1.In Vitro Bioassay of Endotoxin Using Fluorescein as a pH Indicator in a Macrophage Cell Culture System.
Dong Hee LEE ; Hak Joon SUNG ; Dong Wook HAN ; Min Sub LEE ; Gyu Ha RYU ; Maki AIHARA ; Kosuke TAKATORI ; Jong Chul PARK
Yonsei Medical Journal 2005;46(2):268-274
Based on the biological activity of endotoxin, we propose a possible new method for detecting endotoxin using a pH- indication system of macrophage culture media. After RAW 264.7 macrophage cells were treated with lipopolysaccharide (LPS), the addition of fluorescein to the LPS-treated media reproductively reduced its absorption and emission spectra (it was a dose-dependent reduction). The advantages of this LPS- detection method were compared with the Limulus Amebocyte Lysate (LAL) test by using purified bacterial LPS (Salmonella minnessota, Escherichia coli, and Pseudomonas aeruginosa). Additionally, the absorption and fluorescence intensity of fluorescein, following treatment of RAW 264.7 cells with a high concentration of Staphylococcus aureus (Gram-positive, lysed bacteria), could not generally be detected by the LAL test, but they were found to be reduced, in a dose-response relationship, with this new system. The macrophage culture system-method might be a good supplement to the LAL assay for detection of LPS, Gram-negative and Gram-positive bacteria.
Animals
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Biological Assay/*methods/standards
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Cells, Cultured
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Comparative Study
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*Contrast Media
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Culture Media/chemistry
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Endotoxins/*analysis
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*Fluorescein
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Hydrogen-Ion Concentration
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Limulus Test
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Lipopolysaccharides/analysis
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Macrophages/*chemistry
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Mice
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Research Support, Non-U.S. Gov't
2.Taxonomic characterization and isolation of antitrypanosomal compound from Streptomyces sp. FACC-A032 isolated from Malaysian forest soil
Lili Sahira Husin1 ; Getha Krishnasamy ; Muhd Syamil Azahar ; Hema Thopla Govender ; Norhayati Ismail ; Muhd Haffiz Jauri ; Siti Syarifah Mohd Mutalip ; Mohd Ilham Adenan
Malaysian Journal of Microbiology 2015;11(2):128-136
Aims: The present study is aimed at taxonomic characterization and isolation of active compound MS01 from
Streptomyces sp. FACC-A032 which exhibited strong antitrypanosomal activity (IC50 0.02 μg/mL).
Methodology and results: Isolate FACC-A032 was characterized based on its cultural, morphological, physiological
and genomic properties. Isolate FACC-A032 was tentatively identified as Streptomyces sp. Biochemical analysis of
diaminopimelic acid (DAP) isomer of whole-cell hydrolysates further confirmed the isolate FACC-A032 that contained
LL-DAP isomer as species belonging to the genus Streptomyces. The inoculum for submerged cultures of isolate FACCA032
was prepared from cultures on ISP2 agar. After eight days of growth at 28 2 °C and 200 rpm in fermentation
medium M3, fermentation broth was extracted with butanol and the crude extracts (solvent layer) were separated and
dried in vacuo. Further studies were carried out to isolate the active compound from the culture extracts of isolate FACCA032.
Using bioassay-guided isolation, crude extract was partitioned based on different polarity. After which, the
resulting elutes were tested for antitrypanosomal activity. The active fraction was analyzed with HPLC-DAD analysis.
Based on the analysis, major peak in the active fraction was collected using HPLC preparative. Active compound MS01
was isolated and structure elucidated using NMR spectroscopy.
Conclusion, significance and impact of study: Bioassay-guided isolation techniques used in this study had
discovered an active antitrypanosomal compound, staurosporine, from Streptomyces sp. FACC-A032. This is the first
discovery of staurosporine, a protein kinase inhibitor, from Malaysian soil actinobacteria Streptomyces sp. Therefore, the
study demonstrated the potential of Malaysian soil actinobacteria as antitrypanosomal therapeutic agent.
