• Title/Summary/Keyword: Laboratory animal

Search Result 2,986, Processing Time 0.029 seconds

Establishment of Test Conditions and Interlaboratory Comparison Study of Neuro-2a Assay for Saxitoxin Detection (Saxitoxin 검출을 위한 Neuro-2a 시험법 조건 확립 및 실험실 간 변동성 비교 연구)

  • Youngjin Kim;Jooree Seo;Jun Kim;Jeong-In Park;Jong Hee Kim;Hyun Park;Young-Seok Han;Youn-Jung Kim
    • Journal of Marine Life Science
    • /
    • v.9 no.1
    • /
    • pp.9-21
    • /
    • 2024
  • Paralytic shellfish poisoning (PSP) including Saxitoxin (STX) is caused by harmful algae, and poisoning occurs when the contaminated seafood is consumed. The mouse bioassay (MBA), a standard test method for detecting PSP, is being sanctioned in many countries due to its low detection limit and the animal concerns. An alternative to the MBA is the Neuro-2a cell-based assay. This study aimed to establish various test conditions for Neuro-2a assay, including cell density, culture conditions, and STX treatment conditions, to suit the domestic laboratory environment. As a result, the initial cell density was set to 40,000 cells/well and the incubation time to 24 hours. Additionally, the concentration of Ouabain and Veratridine (O/V) was set to 500/50 μM, at which most cells died. In this study, we identified eight concentrations of STX, ranging from 368 to 47,056 fg/μl, which produced an S-shaped dose-response curve when treated with O/V. Through inter-laboratory variability comparison of the Neuro-2a assay, we established five Quality Control Criteria to verify the appropriateness of the experiments and six Data Criteria (Top and Bottom OD, EC50, EC20, Hill slop, and R2 of graph) to determine the reliability of the experimental data. The Neuro-2a assay conducted under the established conditions showed an EC50 value of approximately 1,800~3,500 fg/μl. The intra- & inter-lab variability comparison results showed that the coefficients of variation (CVs) for the Quality Control and Data values ranged from 1.98% to 29.15%, confirming the reproducibility of the experiments. This study presented Quality Control Criteria and Data Criteria to assess the appropriateness of the experiments and confirmed the excellent repeatability and reproducibility of the Neuro-2a assay. To apply the Neuro-2a assay as an alternative method for detecting PSP in domestic seafood, it is essential to establish a toxin extraction method from seafood and toxin quantification methods, and perform correlation analysis with MBA and instrumental analysis methods.

Effects of Total Mixed Fermentation Feeds Based on Rice-straw and Six Forage Crops on the Productivity of Holstein Cows (청예사료작물과 볏짚 위주의 완전배합발효사료 급여가 Holstein 착유우의 생산성에 미치는 영향)

