In vitro activation of human leukocytes in response to contact with synthetic hernia meshes

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

N. Bryan, H. Ahswin, N.J. Smart, Y. Bayon, J.A. Hunt

Objectives Evaluation of an in vitro chemiluminescent screen to predict leukocyte ROS in response to surgical materials. Design and methods 6 surgical meshes; manufacture and knitting variations of polypropylene (PP), polyester terephtalate (PET) and polyglycolic acid (PGA) trialled healthy human blood (n=5). Materials and blood were incubated with pholasin. Pholasin emits photons in the presence of reactive oxygen species; secreted by activated leukocytes. Results Multifilament-PGA mesh stimulated the greatest ROS response from blood derived human leukocytes. Multifilament-PET light weight and multifilament-PP meshes stimulated similar levels of ROS production which were greater than monofilament-PP light, monofilament-PP and monofilament-PET light meshes. Data demonstrated statistical variations in trans-donor response to the materials. Conclusions An in vitro chemiluminescent assay can be used to assess leukocyte respiratory burst response to biomaterials. PGA mesh elicited the greatest ROS response. PP and PET monofilament meshes induce less ROS than multifilament equivalents. In vitro results correlate with previously published clinical responses to these materials.

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Posted on 27 May 2012 | 1:15 am

Association of follicle-stimulating hormone and sex hormone binding globulin with the metabolic syndrome in postmenopausal women

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Anna Stefanska, Grazyna Sypniewska, Irena Ponikowska, Malgorzata Cwiklinska-Jurkowska

Objectives We compared the association of follicle-stimulating hormone (FSH) and sex hormone binding globulin (SHBG) with metabolic syndrome (MetS). Design and methods We examined 320 postmenopausal women (148 with MetS and 172 without MetS). Results FSH was more strongly associated with MetS probability in the logistic regression model compared to SHBG. Receiver operating characteristic (ROC) curves comparison showed greater areas under the curve for FSH than SHBG concentrations. Conclusions FSH exhibited a stronger coherence to MetS than SHBG in postmenopausal women.

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Posted on 27 May 2012 | 1:15 am

Investigation of hypercalcemia

Publication year: 2012
Source:Clinical Biochemistry

David B. Endres

Hypercalcemia is a relatively common clinical finding. Primary hyperparathyroidism, hypercalcemia associated with malignancy and chronic renal failure (with calcium and vitamin D metabolite treatment or tertiary hyperparathyroidism) are the most common causes. Less common causes of hypercalcemia include vitamin D-related (granulomatous diseases, lymphoma, vitamin D intoxication), other endocrine (thyrotoxicosis), medications (milk-alkali, thiazides, lithium) and other causes (immobilization, familial hypocalciuric hypercalcemia). The clinical laboratory is central to the diagnosis and differential diagnosis of hypercalcemia. Its role has expanded from measuring routine chemistry tests such as total calcium, phosphate, creatinine and alkaline phosphate to include quantification of ionized calcium, parathyroid hormone (PTH) and vitamin D metabolites. In spite of this progress, the diagnosis and differential diagnosis of hypercalcemia can be significantly improved by: 1) increasing the availability and utilization of ionized calcium since total and corrected calcium are often inaccurate; 2) establishing more accurate reference intervals for parathyroid hormone by excluding individuals who are vitamin D insufficient or deficient; and 3) harmonizing intact PTH immunoassays.

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Posted on 27 May 2012 | 1:15 am

Laboratory detection of macro-aspartate aminotransferase: Case report and evaluation of the PEG-precipitation method

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Lisbeth Patteet, Marc Simoens, Marian Piqueur, Annick Wauters

Background Chronic elevated AST without other signs of liver disease, cardiac or skeletal abnormalities, is suggestive for macro-AST. Laboratory detection can be performed by gel filtration chromatography, ultrafiltration or precipitation with polyethylene glycol (PEG). Patient and methods A healthy 27year-old female was referred because of chronic elevated AST (116–704U/L) without other abnormalities. Macro-AST positivity was suspected since AST was no longer measurable in the supernatant of a serum sample (<3U/L) after PEG precipitation. Optimization of this method included analysis of proteins and lipids precipitated, testing the effect of different PEG concentrations and centrifugation times. 25% (m/v) PEG solution gave the most reliable results. No significant difference was seen between 10 and 30min centrifugation time. A reference range was obtained by analysis of 31 normal patient samples (mean % PEG precipitation activity 35.1% with 95% confidence limits of 14.5–62.5%). Retrospective analysis of 1371 patient samples with elevated AST revealed one other positive patient sample. Conclusion Early recognition of macro-AST, proven by simple PEG precipitation, can avoid time-consuming and invasive investigations.

Posted on 27 May 2012 | 1:15 am

False positive drugs of abuse immunoassays

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Bhushan M. Kapur

Posted on 27 May 2012 | 1:15 am

Development of multiplex real-time quantitative PCR for simultaneous detection of Chlamydia trachomatis and Ureaplasma parvum

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Hong-bo Wei, She-xiao Zou, Xiao-lin Yang, Dai-qin Yang, Xiang-dong Chen

Objectives Chlamydia trachomatis and Ureaplasma urealyticum are common pathogens of sexually transmitted diseases. The majority of human ureaplasma isolates belong to the new species U. parvum. Clinically, C. trachomatis and U. parvum usually double infect in the nongonococcal urethritis patients. A novel method for simultaneous detection of C. trachomatis and U. parvum was set up in the present work. Design and methods Multiple real-time quantitative PCR was developed to allow for rapid, sensitive, specific and quantitative detection of C. trachomatis and U. parvum, simultaneously. To evaluate the applicability of the multiplex real-time quantitative PCR assay to clinical specimens, 64 samples of cervical swabs collected were studied. Results Compared to the results obtained from single real-time quantitative PCR of C. trachomatis and U. parvum, the specificity, sensitivity and quantitative detection results of multiple real-time quantitative PCR are approximately identical with those of the former. Conclusions This assay will be of great value in the simultaneous and rapid diagnosis of C. trachomatis and U. parvum in the future.

Highlights

Posted on 27 May 2012 | 1:15 am

Soluble TNF? receptor type I and hepcidin as determinants of development of anemia in the long-term follow-up of heart failure patients

Publication year: 2012
Source:Clinical Biochemistry

A. Martínez-Ruiz, P.L. Tornel-Osorio, J. Sánchez-Más, J. Pérez-Fornieles, J.A. Vílchez, P. Martínez-Hernández, D.A. Pascual-Figal

Background Anemia is common in patients with chronic heart failure (CHF) and is associated with a worse prognosis. This study aims to identify the biological mechanisms which reflect evolutionary changes in the hemoglobin concentrations in heart failure patients who are still not anaemic. Methods Fifty-nine patients (54±14years, 83% males) with CHF (LVEF 28±10%), who did not have anemia, and had not received any previous transfusions, were included. The parameters studied were: iron metabolism (ferritin, iron, transferrin, soluble transferrin receptor (sTfR), hepcidin); inflammation (C-reactive protein, soluble TNF? receptor I (sTNFRI), interleukin 6); and myocardial stress (NT-proBNP, high sensitivity TnT, growth differentiation factor 15). All parameters were measured on inclusion and 1year after inclusion. Results Baseline hemoglobin (g/dL) was 14.7±1.5 and at 1year of follow-up it showed a significant decrease of ?0.4 (RIC: ?0.7 to ?0.06) (p =0.02). At baseline, only the sTNFRI was a predictor of a decrease in hemoglobin 1year later (p =0.007). During follow-up, the increase in sTNFRI (p =0.002, r =?0.39) and hepcidin (p =0.006, r =?0.35) were both associated with a decrease in hemoglobin. Similarly, the patients who became anemic (13%) had higher levels of hepcidin (p =0.001) and sTNFRI (p =0.008). The remaining parameters did not show any relationship with the evolution in the hemoglobin. Conclusions In CHF patients without anemia, the increase in the inflammatory state (sTNFRI) and the following deterioration in the iron metabolism (hepcidin) were the main determinants of a decrease in hemoglobin and the appearance of anemia in the long term follow-up period.