Biological Assay
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Actinobacteria
3.Concentration of the tumor maker CA72-4 in the normal people (Quantitative analysis by the Immunoradioactive method IRMA).
Journal of Practical Medicine 2002;435(11):11-13
Subjects: Normal people without the benign or malignant tumor; standard sample of CA72-4 with concentrations: 0,3; 25; 50 100 u/ml. The results have shown that the standard chart has relatively same as theory; the change factor CV had value within allowed limit in the range of low concentration of CA 72-4 was 4,05+/- 3,06U/ml. The medium value was 4,92 u/ml. The normal range is from 0 to 9 u/ml. There is insignificant different between women and men.
Neoplasms
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Immunoradiometric Assay
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Tumor Markers, Biological
4.Scientific rationale and applicability of dose-reponse models for environmental carcinogens.
Dongchun SHIN ; Yong CHUNG ; Jongman KIM ; Seongim G LEE ; Mansik HWANG
Korean Journal of Preventive Medicine 1996;29(1):27-42
This study described methods to predict human health risk associated with exposure to environmental carciongens using animal bioassay data. Also, biological assumption for various dose-response models were reviewed. To illustrate the process of risk estimate using relevant dose-response models such as Log-normal, Mantel-Bryan, Weibull and Multistage model, we used four animal carcinogenesis bioassy data of chloroform and chloroform concentrations of tap water measured in large cities of korea from 1987 to 1995. As a result, in the case of using average concentration in exposure data and 95 % upper boud unit risk of Multistage model, excess cancer risk(RISK I) was about 1.9 x 10-6, in the case of using probability distribution of cumulative exposure data and unit risks, those risks(RISK II) which were simulated by Monte-Carlo analysis were about 2.4 x 10(-6) and 7.9 x 10(-5) at 50 and 95 percentile, respectively. Therefore risk estimated by Monte-Carlo analysis using probability distribution of input variables may be more conservative.
Animals
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Biological Assay
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Carcinogenesis
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Carcinogens, Environmental*
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Chloroform
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Humans
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Korea
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Water
5.Erythropoietin Bioassay in 7 Cases of Hydronephrosis and Renal Cell Carcinoma.
Korean Journal of Urology 1972;13(2):101-105
It has been well established that the kidney is the main organ producing erythropoietin (E.S.F.). Erythropoietin activity was reported to be increased in cases of renal tumor. cyst, polycystic disease and hydronephrosis. To study erythropoietic activity in hydronephrosis and renal cell carcinoma, erythropoietin bioassay by DeGowin method were performed in 7cases of hydronephrosis and renal cell carcinoma. Erythropoietin activity is significantly increased in renal cell carcinoma but not significantly increasedin hydronephrosis.
Biological Assay*
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Carcinoma, Renal Cell*
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Erythropoietin*
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Hydronephrosis*
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Kidney
6.Androgen abuse in sports.
David J HANDELSMAN ; Alison HEATHER
Asian Journal of Andrology 2008;10(3):403-415
Androgens remain the most effective and widely abused ergogenic drugs in sport. Although androgen doping has been prohibited for over 3 decades with a ban enforced by mass spectrometric (MS)-based urine testing for synthetic and exogenous natural androgens, attempts continue to develop increasingly complex schemes to circumvent the ban. A prominent recent approach has been the development of designer androgens. Such never-marketed androgens evade detection because mass spectrometry relies on identifying characteristic chemical signatures requiring prior knowledge of chemical structure. Although once known, designer androgens are readily detected and added to the Prohibited List. However, until their structures are elucidated, designer androgens can circumvent the ban on androgen doping. To combat this, in vitro androgen bioassays offer powerful new possibilities for the generic detection of unidentified bioactive androgens, regardless of their chemical structure. Another approach to circumvent the ban on androgen doping has been the development of indirect androgen doping, the use of exogenous drugs to produce a sustained increase in endogenous testosterone (T) production. Apart from estrogen blockers, however, such neuroendocrine active drugs mostly provide only transient increases in blood T. Finally the ban on androgen doping must allow provision for rare athletes with incidental, proven androgen deficiency who require T replacement therapy. The Therapeutic Use Exemption mechanism makes provision for such necessary medical treatment, subject to rigorous criteria for demonstrating a genuine ongoing need for T and monitoring of T dosage. Effective deterrence of sports doping requires novel, increasingly sophisticated detection options calibrated to defeat these challenges, without which fairness in sport is tarnished and the social and health idealization of sporting champions devalued.
