Perioperative plasma concentrations of stable nitric oxide products are predictive of cognitive dysfunction after laparoscopic cholecystectomy.

In this study our objectives were to determine the incidence of postoperative cognitive dysfunction (POCD) after laparoscopic cholecystectomy under sevoflurane anesthesia in patients aged >40 and <85 yr and to examine the associations between plasma concentrations of i) S-100beta protein and ii) stable nitric oxide (NO) products and POCD in this clinical setting. Neuropsychological tests were performed on 42 ASA physical status I-II patients the day before, and 4 days and 6 wk after surgery. Patient spouses (n = 13) were studied as controls. Cognitive dysfunction was defined as deficit in one or more cognitive domain(s). Serial measurements of serum concentrations of S-100beta protein and plasma concentrations of stable NO products (nitrate/nitrite, NOx) were performed perioperatively. Four days after surgery, new cognitive deficit was present in 16 (40%) patients and in 1 (7%) control subject (P = 0.01). Six weeks postoperatively, new cognitive deficit was present in 21 (53%) patients and 3 (23%) control subjects (P = 0.03). Compared with the "no deficit" group, patients who demonstrated a new cognitive deficit 4 days postoperatively had larger plasma NOx at each perioperative time point (P < 0.05 for each time point). Serum S-100beta protein concentrations were similar in the 2 groups. In conclusion, preoperative (and postoperative) plasma concentrations of stable NO products (but not S-100beta) are associated with early POCD. The former represents a potential biochemical predictor of POCD.

Determination of the absolute configuration of synthetic pterocarpans by chiral HPLC using on-line CD detection.

Resolution of synthetic racemic pterocarpans was achieved by CD monitored HPLC using a chiral stationary phase. No sign of exciton coupling was seen in the CD spectra of the pterocarpan enantiomers. The predominance of the chromane chromophore was indicated by the high intensity of the (1) L(b) band. The chirality of both the chromane and dihydrobenzo[b]furane chromophores was found to be governed by the second chiral sphere. An oxygen atom in pseudoaxial position at the benzylic atom of the chroman ring system gave rise to an increased third-sphere contribution and the positive sign of the (1) L(b) and negative sign of the (1) L(a) band. This resulted in a general positive-negative-negative sign pattern of the (1) L(b), (1) L(a) and (1) B(b) bands of the second-eluted enantiomer of P helicity suggesting homochirality and the same absolute configuration of the chiral centers.

Niveles de hormona de crecimiento y somatomedina C en niños con desnutrición grave / Malnutrition in children growth and somato medine C

La desnutrición se acompaña de modificaciones importantes en los niveles hormonales plasmáticos como parte de sus mecanismos adaptativos que permiten la sobrevida; devido al alto índice de desnutridos en nuestro medio, la motivación para esta investigación fue conocer como se comportan nuestros pacientes en relación a lo descrito en la literatura. Se evaluaron 20 niños desnutridos graves (13 Kwashiorkor y 7 Marasmo-Kwashiorkor) en edades comprendidas entre un mes y tres años, al ingreso, a los 15 días, al mes y a los dos meses de la recuperación. Las variables estudiadas fueron: edad, antropometría, escore de McLaren, niveles hormonales plasmáticos (Hormona de Crecimiento, IGF-1). Al ingreso los valores de hormona de crecimiento fueron elevados, disminuyendo significativamente (p<0,05) a los dos meses de la rehabilitación nutricional, en contraste los niveles de IGF-1 fueron bajos al ingreso, aumentando significativamente (p<0,05) a los dos meses de la recuperación. Los niveles altos de hormona de crecimiento pudieran ser explicados por la ausencia de retrocontrol ejercido normalmente por los niveles de IGF-1 que se encuentran disminuidos. El mejor entendimiento de los cambios hormonales en la desnutrición podrá conducir al uso terapeútico de ciertas hormonas tanto en la rehabilitación nutricional como en efermedades acompañadas de desnutrición