• Title/Summary/Keyword: oral challenge model

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Effect of frozen storage and various concentrations of sucrose media on survivability of enterotoxigenic Escherichia coli (ETEC) for oral challenge of weaner pigs

  • Cho, Hyun Min;Kang, Joo Won;Kim, Yeong Kuk;Lee, Joo Bin;Oh, Chan Yi;Heo, Jung Min;Yi, Young-Joo
    • Korean Journal of Agricultural Science
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    • v.43 no.5
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    • pp.788-793
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    • 2016
  • Post-weaning diarrhea (PWD), mostly caused by enterotoxigenic Escherichia coli (ETEC), remains to be a major source of economic loss in swine industry. The use of the ETEC-oral challenge model is often applied to mimic unsanitary commercial swine farm conditions where pathogens and unknown complex microbes exist and can cause severe infections in pigs. The purpose of this study was (1) to estimate ETEC density using spectrophotometric computation, (2) to determine survivability of ETEC after storing at $-20^{\circ}C$ for 7 days, and (3) to evaluate survivability of ETEC after blending with diluted sweeteners (0, 5, 10, 20, and 40% sucrose in phosphate buffered saline [PBS]). Cell density was quantified using UV-VIS spectrophotometer and counting ETEC colony forming units (cfu) at 0, 30, 60, 90, 120, 150, 180, 210, and 240 min. The established linear equation ($y=0.0031x^2-0.0079x+0.0043$ and $y=0.0046x^2-0.0151x+0.0113$) was used for robust quantification of each ETEC cell density. ETEC stored at $-20^{\circ}C$ showed 108 cfu/mL after thawing and incubation. When ETEC was blended with sweeteners (20 and 40%), survival of ETEC was decreased by 58 and 54% in 5 min post blending. However, addition of 20% of sweetener resulted in a higher survivability than those with other media concentrations. Therefore, the use of ETEC-oral challenge model would be possible as a stable method if we could confirm the appropriate medium that increases survivability of ETEC in weaner pigs.

Gut Health of Pigs: Challenge Models and Response Criteria with a Critical Analysis of the Effectiveness of Selected Feed Additives - A Review

  • Adewole, D.I.;Kim, I.H.;Nyachoti, C.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.7
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    • pp.909-924
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    • 2016
  • The gut is the largest organ that helps with the immune function. Gut health, especially in young pigs has a significant benefit to health and performance. In an attempt to maintain and enhance intestinal health in pigs and improve productivity in the absence of in-feed antibiotics, researchers have evaluated a wide range of feed additives. Some of these additives such as zinc oxide, copper sulphate, egg yolk antibodies, mannan-oligosaccharides and spray dried porcine plasma and their effectiveness are discussed in this review. One approach to evaluate the effectiveness of these additives in vivo is to use an appropriate disease challenge model. Over the years, researchers have used a number of challenge models which include the use of specific strains of enterotoxigenic Escherichia coli, bacteria lipopolysaccharide challenge, oral challenge with Salmonella enteric serotype Typhimurium, sanitation challenge, and Lawsonia intercellularis challenge. These challenge models together with the criteria used to evaluate the responses of the animals to them are also discussed in this review.

Effect of Picrorrhiza Rhizoma on Dinitrofluorobenzene-induced Contact Dermatitis (Type I allergy)

  • Park, Ji-Ha;Lee, Sang-Nam;Ku, Sae-Kwang
    • Biomolecules & Therapeutics
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    • v.16 no.3
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    • pp.237-242
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    • 2008
  • The effect of Picrorrhiza Rhizoma (PR) aqueous extracts were evaluated on 2,4-dinitrofluorobenzene (DNFB)-induced contact dermatitis, type I allergic model. Contact dermatitis was induced by sensitization with dinitrophenyl-derivatized ovalbumin (DNP-OVA) and DNFB challenge as antigen. Three different concentrations of PR extracts (300,150 and 75mg/kg) were orally administered to DNP-OVA sensitization mice once a day for 7 days with reference materials; dexamethasone (15mg/kg, intraperitoneal treatment). End of 7 days oral administration of PR extracts or intraperitoneal treatment of dexamethasone, the changes on the edematous changes and scratching behavior were measured. Immediate after DNFB challenge on ear or paw of DNP-OVA sensitized mice, increases of ear and paw thicknesses and weights were detected with anterior ear skin (dermis to epidermis) thickness and paw scratching behavior increases. However, these DNFB-induced increases on ear and paw thicknesses, weights and scratching behaviors were decreased by treatment of all three different dosages of PR extracts and dexamethasone, respectively. In addition, the increases of anterior skin thicknesses were also dramatically inhibited by treatment of all three different dosages of PR extracts and dexamethasone at histopathological observations. The results obtained in this study suggest that oral treatment of PR extracts also has relatively favorable effects on allergic dermatitis.

