Quantitative Lipidomic Analysis of Serum Phospholipids Reveals Dissociable Markers of Alzheimer's Disease and Subcortical Cerebrovascular Disease.

Background: Circulating phospholipid species have been shown to predict Alzheimer's disease (AD) prognosis but the link between phospholipid disturbances and subcortical small vessel cerebrovascular disease (CeVD) common in AD patients is not known.

Objective: Mass-spectrometry lipidomics was applied to quantify serum diacyl, alkenyl (ether), alkyl, and lyso phospholipid species in individuals with extensive CeVD (n = 29), AD with minimal CeVD (n = 16), and AD with extensive CeVD (n = 14), and compared them to age-matched controls (n = 27). Memory was assessed using the California Verbal Learning Test.

A Case of Clinical Confusion Due to Erroneous M-protein Quantifications: To Splice or Skim?

An M-protein identified on electrophoresis is conventionally quantified by integrating the M-spike from baseline (PD), invariably including some irrelevant/background proteins. The use of an alternative approach that skims the M-spike tangentially thereby excluding the background proteins (TS), however, has been scanty. We report herein a case in which PD overestimated the M-proteins inconsistently, leading to confusion over relapse in a multiple myeloma patient.

Lot verification practices in Ontario clinical chemistry laboratories - Results of a patterns-of-practice survey.

Objectives: Verifying new reagent or calibrator lots is crucial for maintaining consistent test performance. The Institute for Quality Management in Healthcare (IQMH) conducted a patterns-of-practice survey and follow-up case study to collect information on lot verification practices in Ontario.

Methods: The survey had 17 multiple-choice questions and was distributed to 183 licensed laboratories.

Value of liver biopsy in anorexia nervosa-related transaminitis: A case study and literature review.

Anorexia nervosa (AN) is a complex eating disorder that affects multiple organs. 60% of patients have liver injury with transaminitis. The mechanism of liver injury in AN remains unclear.

Improved anaerobic co-digestion of food waste and domestic wastewater by copper supplementation - Microbial community change and enhanced effluent quality.

Anaerobic co-digesters are biorefineries for energy recovery from food waste and domestic wastewater via methane production. Nonetheless, the performance of this technology was not always satisfied due to the long chain fatty acids (LCFAs) generation from food waste. Micronutrient supplementation is an effective strategy that could be applied during the anaerobic (co-)digestion to further enhance the digestion efficiency while treating food waste.

Soluble Epoxide Hydrolase-Derived Linoleic Acid Oxylipins in Serum Are Associated with Periventricular White Matter Hyperintensities and Vascular Cognitive Impairment.

White matter hyperintensities (WMH) are presumed to indicate subcortical ischemic vascular disease but their underlying pathobiology remains incompletely understood. The soluble epoxide hydrolase (sEH) enzyme converts anti-inflammatory and vasoactive cytochrome p450-derived polyunsaturated fatty acid epoxides into their less active corresponding diol species. Under the hypothesis that the activity of sEH might be associated with subcortical ischemic vascular disease and vascular cognitive impairment, this study aimed to compare the relative abundance of sEH substrates and products in peripheral blood between patients with extensive WMH (discovered due to transient ischemic attack; n = 29) and healthy elderly with minimal WMH (n = 25).

Diagnostic implications of enumerating and reporting beta fraction(s) for the detection of beta-migrating monoclonal immunoglobulins in serum protein electrophoresis.

Background: Modern serum protein electrophoresis (SPE) resolves serum proteins in 6 major fractions, splitting beta (B) into beta1 (B1) and beta2 (B2). Beta-migrating monoclonal immunoglobulins (B-MC) commonly integrate into normal-looking peak shape(s) but may increase the fraction value, forming the basis for reflex testing. The objectives of this study were (1) to ascertain the value of beta fraction(s) reporting, and (2) to compare the diagnostic performance between different beta-flagging approaches, particularly ↑B versus ↑B1 and/or ↑B2.

Candidate recommendations for protein electrophoresis reporting from the Canadian Society of Clinical Chemists Monoclonal Gammopathy Working Group.

Protein electrophoresis is commonly used as an aid in the diagnosis of monoclonal gammopathies and is performed in many laboratories in Canada and throughout the world. However, unlike many other diagnostic tests, there is limited guidance for standardization and neither guidance nor specific recommendations for clinical reporting of serum (SPE) or urine (UPE) protein electrophoresis and immunotyping available in the literature. Therefore, a Canadian effort was undertaken to recommend standards that cover all aspects of clinical reporting with an ultimate goal towards reporting standardization.

A Challenging Diagnosis of IgG4-Related Disease When Understanding Limitations of Laboratory Testing Was Pivotal.

