Thromboelastographic evaluation of the effectiveness of choline or CDP-choline treatment on endotoxin-induced hemostatic alterations in dogs

Sepsis/endotoxemia associates with coagulation abnormalities. We showed previously that exogenous choline treatment reversed the changes in platelet count and function as well as prevented disseminated intravascular coagulation (DIC) in endotoxemic dogs. The aim of this follow-up study was to evaluate the effect of treatment with choline or cytidine-5'-diphosphocholine (CDP-choline), a choline donor, on endotoxin-induced hemostatic alterations using thromboelastography (TEG). Dogs were randomized to six groups and received intravenously (iv) saline, choline (20 mg/kg) or CDP-choline (70 mg/kg) in the control groups, whereas endotoxin (0.1 mg/kg, iv) was used alone or in combination with choline or CDP-choline at the same doses in the treatment groups. TEG variables including R- and K-time (clot formation), maximum amplitude (MA) and α-angle (clot stability), G value (clot elasticity), and EPL, A, and LY30 (fibrinolysis), as well as overall assessment of coagulation (coagulation index - CI), were measured before and at 0.5-48 h after the treatments. TEG parameters did not change significantly in the control groups, except for CI parameter after choline administration. Endotoxemia resulted in increased R-time and A value (P < 0.05), decreased K-time (P < 0.05), α-angle (P < 0.001) and CI values (P < 0.01) at different time points. Treatment with either choline or CDP-choline attenuated or prevented completely the alterations in TEG parameters in endotoxemic dogs with CDP-choline being more effective. These results confirm and extend the effectiveness of choline or CDP-choline in endotoxemia by further demonstrating their efficacy in attenuating or preventing the altered viscoelastic properties of blood clot measured by TEG.

Choline or CDP-choline restores hypotension and improves myocardial and respiratory functions in dogs with experimentally - Induced endotoxic shock

Endotoxin shock is associated with severe impairments in cardiovascular and respiratory functions. We showed previously that choline or cytidine-5'-diphosphocholine (CDP-choline) provides beneficial effects in experimental endotoxin shock in dogs. The objective of the present study was to determine the effects of choline or CDP-choline on endotoxin-induced cardiovascular and respiratory dysfunctions. Dogs were treated intravenously (i.v.) with saline or endotoxin (LPS, 0.1 mg/kg) 5 min before i.v. infusion of saline, choline (20 mg/kg) or CDP-choline (70 mg/kg). Blood pressure, cardiac rate, myocardial and left ventricular functions, respiratory rate, blood gases, serum electrolytes and cardiac injury markers were determined before and at 0.5-48 h after endotoxin. Plasma tumor necrosis factor alpha (TNF-α), high mobility group box-1 (HMGB1), catecholamine and nitric oxide (NO) levels were measured 2 h and 24 h after the treatments. Endotoxin caused immediate and sustained reductions in blood pressure, cardiac output, pO₂ and pH; changes in left ventricular functions, structure and volume parameters; and elevations in heart rate, respiratory rate, pCO2 and serum electrolytes (Na, K, Cl, Ca and P). Endotoxin also resulted in elevations in blood levels of cardiac injury markers, TNF-α, HMGB1, catecholamine and NO. In choline- or CDP-choline-treated dogs, all endotoxin effects were much smaller in magnitude and shorter in duration than observed values in controls. These data show that treatment with choline or CDP-choline improves functions of cardiovascular and respiratory systems in experimental endotoxemia and suggest that they may be useful in treatment of endotoxin shock in clinical setting.

Comparison of reference intervals derived by direct and indirect methods based on compatible datasets obtained in Turkey

BACKGROUND

Indirect derivation of reference intervals (RIs) from the laboratory information system (LIS) has been recently pursued. We aimed at evaluating the accuracy of indirectly predicted RIs compared to the RIs established directly from healthy subjects in the nationwide RI study in Turkey, targeting 25 major chemistry analytes.

METHODS

LIS data were retrieved from the laboratory that performed measurements for the direct study. They were cleaned by limiting to outpatients with age 18-65 years, and by allowing only one record per year per patient. Evaluated were four indirect methods of univariate approach: Hoffmann, Bhattacharya, Arzideh, and Wosniok methods. Power transformation of the LIS dataset was performed either using the power (λ) reported by the IFCC global RI study (the first two methods) or using a λ predicted (the last two).

