• Korean Journal of Materials Research
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• v.33 no.7
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• pp.285-294
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• 2023

Porous ceramics are used in various industrial applications based on their physical properties, including isolation, storage, and thermal barrier properties. However, traditional manufacturing environments require additional steps to control artificial pores and limit deformities, because they rely on limited molding methods. To overcome this drawback, many studies have recently focused on fabricating porous structures using additive manufacturing techniques. In particular, the binder jet technology enables high porosity and various types of designs, and avoids the limitations of existing manufacturing processes. In this study, we investigated process optimization for manufacturing porous ceramic filters using the binder jet technology. In binder jet technology, the flowability of the powder used as the base material is an important factor, as well as compatibility with the binder in the process and for the final print. Flow agents and secondary binders were used to optimize the flowability and compatibility of the powders. In addition, the effects of the amount of added glass frit, and changes in sintering temperature on the microstructure, porosity and mechanical properties of the final printed product were investigated.

• IMMUNE NETWORK
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• v.21 no.6
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• pp.39.1-39.18
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• 2021

The high virulent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that emerged in China at the end of 2019 has generated novel coronavirus disease, coronavirus disease 2019 (COVID-19), causing a pandemic worldwide. Every country has made great efforts to struggle against SARS-CoV-2 infection, including massive vaccination, immunological patients' surveillance, and the utilization of convalescence plasma for COVID-19 therapy. These efforts are associated with the attempts to increase the titers of SARS-CoV-2 neutralizing Abs (nAbs) generated either after infection or vaccination that represent the body's immune status. As there is no standard therapy for COVID-19 yet, virus eradication will mainly depend on these nAbs contents in the body. Therefore, serological nAbs neutralization assays become a requirement for researchers and clinicians to measure nAbs titers. Different platforms have been developed to evaluate nAbs titers utilizing various epitopes sources, including neutralization assays based on the live virus, pseudovirus, and neutralization assays utilizing recombinant SARS-CoV-2 S glycoprotein receptor binding site, receptor-binding domain. As a standard neutralization assay, the plaque reduction neutralization test (PRNT) requires isolation and propagation of live pathogenic SARS-CoV-2 virus conducted in a BSL-3 containment. Hence, other surrogate neutralization assays relevant to the PRNT play important alternatives that offer better safety besides facilitating high throughput analyses. This review discusses the current neutralization assay platforms used to evaluate nAbs, their techniques, advantages, and limitations.

• Journal of Veterinary Science
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• v.25 no.4
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• pp.55.1-55.12
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• 2024

Importance: Neonatal calf diarrhea is a major cause of mortality in newborn calves worldwide, posing a significant challenge in bovine herds. Group A Bovine Rotaviruses (BRVA) are the primary contributors to severe gastroenteritis in calves under two months old. Objectives: This study examined the prevalence and molecular characterization of BRVA in neonatal calves in Gujarat, India. Methods: Sixty-nine diarrheic fecal samples were collected and subjected to various molecular methods of BRVA detection, isolation, and characterization. Results: The latex agglutination test (LAT), electropherotyping (RNA-PAGE), and reverse transcription polymerase chain reaction revealed positivity rates of 39.13%, 20.30%, and 37.70%, respectively. RNA-PAGE identified 11 bands with a 4:2:3:2 migration pattern, indicative of the segmented genome of BRVA. BRVA was successfully isolated from LATpositive samples, with 26 samples exhibiting clear cytopathic effects upon passage in MA-104 cell lines. Genotyping identified G10 as the predominant G genotype, with P[11] genotypes comprising 76.92% of the isolates. The most common G/P combination was G10P[11], highlighting its zoonotic potential. Conclusions and Relevance: These findings underscore the importance of molecular detection and genotyping for effective vaccine development. This study provides crucial insights into the prevalent G and P genotypes of BRVA in Gujarat, India, aiding in the development of targeted control measures.

• Journal of Animal Reproduction and Biotechnology
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• v.39 no.3
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• pp.212-219
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• 2024

