Evaluation of a competitive ELISA for antibody detection against avian influenza virus

Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity.     

The effect of probiotic BioPlus 2B® on growth performance,dry matter and nitrogen digestibility and slurry noxious gas emission in growing pigs

For this study, 2 experiments were conducted to evaluate the effects of dietary BioPlus 2B^® supplements on growing pigs. In experiment 1, 64 crossbred pigs (26.70 ± 0.50 kg) were subjected to a 35-day feeding trial (2 pigs/pen, 8 pens/treatment) in which the effects of the following four corn-soybean meal based dietary treatments were compared: 1) CON (basal diet); 2) B0.05 (basal diet + 0.05% BioPlus 2B^®); 3) B0.1 (basal diet + 0.1% BioPlus 2B^®) and 4) B0.2 (basal diet + 0.2% BioPlus 2B^®). During the experimental period, average daily gain (ADG) tended to increase in a linear fashion (P = 0.08) with increasing levels of dietary BioPlus 2B^®. In addition, the average daily feed intake (ADFI) was found to increase (P < 0.05) as the levels of BioPlus 2B^® increased. However, no linear or quadratic effects were observed in the gain:feed ratio (G:F) or in the coefficients of total tract apparent digestibility (CTTAD) when dry matter (DM) and nitrogen (N) were considered. In experiment 2, 16 crossbred barrows (25.60 ± 0.10 kg) were randomly allotted to 1 of the 4 dietary treatments used in experiment 1 (1 pig/pen, 4 pens/treatment). The noxious gas emissions and pH of slurry waste were then measured daily for 120 h. Ammonia (NH₃) emission from the slurry samples obtained from pigs in the BioPlus 2B^® groups was lower than that of slurry obtained from pigs in the CON treatment (P < 0.05), however, hydrogen sulfide (H₂S) and mercaptan emission were not affected by supplementation with BioPlus 2B^®. In addition, the pH value decreased with time, and the pH values of slurry obtained from pigs subjected to the B0.1 and B0.2 treatments were lower than those of samples obtained from other groups after 48 h (P < 0.05). Taken together, these results indicate that supplementation with BioPlus 2B^® can reduce slurry NH₃ emission, but not H₂S and mercaptan emission in growing pigs without impacting growth performance.     

Silsesquiazane/organic polymer blends as organic-inorganic hybrid materials

Silsesquiazane (SSQZ), one of the branched forms of polysilazane, was blended with polystyrene (PS), poly(methyl methacrylate) (PMMA), poly(iso-butyl methacrylate) (PBMA), and poly(vinyl acetate) (PVAc) to produce organic-inorganic hybrid materials. The polymers were selected to provide specific interaction, such as ??-?? interaction or hydrogen bonding, with SSQZ. AFM studies revealed that carbonyl containing polymers, PMMA, PBMA, and PVAc were miscible with SSQZ while PS was immiscible. DSC analysis of the hybrids also supported the miscibility behaviours of the system. The glass transition behaviour of SSQZ/PS showed individual transition temperature corresponding to the each component while SSQZ/carbonyl-containing polymers displayed one transition temperature that matched with the theoretically calculated values following the Kwei equation. Among the miscible hybrid system, the interaction with SSQZ increased in the order of PMMA> PBMA> PVAc, as determined by the q value in the Kwei equation. This result was confirmed by determining the degree of hydrogen bonding in FT-IR spectra. Thermal stability of organic polymers was improved by incorporating SSQZ regardless of the miscibility.     

Physical and Milling Characteristics of Wheat Kernels After Enzyme and Acid Treatments

The current wheat milling process separates bran from endosperm by passing tempered wheat kernels through successive break rolls and sifters. Using hydrolytic enzymes during tempering degrades bran and aleurone layers and can improve milling efficiency and yield. This study was conducted to evaluate the effects of chemical and enzymatic treatments of wheat kernels before milling on physical and milling characteristics of the resulting wheat and flour quality. Hard wheat kernels were soaked in dilute acid or water and dried back to original moisture before being tempered with enzymes in water. Kernel physical and milling characteristics (600 g) were evaluated. Dilute acid soaking did not affect the 1,000‐kernel weight and diameter but softened treated kernels. When treated kernels were pearled, bran removal was mostly from ends; and the reducing sugar content in enzyme‐treated bran was significantly higher than the control. Compared with the control, acid‐soaked enzyme‐tempered kernels showed small but significant improvement in straight flour yield, with virtually no difference in protein content, and flour color. Chemical and enzyme treatment resulted in higher ash in flour. These differences were not seen in milling of larger batches (1,500 g) of kernels.     