RESULTS

Compared to the direct study dataset, the LIS dataset showed a variable degree of alterations in peak location and shape. Consequently, lower-side peak-shifts observed in sodium, albumin, etc. led to lowered RI limits, whereas higher-side peak-shift observed in triglyceride, low-density lipoprotein cholesterol, etc. led to raised RI limits. Overall, 72% (62-81) of the RI limits predicted by indirect methods showed significant biases from direct RIs. However, the biases observed in total cholesterol, lactic dehydrogenase, etc. were attributed to a higher-side age-bias in LIS dataset. After excluding them, the overall proportion of biased RIs was reduced to 47% (38-54).

CONCLUSION

To reduce prediction biases that remained after age adjustment, it is necessary to apply more rigorous data-cleaning before applying indirect methods.

Big data and reference intervals: rationale, current practices, harmonization and standardization prerequisites and future perspectives of indirect determination of reference intervals using routine data

Reference intervals are commonly used as a decision-making tool. In this review, we provide an overview on "big data" and reference intervals, describing the rationale, current practices including statistical methods, essential prerequisites concerning data quality, including harmonization and standardization, and future perspectives of the indirect determination of reference intervals using routine laboratory data.

Stability of hematological analytes during 48 hours storage at three temperatures using Cell-Dyn hematology analyzer

Background

The complete blood count (CBC) with differential leukocyte count (DLC) is one of the most common tests requested by physicians. The results of this test are affected by storage temperature and time of incubation. This study was designed to evaluate the stability of hematologic parameters in blood specimens stored for 48 h at three temperatures.

Methods

K2-EDTA - blood was collected from 22 healthy adults. The CBC was performed using a hematology analyser immediately; 0 time point and at 4, 8, 12, 16, 20, 24, and 48 h after storage at 4 °C, 10 °C or 23 °C. Changes in values of CBC parameters from the 0 time point were determined and reported as % of the initial value.

Results

Red blood cells, platelet, hemoglobin, and mean corpuscular hemoglobin were found stable during 48 h storage at 4 °C, 10 °C or 23 °C. Hematocrite and mean corpuscular volume increased, while white blood cells decreased at 48 h when stored at 23 °C. Lymphocytes, neutrophils, eosinophils, and basophils showed significant differences after 12 h of storage at 23 °C.

Conclusions

Red blood cells, platelet, hemoglobin, and mean corpuscular hemoglobin are the only suitable parameters without refrigeration during 24 h storage. When CBC and DLC are performed, 4 °C can be recommended as the most suitable storage temperature for 12 h storage.

Verification of reference intervals in routine clinical laboratories: practical challenges and recommendations

Reference intervals (RIs) are fundamental tools used by healthcare and laboratory professionals to interpret patient laboratory test results, ideally enabling differentiation of healthy and unhealthy individuals. Under optimal conditions, a laboratory should perform its own RI study to establish RIs specific for its method and local population. However, the process of developing RIs is often beyond the capabilities of an individual laboratory due to the complex, expensive and time-consuming process to develop them. Therefore, a laboratory can alternatively verify RIs established by an external source. Common RIs can be established by large, multicenter studies and can subsequently be received by local laboratories using various verification procedures. The standard approach to verify RIs recommended by the Clinical Laboratory Standards Institute (CLSI) EP28-A3c guideline for routine clinical laboratories is to collect and analyze a minimum of 20 samples from healthy subjects from the local population. Alternatively, "data mining" techniques using large amounts of patient test results can be used to verify RIs, considering both the laboratory method and local population. Although procedures for verifying RIs in the literature and guidelines are clear in theory, gaps remain for the implementation of these procedures in routine clinical laboratories. Pediatric and geriatric age-groups also continue to pose additional challenges in respect of acquiring and verifying RIs. In this article, we review the current guidelines/approaches and challenges to RI verification and provide a practical guide for routine implementation in clinical laboratories.

New-generation fish oil and olive oil lipid for prevention of oxidative damage in preterm infants: Single center clinical trial at university hospital in Turkey

BACKGROUND

Parenteral nutrition (PN) has been widely used in preterm infants. The lipid solutions used for PN, however, are associated with oxidative stress and morbidity. The aim of this study was to compare the effectiveness of a new-generation lipid emulsion (SMOFLipid) and olive-oil based lipid emulsion for prevention of PN-associated oxidative damage.

