• Mass Spectrometry Letters
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• v.10 no.1
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• pp.38-42
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• 2019

Damaurone D belongs to the genus Rosa and is a traditional medicinal product used for the treatment of depression, inflammation, and infectious diseases. The purpose of this study was to develop a simple liquid chromatography-tandem mass spectrometry method for the detection of damaurone D in rat plasma and to demonstrate its application in pharmacokinetic studies. Damaurone D and berberine (internal standard) were extracted with acetonitrile using a protein precipitation method. Mass transition was monitored in multiple reaction monitoring mode at m/z $323.2{\rightarrow}267.0$ for damaurone D and m/z $336.1{\rightarrow}320.0$ for berberine in positive ion mode. Analytical validation was conducted by evaluating the specificity, linearity, accuracy, precision, matrix effect, extraction recovery, and stability. The calibration curves were linear over 2-1000 ng/mL. The intra- and inter-day precision and accuracy of quality control samples were 4.79-13.33% and 86.23-102.75%, respectively. The matrix effect and extraction recovery were 96.11-98.47% and 96.11-102.25%, respectively. In the pharmacokinetic study after intravenous administration of damaurone D at a dose of 3 mg/kg in rats, the area under the curve and clearance of damaurone D in rat plasma were $16750.26{\pm}2676.10min{\cdot}ng/mL$ and $182.44{\pm}31.36mL/min/kg$, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.14-22
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• 2019

Objective: The aim of the study was to find a possible association between the ${\beta}-$ and ${\kappa}-casein$ and ${\beta}-lactoglobulin$ genotypes and important milk physiochemical and technological characteristics such as acidity, alcohol stability, the contents of some minerals and the parameters of acid fermentation ability (FEA) in Czech Fleckvieh Cattle. Methods: Milk and blood samples were collected from 338 primiparous Czech Fleckvieh cows at the same stage of lactation. The genotypes of individual cows for ${\kappa}-casein$ (alleles A, B, and E) and ${\beta}-lactoglobulin$ (alleles A and B) were ascertained by polymerase chain reaction-restriction fragment length polymorphism, while their ${\beta}-casein$ (alleles $A^1$, $A^2$, $A^3$, and B) genotype was determined using melting curve genotyping analysis. The data collected were i) milk traits including active acidity (pH), titratable acidity (TA), alcohol stability (AS); calcium (Ca), phosphorus (P), sodium (Na), magnesium (Mg), and potassium (K) contents; and ii) yoghurt traits including active acidity (Y-pH), titratable acidity (Y-TA), and the counts of both Lactobacilli and Streptococci in 1 mL of yoghurt. A linear model was assumed with fixed effects of herd, year, and season of calving, an effect of the age of the cow at first calving and effects of the casein and lactoglobulin genotypes of ${\beta}-CN$ (${\beta}-casein$, CSN2), ${\kappa}-CN$ (${\kappa}-casein$, CSN3), and ${\beta}-LG$ (${\beta}-lactoglobulin$, LGB), or the three-way interaction between those genes. Results: The genetic polymorphisms were related to the milk TA, AS, content of P and Ca, Y-pH and Lactobacilli number in the fresh yoghurt. The CSN3 genotype was significantly associated with milk AS (p<0.05). The effect of the composite CSN2-CSN3-LGB genotype on the investigated traits mostly reflected the effects of the individual genes. It significantly influenced TA (p<0.01), Y-pH (p<0.05) and the log of the Lactobacilli count (p<0.05). Conclusion: Our findings indicate that the yoghurt fermentation test together with milk proteins genotyping could contribute to milk quality control and highlight new perspectives in dairy cattle selection.

