• 제목/요약/키워드: Assay sensitivity

검색결과 756건 처리시간 0.03초

한냉적응이 Adenyl Cyclase Activity에 미치는 영향 (Adenyl Cyclase Activity in Cold-acclimatized Animals)

  • 강복순;이상호;강두희
    • The Korean Journal of Physiology
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    • 제8권2호
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    • pp.67-74
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    • 1974
  • The object of this research is aimed to determine the activity of adenyl cyclase in both skeletal muscle sarcolemma and fat cell ghost of epididymal adipose tissue isolated from rats exposed to cold for various length of time in an attempt to evaluate whether the tissue sensitivity to catecholamine is increased when rats are exposed to cold for long periods of time Methods: a)Animals: Albino rats ranging in weight from 150 to 200 gm were used throughout this study. For experimental purposes, the rats are divided into two groups: experimental animals were place4 in a cold room at $4^{\circ}C$, controls being kept at $25^{\circ}C$. At the end of 2, 4, 6, 12, and 16 weeks. exposure to cold the rats were used to measure the adenyl cyclase activity. b) Isolation of plasma membrane from skeletal muscle and adipose tissue: The Plasma membrane of skeletal muscle from hind limbs of rats are prepared by the method employed by Rosenthal et at. and fat cell ghost of epididymal adipose tissue of rats by the method employed by Rodbell. c) Adenyl cyclase assay: Adenyl cyclase activity were measured by the method employed by Marinetti et al. Briefly, plasma membrane was incubated with $3^H-ATP$, various amount of noradrenaline and other incubation mixture at $37^{\circ}C$ for 20 minutes. After stopping the enzyme reaction by immersion in boiling water, carrier 3',5'-AMP was added to the system as a marker and $100\;{\mu}1$ aliquots of incubation mixture were pipetted on $20{\time}20$ Whatman No. 3 MM filter paper for one dimensional chromatography. The cyclic AMP spots were cut off and placed in counting vials containing 10ml of Bray's scintillation cocktail. Radioactivity was determined with a Packard Tri-Carb liquid scintillation counter. The enzyme activity is expressed as nanomoles of cyclic AMP produced per mg of membrane per hour. Result: 1. Average adenyl cyclase activity in the plasma membrane of skeletal muscle before and after noradrenaline administration was significantly higher in the cold-exposed rats as compared to the control. Continuous exposure to cold Produced an increased adenyl cyclase activity before and after noradrenaline administration. Adenyl cyclase activity reached peak levels at the 6 weeks exposure to told and level of adenyl cyclase activity remained high. Noradrenaline administration to the incubation medium induced a significant increase in adenyl cyclase activity and the degree of stimulation were proportional to the hormonal concentration But the rate of inclement in adenyl cyclase activity by noradreasline was the same in both groups. 2. Adenyl cyclase activity in fat cell ghost between cold exposed and control rats showed no significant differences before and after noradreualine administration. In summary, it can be concluded that cold adaptation give rise an increased activity of adenyl cyclase in plasma membrane of skeletal muscle in rats.

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Robust Reference Intervals for Serum Kappa and Lambda Free Light Chains from a Multi Centre Study Population from Hyderabad, India: Myeloma Diagnostic Implications

