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A new series of chelate stabilized aryl halide coordination complexes of molybdenum are prepared by a novel oxidative addition strategy; quantitative equilibrium measurements suggest that the structure of the chelate ring, rather than the identity of the halide (X = Cl, Br, I), controls the strength of aryl halide binding in these complexes.

The water flux through preparations of porcine aorta has been investigated. After an initial unsteady period a stable flux of approximately 2 mul/cm2-h was reached and this flux rate remained constant for several hours. Under the experimental conditions which were maintained (110 mm Hg pressure drop across a 2 mm thick section of tissue) this total flux corresponds to a hydraulic conductivity of less than or equal to 7.0 X 10(-13) cm4/dyne-sec. Since these data were obtained in tissue samples where the endothelial layer was not intact, they represent values which are in fact larger than the actual in vivo condition where the endothelial barrier would serve as an additional resistance. Thus, they demonstrate that the transmural flux of water across the aorta wall in vitro due to a pressure gradient is extremely small and, therefore, that other mass transfer mechanisms may be significant.

(3S,5R)-1-Ethynyl-2-methyl-3,5-bistrimethylsilyloxycyclohexene (7), prepared from the optically active lactone 2-methylcyclohexene-3,5-carbolactone (1), was combined with 9α-chloro-des-AB-cholestan-8-one {5α-chloro-1β-[(1R)-1,5-dimethylhexyl]-7aβ-methyl-trans-perhydroindan-4-one}(8) to give the chlorohydrin (9), from which, in turn, 1α-hydroxyprecalciferol3 diacetate (11), and 1α-hydroxyvitamin D3(12; R = H) were obtained.

Highly specific proton line-broadening and paramagnetic 13C shifts observed for N-butyl-N(4-methyloxazol-2-yl)-2-methylpropionamide in the presence of fluorinated lanthanide shift reagents, are absent when non-fluorinated reagents are used. This unusual behaviour is rationalized in terms of possible chelation of the N-butyl-N(4-methyloxazol-2-yl)-2-methylpropionamide to the lanthanide reagent, causing transfer of the unpaired electron into the heterocyclic ring.

Measurements of the extracellular space (ECS) of the isolated swine thoracic aorta were performed with both [14C]inulin and transient measurements and appeared to have better access to available tissue water than the [14C]sucrose gave more consistent results in available tissue water than the [14C]inulin. With [14C]sucrose as the tracer, no significant difference in the ECS was found when the tissue was incubated for 1.5 h in the presence of oxygen and glucose as compared to an incubation in which both oxygen and glucose were absent. However, the ion contents were markedly altered by this change in incubation medium. When oxygen and glucose were present tissue K+ was significantly higher and tissue Na+ was significantly lower than when these metabolites were deleted from the medium. Thus, significant alteration in ion content did not lead to substantial cell damage or bursting.

Expression of human tumor necrosis factor-alpha (TNF) and four different TNF analogs has been studied in Pichia pastoris by utilizing the alcohol oxidase gene promoter. TNF expression level in certain transformants accounted for as much as 36% of the soluble protein. TNF expression was stably maintained during high cell density fermentation (100 g dry cell weight/liter) resulting in a TNF production level of 6-10 g/liter. TNF contained in P. pastoris cell lysates was biologically active as determined by its cytotoxic effect on murine L-929 fibroblast cells and the bioactivity was retained for at least 6 months in the lysates stored frozen at -20 degrees C in the presence of protease inhibitor PMSF. TNF expressed in P. pastoris was recognized by monoclonal antibodies prepared against recombinant Escherichia coli derived TNF. TNF purified from P. pastoris has the expected N-terminal amino acid sequence and specific activity of 10(7) units/mg protein. TNF analogs were also expressed at levels comparable to that of native TNF. Three of the four analogs were insoluble when produced in P. pastoris.

Background Enzyme prodrug therapy shows promise for the treatment of solid tumors, but current approaches lack effective/safe delivery strategies. To address this, we previously developed three enzyme-containing fusion proteins targeted via annexin V to phosphatidylserine exposed on the tumor vasculature and tumor cells, using the enzymes L-methioninase, purine nucleoside phosphorylase, or cytosine deaminase. In enzyme prodrug therapy, the fusion protein is allowed to bind to the tumor before a nontoxic drug precursor, a prodrug, is introduced. Upon interaction of the prodrug with the bound enzyme, an anticancer compound is formed, but only in the direct vicinity of the tumor, thereby mitigating the risk of side effects while creating high intratumoral drug concentrations. The applicability of these enzyme prodrug systems to treating prostate cancer has remained unexplored. Additionally, target availability may increase with the addition of low dose docetaxel treatment to the enzyme prodrug treatment, but this effect has not been previously investigated. To this end, we examined the binding strength and the cytotoxic efficacy (with and without docetaxel treatment) of these enzyme prodrug systems on the human prostate cancer cell line PC-3. Results All three fusion proteins exhibited strong binding; dissociation constants were 0.572 nM for L-methioninase-annexin V (MT-AV), 0.406 nM for purine nucleoside phosphorylase-annexin V (PNP-AV), and 0.061 nM for cytosine deaminase-annexin V (CD-AV). MT-AV produced up to 99% cell death (p

An NMR method is described for assaying the enantiomer composition of the pharmacologically active material penicillamine (1), using tris-(3-heptafluorobutyryl-d-camphorato)europium. The L enantiomer can be detected at levels of 0·4 to 0·5% in DL mixtures. Problems due to the insolubility of penicillamine in nonpolar solvents can be overcome by a two step derivatisation procedure.