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Background: Current reference values for pediatric dyslipidemia used in China were not developed based on local population studies and did not consider age and sex differences., Objective: In this study, we aimed to determine suitable reference values for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and non-high-density lipoprotein cholesterol (nonHDL-C) for Chinese children and adolescents using a national multicenter school-based study., Methods: A total of 15,830 students aged 6-17 years were recruited from seven provinces of China. Age- and sex-specific percentile values for each lipid indicator were derived based on levels measured in the fasting state, and percentile curves of each indicator were plotted using the LMS method., Results: Serum lipid levels varied considerably with age in both sexes. Among boys, the cut-off value for high TC, nonHDL-C, LDL-C, and TG, based on the value of the 95th percentiles, ranged from 4.58 to 5.39, 3.34 to 3.99, 2.69 to 3.31, and 1.22 to 1.83 mmol/L, respectively; among girls, the cut-off value for high TC, nonHDL-C, LDL-C, and TC ranged from 5.01 to 5.39, 3.66 to 3.97, 2.97 to 3.32, and 1.41 to 1.93 mmol/L, respectively. The cut-point for low HDL-C ranged from 0.84 to 1.08 mmol/L in boys and from 0.89 to 1.04 mmol/L in girls., Conclusion: These findings may help to determine age- and sex-specific reference values for serum lipids among Chinese children and adolescents and provide valuable guidance for screening of dyslipidemia., (Copyright © 2021. Published by Elsevier Inc.)

Lipidomics is a rapidly growing field, fueled by developments in analytical instrumentation and bioinformatics. To date, most researchers and industries have employed their own lipidomics workflows without a consensus on best practices. Without a community-wide consensus on best practices for the prevention of lipid degradation and transformations through sample collection and analysis, it is difficult to assess the quality of lipidomics data and hence trust results. Clinical studies often rely on samples being stored for weeks or months until they are analyzed, but inappropriate sampling techniques, storage temperatures, and analytical protocols can result in the degradation of complex lipids and the generation of oxidized or hydrolyzed metabolite artifacts. While best practices for lipid stability are sample dependent, it is generally recommended that strategies during sample preparation capable of quenching enzymatic activity and preventing oxidation should be considered. In addition, after sample preparation, lipid extracts should be stored in organic solvents with antioxidants at -20 °C or lower in an airtight container without exposure to light or oxygen. This will reduce or eliminate sublimation, and chemically and physically induced molecular transformations such as oxidation, enzymatic transformation, and photon/heat-induced degradation. This review explores the available literature on lipid stability, with a particular focus on human health and/or clinical lipidomic applications. Specifically, this includes a description of known mechanisms of lipid degradation, strategies, and considerations for lipid storage, as well as current efforts for standardization and quality insurance of protocols., (© 2020 AOCS.)

Nanomedicines are well recognised for their ability to improve therapeutic outcomes. Yet, due to their complexity, nanomedicines are challenging and costly to produce using traditional manufacturing methods. For nanomedicines to be widely exploited, new manufacturing technologies must be adopted to reduce development costs and provide a consistent product. Within this study, we investigate microfluidic manufacture of nanomedicines. Using protein-loaded liposomes as a case study, we manufacture liposomes with tightly defined physico-chemical attributes (size, PDI, protein loading and release) from small-scale (1 mL) through to GMP volume production (200 mL/min). To achieve this, we investigate two different laminar flow microfluidic cartridge designs (based on a staggered herringbone design and a novel toroidal mixer design); for the first time we demonstrate the use of a new microfluidic cartridge design which delivers seamless scale-up production from bench-scale (12 mL/min) through GMP production requirements of over 20 L/h using the same standardised normal operating parameters. We also outline the application of tangential flow filtration for down-stream processing and high product yield. This work confirms that defined liposome products can be manufactured rapidly and reproducibly using a scale-independent production process, thereby de-risking the journey from bench to approved product., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Suraj Abraham, Logan Ingalls and Keara Marshall are employees of Precision NanoSystems Inc. Timothy J Leaver is an employee and shareholder of Precision NanoSystems Inc.., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: Suberin, as part of plant protective barriers, is one of the most important natural polymers after cellulose and lignin. For a full elucidation of suberin structure the quantification of glycerol, fatty α,ω-diacids and ω-hydroxyacids, the major building blocks of suberin, is of primary importance. Glycerol is often lost in the most used analytical procedures or rarely determined by deficient or too laborious techniques., Objectives: Propose a simple, accessible and reliable methanolysis work-up procedure for an accurate and simultaneous quantification of glycerol and suberin fatty monomers in the same GC run., Material and Methods: Cork from Quercus suber L. was depolymerised by methanolysis. Glycerol was derivatised to an organic soluble form before the suberin monomers recovery in water/organic solvent partition. Gas chromatography flame ionisation detector (GC-FID) response factors were determined for glycerol, ferulic acid and one for each fatty monomer substructure. Additionally, 1,2,4-butanetriol and methyl nonadecanoate were used as internal standards., Results: The proposed experimental approach allowed the glycerol and all the fatty suberin monomers in the same GC run to be quantified accurately. Glycerol represented 30.6 area%, 14.2 mass% and 38.4 molar% of suberin and the COOH/OH groups ratio was 0.6:1 in the proposed experimental approach in contrast with 0.10 area% and COOH/OH ratio of 3:1 in the most used protocol. Furthermore, ω-hydroxyacids/α,ω-diacids mass ratio was 1:1 as opposed to an area ratio of 1.5:1., Conclusion: The proposed work-up procedure revealed to be a reliable analytical tool for the complete analysis of suberin allowing the future knowledge to grow towards a better understanding of suberin structure throughout its range and variability., (© 2019 John Wiley & Sons, Ltd.)

