Temperature-dependent index of mitotic interval τ0 in greenling Hexagrammos otakii

ABSTRACT:   The aim of this study was to establish effective procedures for chromosome manipulation in greenling Hexagrammos otakii Jordan et Starks, which has enormous aquacultural potential. To accomplish this, temperature-dependent measurements of the mitotic intervals (τ₀) were carried out. The τ₀ in this fish was determined by averaging the duration of the first and third embryonic divisions at temperatures ranging 5–25°C. At higher temperatures, eggs developed faster and underwent more identical development. For greenling, τ₀ were 341.1 ± 3.60 min at 5°C, 275.5 ± 4.53 min at 10°C, 189.7 ± 6.93 min at 15°C, 99.2 ± 8.27 min at 20°C and 34.2 ± 8.74 min at 25°C. There were strong, negative correlations between the τ₀ and water temperatures at all temperatures studied ( Y  = −79.3 X  + 425.3, R ² = 0.9968, where Y is the mitotic interval and X is the temperature).     

Appearance of Infectious Hematopoietic Necrosis Virus in Rainbow Trout,Oncorhynchus mykiss,During Seawater Adaptation

About 7% mortality occurred in rainbow trout, Oncorhynchus mykiss, during seawater adaptation at a marine farm in the South Sea of Korea during the winter of 2014. Most diseased fish showed petechial hemorrhaging of gills and internal fat with enlarged spleen. Although no parasites or bacteria were isolated from the diseased fish, all tissue filtrates produced cytopathic effects (CPEs) in fathead minnow and Chinook salmon embryo‐214 cells. The cell culture supernatant showing CPE contained specific 1527‐bp fragment for the infectious hematopoietic necrosis virus (IHNV) glycoprotein gene by polymerase chain reaction. Their nucleotide sequences shared 98.1–98.2% identities with IHNV RtUi02 isolated from rainbow trout in Korea. This isolate (RtGoH14) was closely related to Korean IHNV isolates of genogroup JRt rather than to those of North American and European genogroups. These results suggest that this IHNV isolate might have been introduced to rainbow trout farm (land‐based culture system) in Korea. This is the first report of IHNV infection in rainbow trout during seawater adaptation in Korea.     

Proliferation of kuchijirosho causative agent in a fugu-derived cell line

Kuchijirosho is a fatal disease of commercially cultured fugu, Takifugu rubripes. The transmissible nature of kuchijirosho strongly suggests that an infectious pathogen is the causative agent. Because it is filtrable, the agent is thought to be a virus; however, it has not yet been identified. The lack of a permissive cell line for the putative kuchijirosho-causing agent (KCA) has hindered research on the identification of this pathogen. We inoculated brain extract prepared from kuchijirosho-affected fugu onto an established fugu cell line, fugu eye, and observed that cytopathic effect appeared 7 days after inoculation. Injection of the culture medium of infected fugu eye cells into fugu resulted in the onset of kuchijirosho, indicating that fugu eye cells are able to proliferate KCA. An infectious fraction separated by sodium iottalamate density gradient centrifugation showed a density of 1.15 g mL(-1) equivalent to that of KCA derived from affected fugu brain. To determine whether the genome of KCA is RNA or DNA based, nucleotide synthesis inhibitors were applied to inoculated fugu eye cell line to influence the production of KCA. 5-Fluorouracil but not IUdR showed a concentration-dependent inhibition of KCA yield. These results suggest that KCA is an RNA virus.     

Curcuma longa L. constituents inhibit sortase A and Staphylococcus aureus cell adhesion to fibronectin

The inhibitory activity of Curcuma longa L. (turmeric) rhizome constituents against sortase A, a bacterial surface protein anchoring transpeptidase, from Staphylococcus aureus ATCC 6538p was evaluated. The activity of the isolated compounds (1-4) was compared to that of the positive control,p-hydroxymecuribenzoic acid (pHMB). The biologically active components of C. longa rhizome were characterized by spectroscopic analysis as the curcuminoids curcumin (1), demethoxycurcumin (2), and bisdemethoxycurcumin (3). Curcumin was a potent inhibitor of sortase A, with an IC50 value of 13.8 +/- 0.7 microg/mL. Bisdemethoxycurcumin (IC50 = 31.9 +/- 1.2 microg/mL) and demethoxycurcumin (IC50 = 23.8 +/- 0.6 microg/mL) were more effective than pHMB (IC50 = 40.6 +/- 1.2 microg/mL). The three isolated compounds (1-3) showed no growth inhibitory activity against S. aureus strain Newman, with minimum inhibitory concentrations (MICs) greater than 200 microg/mL. Curcumin also exhibited potent inhibitory activity against S. aureus cell adhesion to fibronectin. The suppression of fibronectin-binding activity by curcumin highlights its potential for the treatment of S. aureus infections via inhibition of sortase activity. These results indicate that curcumin is a possible candidate in the development of a bacterial sortase A inhibitor.     

