• Title/Summary/Keyword: In vivo detection

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Production and Characterization of a Recombinant Antibody Neutralizing Botulinum Neurotoxin A (보툴리눔 신경독소 A를 중화하는 재조합 항체의 제조와 특성 분석)

  • Park, Hong-Gyu;Choi, Mieyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.295-301
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    • 2017
  • Botulinum neurotoxin (BoNT/A) is a neurotoxin that selectively attacks the peripheral cholinergic nerve endings. It is produced by Gram -positive, endospore-forming strict anaerobic bacteria, Clostridium botulinum. Since BoNT/A could be a biothreat agent, as well as a contaminator of food and water supplies, the development of sensitive assays for toxin detection and potent antitoxin for the treatment of intoxication is necessary. In this study, for the purpose of producing monoclonal antibodies (mAbs) that are capable of neutralizing Botulinum neurotoxin type A (BoNT/A), scFv (single-chain variable domain fragment) libraries from the rabbit antisera against BoNT/A was fused to a human IgG. The resulting recombinant scFvIgG antibody protein was expressed in stable cell lines and was purified using a protein A affinity chromatography. The efficacy of scFvIgG mAb was confirmed by ELISA and was evaluated for the neutralization of BoNT/A in vivo. Such an in vivo toxin neutralization assay was performed using mice. Although scFvIgG antibody proteins (10 ug) failed to fully protect the mice challenged with BoNT/A (100,000 $LD_{50}$), it significantly prolonged the survival time. These results suggest that scFvIgG mAb may be capable of neutralizing BoNT/A single-chain variable domain fragment.

Heme Oxygenase Expression in Skin of Hairless Mouse Using Ultraviolet A (320-400 nm) Radiation as an Inducer

  • Munif Allanson;Reeve, Vivienne-E
    • Journal of Photoscience
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    • v.9 no.3
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    • pp.33-36
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    • 2002
  • This study describes RT-PCR and in situ hybridisation protocols, and the immunohistochemical detection method that we have developed to detect and localise cells that express HO-1 in the skin. We found that HO-1 mRNA was absent in normal mouse skin, but after UVA irradiation HO-1 mRNA was expressed in the dermal fibroblasts, and strongly in basal epidermal cells. HO-1 protein was also induced strongly in dermal fibroblasts, and also in epidermal cells. In addition, the HO substrate heme was reduced in skin microsome at 72 hrs post UVA (when HO activity is high). At the same time, the HO products bilirubin and iron levels were elevated in the cutaneous tissue. Thus in addition to a dermal response, there appears to be an epidermal HO response to UVA in vivo that may be relevant for immune modulation by UVA radiation.

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Serum bactericidal activity and disposition kinetics of enrofloxacin in Korean native goats (한국재래산양에서 Enrofloxacin의 혈청내 항균효과와 체내동태)

  • Yun, Hyo-in;Kim, Moo-youl;Park, Seung-chun
    • Korean Journal of Veterinary Research
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    • v.37 no.2
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    • pp.321-330
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    • 1997
  • Enrofloxacin is one of the second-generation quinolones which have been widely used to treat bacterial infections in various species including chicken, pig, horse and cattle. The objective of the present study was to describe the serum bactericidal activity(SBA) of enrofloxacin, its pharmacokinetic behaviors after intramuscular or intravenous administration to Korean native goats in the dose rate of 5mg/kg b.w. The results obtained through this study were as follows : 1. Sera collected from both sexes of Korean native goats administered 5mg/kg i.v. or i.m. showed potent antibacterial activities up to the 12 hours by way of the serum bactericidal activity. 2. Concentrations of enrofloxacin in the biological samples were measured by high-performance liquid chromatography(HPLC) so as to study pharmacokinetic characteristics. For detection of enrofloxacin, 10% TCA was optimal for protein precipitation and the mobile phase was 0.01M citric acid/methanol/acetonitrile(7/2/1, pH 3.5) with solid phase being the $C_{18}$ reversephase column and detection wavelength being 278nm. The limit of detection of enrofloxacin on HPLC was $0.05{\mu}g/ml$. 3. Pharmacokinetic profile of enrofloxacin administered 5mg/kg i.v. in Korean native goats was best described by two-compartment open model and that administered i.m. the same rate by one-compartment model. There were no sex differences in pharmacokineticl parameters. In conclusion, enrofloxacin showed potent in vivo antibacterial activity and excellent pharmacokinetic properties in Korean native goats, hence it may be used as a potential antibacterial in the veterinary clinical settings.