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Posted on 27 May 2012 | 1:15 am

Different manufacturers of syringes: A new source of variability in blood gas, acid–base balance and related laboratory test?

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Gabriel Lima-Oliveira, Giuseppe Lippi, Gian Luca Salvagno, Martina Montagnana, Geraldo Picheth, Gian Cesare Guidi

Objective Evaluate whether four different brands/types of heparin coated syringes can represent a source of variability in blood gas analysis (BGA). Design and methods Blood was collected from one hundred volunteers into different syringes: Syringe I (lithium heparin and calcium balanced); Syringe II: in-house prepared (sodium heparin); Syringe III: (spray-dried calcium-balanced lithium heparin); Syringe IV (lyophilized electrolyte-balanced lithium heparin). Results Significant differences were as follows: a) Syringe I vs II: pO2, sO2, pCO2 ^t, cHCO3 ^?, ctCO2, base excess (BE), total hemoglobin (tHb), sodium (Na⁺), potassium (K⁺), calcium (Ca²⁺), glucose (Glu), lactate (Lac), O2 Hb and p 50; b) Syringe I vs III: pH, pO2, cHCO3 ^?, ctCO2, BE, Na⁺, Glu, Lac and p 50; c) Syringe I vs IV: pH, pO2, sO2, pCO2 ^t, BE, Na⁺, K⁺, Ca²⁺, Glu, Lac and O2 Hb; d) Syringe II vs III: pH, pO2, sO2, pCO2 ^t, cHCO3 ^?, ctCO2, ctO2, tHb, Na⁺, K⁺, Ca²⁺, Lac and p 50; e) Syringe II vs IV: pH, pO2, sO2, pCO2 ^t, cHCO3 ^?, ctCO2, BE, tHb, Na⁺, K⁺, Ca²⁺, Lac, O2 Hb and p 50; f) Syringe III vs IV: pH, pO2, sO2, cHCO3 ^?, ctCO2, ctO2, BE, Na⁺, K⁺, Ca²⁺, O2 Hb and p 50. Conclusion The different manufacturers of syringes can represent new source of variability on BGA.

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Posted on 27 May 2012 | 1:15 am

Unexpected interference of baby wash products with a cannabinoid (THC) immunoassay

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Steven W. Cotten, Daniel L. Duncan, Elizabeth A. Burch, Carl J. Seashore, Catherine A. Hammett-Stabler

Objectives The results of newborn drug screening have far-reaching impact not only in healthcare, but also in the legal domain. Therefore, the accuracy of these results cannot be undervalued. When false positive cannabinoid (THC) screening results for this population were suspected at our institution, a multidisciplinary approach was initiated to evaluate the screening process for any pre-analytical or analytical sources of error or interference. Design and methods Mixtures of drug-free urine with various commercial products and materials that commonly contact newborns in our nursery were prepared and tested using the immunoassay screening methods in our laboratory. Additional commercial products were similarly tested; and when available, individual surfactants common to the interfering products were also evaluated. Results Addition of Head-to-Toe Baby Wash to drug-free urine produced a dose dependent measureable response in the THC immunoassay. Addition of other commercially available baby soaps gave similar results, and subsequent testing identified specific chemical surfactants that reacted with the THC immunoassay. Conclusion We have identified commonly used soap and wash products used for newborn and infant care as potential causes of false positive THC screening results. Such results in this population can lead to involvement by social services or false child abuse allegations. Given these consequences, it is important for laboratories and providers to be aware of this potential source for false positive screening results and to consider confirmation before initiating interventions. Most importantly, we demonstrate the need for active involvement in the “total testing process,” as sources of error are not confined to the laboratory walls.

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Performance evaluation of the Helena V8 capillary electrophoresis system

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Jessica Poisson, Yuri Fedoriw, Matthew P.A. Henderson, Shirley Hainsworth, Kenneth Tucker, Zia Uddin, Christopher R. McCudden

Objectives To compare the performance characteristics of the Helena V8® and Sebia CAPILLARYS2® automated capillary electrophoresis systems to agarose gel serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) using the Helena SPIFE3000®. Design and methods Serum protein electrophoresis and immunosubtraction was performed on 100 consecutive patient samples comparing two capillary-electrophoresis platforms with agarose-gel SPE and IFE; IFE was used as the gold standard. Chart review was performed on patients where results were discordant between methods. Analytical precision was determined using Sebia's normal and abnormal controls. Results The sensitivities of the CAPILLARYS2, V8, and SPIFE3000 agarose gel for identification of monoclonal gammopathies were respectively 97.4 (95%CI 91.1–100), 92.3 (95%CI 82.2–100), and 89.9 (95%CI 79.1–97.6). The specificities of the CAPILLARYS2, V8, and SPIFE3000 agarose gel were respectively 57.6 (95%CI 45.0–70.2), 72.2 (95%CI 61.0–83.3), and 75.4 (95%CI 60–82.8). These analytical performance characteristics were statistically equivalent between systems (P >0.05). The analytical precision of the capillary-based methods was also statistically equivalent. Chart review of available data from discordant samples revealed that 7/10 patients had a history of multiple myeloma or known monoclonal gammopathy and were being treated or monitored. All discordant samples had low concentration monoclonal proteins (<0.3g/dL). Both capillary-based methods performed poorly (collectively <50% accuracy) at detecting low concentration non-IgG antibodies (IgA, IgM, and light chain monoclonal gammopathies) compared to IFE. Conclusions The Helena V8 and Sebia CAPILLARYS2 were analytically equivalent to the SIFE3000 for identification of IgG monoclonal gammopathies >0.3g/dL. Interpreters using the automated immunotyping/immunosubstraction systems performed poorly at detecting low concentration and non-IgG monoclonal gammopathies.

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Posted on 27 May 2012 | 1:15 am

A Systematized Interdisciplinary Nutritional Care Plan Results in Improved Clinical Outcomes

Publication year: 2012
Source:Clinical Biochemistry

Christopher Lee, James Rucinski, Larry Bernstein

Objective This study investigated identification and treatment of patients at-risk for malnutrition and extended inpatient length of stay. Design Data were collected retrospectively from the medical records for a period of six months. The records were reviewed for: (1) adherence to RD recommendation, (2) decreasing serum albumin during hospital stay, (3) length of hospital stay, (4) readmission within 30days, (5) age, (6) gender, (7) past medical history, (8) primary and secondary diagnoses, (9) the presence or absence of a diet order and (10) medications. Subjects and participants Medical records were reviewed for diagnoses associated with nutrition-related complications. Patient's records were excluded for length of stay less than four days, or in-hospital death. Results The mean LOS was ten days shorter when the advice was followed (p=0.0074). Conclusions Patients at high nutritional risk have a shorter LOS and have fewer complications when the RD advice is followed.