The physicochemical properties and transfection efficacies of two samples of a cationic lipid have been investigated and compared in 2D (monolayers at the air/liquid interface) and 3D (aqueous bulk dispersions) model systems using different techniques. The samples differ only in their chain composition due to the purity of the oleylamine (chain precursor). Lipid 8 (using the oleylamine of technical grade for cost-efficient synthesis) shows lateral phase separation in the Langmuir layers. However, the amount of attached DNA, determined by IRRAS, is for both samples the same. In 3D systems, lipid 8 p forms cubic phases, which disappear after addition of DNA. At physiological temperatures, both lipids (alone and in mixture with cholesterol) assemble to lamellar aggregates and exhibit comparable DNA delivery efficiency. This study demonstrates that non-lamellar structures are not compulsory for high transfection rates. The results legitimate the utilization of oleyl chains of technical grade in the synthesis of cationic transfection lipids., (©2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Objective: To identify non-high-density lipoprotein cholesterol (HDL-C) and HDL-C thresholds for pediatric nonfasting lipid screens that are more predictive of the need for lipid-lowering pharmacotherapy and estimate numbers of potentially avoidable fasting lipid panels., Study Design: In this retrospective review of children and youths aged 8-21 years presenting for preventive cardiology care, initial lipid results, recommendations for pharmacotherapy, and presence of additional cardiovascular risk factors were noted. Receiver operating characteristic curve analysis calculated threshold lipid values predicting the need for pharmacotherapy and were applied to 2 screening populations. Rates of potentially unnecessary fasting lipid panels were calculated., Results: A non-HDL-C value >156 mg/dL for children with ≥1 cardiovascular risk factors and >199 mg/dL for children without risk factors conferred 95% or greater sensitivity in predicting a recommendation for pharmacotherapy with higher specificity, positive predictive value, and negative predictive value compared with current guidelines. HDL-C was a poor predictor of pharmacotherapy. Application of the current thresholds to screening populations indicated that 38.5%-92.3% of follow-up fasting lipid panels would not result in pharmacotherapy., Conclusion: Using higher non-HDL-C and lower HDL-C thresholds could prevent unnecessary follow-up lipid panels and reduce patient anxiety, cost, and time. This could improve compliance with universal pediatric lipid screening for both health care providers and families., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: The European Federation of Clinical Chemistry and Laboratory Medicine European Biological Variation Study (EuBIVAS) has been established to deliver rigorously determined data describing biological variation (BV) of clinically important measurands. Here, EuBIVAS-based BV estimates of serum electrolytes, lipids, urea, uric acid, total protein, total bilirubin, direct bilirubin, and glucose, as well as their associated analytical performance specifications (APSs), are presented., Method: Samples were drawn from 91 healthy individuals (38 male, 53 female; age range, 21-69 years) for 10 consecutive weeks at 6 European laboratories. Samples were stored at -80 °C before duplicate analysis of all samples on an ADVIA 2400 (Siemens Healthineers). Outlier and homogeneity analyses were performed, followed by CV-ANOVA on trend-corrected data, when relevant, to determine BV estimates with CIs., Results: The within-subject BV (CV I ) estimates of all measurands, except for urea and LDL cholesterol, were lower than estimates available in an online BV database, with differences being most pronounced for HDL cholesterol, glucose, and direct bilirubin. Significant differences in CV I for men and women/women <50 years of age were evident for uric acid, triglycerides, and urea. The CV A obtained for sodium and magnesium exceeded the EuBIVAS-based APS for imprecision., Conclusions: The EuBIVAS, which is fully compliant with the recently published Biological Variation Data Critical Appraisal Checklist, has produced well-characterized, high-quality BV estimates utilizing a stringent experimental protocol. These new reference data deliver revised and more exacting APS and reference change values for commonly used clinically important measurands, thus having direct relevance to diagnostics manufacturers, service providers, clinical users, and ultimately patients., (© 2018 American Association for Clinical Chemistry.)

Safe and effective DNA delivery systems are required to enable or enhance clinical strategies and research involving gene therapy and DNA vaccinations. To address this delivery problem, a series of charge-altering releasable transporters (CARTs) with varied lipid content were prepared and evaluated for plasmid DNA (pDNA) delivery into cultured cells. These lipid-modified CART co-oligomers were synthesized in only two steps via sequential organocatalytic ring-opening polymerization of lipid-containing cyclic carbonate monomers and morpholinone monomers. Lipid variations of the CARTs substantially impacted the delivery efficiency of pDNA, with oleyl- and linoleyl-based CARTs showing enhanced performance relative to the commercial transfection agent Lipofectamine 2000 (L2000). The best-performing oleyl CART was carried forward to study stable luciferase transfection with a Sleeping Beauty ( SB) transposon system. The oleyl CART outperformed the L2000 positive control with respect to stable transfection efficiency. CART-pDNA complexes represent a new DNA delivery system for research and clinical applications.

Automatic assessment of hemoglobin (H), lipaemia (L) and icterus (I) in serum or plasma (HIL indices) is the mainstay for evaluating sample quality. We planned this study to verify whether in-house prepared internal quality control (IQC) materials may be suitable for quality assurance of HIL indices. Pools containing different values of each of the three HIL indices were prepared from routine plasma samples, divided in aliquots and frozen at -20°C. Stability of frozen materials was assessed by thawing one aliquot of each pool after different days of freezing (1, 4, 8, 15, 22 and 29), and by measuring HIL indices on baseline fresh samples and frozen-thawed aliquots with Roche Cobas c702. Five fresh liquid IQCs materials were also measured at the same time points. Intra-assay and inter-assay imprecision of HIL indices calculated with commercial IQC materials ranged between 1.1-2.0% and 1.6-3.3%, respectively. When target values of HIL indices were calculated using frozen-thawed aliquots, the inter-assay imprecision of in-house prepared materials was optimal, even better than that of commercial liquid IQCs (H-index, 0.8% versus 1.6%; L-index, 2.2% versus 2.5%; I-index, 0.8% versus 3.3%). In conclusion, in-house prepared IQC materials are cost-effective alternatives to commercial liquid IQCs for HIL quality assurance., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Efforts to harmonize lipidomic methodologies have been limited within the community. Here, we aimed to capitalize on the recent National Institute of Standards and Technology lipidomics interlaboratory comparison exercise by implementing a questionnaire that assessed current methodologies, quantitation strategies, standard operating procedures (SOPs), and quality control activities employed by the lipidomics community., Objectives: Lipidomics is a rapidly developing field with diverse applications. At present, there are no community-vetted methods to assess measurement comparability or data quality. Thus, a major impetus of this questionnaire was to profile current efforts, highlight areas of need, and establish future objectives in an effort to harmonize lipidomics workflows., Methods: The 54-question survey inquired about laboratory demographics, lipidomic methodologies and SOPs, analytical platforms, quantitation, reference materials, quality control procedures, and opinions regarding challenges existing within the community., Results: A total of 125 laboratories participated in the questionnaire. A broad overview of results highlighted a wide methodological diversity within current lipidomic workflows. The impact of this diversity on lipid measurement and quantitation is currently unknown and needs to be explored further. While some laboratories do incorporate SOPs and quality control activities, these concepts have not been fully embraced by the community. The top five perceived challenges within the lipidomics community were a lack of standardization amongst methods/protocols, lack of lipid standards, software/data handling and quantification, and over-reporting/false positives., Conclusion: The questionnaire provided an overview of current lipidomics methodologies and further promoted the need for community-accepted guidelines and protocols. The questionnaire also served as a platform to help determine and prioritize metrological issues to be investigated.

As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks for intra- and interlaboratory quality control and method validation. These analyses were performed using nonstandardized laboratory-independent workflows. The consensus locations were also compared with a previous examination of SRM 1950 by the LIPID MAPS consortium. While the central theme of the interlaboratory study was to provide values to help harmonize lipids, lipid mediators, and precursor measurements across the community, it was also initiated to stimulate a discussion regarding areas in need of improvement., (Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.)

Lipidomics is rapidly expanding because of the great facilitation of recent advances in, and novel applications of, electrospray ionization mass spectrometry techniques. The greatest demands have been for successful quantification of lipid classes, subclasses, and individual molecular species in biological samples at acceptable accuracy. This review addresses the selection of internal standards in different methods for accurate quantification of individual lipid species. The principles of quantification with electrospray ionization mass spectrometry are first discussed to recognize the essentials for quantification. The basics of different lipidomics approaches are overviewed to understand the variables that need to be considered for accurate quantification. The factors that affect accurate quantification are extensively discussed, and the solutions to resolve these factors are proposed-largely through addition of internal standards. Finally, selection of internal standards for different methods is discussed in detail to address the issues of what, how, and why related to internal standards. We believe that thorough discussion of the topics related to internal standards should aid in quantitative analysis of lipid classes, subclasses, and individual molecular species and should have big impacts on advances in lipidomics. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 36:693-714, 2017., (© 2016 Wiley Periodicals, Inc.)