A 76-year-old man was incidentally found on a CT scan to have lymphadenopathy and bilateral kidney enlargement suggestive of infiltrative renal disease. He was largely asymptomatic but had bilateral salivary and lacrimal gland enlargement. A grossly elevated serum IgG (>70 g/L) with concomitant suppression of other immunoglobulins, a small IgG restriction, and a parotid biopsy revealing lymphoplasmacytic infiltrate with slight kappa light chain excess all suggested a lymphoproliferative disorder (LPD).

Peripheral lipid oxidative stress markers are related to vascular risk factors and subcortical small vessel disease.

Subcortical white matter hyperintensities (WMH), presumed to indicate small vessel ischemic vascular disease, are found commonly in elderly individuals with and without Alzheimer's disease (AD). Oxidative stress may instigate or accelerate the development of vascular disease, and oxidative stress markers are elevated in AD. Here, we assess independent relationships between three serum lipid peroxidation markers (lipid hydroperoxides [LPH], 8-isoprostane, and 4-hydroxynonenal) and the presence of extensive subcortical WMH and/or AD.

Extended Stability of Sodium Phosphate Solutions in Polyvinyl Chloride Bags.

Background: Sodium phosphate injection is used to treat moderate to severe hypophosphatemia. There have been no published reports documenting the physical compatibility or chemical stability of sodium phosphate injection in IV solutions.

Objective: To evaluate the physical compatibility and chemical stability of 30 and 150 mmol/L solutions of phosphate, prepared from sodium phosphate injection, in 5% dextrose in water (D5W) and in 0.

Peripheral inflammatory markers indicate microstructural damage within periventricular white matter hyperintensities in Alzheimer's disease: A preliminary report.

Introduction: White matter hyperintensities (WMH) presumed to reflect cerebral small vessel disease and increased peripheral inflammatory markers are found commonly in Alzheimer's disease (AD), but their interrelationships remain unclear.

Methods: Inflammatory markers were assayed in 54 elderly participants ( = 16 with AD). Periventricular WMH were delineated from T1, T2/proton density, and fluid-attenuated magnetic resonance imaging using semiautomated fuzzy lesion extraction and coregistered with maps of fractional anisotropy (FA), a measure of microstructural integrity assessed using diffusion tensor imaging.

Value of reflex testing based on hypogammaglobulinemia as demonstrated in serum protein electrophoresis.

Objectives: Hypo-gammaglobulinemia (hypoGG) in serum protein electrophoresis (SPE) reflects, variably, reduced serum immunoglobulin (Ig) concentrations, which may be caused by hematological neoplasms, among other causes. HypoGG in the absence of a discernible M-spike (MC) has been the basis of reflexive testing e.g.

Measurement uncertainty for serum free light chain assays: estimation and implication on result interpretation.

Objectives: To estimate the measurement uncertainty (MU) and reference change value (RCV) for serum free light chain assays (sFLC), and to review their implications on result interpretation.

Design And Methods: Data from 6 to 9months of internal QC and up to 3.5years of EQA results were collected retrospectively, on the Roche Modular P analyzer and Dade Behring BN II nephelometer from two independent laboratories.

Validating urinary measurement of beta-2-microglobulin with a Roche reagent kit designed for serum measurements.

Objective: To validate the use of a Roche serum beta-2-microglobulin (B2MG) kit for urinary B2MG measurements, and to establish reference limits for urinary B2MG/creatinine ratio from healthy individuals.

Design And Methods: The Roche B2MG Tina-Quant serum kit was used to measure urinary B2MG immunoturbidimetrically.

Results: Using human urine as a diluent, the B2MG method was linear from 73-2156 μg/L.

Evaluation of a point-of-care glucose meter for general use in complex tertiary care facilities.

Objective: To evaluate the performance of the StatStrip glucose meter from Nova Biomedical for use in complex tertiary care facilities.

Methods: Performance evaluation was conducted in 6 clinical locations involving nurse end-users. Imprecision (CV)<5% was considered acceptable.

An improved assay for plasma methylmalonic acid using chemical ionization gas chromatography mass spectrometry.

Objectives: To develop a precise and sensitive assay for methylmalonic acid (MMA) using positive chemical ionization gas chromatography mass spectrometry (CI GC-MS), and to illustrate its clinical utility.

Methods: Using the developed assay, reference intervals were determined with 108 ambulatory individuals, and potential clinical utility examined in 178 consecutive patients with possible cobalamin deficiency (serum B12<200 nmol/L).

Results And Conclusions: Methylmalonic acid measured by CI GC-MS was precise (CV: 4-5%), and sensitive (limit of quantitation: 37 nmol/L).