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Posted on 27 May 2012 | 1:15 am

Soluble C-X-C chemokine ligand 16 levels are increased in gout patients

Publication year: 2012
Source:Clinical Biochemistry

Qi Gong, Fan Wu, Xuebo Pan, Jiawen Yu, Tingting Lu, Xiaokun Li, Zhuofeng Lin

Objectives Soluble C-X-C chemokine ligand 16 (CXCL16) was shown to recruit polymorphonuclear cells into synovial tissue in gout patients. The aim of this study was to explore the pathophysiological characteristics of CXCL16 in gout patients with or without chronic kidney disease (CKD). Design and methods 42 gout patients, 22 CKD and 20 healthy subjects were enrolled. Plasma CXCL16 and other biochemical parameters were tested. Results Plasma CXCL16 levels in gout subjects with CKD were significantly increased compared with healthy, CKD and gout subjects without CKD. Soluble CXCL16 levels in gout subjects were closely correlated with renal function and lipid profiles, and independently associated with 24h proteinuria, creatinine clearance rate and C-reactive protein. Conclusion Our data indicated that plasma CXCL16 levels are significantly increased in gout patients with and without CKD, and are independently associated with renal function. Elucidating the pathophysiologcial role of CXCL16 in gout patients requires further study.

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Role of mitochondria in nonalcoholic fatty liver disease-from origin to propagation

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Ignazio Grattagliano, Ornella de Bari, Telma C. Bernardo, Paulo J. Oliveira, David Q.-H. Wang, Piero Portincasa

Objectives Mitochondria play a major role in cell energy-generating processes and integrate several signalling pathways to control cellular life and death. Design and methods Several liver diseases are characterized by mitochondrial alterations which are directly or indirectly dependent on the activation of intracellular stress cascades or receptor-mediated pathways. This article examines the role of mitochondrial dysfunction in critical initiating or propagating events in fatty liver infiltration and nonalcoholic fatty liver disease (NAFLD). Genetic variants and the role of drug-induced toxicity have been considered. Results Key alterations of mitochondrial physiology associated with hepatocyte fatty changes are described. The value of novel non-invasive diagnostic methods to detect mitochondrial metabolic alterations is also discussed. Conclusions Mitochondrial metabolic remodeling is a predominant factor in the appearance and perpetuation of hepatocyte fat accumulation. Non-invasive techniques to identify mitochondrial dysfunction and proper mitochondria protection are two necessary clinical steps for an efficient management of NAFLD.

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Spectrophotometric assay for serum glutathione transferase: A re-examination

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Raffaele Fabrini, Alessio Bocedi, Renato Massoud, Giorgio Federici, Giorgio Ricci

Objectives The aim of the present paper is a careful re-examination of an automated spectrophotometric procedure for glutathione transferase (GST) activity in human serum described previously and used in many laboratories. Design and methods GST activity in human serum has been assayed spectrophotometrically under various experimental conditions. Recombinant human GSTs and specific inhibitors were also used to check the possible occurrence of artifacts. Results Basal level of the enzyme calculated using this method turns out to be much higher than that found using RIA and ELISA procedures. Relevant pH-dependent artifacts deeply affect this spectrophotometric assay. Notably, spectral changes previously interpreted as a measure of basal activity, are mainly due to an increase of the spontaneous reaction between the two substrates. Conclusion GST activity in normal serum cannot be correctly determined with the spectrophotometric assay described previously because of the very low enzyme concentration and the pH-dependent artifacts.

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Posted on 27 May 2012 | 1:15 am

Detection of a novel splicing mutation causing analbuminemia in a Libyan family

Publication year: 2012
Source:Clinical Biochemistry

Amina Bibi, Latifa Jouini, Chaima Abdelhafidh Sahli, Sondess Hadj Fredj, Kamel Abidi, Lamia Gharsallah, Sondess Mathlouthi, Faida Ouali, Hajer Siala, Raja Belhaj, Azza Sammoud, Taieb Messaoud

Background and objectives Analbuminemia is a very rare autosomal recessive disorder. It is an allelic heterogeneous defect caused by a variety of mutations within the albumin gene. We describe in this report two new cases of analbuminemia in Libyans. Design and methods The 14 coding exons of the human serum albumin (HSA) gene and their intron–exon junctions were PCR amplified. The products were screened for mutations by Denaturing High Performance Liquid Chromatography (DHPLC). Samples with altered DHPLC profiles were sequenced. Results DNA sequencing revealed the presence of a novol homozygous G?T transition in the first base of intron 11 (c.1428+1G>T), in both children. This mutation destroys the GT consensus donor sequence found at the 5? end of most intervening sequences and would cause the defective pre-mRNA splicing. Conclusion Molecular diagnosis based on DHPLC and DNA sequencing represents a powerful tool to study molecular defects causing analbuminemia.

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Dyslipidemia and oxidative stress in sarcoidosis patients

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Jasmina Ivaniševi?, Jelena Kotur-Stevuljevi?, Aleksandra Stefanovi?, Zorana Jeli?-Ivanovi?, Slavica Spasi?, Jelica Videnovi?-Ivanov, Violeta Vu?ini?-Mihailovi?, Jasmina Ili?

Objectives Sarcoidosis is an inflammatory disease characterised by enhanced production of reactive oxygen species and alterations in the circulating lipid profile. Both attributes are thought to play a role in its pathogenesis. However, current knowledge regarding the significance of blood oxidative stress/anti-oxidant defence as well as alterations in lipid status parameters in sarcoidosis is scarce. The aim of our study was to assess these parameters and their inter-relationships, as well as their potential for patient-control discrimination. Design and methods Oxidative stress status and anti-oxidant defence parameters were determined in serum and erythrocytes and lipid status parameters were assessed in the serum of 213 treated sarcoidosis patients and 90 controls. Results Malondialdehyde, superoxide anion, total oxidant status, prooxidant–antioxidant balance and triglycerides were significantly higher whereas total anti-oxidant status, superoxide dismutase activity and HDL-cholesterol were significantly lower in sarcoidosis patients compared with controls. Total sulfhydryl group content was higher in patients compared with controls. Serum and erythrocyte malondialdehyde exhibited the strongest ability to predict disease presence. Elevated oxidative stress was characterised by higher clinical accuracy compared with lipid status abnormality. Some oxidative stress and lipid status markers were significantly associated in sarcoidosis. Conclusions Sarcoidosis is characterised by increased oxidative stress, diminished overall anti-oxidative protection and alterations in the circulating lipid profile. Both oxidative stress and lipid status parameters demonstrated the potential to discriminate sarcoidosis from controls which was particularly evident from the point of view of oxidative stress status parameters. Association between these parameters may indicate an increased risk for atherosclerosis development.

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Posted on 27 May 2012 | 1:15 am

Association among retinol-binding protein 4, small dense LDL cholesterol and oxidized LDL levels in dyslipidemia subjects

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Jia Wu, Yong-hui Shi, Dong-mei Niu, Han-qing Li, Chun-ni Zhang, Jun-jun Wang

Objectives To investigate retinol-binding protein 4 (RBP4), small dense low-density lipoprotein cholesterol (sdLDL-C) and oxidized low-density lipoprotein (ox-LDL) levels and their associations in dyslipidemia subjects. Design and methods We determined RBP4, sdLDL-C, ox-LDL levels in 150 various dyslipidemia subjects and 50 controls. The correlation analysis and multiple linear regression analysis were performed. Results The RBP4, sdLDL-C and ox-LDL levels were found increased in various dyslipidemia subjects. The sdLDL-C levels were positively correlated with RBP4 (r=0.273, P =0.001) and ox-LDL (r=0.273, P =0.001). RBP4 levels were also correlated with ox-LDL (r=0.167, P =0.043). The multiple regression analysis showed that only sdLDL-C was a significant independent predictor for RBP4 (? coefficient=0.219, P =0.009; adjusted R² =0.041) and ox-LDL (? coefficient=0.253, P =0.003; adjusted R² =0.057) levels, respectively. Conclusions The independent associations of sdLDL-C with RBP4 and ox-LDL were observed in dyslipidemia subjects. RBP4 may play an important role in lipid metabolism of atherosclerosis, particularly in formation of sdLDL.

