Plasma Thiols and Taurine Levels in Central Retinal Vein Occlusion

The Phenotypic Characterization of the Cammalleri Sisters, an Example of Exceptional Longevity

This article shows demographic, clinical, anamnestic, cognitive, and functional data as well as biochemical, genetic, and epigenetic parameters of two exceptional siblings: Diega (supercentenarian) and Filippa (semisupercentenarian) Cammalleri. The purpose of this study is to provide new insights into the extreme phenotypes represented by semisupercentenarians and supercentenarians. Different studies have been published on supercentenarians, but to the best of our knowledge, this is the only concerning two sisters and the most detailed from a phenotypic point of view. Our findings agree with the suggestion that supercentenarians have an increasing relative resistance to age-related diseases, approximating the limits of the functional human reserve to address successfully the acute causes of death. More interestingly, our data agree with, and extend, the suggestion that inflammation and oxidative stress predict centenarian mortality.

Capillary Electrophoresis of Free Amino Acids in Physiological Fluids Without Derivatization Employing Direct or Indirect Absorbance Detection

Whole blood and/or plasma amino acids are useful for monitoring whole-body protein and amino acid metabolism in an organism under various physiological and pathophysiological conditions. Various methodological procedures are in use for their measurement in biological fluids. From the time when capillary electrophoresis was introduced as a technology offering rapid separation of various ionic and/or ionizable compounds with low sample and solvent consumption, there were many attempts to use it for the measurement of amino acids present in physiological fluids. As a rule, these methods require derivatization procedures for detection purposes.Here, we present two protocols for the analysis of free amino acids employing free zone capillary electrophoresis. Main advantage of both methods is an absence of any derivatization procedures that permits the analysis of free amino acid in physiological fluids. The method using direct detection and carrier electrolyte consisting of disodium monophosphate (10 mM at pH 2.90) permits determination of compounds that absorb in UV region (aromatic and sulfur containing amino acids, as well as some peptides such as carnosine, reduced, and oxidized glutathione). The other method use indirect absorbance detection, employing 8 mM p-amino salicylic acid buffered with sodium carbonate at pH 10.2 as running electrolyte. It permits quantification of 30 underivatized physiological amino acids and peptides. In our experience factorial design represents a useful tool for final optimization of the electrophoretic conditions if it is necessary.

Homocysteine, methylenetetrahydrofolate reductase C677T polymorphism, and risk of retinal vein occlusion: an updated meta-analysis

Background

To evaluate the role of plasma total homocysteine (tHcy) and homozygosity for the thermolabile variant of the methylenetetrahydrofolate reductase (MTHFR) C677T genotype in the risk of retinal vein occlusion (RVO).

Methods

Relevant studies were selected through an extensive search of PubMed, EMBASE, and the Web of Science databases. Summary weighted mean differences (WMDs) or odds ratios (ORs) and 95% confidence intervals (CI) were calculated with a random-effects model.

Results

Forty-two studies with 6445 participants were included in this updated systematic review and meta-analysis. The mean plasma tHcy level in the RVO patients was significantly higher than in the controls (WMD =2.13 μmol/L; 95% CI: 1.29 to 2.98, P < 0.001), but there was evidence of between-study heterogeneity (P < 0.001). No significant association between MTHFR C677T genotype and RVO was found under all genetic models.

Conclusion

There was some evidence that plasma tHcy is associated with an increased risk of RVO. There was no evidence to suggest an association between homozygosity for the MTHFR C677T genotype and RVO.

Recent advances in amino acid analysis by capillary electrophoresis

This paper describes the most important articles that have been published on amino acid analysis using CE during the period from June 2009 to May 2011 and follows the format of the previous articles of Smith (Electrophoresis 1999, 20, 3078-3083), Prata et al. (Electrophoresis 2001, 22, 4129-4138) and Poinsot et al. (Electrophoresis 2003, 24, 4047-4062; Electrophoresis 2006, 27, 176-194; Electrophoresis 2008, 29, 207-223; Electrophoresis 2010, 31, 105-121). We present new developments in amino acid analysis with CE, which are reported describing the use of lasers or light emitting diodes for fluorescence detection, conductimetry electrochemiluminescence detectors, mass spectrometry applications, and lab-on-a-chip applications using CE. In addition, we describe articles concerning clinical studies and neurochemical applications of these techniques.

Capillary electrophoresis of free amino acids in physiological fluids without derivatization employing direct or indirect absorbance detection

Whole blood and/or plasma amino acids are useful for monitoring whole body protein and amino acid metabolism in an organism under various physiological and pathophysiological conditions. Various methodological procedures are in use for their measurement in biological fluids. From the time when capillary electrophoresis was introduced as a technology offering rapid separation of various ionic and/or ionizable compounds with low sample and solvent consumption, there were many attempts to use it for the measurement of amino acids present in physiological fluids. As a rule, these methods require derivatization procedures for detection purposes.Here, we present two protocols for the analysis of free amino acids employing free zone capillary electrophoresis. Main advantage of both methods is an absence of any derivatization procedures that permits the analysis of free amino acid in physiological fluids. The method using direct detection and carrier electrolyte consisting of disodium monophosphate (10 mM at pH 2.90) permits determination of compounds that absorb in UV region (aromatic and sulfur containing amino acids, as well as some peptides, such as carnosine, reduced and oxidized glutathione). The other method uses indirect absorbance detection, employing 8 mM p-amino salicylic acid buffered with sodium carbonate at pH 10.2 as running electrolyte. It permits quantification of 30 underivatized physiological amino acids and peptides. In our experience, factorial design represents a useful tool for final optimization of the electrophoretic conditions if it is necessary.