Novel Activity of Oral Hypoglycemic Agents Linked with Decreased Formation of Tryptophan Metabolite, Kynurenic Acid.

Kynurenic acid is a tryptophan (Trp) metabolite formed along the kynurenine (KYN) pathway in the brain and in peripheral tissues. The disturbed formation of kynurenic acid, which targets glutamate-mediated neurotransmission, GPR35, and aryl hydrocarbon receptors of immune or redox status, was implicated in the development of neuropsychiatric and metabolic disorders among others. Kynurenic acid exerts neuroprotective and immunomodulatory effects, yet its high brain levels may negatively impact cognition.

Kynurenine Pathway in Diabetes Mellitus-Novel Pharmacological Target?

The tryptophan-kynurenine pathway (Trp-KYN) is the major route for tryptophan conversion in the brain and in the periphery. Kynurenines display a wide range of biological actions (which are often contrasting) such as cytotoxic/cytoprotective, oxidant/antioxidant or pro-/anti-inflammatory. The net effect depends on their local concentration, cellular environment, as well as a complex positive and negative feedback loops.

The evolution of the anterior capsulotomy.

The paper describes the development of the anterior capsulotomy from its early crude beginnings in the 18 century to the possibility of automated surgery today via continuous curvilinear capsulorhexis (CCC). The reasons for the opening of the capsule have changed from a roughly made tear to allow access to the nucleus for its extraction, to the creation of more regular openings to allow support for intraocular lenses. With the development of continuous circular tears it was possible to be certain to contain the intraocular lens (IOL) in the capsular bag.