An in cellulo-activated multicolor cell labeling approach used to image dying cell clearance.

Dying cell clearance is critical for myriad biological processes such as tissue homeostasis. We herein report an enzyme-activated fluorescence cell labeling approach and its use for multicolor imaging of dying cell clearance. Diacetylated 4-hydroxymandelic acid (DHA)-conjugated dyes give rise to reactive quinone methides upon deacetylation in live cells, which in turn covalently labels cellular proteins. With partner cells tagged with distinct fluorescence, apoptotic cell clearance by Raw 264.7 macrophages and epithelial HeLa cells was captured by confocal microscopy, showing the potential of DHA-based cell labeling for investigating cell-cell interactions.

[Synthesis of new mandelic acid derivatives with preservative action. Synthesis and acute toxicity study]. / Sinteza unor noi derivati ai acidului mandelic cu actiune conservanta. Sinteza si studiul toxicitatii acute.

Starting from the antiseptic action of DL mandelic acid, there were synthesized a series of esters of the mandelic acid, esters which could have preservative action. This study present the synthesis, structure validation and the acute toxicity study, for the new synthesized compounds. The esters were obtained by acylating 4-hydroxybenzoic acid propyl, ethyl, methyl esters and salicylic acid with the DL mandelic chloride (that was protected initially by the hydroxylic group). The structure of the synthesized compounds was confirmed by quantitative elemental analysis and RMN 1H spectral measurements. The acute toxicity was determined for two of the esters, who proved to had a preservative action (previously studied) and indicated that these esters have a small toxicity.

Mandelic acid condensation polymer: novel candidate microbicide for prevention of human immunodeficiency virus and herpes simplex virus entry.

Presently marketed vaginal barrier methods are cytotoxic and damaging to the vaginal epithelium and natural vaginal flora when used frequently. Novel noncytotoxic agents are needed to protect men and women from sexually transmitted diseases. One novel candidate is a mandelic acid condensation polymer, designated SAMMA. The spectrum and mechanism of antiviral activity were explored using clinical isolates and laboratory-adapted strains of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). SAMMA is highly effective against all CCR5 and CXCR4 isolates of HIV in primary human macrophages and peripheral blood mononuclear cells. SAMMA also inhibits infection of cervical epithelial cells by HSV. Moreover, it exhibits little or no cytotoxicity and has an excellent selectivity index. SAMMA, although not a sulfonated or sulfated polymer, blocks the binding of HIV and HSV to cells by targeting the envelope glycoproteins gp120 and gB-2, respectively, and also inhibits HSV entry postattachment. SAMMA is an excellent, structurally novel candidate microbicide that warrants further preclinical evaluation.