METHODS

Preterm infants < 32 weeks of gestational age were included in this prospective randomized study. All infants were randomized to SMOFlipid or olive-oil based lipid emulsion (ClinOleic). Lipid peroxidation products were evaluated in all infants. In addition, total antioxidant capacity (TAC), and both pro- and anti-inflammatory cytokines were studied at days 0, 7 and 14.

RESULTS

A total of 89 infants (SMOFlipid, n = 42; ClinOleic, n = 47) were enrolled. TAC was higher in the SMOFlipid group compared with the ClinOleic group at all time points, and the difference on day 7 was statistically significant. Although the anti-inflammatory cytokine interleukin-10 was higher in the SMOFlipid group, this difference was not significant. Bronchopulmonary dysplasia (BPD) was lower in the SMOFlipid group (14.1%) than in the ClinOleic group (31.2%), but this finding was non-significant p > 0.05. The rate of severe BPD was significantly lower in the SMOFlipid group.

CONCLUSION

To our best of knowledge, this is the first study to suggest that SMOFlipid might decrease oxidative damage and oxidative-stress-associated morbidity compared with olive oil-based emulsion in preterm infants.

Indirect methods for reference interval determination - review and recommendations

Reference intervals are a vital part of the information supplied by clinical laboratories to support interpretation of numerical pathology results such as are produced in clinical chemistry and hematology laboratories. The traditional method for establishing reference intervals, known as the direct approach, is based on collecting samples from members of a preselected reference population, making the measurements and then determining the intervals. An alternative approach is to perform analysis of results generated as part of routine pathology testing and using appropriate statistical techniques to determine reference intervals. This is known as the indirect approach. This paper from a working group of the International Federation of Clinical Chemistry (IFCC) Committee on Reference Intervals and Decision Limits (C-RIDL) aims to summarize current thinking on indirect approaches to reference intervals. The indirect approach has some major potential advantages compared with direct methods. The processes are faster, cheaper and do not involve patient inconvenience, discomfort or the risks associated with generating new patient health information. Indirect methods also use the same preanalytical and analytical techniques used for patient management and can provide very large numbers for assessment. Limitations to the indirect methods include possible effects of diseased subpopulations on the derived interval. The IFCC C-RIDL aims to encourage the use of indirect methods to establish and verify reference intervals, to promote publication of such intervals with clear explanation of the process used and also to support the development of improved statistical techniques for these studies.

Diurnal variation of steroid hormones and their reference intervals using mass spectrometric analysis

OBJECTIVE

Accurate measurement of steroid hormones remains challenging. Mass spectrometry affords a reliable means for quantitating steroid profiles accurately. Our objective was to establish and define (1) the extent of diurnal fluctuations in steroid concentrations that potentially necessitate strict adherence to time of sample acquisition and (2) time-dependent steroid reference intervals.

DESIGN

Nine steroid markers were examined in couplets in males and females.

METHODS

Using isotope dilution high-performance liquid chromatography-tandem mass spectrometric (LC-MS/MS) analysis, we developed a multi-steroid profile requiring only a minimal volume of serum (0.1 mL). Couplet (AM and PM) measurements of steroid hormones for 120 healthy females (F) and 62 healthy males (M) were obtained. Patients were recruited from several participating centers.

RESULTS

The following diurnal values were noted to be significantly different in both females and males: cortisone, cortisol, corticosterone, 11 deoxycortisol (11 DOC), androstenedione, 17a-hydroxyprogesterone (17 OHP) and dehydroepiandrosterone (DHEA). Testosterone was only found to have significant diurnal variance in males. Progesterone showed no significant difference in AM and PM values for either groups and thus may provide an internal control.

CONCLUSIONS

When diagnosing endocrine disorders, it is imperative to acknowledge the 24-h diurnal variation of the biochemical steroid markers. We highlight the importance of standardization of collection times and appropriate implementation of reference intervals.

PRECIS

We identify diurnal fluctuations in steroid concentrations with time of day and emphasize the importance of adhering to firm time of sample acquisition.

