animais submetidos à investigação científica.

Clinical Chemistry Reference Intervals in a Rwandan Population

Aim: To establish clinical chemistry reference intervals for the Rwandan population. Study Design: A population-based cross-sectional study. Place and Duration of Study: The study was carried out in three blood transfusion centres: Buhanda, Ruhango and Nyaruteja, between August and December 2011. Methods: Serum clinical chemistry tests were performed on a Cobas C311 automated chemistry analyzer. Results: Results of 187 subjects (age range: 17-54 years) presented as median, with 2.5th-97.5th percentiles (95% reference interval) in brackets are as follows: For males: alanine aminotransferase: 25 (12-43) U/L; aspartate aminotransferase: 29 (16-47) U/L; gamma-glutamyl transferase: 22 (9-77) U/L; total bilirubin: 0.6 (0.2-1.7) mg/dL; direct bilirubin: 0.2 (0.1-0.4) mg/dL; creatinine: 0.8 (0.5-1.1) mg/dL; uric acid: 5 (3-7) mg/dL. For males and females: alkaline phosphatase: 71 (27-122) U/L; amylase: 144 (50-235) U/L; lactate dehydrogenase: 176 (114-237) U/L; triglycerides: 82 (32-172) mg/dL; highdensity lipoprotein: 48 (29-86) mg/dL; glucose: 87 (70-114) mg/dL; total protein: 7.6 (6.5- 8.5) g/dL; albumin: 4.4 (3.4-5.4) g/dL; sodium: 142 (137-147) mmol/L; potassium: 4.1 (3.3-5.0) mmol/L; chloride: 106 (100-112) mmol/L; phosphate: 1.16 (0.87-1.49) mmol/L. Conclusion: The clinical chemistry reference values are in agreement with those reported in other African studies, with variations.

Serum chemistry reference values in free‐ranging North Atlantic male walruses (Odobenus rosmarus rosmarus) from the Svalbard archipelago

Information regarding health and disease is limited for walruses, a keystone species in arctic marine ecosystems. Serum chemistry analysis is a useful clinical tool for the health assessment of walruses, but only a few captive Pacific walruses have been evaluated. The aim of this study was to determine serum chemistry reference values for free-ranging male Atlantic walruses (Odobenus rosmarus rosmarus) on Svalbard and to assess potential differences in animals with low and high tissue levels of organic pollutants. Blood samples were collected from 17 wild, adult, male Atlantic walruses chemically immobilized with etorphine at eastern Svalbard (Norway). Serum was obtained for routine biochemical analysis as well as nonesterified free fatty acids (NEFA) and cortisol tests. Serum protein concentration was also measured by agarose gel electrophoresis. Reference values (ranges) included alanine aminotransferase (12-51 U/L), aspartate aminotransferase (54-137 U/L), alkaline phosphatase (42-243 U/L), creatine kinase (32-506 U/L), lactate dehydrogenase (480-1322 U/L), amylase (0-23 U/L), lipase (68-298 U/L), total protein (68-91 g/L), albumin (25.3-34.8 g/L), creatinine (84-137 mumol/L), urea (8.2-19.9 mmol/L), bilirubin (0-4 mumol/L), cholesterol (4.4-7.3 mmol/L), NEFA (0.1-0.4 mmol/L), triglycerides (0.6-2.2 mmol/L), calcium (2.0-2.7 mmol/L), phosphorus (1.7-2.8 mmol/L), sodium (147-162 mmol/L), potassium (4.7-7.4 mmol/L), chloride (102-115 mmol/L), and cortisol (<28-214 nmol/L). Walruses exposed to high levels of organic pollutants (n=6) had significantly lower (P=.022) phosphorus concentration than those with low levels of pollutants (n=6). The clinical chemistry reference values determined in this study can serve as baseline data for future health-related studies of walruses in a changing Arctic and may also be helpful for health evaluations of walruses in captivity. Impacts of the exposure of marine mammals to organic pollutants should be further investigated.

Drug Metabolizing Enzymes and Transporters mRNA in Peripheral Blood Mononuclear Cells of Healthy Subjects: Biological Variations and Importance of Preanalytical Steps

Quantification in peripheral blood mononuclear cells of mRNA of drug metabolizing enzymes or drug targets could give interesting, new information in the field of pharmacogenomics and molecular mechanisms. However, for the interpretation of these data, it is necessary to know mRNA biological variations. In this review, we propose a strategy based on the production and interpretation of clinical chemistry reference values. We discuss the concept of reference values; the necessity to master pre-analytical variations of CYP and ABC transporters; the choice of the analytical methods and of the reference genes; and finally the biological variations themselves. In particular, we focus on the importance of considering homogeneity for age, sex, degree of adiposity, tobacco and alcohol intake, food habits, and drug consumption, including their inductive effects, at the phase of subject recruitment. All this information is useful to define the partition and exclusion factors to obtain mRNA reference limits.

