Disinfectant-filled footbaths are the most commonly used infection control measures on livestock farms. The purpose of this study was to evaluate the efficacy of six commercial disinfectants, as used in footbaths on farms, for reducing Salmonella Typhimurium contamination of footwear. When used at the recommended concentrations, most disinfectants showed over 91% reduction efficacy in absence of organic matter. The greatest reductions were seen with oxidizing agents including potassium peroxymonosulfate-based products and sodium dichloroisocyanurate. These results suggest that disinfectant footbaths could be useful for reducing bacteria; however, footbaths should not be relied upon as the only method of controlling infectious pathogens. General good hygiene practice, for example cleanliness of boots, should be emphasized.
The interest in convenience food has increased over the years. Many researchers have tried to discover what factors affect the consumption of convenience food. Despite the diversity of studies, few studies emphasize a household’s income. The aim of this article is to identify the different consumption patterns between upper, middle, and lower income brackets. Generally, households with higher income consumed more convenience food or the relationship was not significant. However, many convenience foods are regarded as nutritionally unbalanced and have a lower quality. So, the hypothesis cannot be easily confirmed because there are tradeoffs not only between health, as nutrition balance and cost, but also health and convenience. Thus, there is a need to indicate the divergent attributes of buying convenience food in a distinct income group. In addition, the convenience food is subdivided into two distinct categories: convenience food as a substitution for a whole meal (unhealthy) and substitution as part of a diet (healthy). We found that higher income groups purchase healthier convenience food while lower income groups purchase unhealthier convenience food. Also there are distinct attributes that influence the consumption of healthy and unhealthy convenience food.
Determining the infection history of living organisms is essential for understanding the evolution of infection agents with their host, particularly for key aspects such as immunity. Viruses, which can spread between individuals and often cause disease, have been widely examined. The increasing availability of fish genome sequences has provided specific insights into the diversity and host distribution of retroviruses in fish. The shortspine spurdog (Squalus mitsukurii ) is an important elasmobranch species; this medium-sized dogfish typically lives at depths of 100~500 m. However, the retroviral envelope polyprotein in dogfish has not been examined. Thus, the aim of the present study was to identify and analyze the retroviral envelope polyprotein in various tissues of dogfish. The 1334-base pair full-length novel cDNA of dogfish envelope polyprotein (dEnv) was obtained by 3' and 5'-rapid amplification of cDNA end analysis from S. mitsukurii. The open reading frame showed a complete coding sequence of 815 base pairs with a deduced peptide sequence of 183 amino acids that exhibited 34~50% identity with other fish and bird species. It was also expressed according to reverse transcription and real-time polymerase chain reaction in the kidney, liver, intestine, and lung, but not in the gill. This distribution can be assessed by identifying and analyzing endogenous retroviruses in fish, which consists of three main genes: gag, pol and env. Dogfish envelope polyprotein sequence is likely important in evolution and induces rearrangements, altering the regulatory and coding sequences. This is the first report of the identification and molecular characterization of retroviral envelope polyprotein in various tissues of S. mitsukurii.
Human interferon alpha 2b (hIFNα-2b) is an important immune regulator widely used in clinic, for the treatment of chronic hepatitis, hairy cell leukemia, chronic myelogenous leukemia and multiple myeloma, etc. The clinically used hIFNα-2b is generally produced by E. Coli, which lacks the post-translational O-glycosylation of naturally synthesized protein, and has a short serum half-life. In this study, we report the successful generation of transgenic chickens that produce hIFNα-2b in the egg white using a feline immunodeficiency virus (FIV)-based lentiviral vector. In preliminary in vitro study, the hIFNα-2b gene under the control of CMV promoter expressed as much as 2,650 ng/㎖ in CEF-LNC-hIFNα-2bW cell. A FIV vector packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected underneath the blastoderm of freshly laid chicken eggs (stage X) to produce a hIFNα -2b transgenic chicken. Out of 187 injected eggs, 55 chicks were hatched after 21 days of incubation, and 27 of the G0 hatched chicks expressed the vector-encoded hIFNα-2b gene. The expression of recombinant hIFNα-2b in transgenic chickens constitutes an important step towards low-cost and full biological activity production of this protein drug in bioreactor.
This work was supported by the Bio-industry Technology Development Program, Ministry of Agriculture, Food and Rural Affairs, Republic of Korea, and by a grant from the Next-Generation BioGreen 21 Program (No. PJ011178), Rural Development Administration, Republic of Korea.