Reference Intervals: Comparison of Calculation Methods and Evaluation of Procedures for Merging Reference Measurements From Two US Medical Centers

OBJECTIVES

To analyze consistency of reference limits and widths of reference intervals (RIs) calculated by six procedures and evaluate a protocol for merging intrainstitutional reference data.

METHODS

The differences between reference limits were compared with "optimal" bias goals. Also, widths of the RIs were compared. RIs were calculated using Mayo-SAS quantile, EP Evaluator, and four International Federation of Clinical Chemistry and Laboratory Medicine methods: parametric and nonparametric (NP) with and without latent abnormal values exclusion (LAVE). Regression parameters from cotested samples were evaluated for harmonizing intrainstitutional reference data.

RESULTS

Mayo-SAS quintile, LAVE(-)NP, and EP Evaluator generated similar RIs, but these RIs often were wider than RIs from parametric procedures. LAVE procedures generated narrower RIs for nutritional and inflammatory markers. Transformation with regression parameters did not ensure homogeneity of merged data.

CONCLUSIONS

Parametric methods are recommended when inappropriate values cannot be excluded. The nonparametric procedures may generate wider RIs. Data sets larger than 200 are recommended for robust estimates. Caution should be exercised when merging intrainstitutional data.

Distinguishing reference intervals and clinical decision limits - A review by the IFCC Committee on Reference Intervals and Decision Limits

Reference Intervals (RIs) and clinical decision limits (CDLs) are a vital part of the information supplied by laboratories to support the interpretation of numerical clinical pathology results. RIs describe the typical distribution of results seen in a healthy reference population while CDLs are associated with a significantly higher risk of adverse clinical outcomes or are diagnostic for the presence of a specific disease. However, as the two concepts are sometimes confused, there is a need to clarify the differences between these terms and to ensure they are easily distinguished, especially because CDLs have a clinical association with specific diseases and risks, thereby implying that effective clinical interventions are available. It is important to note that, because population-based RIs are derived from the range of values expected in a typical community population, laboratory results that fall outside a RI do not necessarily indicate a disease but rather that additional medical follow-up and/or treatment may be warranted. In contrast, CDLs are associated with a risk of specific adverse outcomes, and are commonly used to interpret laboratory test results, including lipid parameters, glucose, hemoglobin A1c (HbA1c), and tumor markers, to determine risk of disease, to diagnose or to treat. In recent years, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Committee on Reference Intervals and Decision Limits (C-RIDL) has focused primarily on RIs and has performed multicenter studies to obtain common RIs. However, the broader responsibility of the Committee, from its name, includes "decision limits". C-RIDL now aims to emphasize the importance of the correct use of both RIs and CDLs and to encourage laboratories to specify the appropriate information to clinicians as needed. This review discusses RIs and CDLs in detail, describes the similarities and the differences between these two important tools in laboratory medicine, and clearly explains the processes used to define them. C-RIDL encourages the involvement of laboratory professionals in the establishment of both RIs and CDLs.

A nationwide multicentre study in Turkey for establishing reference intervals of haematological parameters with novel use of a panel of whole blood

INTRODUCTION

A nationwide multicentre study was conducted to establish well-defined reference intervals (RIs) of haematological parameters for the Turkish population in consideration of sources of variation in reference values (RVs).

MATERIALS AND METHODS

K2-EDTA whole blood samples (total of 3363) were collected from 12 laboratories. Sera were also collected for measurements of iron, UIBC, TIBC, and ferritin for use in the latent abnormal values exclusion (LAVE) method. The blood samples were analysed within 2 hours in each laboratory using Cell Dyn and Ruby (Abbott), LH780 (Beckman Coulter), or XT-2000i (Sysmex). A panel of freshly prepared blood from 40 healthy volunteers was measured in common to assess any analyser-dependent bias in the measurements. The SD ratio (SDR) based on ANOVA was used to judge the need for partitioning RVs. RIs were computed by the parametric method with/without applying the LAVE method.

RESULTS

Analyser-dependent bias was found for basophils (Bas), MCHC, RDW and MPV from the panel test results and thus those RIs were derived for each manufacturer. RIs were determined from all volunteers' results for WBC, neutrophils, lymphocytes, monocytes, eosinophils, MCV, MCH and platelets. Gender-specific RIs were required for RBC, haemoglobin, haematocrit, iron, UIBC and ferritin. Region-specific RIs were required for RBC, haemoglobin, haematocrit, UIBC, and TIBC.