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Posted on 27 May 2012 | 1:15 am

An integrated system for monitoring the quality of sample transportation

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

M. Zaninotto, A. Tasinato, A. Padoan, G. Vecchiato, A. Pinato, L. Sciacovelli, M. Plebani

Objectives Due to the consolidation of laboratory testing facilities, there is an increasing need for systems able to assure quality and safety in biological sample transportation, although little evidence on this aspect is available in literature. Design and methods An integrated system for sample transportation, implemented and monitored over a five-year period by our team, consists of secondary and tertiary containers, a device for temperature and time recording, and a system manager allowing the acceptance or rejection of biological samples through the immediate visualization and validation of registered data. Results Data collected between 2009 and October 2011, after a preliminary phase for optimizing the temperature inside the containers, demonstrated the frequency of transportations at an acceptable temperature (<20°C) had increased and that of transportations at an excessively high temperature (>25°C) had decreased by ~80%. Conclusions The integrated system and related operating instructions allow improvement in the quality of sample transportation over time.

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Posted on 27 May 2012 | 1:15 am

Beta-catenin promoter polymorphism is associated with asthma risk in Korean subjects

Publication year: 2012
Source:Clinical Biochemistry

Sungmin Bae, Haeyong Lee, Byoung Whui Choi, Hyeong-Kyu Lee, Sang-In Chung, Wonyong Kim, Kijeong Kim, Seong Jun Seo, Dong-Seok Kim, Seok-min Kim, Yoosik Yoon

Objectives The effects of ?-catenin promoter haplotypes on its mRNA expression levels and asthma risks were investigated in Korean subjects. Design and methods The genotype analyses were conducted by a Taqman method for 684 Korean subjects, 400 controls and 284 with asthma. Measurement of mRNA expression levels in peripheral blood nucleated cells were conducted on subjects whose buffy coat fractions were available (n=185). Logistic regression analyses were conducted to test the associations of the ?-catenin promoter haplotypes with asthma risks. Results Four SNPs, ?10,288C>T (rs7630377), ?6,426C>G (rs9859392), ?4,361G>C (rs9870255), and ?765G>A (rs3864004), were identified in the promoter region of the ?-catenin gene, and three common haplotypes were constructed from them. Haplotype ht1[CCGG] was associated with decreased ?-catenin mRNA expression levels and a lower asthma risk with an odds ratio of 0.53, while ht2[TGCA] was associated with increased mRNA expression levels and a higher asthma risk with an odds ratio of 2.34. Ht3[TCGG] had no significant effects on both. Conclusions Our findings show that ?-catenin promoter polymorphism affects its mRNA expression levels, and also is significantly associated with the asthma risk of Korean subjects.

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Posted on 27 May 2012 | 1:15 am

The effects of freeze–thaw on ?-trace protein and ?2-microglobulin assays after long-term sample storage

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Stephen P. Juraschek, Josef Coresh, Lesley A. Inker, Gregory P. Rynders, John H. Eckfeldt, Elizabeth Selvin

Objectives To evaluate the effect of a freeze–thaw cycle on ?-trace protein (?TP) and ?2-microglobulin (?2M). Design and methods We compared ?TP and ?2M concentrations before and after a single freeze–thaw cycle in long-term stored samples from 172 participants of the Third National Health and Nutrition Examination Survey (NHANES III). Results Measurements of ?TP and ?2M before and after freeze–thaw were highly correlated with Spearman's coefficients of 0.90 and 0.99, respectively. Serum concentrations of ?TP were slightly lower after freeze–thaw (?0.05mg/L, P =0.006). Measurements of ?2M did not differ before and after freeze–thaw (P =0.35). Conclusions ?TP and ?2M measurements were robust to a single freeze–thaw cycle, although ?2M appeared more stable than ?TP. These results have implications for future studies of these biomarkers.

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Posted on 27 May 2012 | 1:15 am

Diagnostic and prognostic significance of human kallikrein 11 (KLK11) mRNA expression levels in patients with laryngeal cancer

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Christos Patsis, Ioannis Yiotakis, Andreas Scorilas

Objectives Human kallikrein 11 gene (KLK11) encodes a secreted serine protease. In view of its diagnostic and prognostic strength in many malignancies, we investigated the mRNA expression levels of KLK11 in laryngeal tissues in order to unveil its clinical usefulness in laryngeal cancer. Design and methods KLK11 expression was quantified in 163 tissue samples from 105 laryngeal cancer patients with the development of a highly sensitive real-time PCR methodology, using SYBR Green® chemistry. Results KLK11 expression in laryngeal cancer specimens of primary or recurrent nature was significantly inferior compared with their non-malignant counterparts (P <0.001 and P =0.026, respectively), a finding of immense diagnostic value as illustrated in the ROC curve analyses (P <0.001). Survival analysis showed that patients harboring KLK11-positive tumors had a significantly decreased risk of death (HR=0.26, P =0.042). Conclusions Our data recommend KLK11 mRNA expression as a novel and independent biomarker in laryngeal cancer for diagnostic and prognostic purposes.

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Posted on 27 May 2012 | 1:15 am

Diurnal variation in lipoprotein-associated phospholipase A2 (Lp-PLA2)

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Leonard A. Kaminsky, Cemal Ozemek

Objectives The aim of our study was to determine the diurnal variation of lipoprotein-associated phospholipase A2 (Lp-PLA2), an arterial-specific inflammatory enzyme implicated in the formation of vulnerable, rupture-prone plaque that can identify individuals at high risk for cardiovascular disease. Presently, the diurnal variation of Lp-PLA2 is not known. Design and Methods Ten men and 8 women (age range: 22–76years) had a blood sample taken every 4h over a 24-hour time period. Samples were analyzed for both Lp-PLA2 mass and activity. Results The mean coefficient of variation (CV) for Lp-PLA2 mass was 5.9% (ranges from 2.5 to 9.4%) for the 18 subjects. Similarly, the mean CV for Lp-PLA2 activity was 3.7% (ranges from 1.2 to 6.8%). There were no significant correlations between CV and any of the subject characteristics. Conclusions The diurnal variation of Lp-PLA2 mass and activity is similar to that of well accepted lipoprotein risk factors. With the relatively low diurnal variability, there does not appear to be a need to make sure serial measurements of Lp-PLA2 mass and activity are taken at the same time of the day.

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Posted on 27 May 2012 | 1:15 am

Editorial Board

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Posted on 27 May 2012 | 1:15 am

Stability of 1,25-dihydroxyvitamin D2 and 1,25-dihydroxyvitamin D3 in human serum

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Joe M. El-Khoury, Sihe Wang

Posted on 27 May 2012 | 1:15 am

Plasma concentrations but not serum concentrations of brain-derived neurotrophic factor are related to pro-inflammatory cytokines in patients undergoing major abdominal surgery

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

G. Chimienti, A. Mezzapesa, M.T. Rotelli, L. Lupo, G. Pepe

Objectives To investigate peripheral brain-derived neurotrophic factor (BDNF) concentrations in the perioperative period, their relationship with transforming growth factor-?1 (TGF-?1 tumour necrosis factor-? (TNF-?), interleukin-6 (IL-6) and IL-6 genetics. Design and methods Prospective, observational study. BDNF, TGF-?1, IL-6 and TNF-? were analysed at baseline (T0), 5h (T1), 24h (T2) and 5days (T3) after surgery, in 21 patients. The IL-6 ?174 G/C polymorphism was genotyped. Results Serum BDNF concentrations decreased (P =0.048), correlated with TGF-?1 (r=0.610 at T1, r=0.493 at T2, r=0.554 at T3). Plasma BDNF concentrations raised (P =0.049), correlated with IL-6 and TNF-? at T1 (r=0.495 and r=0.441, respectively). BDNF response was predictable from TNF-? and IL-6 concentrations and the IL-6 ?174 G/C genotype. Conclusion Serum and plasma BDNF concentrations could relate to platelet activation and inflammatory response, respectively. IL-6 genetics played a role in the BDNF acute response.