  • Lee, H. J.;Kim, H. S.;Ki, K. S.;Jeong, H. Y.;Baek, K. S.;Kim, J. S.;Cho, K. K.;Cho, J. S.;Lee, H. G.;Woo, J. H.;Choi, Y. J.
    • Journal of Animal Science and Technology
    • /
    • v.45 no.1
    • /
    • pp.69-78
    • /
    • 2003
  • This experiment was carried out to evaluate the value of total mixed fermentation feeds(TMFF) as completely mixed ration and to observe the effect of various kinds of TMFF on the palatability, feed intake, and milk performance in Holstein cows. The dry matter (DM) content of TMFF used in the experiment was 23.98-28.42% range, and CP, TDN, ADF and NDF were 16.2${\sim}$19.2%, 58.3-65.1%, 34.4-39.6% and 46.9${\sim}$49.9% levels, respectively. The relative feed value (RFV) in rape-, alfalfa-, grass-, oat-, corn-TMFF groups were 138.6, 133.9, 116.5, 111.8, 111.4 and 108.1, respectively. Among these groups, RFV of rye-TMFF group was lowest. Dry matter disappearance(DMD) showed 0.8${\sim}$.9% to the all kinds of TMFF groups. The pH was 3.89${\sim}$.87 and $NH_3$-N concentration was 6.93-8.66 mg/$d\ell$. The acetic acid concentration in the raw material of TMFF showed low level of 0.19${\sim}$0.57%, lactic acid showed high level of 1.17${\sim}$3.21% and butyric acid was very high as 0.03${\sim}$0.32%. Therefore, these results provide evidence that the quality of TMFF was not so bad. In the daily fresh matter intake on the alfalfa-, grass-, rape-, corn-, oats- and rye-TMFF were showed 62.85, 60.48, 58.04, 57.11, 54.61 and 45.74 kg respectively. All TMFF showed high palatability as daily dry matter intake of 1.95 to 2.90% by body weight of experimental cows. Body condition score(BCS) was gradually increased in during 60 days of the experiment term. Average daily gain(ADG) showed about 140.0${\sim}$326.7g. In alfalfa-TMFF group, the ADG was higher than in the other groups (p<0.05). Also, the increase in BCS was observed in grass-TMFF group (3.07 to 3.34) and rye-TMFF group was decreased in 3.07 to 3.34 (p<0.05). The milk yield appropriately showed a range of 16.16${\sim}$18.95 kg in all groups. Among these groups, alfalfa-TMFF group was highest(P<0.05). Average milk fat contents showed high levels of 4.06${\sim}$4.79% and the level was high in order of rape-, grass-, corn-, alfalfa-, rye- and oats-TMFF. Milk protein was highest in forage-TMFF and level of lactose in milk was approximately 4.56% in overall groups. Solid non fat(SNF) and total solid(TS) contents were 8.75% and 12.8%, respectively. However, milk composition was not significantly affected by TMFF.

Studies on the Repeated Toxicity Test of Food Red No.2 for 4 Weeks Oral Administration in SD Rat (SD랫드에서 식용색소 적색2호의 4주간 경구투여에 따른 반복독성시험에 관한 연구)

  • Yoo, Jin-Gon;Jung, Ji-Youn
    • Journal of Food Hygiene and Safety
    • /
    • v.27 no.1
    • /
    • pp.42-49
    • /
    • 2012
  • This study was carried out to investigate the toxicity of food Red No.2 in the Sprague-Dawley (SD) female rat for 4 weeks. SD rats were orally administered for 28 days, with dosage of 500, 1,000, 2,000 mg/kg/day. Animals treated with food Red No.2 did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. There were not significantly different from the control group in urinalysis, hematological, serum biochemical value and histopathological examination. In conclusion, 4 weeks of the repetitive oral medication of food Red No.2 has resulted no alteration of toxicity according to the test materials in the group of female rats with injection of 2,000 mg/kg. Therefore, food Red No.2 was not indicated to have any toxic effect in the SD rats, when it was orally administered below the dosage 2,000 mg/kg/day for 4 weeks.

Evaluation of Reference Intervals of Some Selected Chemistry Parameters using Bootstrap Technique in Dogs (Bootstrap 기법을 이용한 개의 혈청검사 일부 항목의 참고범위 평가)

