Antiproliferative Activity of Fucan Nanogel

Sulfated fucans comprise families of polydisperse natural polysaccharides based on sulfated L-fucose. Our aim was to investigate whether fucan nanogel induces cell-specific responses. To that end, a non toxic fucan extracted from Spatoglossum schröederi was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution with hydrophobic chains was close to 100%, as estimated by elemental analysis. SNFfuc in aqueous media had a mean diameter of 123 nm and zeta potential of −38.3 ± 0.74 mV, as measured by dynamic light scattering. Nanoparticles conserved their size for up to 70 days. SNFuc cytotoxicity was determined using the MTT assay after culturing different cell lines for 24 h. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0%–43.7% at nanogel concentrations of 0.05–0.5 mg/mL and rabbit aorta endothelial cells (RAEC) non-tumor cell line proliferation displayed inhibition of 8.0%–22.0%. On the other hand, nanogel improved Chinese hamster ovary (CHO) and monocyte macrophage cell (RAW) non-tumor cell line proliferation in the same concentration range. The antiproliferative effect against tumor cells was also confirmed using the BrdU test. Flow cytometric analysis revealed that the fucan nanogel inhibited 786 cell proliferation through caspase and caspase-independent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle.     

Chitosan-Genipin Microspheres for the Controlled Release of Drugs: Clarithromycin,Tramadol and Heparin

The aim of this study was to first evaluate whether the chitosan hydrochloride-genipin crosslinking reaction is influenced by factors such as time, and polymer/genipin concentration, and second, to develop crosslinked drug loaded microspheres to improve the control over drug release. Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained. Microspheres were characterized in terms of size, morphology, drug content, surface charge and capacity to control in vitro drug release. Clarithromycin, tramadol hydrochloride, and low molecular weight heparin (LMWH) were used as model drugs. The obtained particles were spherical, positively charged, with a diameter of 1–10 μm. X-Ray diffraction showed that there was an interaction of genipin and each drug with chitosan in the microspheres. In relation to the release profiles, a higher degree of crosslinking led to more control of drug release in the case of clarithromycin and tramadol. For these drugs, optimal release profiles were obtained for microspheres crosslinked with 1 mM genipin at 50 ºC for 5 h and with 5 mM genipin at 50 ºC for 5 h, respectively. In LMWH microspheres, the best release profile corresponded to 0.5 mM genipin, 50 ºC, 5 h. In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres. However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs.     

Differences and similarities in DNA-binding preferences of MyoD and E2A protein complexes revealed by binding site selection

A technique was developed for studying protein-DNA recognition that can be applied to any purified protein, partially purified protein, or cloned gene. From oligonucleotides in which particular positions are of random sequence, that subset to which a given protein binds is amplified by the polymerase chain reaction and sequenced as a pool. These selected and amplified binding site (SAAB) "imprints" provide a characteristic set of preferred sequences for protein binding. With this technique, it was shown that homo- and heterooligomers of the helix-loop-helix proteins MyoD and E2A recognize a common consensus sequence, CA--TG, but otherwise bind to flanking and internal positions with different sequence preferences that suggest half-site recognition. These findings suggest that different combinations of dimeric proteins can have different binding sequence preferences.     

Hemoglobin variants in Koreans: hemoglobin G Taegu

Hemoglobin G Taegu, an electrophoretically slow hemoglobin with a structural anomaly believed to be in the beta-T-3 section of the beta chain, was the only variant found among 6700 normal Koreans. Four subjects, 0.06 percent, had the G-hemoglobin variant in addition to normal hemoglobin A. Hemoglobin E, known in numerous groups from Southeast Asia and the variant most frequently seen in Chinese subjects, was not found among the Koreans we tested.     

Physico-chemical and sensory properties of formulated syrup from black plum (Vitex doniana) fruit

The fresh ripe fruit pulp and syrup, produced using the open pan evaporator, ofVitex doniana were analysed physico-chemically. Results show that the edible pulp of the ripe fruit is fairly rich in vitamin C (18.1 mg/100 ml) but acidic (pH 4.38) and poor in protein (0.82%) and oil (0.56%). The syrup yielded a DE value of 52, total dissolved solids content of 67° Brix and a refractive index of 1.4762 at 20°C. The syrup was moderately visous (2.1 Poiseuille), acid (pH 4.45) but relatively poor in vitamin C (2.8 mg/100 ml) and protein (0.3%). Sensory evaluation showed no significant difference (p0.05) in taste, flavor and overall acceptability betweenV. doniana syrup and honey. Both physico-chemical and sensory results indicate that the syrup was highly desirable and can substitute for other syrups as a nutritive sweetener.     

Collaborative development of the Arrowsmith two node search interface designed for laboratory investigators

Arrowsmith is a unique computer-assisted strategy designed to assist investigators in detecting biologically-relevant connections between two disparate sets of articles in Medline. This paper describes how an inter-institutional consortium of neuroscientists used the UIC Arrowsmith web interface http://arrowsmith.psych.uic.edu in their daily work and guided the development, refinement and expansion of the system into a suite of tools intended for use by the wider scientific community.     

The effect of Dual® on the flavor of riced baked potatoes

Samples of Katahdin potatoes (Solanum tuberosum) from untreated and Dual 8E-treated plots (4 lb. ai/A applied at the first hilling) were evaluated for flavor by a sensory panel of 21 members. No off-flavor was associated with the Dual-treated baked potatoes.