Posted on 27 May 2012 | 1:15 am

Erratum to “The expression of HSPs, anti-oxidants, and cytokines in plasma and bronchoalveolar lavage fluid of patients with acute respiratory distress syndrome” [Clin. Biochem. 45 (2012) 493–498]

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Eun Joo Lee, Ji-Youn Lim, Sang Yeub Lee, Seung Hyeon Lee, Kwang Ho In, Se Hwa Yoo, Donggeun Sul, Sanghoon Park

Posted on 27 May 2012 | 1:15 am

Position Statement of the Canadian Society of Clinical Chemists and Canadian Association of Medical Biochemists on Hemoglobin A1c Measurement and Reporting

Publication year: 2012
Source:Clinical Biochemistry

Curtis J. Oleschuk, Connie Prosser, Kent Dooley, Treffor Higgins, Qing Meng, Andrew Don-Wauchope, Lei Fu, Peter Bunting, Ken Onuska, Raymond LePage, Pascal Pelletier, Ihssan Bouhtiauy, Ed Randell

Posted on 27 May 2012 | 1:15 am

Changes of blood platelet adhesion to collagen and fibrinogen induced by homocysteine and its thiolactone

Publication year: 2012
Source:Clinical Biochemistry

Joanna Malinowska, Ma?gorzata Tomczynska, Beata Olas

Background Mechanisms of homocysteine (Hcy) and its derivatives contribution to thrombosis are complex and only partly recognized. The available data suggest that the prothrombic properties of homocysteine and its thiolactone (HTL) may be not only a result of the changes in coagulation process, fibrinolysis, endothelial dysfunction, but also the dysfunction of blood platelets. Objective and methods The present work was designed to study the effects of Hcy and HTL on one of the step of platelet activation – the platelet adhesion to collagen and fibrinogen (measured by ELISA method) in vitro. Platelet suspensions were preincubated with Hcy and HTL, at the final concentrations of 10, 25, 50 and 100?M, and 0.1, 0.2 and 1?M, respectively. Then, for platelet activation thrombin (0.1 U/ml) or TRAP (20?M), were used. Results The performed assays demonstrated that Hcy (at high tested concentrations: 50 and 100?M) and its thiolactone (at all used concentrations: 0.1, 0.2 and 1?M) stimulated the adhesion of thrombin- or TRAP- activated platelets to collagen and fibrinogen. Moreover, the exposure of blood platelets to HTL (even at lower concentrations than Hcy) resulted the stronger modulatory effect on the platelet adhesion than when blood platelets were treated with Hcy. Conclusion In conclusion, the results obtained in this study demonstrate that Hcy and its thiolactone may affect adhesive properties of blood platelets.

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Fetuin-A serum levels are not correlated to kidney function in long-lived subjects

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Chiara Bellia, Rossella Tomaiuolo, Antonietta Caruso, Bruna Lo Sasso, Federica Zarrilli, Ciriaco Carru, Maria Deiana, Angelo Zinellu, Sara Pinna, Giuseppe Castaldo, Luca Deiana, Marcello Ciaccio

Objectives Serum Fetuin A has been identified as an inhibitor of ectopic calcification. It is reduced in subjects with chronic kidney disease (CKD) and it has been proposed as a potential link between CKD and the higher prevalence of arterial calcification observed in these patients. During aging both the stiffening of arterial wall due to calcification and a decline in kidney function are frequent. The aim of the study is to investigate if Fetuin A serum levels are associated with aging and with AHSG T256S polymorphism. Moreover, we aim at investigate whether serum Fetuin A is correlated to kidney function in this setting of senescence. Design and methods 256 health long-lived subjects (age 92 [81–100]) were recruited for the study. Serum Fetuin A was evaluated by ELISA, Cystatin C by immune-nephelometry. AHSG T256S was determinated by PCR-RFLP. Results Serum Fetuin A shows a significant correlation with age (r =0.20; P =0.0048). AHSG TS and SS genotypes are associated to lower levels of serum protein (0.27 [0.19–0.29] g/L vs 0.42 [0.32–0.49] g/L; P <0.027 and 0.34 [0.25–0.41] g/L vs 0.42 [0.32–0.49] g/L; P <0.001, respectively). No significant correlation between Fetuin A and Cystatin C was observed. Conclusions Serum Fetuin A increases with age in elder individuals and subjects with the TS or SS AHSG polymorphism have lower levels of the circulating protein. No correlation with kidney function decline was observed. Other mechanisms should be investigated to explain the increase of Fetuin A with age.

Highlights

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Reference intervals for reproductive hormones in prepubertal children on the automated Roche cobas e 411 analyzer

Publication year: 2012
Source:Clinical Biochemistry

Ivana Zec, Ivana Ku?ak, Ilijana Beg?evi?, Ana-Maria Šimundi?, Dubravka Tišlari?-Medenjak, Željka Bukovec Megla, Nada Vrki?

Objectives To establish reference intervals for luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), progesterone (P), total and free testosterone (T) and sex-hormone binding globulin (SHBG) in prepubertal children and to assess age- and gender-related differences. Design and methods A total of 948 subjects, 480 girls and 468 boys, between 1 to 11years of age, were included in this study. All assays were performed on a Roche cobas e 411 immunoassay analyzer. Reference intervals have been evaluated according to the most recent CLSI guidelines. Results Median values of LH, FSH and T were significantly higher in subgroups ranging from ?8 to <11years, for both genders. In girls of that age, reference values of E2 were significantly higher than in younger ones, and in boys of the corresponding age. Conclusion Established reference intervals are applicable to other laboratories that use the same instrumentation.

Highlights

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Development of an immunoassay for differentiating human immunodeficiency virus infections — from vaccine-induced immune response in Tiantan vaccine trials in China

Publication year: 2012
Source:Clinical Biochemistry

Zuowei Yuan, Weixian Chen, Juan Zhang, Jun Zhang, Tingxiu Xiang, Jieli Hu, Zhijuan Wu, Xi Du, Ailong Huang, Jian Zheng

Objective To develop a Rapid Flow-through assay for distinguishing replicating Tiantan vaccine-generated serological response from true HIV infection. Design and method A Rapid Flow-through Test including gp41, gp36, sk1, sk2 and sk3 antigens was established and the performance of the assay was evaluated in clinical studies and compared with ELISA assay. Results Sk1, sk2 and sk3 peptides performed at 100% specificity and slightly but not significantly different sensitivities between ELISA assay (92%, 76% and 41%) and Flow-through Test Kit (92%, 75% and 40%) in diagnosing HIV-1 infections. Of particular importance, Tiantan vaccine recipients that gave false-positive results in gp41 serodetection scored negative for sk1, sk2 and sk3 antibodies. Conclusion The Rapid Flow-through Test could be a robust tool in both diagnosing HIV-1/2 infections and differentiating between vaccines induced immunity and immunity resulting from natural exposure, thus serving as potential implementation in HIV vaccine trials.

Highlights

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Cathepsin D activity in nasal polyps

Publication year: 2012
Source:Clinical Biochemistry

Katarzyna Paw?owska-Góral, Jaros?aw Markowski, Piotr Wardas, Ewa Kurzeja, Ma?gorzata Witkowska

Objectives The aim of the study was to assess the activity of cathepsin D in polyps removed during first-time FESS surgery and in recurrent polyps removed during successive FESS surgeries. Design and Methods The study examined 24 polyps: 11 polyps were removed during first-time surgical procedures (termed primary polyps in the study), and 13 recurrent polyps were removed in successive FESS surgeries (termed polyps after re-polypectomy in the study). The activity of cathepsin D was determined by measuring the tyrosine released from denatured hemoglobin. Result The average cathepsin D activity in polyps after re-polypectomy was 74% higher than the average activity in primary polyps, whereas the difference between the maximum and the minimum cathepsin D activities in polyps after re-polypectomy was twofold greater than the respective difference in primary polyps. Conclusion Differences in cathepsin activity and the protein content, likely to be significant in the process of polyp recurrence, were observed in both groups of polyps.

