he HPLC columns were 18 kept at 27.8C. The mobile phase was delivered at a flow-rate of 1.0 ml/min, with the following stepwise gradient elution program: A-B (60:40) at 0 min→(40:60) at 30 min→(40:60) at 60 min. Solvent A contained 10 mM tetrabutylammonium hydroxide, 10 mM KH PO and 0.25% MeOH, and was adjusted to pH 6.9 with 1 M HCl. Solvent B consisted of 5.6 mM 24 tetrabutylammonium hydroxide, 50 mM KH PO and 30% MeOH, and was neutralized to pH 7.0 with 1 M NaOH. The 24 calibration curves (r.0.99) of the components in cell extracts were established with their aqueous standards. The average within-day precision for the nine compounds was 0.9%, and the average day-to-day precision was 5.0%. The detection limits (pmol) of the nine reagents were 1.39 (ADP), 4.32 (CTP), 15.5 (dCTP), 2.38 (GTP), 4.42 (UTP), 9.45 (dGTP), 14.6 (dTTP), 2.44 (ATP) and 11.8 (dATP). The recovery of this method for the standards ranged from 82.4 to 120.5%. The results for the detection of nucleotide pools in 16 normal and tumor cell lines were presented. In conclusion, this simplified analytical method enables the simultaneous quantitation of NTP and dNTP in cell or tissue extracts and may represent a valuable tool for the detection of minute alterations of intracellular NTP/dNTP pools induced by anticancer/antiviral drugs and diseases.

We constructed a biologicmaterial composedoffetal ratbrain cells (neurospheres) and adult rat bone marrow stromal cells (MSCs), designated as NMCspheres Adult rats were subjected to 2 hours of middle cerebral artery occlusion (MCAo) and implanted with cultured prelabeled NMCspheres (n=6), neurospheres (n=5) or MSCs (n=6) into the ischemic penumbra at 24 hours after MCAo. Control adult rats (n=10) were subjected to MCAo alone. In vitro within the NMCspheres, MSCs rapidly fonned a process network with intact neural cells compared with a necrotic core within neurospheres alone An in vivo rat corneal assay demonstrated that NMCspheres enhanced angiogenesis compared to MSCs and neurospheres Neurological functional recovery after stroke was enhanced in rats trcated with NMCspheres, compared to rats with neurosphere or MSC treatments by day 7 and day 14 after transplantation. The NMCspheres are a new compositc material that may be employed in the treatment of stroke

The present study investigates the induction of neurogenesis, reduction of apoptosis, and promotion of basic fibroblast growth factor (bFGF) expression as possible mechanisms by which treatment of stroke with bone marrow stromal cells (MSCs) improves neurological functional recovery. Additionally, for the first time, we treated cerebral ischemia in female rats with intraveneous administration of MSCs. Female rats were subjected to 2 hr of middle cerebral artery occlusion (MCAo), followed by an injection of 3

Three novel taxinine analogues were prepared and tested for their activity as multidrug resistance (MDR) reversal agents in comparison with verapamil. In vitro testing demonstrated that compounds 8-10 possess MDR-reversal activity in the KB/V cell line. Half-hour after treatment with 5, 10, and 20lmol/L compound 9, the intracellular rhodamine123 concentration increased 2.3, 2.9, and 3.2-fold, respectively, higher than 1.88-fold of 10lmol/L verapamil in KB/V cell line. In vivo studies with VCR-resistant KB/V tumor xenografts showed that compound 9 in combination with VCR significantly inhibited tumor growth. Treatment with VCR or 9 alone did not result in growth inhibition. These results reveal that three taxinine analogues are good modifiers of MDR in tumor cells.