Androgens
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administration & dosage
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Biological Assay
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Designer Drugs
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Doping in Sports
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Humans
7.Effects of aqueous and pelletized admixute of Piper nigrum L on the oviposition behavior of Aedes aegypti mosquitoes and its larvicidal-ovicidal activity.
Briones Annabelle V ; Garbo Alicia G ; Casa Edmar P ; Bion Hermelina H ; Almanzor Nuna E ; Bernardo Severino T
Acta Medica Philippina 2012;46(3):55-58
OBJECTIVE: The aqueous and pelletized admixture of Piper nigrum L. was evaluated for its oviposition response and larvicidal activity against Aedes aegypti mosquitoes.
METHODS: The aqueous and pelletized extract of Piper nigrum L. was prepared and first tested in the laboratory. Efficiency is evaluated using the mosquito-chamber test. A small-scale field test was also done to determine the oviposition response of the pepper extract to ovicidal-larvicidal (OL) traps. Larvicidal bioassay following the WHO standard protocols with slight modification at different concentrations was performed.
RESULTS: Results of the mosquito chamber test in the laboratory showed that the aqueous solution exhibited an increasing rate of oviposition attraction of female Aedes aegypti to increasing rate of concentration with an average of 70% attraction at 1000 ppm as compared to 30% attraction to OL traps with water alone. The aqueous pepper-based solution and pelletized pepper solution at 1000 and 2000 ppm are considered attractants to Aedes mosquitoes. Both solutions have oviposition activity index (OAI) of > +0.3. It was also field tested on the 10 buildings within the Department of Science and Technology (DOST) compound. Results showed an oviposition ratio two times better in both the 1000 ppm concentration of the aqueous pepper-based solution and pelletized pepper solution as compared to the control. The positive ovitrap index was in the range of 78%-84% for both the aqueous pepper-based and pelletized pepper against water which is 70.0%. Larvicidal activity of the aqueous pepper-based solution against 3rd larval instars of Aedes aegypti at increasing dosages from 75mg/1 to 600 mg/I had an LCso of 127 mg/I and 395 mg/I for LC90 The LCso for the solution with pelletized pepper at the same dosing concentration is 117 mg/I with LC90 of 285 mg/1. The results also showed that these can be used to control larval instars of the Aedes aegypti mosquitoes.
CONCLUSION: The overall results indicate that the aqueous and pelletized extracts of Piper nigrum L. are effective in attracting the Aedes aegypti mosquitoes for oviposition and exhibit a larvicidal activity.
Animal ; Aedes ; Piper Nigrum ; Larva ; Oviposition ; Water ; Biological Assay
8.Selection of Lecanicillium Strain with High Virulence against Developmental Stages of Bemisia tabaci.
Mycobiology 2010;38(3):210-214
Selection of fungal strains with high virulence against the developmental stages of Bemisia tabaci was performed using internal transcribed spacer regions. The growth rate of hyphae was measured and bioassay of each developmental stage of B. tabaci was conducted for seven days. All of the fungal strains tested were identified as Lecanicillium spp., with strain 4078 showing the fastest mycelium growth rate (colony diameter, 16.3 +/- 0.9 mm) among the strains. Compared to strain 4075, which showed the slowest growth rate, the growth rate of strain 4078 was increased almost 2-fold after seven days. Strains 4078 and Btab01 were most virulent against the egg and larva stages, respectively. The virulence of fungal strains against the adult stage was high, except for strains 41185 and 3387. Based on the growth rate of mycelium and level of virulence, strains 4078 and Btab01 were selected as the best fungal strains for application to B. tabaci, regardless of developmental stage.
