• Title/Summary/Keyword: A new reagent

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Development of a lateral flow dipstick test for the detection of 4 strains of Salmonella spp. in animal products and animal production environmental samples based on loop-mediated isothermal amplification

  • Wirawan Nuchchanart;Prapasiri Pikoolkhao;Chalermkiat Saengthongpinit
    • Animal Bioscience
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    • v.36 no.4
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    • pp.654-670
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    • 2023
  • Objective: This study aimed to develop loop-mediated isothermal amplification (LAMP) combined with lateral flow dipstick (LFD) and compare it with LAMP-AGE, polymerase chain reaction (PCR), and standard Salmonella culture as reference methods for detecting Salmonella contamination in animal products and animal production environmental samples. Methods: The SalInvA01 primer, derived from the InvA gene and designed as a new probe for LFD detection, was used in developing this study. Adjusting for optimal conditions by temperature, time, and reagent concentration includes evaluating the specificity and limit of detection. The sampling of 120 animal product samples and 350 animal production environmental samples was determined by LAMP-LFD, comparing LAMP-AGE, PCR, and the culture method. Results: Salmonella was amplified using optimal conditions for the LAMP reaction and a DNA probe for LFD at 63℃ for 60 minutes. The specificity test revealed no cross-reactivity with other microorganisms. The limit of detection of LAMP-LFD in pure culture was 3×102 CFU/mL (6 CFU/reaction) and 9.01 pg/μL in genomic DNA. The limit of detection of the LAMP-LFD using artificially inoculated in minced chicken samples with 5 hours of pre-enrichment was 3.4×104 CFU/mL (680 CFU/reaction). For 120 animal product samples, Salmonella was detected by the culture method, LAMP-LFD, LAMP-AGE, and PCR in 10/120 (8.3%). In three hundred fifty animal production environmental samples, Salmonella was detected in 91/350 (26%) by the culture method, equivalent to the detection rates of LAMP-LFD and LAMP-AGE, while PCR achieved 86/350 (24.6%). When comparing sensitivity, specificity, positive predictive value, and accuracy, LAMP-LFD showed the best results at 100%, 95.7%, 86.3%, and 96.6%, respectively. For Kappa index of LAMP-LFD, indicated nearly perfect agreement with culture method. Conclusion: The LAMP-LFD Salmonella detection, which used InvA gene, was highly specific, sensitive, and convenient for identifying Salmonella. Furthermore, this method could be used for Salmonella monitoring and primary screening in animal products and animal production environmental samples.

Preparation and Characterization of Hydrophilic Aminated poly(styrene-ethylene-butylene-styrene) Polymer Membrane (친수성 아민화된 poly(styrene-ethylene-butylene-styrene) 고분자 분리막 제조 및 투습도 특성평가)

  • Son, Tae Yang;Kim, Ji Hyun;Park, Chi Hoon;Nam, Sang Yong
    • Membrane Journal
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    • v.27 no.4
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    • pp.336-343
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    • 2017
  • These days, the quality of indoor air is a very important concept for modern people who have lived in building and is a matter of new thinking. The quality is determined by the temperature and humidity of indoor air. In addition, there is a disadvantage in that energy consumption is severe for indoor air improvement. Therefore, researches on methods to solve such problems using total heat exchange have been actively conducted. So, in this study, aminated poly(styrene-ethylene-butylene-styrene) polymers were synthesized by introducing a hydrophilic substituent, ammonium, into main chain and the properties of synthesized polymers were evaluated. The synthesis was carried out through chloromethylation and amination reactions to introduce ammonium into main chain. As a result, the water uptake and the ion exchange capacity of the synthesized polymers increased as the content of the reaction reagent solution increased. It was confirmed that the important data at the total heat exchange membrane, water vapor transmission rate also increased according to temperature, equivalent.

