Effect of fiber diameter on surface morphology,mechanical property,and cell behavior of electrospun poly(ε-caprolactone) mat

In this study, electrospinning of poly(ε-caprolactone) (PCL) and its optimum preparation conditions were examined in detail using various solvent systems, such as formic acid, dichloromethane/dimethyl formamide (DMF), chloroform/DMF, and dichloroethane. The average fiber diameter of the electrospun PCL mat was controlled by the solvent used with a proper concentration of PCL dope solution. Different fiber sizes (0.1, 0.8, 1.9, and 3.4 μm) of uniform PCL mats were fabricated and the effects of fiber size on surface morphology, tensile properties and cell behavior were investigated. Here, we manipulated much broader range of average fiber diameter of the mats, from nano to several micron size of fiber. It was found that the fiber diameter greatly affected topology (surface roughness) and mechanical properties of the electrospun PCL mat and consequently, they influenced the cell behavior (adhesion and proliferation) significantly. We expect that these results will provide more feasible application of electrospun PCL scaffold in tissue engineering through the co-relations in structure and property of PCL fiber mat on cell behavior.     

Studies on the Susceptibility of Water Buffaloes to Leptospira

Eight mature farming type, Taiwan, water buffaloes were inoculate with L. australis A while six received L. canicola. Before inoculation all animals were negative to the microscopic-agglutination test (agglutinationlysis test) using the above species as antigen.

No sign of clinical leptospirosis was observed although four animals developed temperatures.

Cultures made from buffalo blood, kidneys and urine and from blood of guinea pigs inoculated with kidney emulsion and urine from the inoculated buffalo were all negative for leptospiral organisms.

Blood samples drawn from the water buffalo 2, 3 and 4 weeks post inoculation were negative to the microscopic-agglutination test except for one animal. Blood from the animal taken two weeks post-inoculation was positive at 1:100 dilution with L. australis A antigen but that taken at 3 and 4 weeks was negative.

     

Histopathological changes of testes and eyes by neutron irradiation with boron compounds in mice

This study was performed to investigate the biological effects of boron neutron capture therapy (BNCT) on the testes and eyes in mice using HANARO Nuclear Reactor, Korea Atomic Energy Research Institute. BNCT relies on the high capacity of ¹⁰B in capturing thermal neutrons. Sodium borocaptate (BSH, 75 ppm, iv) and boronophenylalanine (BPA, 750 ppm, ip) have been used as the boron delivery agents. Mice were irradiated with neutron (flux: 1.036739E +09, Fluence 9.600200E+12) by lying flat pose for 30 (10 Gy) or 100 min (33 Gy) with or without boron carrier treatment. In 45 days of irradiation, histopathological changes of the testes and eyes were examined. Thirty-three Gy neutron irradiation for 100 min induced testicular atrophy in which some of seminiferous tubules showed complete depletion of spermatogenic germ cells. Lens epithelial cells and lens fiber were swollen and showed granular changes in an exposure time dependent manner. However, boron carrier treatment had no significant effect on the lesions. These results suggest that the examination of histopathological changes of lens and testis can be used as "biological dosimeters" for gauging radiation responses and the HANARO Nuclear Reactor has sufficient capacities for the BNCT.     

Endosulfan Plant Uptake Suppression Effect on Char Amendment in Oriental Radish

Persistent organic pollutants (POPs) immobilization in farm land is an important issue to solve the residue in crop, and char has been considered for the remediation. In here, three commercially available chars like powdered oak char (POC), granulated oak char (GOC), and rice husk char (RHC) including powdered activated carbon (PAC) were investigated for their potential to adsorb and immobilize endosulfan in the soil. The maximum adsorption capacities (mg g^?1) of the applied chars as POC, GOC, and RHC were 714.8, 322.6, and 181.8, respectively, and the capacity of POC was similar with PAC (713.8). In addition, the pore volume (0.138 cm³ g^?1) and the surface area (270.3 m² g^?1) of POC were over 3-fold higher than GOC and RHC. The bioconcentration factor (BCF) reducing effect of α-, β-endosulfan, and endosulfan sulfate in oriental radish (Raphanus sativus var. sativus) was investigated by amendment of three commercially available chars to the contaminated soils. The BCF of total endosulfan was 0.025 in the radish root. POC treatments effectively suppressed the endosulfan uptake (BCF 0.002). However, GOC and RHC showed little BCF reducing effect of endosulfan in radish.     

Synthesis and herbicidal activity of new benzenesulfonylureas

A series of benzenesulfonylurea derivatives possessing a branched hydroxymethyl moiety as an ortho-substituent were synthesized and found to have interesting herbicidal activity under submerged paddy conditions.     

Utility of a Hydrolysate from Overproduced Paralichthys olivaceus for Hypertension Treatment: Correlation between Physical Properties and Potent Anti-Hypertensive Activities

Aquacultured fish are the richest natural source of protein. However, their overproduced biomass is often discarded due to production imbalance, causing considerable losses to the fishery industry. Therefore, it is necessary to utilize surplus fish and add value to overproduced fish. We performed complex enzyme-assisted hydrolysis to determine the correlation between its physical characteristics and anti-hypertensive activity in vitro and in vivo using an SHR model. Protamex-Pepsin assisted hydrolysate from Paralichthys olivaceus (PO_ppH) produced by complex enzyme-assisted hydrolysis contained low-molecular-weight peptides and amino acids with anti-hypertensive activity. PO_ppH regulated blood pressure and serum angiotensin II and angiotensin-I-converting enzyme levels, and histological and ultrasound image analysis revealed substantially reduced thickness and diameter of the carotid aorta in the PO_ppH-administered SHR group. Therefore, we propose to reduce food loss due to overproduction by utilizing the anti-hypertensive activity and physical properties of PO_ppH; the results demonstrate its application as a therapeutic agent.     

Dispersion polymerization of styrene using poly(4-vinylpyridine) macro-RAFT agent under UV radiation

The dispersion polymerization of styrene using a poly(4-vinylpyridine) (P4VP) macromolecular RAFT (macro-RAFT) agent as both a macro-initiator and a colloidal stabilizer under UV radiation was investigated for the first time. The P4VP macro-RAFT agent (M _n,GPC=49,000 g/mol, PDI=1.14) was prepared by the RAFT polymerization of 4-vinylpyridine using 2-cyanoprop-2-yl dithiobenzoate as a chain transfer agent. The resulting polystyrene (PSt) particles had hairy P4VP chains, which could successfully immobilize very small Au nanoparticles on the surface of the PSt particles. It was found that hairy polymeric particles could be produced by photo-initiated dispersion polymerizations of vinyl monomers using macro-RAFT agents that are susceptible to UV radiation as both macro-initiators and colloidal stabilizers.     

Observation of spinline behavior of dual nozzle electrospinning and its fiberweb morphology

The spinline behavior in dual nozzle electrospinning was observed using high shutter speed photography and laser scattering technique. It was found that the spinlines of each nozzle have skewed bell shapes. The solution concentration, the number of nozzles, the nozzle-to-nozzle distance (NND) showed significant effects on both the spinline shape and the fiberweb morphology. They were also resulted from the inter- and the intra-spinline repulsive forces. Especially the fibers collected in the middle of the collecting plate were oriented along the tangential direction to the two webs spun from each nozzle.