• Journal of Pharmaceutical Investigation
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• v.29 no.2
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• pp.87-92
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• 1999

Drug delivery to the brain may be achieved by producing chimeric peptide, attaching the drug to protein 'vectors' which are transported into the brain from the blood by a receptor-mediated transcytosis through the blood-brain barrier (BBB). Since the BBB expresses high concentrations of transferrin receptor, and it was reported that anti-transferrin receptor mouse monoclonal antibody (OX26) undergoes transcytosis through the BBB, it is logical to assume that a drug delivery system via transferrin receptor-mediated transcytosis is a promising strategy. In the present study, therefore, we tested feasibility of several OX26 based vectors for the brain delivery of a model drug. Avidin-based delivery vectors such as OX26-streptavidin (OX26-SA), OX26-neutralite avidin (OX26-NLA) were chemically synthesized vectors and OX26 immunoglobulin G 3 type $C_{H}3$ fusion avidin $(OX26\;IgG3C_H3-AV)$ was genetically engineered. To improve the efficiency of producing chimeric peptide, we used avidin-biotin technology. Pharmacokinetics of $[^3H]biotin$ bound to OX26-SA, OX26-NLA and $OX26\;IgG3C_H3-AV$ was determined by intravenous injection technique, and their stabilities in plasma were analyzed using HPLC. The brain delivery of $[^3H]biotin$ bound to OX26-SA, OX26-NLA and OX26\;$IgG3C_{H}3-AV$ (expressed as %ID/g brain) was $0.22{\pm}0.01$, $0.18{\pm}0.01$ and $0.25{\pm}0.09$, respectively. The areas under the plasma concentration versus time curve (AUC) for OX26-SA, OX26-NLA, $OX26\;IgG3C_H3-AV$ from time zero to 60 min were $209{\pm}10$, $195{\pm}9$, $134{\pm}29\;%ID\;min/ml$ respectively and their total clearances $(CL_{tot})$ were $1.00{\pm}0.09$, $1.08{\pm}0.07$ and $1.54{\pm}0.29\;ml/min/kg$, espectively. These results showed that these vectors possess preferable pharmaceutical (e.g., resonable stability) and pharmacokinetics (e.g., significant brain uptake and enhanced AUC) for brain delivery. Therefore, these vectors may be broadly useful in the brain delivery of drugs that are not transported into the brain to a significant extent.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.2
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• pp.139-148
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• 2012

Purpose : Since standard solution is the one that knows its exact concentration, the curve of the dissolution has been determined according to the amount of the solution, compared to the amount of the unknown sample. Therefore, the antigen that makes up standard materials should be made in a pure form. The configuration of the standard substance solution in the kit we use is a freeze-dried material, or made and comes as a liquid. Lyophilized reference material is used after dissolving in usually D.W. (Distilled Water), and if the antigen to use is too sensitive, reagents should be freeze-dried. Furthermore, when freeze-dried reference has to be frozen again after being dissolved, it should be kept under $-20^{\circ}C$ until the expiration date according to the reports. Since it is not expressed in the experiment if it is safe or stable to reuse the solution which was dissolved a few times, thus, this time it is tested and evaluated that the changes of the standard solution by freezing and melting several times, and its results and the effectiveness of it were compared to the solution which was kept in a fridge. Materials and Methods : Among Vitro diagnostic kits on the market made by radioimmunoassay, parathyroid hormone (PTH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH) are made of freeze-dried standard solution and all composed of the same Lot.NO. These hormones melted in D.W. and were separated into three groups. In the first group, melting and freezing were repeated, and in the second group, The solution only for one time use was put into a test tube after melting and freeze it. The third group was kept in the refrigerator. This experiment has been conducted from January to February in 2012. January to 2012. PH test was employed because ph is prone to changing depending on the change of protein. Each group of the standard solution, cpm (counter per minute), and the patient relative concentration values were compared by date, and Through the correlation coefficient and Paired t-test, the significant level of each group was analyzed. Results : ACTH, PTH, LH pH values were too subtle denaturation rather than numerical changes in the protein. In addition, when the standard solution of ACTH, PTH, LH was refrigerated, after 3 days and 7 days, there was a significant difference observed between the solution being kept in a refrigerator and a freezer within a significance level. Conclusion : Standard solution should be kept in a freezer, and being kept in a fridge, it is recommended to use the solution as soon as possible.