Effect of DHU001, a Polyherbal Formula, on Dinitrofluorobenzene-induced Contact Dermatitis (Type I allergy)

  • Lee, Hyeung-Sik;Lee, Byung-Chang;Ku, Sae-Kwang
    • Toxicological Research
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    • v.26 no.2
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    • pp.123-130
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    • 2010
  • The effect of DHU001, a mixed herbal formula consisted of 7 types aqueous extracts for various respiratory disorders were evaluated on 2,4-dinitrofluorobenzene (DNFB)-induced contact dermatitis, type I allergic model. Contact dermatitis was induced by sensitization with dinitrophenyl-derivatized ovalbumin (DNP-OVA) and DNFB challenge as antigen. Two different dosages of DHU001 (300 and 150 mg/kg) were orally administered to DNP-OVA sensitization mice once a day for 7 days with reference material, dexamethasone (15 mg/kg, intraperitoneal treatment). End of 7 days oral administration of DHU001 extracts or intraperitoneal treatment of dexamethasone, the changes on the edematous changes and scratching behavior were measured. Immediate after DNFB challenge on ear or paw of DNP-OVA sensitized mice, increases of ear and paw thicknesses and weights were detected with anterior ear skin (dermis to epidermis) thickness and paw scratching behavior increases. However, these contact dermatitis signs induced by DNFB treatment were reduced by treatment of the both different dosages of DHU001 and dexamethasone, respectively. The results obtained in this study suggest that oral treatment of DHU001 extracts also has relatively favorable effects on contact dermatitis.

Development of the efficient insulin secretion model for the oral glucose tolerance test

  • Lee, Jae-Cheol;Lee, Sun-Hyeok;Im, Chae-Heon
    • Proceeding of EDISON Challenge
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    • 2017.03a
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    • pp.635-642
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    • 2017
  • Cobelli와 그의 동료들이 제안한 포도당 농도에 따른 췌장의 인슐린 분비 모델(Cobelli model)은 비교적 단순한 모델이지만 Grodsky의 실험 뿐만 아니라 일련의 관련 실험을 재현하였다. 하지만 이 모델은 췌장 베타세포 내 인슐린 분포를 미분형식으로 표현하였고, 적분을 통해 인슐린 양을 계산하였다. 그로 인해 각 시간 스텝에서 포도당의 양에 따라 적분 구간만큼 반복적인 계산을 수행해야만 했다. 이에 본 연구에서는 Cobelli model을 재현하면서 좀 더 효과적으로 결과를 얻을 수 있는 새로운 Multi-RRP model을 제시하였다. Multi-RRP model은 RRP를 과립의 자극 여부에 따라 RRPhigh와 RRPlow로 나누어 각각의 인슐린 분비를 계산하는 방법으로, 포도당의 변화에 따라 RRP의 수를 증가시켜 인슐린의 분비량을 산출한다. 이 Multi-RRP model의 시뮬레이션 결과는 Cobelli model과 동일한 경향을 보이며, Grodsky의 계단 실험과의 비교에서는 Cobelli model보다 실험 결과에 더 접근한다. 또한, 시뮬레이션 시간 비교를 통해 효율성을 확인하였고, Multi-RRP model이 Cobelli model보다 16배 이상 효율이 더 높은 것으로 확인되었다.