Highlights

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Effect of the interleukin-1B gene on serum oxidized low-density lipoprotein levels

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Maria Fernanda Manica-Cattani, Marta Maria Medeiros Frescura Duarte, Euler Esteves Ribeiro, Raul de Oliveira, Ivana Beatrice Mânica da Cruz

Objectives To investigate the association of the +3953 IL-1B gene polymorphism in healthy subjects with serum oxidized LDL (oxLDL) levels. Design and methods We selected 255 subjects who were non-smokers and who had no cardiovascular or other chronic degenerative diseases, and we measured the oxLDL and other glucose levels, lipid biomarkers and biological variables that are related to cardiovascular metabolism. The +3953 IL-1B gene polymorphism was determined using molecular genetics techniques (PCR-RFLP). Results A significant association among the +3953 IL-1B genotypes and the oxLDL level was observed. The TT genotype presented lower oxLDL levels than the other genotypes. A multivariate analysis showed that this result was independent of the sex, age, obesity and hypertension status of the subjects. Conclusions Our results suggest that the IL-1B gene polymorphism affects the modulation of serum oxLDL levels.

Highlights

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Distinguishing pancreatic cancer from chronic pancreatitis and healthy individuals by 1H nuclear magnetic resonance-based metabonomic profiles

Publication year: 2012
Source:Clinical Biochemistry

Lin Zhang, Haifeng Jin, Xuegang Guo, Zhao Yang, Lina Zhao, Shanhong Tang, Ping Mo, Kaichun Wu, Yongzhan Nie, Yanglin Pan, Daiming Fan

Objectives To develop a noninvasive and accessible diagnostic method for pancreatic cancer (PC). Design and methods We presented a metabolomic method, pattern recognition techniques applied to ¹H nuclear magnetic resonance (¹H NMR) spectra, to investigate the plasma metabolites obtained from 19 patients with PC, 20 patients with chronic pancreatitis (CP) and 20 healthy individuals. Results Metabolic changes associated with PC included abnormal amino acid and lipid metabolism, and possible multiple metabolic syndrome. PC elevated plasma levels of N-acetyl glycoprotein (NAG), dimethylamine (DMA), very low density lipoprotein (VLDL), and acetone, and reduced levels of 3-hydroxybutyrate, lactate, high density lipoprotein (HDL), low density lipoprotein (LDL), citrate, alanine, glutamate, glutamine, histidine, isoleucine, lysine, and valine. These metabolites could be a biomarker group for PC that distinguishes between PC and CP patients and healthy individuals. Conclusions NMR-based metabonomic strategy appears as a promising approach for distinguishing pancreatic cancer and identifying new strategies for prevention or therapy in the clinical practice.

Highlights

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Diagnostic utility of a single-epitope sandwich B-type natriuretic peptide assay in stable coronary artery disease: Data from the Akershus Cardiac Examination (ACE) 1 Study

Publication year: 2012
Source:Clinical Biochemistry

Helge Røsjø, Natalia N. Tamm, Gunnhild Kravdal, Karina R. Seferian, Arne Didrik Høiseth, Ståle Nygård, Pirouz Badr, Ragnhild Røysland, Torbjørn Omland

Objectives To assess the merit of a novel single-epitope sandwich (SES) assay specific to the stable part of BNP in patients with reversible myocardial ischemia as post-translational modifications of BNP may influence assay performance. Design and methods We measured BNP concentration by a conventional assay and the SES-BNP assay in 198 patients referred for myocardial perfusion imaging (MPI). BNP concentration was determined before and immediately after exercise stress testing, and 1.5 and 4.5h later. Patients were categorized according to MPI results. Results BNP concentration was higher with both assays at all time points in patients with reversible myocardial ischemia (n =19) compared to the other patients (n =179). Measuring BNP after stress testing or calculating the changes in BNP concentration did not improve diagnostic accuracy compared to baseline measurements: SES-BNP: AUC 0.71 (95% CI 0.58–0.84) vs. conventional BNP: 0.71 (0.59–0.83), p =0.96. By linear regression analysis, reversible myocardial ischemia was significantly associated with baseline SES-BNP concentration (p =0.043), but not with measurements by the conventional assay (p =0.089). In multivariate logistic regression models, only baseline measurement with the SES-BNP assay was significantly associated with reversible myocardial ischemia: odds ratio [logarithmical transformed BNP] 2.00 (95% CI 1.16–3.47), p =0.013. The SES-BNP assay, but not the conventional BNP assay, reclassified a significant proportion of the patients towards their correct category on top of the best clinical model of our data set: NRI=0.47, p =0.04. Conclusions The SES-BNP assay was significantly associated with reversible myocardial ischemia as assessed by several statistical indices, while a conventional BNP assay was not.

Highlights

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Determination of calprotectin in gingival crevicular fluid by immunoassay on a microchip

Publication year: 2012
Source:Clinical Biochemistry

Jun-ichi Kido, Kaori Abe, Shouki Yatsushiro, Mika Bando, Yuka Hiroshima, Toshihiko Nagata, Toshihiko Ooie, Masato Tanaka, Masatoshi Kataoka

Objectives Gingival crevicular fluid (GCF) contains calprotectin, which appears to be a useful biomarker for periodontal diseases because of its high level in GCF from periodontally diseased pockets. To determine calprotectin in GCF that has a very small volume, sandwich enzyme-linked immunosorbent assay (ELISA) on a microchip was performed and its utility was estimated. Design and methods Anti-calprotectin primary antibody was discharged on a microchip using a piezoelectric inkjet printing system. Calprotectin standard and calprotectin in GCF samples from eleven subjects were determined by the ELISA method with the prepared microchip and their values were compared with those obtained by conventional ELISA. Results Using the ELISA on a microchip, a reasonable standard curve of calprotectin protein (1.56–100ng/mL) was obtained. Calprotectin in GCF samples was quantified and showed reasonable values in accordance with the condition of periodontal diseases. The values determined by the microchip method and conventional ELISA showed a significant linear relationship (R ² =0.981). Conclusions Calprotectin in GCF was determined using the ELISA on a microchip with high efficiency and this ELISA method for calprotectin determination may become a useful method for diagnosing periodontal diseases.

Highlights

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Clinical significance of inflammatory and fibrogenic cytokines in diabetic nephropathy

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Hala O. El Mesallamy, Hanaa H. Ahmed, Atef A. Bassyouni, Amira S. Ahmed

Objectives To study the role of inflammatory chemokine; monocyte chemoattractant protein-1 (MCP-1), and fibrogenic markers [transforming growth factor beta-1 (TGF-?1), connective tissue growth factor (CTGF) and fibronectin (FN)] in diabetic nephropathy (DN). Design and methods This study included 17 control and 65 type 2 diabetic subjects (18 normoalbuminuric, 22 microalbuminuric and 25 macroalbuminuric). Demographic characteristics, diabetic index and kidney function tests were monitored. Serum TGF-?1, plasma CTGF, MCP-1 and FN levels were assayed. Results Microalbuminuric and macroalbuminuric subjects showed a significant elevation in TGF-?1, CTGF, MCP-1 and FN levels as compared with control and normoalbuminuric subjects. There was positive correlation between these markers and fasting plasma glucose, albumin excretion rate and with each other. Conclusion This study revealed the importance of these markers in DN pathogenesis which is powered by their association and thus the possibility of their use as biochemical markers in DN was suggested.