Effects of Acetylsalicylic Acid and Calcium Chloride on Photosynthetic Apparatus and Reactive Oxygen-Scavenging Enzymes in Chrysanthemum Under Low Temperature Stress with Low Light

The effects of acetylsalicylic acid （ASA）, CaCl2, and ASA ＋ CaCl2 on the photosynthetic apparatus and antioxidant enzyme activities were investigated in chrysanthemum Jinba （a cut flower cultivar） under low temperature stress with low light （TL stress） （16/12℃, day/night, PFD 100 μmol m^-2 s-1）. The results showed that under TL stress, the net photosynthesis rate （Pn）, carboxylation efficiency （CE）, apparent quantum yield （AQY）, maximal photochemical efficiency （Fv/Fm） of PSII, quantum yield of PSII electron transport （ФPSII）, and photochemical quenching （qP） of the chrysanthemum leaves in all treatments were significantly decreased, but the decreases were alleviated by ASA, CaCl2, and ASA ＋ CaCl2 treatments compared with the controls. The alleviating effect of ASA ＋ CaCI2 was better than either ASA or CaCl2 single treatment. Moreover, the ASA ＋ CaCl2 treatment highly improved the chlorophyll content, relatively improved the number and size of chloroplast and starch grain in the leaves of chrysanthemum plants compared with ASA and CaCl2 treatments. It was indicated that ASA and/or CaCI2 could regulate the photosynthetic functions in the leaves of chrysanthemum plants to enhance the resistance against TL stress. On the other hand, reduction in relative conductance rate implied that ASA and/ or CaCl2 could protect from membrane injury in leaves of chrysanthemum plants. The activities of SOD, POD, and CAT in the treated leaves of chrysanthemum were increased as compared with the controls. It was suggested that ASA and/or CaCl2 had positive regulation effects on the defence enzyme activities in chrysanthemum leaves which could protect the photosynthetic apparatus to a certain degree under the TL stress. In brief, the treatment of ASA together with CaCl2 was better for chrysanthemum plants to adapt TL stress than single ASA or CaCl2 treatments.     

Outbreak of Brucellosis in Domestic Elk in Korea

Seven of 18 elk on a deer farm were found by the official Rose‐Bengal agglutination test (RBT) and tube agglutination test to be brucellosis reactors/suspects. Evaluation with the competitive ELISA (C‐ELISA) and the fluorescence polarization assay (FPA) tests revealed that six and five sera were positive respectively. The seven reactors/ suspects were slaughtered and their blood and tissues were collected. Brucella species could be isolated from three of the slaughtered animals, with nine isolates being obtained from the popliteal, supramammary and submandibular lymph nodes, vaginal discharge, mammary tissue and spleen. Brucella genus‐specific PCR based on 16S rRNA and AMOS‐PCR, which is specific for differential Brucella species, revealed that all nine isolates were Brucella abortus. These nine were further confirmed to be B. abortus biovar 1 by classical biotyping scheme assays. This is the first report of an outbreak of brucellosis in domestic elk in Korea. Our observations suggest that deer should be included in the routine Brucella surveillance programme for the effective control and prevention of brucellosis in Korea.     

Injection molding of vertebral fixed cage implant

A vertebral cage is a hollow medical device which is used in spine surgery. By implanting the cage into the spine column, it is possible to restore disc and relieve pressure on the nerve roots. Most cages have been made of titanium alloys but they detract the biocompatibility. Currently PEEK (polyether ether ketone) is applied to various implants because it has good properties like heat resistance, chemical resistance, strength, and especially biocompatibility. A new shape of vertebral cage is designed and injection molding of PEEK is considered for production. Before injection molding of the cage, it is needed to evaluate process conditions and properties of the final product. Variables affecting the shrinkage of the cage are considered, e.g., injection time, packing pressure, mold temperature, and melt temperature. By using the numerical simulation program, MOLDFLOW, several cases are studied. Data files obtained by MOLDFLOW analysis are used for stress analysis with ABAQUS, and shrinkage and residual stress fields are predicted. With these results, optimum process conditions are determined.     

Differential effects of treadmill exercise on calretinin immunoreactivity in type 2 diabetic rats in early and chronic diabetic stages

In this study, we investigated the effects of treadmill exercise on calretinin (CR), a marker of early postmitotic neurons, immunoreactivity in the dentate gyrus (DG) of Zucker diabetic fatty (ZDF) rats, before or after diabetes onset, and Zucker lean control (ZLC) rats. For this study, 6-week-old ZLC and prediabetic ZDF rats, and 22-week-old ZLC and ZDF rats were exercised on the treadmill. Sedentary ZLC and ZDF rats of the same age were used as exercise experiment controls. The exercised prediabetic ZDF rats did not show diabetes onset, while the sedentary prediabetic ZDF rats showed significantly increased blood glucose levels. The exercised diabetic ZDF rats exhibited a decrease in their blood glucose levels compared to the sedentary diabetic ZDF rats, but the levels were still above 20 mmol/l. ZLC rats of both ages were in the normoglycemic range. CR immunoreactivity was detected throughout the DG, including the subgranular zone and the polymorphic layer. Diabetic rats exhibited a significant decrease in the number of CR-immunoreactive cells and fibers in the DG. Exercise in the prediabetic ZDF rats significantly increased the number of CR-immunoreactive cells and fibers in the subgranular zone of the DG. In the ZLC and ZDF rats of chronic diabetic phase, exercise increased CR-immunoreactive neurons in the hilar region. These results suggest that diabetes significantly reduces the number of postmitotic CR-immunoreactive neurons and the intensity of immunoreactivity and that exercise increases these CR-related parameters in a diabetic stage-dependent manner.