  • Mohammed, Noorjahan;Chandran, Priscilla Abraham;Kandregula, Madhavi;Mattaparthi, Ratna Deepika;Gundeti, Sadasivudu;Volturi, Jyotsna;Darapuneni, Radhika;Raju, Sree Bhushan;Dattatreya, Palanki Satya
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권5호
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    • pp.2605-2610
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    • 2016
  • The International Myeloma Working Group considers the serum free light chain (SFLC) assay to be an adjunct to traditional tests. Apart from the FLC ratio, the absolute values of individual free light chains also are gaining importance as they appear to be more relevant in certain clinical settings. Automated assays are available for their determination. As laboratories put new test systems into use catering to different disease populations, they are required by accreditation and certification bodies to verify or establish performance specifications, including reference intervals (RIs) representative of their population. Our aim was to establish local RIs for SFLC in a multicentre representative healthy population using a robust method. There was no significant relationship between SFLC levels and age, gender and creatinine levels. The 95% RI for ${\kappa}SFLC$ was 4.81 to 33.86mg/L, for ${\lambda}$ SFLC was 5.19 to 23.67mg/L and for ${\kappa}/{\lambda}SFLC$ was 0.36 to 2.33, significantly higher than the values given by the manufacturer. The ${\kappa}/{\lambda}$ SFLC ratio at 2.23, covering 100% of the data, showed 72% sensitivity (95% CI=39.0 - 94.0), 100% specificity (95% CI=71.5 - 100.0), 100% PPV (95% CI=21.5 - 100.0), 95% NPV (95% CI=75.4 - 99.9), and 79% accuracy (95% CI=56.0 - 93.0). In the patient group, kit RI for ${\kappa}/{\lambda}$ SFLC ratio classified 45.5% (n=5) as positive vs 9.1% (n=1) positive by the study RI, while the kit RI for kappa FLC classified 90.9% (n=10) as positive vs 54.5% (n=6), indicating increased probability of false positive test results with the kit RI when applied to our patient population. Appropriate and specific reference intervals and criteria values result in fewer false-positive and false-negative results which means fewer wrong or missed diagnoses.

Cloning of porcine chemerin, ChemR23 and GPR1 and their involvement in regulation of lipogenesis

  • Huang, Jianfeng;Zhang, Jian;Lei, Ting;Chen, Xiaodong;Zhang, Yan;Zhou, Lulu;Yu, An;Chen, Zhilong;Zhou, Ronghua;Yang, Zaiqing
    • BMB Reports
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    • 제43권7호
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    • pp.491-498
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    • 2010
  • Chemerin is a novel adipokine which is abundant in adipose tissue to promote adipocyte differentiation and with significant relativity to BMI and insulin sensitivity. We report here the molecular characterization of porcine chemerin and its receptors ChemR23 and GPR1, as well as their transcriptional regulation during lipogenesis. Chemerin was mainly expressed in liver, intestine, kidney and adipose tissue, consistent with the expression pattern of GPR1, but not ChemR23, which was predominantly present in spleen and temperately in adipose tissue. We further investigated the lipogenesis-related transcriptional activation of $PPAR{\gamma}$ and KLF15 on chemerin and its receptors. The data showed that KLF15, but not $PPAR{\gamma}$, can up-regulate the mRNA level of chemerin, ChemR23 and GPR1, which was consistent with the results of luciferase assay that confirmed the effect of KLF15 on ChemR23 promoter. Taken together, our data provide basic molecular information for the further investigation on the function of chemerin in lipogenesis.

항 Pseudomonas tolaasii 및 Pseudomonas agarici 항체의 면역측정법을 위한 평가와 그 이용 (Evaluation of the antibodies against Pseudomonas tolaasii and Pseudomonas agarici for Immunoassays and Its Application)

  • 전낙범;이향범;손동화;유승헌
    • 식물병연구
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    • 제9권2호
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    • pp.94-98
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    • 2003
  • 느타리버섯에 발생하여 갈색부패병을 일으키는 P. tolaasii 및 P.agarici 를 면역화학적 방법으로 신속하게 검출하기 위한 항체를 생산하였고 면역확산법과 ELISA 로 본 항체의 특이성을 조사하였다. $\alpha$-P tolaasii 항체는 P. tolaasii와 반응하여 선명한 침강선을 형성하지 않아 P. tolaasii 에 대하여만 특이적으로 반응하는 항체임을 알 수 있었다. 한편 $\alpha$-P. agarici 항체는 P.agarici뿐만 아니라 다른 세균에 대해서도 침강선을 형성하지 않는 특징을 나타내었다. 비경합 간접 ELISA의 표준곡선으로부터 P.agarici의 검출에 대하여 최고 발색치의 50% 갑을 나타내는 균의 밀도는 $2{\times}10^4$ cfu/ml로 나타났으며, 검출한계농도는 $2{\times}10^3$ cfu/ml 이었다.${\alpha}$-P. agarici 항체는 P. tolaasii의 특이적인 검출에도 효과를 나타냈다. ${\alpha}$-P. tolaasii, ${\alpha}$-P. agarici 항체를 이용하여 확립한 ELISA법은 직접 균체나 버섯 자실체내 P. tolaasii 와 P. agarici의 신속한 검출을 가능하게 하였고, P. tolaasii 와 P. agarici에 오염된 시료를 간단하게 진단하는데 아주 유용하게 사용될 수 있을 것으로 판단되었다.