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5-Aminolevulinic Acid Fluorescence in Detection of Peritoneal Metastases

  • Yonemura, Yutaka;Canbay, Emel;Ishibashi, Haruaki;Nishino, Eisei;Endou, Yoshio;Sako, Shouzou;Ogura, Shun-Ichirou
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.2271-2275
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    • 2016
  • Background: The value of 5-aminolevulinic acid (ALA) in fluorescence detection of peritoneal metastases and the underlying mechanisms were evaluated in patients with peritoneal surface malignancies. Materials and Methods: Oral 5-ALA was administered at a concentration of 20 mg/kg body weight with 50 ml of water 2 hours prior to surgery (n=115). The diagnostic value of 5-ALA based fluorescence production was evaluated following white light inspection during prior to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Then, peptide transporter PEPT1 (ALA influx transporter) and ATP-binding cassette transporter ABCG2 (porphyrin efflux transporter) gene expression was determined with quantitative real time (qRT)-PCR and pathological diagnoses confirmed for all tissue samples. Results: The 5-ALA based photodynamic detection rate was 17% for appendiceal mucinous neoplasms, 54% for colorectal cancers, 33% for gastric cancers, 67% for diffuse malign peritoneal mesotheliomas, and 89% for epithelial ovarian cancer of peritoneal metastases. 5-ALA was detected in all cases of peritoneal metastases originating from cholangiocarcinomas whereas it was not able to detect any in granulosa cell and gastrointestinal stromal tumor cases. Furthermore, PEPT1 was overexpressed whereas ABCG2 expression was downregulated in tumors detected with fluorescence. Conclusions: 5-ALA provided 100% specificity and high sensitivity to detect peritoneal metastases in subgroups of patients with peritoneal surface mailgnancies. ALA influx transporter PEPT1 and porphyrin efflux transporter ABCG2 genes are important in tumor specific 5-ALA induced fluorescence in vivo. Further studies should clarify diagnostic utility of 5-ALA in peritoneal surface malignancies.

Recent Development in Biocompatible Biosensors

  • Yongju Lee;Swarup Biswas;Minsuk Koo;Hyeok Kim
    • Journal of Sensor Science and Technology
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    • v.32 no.6
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    • pp.403-411
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    • 2023
  • The shift in the medical paradigm from treatment to prevention and diagnosis has underscored the growing significance of biosensors. Notably, the recent COVID-19 pandemic has spurred the widespread adoption of biosensors for the detection of viral genes and antigens. Consequently, there has been a substantial increase in both the demand for biosensors and the industries associated with their production. Furthermore, biosensors find applications not only in healthcare but also in diverse fields such as environmental monitoring, food quality control, military defense, and industrial processes. In this brief review, we delve into the essential attributes of biosensors, namely sensitivity, selectivity, and stability. We provide an overview of the latest research trends aimed at improving these attributes. Additionally, we introduce recent research cases in which these attributes are being applied both in vivo and in vitro.

Genetic Toxicity Studies of YH1226, a Cephalosporin Antibiotic (세파계 항생제, YH1226의 유전독성 평가)

  • 허광원;오혜영;박장환;허옥순;순수정;한의식;김명희;강희일
    • Environmental Mutagens and Carcinogens
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    • v.18 no.2
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    • pp.89-92
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    • 1998
  • The results of chromosome aberration test in mammalian cells in culture (Chinese hamster lung fibroblast cells) showed no induction of structural and numerical aberrations by YH1226, a cephalosporin antibiotic regardless of metabolic activation, while positive control group (mitomycin C and benzo(a)pyrene) showed structural chromosome aberrations of 25% and 10%, respectively. The in vivo induction of micronuclei was measured in polychromatic erythrocytes in bone marrow of male ddY mouse given YH1226 at 500, 250, 125 mg/kg by i.p. once. After 24 hours, animals were sacrificed and evaluated for the incidence of micronucleated polychromatic erythrocytes in whole erythrocytes. Although a positive response for induction of micronuclei in animals treated with mitomycin C demonstrated the sensitivity of the test system for detection of a chemical clastogen, YH1226 did not induce microunclei in bone marrow of ddY male mice.