Adult
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Biological Assay
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Humans
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Hyphae
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Larva
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Mycelium
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Ovum
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Sprains and Strains
9.PCL/β-TCP Composite Scaffolds Exhibit Positive Osteogenic Differentiation with Mechanical Stimulation.
So Hee PARK ; Su A PARK ; Yun Gyeong KANG ; Ji Won SHIN ; Young Shik PARK ; Seo Rin GU ; Yan Ru WU ; Jie WEI ; Jung Woog SHIN
Tissue Engineering and Regenerative Medicine 2017;14(4):349-358
We investigated the use of Polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP) composites with applied mechanical stimulation as scaffold for bone tissue engineering. PCL-based three-dimensional (3D) structures were fabricated in a solvent-free process using a 3D-printing technique. The mass fraction of β-TCP was varied in the range 0–30%, and the structure and compressive modulus of the specimens was characterized. The shape and interconnectivity of the pores was found to be satisfactory, and the compressive modulus of the specimens was comparable with that of human trabecular bone. Human mesenchymal stem cells were seeded on the composites, and various biological evaluations were performed over 9 days. With a mass fraction of β-TCP of 30%, differentiation began earlier; however, the cell proliferation rate was lower. Through the use of mechanical stimulation, however, the proliferation rate recovered, and was comparable with that of the other groups. This stimulation effect was also observed in ECM generation and other biological assays. With mechanical stimulation, expression of osteogenic markers was lower on samples with a β-TCP content of 10 wt% than without β-TCP; however, with mechanical stimulation, the sample with a β-TCP content of 30 wt% exhibited significantly greater expression of those markers than the other samples. We found that mechanical stimulation and the addition of β-TCP interacted closely, and that a mass fraction of β-TCP of 30% was particularly useful as a bone tissue scaffold when accompanied by mechanical stimulation.
Biological Assay
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Bone and Bones
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Cell Proliferation
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Humans
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Mesenchymal Stromal Cells
10.Interim In vitro Dose-Response Curve for the Dicentric Biodosimeter Assay from a Philippine Radiotherapy Facility using a Linear Accelerator
Antonio Carlo D. De Guzman ; Carmencita D. Padilla ; Henri Cartier S. Co ; Elrick T. Inocencio ; Edsel Allan G. Salonga
Acta Medica Philippina 2021;55(1):117-125
Background. Accidental radiation exposure can occur anytime. Biodosimeters help in quantifying the absorbed dose of individuals who are not equipped with personal dosimeters during radiation exposure. The dicentric assay can quantify radiation damage by correlating radiation dose exposure with the frequency of dicentric chromosomes in the peripheral lymphocytes extracted from exposed individuals.
Objective. The study aims to present the interim results of the reference dose-response curve for a Philippine radiotherapy facility constructed using a 6MV linear accelerator (ClinacX, Varian).
Methods. Samples of peripheral blood from healthy volunteers were irradiated in a customized water phantom of doses 0.10 to 5.0 Gray using a linear accelerator. The irradiated samples were cultured and analyzed following the International Atomic Energy Agency Cytogenetic Dosimetry Protocol (2011) with modifications. Linear-quadratic model curve fitting and further statistical analysis were done using CABAS (Chromosome Aberration Calculation Software Version 2.0) and Dose Estimate (Version 5.2). Interim results of the samples were used to generate these curves.
Results. The dose-response curve generated from the preliminary results were comparable to published dose response curves from international cytogenetic laboratories.
Conclusion. The generated dose-response calibration curve will be useful for medical triage of the public and radiologic staff accidentally exposed to radiation during medical procedures or in the event of nuclear accidents.
Cytogenetics
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Biological Assay
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Chromosome Disorders
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Cytogenetic Analysis
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Radiation