ABSTRACT
A laboratory made capillary electrophoresis (CE) system using shorter capillary column was designed and constructed in our research group. This promising CE system was then connected with confocal fluorescence microscopy which was also developed in our research group. In order to show the applicability of this new system on chiral separation of DL-tryptophan (DL-Trp), studies were undertaken using cyclodextrins (CDs) and their derivatives; sulfated (S-CDs) and highly sulfated cyclodextrins (HS-CDs) as chiral selectors. Different selector concentrations were tested at various pH levels (pH 2.5, 4.0, 6.0, 9.0) to optimize the separation conditions. The best results were achieved at lower pH values (e.g. pH 2.5 and pH 4.0). HS-beta-CD and HS-gamma-CD were found to be the most effective chiral selectors with a shorter retention time at low selector concentrations.
Subject(s)
Electrophoresis, Capillary/methods , Tryptophan/chemistry , Cyclodextrins/chemistry , Hydrogen-Ion Concentration , StereoisomerismABSTRACT
Carbohydrates are interesting starting materials for scientific and industrial syntheses as they allow a versatile chemistry. Moreover, they are of natural origin and environmentally benign. During the past few years, inositol, a rather "exotic" carbohydrate, and its derivatives have gained increasing attention. Here, we describe the syntheses of new regiochemically defined inositol monoethers and monoesters as well as regioisomeric inositol ester mixtures and investigate their amphitropic liquid crystallinity. Furthermore, first results on their surface activity in aqueous solutions are given and compared with classical sugar surfactants.
ABSTRACT
Carbohydrates are an attractive class of starting materials for organic syntheses because they are of natural origin, environmentally friendly, and highly functionalized, in this way promoting a sustainable chemistry. A somewhat exotic but nevertheless readily available family of carbohydrates allowing a fascinating chemistry are inositols (cyclohexane-1,2,3,4,5,6-hexols), which we currently use for the synthesis of new surfactants. In our previous work, we reported on the synthesis of a number of new regiochemically defined myo-inositol ethers and esters and studied their surface activity in aqueous solution as well as their ability to form thermotropic liquid crystals. It turned out that the hydrophilicity of the myo-inositol head group alone does not ensure sufficient water solubility of these surfactants. To improve the water solubility, we increased the inositol head group by the introduction of a tri(ethylene oxide) unit. The resulting surfactant is the first representative of a new class of inositol-based surfactants (CiEjIk) that combine the properties of classical sugar surfactants (CnGm) and oligo(ethylene oxide) alkyl ether surfactants (CiEj).
ABSTRACT
BACKGROUND: Renal transplantation is the most effective therapy in end-stage renal disease. The prognosis of transplant survival is still determined by rejection. Morphologically, this involves interstitial rejection with potential development of vascular rejection (VR) and/or glomerular rejection processes, designated as transplant glomerulopathy (TGP). The cellular infiltrates are usually dominated by lymphocytes and macrophages in differing quantity, characterizing the severity of the rejection processes. METHODS: In 14% of the renal transplant biopsies and explants in our investigation (n = 399) plasma cells (PR) predominate in the cellular infiltrate. To determine whether the enrichment of PR has an impact on graft function or could even constitute an independent parameter for transplant survival, we analyzed 109 cases of transplanted patients matched for AR and CR and divided them into those rich and those nonrich in PR. RESULTS: In the group rich in PR, PR comprised 30% of all infiltrates in comparison to 5% in the group non-rich in PR. VR and TGP appeared significantly more often in PR-rich rejections (P = 0.0044). The group rich in PR had a significantly more adverse prognosis (P = 0.0024), especially if PR enrichment was observed in the chronic rejection processes (P = 0.0148). In the Cox proportional hazard model the occurrence of VR was the only independent factor. CONCLUSION: In itself, plasma-cell enrichment is not a prognostic marker, but it is an indicator of a more adverse outcome because it is often accompanied by the appearance or subsequent development of VR +/- TGP. The detection of PR-rich rejection processes should therefore encourage the clinician to intensify the immunosuppressive schedule.
