Objective: To investigate the metabolic effects of two different formula of amino acids on postoperative patients . Methods: According to prospective ,randomized , single blind and controlled rule, 120 patients after abdominal operation were randomized to receive parenteral nutrition with either amino acid enriched BCAA or balanced amino acid (18 F).From the second day after operation, total parenteral nutrition was infused to the patients with equal calorie and equal nitrogen by central or peripheral vein for 6 days. Meanwhile, every day nitrogen balance was monitored by collecting urine in 24 hours .The indices were investigated such as amino acids patterns, and serum levels of total protein, albumin, prealbumin, thansferrin and fibronectin. Results: Nitrogen balance of patients in study group on day5 was higher than those of control group. The decreased serum levels of albumin in study group were lower than the control group. Concentrations of valine increased more significantly in study group than that of the control group. Conclusions: The formula of amino acid enriched BCAA may be more suitable and effective for the postoperative traumatic patients on protein metabolism.

OBJECTIVETo analyze the influence of retinoic acid (RA) on the undifferentiated state and EB formation abilities of human embryonic stem cells.

METHODSThe biological characteristics of H9 ESCs after RA treatment were characterized by real-time PCR, MTS proliferation assay and immunofluorescence staining. The expression of three germ layers markers, osteogenic differentiation markers and adipogenic differentiation markers in H9-differentiated embryoid bodies (EBs) with RA treatment were quantified by real time PCR.

RESULTSThe proliferation of H9 ESCs in the early logarithmic growth phase was accelerated by RA treatment. In addition, RA induced differentiation of H9 ESC coupled with morphology changes, decreased expression of undifferentiated markers Oct4, Nanog, Sox2 and OCT4 mRNA binding protein Lin28 at mRNA level, and reduced expression of Oct4 at protein level. RA induced formation of cavities in EBs. Real time PCR results showed that the expressions of ectodermal markers: NeuroD1, Noggin; mesodermal markers: Brachyury, Twist and endodermal markers: AFP, GATA-4 were significantly increased (P < 0.05), especially for AFP (P < 0.01), by RA treatment in a dose-dependent manner. In addition, the expression of adipogenic differentiation marker C/EBPalpha was increased while the osteogenic differentiation marker OPN was decreased in EBs after RA treatment for 5 days.

CONCLUSIONSHigh concentrations of RA induced the loss of stemness in H9 ESCs and excessive differentiation in EBs, and damaged the balance between osteogenic and adipogenic differentiation during early EB differentiation, which may be relevant to the congenital malformations.

Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Embryonic Stem Cells ; cytology ; drug effects ; Humans ; Tretinoin ; pharmacology