In the present study, using a MoMLV-based retrovirus vector, we successfully generated a new transgenic chicken line expressing high levels of hEPO. A replication-defective Moloney murine leukemia virus (MoMLV)-based vectors packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected beneath the blastoderm of non-incubated chicken embryos (stage X). One rooster was mated to wild-type hens to produce 748 G1 progeny. PCR analysis of blood samples from these progeny revealed that there were seven G1 transgenic offspring, corresponding to a 0.9% germline transmission rate. Subsequently, Southern blot analysis of the genomic DNA from three G1 transgenic chickens was carried out to verify the stable genomic integration and copy number of the transgene in the genome. Quantitative analyses of the blood samples taken from G1 transgenic chickens resulted in 4,150 ~ 10,823 IU/㎖ (34.6 ~ 90.2 ㎍/㎖) of hEPO in the blood. The biological activity of the recombinant hEPO in transgenic chicken serum was comparable to its commercially available counterpart. Red blood cell numbers were more than three-fold higher in the transgenic chickens compared to the non-transgenic chickens. Successful germline transmission of the transgene was also confirmed in G2 transgenic chicks produced from crossing G1 transgenic roosters with non-transgenic hens. We confirmed that 13 transgenic chicks of 45 G2 progeny, corresponding to a 28.9% germline transmission rate. These results will help establish a useful transgenic chicken model system for studies of embryonic development and for efficient production of transgenic chickens as bioreactors.
This work was supported by the Bio-industry Technology Development Program, Ministry of Agriculture, Food and Rural Affairs, Republic of Korea, and by a grant from the Next-Generation BioGreen 21 Program (No. PJ011178), Rural Development Administration, Republic of Korea.
Abnormal epigenetic reprogramming of donor nuclei is supposed to be one of the factors that causes low development efficiency of mammalian somatic cell nuclear transfer (SCNT). Trichostatin A (TSA) is an inhibitor of histone acetylase, and so development of SCNT embryos could be increased by treatment with TSA. In the present study, we examined the effect of TSA on in vitro development of porcine embryos derived from NT (nuclear transfer) by investigating the status of histone acetylation in TSA-treated and control NT embryos and the expression of developmental related genes.
In this study, we found that incubating NT embryos with 40nM TSA for 24h after activation could improved the blastocyst formation rate from 13.7% to 32.5%. Thechange in histone acetylation level as a reslut of TSA treatment were validated using immunofluorescence and confocal microscopy.
Immunofluorescence results indicated that the level of aetylation at histone 3 lysine 18 (AcH3K18) was increased at early embryo development stage after TSA treatment. furthermore, we compared the expression patterns of several genes (developmental related genes; Oct4, Sox2, Nanog, Cdx2, the imprinting genes; igf2r). TSA treatment improved the expression of development related genes such as Oct4, Cdx2, Nanog as well as the imprinted genes like igf2r.
In conclusion, our results demonstrated that TSA treatment improves the in vitro development of porcine NT embryos, increased the global histone acetylation (AcH3K18) and enhances the expression of some developmentally important genes (Oct4, Cdx2, Nanog) at blastocyst stages.
Due to their anatomical, physiological and genetic similarities, pig is attractive animal model in biomedical research. In the recent stem cell research era, porcine derived stem cells also gain attention due to its use for the preclinical application of human.
Mesenchymal stem cells (MSCs) have been studied by many researchers over decade, and their prospect for clinical application is recognized. Although porcine derived MSCs (pMSCs) have confirmed to be differentiated into various types of cells, such as osteocyte, chondrocyte, neuronal cell, cardiomyocyte and pancreatic β cell, few report has been studied regarding hepatocyte differentiation in vitro. The present study was therefore aimed for bone marrow MSCs derived from pig femur to differentiate into hepatocyte. The cells were confirmed as MSCs by characterizing their morphology, lineage differentiation capacity and surface phenotype. They showed spindle like morphology and adipocytic, osteoblastic, and chondrocytic differentiation potentials and displayed positive expression of mesenchymal markers CD29, CD44 and CD90 while lacked the expression of hematopoietic marker CD45. Under appropriate differentiation conditions, MSCs displayed hepatocyte-like morphology depending on duration of differentiation. The differentiated MSCs into hepatocyte expressed hepatocyte-specific genes including hepatocyte nuclear factor 4 (HNF4), albumin (ALB), alpha fetoprotein (AFP), alpha-1-anti trypsin (A1AT). They also showed hepatocyte-like function, glycogen storage which is identified by PAS staining. Taken together, it concluded that the bone marrow MSCs have the potential to differentiate into hepatocyte. Further studies are needed on additional hepatocytic functional assays, such as low density lipoprotein (LDL) uptake and urea synthesis of differentiated MSC.