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Establishment of a linear regression equation for quantification of beta-hemolytic Escherichia coli in different media and survival of hemolytic Escherichia coli after blending with three different media

  • Kim, Jae Cheol;Pluske, John R.;Yoo, Jaehong;Heo, Jung Min
    • Korean Journal of Agricultural Science
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    • v.41 no.2
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    • pp.135-139
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    • 2014
  • Pathogenic E. coli associated post-weaning diarrhea (PWD) and edema disease are common diseases in commercially-housed weanling pigs. An enterotoxigenic E. coli (ETEC) oral challenge model has been used to mimic the physiological responses observed in commercial conditions. However, an oral challenge procedure has two major limitations: (1) the ETEC cell density is unknown at the point of oral inoculation, and (2) blending ETEC with traditional TSB (trypticase soy broth) is not palatable and hence decreases acceptability by piglets. Therefore, the purposes of this study were to (1) establish a regression equation that can be used for estimation of ETEC concentration in dilution media using the spectrophotometric measurement of cell density; and (2) examine survival of ETEC after blending either with TSB, sweetener or dextrose. A strain of ETEC (serogroup beta-hemolytic E. coli O149; K91; F4; toxins LT, STa, STb) was grown in TSB for 3.5 hours, centrifuged, the supernatant was discarded, and the ETEC pellet was then blended either with TSB (100 mL), sweetener (60 mL TSB + 40 mL fruit flavored concentrate), or dextrose (50 mL TSB + 50 mL dextrose; 0.5g/mL dextrose). Cell density was measured using the colorimetric method and also plated on a 5% sheep blood agar for counting of ETEC colony forming units at 0, 5, 35, 65 and 125 min after blending. The optical density at 600 nm explained 83% of ETEC colony forming units, indicating that the established linear equation (y= 6E+08x - 4E+07, P<0.004) can be used for robust quantification of ETEC cell density in TSB, sweetener and dextrose media. When ETEC was blended with sweetener and dextrose, survival of ETEC was decreased by 45% and 72% within 5 min post-blending. Therefore, further research is required to find out the suitable medium that has potential to improve palatability without compromising survival of ETEC.

Glycoproteins isolated from Atractylodes macrocephala Koidz improve protective immune response induction in a mouse model

  • Kim, Kyoung-A.;Son, Young-Ok;Kim, So-Soon;Jang, Yong-Suk;Baek, Young-Hyun;Kim, Chun-Chu;Lee, Jeong-Hoon;Lee, Jeong-Chae
    • Food Science and Biotechnology
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    • v.27 no.6
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    • pp.1823-1831
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    • 2018
  • This study examined the efficacy of Atractylodes macrocephala Koidz (AMK) protein and polysaccharide extracts as adjuvant or adjuvant booster when given together with porcine pleuropneumonia vaccine. Experimental mice (n = 5/group) were subcutaneously immunized with $25{\mu}g$ ApxIIA #3 antigen, a target protein against A. pleuropneumoniae, together with alum and/or various concentrations ($0-500{\mu}g$) of the AMK extracts, while the control group received PBS only. Immunization with ApxIIA #3 antigen increased the antigen-specific IgG titer and this increase was enhanced in the immunization together with AMK protein, but not polysaccharide extract. Supplementation of AMK protein extract exhibited dose-dependent increases in the antigen-induced protective immunity against A. pleuropneumoniae challenge and in the lymphocyte proliferation specific to the antigen. Glycoproteins present in the AMK extract were the active components responsible for immune response induction. Collectively, the present findings suggest that AMK glycoproteins are useful as immune stimulating adjuvant or adjuvant booster.

Immuno-Modulatory Effects of Bacteriocin-Producing Pediococcus pentosaceus JWS 939 in Mice