Phytophthora ramorum Colonizes Tanoak Xylem and Is Associated with Reduced Stem Water Transport

ABSTRACT Isolation, detection with diagnostic polymerase chain reaction (PCR), and microscopy demonstrated the presence of Phytophthora ramorum in the sapwood of mature, naturally infected tanoak (Lithocarpus densiflorus) trees. The pathogen was strongly associated with discolored sapwood (P < 0.001), and was recovered or detected from 83% of discolored sapwood tissue samples. Hyphae were abundant in the xylem vessels, ray parenchyma, and fiber tracheids. Chlamydospores were observed in the vessels. Studies of log inoculation indicated that P. ramorum readily colonized sapwood from inoculum placed in the bark, cambium, or sapwood. After 8 weeks, radial spread of P. ramorum in sapwood averaged 3.0 to 3.3 cm and axial spread averaged 12.4 to 18.8 cm. A field study was conducted to determine if trees with infected xylem had reduced sap flux and reduced specific conductivity relative to noninfected control trees. Sap flux was monitored with heat-diffusion sensors and tissue samples near the sensors were subsequently tested for P. ramorum. Adjacent wood sections were excised and specific conductivity measured. Both midday sap flux and specific conductivity were significantly reduced in infected trees versus noninfected control trees. Vessel diameter distributions did not differ significantly among the two treatments, but tyloses were more abundant in infected than in noninfected trees. Implications for pathogenesis, symptomology, and epidemiology are discussed.     

Effect of pH Conditions on Actual and Apparent Fluoride Adsorption by Biochar in Aqueous Phase

Biochar is a carbon-rich product derived from biomass through pyrolysis. Fluoride adsorption potential of the biochar derived from orange peel (OP) and water treatment sludge (WS) at different pyrolytic temperatures (400, 600, and 700?°C) was investigated in a batch mode as a function of pH. With respect to adsorption, two types were considered, i.e., actual and apparent adsorption where fluoride combined with metal complexes in solution were counted and not counted, respectively. The highest actual fluoride adsorption was observed in the pH range of 2.0 to 3.9 for OP biochar and 5.1 to 6.2 for WS biochar, respectively. For the WS biochar, apparent fluoride adsorption showed nearly 100?% in the pH range of 2.0 to 4.5, and then the adsorption capacity diminished drastically as the pH increased from 5.0 to 10.0. There was no significant difference between apparent and actual fluoride adsorption for OP biochar. In the Fourier-transform infrared spectroscopic analysis of WS biochar, a strong and sharp band was observed at around 2,364?cm^?1 after adsorption of fluoride. Elemental content analysis by the energy-dispersive X-ray method revealed that the fluorine content was higher at pH 6.0 than at pH 3.0 and 9.0 as the results of actual fluoride adsorption. From these results, we may conclude that the biochar derived from OP and WS can be reused as an economical and effective adsorbent for fluoride removal in acidic aqueous phase.     

Image analysis: A novel technique to determine the efficiency of wiping cloths

The ability to absorb liquid and the dust removal performance are important factors for wiping cloths used to remove contaminants. We have developed a method that can determine the contaminant removal performance of wiping cloths. In the gravimetric method, experimental errors are unavoidable because the contaminant plate is much heavier than the contaminant material. However, we used image analysis to reduce the experimental errors, and did not use the heavy contaminant plate. The correlation coefficient between the image analysis and the gravimetric methods was very high, at R=0.97, with a significance level of 95 %. From the correlation analysis and empirical data, the image analysis method is a useful tool for measuring wiping efficiency. The wiping efficiency measured using image analysis has a close relationship to the wiping speed, viscosity of the contaminant, and wiping pressure, at the significance level of 95 %.     

Neurotrophic protein regulates muscle acetylcholinesterase in culture

Skeletal muscles lose acetylcholinesterase in culture as a result of denervation. A protein fraction isolated from peripheral nerves maintained the level of acetylcholinesterase in cultures of aneural embryonic muscle or denervated adult chicken muscle. These results indicate that trophic regulation of muscle acetylcholinesterase might be mediated by a protein produced by nerves.     

Fucoxanthin Suppresses Osteoclastogenesis via Modulation of MAP Kinase and Nrf2 Signaling

Fucoxanthin (FX), a natural carotenoid present in edible brown seaweed, is known for its therapeutic potential in various diseases, including bone disease. However, its underlying regulatory mechanisms in osteoclastogenesis remain unclear. In this study, we investigated the effect of FX on osteoclast differentiation and its regulatory signaling pathway. In vitro studies were performed using osteoclast-like RAW264.7 cells stimulated with the soluble receptor activator of nuclear factor-κB ligand or tumor necrosis factor-alpha/interleukin-6. FX treatment significantly inhibited osteoclast differentiation and bone resorption ability, and downregulated the expression of osteoclast-specific markers such as nuclear factor of activated T cells 1, dendritic cell-specific seven transmembrane protein, and matrix metallopeptidase 9. Intracellular signaling pathway analysis revealed that FX specifically decreased the activation of the extracellular signal-regulated kinase and p38 kinase, and increased the nuclear translocation of phosphonuclear factor erythroid 2-related factor 2 (Nrf2). Our results suggest that FX regulates the expression of mitogen-activated protein kinases and Nrf2. Therefore, FX is a potential therapeutic agent for osteoclast-related skeletal disorders including osteoporosis and rheumatoid arthritis.