Quantitative PCR for Etiologic Diagnosis of Methicillin-Resistant Staphylococcus aureus Pneumonia in Intensive Care Unit

  • Kwon, Sun-Jung;Jeon, Tae-Hyeon;Seo, Dong-Wook;Na, Moon-Joon;Choi, Eu-Gene;Son, Ji-Woong;Yoo, Eun-Hyung;Park, Chang-Gyo;Lee, Hoi-Young;Kim, Ju-Ock;Kim, Sun-Young;Kang, Jae-Ku
    • Tuberculosis and Respiratory Diseases
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    • 제72권3호
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    • pp.293-301
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    • 2012
  • Background: Ventilator-associated pneumonia (VAP) requires prompt and appropriate treatment. Since methicillin-resistant Staphylococcus aureus (MRSA) is a frequent pathogen in VAP, rapid identification of it, is pivotal. Our aim was to evaluate the utility of quantitative polymerase chain reaction (qPCR) as a useful method for etiologic diagnoses of MRSA pneumonia. Methods: We performed qPCR for mecA, S. aureus-specific femA-SA, and S. epidermidis-specific femA-SE genes from bronchoalveolar lavage or bronchial washing samples obtained from clinically-suspected VAP. Molecular identification of MRSA was based on the presence of the mecA and femA-SA gene, with the absence of the femA-SE gene. To compensate for the experimental and clinical conditions, we spiked an internal control in the course of DNA extraction. We estimated number of colony-forming units per mL (CFU/mL) of MRSA samples through a standard curve of a serially-diluted reference MRSA strain. We compared the threshold cycle (Ct) value with the microbiologic results of MRSA. Results: We obtained the mecA gene standard curve, which showed the detection limit of the mecA gene to be 100 fg, which corresponds to a copy number of 30. We chose cut-off Ct values of 27.94 (equivalent to $1{\times}10^4$ CFU/mL) and 21.78 (equivalent to $1{\times}10^5$ CFU/mL). The sensitivity and specificity of our assay were 88.9% and 88.9% respectively, when compared with quantitative cultures. Conclusion: Our results were valuable for diagnosing and identifying pathogens involved in VAP. We believe our modified qPCR is an appropriate tool for the rapid diagnosis of clinical pathogens regarding patients in the intensive care unit.

Erythropoietin 검사법(檢査法)에 관(關)한 연구(硏究) (Studies on Erythropoietin Bioassay Method)

  • 조경삼;노흥규;이문호
    • 대한핵의학회지
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    • 제9권2호
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    • pp.39-46
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    • 1975
  • It is the purpose of this paper to design the most preferable method of erythropoietin bioassay in Korea. Bioassay utilizing polycythemic mice are currently in general use for the indirect determination of erythropoietin. Assay animals are usually prepared either by transfusion or by exposure to reduced oxygen tension in specially constructed chamber. We prepared the polycythemic, mice by the specially constructed hypobaric chamber. We observed weights and hematocrits of the mice in the hypobaric chamber, then hematocrits and 72 hours $^{59}Fe$ red cell upatke ratio of the polycythemic mice induced by hypoxia after removal from the hypobaric chamber. We designed the method of erythropoietin bioassay according to the results obtained by above experiments. Then we measured the 72 hours $^{59}Fe$ red cell uptake ratio of the polycythemic mice with normal saline, normal plasma and anemic plasma according to the method we designed. The results are followed: 1. The hematocrits of the mice in hypobaric chamber increased to 74% in 14 days It is preferable to maintain the pressure of the chamber to 400mmHg for first 4 days then 300mmHg for last 10 days to reduce the death rate and time consuming in hypobaric chamber. 2. After removal from the hypobaric chamber, the 72 hours $^{59}Fe$ red cell uptake ratio decreased rapidly and maintained the lowest level from the fourth day to tenth day. 3. We design the method of erythropoietin bioassay according to the results of above experiment and to the half life of erythropoietin. 4. The Korean product S9Fe is mixture of $^{59}Fe\;and\;^{55}Fe$. And the $^{59}Fe$ red cell uptake ratio in normal mice was far less with Korean product $^{59}Fe$ than with pure $^{59}Fe$ of foreign product. So it is desirable to use pure $^{59}Fe$ in this method of erythropoietin bioassay. 5. Considering the cost, the technique, the time consuming and the sensitivity it is the most preferable method of erythropoietin bioassay in Korea using hypobaric chamber to induce the polycythemia.

