Lipidic Profiles of Patients Starting Peritoneal Dialysis Suggest an Increased Cardiovascular Risk Beyond Classical Dyslipidemia Biomarkers

Background. Lipids are molecules that constitute a fundamental part of the plasma. Chronic kidney disease (CKD) produces profound changes in lipid metabolism, and associated lipid disorders, in turn, contribute to the progression of CKD. Patients on peritoneal dialysis (PD) have more atherogenic lipid profiles than non-dialysis-dependent CKD patients. Methods. Single-center prospective observational study of a cohort of CKD patients who started renal replacement therapy with continuous ambulatory peritoneal dialysis. The differences in the lipid profile and analytical variables before and six months after the start of peritoneal dialysis were analyzed. Samples were analyzed on an Ultra-Performance Liquid Chromatography system. Results. Thirty-nine patients were enrolled in this study. Their mean age was 57.9 ± 16.3 years. A total of 157 endogenous lipid species of 11 lipid subclasses were identified. There were significant increases in total free fatty acids (p< 0.05), diacylglycerides (p <0.01), triacylglycerides, (p <0.01), phosphatidylcholines (p <0.01), phosphatidylethanolamines (p <0.01), ceramides (p <0.01), sphingomyelins (p <0.01), and cholesterol esters (p<0.01) from baseline to 6 months. However, there were no differences in the classical lipid markers, neither lysophosphatidylcholines, monoacylglycerides, and sphingosine levels. Conclusions. Patients on PD present changes in the lipidomic profile beyond the classic markers of dyslipidemia, that suggest an increased cardiovascular risk in them.

Cerebrospinal fluid glutamate changes in functional movement disorders

The aim of this study was to assess cerebrospinal fluid (CSF) concentrations of specific amino acids using a high-performance liquid chromatography system in a sample of patients with functional movement disorders (FMDs) and in a sample of controls. CSF levels of glutamate were significantly lower in patients with FMD than in controls. This finding argues in favor of glutamatergic dysfunction in the pathophysiology of FMD.

Production of Recombinant Gelonin Using an Automated Liquid Chromatography System

Advances in recombinant DNA technology have opened up new possibilities of exploiting toxic proteins for therapeutic purposes. Bringing forth these protein toxins from the bench to the bedside strongly depends on the availability of production methods that are reproducible, scalable and comply with good manufacturing practice (GMP). The type I ribosome-inhibiting protein, gelonin, has great potential as an anticancer drug, but is sequestrated in endosomes and lysosomes. This can be overcome by combination with photochemical internalization (PCI), a method for endosomal drug release. The combination of gelonin-based drugs and PCI represents a tumor-targeted therapy with high precision and efficiency. The aim of this study was to produce recombinant gelonin (rGel) at high purity and quantity using an automated liquid chromatography system. The expression and purification process was documented as highly efficient (4.4 mg gelonin per litre induced culture) and reproducible with minimal loss of target protein (~50% overall yield compared to after initial immobilized metal affinity chromatography (IMAC)). The endotoxin level of 0.05–0.09 EU/mg was compatible with current standards for parenteral drug administration. The automated system provided a consistent output with minimal human intervention and close monitoring of each purification step enabled optimization of both yield and purity of the product. rGel was shown to have equivalent biological activity and cytotoxicity, both with and without PCI-mediated delivery, as rGelref produced without an automated system. This study presents a highly refined and automated manufacturing procedure for recombinant gelonin at a quantity and quality sufficient for preclinical evaluation. The methods established in this report are in compliance with high quality standards and compose a solid platform for preclinical development of gelonin-based drugs.

Metabolism study of morpholinium 2- ((4- (2-methoxyphenyl)-5-(pyridin-4-yl) -4H-1,2,4-triazole-3-yl)thio) acetate

Aim. The purpose of this study is to reveal the determination of the structure of the main metabolite of morpholinium 2-(4-(2-methoxyphenyl)-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-yl)thio)acetate (an active pharmaceutical ingredient – API) by way of chromatography through mass spectrometry detection, utilizing the liquid chromatography system Agilent 1260 Infinity and mass spectrometry detector (single quadrupole detector Agilent 6120). In the work, the graph of the change in the area of the peak of the metabolite from time after the introduction of the API solution was constructed. Moreover, the charges on the atoms of 2-((4-(2-methoxyphenyl)-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-yl)thio) acetate were calculated and the structure of the methyl derivative was proposed. We saw that the methylation of the active substance during metabolism formed a 5-((carboxymethyl)thio)-4-(2-methoxyphenyl)-1-methyl-3-(pyridin-4-yl)-4H-1,2,4-triazol-1-um cation through N-methyltransferase.