In vivo pharmacokinetics of pyribenzoxim in rats

Pyribenzoxim, benzophenone O‐[2,6‐bis(4,6‐dimethoxypyrimidin‐2‐yloxy)benzoyl]oxime, is a new post‐emergence herbicide providing broad‐spectrum weed control in rice fields. [¹⁴C]Pyribenzoxim was used to study the pharmacokinetics of the compound after oral administration of a dose of 1000 mg kg^?1 to male Sprague–Dawley rats. The material balance ranged from 97.3 to 99.7% of the administered dose and urinary and fecal recovery accounted for 97.1%, with the majority of radioactivity recovered in feces (88.6%) by 168 h after treatment. Elimination as volatile products or as carbon dioxide was negligible. The following values were obtained for the compound in the blood: AUC_0–168h, 28400 µg equiv h g^?1; T_max, 12 h; C_max, 372 µg equiv g^?1; half‐life, 53 h. Radioactivity in tissue decreased from 96.1% of applied radiocarbon at 6 h to 0.4% at 168 h and the highest concentration of radioactivity among the tissues was observed in liver while the lowest residues were found in brain. The elimination half‐lives of radioactivity from tissues was in the range of 7 to 77 h and T_max values of 12, 24 and 12 h were observed for blood, liver and kidney, respectively. Except for that in the digestive tract, the tissue‐to‐blood ratio (TBR) was highest in the liver. © 2001 Society of Chemical Industry     

Etiologic and epidemiologic analysis of bacterial infectious upper respiratory disease in Thoroughbred horses at the Seoul Race Park

Infectious upper respiratory disease (IURD) of Thoroughbred racehorses has been a frequent problem (29.6% of incidence) at the Seoul Race Park (Korea). Risk factors for IURD include the season with a high transfer rate (summer and fall), the stabling period (≤ 3 months), and age (2 to 3 years old), suggesting that the movement and new environment may have depressed the immune system of the horses and decreased their ability to respond properly to pathogens. The bacterial strains (n = 98) isolated from IURD horses included Pseudomonas spp., Escherichia coli, Staphylococcus spp., Streptococcus equi subsp. equi and zooepidemicus.     

Post-mortem re-cloning of a transgenic red fluorescent protein dog

Recently, the world''s first transgenic dogs were produced by somatic cell nuclear transfer. However, cellular senescence is a major limiting factor for producing more advanced transgenic dogs. To overcome this obstacle, we rejuvenated transgenic cells using a re-cloning technique. Fibroblasts from post-mortem red fluorescent protein (RFP) dog were reconstructed with in vivo matured oocytes and transferred into 10 surrogate dogs. One puppy was produced and confirmed as a re-cloned dog. Although the puppy was lost during birth, we successfully established a rejuvenated fibroblast cell line from this animal. The cell line was found to stably express RFP and is ready for additional genetic modification.     

Eggshell apex abnormalities associated with Mycoplasma synoviae infection in layers

Eggs exhibiting eggshell apex abnormalities (EAA) were evaluated for changes in shell characteristics such as strength, thickness, and ultrastructure. Mycoplasma synoviae (MS) infection was confirmed by serological assay along with isolation of MS from the trachea and oviduct. Changes in eggshell quality were shown to be statistically significant (p < 0.01). We also identified ultrastructural changes in the mammillary knob layer by Scanning Electron Microscopy. While eggs may seem to be structurally sound, ultrastructural evaluation showed that affected eggs do not regain their former quality. In our knowledge, this is the first report describing the occurrence of EAA in Korea.     

Polyhydroxyamic acid from 3,3′-dihydroxybenzidine and pyromellitic dianhydride as a fire-safe polymer

In order to assess the potential of the hydroxy-containing polyamic acid (PHAA) synthesized from 3,3′-dihydroxy benzidine and pyromellitic dianhydride for a fire-safe polymer, the cyclization pathway of PHAA has been investigated using a model compound prepared from 2-aminophenol and phthalic anhydride. The reaction was monitored by¹H-nuclear magnetic resonance. N-(2-hydroxyphenyl)phthalamic acid is converted to N-(2-hydroxyphenyl)phthalimide at ca. 175°C, showing endothermic reaction. The imide structure is rearranged to the benzoxazole structure over ca. 400°C. These results are similar with that of PHAA. According to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data, water and carbon dioxide are released during the cyclization and rearrangement reaction. One DMAc molecule is complexed with one carboxyl acid group in PHAA, which accelerates the imidization process to release more easily the flame retardant, water.     

The effect of compressional under-layer on muscle activity and exercise performance using EMG

The effect of functional under-layer on muscle activity and exercise performance was investigated on the basis of physiological tests and electromyography (EMG). EMG was used to study muscle activity during exercise after fitting compressional under-layer. We observed slight differences in the results of anaerobic and aerobic muscle EMG tests among subjects because of differences in body muscle content. In addition, muscle activity was varied according to muscle parts used during the physiological tests with fitting the functional under-layer. We suggest that compressional under-layer decreases muscle vibration and improves blood circulation, resulting in overall improved muscle activity on the basis of the usage of different muscles in each type of exercise. However, future studies are needed to evaluate the long-term effects of the functional under-layer.     

Effects of recycling processes on physical, mechanical and degradation properties of PET yarns

Mechanical properties and the long-term degradation properties of the recycled PET yarns are typically lower than the virgin PET yarns due to the contaminants coming from non-PET bottles, labels and caps etc. For environmental reasons, recycling of post-consumer polyester bottles into textile fibers has become commercially attractive. We studied mechanical and chemical recycling processes and examined their effects on yarn properties such as tensile properties, thermal characteristics, hydrolysis and photo-degradation. It was found that the virgin and the chemical recycled yarns with sufficient purification show similar processability, physical and mechanical properties, and long-term degradation behavior. The results provide useful information on recycled PET yarns for processability and serviceability for the high-end use.     

Hatching rate and larval growth variations in Pseudoplatystoma punctifer : maternal and paternal effects

In Pseudoplatystoma punctifer (e.g. Pseudoplatystoma fasciatum) larvae, parental effects on hatching, growth of initial stages and dry feed adaptation were evaluated as they could influence fry heterogeneity, which is responsible for the enhancement of cannibalism, and which remains one of the main factors of mortality during larval stages. A full factorial experiment was carried out with 3 females × 3 males producing nine families of full siblings, raised separately in triplicates into 30 L tanks at 28±0.5 °C in a water recirculating system. Paternal and maternal effects were observed on hatching success, yolk utilization efficiency and growth until 26 days post fertilization. Hatching success was generally over 80% except for one male × female combination (25%). Total length (TL) at hatching and during the first 4 weeks of exogenous feeding on live Artemia nauplii and dry feeds was determined in each family using digital photographs of larvae and nih image j analysis freeware. Mean TL was calculated for each family at each sampling time and analysed using multifactorial analysis of variance tests. These results indicate not only dam but also sire effects at very early developmental stages as well as in subsequent stages of P. punctifer.