  • Kim, Eu-Tteum;Pak, Son-Il
    • Journal of Veterinary Clinics
    • /
    • v.24 no.4
    • /
    • pp.509-513
    • /
    • 2007
  • Parametric and nonparametric coupled with bootstrap simulation technique were used to reevaluate previously defined reference intervals of serum chemistry parameters. A population-based study was performed in 100 clinically healthy dogs that were retrieved from the medical records of Kangwon National University Animal Hospital during 2005-2006. Data were from 52 males and 48 females(1 to 8 years old, 2.2-5.8 kg of body weight). Chemistry parameters examined were blood urea nitrogen(BUN)(mg/dl), cholesterol(mg/dl), calcium(mg/dl), aspartate aminotransferase(AST)(U/L), alanine aminotransferase(ALT)(U/L), alkaline phosphatase(ALP)(U/L), and total protein(g/dl), and were measured by Ektachem DT 60 analyzer(Johnson & Johnson). All but calcium were highly skewed distributions. Outliers were commonly identified particularly in enzyme parameters, ranging 5-9% of the samples and the remaining were only 1-2%. Regardless of distribution type of each analyte, nonparametric methods showed better estimates for use in clinical chemistry compare to parametric methods. The mean and reference intervals estimated by nonparametric bootstrap methods of BUN, cholesterol, calcium, AST, ALT, ALP, and total protein were 14.7(7.0-24.2), 227.3(120.7-480.8), 10.9(8.1-12.5), 25.4(11.8-66.6), 25.5(11.7-68.9), 87.7(31.1-240.8), and 6.8(5.6-8.2), respectively. This study indicates that bootstrap methods could be a useful statistical method to establish population-based reference intervals of serum chemistry parameters, as it is often the case that many laboratory values do not confirm to a normal distribution. In addition, the results emphasize on the confidence intervals of the analytical parameters showing distribution-related variations.

Effects of Different Physical Frequency on Food-Dependent Exercise Induced Allergy Anaphylaxis (FDEIA) and Related Mechanisms (운동빈도의 차이가 식이유도 운동알레르기 질환과 관련기전에 미치는 영향)

  • Kim, Cheol-Woo;Kwak, Yi-Sub
    • Journal of Life Science
    • /
    • v.22 no.7
    • /
    • pp.897-903
    • /
    • 2012
  • Food allergies have become a serious health concern in the past two decades, especially in developed countries. Foods associated with allergies include vegetables, some fruits, shellfish, wheat, egg, chicken, and nuts. To describe the specific fundamentals, etiological factors, and clinical manifestations, we analyzed the different physical frequency on spleen index in sensitized and regular exercise-trained mice. We also conducted a proliferation assay of lymphocytes to OVA, ROS, ASAS, and we determined the cytokine levels. Female BALB/c mice were bred in the animal laboratory of the P and D university under controlled conditions ($22{\pm}2^{\circ}C$, RH 45-55%, and a 12-hour photoperiod). The animals were 6 weeks old at the start of the study and were fed a standard commercial chow diet from 09:00 to 15:00 for the 8-week study period. All animals had access to distilled deionized water ad libitum. They were divided into four groups: a control group (S; control sensitized, n=25), a low-frequency training group (F2, n=25), a mid-frequency training group (F3, n=25), and a high-frequency training group (F5, n=25) following the treatment of exercise time per week. The results were as follows: The mice spleen index showed the highest grade in the F5 group compared with the other groups; this level showed in an exercise frequency-dependent manner. In the proliferation assay of OVA, the F5 group showed the highest grade compared with the other groups; this level was also showed in an exercise frequency-dependent manner. Peritoneal ROS and ASAS showed a statistically significant increase in the F5 group and decreased in the F2 group compared with the S group. However, there were no significant differences in the F3 group. The highest level of IL-4 was found in the F5 group compared with the other groups. However, the highest level of INF-${\gamma}$ was in the F2 group. The results suggest that FDEIA is positively correlated with the frequency of exercise due to the direct effect of physical exercise on peritoneal ROS and the cytokine profile. Further research is needed on the specific mechanism underlying the combined effects of exercise intensity and frequency on physical-induced allergy anaphylaxis.