Background: This study explores the potential of discarded male layer embryos as a sustainable and non-GMO cell source for cultivated chicken meat production. The research aims to identify efficient methods for isolating muscle progenitor cells (MPCs) with high proliferative potential by conducting transcriptome analysis on thigh muscle tissues from both male and female chick embryos. Methods: Transcriptome analysis was performed on the thigh muscle tissues of male and female chick embryos, aged 12-13 days, (n = 4 each), to investigate the gene expression profiles and identify strategies for efficiently isolating MPCs. This approach aims to pinpoint techniques that would allow for the selection of MPCs with optimal growth and proliferation capabilities. Results: Using heatmap, hierarchical clustering, and multidimensional scaling (MDS), we found no significant sex-based differences in gene expression, except for the overexpression of the female-specific gene LIPBLL. The expression of muscle stem cell factors, including PAX3, PAX7, and other myogenic regulatory genes, showed no significant variation. However, to recover MPC-rich cells isolated from male thigh muscle, we found that by the pre-plating 7 stage, myogenesis-related genes, MYHs and MUSTN1 were minimally expressed, while the cell cycle arrest gene CDKN1A sharply increased. Conclusions: Our findings suggest that simple cell isolation directly from tissue is a more scalable and efficient approach for cultivated meat production, compared to labor-intensive pre-plating methods, making it a viable solution for sustainable research and resource recycling.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.763-771
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• 2012

In this study, total antioxidant properties of extracts from different parts of Lespedeza bicolor were determined using techniques of measuring 1,1-diphenyl-2-picryl hydrazyl/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)-radical scavenging activity and total phenolic contents. The total antioxidant activities of leaf, stem and root extracts from various solvents (water, 50, 70, 100% ethanol, and hot-water) indicated that 50 and 70% ethanol extracts have high radical scavenging activities and phenolic contents. A systematic approach was used to determine the total antioxidant activity of different solvent fractions of the Lespedeza bicolor extracts, partitioning with chloroform, ethyl acetate, n-butanol, and water, and the ethyl acetate fraction was found to have the strongest antioxidant activity. Antioxidant assay-guided isolation was carried out to isolate potential antioxidant compounds. The ethyl acetate fraction of the leaf extract was subjected to silica gel, LH-20 and RP-18 column chromatography successively, and afforded compound 1, which was identified as eriodictyol by NMR and MS analysis, after which its antioxidant activity was determined.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.1-17
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• 2000

Carcinogen-DNA adduct analysis has potential for biomonitoring the earliest effects of exposure to many chemical carcinogens. They are the covalent reaction products of electrophiles and nucleophilic sites on DNA and the initial damage to DNA induced by many carcinogens. So many researchers begin to use them as biomarker for monitoring the earliest exposure of carcinogens and develop the effective analytical techniques about them. Randerath, Gupta and coworkers(1981, 1982) has also developed a $^{32}P$-postlabelling method as one among them. A major project for biomonitoring workers with carcinogen-DNA adducts is to develop non-invasive samples instead of tissues of target organs such as baldder and lung. This study use the exfoliated urothelial cells in urine for examine benzidine-DNA adducts. The content of exfoliated urothelial cells is not enough to significantly measure DNA content with spectrophotometer, and require the another way. So firstly washing the collected cells with PBS and 70% ethanol and centrifuge them for removing the crystals in urine, which block the isolation of DNA adducts. And then, measure the total nucleotide after $^{32}P$-postlabelling for calculating RAL. $[{\gamma}-^{32}P]ATP$ using for $^{32}P$-postlabelling, can synthesize with $[^{32}P]H_3PO_4$, and reagent and enzyme mixture (RM, EM), which is very economic in case of requiring a lot of them. Chromatography was composed of two steps. First step was to separate adduct ones from unadducted nucleotide, and secondary step was separate each adduct, which were performed with 4 kinds of solvents and different directions on TLC. With this procedure, we measure the DNA adducts in exfoliated urothelial cells of workers who were employed in benzidine and benzidine-dye company. RAL of adducts were $89.0{\times}10^7$ and $57.0{\times}10^7$ in them. In conclusion, we can significantly measure the DNA adduct in exfoliated urothelial cells by using the above $^{32}P$-postlabelling procedures, and use them to be biomonitoring workers who exposed carcinogens.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.137-144
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• 2007

Koji is steamed rice that has had koji-kin, or koji mold spores, cultivated onto it. The isolation, culture, and microscopic examination of molds in the koji require the use of the selective media and special microscopic slide techniques. If simple wet mount slides of molds were attempted, it became apparent that wet mount slides made from mold colonies usually don't reveal the arrangement of spores that is so necessary in identification. The process of merely transferring hyphae to a slide breaks up the hyphae and sporangiophores in such a way that identification becomes very difficult. The slide culture method is superior to wet mounts in that the hyphae, sporangiophores, and spores remain more or less intact when transferred. The procedure that will be used to produce a mold culture on a slide that can be observed directly on the slide. We investigated the contamination rate of penicillium spp. on the 21 kinds of koji distributed at Korea. The contamination rate of Penicillium spp. were not detected at 21 products by slide culture method. These results will be used to reestablish a mold determination of koji and food in Food Additives Code.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.89-94
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• 1996