Increase of bovine embryos produced by in vitro fertilization (IVF) has been seen. The main reason for producing in vitro fertilized embryos in Korea has been to utilize the genetics of cows with higher carcass grade. Ovaries are collected from the cows in the slaughter house and the information on the carcass grade of the cow can be traced. Embryos produced from cows with higher carcass grade have been favored by the farmers. PCR has been one of the main techniques for sex determination of embryos targeting various genes. Bovine sex determining region Y (SRY) is specific to Y chromosome. However, it requires a control gene for PCR, if the embryo is female. In comparison to SRY, amelogenin can be amplified from male or female embryos with different fragment sizes due to differential splicing in all bovidae. The goal of this study was to determine whether there are any differences in the sex ratio of embryos produced in vitro and to compare the efficiency of sex determination using PCR. Ovaries of Hanwoo were collected and transported to the laboratory in thermal bottles. For in vitro maturation, oocytes were collected from the follicles with less than 8 mm of diameter and placed in either the Brackett & Oliphant media (BO), Tissue culture medium-199 (TCM-199), or IVMD101 media, containing 3% fetal bovine serum (FBS), 0.5 mg/ml FSH, 0.5 mg/ml LH, and 1 mg/ml estradiol-17β. For IVF, frozen sperm from Hanwoo bulls were used. After 22-24h IVF, embryos were transferred and cultured either in BO or TCM-199 with 10% FBS until the embryos were hatched. Hatched blastocysts were stored in PBS frozen, and later thawed and treated with embryo lysis buffer. After isolating genomic DNA, it was used for PCR using primers for casein beta (CSN2), as PCR control, or for male specific SRY primers. Alternatively, primers for amelogenin were used. Sex of embryos was determined and the sex ratio was analyzed. Out of 94 embryos, sex of 83 embryos (88.3%) was determined and there were 40 male embryos (48.2%) and 43 female embryos (51.8%). Sex of 31 embryos was determined using both SRY and amelogenin. Among those, 17 embryos were determined as having identical sex, while 1 embryo was determined as having different sex, and the sex of 11 and 2 embryos were determined only by amelogenin or SRY primers, respectively. In conclusion, the success of determining the sex of embryos by PCR was relatively high. Using amelogenin primer for PCR tends to be more efficient than SRY primer in determining the sex. Slightly higher ratio of female embryos was different from previous years and the cause for the difference may require further investigation.
The soybean aphid, Aphis glycines Matsumura, was introduced from East Asia (EA) into North America (NA) and is now widely established in NA. To compare soybean aphid populations between the native and invasive regions, we examined 689 individuals obtained from 28 different collections in NA and EA. A total of 8 microsatellite loci were used for population genetics statistics. Gene diversity and mean number of alleles in NA populations averaged 0.40 and 2.70, respectively, whereas in EA they averaged 0.55 and 4.32, respectively. Structure analysis of all populations revealed two distinct structures in the invaded and in the native regions. Among EA populations, certain Korean populations were genetically closest to NA populations, especially those from Ohio and Delaware. An approximate Bayesian computation test also supports an introduction into NA from Korea.
Non-target predatory insects can be indirectly exposed to aerial pesticide spraying and fogging to control Monochmus beetles that transmit pine wood nematode, Bursaphelenchus xylophilus. We evaluated potential lethal or sublethal effects of thiacloprid on survival and behavior of a carpenter ant species, Camponotus japonicus Mayr. Field-collected ant colonies were directly exposed to several food items, such as thiacloprid-addicted Monochmus beetles, 10% sugar watered cotton balls contaminated by thiacloprid concentrations, and 10% sugar water. Dead beetle bodies caused no apparent adverse effect through dietary exposure in general, although a few ants were died with paralysis at colony level experiment. At individual level, most ant workers were died within 10 days compared to control group. In contrast, dietary exposure of ants to thiacloprid concentrations showed significant lethal effect with paralysis and impaired walking, especially at 10 and 50 mg/L thiacloprid concentrations. Some intoxicated ants recovered within a few days in 10 and 50 mg/L thiacloprid concentrations, but intoxicated ants were generally shown to be less responsible to enemy ants with low aggressive behavior. Implications for predicting hazards of thiacloprid to beneficial arthropods in pine forests are discussed.