Estimating clinical chemistry reference values based on an existing data set of unselected animals

In an attempt to standardise the determination of biological reference values, the International Federation of Clinical Chemistry (IFCC) has published a series of recommendations on developing reference intervals. The IFCC recommends the use of an a priori sampling of at least 120 healthy individuals. However, such a high number of samples and laboratory analysis is expensive, time-consuming and not always feasible, especially in veterinary medicine. In this paper, an alternative (a posteriori) method is described and is used to determine reference intervals for biochemical parameters of farm animals using an existing laboratory data set. The method used was based on the detection and removal of outliers to obtain a large sample of animals likely to be healthy from the existing data set. This allowed the estimation of reliable reference intervals for biochemical parameters in Sarda dairy sheep. This method may also be useful for the determination of reference intervals for different species, ages and gender.

Clinical chemistry reference values for 75-year-old apparently healthy persons

Clinical chemistry reference values for elderly persons are sparse and mostly intermixed with those for younger subjects. To understand the links between metabolism and aging, it is paramount to differentiate between "normal" physiological processes in apparently healthy elderly subjects and metabolic changes due to long-lasting diseases. The Vienna Transdanube Aging (VITA) study, which began in 2000 and is continuing, will allow us to do just that, because more than 600 male and female volunteers aged exactly 75 years (to exclude any influence of the "aging" factor in this cohort) are participating in this study. Extensive clinical, neurological, biochemical, psychological, genetic, and radiological analyses, with a special emphasis on consumption of medication and abuse of drugs, were performed on each of the probands. The multitude of data and questionnaires obtained made possible an a posteriori approach to select individuals fulfilling criteria for a reference sample group of apparently healthy 75-year-old subjects for our study. Specific analytes were quantified on automated clinical analyzers, while manual methods were used for hormonal analytes. All clinical chemistry analytes were evaluated using in-depth statistical analyses with SPSS for Windows. In all, reference intervals for 45 analytes could be established. These include routine parameters for the assessment of organ functions, as well as hormone concentrations and hematological appraisals. Because all patients were reevaluated after exactly 30 months in the course of this study, we had the opportunity to reassess their health status at the age of 77.5 years. This was very useful for validation of the first round data set. Data of the second round evaluation corroborate the reference limits of the baseline analysis and further confirm our inclusion and exclusion criteria. In summary, we have established a reliable set of reference data for hormonal, hematological, and clinical chemistry analytes for elderly subjects. These values will be very useful for our future attempts to correlate disease states and aging processes with metabolic factors.

Establishing canine clinical chemistry reference values for the Hitachi � 912 using the International Federation of Clinical Chemistry (IFCC) recommendations

The aim of this study was to establish population-based canine clinical chemistry reference values for the Hitachi 912 (Roche Diagnostics GmbH, Germany) with regard to age, sex, breed, housing and intended use. Reference biochemistry values for 22 variables are presented from 308 clinical healthy dogs, 145 females and 163 males, approximately 1 month to 13 years of age and of various breeds. For each variable the data were examined for homogeneity and, when suspected, outliers were excluded using the range test. Non-parametric analysis was used to calculate the conventional central 95% interval. Then the two-sided non-parametric 0.9 confidence interval of each percentile was determined. Finally, the effects of subgrouping were examined using the Kruskal–Wallis test and p <0.05 was considered significant. Significant age influences were found for 20 of the 22 variables, 14 showing clinical relevance. Significant breed effects could be found for 10 of the 22 parameters, including clinically relevant lower total protein concentrations for retrievers, lower lipase activity for sled dogs, lower total bilirubin concentrations for terriers and higher total bilirubin for Molossians. Differences between male and female were present for six of the 22 variables but had no clinical relevance. Housing and intended use influenced some of the values, but these differences were of no clinical significance. We successfully established canine clinical chemistry reference values for the Hitachi 912. The IFCC Recommendations on Reference Values offered a good framework for establishing standardised reference values, and make it possible for several laboratories to share the same values. Our results clearly indicate that subgrouping according to age and breed is necessary to obtain accurate reference values.

Hematologic and Clinical Chemistry Reference Values in Red Lories (Eos spp.)

We established reference ranges for three hematologic and 15 clinical chemistry parameters of 40 clinically healthy birds of the genus Eos. The following species were included to the study: Eos histrio (n = 19), Eos squamata (n = 8), Eos bomea (n = 5), Eos reticulata (n = 4), Eos cyanogenia (n = 4). Detailed information concerning methodology, which is often missing in papers dealing with reference values, is included. As far as possible, data are compared with literature, and some thoughts on obvious deviations are given. The problem of establishing reference values in rare species is reviewed.

Blood plasma chemistries from wild mourning doves held in captivity.

Despite the extensive amount of research conducted on mourning doves (Zenaida macroura), no biochemical reference values exist for this species. Our objective, therefore, was to establish base line clinical chemistry reference values for mourning doves to assist with establishing clinical diagnoses. Wild mourning doves were captured 19 March 1996 to 8 August 1996, and 6 February 1998 to 12 May 1998; blood samples were collected from 382 mourning doves. Plasma biochemical values were established for glucose, sodium, potassium, chloride, enzymatic CO2, albumin, total protein, globulin, calcium, phosphorus, cholesterol, magnesium, aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH), and uric acid. These reference values are invaluable for determining diagnosis of diseases of the gastrointestinal, hepatic, renal, cardiovascular, musculoskeletal, and endocrine systems.

Clinical chemistry reference values of foals during the first year of life.

Clinical chemistry reference values of foals during the first year of life.