Spectroscopic Comparison of Photo-oxidation of Outside and Inside of Hair by UVB Irradiation (자외선B 조사에 의한 모발 외부와 내부의 광산화에 관한 분광학적 비교)

  • Ha, Byung-Jo
    • Applied Chemistry for Engineering
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    • v.31 no.2
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    • pp.220-225
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    • 2020
  • Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

The Anti-Sticking Effect of Mixture of Trisodium Phosphate and Citric Acid on Oral Streptococcus species (구강 내 사슬알균 종들에 대한 제3인산나트륨과 구연산의 탈부착 효과)

  • Jung, Choong-Hyun;Cho, Hyung-Hun;Choi, Gwang-Ju;Kang, Seung-Yong;Yang, Nam-Woong
    • Korean Journal of Microbiology
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    • v.44 no.4
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    • pp.289-292
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    • 2008
  • Trisodium phosphate 12 hydrate and citric acid monohydrate mixture showed the strong anti-sticking effect on Streptococcus mutans, Streptococcus mitis, and Streptococcus salivarius, which are adhered to glass beads. Each Streptococcus species was shaking-cultured in brain heart infusion broth containing three glass beads. After 18 hr, glass beads were slightly washed into normal saline by three-pin-pointed pincette. Each three glass-beads set was put into reagent -containing tubes, which have 40 mg of bits of weighing paper for gaining brushing effect as similar as brushing one's teeth. The tubes were shaken by vortex mixer for 10 min except non-oral microbe, Streptococcus agalactiae (5 min). The samples were colony-counted by serial agar dilution method. Experiment was repeated three times for each Streptococcus species. The relative ratios of bacterial de-adherence by reagents were calculated in comparison with normal saline control. The de-adherence degree of citric acid-trisodium phosphate-saline mixture (CTS, pH 6.0) against Streptococcus mutans came to an average of 12.5 times compared with normal saline control. Trisodium-saline (TS, pH 8.4) showed the average of 7.5 times, and citric acid-saline (CS, pH 4.6) showed 6.0 times compared to the control group. The bacterial de-adherence degree against Streptococcus salivarius was each 7.2,2.6 and 2.8 times in above reagent sequence in comparison with saline control. CTS and TS showed 2.4 and 3.4 times of anti-sticking effect on Streptococcus mitis respectively, but CS had no anti-sticking effect on this bacterium. CTS, TS and CS showed 0.7, 0.6, and 0.6 times on non-oral microbe, Streptococcus agalactiae, separately compared with saline control. These results show that oral Streptococcus mutans, Streptococcus salivarius, and Streptococcus mitis, which are causative of dental caries or subacute endocarditis, may be easily removed from oral cavity by CTS mixture. It is conceivable that our experimental results will enable the development of a new conceptive toothpaste to prevent dental caries or subacute endocarditis after drawing teeth.

Lodging Related Traits of Rice Plants as Affected by ′KIM -112′ Application (KIM-112 처리가 벼 도복관련형질에 미치는 영향)

  • Choi, Chung-Don;Kim, Soon-Chul;Lee, Soo-Kwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.3
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    • pp.218-223
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    • 1990
  • This experiment was carried out to obtain basic information on the lodging characteristics and yield components of rice plants by new anti-lodging reagent 'KIM-112' (3%, Wp) application at 30 days before heading (DBH) to 5 DBH under two dosage levels (lg 2g, a. i. /10a) at the Yeongnam Crop Experiment Station in 1989. Culm length was shortened by 10-17% at 1g, a. i. /10a and by 16-23% at 2g of KIM -112 applications. The shortening effect of internode was different by dosages and application times: 2g treatment was greater effect than 19 and early application resulted in shortening of lower internode while this was upper internode at the late application. There were positive correlation between culm length and lodging index, the 1st and the 4th internode lengths had on important effect to lodging index. Thickness of culm wall, culm diameter and weight of basal part of culm were not affected by KIM-112 application. However anti-lodging characters improved by increasing the breaking weight and by decreasing the moment. Lodging index was related to breaking weight, moment and weight of panicle. Heading date by KIM-112 application was delayed one to four days and number of grains per panicle was decreased by shortened panicle length as compared with untreated control, but yield capacity was high a little because of improvement ripening ratio by no lodging.