Objectives: To determine reference values for laboratory tests in individuals aged 85 and older., Design: Cross-sectional cohort study., Setting: International., Participants: Long Life Family Study (LLFS) participants (N~5,000, age: range 25-110, median 67, 45% male)., Measurements: Serum biomarkers were selected based on association with aging-related diseases and included complete blood count, lipids (triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol), 25-hydroxyvitamin D2 and D3, vitamin D epi-isomer, diabetes mellitus-related biomarkers (adiponectin, insulin, insulin-like growth factor 1, glucose, glycosylated hemoglobin, soluble receptor for advanced glycation endproduct), kidney disease-related biomarkers (albumin, creatinine, cystatin), endocrine biomarkers (dehydroepiandrosterone, sex-hormone binding globulin, testosterone), markers of inflammation (interleukin 6, high-sensitivity C-reactive protein, N-terminal pro b-type natriuretic peptide), ferritin, and transferrin., Results: Of 38 measured biomarkers, 34 were significantly correlated with age. Summary statistics were generated for all biomarkers according to sex and 5-year age increments from 50 and up after excluding participants with diseases and treatments that were associated with biomarkers. A biomarker data set was also generated that will be useful for other investigators seeking to compare biomarker levels between studies., Conclusion: Levels of several biomarkers change with older age in healthy individuals. The descriptive statistics identified herein will be useful in future studies and, if replicated in additional studies, might also become useful in clinical practice. The availability of the reference data set will facilitate appropriate calibration of biomarkers measured in different laboratories., (© 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.)

Objectives: i) To assess the relationship between lipid markers and high-sensitivity C-reactive protein (hs-CRP), and high-sensitivity cardiac troponin I (hs-cTnI) in the reference population, and ii) to evaluate the impact of lipid markers and hs-CRP on the 99th percentile upper reference limit (URL) for hs-cTnI., Methods: 531 questionnaire-identified presumably healthy individuals were enrolled in a single-center, cross-sectional study. Surrogate biomarkers for diabetes, myocardial and renal dysfunction were used to refine the healthy cohort (n=408). Lipid profile, total cholesterol:high-density lipoprotein cholesterol (HDL-C) ratio, non-HDL-C, apolipoprotein AI (apoAI), apolipoprotein B (apoB), apoB:apoAI ratio, lipoprotein(a), small dense low-density lipoprotein cholesterol (LDL-C) and hs-CRP were determined., Results: Individuals with detectable vs. non-detectable hs-cTnI concentrations more often showed elevated LDL-C (60% vs. 46%; p=0.002), apoB (73% vs. 61%; p=0.008), apoB:apoAI ratio (53% vs. 40%; p=0.005) and lipoprotein(a) (15% vs. 7%; p=0.015). The apoB:apoAI ratio and to a lesser extent other lipid markers, but not hs-CRP, were positively associated with hs-cTnI concentration in univariate and multivariate analyses. Exclusion of individuals with elevated apoB:apoAI ratio or apoB, but not hs-CRP, lowered the 99th percentile URL in the healthy cohort respectively by 12.9% (6.2 vs. 5.4ng/L) and 14.5% (6.2 vs. 5.3ng/L). The corresponding reduction for both lipid biomarkers in the presumably healthy population was 24.0% (7.5 vs. 5.7ng/L)., Conclusion: Our study demonstrates that atherogenic lipid markers, particularly apoB:apoAI ratio or apoB, influence the 99th percentile URL for hs-cTnI., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The parasite Peroderma cylindricum uses its host Sardina pilchardus to meet its own needs. The parasite can have many harmful effects on its host. The present study aims at investigating the impact of the parasite on the composition of fatty acids and the quality of the lipids of the sardine. Peroderma cylindricum reduces the total lipid content of its host by about 25% and decreases the content of saturated fatty acid and polyunsaturated acid. However, it increases the amount of monounsaturated fatty acids. The parasite induced a selective diversion of some fatty acids, which are dominated by the docosahexaenoic acid. Consequently, lower n-3 fatty acid content and omega-3/omega-6 ratio were recorded in parasitized sardines. Furthermore, both atherogenic and thrombogenic indices were found to be higher than those of unparasitized specimens. Nevertheless, these alterations do not lead to an important reduction of the nutritional value of the fish.

Within recent years, ganglioside patterns have been increasingly analyzed by MS. However, internal standards for calibration are only available for gangliosides GM1, GM2, and GM3. For this reason, we prepared homologous internal standards bearing nonnatural fatty acids of the major mammalian brain gangliosides GM1, GD1a, GD1b, GT1b, and GQ1b, and of the tumor-associated gangliosides GM2 and GD2. The fatty acid moieties were incorporated after selective chemical or enzymatic deacylation of bovine brain gangliosides. For modification of the sphingoid bases, we developed a new synthetic method based on olefin cross metathesis. This method was used for the preparation of a lyso-GM1 and a lyso-GM2 standard. The total yield of this method was 8.7% for the synthesis of d17:1-lyso-GM1 from d20:1/18:0-GM1 in four steps. The title compounds are currently used as calibration substances for MS quantification and are also suitable for functional studies., (Copyright © 2014 by the American Society for Biochemistry and Molecular Biology, Inc.)

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.

The importance of lipoprotein (a)-Lp(a)-as a cardiovascular (CV) risk marker has been underscored by recent findings that CV risk is directly related to baseline Lp(a) levels, even in well-treated patients. Although there is currently little that can be done pharmacologically to lower Lp(a) levels, knowledge of its serum concentration is important in overall risk assessment. This review focuses on 1 aspect of Lp(a) that is rarely discussed directly: how to express its levels in serum. There is considerable confusion on this point, and a fuller understanding of what the concentration units mean will help improve study-to-study comparisons and thereby advance our understanding of the pathobiology of this lipoprotein particle. As discussed here, the term Lp(a) mass refers to the entire mass of the particle: lipids, proteins, and carbohydrates combined. At present, there are no commercially available assays that are completely insensitive to the variability in particle mass, which arises not only from differences in apo(a) isoform mass but also from variations in lipid mass. Because lipoprotein "particle number" (molar concentration) has been found to be superior to component-based metrics (ie, low-density lipoprotein particle vs cholesterol concentrations) for CV disease risk prediction, the development of a mass-insensitive Lp(a) assay should be a high priority., (Copyright © 2014 National Lipid Association. Published by Elsevier Inc. All rights reserved.)