CONCLUSIONS

With the novel use of a freshly prepared blood panel, manufacturer-specific RIs' were derived for Bas, Bas%, MCHC, RDW and MPV. Regional differences in RIs were observed among the 7 regions of Turkey, which may be attributed to nutritional or environmental factors, including altitude.

A reference interval study for common biochemical analytes in Eastern Turkey: a comparison of a reference population with laboratory data mining

Introduction

The aim of this study was to define the reference intervals (RIs) in a Turkish population living in Northeast Turkey (Erzurum) for 34 analytes using direct and indirect methods. In the present study, the regional RIs obtained were compared with other RI studies, primarily the nationwide study performed in Turkey.

Materials and methods

For the direct method, 435 blood samples were collected from a healthy group of females (N = 218) and males (N = 217) aged between 18 and 65 years. The sera were analysed in Ataturk University hospital laboratory using Roche reagents and analysers for 34 analytes. The data from 1,366,948 records were used to calculate the indirect RIs using a modified Bhattacharya method.

Results

Significant gender-related differences were observed for 17 analytes. There were also some apparent differences between RIs derived from indirect and direct methods particularly in some analytes (e.g. gamma-glutamyltransferase, creatine kinase, LDL-cholesterol and iron). The RIs derived with the direct method for some, but not all, of the analytes were generally comparable with the RIs reported in the nationwide study and other previous studies in Turkey.There were large differences between RIs derived by the direct method and the expected values shown in the kit insert (e.g. aspartate aminotransferase, total-cholesterol, HDL-cholesterol, and vitamin B12).

Conclusions

These data provide region-specific RIs for 34 analytes determined by the direct and indirect methods. The observed differences in RIs between previous studies could be related to nutritional status and environmental factors.

Reference intervals: current status, recent developments and future considerations

Reliable and accurate reference intervals (RIs) for laboratory analyses are an integral part of the process of correct interpretation of clinical laboratory test results. RIs given in laboratory reports have an important role in aiding the clinician in interpreting test results in reference to values for healthy populations. Since the 1980s, the International Federation of Clinical Chemistry (IFCC) has been proactive in establishing recommendations to clarify the true significance of the term 'RIs, to select the appropriate reference population and statistically analyse the data. The C28-A3 guideline published by the Clinical and Laboratory Standards Institute (CLSI) and IFCC is still the most widely-used source of reference in this area. In recent years, protocols additional to the Guideline have been published by the IFCC, Committee on Reference Intervals and Decision Limits (C-RIDL), including all details of multicenter studies on RIs to meet the requirements in this area. Multicentric RIs studies are the most important development in the area of RIs. Recently, the C-RIDL has performed many multicentric studies to obtain common RIs. Confusion of RIs and clinical decision limits (CDLs) remains an issue and pediatric and geriatric age groups are a significant problem. For future studies of RIs, the genetic effect would seem to be the most challenging area. 
The aim of the review is to present the current theory and practice of RIs, with special emphasis given to multicenter RIs studies, RIs studies for pediatric and geriatric age groups, clinical decision limits and partitioning by genetic effects on RIs.

A multicenter nationwide reference intervals study for common biochemical analytes in Turkey using Abbott analyzers

BACKGROUND

A nationwide multicenter study was organized to establish reference intervals (RIs) in the Turkish population for 25 commonly tested biochemical analytes and to explore sources of variation in reference values, including regionality.

METHODS

Blood samples were collected nationwide in 28 laboratories from the seven regions (≥400 samples/region, 3066 in all). The sera were collectively analyzed in Uludag University in Bursa using Abbott reagents and analyzer. Reference materials were used for standardization of test results. After secondary exclusion using the latent abnormal values exclusion method, RIs were derived by a parametric method employing the modified Box-Cox formula and compared with the RIs by the non-parametric method. Three-level nested ANOVA was used to evaluate variations among sexes, ages and regions. Associations between test results and age, body mass index (BMI) and region were determined by multiple regression analysis (MRA).