Highlights

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NTproBNP concentrations in healthy children

Publication year: 2012
Source:Clinical Biochemistry

G. Koerbin, W.P. Abhayaratna, J.M. Potter, S. Apostoloska, R.D. Telford, P.E. Hickman

Introduction There have been limited studies generating BNP and NT-proBNP reference intervals for paediatric populations. We prospectively assessed NT-proBNP levels in a cohort of 854 healthy school children from the Lifestyle of Our Kids (LOOK) prospective longitudinal study. Materials and methods NT-proBNP analysis was performed on 172 girls and 212 boys with average age 8.1years, 183 girls and 181 boys, average age 10.1years and 183 girls and 180 boys with average age 11.9years. Data were stratified according to age and gender with the median, range of results and 2.5th and 97.5th percentiles calculated Results There were no significant differences between males and females at any of the 3 study ages. Significant differences were seen between the 8 and 12year-olds, 10 and 12year-olds and the 8 and 12year-old boys. Discussion Our study demonstrated that NT-proBNP concentrations in healthy children progressively decline between ages 8 and 12years. Our selection of unambiguously healthy children produced similar median but lower 97.5th percentile NT-proBNP concentrations to previously published studies.

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Calcium and bone

Publication year: 2012
Source:Clinical Biochemistry

Kun Zhu, Richard L. Prince

Objective Evaluate the role of calcium on bone health. Methods Review of literatures on calcium and bone development during childhood and bone health in adulthood and older age. Results Calcium intake influences skeletal calcium retention during growth and thus affects peak bone mass achieved in early adulthood. Increased calcium intake is associated with increased bone mineral accretion rate up to a threshold level in all ethnic groups. The minimum intake to achieve maximal retention is 1140mg/day for white boys and 1300mg/day for white girls. Calcium also plays a role in preventing bone loss and osteoporotic fractures in later life. Meta-analyses report that calcium supplementation reduce bone loss by 0.5–1.2% and the risk of fracture of all types by at least 10% in older people. Low calcium intake is a widespread problem across countries and age groups. Conclusion Adequate calcium intake throughout lifetime is important for bone health and the prevention of osteoporosis and related fractures.

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Analytical evaluation of Sysmex UF-1000i for flow cytometric analysis of peritoneal fluid

Publication year: 2012
Source:Clinical Biochemistry

Sabrina Buoro, Rosanna Gustinetti, Paola Dominoni, Maria Grazia Alessio, Patrizia Filisetti, Maria Grazia Lucà, Stefano Fagiuoli, Cosimo Ottomano, Giuseppe Lippi

Objective To evaluate analytical performance of Sysmex UF-1000i for peritoneal fluid analysis. Methods Functional sensitivity, imprecision, linearity and comparison studies were performed on peritoneal fluids. Results Total imprecision was 1.6–4.7%, functional sensitivity 27/?L for white blood cell (WBC) and 32/?L for total nucleated cell (TNC) count. Linearity was excellent up to 983cell/?L, carry-over <0.2%, correlation with manual microscopy always greater than 0.992. Conclusion The instrument exhibited optimal performance at the conventional WBC diagnostic thresholds.

Highlights

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Awakening salivary cortisol levels of children with sleep bruxism

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Paula Midori Castelo, Taís de Souza Barbosa, Luciano José Pereira, Fernando Luiz Affonso Fonseca, Maria Beatriz Duarte Gavião

The study of factors potentially associated with sleep bruxism (SB) may contribute to a better understanding of its nature and etiology. Objectives In this way, this cross-sectional study aimed to evaluate the association between SB and salivary cortisol levels, heart rate, and other parafunctional habits. Design and methods Data were collected in 100 healthy caries-free children of both genders, aged 7.23±0.60years, with (n=27) and without (n=73) signs and symptoms of SB by interview with the parents and clinical and physical examination. Salivary cortisol was measured immediately after waking up and 30min after awakening for the determination of the area under the response curve (AURC). Data were analyzed by descriptive statistics, normality test, and Spearman correlation test; a stepwise logistic regression model was used to verify the association between SB, as the dependent variable, and age, gender, body mass index (BMI), heart rate, presence of sucking habit, nail biting, enuresis, and AURC (? =0.05). Results AURC did not correlate with BMI and heart rate. Only AURC showed a significant negative association with SB, while age, gender, BMI, heart rate and other parafunctional habits did not associate with SB. Conclusion In the studied sample, children with SB were more likely to present low concentrations of awakening salivary cortisol.

Highlights

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Plasma high sensitivity C-reactive protein and its relationship with cytokines levels in children with newly diagnosed type 1 diabetes and ketoacidosis

Publication year: 2012
Source:Clinical Biochemistry

Kyriaki Karavanaki, Kostas Kakleas, Soultana Georga, ?nastasia Bartzeliotou, George Mavropoulos, Manolis Tsouvalas, Alice Vogiatzi, Ioannis Papassotiriou, Christina Karayianni

Background High-sensitivity C-reactive protein (hs-CRP) and pro-inflammatory cytokines have been suggested as sensitive markers of endothelial dysfunction. Our aim was to monitor plasma hs-CRP levels at different time-points and in different degrees of ketoacidosis severity, its association with cytokine levels and its role as a marker of severe ketoacidosis complications. Patients and methods We studied in 38 newly diagnosed children with type 1 diabetes and ketoacidosis, aged 7.7±3.1years, hs-CRP, white blood cell count (WBC), and plasma levels of cytokines IL-1? (interleukin-1?), IL-2, IL-6, IL-8, IL-10, TNF-? (tumor necrosis factor-?) prior to and during DKA management. Results On admission, the levels of WBC, PMN, IL-6 and IL-10 were elevated, but were all reduced within 120h after ketoacidosis management. In the group with moderate/severe ketoacidosis, but not in mild ketoacidosis, hs-CRP levels were significantly reduced at 24h (p =0.021), WBC and IL-6 at 120h (p =0.003), while IL-10 was prematurely reduced at 6–8h (p =0.008). Moreover hs-CRP was significantly associated with WBC (p =0.023) and IL-6 (p =0.028) on admission, with IL-6 (p =0.002) and IL-8 (p =0.014) at 24h and with IL-10 (p =0.027) at 120h. The above were not observed in the group with mild ketoacidosis. Conclusions In the children with moderate/severe diabetic ketoacidosis of our study, increased levels of hs-CRP and IL-6 were observed, together with leukocytosis and neutrophilia, without the presence of infection. As hs-CRP was found to be strongly associated with the inflammatory IL-6, the prolonged elevation of hs-CRP levels in children with severe ketoacidosis could serve as a marker for the development of its severe complications.

Highlights

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Fracture risk assessment

Publication year: 2012
Source:Clinical Biochemistry

Eugene McCloskey, Helena Johansson, Anders Oden, John A. Kanis

Having traditionally relied on measurements of bone mineral density, it is now established that the consideration of other risk variables improves the categorisation of fracture risk. Whereas several models are available, the FRAX models are the most extensively used. The approach uses easily obtained clinical risk factors to estimate 10year fracture probability, with or without femoral neck bone mineral density (BMD), to enhance fracture risk prediction. It has been constructed and validated using primary data from population based cohorts around the world, including centres from North America, Europe, Asia and Australia. The FRAX® tool should not be considered as a gold standard, but rather as a platform technology on which to build as new validated risk indicators become available. Notwithstanding, the present models provide an aid to enhance patient assessment by the integration of clinical risk factors alone and/or in combination with BMD.