Objective: Lipid profile parameters are influenced by various factors like age, ethnicity, diet, genetic and gender differences hence it is essential to establish reference range of the values of serum lipids for a given population in India. We have planned this study to evaluate the reference values of lipid profile of a North Indian population according to the guidelines of the National Cholesterol Education Program (NCEP) of the USA., Design and Methods: The present study was conducted on 2021 apparently healthy individuals of North Indian origin ranging in age from 15 to 60 years, who were selected randomly using defined criteria. Fasting samples were analyzed for total cholesterol, triglyceride, HDL-C and LDL-C. Data were analyzed for middle 95th percentile (2.5th-97.5th percentile), median and 95% confidence interval using SPSS software package version 10.0., Results: No substantial difference could be observed between male and female and vegetarian and non-vegetarian, in cholesterol, triglyceride and LDL-C levels. However HDL-C reported higher limit in female as compared to male (33-64 vs 32-58 mg/dl). Similarly upper limit of HDL-C in vegetarians were higher than non-vegetarian (value 32.8-64.92 vs 30.72-58.10mg/dl). Median value for cholesterol, triglyceride, LDL-C progressively increased in different age groups (<20, 20-40 and 41-60 years). No marked difference was observed in reference interval of these parameters in rural and urban populations., Conclusion: It can be suggested that lipid values obtained in this study can be used as the reference value, based on which clinical correlation can be made., (© 2013.)

Argon cluster ion sources for sputtering and secondary ion mass spectrometry use projectiles consisting of several hundreds of atoms, accelerated to 10-20 keV, and deposit their kinetic energy within the top few nanometers of the surface. For organic materials, the sputtering yield is high removing material to similar depth. Consequently, the exposed new surface is relatively damage free. It has thus been demonstrated on model samples that it is now really possible to perform dual beam depth profiling experiments in organic materials with this new kind of ion source. Here, this possibility has been tested directly on tissue samples, 14 μm thick rat brain sections, allowing primary ion doses much larger than the so-called static secondary ion mass spectrometry (SIMS) limit and demonstrating the possibility to enhance the sensitivity of time-of-flight (TOF)-SIMS biological imaging. However, the depth analyses have also shown some variations of the chemical composition as a function of depth, particularly for cholesterol, as well as some possible matrix effects due to the presence or absence of this compound.

Background: We aimed to establish the reference intervals for serum lipids in coastal residents of the Chinese male population., Methods: A total of 1436 subjects, aged between 19 and 86 years, were selected from the Fangchenggang Area for Male Health and Examination Survey (FAMHES). Reference intervals of serum lipids were measured by enzymatic endpoint colorimetry and information was obtained using a standard questionnaire., Results: The total nonparametric reference intervals for TC < 5.95 mmol/L (229.73 mg/dL), TG < 1.80 mmol/L (158.82 mg/dL), HDL-C > 1.90 mmol/L (73.08 mg/dL), and LDL-C < 3.37 mmol/L (130 mg/dL). High serum lipid levels were correlated with older age, higher body mass index (BMI), and more smoking, but not with alcohol consumption., Conclusions: The established reference intervals of serum lipids for coastal Chinese male residents would be helpful for assessing risk of cardiovascular disease. We recommend establishing population-based reference intervals for serum lipids in clinical laboratories.

The Lipid Formulation Classification System Consortium is an industry-academia collaboration, established to develop standardized in vitro methods for the assessment of lipid-based formulations (LBFs). In this first publication, baseline conditions for the conduct of digestion tests are suggested and a series of eight model LBFs are described to probe test performance across different formulation types. Digestion experiments were performed in vitro using a pH-stat apparatus and danazol employed as a model poorly water-soluble drug. LBF digestion (rate and extent) and drug solubilization patterns on digestion were examined. To evaluate cross-site reproducibility, experiments were conducted at two sites and highly consistent results were obtained. In a further refinement, bench-top centrifugation was explored as a higher throughput approach to separation of the products of digestion (and compared with ultracentrifugation), and conditions under which this method was acceptable were defined. Drug solubilization was highly dependent on LBF composition, but poorly correlated with simple performance indicators such as dispersion efficiency, confirming the utility of the digestion model as a means of formulation differentiation., (Copyright © 2012 Wiley Periodicals, Inc.)

Introduction: By improving lipid standardization, the Centers for Disease Control and Prevention's (CDC's) Lipid Standardization Program and Cholesterol Reference Method Laboratory Network have contributed to the marked reduction in heart disease deaths since 1980. The objective of this study was to estimate the benefits (ie, the value of reductions in heart disease deaths) and costs attributable to these lipid standardization programs., Methods: We developed a logic model that shows how the inputs and activities of the lipid standardization programs produce short- and medium-term outcomes that in turn lead to improvements in rates of cardiovascular disease and death. To calculate improvements in long-term outcomes, we applied previous estimates of the change in heart disease deaths between 1980 and 2000 that was attributable to statin treatment and to the reduction in total cholesterol during the period. Experts estimated the share of cholesterol reduction that could be attributed to lipid standardization. We applied alternative assumptions about the value of a life-year saved to estimate the value of life-years saved attributable to the programs., Results: Assuming that 5% of the cholesterol-related benefits were attributable to the programs and a $113,000 value per life-year, the annual benefit attributable to the programs was $7.6 billion. With more conservative assumptions (0.5% of cholesterol-related benefits attributable to the programs and a $50,000 value per life-year), the benefit attributable to the programs was $338 million. In 2007, the CDC lipid standardization programs cost $1.7 million., Conclusion: Our estimates suggest that the benefits of CDC's lipid standardization programs greatly exceed their costs.

Microalgae are considered one of the best candidates for biofuel production due to their high content in neutral lipids, therefore, an accurate quantification of these lipids in microalgae is fundamental for the identification of the better candidates as biodiesel source. Nile red is a fluorescent dye widely employed for the quantification of neutral lipids in microalgae. Usually, the fluorescence intensity of the stained samples is correlated to the neutral lipid content determined with standard methods, in order to draw a standard curve and deduce the neutral lipids concentration of the unknown samples positioning their fluorescence intensity values on the curve. Standard methods used for the neutral lipids determination are laborious and often implying solvent extraction and/or other transformation (i.e. saponification or transesterification) of the sample. These methods are also time consuming and may give rise to an underestimation of the lipid content due to variable extraction yields. The approach described in this paper combines the standard addition method and the fluorometric staining using Nile red, avoiding the association of traditional neutral lipids quantification methods to the fluorometric determination. After optimization of instrument parameters and staining conditions, a linear correlation between the fluorescence intensity of each sample stained with the Nile red and its neutral lipids content deduced with the standard addition method was identified. The obtained curve allowed the direct determination of neutral lipids content maintaining a linearity range from 0.12 to 12 μg of neutral lipids per ml of sample, without need of pre-concentration. This curve was then used in the quantification of the neutral lipids content in culture of Skeletonema marinoi (Bacillariophyceae) at different days from the inoculum. This method was also successfully applied on Chaetoceros socialis (Bacillariophyceae) and Alexandrium minutum (Dinophyceae)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

A series of amphiphilic ion pairs of erythromycin (ERY) with lipoamino acids (LAAs) were produced. The ion pairs were prepared by evaporation of a water/ethanol co-solution of the drug and LAA bearing an alkyl side chain of 10-16 carbon atoms. For the sake of comparison, equimolar physical mixtures were prepared by triturating ERY and the LAA in the absence of any solvent. FTIR spectroscopy confirmed the structure of ion pairs, while differential scanning calorimetry and powder X-ray diffractometry were used to assess the formation of new saline species. The solubility pattern of the coevaporates in different aqueous and organic solvents confirmed their amphiphilic properties. ERY-LAA ion pairs were submitted to an in vitro microbiological assay against different bacterial strains, both susceptible and resistant to macrolides. The presence of the LAA moiety was shown not altering the antibacterial spectrum of activity of the drug. These results can be the basis for a further evaluation of ERY-LAA ion pairs as a mean to improve the penetration of the drug inside bacterial cells and to optimize the loading of ERY in lipid-based nanocarriers.