Oestrogenic Activity of Parabens in Uterotrophic Assay (자궁비대시험 연구에서 에틸, 프로필, 이소프로필, 부틸, 이소부틸 파라벤의 내분비독성)

  • Jo Eun-Hye;Jung Ji-Youn;Park Cheol-Beom;Park Sun-Hee;Shim Yhong-Hee;Kang Dae-Hyuck;Lee Sung-Ho;Yu Jong-Hoon;Kim Sun-Jung;Lee Sung-Hoon;Park Jung-Ran;Lee Yong-Soon;Kang Kyung-Sun
    • Journal of Food Hygiene and Safety
    • /
    • v.21 no.2
    • /
    • pp.118-128
    • /
    • 2006
  • This study was conducted to determination of the endocrine distruptor function of 'Parabens' by dosing ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben to the immature SD rats. 18 groups were given vehicle control group, negative control group (Dibutyl phthalate), postive control group ($1'7-{\alpha}$ Ethynylestrdiol) and each paraben groups involved 3 dose level. Rats were injected with 62.5, 250 and 1,000mg/kg from postnatal day 19 till 21 once a day in subcutaneous and a total 3, times. There was no treatment related death. but, subcutaneous nodule, edema, alopecia and scrub formation on injection site was observed. These signs was become worse in high dose level. these signs was cause from physical stimulation by test substance which parabens were mix with com oil as vehicle. In the analysis of organ weights, absolute and relative weights of brain, spleen, liver, thymus, heart, kidneys, adrenals, ovaries and vagina were no difference with control group. but, wet and blotted weight of uterus was increased in every high dose parabens treat group. Especially, all dose level of isobutyl paraben was showed increment of uterus weight. uterus dilatation of parabens treated group was observed in gross anatomic pathology and these result was agree with wet and blotted weight of uterus. In the result of this study, estrogenic effect as endocrine distruptor was observed in ethyl paraben, propyl paraben, isopropyl paraben, butyl paraben and isobutyl paraben. and it was considered isobutyl paraben has highest estrogrnic effect under the condition of this study.

On the High Yield Pulping of Fir by Pressurized Refining (가압(加壓)리화이닝법(法)에 의한 젓나무의 고수율(高收率)펄프 제조(製造)에 관한 연구(研究))

  • Cho, Nam Seok;Jo, Byoung Muk
    • Journal of Korean Society of Forest Science
    • /
    • v.53 no.1
    • /
    • pp.44-55
    • /
    • 1981
  • Neutral sulfite precooked fir chips were refined in the Asplund Laboratory Defibrator at various temperature ($20^{\circ}C$, $120^{\circ}C$ and $180^{\circ}C$). The effects of refining temperatures on the physical property and morphological structure of the resulting pulps were discussed. Yields of precooked chips (84%, 92% and 100%) and refining temperature affected remarkably the yield of refined pulp, its beatability, sheet strength and morhphological characteristics. Pulp yield and beatability decreased with increasing refining temperature. Fiber surface of unbeaten pulp from precooked chips of 84% yield was to some extent covered by the secondary wall, while that of the pulp form precooked yield of 92% by the compound middle lamella. In the case of uncooked chips, fibers were damaged heavily, and the exposed fiber surface resulted from the equal amount of the secondary wall and the compound middle lamella. In the case of pulps prepared from precooked chips of higher yields (92% and 100%), sheet strength increased linearly as sheet density increased. But at the same sheet density, pulp from lower precooked yield (84%) had better sheet strength after open discharge refining as compared to pressurized refining, because pulp from the former had much amounts of fines fraction of higher water retention value than the latters. And there was observed a little difference in fiber length distribution but nearly similar in its morphology with increasing refining temperature.

  • PDF

Review of the developmental trend of implant surface modification using organic biomaterials (생체활성 유기물로 표면이 개질된 임플란트 개발 추이 분석 연구)