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Diagnostic accuracy of biomarkers measured in the hepatic vein and peripheral vein in the prediction of advanced fibrosis in patients with chronic viral hepatitis

Publication year: 2012
Source:Clinical Biochemistry

Ki Tae Suk, Dong Joon Kim, Chang Hoon Kim, Seung Ha Park, Jae Youn Cheong, Sung Won Cho, Jong Young Choi, Kwang Hyub Han, Ho Taik Sung, So Hyung Hong, Dae Yong Kim, Jai Hoon Yoon, Yeon Soo Kim, Gwang Ho Baik, Jin Bong Kim

Objectives The accuracies of biomarkers checked in the hepatic vein (HV) and peripheral vein (PV) were compared in the prediction of advanced fibrosis (AF) of liver. Methods Patients with chronic viral hepatitis (n=101) who underwent hepatic venous pressure gradient, liver biopsy, and paired HV–PV samples (6 biomarkers: hyaluronic acid [HA], haptoglobin, matrix metalloproteinase-2 [MMP2], tissue inhibitor of metalloproteinases-1 [TIMP1], procollagen III N-terminal peptide [PIIINP], and apolipoprotein-A1 [Apo-A1]) were enrolled. Results Differences were displayed between the HV and PV in the predictive logit-models for predicting AF (?3.13+0.017×MMP2?0.019×haptoglobin and ?0.270+0.007×HA?0.018×haptoglobin, respectively). In the area under the receiver operating characteristic curves, PIIINP (0.74/0.68, p =0.03), MMP2 (0.72/0.63, p =0.04), HA (0.79/0.76, p =0.94), Apo-A1 (0.56/0.48, p =0.73), and predictive logit-model (0.81/0.78, p =0.68) showed higher diagnostic value in the HV sample. Conclusions While most biomarkers were correlated better with hepatic fibrosis in HV than in PV, individually and in predictive logit-models, they were inadequate to determine the degree of advanced fibrosis.

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Preliminary evidence of a reduced serum level of fibroblast growth factor 19 in patients with biopsy-proven nonalcoholic fatty liver disease

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Fatih Eren, Ramazan Kurt, Fatih Ermis, Ozlen Atug, Nese Imeryuz, Yusuf Yilmaz

Objectives We sought to determine whether serum concentrations of fibroblast growth factor 19 (FGF19) – an ileum-derived enterokine which plays a role in the control of glucose and lipid homeostasis – are altered in patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD). Design and methods Serum levels of FGF19 were measured using enzyme-linked immunosorbent assay in 91 patients with biopsy-proven NAFLD and 74 controls. Results FGF19 levels were significantly lower in patients with biopsy-proven NAFLD (median: 130pg/mL) than in controls (median: 210pg/mL, P <0.001). Serum FGF19 levels were significantly but modestly associated with hepatocyte ballooning scores in univariate analysis (r=?0.25, P <0.05) but not after adjustment for potential confounders (?=?0.18; t=1.78, P =0.08). Conclusions This pilot study suggests that serum FGF19 levels are decreased in patients with NAFLD but are not independently associated with liver histology findings.

Highlights

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Rapid urinary trypsinogen-2 test in the early diagnosis of acute pancreatitis: A meta-analysis

Publication year: 2012
Source:Clinical Biochemistry

Kai Chang, Weiping Lu, Kejun Zhang, Shuangrong Jia, Fake Li, Feng Wang, Shaoli Deng, Ming Chen

Objectives Urinary trypsinogen-2 has been implicated as a promising biomarker for the early diagnosis of acute pancreatitis (AP). The meta-analysis was used to establish the overall accuracy of urinary trypsinogen-2 test for diagnosing AP. Methods Based on comprehensive searches of the PubMed and Embase databases, we identified and abstracted outcome data from all articles evaluating the diagnostic value of urinary trypsinogen-2. A summary estimate for sensitivity, specificity, 95% confidence region and 95% prediction region was calculated using the bivariate random-effects approach. Results The meta-analysis included 13 studies (2342 patients, the proportion of severe AP from 13.21% to 30.00%). Overall, the pooled sensitivity was 82.3% (95%CI 79.3%–85.1%) and specificity was 93.5% (95%CI 92.2%–94.6%). The diagnostic odds ratios (DOR) was 85.23 (95%CI 40.14–180.99). The area under the summary ROC curve (AUC) was 0.9673. Conclusion The urinary trypsinogen-2 test is a reliable and rapid method for the early diagnosis of AP.

Highlights

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HBV and HCV infections in Wilson's disease patients: Copper overload could be protective?

Publication year: 2012
Source:Clinical Biochemistry

M. Liggi, M. Sini, O. Sorbello, A. Civolani, L. Demelia

Posted on 27 May 2012 | 1:15 am

Acute and chronic regulation of circulating PTH: Significance in health and in disease

Publication year: 2012
Source:Clinical Biochemistry

Pierre D'Amour

Circulating human parathyroid hormone (PTH) is immunoheterogenous. It is composed of 80% carboxyl-terminal (C) fragments and of 20% PTH(1–84). This composition contrasts with the biological activity of the hormone, which is only related to PTH(1–84), creating a paradox between circulating PTH composition and PTH bioactivity. PTH molecular forms are either secreted by the parathyroid glands or generated by the peripheral metabolism of PTH(1–84) in the liver. The kidney has a major role in the disposal of C-PTH fragments. Secretion of PTH molecular forms by the parathyroid glands is highly regulated under a variety of clinical conditions, suggesting that C-PTH fragments could exert some biological effects of their own. Recent data suggest that C-PTH fragments can exert biological actions opposite to those of PTH(1–84) by acting on a C-PTH receptor not yet cloned. They can decrease calcium concentration, phosphate excretion, bone resorption and 1,25(OH)2 synthesis. The clinical implications of this new concept are reviewed.

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Transcutaneous bilirubin measurement: Comparison of Respironics BiliCheck and JM-103 in a normal newborn population

Publication year: 2012
Source:Clinical Biochemistry, Volume 45, Issue 9

Costantino Romagnoli, Enrico Zecca, Piero Catenazzi, Giovanni Barone, Antonio Alberto Zuppa

Objectives To compare the accuracy of BiliCheck™ (Respironics, Marietta, GA) and Konica-Minolta Air Shield JM-103 (Drager Medical Inc, Telford, PA) to evaluate total serum bilirubin (TSB). Methods Prospective blinded study comparing two diagnostic devices in 630 neonates requiring TSB measurement. Results Linear regression analysis showed a good correlation between BiliCheck™ and TSB (r =0.8212) as well as between JM-103 and TSB (r =0.8686). BiliCheck shows a tendency to underestimate TSB. The mean difference in TSB–TcB was ?1.4mg/dL for BC (?4.7/+1.8mg/dL) and 0.3mg/dL for JM-103 (?2.6/+3.2mg/dL). ROC analysis for TSB?12mg/dL showed area under the curve for BiliCheck™ significantly lower than those for JM-103 (p <0.0001). JM-103 resulted less time expensive than BiliCheck. Conclusions In spite of similar diagnostic accuracy JM-103 could be preferred for some practical advantages, but its suitability in performing universal screening for severe hyperbilirubinemia deserves further investigations.

Highlights

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Validation of methylation-sensitive high resolution melting for the detection of DNA methylation in cholangiocarcinoma

Publication year: 2012
Source:Clinical Biochemistry

Rattaya Amornpisutt, Ruethairat Sriraksa, Temduang Limpaiboon

Objectives To validate methylation-sensitive high resolution melting (MS-HRM) for detection of DNA methylation. Design and Methods Methylation of two independent loci, OPCML and DcR1, was analyzed in cholangiocarcinoma and adjacent normal samples by using MS-HRM, methylation-specific PCR and pyrosequencing. Results There was significant agreement between methods at both loci. Conclusions MS-HRM represents the excellent potential and reliability for quantifying DNA methylation levels in clinical samples.

Highlights

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