Background: The present study was designed to explore the reference values of serum lipids in children in Beijing., Methods: A total of 1071 healthy children from Beijing between 3 and 18 years of age were enrolled and divided into four groups: A, 3-5-year-old group; B, 6-9-year-old group; C, 10-14-year-old group; and D, 15-18-year-old group. Blood samples were obtained from the cubital veins of the participants under a fasting condition. A Hitachi 7600 Automatic Biochemistry Analyzer was used to determine the serum levels. The cut-off points of reference values were the 75th and 95th percentiles for total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) while the 25th and 5th percentiles were used for high-density lipoprotein cholesterol (HDL-C) concentrations., Results: The highest 95th percentiles of TC among the four groups were 5.34 mmol/L for boys and 5.11 mmol/L for girls. Compared with those of boys, female TG levels were obviously higher in the 10-14-year-old group (P < 0.05) and HDL-C levels were significantly higher in the 15-18-year-old group (P < 0.05). The serum TC, HDL-C, and LDL-C all peaked during the 6-9-year-old period and then declined during the adolescent stage. Also, the serum TG continuously increased with a relative plateau during the 6-14-year-old period. Obese and overweight children had higher TG and LDL-C levels but lower HDL-C levels., Conclusion: This study showed a picture of the serum lipids distribution in Chinese children and found that their TC levels were lower than those of children in Japan, Iran, and France, but were higher than those of Italian children.

A general and easily accessible method for the extraction followed by the simultaneous separation and quantitative determination of triacylglycerols, diacylglycerols, monoacylglycerols and free fatty acids has been improved and optimized based on existing protocols using liquid-phase extraction and thin-layer chromatography coupled to flame ionization detection (TLC/FID Iatroscan). After lipid extraction in the presence of a suitable new synthetic internal standard, namely CholE1, a single elution step using n-heptane/diethyl ether/formic acid (55:45:1, v/v/v) was applied. This method was validated in line with international bioanalytical method validation guidelines using two different matrix systems: purified water and human gastro-intestinal fluid. Overall, the assay was found to have high levels of precision with coefficients of variation ranging from 1.48% to 11.0% and accuracy ranging from -13.3% to +5.79% RE. The confidence limits of the lipid mean recovery rates varied between 89.9% and 104%. This method is therefore highly suitable for quantifying the lipolysis products generated in vitro during the hydrolysis of various fats and oils by digestive lipases, as well as those collected from the gastro-intestinal tract in the course of human clinical studies on lipid digestion.

Lipid-based Delivery Systems (LDS) has been the focus of potential strategies in drug delivery for several years. A great deal of work has been invested on how to exploit their biocompatible and biodegradable nature, in combination with their nanosize range in a profitable way in the field of nanomedicines. A number of drugs loaded in LDS have been already tested in vivo successfully. However, in vivo behaviour of nanosized materials differs from their bulk counterparts (and also change drug properties), mainly depending on the particular LDS physicochemical characteristics. These may have huge impact on the toxicity of the system, despite the physiological nature of the lipid materials. This note on the regulatory concerns and toxicity assessment in LDS suggests that current knowledge of public and scientific communities is lacking, requiring intensive research and policy measures to provide a deep understanding on toxicological risks.

Background: Targets for cholesterol reduction are part of the Quality Outcomes Framework and general practitioners have to meet these targets to fulfil their remuneration package. By contrast, there are no targets for the accuracy of cholesterol or other lipid measurements and no recent surveys on performance of these assays. We have assessed the performance of lipid measurement of the available methods in the UK., Methods: Serum samples collected from individual donors attending the national blood service were distributed after values were obtained from a secondary reference laboratory. Samples were sent to participant laboratories to assess different methods' analytical performance on single donation specimens, on routine external quality assessment pooled specimens, on specimens subjected to a range of freeze-thaw cycles and on frozen-stored specimens., Results: Differences in measured cholesterol were found that were method-dependent and related to triglyceride content. HDL-cholesterol (HDL-C) showed significant positive bias in all assays. Individual donor specimens showed no significant changes with differing numbers of freeze-thaw cycles. Pooled serum was stable for up to six months., Conclusions: Most cholesterol measurements are accurate but some methods are affected by triglyceride interference. HDL-C methods show significant positive bias. Although there are potential matrix effects introduced as a result of specimen preparation, additional work is needed to show if these effects are present in fresh patient samples.

Electrical impedance gives multivariate complex number data as results. Two examples of multivariate electrical impedance data measured on lipid monolayers in different solutions give rise to matrices (16x50 and 38x50) of complex numbers. Multivariate data analysis by principal component analysis (PCA) or singular value decomposition (SVD) can be used for complex data and the necessary equations are given. The scores and loadings obtained are vectors of complex numbers. It is shown that the complex number PCA and SVD are better at concentrating information in a few components than the naïve juxtaposition method and that Argand diagrams can replace score and loading plots. Different concentrations of Magainin and Gramicidin A give different responses and also the role of the electrolyte medium can be studied. An interaction of Gramicidin A in the solution with the monolayer over time can be observed.

Qualification, preparation, and use of lipid compounds as analytical reference standards are daunting endeavors. The sheer vastness of the number of lipid compounds present in biological samples make it impossible to directly standardize each entity. Available lipid compounds chosen for preparation as standards are difficult to maintain as pure entities of stable concentration due to their physical and chemical interactions. The lipid chemist must understand these constraints for each chosen molecule to construct a standard material, which provides accurate measurement for a practical length of time. We provide methods and guidelines to aid the chemist in these endeavors. These aids include analytical methods for preparation and handling techniques, qualification of candidate materials, packaging, storage, and, finally, stability testing of working standard materials. All information will be provided under the purview of standardization of lipid analysis by mass spectrometry.

The corona discharge used to generate positive and negative ions under conventional atmospheric pressure chemical ionization (APCI) conditions also provides a source of low-energy gas-phase electrons. This is thought to occur by displacement of electrons from the nitrogen sheath gas. Therefore, suitable analytes can undergo electron capture in the gas phase in a manner similar to that observed for gas chromatography/electron capture negative chemical ionization/mass spectrometry (MS). This technique, which has been named electron-capture APCI (ECAPCI)/MS, mass spectrometry provides an increase in sensitivity of two orders of magnitude when compared with conventional APCI methodology. It is a simple procedure to tag arachidonic acid- and linoleic acid-derived oxidized lipids with an electron-capturing group such as the pentafluorobenzyl (PFB) moiety before analysis. PFB derivatives have previously been used as electron-capturing derivatives because they undergo dissociative electron capture in the gas phase to generate negative ions through the loss of a PFB radical. A similar process occurs under ECAPCI conditions. By monitoring the negative ions that are formed, it is possible to obtain extremely high sensitivity for PFB derivatives of oxidized lipids derived from arachidonic and linoleic acid. A combination of stable isotope dilution methodology and chiral liquid chromatography-ECAPCI/MS makes it possible to resolve and quantify complex mixtures of regioisomeric and enantiomeric oxidized lipids.