  • Hwang, Sung-Taek;Han, In-Ho;Huh, Jung-Bo;Kang, Jeong-Kyung;Ryu, Jae-Jun
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.49 no.3
    • /
    • pp.254-262
    • /
    • 2011
  • Purpose: This study aims to evaluate and prospect for current research trend and developmental perspectives via analyzing recent biomaterial coated-implants study. Materials and methods: To investigate each subject respectively, several biomaterials that are using for implant surface coating were set as 'keywords'. By these keywords, major research groups in each subject were chosen, and research trend of them was analyzed. Trend of In vivo studies that examined selected biomaterials were analyzed to evaluate commercial potential. Results: The collagen research accounted for 40% of total implant study, which was the highest, and fibronectin, BMPs (bone morphogenetic proteins) and RGD (Arg-Gly-Asp) peptides followed, which were ranked in descending order. Furthermore, figures of all four research subjects were also increased with time, especially a sharp increase in RGD research. According to the results of major research group, collagen that was combined with other organic and inorganic biomaterials was mostly examined, rather than using collagen only. Major research groups investigating BMPs mostly focused on rhBMP-2. In animal studies, collagen was used as resorbable membrane in guided bone regeneration (GBR) or drug carrier, while BMPs were used with bone graft materials or coating material for titanium implant surface. Conclusion: There is not consistency of results even in identical subjects research field. Many studies are ongoing to optimize combination between mechanical surface treatment and biomaterials such as extracellular matrix component and growth factors.

Microbe Hunting: A Curious Case of Cryptococcus

  • Bartlett, Karen H.;Kidd, Sarah;Duncan, Colleen;Chow, Yat;Bach, Paxton;Mak, Sunny;MacDougall, Laura;Fyfe, Murray
    • Proceedings of the Korean Environmental Health Society Conference
    • /
    • 2005.06a
    • /
    • pp.45-72
    • /
    • 2005
  • C. neoformans-associated cryptococcosis is primarily a disease of immunocompromised persons, has a world-wide distribution, and is often spread by pigeons in the urban environment. In contrast, C. gattii causes infection in normal hosts, has only been described in tropical and semi-tropical areas of the world, and has a unique niche in river gum Eucalyptus trees. Cryptococcosis is acquired through inhalation of the yeast propagules from the environment. C. gattii has been identified as the cause of an emerging infectious disease centered on Vancouver Island, British Columbia, Canada. No cases of C. gattii-disease were diagnosed prior to 1999; the current incidence rate is 36 cases per million population. A search was initiated in 2001 to find the ecological niche of this basidiomycetous yeast. C. gaftii was found in the environment in treed areas of Vancouver Island. The highest percentage of colonized-tree clusters were found around central Vancouver Island, with decreasing rates of colonization to the north and south. Climate, soil and vegetation cover of this area, called the Coastal Douglas fir biogeoclimatic zone, is unique to British Columbia and Canada. The concentration of airborne C. gattii was highest in the dry summer months, and lowest during late fall, winter, and early spring, months which have heavy rainfall. The study of the emerging colonization of this organism and subsequent cases of environmentally acquired disease will be informative in planning public health management of new routes of exposure to exotic agents in areas impacted by changing climate and land use patterns. Cryptococcosis is an infection associated with an encapsulated, basidiomycetous yeast Cryptococcus neoformans. The route of entry for this organism is through the lungs, with possible systemic spread via the circulatory system to the brain and meninges. There are four cryptococcal serogroups associated with disease in humans and animals, distinguished by capsular polysaccharide antigens. Cryptococcus neoformans: variety grubii (serotype A), variety neoformans (serotype D), and variety gattii (serotypes B and C) (Franzot et at. 1999). C. neoformans variety gattii has recently been elevated to species status, C. gattii. C. neoformans val. grubii and var. neoformans have a world-wide distribution, and are particularly associated with soil and weathered bird droppings. In contrast, C. gattii (CG) is not associated with bird excrement, is primarily found in tropical and subtropical climates, and has a restricted environmental niche associated with specific tree species. (Ellis & Pfiffer 1990) Ellis and Pfeiffer theorize that, as a basidiomycete, CG requires an association with a tree in order to become pathogenic to mammals. In Australia, CG has been found to be associated with five species of Eucalypts, Eucalyptus camaldulensis, E. tereticornis, E. blakelyi, E. gomphocephala, and E. rudis. Eucalypts, although originally native to Australia, now have a world-wide distribution. CG has been found associated with imported eucalypts in India, California, Brazil, and Egypt. In addition, in Brazil and Columbia, where eucalypts have been naturalized, native trees have been shown to harbour CG (Callejas et al. 1998; Montenegro et al. 2000). In British Columbia, Canada, since the beginning of 1999, there have been 120 confirmed cases of cryptococcal mycoses associated with CG in humans, including 4 fatalities (data from British Columbia Centre for Disease Control), and over 200 cases in animal pets in BC (data from Central Laboratory for Veterinarians). What is remarkable about the BC outbreak of C. gattii-cryptococcosis is that all of the cases have been residents of, or visitors to, a narrow area along the eastern coast of Vancouver Island, BC, from the tip of the island in the south (Victoria) to Courtenay on the north-central island as illustrated in Figure 1. Of the first 38 human cases, 58% were male with a mean age of 59.7 years (range 20 - 82): 36 cases (95%) were Caucasian. Ten cases (26%) presented with meningitis, the remainder presented with respiratory symptoms. Cultures recovered from cases of cryptococcosis associated with the outbreak were typed as serogroup B, which is specific to CG (Bartlett et al. 2003). This was the first reported outbreak of CVG in Canada, or indeed, the world. Where infection with CG is endemic, for example, Australia, the incidence of cryptococcosis ranges from 1.8 - 4.7 per million between the southern and northern states (Sorrell 2001). However, the overall incidence of cryptococcosis in immunocompenent individuals has been estimated at 0.2 per million population per year (Kwon-Chung et al. 1984). The population of Vancouver Island is approximately 720,000,consequently, even if the organism were endemic, one would expect a maximum of 0.15 cases of cryptococcal disease annually.