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Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth

  • Kamburoglu, Kivanc;Sonmez, Gul;Berktas, Zeynep Serap;Kurt, Hakan;Ozen, Dogukan
    • Imaging Science in Dentistry
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    • v.47 no.2
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    • pp.109-115
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    • 2017
  • Purpose: The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth. Materials and Methods: Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The other 26 intact teeth that did not have caries served as controls. Teeth were imaged using a $100{\times}90-mm$ field of view and a 0.2-mm voxel size with 9 different CBCT settings. Four observers assessed the images using a 5-point scale. Kappa values were calculated to assess observer agreement. CBCT settings were compared with the gold standard using a receiver operating characteristic analysis. The area under the curve (AUC) values for each setting were compared using the chi-square test, with a significance level of ${\alpha}=.05$. Results: Intraobserver kappa values ranged from 0.366 to 0.664 for observer 1, from 0.311 to 0.447 for observer 2, from 0.597 to 1.000 for observer 3, and from 0.869 to 1 for observer 4. Furthermore, interobserver kappa values among the observers ranged from 0.133 to 0.814 for the first reading and from 0.197 to 0.805 for the second reading. The highest AUC values were found for setting 5 (0.5916) and setting 3 (0.5886), and were not found to be statistically significant(P>.05). Conclusion: Variations in tube voltage and tube current did not affect the detection of recurrent caries under amalgam restorations in primary teeth.

Automatic Control System on Cardiac Output Regulation for the Moving Actuator Type Total Artificial Heart (MOVING-ACTUATOR TYPE 인공심장의 심박출 조절에 대한 자동 제어방법)

  • 김원곤
    • Journal of Chest Surgery
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    • v.28 no.6
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    • pp.542-548
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    • 1995
  • The goal of this study is to develop an effective control system for cardiac output regulation based upon the preload and afterload conditions without any transducers and compliance chambers in the moving actuator type total artificial heart. Motor current waveforms during the actuator movement are used as an input to the automatic control algorithm. While the current waveform analysis is performed, the stroke length and velocity of the actuator are gradually increased up to the maximum pump output level. If the diastolic filling rate of either right or left pump begins to exceed the venous return, atrial collapse will occur. Since the diastolic suction acts as a load to the motor, this critical condition can be detected by analyzing the motor current waveforms. Every time this detection criterion is met, the control algorithm decreases the stroke velocity and length of the actuator step by step just below the critical detection level. Then, they start to increase. In this way the maximum pump output under given venous return can be achieved. Additionally the control algorithm provides some degree of afterload sensitivity. If the aortic pressure is detected to exceed 120 mmHg, the stroke length and velocity decrease in the same way as the response to the preload. Left-right pump output balance is maintained by proper adjustment of the asymmetry of the stroke angle. In the mock circulatory test, this control system worked well and there was a considerable range of stroke volume difference with adjustment of the asymmetry value. Two ovine experiments were performed. It was confirmed that the required cardiac output regulation according to the venous return could be achieved with adequate detection of diastolic function, at least in the in vivo short-term survival cases[2-3 days . We conclude that this control algorithm is a promising method to regulate cardiac output in the moving actuator type total artificial heart.

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Myocardial Perfusion PET (심근관류 PET)

  • Cho, Ihn-Ho;Kong, Eun-Jung
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.3
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    • pp.207-214
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    • 2009
  • Positron emission tomogrpahy (PET) represents the most advanced scintigraphic imaging technology. With the increase in availability of PET, the clinical use of PET has grown in medical fields. This can be employed for cardiovascular research as well as for clinical applications in patients with various cardiovascular disease. PET allows non-invasive functional assessment of myocardial perfusion, substrate metabolism and cardiac innervation and receptors as well as gene expression in vivo. PET is regarded as the gold standard for the detection of myocardial viability, and it is the only method available for the quantitative assessment of myocardial blood flow. This review focuses on the clinical applications of myocardial perfusion PET in coronary artery disease.

Applications of Field-Effect Transistor (FET)-Type Biosensors

  • Park, Jeho;Nguyen, Hoang Hiep;Woubit, Abdela;Kim, Moonil
    • Applied Science and Convergence Technology
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    • v.23 no.2
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    • pp.61-71
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    • 2014
  • A field-effect transistor (FET) is one of the most commonly used semiconductor devices. Recently, increasing interest has been given to FET-based biosensors owing totheir outstanding benefits, which are likely to include a greater signal-to-noise ratio (SNR), fast measurement capabilities, and compact or portable instrumentation. Thus far, a number of FET-based biosensors have been developed to study biomolecular interactions, which are the key drivers of biological responses in in vitro or in vivo systems. In this review, the detection principles and characteristics of FET devices are described. In addition, biological applications of FET-type biosensors and the Debye length limitation are discussed.