QUESTION-- what is the effect of of ddp4 inhibitors on c peptide ?and if increasing it does it mean beta cell regeneration?

RESPONSE--Your questions are good ones and a field of interest of mine.  Namely, can Dpp-4i and/or GLP-1 RAs increase beta cell mass and serve as a potential disease modifying agent in diabetes.The short answer is that the majority of research on this has been done in GLP-1 agents, with less in the DPP-4 arena.  GLP-1 agents have been shown to increase beta cell mass by promoting de novo beta cell generation, promoting beta cell differentiation from other precursor cells types, and increase beta cell survival by resisting apoptosis in ANIMALS (mostly rodent models).  However, this has been proven mostly to not be the case in humans, with the exception that the agents MAY help to reduce apoptosis.
To this end GLP-1 and DPP-4 agents have been pursued in type 1 diabetes to either prevent destruction of remaining cells, or to regenerate old ones.  No studies to date have been successful, but we are currently doing a study with novo nordisk looking at using liraglutide in newly diagnosed type 1 patients (in combination with another immunotheraptueic) to hopefully preserve beta cell mass.   Hope that helps. Jeremy Pettus, MD  California, USA


Use Epinephrine with lidocaine for FNA?
QUESTION-It's common practice to use plain lidocaine with fine needle aspiration of thyroid nodules. I am wondering if any reason against using  Epinephrine with the Lidocaine for fine needle aspiration  ? Thank you, Rami Mortada, MD, ECNU, FACE ,Endocrine Center of Kansas.

RESPONSE-In our center we perform over 2000 thyroid FNA each year and we never use local anesthesia, similarly to most european centers. The pain of a 25 needle is perfectly tolerable (if the manuver is gently performed) and is probably lower than that induced by the injection of xylocaine. Anyway, there is no advantage in the association of epinefrine to the anesthetic. In the past it was due to the need of inducing a vasoconstriction and so to decrease the risk of bleeding and the permanence of the anesthetic in the tissue to be biopsied. For thyroid FNA this risk is negligible while epinefrine may induce cardiovascular side effects.  So, on the basis of a large clinical practice, I would suggest not to use anesthetics or to use them without the addition of epinephrine.  Enrico Papini, MD   Italy