Mesh selectivity of encircling gill net for gizzard shad Konosirus punctatus in the coastal sea of Korea

ABSTRACT:   Fishing experiments were carried out in Yeongil Bay, Korea using an encircling gill net with four different mesh sizes and two different hanging ratios to measure the mesh selectivity for gizzard shad Konosirus punctatus . Twenty-six trials were conducted giving a total catch of 485 gizzard shad. The 'share each length's catch total' (SELECT) analysis with maximum likelihood method was used to fit the different functional models, the normal, lognormal, and bi-normal model, for a selectivity curve to the catch data. In addition, two cases in which the relative fishing intensity was either estimated or fixed were compared. The bi-normal model with the fixed relative fishing intensity was found to fit the data best. For the selectivity curve on the bi-normal model, the relative length (the ratio of fish length to mesh size) with the maximum efficiency was obtained as 3.70. From this, the focal fish lengths in the commercial encircling gill net, with mesh size ranging from 5.0 to 6.0 cm, were inferred to be 18.5–22.2 cm.     

Efficacy and safety of allogenic canine adipose tissue-derived mesenchymal stem cell therapy for insulin-dependent diabetes mellitus in four dogs: A pilot study

Mesenchymal stem cells (MSCs) possess regenerative and immunomodulatory properties and can control the immune dysregulation that leads to β-cell destruction. Stem-cell transplantation could thus manage insulin-dependent diabetes mellitus (IDDM) in dogs. In this pilot study, we aimed to assess canine adipose tissue-derived MSCs (cAT-MSCs) transplantation as a treatment for canine diabetes mellitus. This study included four dogs with over a year of insulin treatment for IDDM, following diagnosis at the Veterinary Medicine Teaching Hospital of Seoul National University. Allogenic cAT-MSCs were infused intravenously three or five times monthly to dogs with IDDM. Blood and urine samples were obtained monthly. General clinical symptoms, including changes in body weight, vitality, appetite, and water intake were assessed. Three of the four owners observed improvement of vitality after stem cell treatment. Two of the four dogs showed improvement in appetite and body weight, polyuria, and polydipsia. C-peptide has increased by about 5–15% in three of the cases, and fructosamine and HbA1c levels have improved in two of the cases. Hyperlipidemia was resolved in two of the dogs, and there was no concurrent bacterial cystitis in any of the dogs. C-peptide secretion and lipid metabolism are associated with diabetic complications. Improvement in these parameters following the treatment suggests that cAT-MSC transplantation in dogs with IDDM might help to improve their insulin secretory capacity and prevent diabetic complications.     

Effect of 7,8-Dihydroxyflavone as an Antioxidant on In Vitro Maturation of Oocytes and Development of Parthenogenetic Embryos in Pigs

One of the factors that impairs in vitro produced porcine embryos is the oxidative stress that is mainly caused by the imbalance between reactive oxygen species (ROS) generation and antioxidants activity, especially that of glutathione (GSH). Here, we examined the effect of 7,8-dihydroxyflavone (7,8-DHF), a kind of flavonoid antioxidant, on porcine oocyte maturation and its developmental competence. Porcine oocytes were cultured in media supplemented with 0, 1, 5 and 10 μM 7,8-DHF during both in vitro maturation (IVM) and in vitro culture (IVC) after parthenogenetic activation. Maturation of oocytes was evaluated based on first polar body (PB) extrusion and intracellular GSH level, and developmental competence was assessed through observing cleavage and blastocyst formation. In each step, the levels of intracellular GSH and ROS were assessed by fluorescence intensity, and the apoptosis-related gene expression was examined using semiquantitative RT-PCR. The group treated with 1 μM 7,8-DHF during IVM and IVC showed increased cytoplasmic maturation and reached the blastocysts stage (36.1%) at a higher rate than the other groups (24.7, 16.0 and 10.3% for 0, 5 and 10 μM, P<0.05). In that group, the intracellular GSH level was significantly increased while ROS generation was significantly decreased after IVM and IVC (P<0.05). Moreover, it showed high expression of an anti-apoptotic gene (BCL2L1) and low expression of a pro-apoptotic gene (BAK1) (P<0.05). In conclusion, treatment with 1 μM 7,8-DHF during IVM and IVC showed an anti-apoptotic effect by increasing intracellular GSH synthesis and scavenging ROS and therefore improved the developmental competence of porcine embryos.     

Effect of Ethylene Treatment on Kiwifruit Bioactivity

The consumption of fruits and vegetables with high antioxidant activities leads to best healthful results. Therefore, in the present investigation we tried to find the peak of the kiwifruits antioxidant activity during the first 10 days of ethylene treatment (100 ppm at 20 °C).In order to receive the most reliable data five different antioxidant assays were used: ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC); trolox equivalent antioxidant capacity (TEAC); 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH); and Folin-Ciocalteau. It was found by all applied methods that kiwifruit samples have the highest contents of polyphenols and flavonoids and the highest antioxidant activity on the 6-th day of the ethylene treatment. The correlation coefficients between polyphenols, flavonoids and antioxidant activities of kiwifruit methanol extracts with TEAC and CUPRAC, were as followed: 0.81 and 0.63, and 0.23 and 0.17, respectively, and showed that the free polyphenols correlation coefficients were higher than that of the flavonoids.In conclusion: during ethylene treatment the bioactivity of kiwifruit is increasing and reaches its maximum at the 6th day and therefore it is the optimum time for kiwifruit consumption; total polyphenols were the main contributor to the overall antioxidant activity of kiwifruit; the most sensitive test for antioxidant activities determination is FRAP.     