  • Choi, Hyun-Jong;Kim, Ji-Ye;Shin, Myeong-Su;Lee, Sang-Myeong;Lee, Wan-Kyu
    • Food Science of Animal Resources
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    • v.31 no.5
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    • pp.719-726
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    • 2011
  • Pediococcus pentosaceus JWS 939 (JWS 939) is a nonpathogenic bacteriocin-producing probiotic isolated from the duck intestine. This study assessed the immunomodulatory effects of JWS 939 and compared them with those of Lactobacillus rhamnosus GG (LGG), a well-known immune enhancer. The immune-enhancing effects of JWS 939 were measured by measuring the production of nitric oxide (NO) and cytokines in C57BL/6 mouse peritoneal macrophages. In addition, to assess the immune enhancement abilities of JWS 939, in vivo, a Listeria monocytogenes challenge mice model was used. The results showed that heat-killed JWS 939 induced more NO and interleukin (IL)-$1{\beta}$ production in mouse peritoneal macrophages than in LGG, and that oral administration of viable JWS 939 in mice increased more NO, IL-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$ level than in LGG in serum upon L. monocytogenes challenge. In addition, mice fed with JWS 939 had a longer survival time after lethal challenge with L. monocytogenes, and these effects were stronger than those induced by LGG. Collectively, P. pentosaceus JWS 939 is a remarkable strain that, by releasing bacteriocin and enhancing host immune responses, may have potential as a duck feed additive to suppress pathogens.

Evaluation of Factors that Can Affect Protective Immune Responses Following Oral Immunization of Recombinant Helicobacter pylori Urease Apoenzyme

  • Kim, Jang-Seoung;Chang, Ji-Hoon;Park, Eun-Jeong;Chung, Soo-Il;Yum, Jung-Sun
    • Journal of Microbiology and Biotechnology
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    • v.10 no.6
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    • pp.865-872
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    • 2000
  • Helocobacter phylori is the major cause of gastritis, peptic ulcer, and a principal risk factor for gastric cancer. As the firs step towards a vaccine against H. pylori infection, Hy.pylori urease was expressed and purified as a recombinant apoenzyme (rUrease) in E. coli. In order to develop an effective immunization protocol using rUrease, the host immune responses were evaluated after the oral immunization of mice with rUrease preparations plus cholera toxin relative to various conditions, such as the physical nature of the antigen, the frequency of the booster immunization, the dose of the antigen, and the route of administration. The protective efficacy was assessed using a quantitative culture following an H. pylori SS1 challenge. It was demonstrated that rUrease, due to its particulated nature, was more superior than the UreB subunit as a vaccine antigen. The oral immunization of rUrease elicited significant systemic and secretory antibody responses, and activated predominantly Th2-type cellular responses. The bacterial colonization was significantly reduced (~100-fold) in those mice immunized with three or four weekly oran doses of rUrease plus cholera toxin (p<0.05), when compared to the non-immunized/challenged controls. The protection correlated well with the elicited secretory IgA level against rUrease, and these secretory antibody responses were highly dependent on the frequency of the booster immunization, yet unaffected by the dose of the antigen (25-200$\mu\textrm{g}$). These results demonstrate the remarkable potential of rUrease as a vaccine antigen, thereby strengthening the possibility of developing an H. pylori vaccine for humans.

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Real-time Tooth Region Detection in Intraoral Scanner Images with Deep Learning (딥러닝을 이용한 구강 스캐너 이미지 내 치아 영역 실시간 검출)

  • Na-Yun, Park;Ji-Hoon Kim;Tae-Min Kim;Kyeong-Jin Song;Yu-Jin Byun;Min-Ju Kang․;Kyungkoo Jun;Jae-Gon Kim
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.46 no.3
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    • pp.1-6
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    • 2023
  • In the realm of dental prosthesis fabrication, obtaining accurate impressions has historically been a challenging and inefficient process, often hindered by hygiene concerns and patient discomfort. Addressing these limitations, Company D recently introduced a cutting-edge solution by harnessing the potential of intraoral scan images to create 3D dental models. However, the complexity of these scan images, encompassing not only teeth and gums but also the palate, tongue, and other structures, posed a new set of challenges. In response, we propose a sophisticated real-time image segmentation algorithm that selectively extracts pertinent data, specifically focusing on teeth and gums, from oral scan images obtained through Company D's oral scanner for 3D model generation. A key challenge we tackled was the detection of the intricate molar regions, common in dental imaging, which we effectively addressed through intelligent data augmentation for enhanced training. By placing significant emphasis on both accuracy and speed, critical factors for real-time intraoral scanning, our proposed algorithm demonstrated exceptional performance, boasting an impressive accuracy rate of 0.91 and an unrivaled FPS of 92.4. Compared to existing algorithms, our solution exhibited superior outcomes when integrated into Company D's oral scanner. This algorithm is scheduled for deployment and commercialization within Company D's intraoral scanner.