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Performance Evaluation of In Vitro Diagnostic Reagents for Mycobacterium tuberculosis and Non-tuberculous Mycobacteria by FDA Approval (미국 FDA 허가사례를 통해 본 결핵균 및 비결핵 항산균 체외진단용 시약의 성능평가)

  • Kim, Yeun;Park, Sunyoung;Kim, Jungho;Chang, Yunhee;Ha, Sunmok;Choi, Yeonim;Lee, Hyeyoung
    • Korean Journal of Clinical Laboratory Science
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    • v.50 no.1
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    • pp.20-28
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    • 2018
  • Tuberculosis (TB) is a bacterial infection disease caused by members of the species Mycobacterium tuberculosis (MTB) complex. Approximately one third of the world's population is infected with TB. In Korea, approximately 40,000 new patients are identified each year. Moreover, infections from non-tuberculous mycobacteria (NTM) have also increased. In the diagnosis of TB and NTM, traditional bacterial cultures are required for 3 to 4 weeks. Therefore, rapid and accurate diagnostic tests for TB and NTM are needed. To distinguish between TB and NTM, a range of diagnostic methods have been developed worldwide. In vitro diagnostic assays are constantly being developed to meet the increasing need for the rapid and accurate identification for TB and NTM. On the other hand, the performance evaluations of in vitro diagnostic reagents for TB and NTM are lacking. Recently, the Korea Food and Drug Administration (KFDA) issued a guideline for in vitro diagnostic reagents for MTB and NTM. Here, this study analyzed the performance of currently developed in vitro diagnostic reagents for TB and NTM in the US FDA. This analysis of US FDA approved molecular assays could serve as a useful reference for an evaluation of the reagent performance of TB and NTM.

Technology Trends of Metal Recovery from Wastewater (폐수(廢水) 중(中) 유가금속(有價金屬) 회수기술(回收技術) 동향(動向))

  • Hwang, Young-Gil;Kil, Sang-Cheol;Kim, Jong-Heon
    • Resources Recycling
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    • v.22 no.3
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    • pp.91-99
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    • 2013
  • Steel industry which has been accomplishes the base of our country economy, automobile and electronic industry are taking charge of the role, whose electroplating is important. Large amount of wastewater and various metal salts, including hazardous materials was generated from the electroplating pre-treatment, plating, washing and post-plating. Currently, the general wastewater follows in the environmental law and neutralization after controlling, sludge where the various metal is mixed reclaims below multiple regulative and trust it is controlling. The sludge which includes the gas price metal reclaims in the field and trust it controls. a reclamation price of land it is insufficient but and the control expense holds plentifully and it loses the gas price metal which is valuable. Consequently, The research regarding to recover a gas price metal actively from this waste water, it is advanced. A new method to recover valuable metals from electroplating wastewater synthesis of metal sulfides using topical methods utilizing iron oxidizing bacteria, reagent of sulfides and solvent extraction using an organic solvent, such as the development of the law to recover these metals and metal sulfides of wastewater using selective recovery have been studied. By using these wastewater treatment method under frequency above 95%, it has been obtained the valuable metal from the wastewater, where the metal ion of Fe, Cu, Zn and Ni complexes was mixed. As we discuss the wastewater, which has been discharged from electroplating process, it is important and will be applied to the resources of metal in the urban mine.

Synthesis and Characterization of Polyethylenimine-conjugated Polydiacetylene Liposome as a Gene Delivery Carrier (폴리디아세틸렌 리포좀 표면에 저분자량의 폴리에틸렌이민을 연결한 새로운 유전자 전달체 합성 및 특징 연구)