RESULTS

By ANOVA, differences of reference values among seven regions were significant in none of the 25 analytes. Significant sex-related and age-related differences were observed for 10 and seven analytes, respectively. MRA revealed BMI-related changes in results for uric acid, glucose, triglycerides, high-density lipoprotein (HDL)-cholesterol, alanine aminotransferase, and γ-glutamyltransferase. Their RIs were thus derived by applying stricter criteria excluding individuals with BMI >28 kg/m2. Ranges of RIs by non-parametric method were wider than those by parametric method especially for those analytes affected by BMI.

CONCLUSIONS

With the lack of regional differences and the well-standardized status of test results, the RIs derived from this nationwide study can be used for the entire Turkish population.

Utility of a panel of sera for the alignment of test results in the worldwide multicenter study on reference values

BACKGROUND

In a planned International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) worldwide study on reference intervals (RIs), a common panel of serum samples is to be measured by laboratories from different countries, and test results are to be compared through conversion using linear regression analysis. This report presents a validation study that was conducted in collaboration with four laboratories.

METHODS

A panel composed of 80 sera was prepared from healthy individuals, and 45 commonly tested analytes (general chemistry, tumor markers, and hormones) were measured on two occasions 1 week apart in each laboratory. Reduced major-axis linear regression was used to convert reference limits (LL and UL). Precision was expressed as a ratio of the standard error of converted LL or UL to the standard deviation (SD) comprising RI (approx. 1/4 of the RI width corresponding to between-individual SD). The allowable and optimal levels of error for the SD ratio (SDR) were set as ≤0.250 and ≤0.125, respectively, in analogy to the common method of setting limits for analytical bias based on between-individual SD.

RESULTS

The values for the calculated SDRs depended upon the distribution patterns of test results: skewness toward higher values makes SDRLL lower and SDRUL higher. However, the CV of the regression line slope, CV(b), is less affected by skewness. The average of SDRLL and SDRUL (aveSDR) correlates closely with CV(b) (r=0.995). The aveSDRs of ≤0.25 and ≤0.125 corresponds approximately to CV(b) values of ≤11% and ≤5.5%, respectively. For all results (i.e., n=80), conversion was allowable (optimal) in 98% (89%) of the analytes, as judged by CV(b). Resampling studies using random subsets of data with a data size (n) of 70 to 20 revealed that SDRs and CV(b) gradually increase with reduction of n, especially with n ≤30.

CONCLUSIONS

CV(b) is a robust estimator for judging the convertibility of reference values among laboratories, even with a skewed distribution. Assuming 40 sera to be a practical size for the panel, reference values of 89% (80%) of analytes examined were made comparable by regression analysis with the allowable (optimal) level of precision.

Breast milk choline contents are associated with inflammatory status of breastfeeding women

BACKGROUND

Choline is an important component of human breast milk and its content varies considerably among breastfeeding women and lactation periods.

OBJECTIVE

The aim of this study was to assess the relationship between breast milk choline contents and inflammatory status in breastfeeding women.

METHODS

Breast milk choline compounds and serum C-reactive protein (CRP) concentrations were determined in breastfeeding women at 1 to 3 (n = 53) or 22 to 180 (n = 54) days postpartum, expressing colostrum or mature milk, respectively.

RESULTS

Median concentrations of free choline, phosphocholine, glycerophosphocholine, phospholipid-bound choline, and total choline were 71, 38, 96, 194, and 407 µmol/L or 93, 351, 958, 186, and 1532 µmol/L in colostrum or mature milk, respectively. Median serum CRP concentrations were 4.13 mg/L and 0.33 mg/L at 1 to 3 days and 22 to 180 days postpartum, respectively. At 1 to 3 days postpartum, milk free choline, phosphocholine, glycerophosphocholine, and total choline as well as serum CRP concentrations were significantly higher in breastfeeding women who delivered by cesarean section than those who delivered via the vaginal route. Serum CRP concentration was positively correlated with colostrum free choline (r = 0.703; P < .001), phosphocholine (r = 0.759; P < .001), glycerophosphocholine (r = 0.706; P < .001), and total choline (r = 0.693; P < .001), whereas it was negatively correlated (r = -0.442; P < .001) with colostrum phospholipid-bound choline. Serum CRP was also negatively correlated with mature milk free choline (r = -0.278; P < .05), but no correlation was found between serum CRP and other choline compounds in mature milk.