Three sesquiterpene ortho-naphthoquinones were isolated from the methanolic extract of root bark of Ulmus davidiana Planch whose stem and root bark have been used as an oriental medicine for the treatment of edema, mastitis, gastric cancer and inflammation. The structures of these compounds were established on the basis of spectral data obtained from UV-vis, IR, HR-EIMS and NMR spectrometry, including the pulse field gradient (PFG)-HMQC and HMBC techniques. Their structures were determined as 2,3-dihydro-3,6,9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione, 3,6,9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione and 2,3-dihydro-4-hedroxy-3,6, 9-trimethylnaphtho(1,8-b,c)pyran-7,8-dione, which were identified as mansonones E. F and H, respectively. These compounds have originally been isolated from Mansonia altissima Chev, but have never been isolated from Ulmus davidiana Planch. Especially, mansonone H was isolated for the first time from Ulmaceae. The mismatched carbon chemical shifts of mansonones E and F in the reported literature were corrected by the aid of the PFG-HMBC spectral data.

• Clinical and Experimental Reproductive Medicine
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• v.20 no.2
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• pp.107-115
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• 1993

Procedures to separate motile. normal & motile and acrosome-reacted sperm with high efficiency have clinical application in Assisted Reproductive Technology in terms of increasing the probability of fertilization by a normal sperm and subsequent normal embryonic development. This study evaluated the effects of 10 sperm preparation techniques [Swim-up from a washed pellet (SU). Swim-up from semen (SO). Continuous Percoll Gradients I (PIC). Discontinuous Percoll Gradients I (PID). Continuous Percoll Gradients II(P II C). Discontinuous Percoll Gradients II(P II D), SpermPrep (SFC). Wang's tube (WT). Albumin Gradients (AG), Low temperature capacitation (LTC)] on motility (%), normal morphology (%), motile sperm recovery rate(%). morphologically normal & motile sperm recovery rate (%), true acrosome reaction (%) and fertilizing ability. A P II D proved to be an effective means of separating morphologically normal & motile sperm. Our results indicated the P II D has advantages as compared with other methods in terms of recovery rate. enhancement of motility and normal morphology. And a LTC seems to be an effective means of enhancing the true acrosome reaction and fertilizing ability. These results suggest that the combined method of LTC and P II D for separation of morphologically normal & motile sperm and acrosome reacted sperm may be a useful procedure for intrauterine insemination and in vitro fertilization in the management of male factor infertility as well as for isolation of subpopulation of sperm for basic research.

• Journal of Environmental Health Sciences
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• v.11 no.2
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• pp.41-54
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• 1985

This study was conducted for the improvement of milk quality and milk hygiene in public health point of view. Investigation of mastiris infection rate, isolation and identification of causative microorganisms in CMT positive milk, investigation of milk contamination level by measuring the bacteria and soma tic cell counts and investigation of dairy management in farms were performed on 1.605 quarters milk of 434 cows of 20 dairy farms in Gyunggi-area from September 1983 to March 1984. The results were summarized as follows 1. Sixteen (3.7%) of 434 cows were found to be infected with clinical mastiris. 234 (53.9%) of 434 cows and 608(37.9%) of 1, 605 quarters were found to be infected with subclinical mastiris. 2. The causative microorganisms isolated were Staphylococcus aureus (38.3%), Staphylococcus epidermidis(21.0%), Micrococci(13.6%), Streptococcus spp. (12.3%), E. coli (7.4%), Fungus & Yeast (1.6%) and others (5.8%). 3. Total numbers of bacteria were $9.2{\times}10^6$ to $1.21{\times}10^7/ml$(av. $1.805{\times} 10^7/ml$), numbers of coliform bacteria were $4.1{\times} 10^5$ to $9.4{\times} 10^5$/ml(av. $7.05{\times} 10^5$/ml) and somatic cell counts were $4.8{\times} 10^5$ to $1.52{\times} 10^6$ cells/ml (av. $9.5{\times} 10^5$cells/ml) in bulk milk. 4. As comparing with CMT score of +, ++ and +++, somatic cell counts were $3.4{\times} 10^5$ to $1.64{\times} 10^6$ cells/ml (av. $6.41{\times} 10^5$cells/ml), $5.4{\times} 10^5$ to $2.75{\times} 10^6$ cells/ml(av. $1.762{\times} 10^6$cells/ml) and $1.97{\times} 10^6$ to $9.75{\times} 10^6$ cells/ml(av. $7.781{\times} 10^6$cells/ml), respectively. 5. In investigation on dairy management, performance of dry cow therapy, teat dipping after milking, disinfection of milking machine at every milking, replacement of milk liner within 6months and opportunity of acquirement for the mastiris control techniques by dairy education were 65%, 40%, 45%, 55% and 50% in 20 dairy farms, respectively.