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다양한 식품에서 Campylobacter jejuni 검출을 위한 real-time PCR과 배지배양법의 비교검증 (Comparison of Real-Time PCR and Culture Methods for Detection of Campylobacter jejuni in Various Foods)

  • 천정환;현지연;황인균;곽효선;한정아;김무상;김종현;송광영;서건호
    • 한국식품과학회지
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    • 제43권1호
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    • pp.119-123
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    • 2011
  • 본 연구에서는 두 종류의 선택배지를 활용한 배지배양법과 realtime PCR의 C. jejuni 검출능력을 비교하였다. 소시지, 쇠고기 분쇄육, 무순에 C. jejuni를 접종하고 Hunt broth로 증균배양 하였으며, mCCD agar와 Preston agar에 배양액을 획선도말하여 미호기적으로 배양하였다. 동시에 증균배양액에서 1 mL을 채취하여 realtime PCR을 실시하였다. 실험결과, real-time PCR은 쇠고기 분쇄육과 소세지에서 두 가지 선택배지와 비교하여 동일한 검출력을 보였으나 무순에서는 훨씬 더 많은 양성을 검출하였다(p<0.05). 두 배지간의 비교에서는 Preston agar와 mCCD agar는 통계학적 유의차가 없는 민감도를 보였다(p>0.05). 결론적으로 real-time PCR은 표준검출법인 배지배양법과 비교하여 동등하거나 우수한 민감도를 지닌 신속검출기법인 것으로 사료되며, 배지배양법에 앞서 선별검사로 사용할 경우 시간, 비용, 노동력 절감에 있어서 매우 유효한 방법이 될 것으로 판단된다.

방사선 치료에 내성이 유도된 두경부 편평세포암에 대한 종양살상 헤르페스 바이러스의 유전자 치료 효과 (Therapeutic Effect of Oncolytic Herpes Simplex Virus on Induced Radioresistant Head and Neck Squamous Cell Carcinoma)

  • 김세헌;최은창;이진석;천제영;변형권;송기재;김광문
    • 대한두경부종양학회지
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    • 제22권2호
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    • pp.130-136
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    • 2006
  • Introduction : The sensitivity of tumor cells to radiotherapy is a critical determinant of local control and potential cure in advanced head and neck squamous cell carcinoma(HNSCC). The emergence of radioresistant tumor cells is an obstacle to cancer therapy. Most radioresistant cells have a higher proportion of cells in the Sphase of the cell cycle and a lower apoptotic fraction than radiosensitive cells. HSV replication is increased in cells that have higher S-phase fractions. NV1066 is an oncolytic herpes simplex virus type-1 mutant. We hypothesized that NV1066 replication and cytotoxicity are increased in radioresistant cells. The purpose of this study is to evaluate the antitumor efficacy of NV1066 to treat radioresistant HNSCC. Methods : Radioresistant cells were selected by treating five HNSCC cell lines with repeated conventional fractionated doses of radiation(2Gy/day), using a Cs-137 irradiator, up to a cumulative dose of 70Gy. Clonogenic cell survival and S-phase fractions were compared between radioresistant and parental radiosensitive cells. The two cell populations were then treated with NV1066 to examine viral replication, by the viral plaque assay and viral cytotoxicity. Results : Fractionated irradiation resulted in the selection of radioresistant cells. Radioresistant cells had a higher S-phase fraction(42.9%) compared to parental cells(26.2%). NV1066 replication in radioresistant cells was 7.4 times higher than in parental cells(p<0.01). Treatment with NV1066 resulted in increased cytotoxicity of 24.5% in radioresistant cells compared to parental cells(p<0.05). Conclusion : NV1066 showed increased viral replication and cytotoxicity in radioresistant HNSCC cell lines. These findings suggest a potential clinical application for this oncolytic viral therapy as treatment for radioresistant head and neck cancers.