CONCLUSION

These data show that the concentrations of milk choline compounds are associated with inflammatory status of breastfeeding women, particularly during the first few days after delivery.

Do metoclopramide and ondansetrone alter mivacurium-induced neuromuscular blockade? - a randomised trial

BACKGROUND

We aimed to investigate the effects of metoclopramide and ondansetrone on mivacurium neuromuscular blockade.

METHODS

Seventy five, ASA I-II patients, aged 18-65 and scheduled for elective surgery requiring tracheal intubation were included in the study. The patients received metoclopramide 10 mg, ondansetrone 4 mg or normal saline 5 mL; group M, group O, group NS (n=25), respectively. Before anesthesia study drugs were administered in a volume of 5 mL. The level of plasma cholinesterase were obtained before and 5 minutes after the administration of study drugs and 5 minutes after the administration of mivacurium. Onset time, T25, T75, T25-75, T90 levels were compared with each other and differences between each patients were investigated. After recording T90, the study was terminated and surgery was started.

RESULTS

Onset time was significantly shorter in group M, than the other two groups. Onset time in group O was significantly shorter than in group NS. In Group M T25, T75, T90 and recovery indices were significantly greater than in Group NS (p<0.001). In Group O T25, T75 were greater than Group NS (p<0.01 and p<0.05, respectively). In Group M T75, T90 and emergence indices were significantly higher than Group O (p<0.001, p<0.01, p<0.001, respectively). In Groups M and O, plasma cholinesterase levels decreased significantly (p<0.001) after administration of study drugs and mivacurium. Plasma cholinesterase also was reduced in Group NS 5 minutes after the administration of mivacurium (p<0.001).

CONCLUSION

Ondansetrone is believed to be more reliable agent than metoclopramide when used with mivacurium.

Protocol and standard operating procedures for common use in a worldwide multicenter study on reference values

The reference intervals (RIs) given in laboratory reports have an important role in aiding clinicians in interpreting test results in reference to values of healthy populations. In this report, we present a proposed protocol and standard operating procedures (SOPs) for common use in conducting multicenter RI studies on a national or international scale. The protocols and consensus on their contents were refined through discussions in recent C-RIDL meetings. The protocol describes in detail (1) the scheme and organization of the study, (2) the target population, inclusion/exclusion criteria, ethnicity, and sample size, (3) health status questionnaire, (4) target analytes, (5) blood collection, (6) sample processing and storage, (7) assays, (8) cross-check testing, (9) ethics, (10) data analyses, and (11) reporting of results. In addition, the protocol proposes the common measurement of a panel of sera when no standard materials exist for harmonization of test results. It also describes the requirements of the central laboratory, including the method of cross-check testing between the central laboratory of each country and local laboratories. This protocol and the SOPs remain largely exploratory and may require a reevaluation from the practical point of view after their implementation in the ongoing worldwide study. The paper is mainly intended to be a basis for discussion in the scientific community.

Serum levels of leptin, adiponectin and resistin are interrelated and related to total antioxidant capacity, free fatty acids and phospholipids in early neonatal life

OBJECTIVES

The aims of this study were to determine interrelationships between serum leptin, adiponectin and resistin, insulin-like growth factor-1 (IGF-1), total antioxidant capacity (TAC), non-esterified fatty acids (NEFA) and phospholipids concentrations in infants.

DESIGN AND METHODS

A cross-sectional study was conducted to assess serum levels of leptin, adiponectin, resistin, IGF-1, TAC, NEFA and phospholipids in 45 breast-fed infants enrolled at 4-30 days after birth.

RESULTS

Serum leptin and adiponectin concentrations were positively correlated. Serum resistin concentrations were inversely correlated to serum leptin and adiponectin concentrations. Serum TAC was positively correlated to serum leptin and adiponectin, and inversely to serum resistin concentrations. Serum adiponectin concentrations were positively related to serum NEFA and phospholipid concentrations. Serum resistin concentrations were inversely related to serum NEFA, and phospholipid concentrations.

CONCLUSION

These data show that circulatory levels of leptin, adiponectin and resistin are interrelated and they apparently interact with the anti-oxidant system of infants.