Purpose of Review: The aim of this article is to describe recent advances in our understanding of lifetime risks for cardiovascular disease and their implications for lipid guidelines., Recent Findings: Recent studies have indicated that, among younger and middle-aged adults, there is a large subset with low 10-year risk but high lifetime risk for cardiovascular disease. Individuals with high lifetime risks can be identified on the basis of single adverse risk factors or on the basis of overall risk factor burden. For example, using the ATP-III online risk estimator, a 45-year-old obese, nonsmoking, nondiabetic man with total cholesterol of 200 mg/dl, HDL-cholesterol of 40 mg/dl, and untreated systolic blood pressure of 135 mmHg has an estimated 10-year risk for hard coronary heart disease of 3%. In contrast, recent data indicate that his predicted remaining lifetime risk for cardiovascular disease is 50% and his predicted median survival is over 10 years shorter than a man at the same age with optimal risk factors., Summary: Lifetime risk estimation for cardiovascular disease may be an important adjunct to short-term (10-year) risk estimation that may help identify more treatment-eligible individuals at risk for cardiovascular disease, improve risk communication, motivate changes in lifestyle and behaviors, and promote adherence to therapy.

Objectives: Lipid biomarkers are integral in the assessment of dyslipidemia and cardiovascular risk, conditions that have become increasingly prevalent in pediatric populations. A comprehensive set of pediatric reference intervals for traditional or recently established lipid analytes is not currently available., Design and Methods: 525 outpatient samples from a pediatric population were categorized into five age groups ranging from 0 to 20 years of age. Groups were further partitioned by gender. Serum or plasma samples were analyzed on the VITROS 5,1 FS Chemistry System for cholesterol and triglycerides by dry-film methods, direct HDL-C and LDL-C by selective detergent elimination, and apolipoproteins AI and B by immunoturbidimetry. Reference intervals were established by non-parametric methods at the 2.5th and 97.5th percentiles., Results: Lipid levels show age- and gender-related differences, particularly during the first year of life and in young adults following puberty. Concentrations of total cholesterol, LDL-C, and apo B were lowest in the 12 months after birth and remained relatively constant throughout childhood, but decreased for males in early adulthood. Triglyceride levels increased gradually throughout childhood and adolescence, and along with cholesterol, the upper limits of these intervals exceeded the recommended concentrations of lipid levels in children. For HDL-C and apo AI, no age- or sex-related differences were found until after puberty when values for males decreased slightly., Conclusions: Our current reference intervals in children and adolescents provide an important update for lipid markers and suggest earlier incidence of hypercholesterolemia when compared to previous ranges. Increased profiling of lipids is anticipated, and these will aid in the early assessment of cardiovascular risk in pediatric populations.

We quantified the rates of incorporation of alpha-linolenic acid (alpha-LNA; 18:3n-3) into "stable" lipids (triacylglycerol, phospholipid, cholesteryl ester) and the rate of conversion of alpha-LNA to docosahexaenoic acid (DHA; 22: 6n-3) in the liver of awake male rats on a high-DHA-containing diet after a 5-min intravenous infusion of [1-(14)C]alpha-LNA. At 5 min, 72.7% of liver radioactivity (excluding unesterified fatty acid radioactivity) was in stable lipids, with the remainder in the aqueous compartment. Using our measured specific activity of liver alpha-LNA-CoA, in the form of the dilution coefficient lambda(alpha-LNA-CoA), we calculated incorporation rates of unesterified alpha-LNA into liver triacylglycerol, phospholipid, and cholesteryl ester as 2,401, 749, and 9.6 nmol/s/g x 10(-4), respectively, corresponding to turnover rates of 3.2, 8.7, and 2.9%/min and half-lives of 8-24 min. A lower limit for the DHA synthesis rate from alpha-LNA equaled 15.8 nmol/s/g x 10(-4) (0.5% of the net in corporation rate). Thus, in rats on a high-DHA-containing diet, rates of beta-oxidation and esterification of alpha-LNA into stable liver lipids are high, whereas its conversion to DHA is comparatively low and insufficient to supply significant DHA to the brain. High incorporation and turnover rates likely reflect a high secretion rate by liver of stable lipids within very low density lipoproteins.

The aim of this study was to design stable parenteral pharmaceutical final products containing 25 mg and 50 mg ES-285.HCl per dosage unit for use in phase I clinical trials. ES-285.HCl drug substance was fully characterised and showed very slight solubility in water. The development of the pharmaceutical product, containing 2-hydroxypropyl-beta-cyclodextrin, is discussed in view of formulation optimisation and manufacture. The developed freeze-dried products were found stable for at least 6 months at an accelerated storage condition of 25 +/- 2 degrees C/60 +/- 5% relative humidity and for at least 12 months at the designated long term storage condition of 5 +/- 3 degrees C, in the dark. Phase I trials using ES-285.HCl 25 mg/vial and 50 mg/vial final products are currently ongoing.

The role of lipids, lipoproteins and lipoprotein(a) [Lp(a)] in coronary artery disease (CAD) is known but the role of major apolipoproteins (apos) other than apo A-I and apo B remains unclear. In this study, using immunoturbidimetry we have estimated serum levels of total cholesterol, HDL-C, LDL-C, triglyceride, LDL-apoB and all major apos; A-I, A-II, B, C-II, C-III and E, in 751 healthy Indian subjects (470 men and 281 women, age 25-65 years), determined their percentiles, and established reference intervals. The effects of age, smoking and alcohol on all these analytes were also evaluated. This is the first study to provide reference intervals for all apos, in both sexes from a general population. The percentiles and the reference intervals have clinical relevance and will be useful in assessing the risk of CAD in patients with hyperlipidemia and other diseases.

In this study we demonstrated the combination of MALDI-TOF MS and TLC as a fast and powerful tool to investigate the phospholipid (PL) composition of organic extracts of bull spermatozoa. Since phosphatidylcholine (PC) is the dominant PL species, an adequate resolution of MALDI-TOF spectra for sphingomyelin (SM) or phosphatidylethanolamine (PE) was achieved only after previous PL separation by TLC. We found a poor diversity especially for PE and PC, mainly containing ether-linked fatty acids which were 1-palmityl-2-docosahexaenoyl-PL and the corresponding alkenyl-acyl compound (plasmalogen) 1-palmitenyl-2-docosahexaenoyl-PL. For PC, both lipids were quantified after phospholipase A2 digestion to represent 44.2 and 37.2%, respectively, of the total PC. In contrast, the diacyl-PC content of bull spermatozoa was comparatively low (18.6% of total PC). In the presence of trifluoroacetic acid (TFA), which is routinely added to the MALDI-TOF matrix to improve the signal to noise ratio, a high lysophospholipid (LPL) content was detected in the PL extracts of bull spermatozoa, whereas TLC did not reveal significant amounts of LPL. The TFA mediated hydrolysis of the acid-labile alkenyl-acyl PL to the corresponding LPL was shown to cause this discrepancy. This assumption was verified by analysing the PL composition by MALDI-TOF MS before and after (i) digestion of sperm cell lipids with phospholipase A2 and (ii) exposition of spermatozoa to HCl fumes. We conclude that the analysis of samples containing alkenyl-acyl-PL by MALDI-TOF has to be performed with great caution.

