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During the last decade, capillary electrophoresis (CE) has emerged as an interesting alternative to traditional analysis of serum, plasma and urine proteins by agarose gel electrophoresis. Initially there was a considerable difference in resolution between the two methods but the quality of CE has improved significantly. We thus wanted to evaluate a second generation of automated multicapillary instruments (Capillarys, Sebia, Paris, France) and the high resolution (HR) buffer for serum or plasma protein analysis with an automated agarose gel electrophoresis system for the detection of M-components. The comparison between the two systems was performed with patients samples with and without M-components. The comparison included 76 serum samples with M-components > 1 g/L. There was a total agreement between the two methods for detection of these M-components. When studying samples containing oligoclonal bands/small M-components, there were differences between the two systems. The capillary electrophoresis system detected a slightly higher number of samples with oligoclonal bands but the two systems found oligoclonal bands in different samples. When looking at resolution, the agarose gel electrophoresis system yielded a slightly better resolution in the alpha and beta regions, but it required an experienced interpreter to be able to benefit from the increased resolution. The capillary electrophoresis has shorter turn-around times and bar-code reader that allows positive sample identification. The Capillarys in combination with HR buffer gives better resolution of the alpha and beta regions than the same instrument with the beta1-beta2+ buffer or the Paragon CZE2000 (Beckman) which was the first generation of capillary electrophoresis systems.

Today, eggs with an increased content of -3 fatty acids are available but there are few publications on the effects of consumption of such eggs on the lipoproteins and acute phase markers in humans. The aim of the present study was to evaluate the effects of consumption of standard eggs and -3 enriched eggs on lipoproteins, glucose and inflammation markers. Nineteen healthy volunteers consumed one extra egg per day of either standard eggs or omega-3 enriched eggs in a double-blind, cross-over study. The duration of each period was 1 month. The effects of the different egg diets on apolipoprotein A1 and B (Apo A1 and B), lipoprotein (a), creatinine, cystatin C, C-reactive protein, serum amyloid protein A, interleukin 6, triglycerides, glucose, total-, high-density lipoprotein and low-density lipo-protein cholesterol concentrations were analyzed. Addition of one regular egg per day to the normal diet had no negative impact on blood lipids or inflammation markers. Consumption of omega-3 enriched eggs resulted in higher levels of ApoA1, lower ApoB/ApoA1 ratio and lower plasma glucose. These effects have been associated in previous studies with a reduced risk for cardiovascular mortality and diabetes.

Plasma cystatin C has been shown in several studies to be superior to plasma creatinine for estimation of glomerular filtration rate (GFR). Reporting cystatin C results in mL/min using conversion formulas for transforming cystatin C expressed as mg/L to GFR expressed as mL/min has greatly facilitated the clinical use of the marker. At our hospital we have an increasing demand for cystatin C and at present we perform over 1400 cystatin C analyses a month. The test is available at all hours. This in combination with the volume emphasises the need to have the assay close to the routine chemistry instrument to reduce handling time per test and time to report test results. We have thus evaluated the Dade Behring N Latex Cystatin C assay (Dade Behring, Deerfield, IL, USA) on Architect ci8200 (Abbott Laboratories, Abbott Park, IL, USA). The nephelometric method on the ProSpec (Dade Behring) and the turbidimetric method on Architect ci8200 showed very good agreement (y = 1.0072x + 0.0042; R2 = 0.987). Accordingly, running the cystatin C analyses on a chemistry instrument (Architect ci8200) would be proper to increase the availability of the analysis and reduce turnaround times.

Background: A new automated multicapillary zone electrophoresis instrument with improved resolution buffer (Capillarys with HR buffer, SEBIA, Paris, France) for analysis of human plasma proteins was compared with erythrocyte sedimentation rate (ESR). ESR determinations have been performed for more than eighty years and it is still one of the most frequently used laboratory tests, mainly to monitor the inflammatory response and as a tumour marker., Methods: We studied the relationships between ESR, capillary electrophoresis and nephelometric determination of fibrinogen and albumin in 503 consecutive patient samples. The samples were analyzed on the Capillarys. The albumin concentration from the nephelometric determination was used for quantification of the individual peaks in the capillary electrophoresis electropherogram., Results: We found no significant correlation between presence or size of M-components and ESR. There were moderate to strong correlations between ESR, fibrinogen and capillary electrophoretic determination of alpha1-antitrypsin, alpha1-acid glycoprotein or haptoglobin for the detection of acute phase response., Conclusions: We suggest that ESR could be replaced by capillary electrophoresis for the assessment of inflammatory conditions and to detect M-components.

Background: The kidney function is a major determinant of the serum concentration of digoxin as this drug is mainly eliminated unchanged through the kidneys. Since digoxin is widely prescribed among the elderly, and the glomerular filtration rate (GFR) declines with age, it is important that the clinician takes the patient's GFR into account when prescribing digoxin. Serum cystatin C has been suggested to be superior to creatinine for estimation of GFR, which may have relevance for the optimization of treatment with digoxin., Methods: To evaluate which of the two GFR markers serum creatinine and serum cystatin C that best correlates with serum digoxin, we compared the serum levels of digoxin with the serum levels of creatinine and cystatin C in 149 patients on therapeutic drug monitoring of digoxin at our hospital., Results: Overall, there was a stronger correlation between serum digoxin concentrations and cystatin C (p=0.00001) as compared to creatinine (p= 0.00003). Interestingly, of the patients with a serum digoxin concentration > or = 1.5 nmol/L, 29% had a serum creatinine level within normal limits, as compared to 20% with normal cystatin C levels., Conclusions: In this study, serum cystatin C correlated better to serum digoxin than did serum creatinine. With improved GFR monitoring, digoxin concentrations should be better controlled.

High sensitivity CRP (hsCRP) and serum amyloid component A (SAA) are two acute phase proteins that have been shown to be prognostic markers in cardiovascular diseases. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are two angiogenic growth factors involved in the growth and invasion of solid tumors and hematological malignancies. They also play an important role in cardiovascular and inflammatory diseases. The acute phase response induces the production of angiogenic peptides and angiogenic peptides have also been shown to induce the synthesis of inflammatory cytokines. HsCRP and SAA, bFGF and VEGF in serum and EDTA plasma were measured in samples from 80 human blood donors. There were strong correlations between hsCRP and SAA but there were no significant correlation between hsCRP or SAA and any of the angiogenic peptides. Low-grade inflammation did not induce bFGF or VEGF production.