Comparison of lipid emulsions on antioxidant capacity in preterm infants receiving parenteral nutrition

BACKGROUND

Although a variety of different lipid emulsions with varying fatty acid contents have been developed, there are some concerns about the administration of these lipid emulsions because of potential adverse effects, including oxidative stress-related morbidity. The aim of the present study was to evaluate and compare the effects of the standard soybean oil-based and olive oil-based i.v. lipid emulsions (ILE) on oxidative stress, determined by total antioxidant capacity (TAC), and to investigate the safety of the use of these two emulsions in terms of biochemical indices.

METHODS

In this prospective study, premature infants were randomly assigned to two groups, each group consisting of 32 patients who received parenteral ILE of either 20% olive oil or 20% soybean oil. They were given ILE for 7 days and then were evaluated with regard to TAC.

RESULTS

No statistically significant difference was observed between the groups in terms of routine biochemical parameters. TAC for both groups on day 7 was significantly lower compared with that on day 0. Although the decrease in TAC within 7 days of ILE administration was greater in the soybean group compared with that in the olive oil group, it was not statistically significant.

CONCLUSIONS

Olive oil-based ILE exhibit similar antioxidant activity and can be used as an alternative to soybean oil-based ILE. TAC significantly decreased in infants following administration of either lipid emulsion, and premature infants tolerated either ILE well, both biochemically and clinically.

Rate of T alleles and TT genotype at MTHFR 677C->T locus or C alleles and CC genotype at MTHFR 1298A->C locus among healthy subjects in Turkey: impact on homocysteine and folic acid status and reference intervals

Methylenetetrahydrofolate reductase (MTHFR) is important for folate and homocysteine (Hcy) metabolism. MTHFR 677C->T and 1298A->C MTHFR are two most common mutations which can affect folate and total homocysteine (tHcy) status. This study was designed to determine the rate of MTHFR 677C->T and 1298A->C mutations, and their influence on serum folate, Hcy and vitamin B12 status and the reference intervals in 402 healthy Turkish adults. The rate of MTHFR 677C->T or 1298A->C mutations was 50.7% or 54.7%, respectively. The MTHFR 677C->T mutation-specific reference intervals for serum folate and tHcy were characterized by marked shifts in their upper limits. In homozygote subjects for MTHFR 677C->T serum folate concentration was lower and serum tHcy concentration was higher than those in the wild genotype; all subjects had lower serum folate and 54% of the subjects had higher tHcy concentrations than the cutoff values of <or=10 nmol/L and >or=12 micromol/L, respectively. Serum vitamin B12 status was similar in all genotypes. Serum tHcy concentrations were inversely correlated with serum folate and vitamin B12 concentrations in all genotypes. These data show that the rate of MTHFR 677C->T and 1298A->C mutations is very high in Turks and serum folate and tHcy status are impaired by these mutations.

Difference in the magnitude of muscle damage between elbow flexors and knee extensors eccentric exercises

The aim of this study was to investigate the difference in the magnitude of muscle damage between maximal eccentric exercises of the elbow flexors (EF) and knee extensors (KE). Twelve sedentary male volunteers participated in the study. Range of motion (ROM), isometric peak torque (IPT), delayed onset of muscle soreness (DOMS), creatine kinase activity (CK), and myoglobin concentration (Mb) were evaluated before, immediately after, and on the 1(st) , 2(nd), 3(rd) , and 7(th) days following exercise. Total work (TW) during exercises was recorded and corrected by muscle volume (TWc). TWc was greater (p < 0.01) for EF [24 (2) joule·cm-3] than for KE [7 (0.4) joule·cm(-3)]. Increases in CK on the 2(nd) , 3(rd) , and 7(th) days (p < 0.01) and increases in Mb on the 1(st) , 2(nd) , 3(rd) , and 7(th) days were significantly (p<0.01) larger for EF than for KE. The decline in IPT was greater (p < 0.05- 0.01) for EF at all test occasions compared with KE. The results of this study demonstrate that the magnitude of muscle damage is greater and the recovery is slower following maximal eccentric exercise of the EF than of the KE for sedentary males. Key pointsThe magnitude of muscle damage is greater and the recovery is slower following maximal eccentric exercise of the EF than of the KE for sedentary males.This may be because of the higher total eccentric work per muscle unit in elbow flexors.