Pharmacokinetics and pharmacokinetic/pharmacodynamic integration of orbifloxacin in Korean Hanwoo cattle

The pharmacokinetics and pharmacodynamics of orbifloxacin were studied in six clinically healthy Hanwoo cows after intravenous (i.v.) and intramuscular (i.m.) administration at a dose of 3 mg/kg. Orbifloxacin concentrations were determined by high performance liquid chromatography with fluorescence detection. Steady-state volume of distribution and clearance of orbifloxacin after i.v. administration were 0.92 L/kg and 0.24 L/h·kg, respectively. Following i.m. administration, a slow and complete absorption with absolute bioavailability of 101.4%, and a maximum concentration ( C _max) of 1.17 μg/mL at 1.04 h were observed. The in vitro serum protein binding was 14.76%. The in vitro antibacterial activity of orbifloxacin against a pathogenic strain of Mannheimia haemolytica ( M. haemolytica ), Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) was determined . The ex vivo activity of orbifloxacin against M. haemolytica strain was also determined , and these data were integrated with the ex vivo bacterial counts to establish AUC _24h/ MIC values producing bacteriostatic action, bactericidal action and elimination of bacteria. Mean values were 32.7, 51.6 and 102.6 h, respectively. From these data, we predict that orbifloxacin, when administered i.m. at a dosage of 2.5–5 mg/kg once a day, would be effective against bovine pathogens, such as M. haemolytica. Additional studies may be needed to confirm its efficacy in a clinical setting, and to evaluate the penetration of the drug in diseased tissues.     

模拟增温和降水调控对土壤微生物碳氮、群落基质利用模式及群落组成的短期影响

Soil microorganisms are major drivers of soil carbon(C) cycling;however,the response of these microorganisms to climate change remains unclear.In the present study,we investigated how 18 months of multifactor climate treatments(warmed air temperature by 3℃ and decreased or increased precipitation manipulation by 30%) affected soil microbial biomass C and nitrogen(N),community substrate utilization patterns,and community composition.Decreased and increased precipitation significantly reduced microbial biomass C by 13.5% and 24.9% and microbial biomass N by 22.9% and 17.6% in unwarmed plots,respectively(P0.01).Warming enhanced community substrate utilization by 89.8%,20.4%,and 141.4% in the natural,decreased,and increased precipitation plots,respectively.Particularly,warming significantly enhanced the utilization of amine and carboxylic acid substrates among all precipitation manipulation plots.Compared with the natural air temperature with natural precipitation treatment,other treatments affected fungal community richness by -0.9% to 33.6% and reduced the relative abundance of the dominant bacterial and fungal groups by 0.5% to 6.8% and 4.3% to 10.7%,respectively.The warming and/or precipitation manipulation treatments significantly altered Zygomycota abundance(P0.05).Our results indicate that climate change drivers and their interactions may cause changes in soil microbial biomass C and N,community substrate utilization patterns,and community composition,particularly for the fungal community,and shifts in the microorganism community may further shape the ecosystems function.     

COMPARISON OF GROSS AND HISTOPATHOLOGIC FINDINGS WITH QUANTITATIVE COMPUTED TOMOGRAPHIC BONE DENSITY IN THE DISTAL THIRD METACARPAL BONE OF RACEHORSES

Comparison of subchondral bone density determined by quantitative computed tomography (CT) with gross and histopathologic changes have not been made in horses. The goal of this study was to determine if mean quantitative CT density and mean voxel standard deviation are associated with the presence and severity of osteochondral lesions in the palmar aspect of the distal third metacarpal bone in racing horses. Metacarpophalangeal joints from nine racehorses were imaged using CT and scored for gross damage. Four-millimeter-thick sagittal and 30 degrees palmar dorsal plane sections were cut, decalcified and stained with hematoxylin and eosin from the distal third metacarpal bone. Microscopic osteochondral lesions and subchondral remodeling were scored on a scale of 0-3. Percent subchondral bone, expressed as the ratio of bone volume to tissue volume, was also measured. Mean quantitative CT density and mean voxel standard deviation were measured from three-dimensional models of CT images comparable with histologic sections. Mean quantitative CT density was not associated with lesion severity or number of lesions. A weak correlation between mean quantitative CT density and gross score was found, but mean quantitative CT density was not predictive for gross score. Mean voxel standard deviation was not correlated with gross or histopathologic measures, but was predictive of mild osteochondral lesions. Results support the association of subchondral remodeling with the development of palmar metacarpal lesions. However, there was not a strong correlation between mean quantitative CT density or mean voxel standard deviation and histopathologic lesions of the distal third metacarpal bone.