Background: The Dutch project "Calibration 2000" aims at harmonization of laboratory results via calibration by development of matrix-based secondary reference materials. We considered the selection, preparation, and characterization of 34 potential reference materials (PRMs)., Methods: Sixteen PRMs were prepared either strictly according to the NCCLS C37-A protocol or in a less stringent and more convenient way. In addition, 18 commercial, so-called human serum-based calibrators or controls were purchased and tested. Lipoprotein integrity was evaluated by examining the physicochemical characteristics of the materials. Commutability of the PRMs was assessed in 86 Dutch clinical laboratories, using a multicenter split-patient-sample between-field-method (twin-study) design. Normalized residuals of the PRMs with respect to the patient regression lines were calculated; in addition, the extra contribution of each PRM to the total measurement uncertainty (CV(Netto)) was calculated. On the basis of these results, the most native PRM was selected to investigate its potential to reduce interlaboratory variation and to improve lipid and apolipoprotein standardization., Results: In general, only the NCCLS C37-A-type materials displayed normalized residuals below the decision limit for commutability and had small CV(Netto) values ranging between 0 and 3.8%. This contrasts with the findings in regularly pooled frozen sera and lyophilized cryoprotected PRMs. In two subsequent external quality assessment surveys, the NCCLS type C37-A materials contributed to reducing the intermethod lipid and (apo)lipoprotein variation to approximately 2-4%., Conclusions: NCCLS C37-A materials have a strong potential as secondary reference materials, not only for cholesterol but also for HDL-cholesterol, LDL-cholesterol, triglyceride, and apolipoprotein measurements.

Fermentation and acidification have been shown to preserve the protein quality of ground poultry coproducts, but the effects of these processes on their lipid stability are unknown, especially in the presence of an antioxidant. To evaluate the effects of these treatments on lipid quality, ground poultry mortality carcasses, with and without an addition of 500 ppm ethoxyquin, were stabilized for 14 and 45 d by lactic acid fermentation or acidification with 2.76, 5.07, 7.35, or 9.65% feed-grade H3PO4. Ethoxyquin treatment significantly (P < 0.001) improved the oxidative stability of lipids from all storage treatments. However, the addition of ethoxyquin increased (P < 0.001) the levels of volatile N (VN) from 2.51 to 3.18% in products stored for 45 d and resulted in an increase (P < 0.001) in free fatty acids in all ensiled products. Ethoxyquin addition had no effect (P > 0.120) on the fatty acid profile of products stored for 14 d but significantly increased (P < 0.001) the levels of stearic (C18:0) and arachidonic acids (C20:4) in products stored for 45 d. In this experiment, the addition of ethoxyquin to preservation systems for the short-term storage of poultry mortality carcasses improved the lipid quality of the ground material without compromising the protein quality or affecting proximate analysis parameters. However, the increased oxidative stability of mortality silage materials that contain ethoxyquin may contribute to enhanced microbial or enzymatic activities that result in proteolytic or lypolytic breakdown products following longer periods of storage.

Normal human epidermal keratinocytes were isolated and cultivated in serum-free medium. The expression of the integrin subunits alpha6 and beta1 indicated that a high number of keratinocytes from the stem cell system was present. These cells were transfected with complexes made of different cationic lipids and marker genes. Effectene showed a 20-fold higher transfection efficiency, compared to Lipofectin and Lipofectamine, and a similar low toxicity. The transfection protocol was optimised. A DNA/lipid ratio of 0.133 showed the highest transfection efficiency. Keratinocytes expressed the marker gene luciferase for 20 days. The maximum expression occurred after 3-4 days, where individual patches of fluorescent keratinocytes were detected. Transfected keratinocytes, cultivated at the air-liquid interface, expressed the marker gene beta-galactosidase for at least 7 weeks.

Practice guidelines and clinical pathways are increasingly being used as tools to enhance the quality of health care services and to manage costs better. This article reviews the role of guidelines and clinical pathways in health care as defined within the broader concept of practice policies. The factors that increase the effectiveness of practice policies are examined. These include the origin of development, dissemination technique, and implementation strategy. Policies that are internally developed and implemented with concurrent reminder systems are the most effective. Clinical pathways fit these criteria and are therefore highly effective policy types. The roles that pharmacists within health systems can undertake in policy development are described. These include writing the policy document, providing expert review, providing education, and most important, facilitating the desired outcomes by implementing pharmacy services that promote compliance with the guidelines. Examples of pharmacy-based guideline and pathway implementation from the Henry Ford Health System are described for inpatient anticoagulation, outpatient preferred drug formulary policy, and outpatient lipid therapy management.

Objective: To implement a quality control program for the standardization and harmonization of lipid and lipoprotein analyses as performed at two core laboratories (St. Paul's Hospital, UBC [Vancouver], and NPHI [Helsinki]) for the Diabetes Atherosclerosis Intervention Study (DAIS)., Design and Methods: A DAISSOFT computer program was designed to minimize the occurrence of data and sample management errors during the course of the study. Fresh human serum was used for the provision of an accuracy based external quality control program that monitored the analytical performance of lipid testing at these two laboratories. A separate program was designed for monitoring hemoglobin A1c (HbA1c). At the outset of the study, allowable total error goals were established for each analyte. Ongoing performance was monitored using bimonthly blinded challenges of fresh human serum. The two EQA programs routinely monitored the analysis of total cholesterol, calculated LDL-cholesterol, HDL-cholesterol, net triglycerides, apoprotein A-1, apoprotein B, and HbA1c., Results: The EQA precision and accuracy data for the measurement of total cholesterol at the two core laboratories over the last 5 years indicated both laboratories operated with good precision, approximately 1% CV over the time period. The accuracy at both laboratories was similar initially. Part way through the study, the accuracy of the cholesterol method at NHPI tended to drift upward with an operating positive bias (+3%) relative to the Abell Kendall reference method. Triglyceride measurements were the most problematic for the study. By EQA cycle 8, the accuracy of the method at UBC had stabilized and was meeting the accuracy goals of the study. NPHI's method was negatively biased relative to the accuracy base of the DAIS study. In spite of recalibrating their method, NPHI found it difficult to maintain consistent accuracy for the measurement of triglycerides during the study. Both laboratories operated their HDL methods with excellent precision. Accuracy at NHPI was well maintained over the course of the study whereas the accuracy of HDL measurements at UBC was more problematic. There was an inconsistent variation in the accuracy of apoprotein A-1 measurements at both laboratories. In most cases, the bias would be corrected by the time of the next EQA challenge. In the case of apo B, one laboratory was standardized to the CDC while the other laboratory was standardized to IFCC/WHO. The discrepancy between these two accuracy bases was >20%. Recalibration to a common accuracy base rectified the problem. Only minor problems were encountered with the precision and accuracy of the DIAMAT assay for hemoglobin A-1c. The two DAIS core laboratories consistently operated within the 9% total error goals of the study for HbA1c., Conclusions: Through the use of this program, the two DAIS core laboratories were able to maintain their lipid analyses within the limits of allowable total error that had been established for the study.