The population size of Red-spotted Apollo Butterfly(Parnassius bremeri) has been reduced because of their habitats destruction and partly climate change. Estimation of metapopulation size and survival day of Red-spotted Apollo Butterfly was made in Samcheok where release was carried for 5 years, Korea, by using the mark-release-recapture method. 421(female: 188, male: 233) of Red-spotted Apollo Butterfly were captured and 177 individuals(female: 89, male: 88) were recaptured and rates of recapture was 42%. Average of survival day was 3.59 and max survival day was 11. The migration of Red-spotted Apollo Butterfly was occurred significantly between short patches. Their max distance of migration was 6.74km. Estimate of P. bremeri was from minimum 125 to maximum 1844.
Vollenhovia emeryi (Formicidae: Myrmicinae) is divided into two morphs based on the wing length of the queen caste: the long-winged with a normal wing and the short-winged with the aberrant short wing. The phylogenetic analysis shows that the short-winged is derived from the long-winged. In Korea, only the long-winged morph is infected with Wolbachia while the short-winged is devoid of the bacterium suggesting that the short-winged evolved the resistance to the bacterial infection. Intriguingly, some Japanese short-winged colonies proved to still be infected with the bacterium.
We hypothesized that the infected Japanese short-winged is the intermediate form in the process to complete cure. However, the data of the MLST and the measurement of Wolbachia density did not support our hypothesis. Our further experiment using microsatellite markers shows that the infected Japanese short-winged shows the similar genetic background to the long-winged. In this presentation we will discuss the potential resistance evolution in the Korean short-winged and future research direction at the genome level.
White rice with grains is a nutritious meal that richly contains fiber, vitamin and mineral, but it is difficult for elderly people to masticate some grains and beans due to its hardness. This study was aimed to find the optimal mixing ratio of rice with texture modified grains and beans by comparing rheological properties. Beans were soaked in tap water for 24 hr at 20°C, cooked under pressure (1hr at 121°C), frozen for 24 hr at -18°C, and thawed in water bath for three hr at 30°C. The samples were submerged in macerating enzyme solution, left under vacuum at 60 mmHg for 5 min to infuse the enzyme into the intercellular spaces of samples, and rapidly returned to the atmospheric pressure. The samples were removed from enzyme solution, sealed in plastic bag, placed at 70°C for 20 min for enzyme activation and inactivated at 95°C for 15 min. The grains and texture modified beans were added to white rice with different ratio, soaked for one hr in enzyme solution under warming condition at 70°C, and steamed with electric pressure cooker. Cooked meals were rapidly cooled at -18°C for one hr, placed at 20°C for another one hr, and then rheological properties were measured with texture analyzer. The hardness of texture modified rice with grains was reduced to 2.3 ~ 4.1 × 104 N/m2 and the hardness of rice with beans was reduced to 3.8 ~ 4.8 × 104 N/m2 depending on mixing ratio. The cohesiveness was reduced by 1/3 ~ 2/3 respectively, while adhesiveness was not changed significantly, compared to those of cooked rice. These results suggest that cooked rice mixed with 30 ~ 40% of grain and 6 ~ 10% of bean would be appropriate for elderly people to consume without chewing difficulty.
In this study, the use of corona discharge plasma jet (CDPJ) for the improvement of hygienic quality of semi-dried mackerel pike (Gwamegi) was investigated. Different microbial contaminants, namely aerobic and marine bacteria, coliform bacteria, Staphylococcus aureus and yeasts and mold, were detected in the range 4.2-6.2 log CFU/g in Gwamegi samples. The CDPJ generated using 20 kV DC and at 58 kHz frequency was used for the treatment of Gwamegi for 0-10 min. The bacterial contaminants were inactivated in the range of 1.9-3.3 log CFU/g on the treatment for 10 min. Additionally, yeasts and mold were inactivated by 3.2 log CFU/g. The inactivation pattern fitted well to the first-order kinetics model. The CDPJ treatment for 10 min did not exert statistically significant changes (P > 0.05) in pH, moisture content, water activity, peroxide value, acid value and volatile basic nitrogen content of Gwamegi in comparison to untreated control samples. On the contrary, significant changes (P < 0.05) were noted in color and thiobarbituric acid reactive substances levels upon the CDPJ treatment. However, the CDPJ-treated Gwamegi samples displayed better sensory properties in terms of appearance, visual color, and flavor as compared to controls.