  • PDF

Effect of Recombinant CagL Immunization on the Gastric Diseases Induced by Helicobacter pylori in Mongolian gerbils (CagL 재조합 단백질 접종후에 Mongolian gerbil에서 나타나는 Helicobacter pylori 감염에 대한 반응)

  • Bak, Eun-Jung;Jang, Sung-Il;Choi, Yun-Hui;Kim, Jin-Moon;Kim, Ae-Ryun;Kim, Ji-Hye;Woo, Gye-Hyeong;Yoo, Yun-Jung;Lee, Sung-Haeng;Cha, Jeong-Heon
    • Korean Journal of Microbiology
    • /
    • v.48 no.2
    • /
    • pp.109-115
    • /
    • 2012
  • Helicobacter pylori is an important factor of chronic gastritis, digestive ulcer, and stomach cancer. CagL, a virulence factor of H. pylori, is well-known as a pilus protein which acts as adhesion to host cell and a component of Type 4 secretion system. In this study, we evaluated the protective response of recombinant CagL protein (rCagL) using Mongolian gerbil animal model for H. pylori infection. The cagL gene was cloned from 26695 H. pylori followed by over-expression and purification of the protein in E. coli. Mongolian gerbils were immunized with rCagL protein mixed with aluminum adjuvant via intramuscular injections once a week during 4 weeks. At a week after the last immunization, the Mongolian gerbils were administrated with H. pylori 7.13 strain into the stomach and sacrificed to measure antibody titer on rCagL by ELISA and bacterial colonization in the stomach, and to examine the histopathological changes and cytokine expression at 6 week after challenge. Antibody titers on recombinant protein were significantly increased from a week after the first immunization. There was no significant change of the number of bacterial colony between control group and immunized group. The relative stomach weight was significantly decreased in immunized group, but the significant change of histopathological assessment was not observed in the stomach. Cytokine expression such as IL-$1{\beta}$ and KC also was not significantly different between control and immunized groups. These results indicate that rCagL could effectively induce the formation of the specific IgG antibodies. However, bacterial colonization and histopathological lesions could not be inhibited by the immunization in the stomach, indicating not enough protection against H. pylori infection. We consider that along with CagL other adequate antigens could be needed stimulating immune response and inducing protective effects against gastric disease, and also a better adjuvant could be considered.