Thyrogen 투여 후 측정된 Thyroglobulin 농도변화 (The Variation of Serum Thyroglobulin Measured after Thyrogen Administration)

  • 김지나;안재석;원우재
    • 핵의학기술
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    • 제22권1호
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    • pp.80-83
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    • 2018
  • Purpose Assessment of Serum Thyroglobulin (sTg) value in total thyroidectomy patients having an ablation dose of radioactive iodine indicates remaining cancer or metastasis. Especially, sTg in patients on withdrawal thyroxine or thyrogen administration for radioiodine ablation is an important indicator to determine the direction of further treatment and prognosis. Current guidelines suggest measurement of sTg is performed at 72 hours after the last injection of thyrogen. and assumes that sTg reaches maximum serum levels at that time. The purpose of this study is to evaluate the variation of sTg measured after thyrogen administration. Materials and Methods We compared with sTg performed at 24hours(D0) and 72hours(D2) after the last injection of thyrogen. We reviewed D0 and D2 from 276 patients were divided them into three groups according to ablation dose of radioactive iodine, 5mCi(A group), 30~80mCi(B group) and 100~200mCi(C group). We used T-test for comparison between D0 and D2. sTg was measured in serum using immunoradiometric assay (Tg-plus RIA; BRAHMS, Berlin, Germany). Results There is no critical variation between D0 and D2 in A group(n=100)(P=0.32), The case of increase(D2>D0) is 45, no change(D2=D0) is 23, decrease(D2D0 is 91, D2=D0 is 28, D2D0 is 19, D2=D0 is 2. The biggest increase is 143.6 ng/mL from 98.4 to 242. Conclusion There was a significant difference in the group over 30mCi. and the case of D2>D0 is 45%, 58.7%, 90.5% for each group. therefore, D2 increased as the dose of radioactive iodine increased. Furthermore, the most sTg values of D0 and D2 are variation under 2.0 ng/mL, so reproducibility as well as sensitivity of sTg will be important at values below 2ng/mL.

국내 맥류에 발생하는 바이러스병 동시진단 방법 (Simultaneous Detection of Barley Virus Diseases in Korea)

  • 이봉춘;배주영;김상민;나지은;최낙중;최만영;박기도
    • 식물병연구
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    • 제23권4호
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    • pp.363-366
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    • 2017
  • 최근 국내 맥류 재배지에서는 대부분 BaMMV, BaYMV, BYDV의 발생이 확인되고 있다. 본 연구에서는 multiplex reverse transcription polymerse chain reaction (mRT-PCR) 방법에 의해 이들 3종류의 바이러스를 동시에 진단하는 방법을 확립하였다. 이들 3종 바이러스의 외피단백질 유전자 정보를 활용하여 각 바이러스에 대한 primer를 제작하였다. mRT-PCR에 사용한 primer는 RT-PCR 반응의 민감도와 특이성에 의해 선발하여 primer 농도와 mRT-PCR의 조건을 설정하였다. 각 바이러스에 대하여 선발된 primer 사용에 의한 mRT-PCR 결과 BaMMV 594 bp, BaYMV 461 bp, BYDV 290 bp의 PCR 산물을 얻을 수 있었다. 본 연구에서 확립된 맥류 바이러스 동시진단방법은 신속하고 특이적인 진단 뿐 아니라 맥류 바이러스병의 전염 등 역학 연구에도 활용 될 것으로 기대된다.