  • Lee, Young Hwa;Yim, Kang Hyuck;Heo, Jungseok;Choi, Joon Sig
    • Polymer(Korea)
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    • v.38 no.1
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    • pp.43-48
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    • 2014
  • In this paper, we made a new polycationic polymeric liposome composed of low molecular weight polyethylenimine (PEI) and 10,12-pentacosadiynoic acid (PCDA). PCDA liposome was prepared by ultraviolet irradiation. PEI was further conjugated on the surface of the polymerized PCDA liposome using coupling reagents to make PCDA-PEI. The blue-to-red transition of PCDA liposome was observed during the coupling reaction. The size distribution of liposome and complexes with plasmid DNA was measured by dynamic light scattering (DLS). The complex formation was also identified by agarose gel electrophoresis and PicoGreen reagent assay. We confirmed the complex formation of the polymeric liposome with DNA and then performed transfection and cytotoxicity assay in HEK 293 and HeLa cells. As a result, PCDA-PEI showed significant gene transfection efficiency and low cytotoxicity. This study shows that PEI-conjugated PCDA liposome could be an efficient gene or drug delivery carrier.

Simultaneous GC/MS Analyses of Organic acids and Amino acids in Urine using TMS-TFA derivative (TMS-TFA 유도체화를 이용한 소변여지 중 유기산과 아미노산의 GC/MS 동시분석)

  • Yoon, Hye-Ran
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.107-114
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    • 2006
  • Early diagnosis and medical intervention are critical for the treatment of patients with metabolic disorders. A rapid analytical method was developed for simultaneous quantification of organic acids and amino acids in urine without labor-intensive pre-extraction procedure showing high sensitivity and specificity. A new method consisted of simple two-step trimethylsilyl (TMS)-trifluoroacetyl (TFA) derivatization using GC/MS-selective ion monitoring (SIM). Filter paper urine specimens were dried under nitrogen after being fortified with internal standard (tropate) in a mixture of distilled water and methanol. Methyl orange was added to the residue as indicator reagent. Silyl derivative of carboxylic functional group was followed by trifluoroacetyl derivative for amino functional group. N-methyl-N-(trimethylsilyl-trifluoroacetamide) and N-methyl-bistrifluoroacetamide were consecutively added and heated for 15-20 min at $65^{\circ}C-70^{\circ}C$, for TMS-TFA derivative, respectively. This reactant was analyzed by GC/MS-SIM. Linear dynamic range showed 0.001-50 mg with the detection limit of (S/N=3) 10-200 ng, and the quantification limit of 80-900 ng in urine. Correlation coefficient of regression line was 0.994-0.998. When the method was applied to the patients 'urine, it clearly differentiated the normal from the patient with metabolic disorder. The study showed that the developed method could be the method of choices in rapid and sensitive screening for organic aciduria and amino acidopathy.

Evaluation of the Effects of Interfering Factors on the Bacterial Endotoxin Testing of Radiopharmaceuticals (방사성의약품의 박테리아 엔도톡신 시험에서 반응간섭인자들의 영향에 대한 평가)

  • Jun Young PARK
    • Korean Journal of Clinical Laboratory Science
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    • v.56 no.2
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    • pp.171-180
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    • 2024
  • The endotoxin test is based on the reaction between Limulus Amebocyte Lysate (LAL) and the lipopolysaccharides of Gram-negative bacteria. In this study, we sought to identify factors that interfere with the LAL testing of radiopharmaceuticals and evaluated acceptable ranges. A gel-clot LAL test and a chromogenic LAL test were used as endotoxin tests. We compared the performances of the Endosafe LAL and recombinant Endosafe Recombinant Cascade Reagent (rCR) cartridges for the chromogenic test. The factors that interfered with 68Ga-DOTATOC injection were pH, 4-(2-hydroxyethyl) piperazine-1-ethanesulfonic acid (HEPES) buffer, and organic solvents, especially ethanol. However, interference by these factors was overcome by diluting the 68Ga-DOTATOC injection tenfold. In addition, no interference was observed at pH values between 4 and 8, at a HEPES concentration of 2,000 ㎍/mL, or an ethanol concentration of <1%. Furthermore, results showed that interfering factors had similar effects on the performances of the Endosafe LAL and Endosafe rCR cartridges. The results of this study are expected to be useful for evaluating factors that interfere with the endotoxin testing of new radiopharmaceuticals.