Background: The recognition of dyslipidemias as a major modifiable risk factor for atherosclerosis and coronary heart disease underlines the need to obtain precise and accurate assay results of plasma lipids. Today the use of automatic laboratory methods and of internal quality control favours the precision of the results but does not guarantee accuracy. The efficiency of a laboratory can be ensured by a standardization programme, systematically monitoring precision and accuracy by means of independent internal and external quality control, international reference standards (e.g. those of CDC-NHLBI and WHO) and protocols to identify and reduce the errors due to biological variability and pre-analytical factors. After the foundation of the Regional Project for Prevention of Cardiovascular Diseases in Friuli-Venezia Giulia, a lipid standardization programme was set-up, covering the 20 chemico-clinical laboratories of the Region. The programme was directed by the International WHO-MONICA-Lipid Reference Centres of Prague-Udine., Methods: During the years 1993-1994, three sets of lyophilized human serum samples were dispatched to each laboratory for the blind evaluation of total cholesterol, triglycerides and HDL-cholesterol. The samples were obtained by the combination of three serum pools at least at different lipid concentration. The first set included 20 samples to be tested in 5 weeks, the second set included 30 samples to be tested in 8 weeks and the third set included 21 samples to be tested in 9 weeks. The assay results were sent to the Prague-Udine WHO-MONICA Centres where they were computerized and evaluated, particularly considering precision for each set, estimated by the variation coefficient (i.e. standard deviation/mean value of the measurements per cent) and accuracy (the bias was computed as mean of the measurement minus the reference value/reference value per cent)., Results: In the three assay series for total cholesterol, almost all the laboratories showed the variation co-efficient (precision) to be less than the WHO-MONICA limit of 3.7% (for a cholesterol level of 250 mg) (Tab. II) and in 8 cases out of 20, less than the CDC limit of 3%; the accuracy bias was less than the WHO-MONICA limit of 5% in 17 laboratories out of 20 and less than the CDC limit of 3% in 11 cases out of 20. For the HDL-cholesterol standardization programme the reference values were based upon the phosphotungstate method. However, the pools were also controlled by the other precipitation methods used in the 20 participating laboratories: 11 laboratories worked within the WHO-MONICA limits of precision and accuracy (respectively 6.5% and 7.5%) in at least two of the three sets. Concerning triglycerides, the regional laboratories showed a greater variability and, though most of the variation coefficients were within the WHO-MONICA limit of 5%, half of the accuracy biases were greater than the limit of 10%. The bias of the measurement average of all the laboratories was excellent for total and HDL-cholesterol, not quite good but acceptable for triglycerides. Laboratory performance improved progressively from the first to the last set, on more than one occasion., Conclusions: The lipid standardization experience carried out in the framework of the Regional Project for Prevention of Cardiovascular Disease demonstrates that it is possible to set up a wide and co-ordinated collaboration with laboratories of an entire region with positive and improving results. For this global quality control system, the resource allocated is limited but widely rewarded by the community benefits in terms of assay reliability and savings at medical care level, basic research and population studies.

The stability of the coated lipid fraction of a standard weaning diet was verified by comparing growth and fatty acid incorporation for European sea bass fed diets with an identical formulation but prepared either by extrusion/coating or extrusion only. For each type of experimental diet, a (n-3) HUFA level of 1 and 2.5% of the dry diet was evaluated. European sea bass Dicentrarchus labrax L. were weaned and consequently reared for 23 days on the experimental diets in a recirculation system. A commercial weaning diet served as a control. Final individual dry weight of sea bass larvae weaned and ongrown for a total period of 30 days on the various diets did not differ significantly. The (n-3) HUFA content of the fish tissue was a reflection of the dietary (n-3) HUFA requirements of European sea bass during and immediately after weaning did not exceed 1% of the dry diet. The combined technique of cooking-extrusion of a basal diet followed by coating of a lipid emulsion proved to be a valid technique to prepare diets for studying quantitative fatty acid requirements of weaning and first ongrowing stages of marine fish. A standard diet with open formulation is proposed.

The applicability of a novel enzymatic assay for quantifying skin surface lipids was investigated experimentally. The standard curves for the assays of glycerol esters, free fatty acids, and cholesterol and its esters were linear over a wide range of lipid concentrations, which ensures the accuracy of measurements. The assay system also showed good simultaneous reproducibility. There were significant positive correlations (P < 0.001) between the quantities of glycerol esters, free fatty acids, and cholesterol and its esters sampled from the skin surface of women when measured by the enzymatic assay compared with the gas chromatographic method. The enzymatic assay was applied to studies of the relationships between age, acne and menstrual cycle, and skin surface lipids in women. The quantities of glycerol esters and free fatty acids reached peaks in females in their twenties and thirties. Increased quantities of glycerol esters, free fatty acids, and cholesterol and its esters were observed in women with acne compared with women without acne. Among the women with acne, those in the premenstrual phase of the menstrual cycle showed increased levels of glycerol esters, free fatty acids, and cholesterol and its esters compared with those in the menstrual phase. The results suggest that the enzymatic method is a satisfactory new technique for the quantification of skin surface lipids.

As part of a longitudinal study--the Kristianstad Survey--we measured plasma cholesterol, HDL- and LDL-cholesterol, triglycerides and lipoprotein (a) in a reference group consisting of 203 men and women aged 20-80, randomly sampled from a well-defined area in the southernmost part of Sweden. The selection of reference individuals and the collection of specimens for assay of the constituents were performed in accordance with current recommendations. The results were subjected to statistical analyses both with and without application of exclusion criteria. Application of the theoretical exclusion criteria resulted in the exclusion of 22% of the participants; however, this procedure had a remarkably weak impact on the results: the mean values and the standard deviations were almost unaltered. The mean (standard deviation) for cholesterol was 5.9 (1.3) mmol l-1, for HDL-C 1.1 (0.3) mmol l-1, and for LDL-C 4.3 (1.2) mmol l-1. Women had higher values than men. Plasma triglycerides were positively skewed; their median and Q3-Q1-values were 1.0 and 0.5 mmol l-1 respectively, men higher than women. There was an increase with age for cholesterol and LDL-C in both sexes and for triglycerides in women. The steepest increase of cholesterol values with age in women coincided with menopause, which have a more clear-cut separation between high and low cholesterol values than did any age limit.

Milk fat has been identified as a hypercholesterolemic fat because it contains cholesterol and is primarily saturated. However, different types of dietary saturated fats do not have equivalent effects on plasma cholesterol levels relevant to ingestion of polyunsaturated fats. Research suggests that the hypercholesterolemic effect of saturated fats in human diets is largely due to 12, 14, and 16 carbon chain length fatty acids. Evidence also suggests that stearic acid (C18:0) is as effective as oleic acid (C18:ln-9) in lowering plasma cholesterol levels when either replaces palmitic acid (C16:0) in the diet of men. Milk fat has a unique fatty acid profile with approximately 10% short- and medium-chain length saturated fatty acids (less than 12 carbons) and 35% of total fatty acids from stearic and oleic acids. The contribution of milk products to fat and cholesterol intake in the typical American diet is less than that provided by other animal products. This paper will review the recommendations of the National Cholesterol Education Program, the effects of milk fat ingestion on blood cholesterol, and the rationale and feasibility of three approaches to modifying the lipid composition of milk fat.