• Title/Summary/Keyword: USP

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Synthesis and Characterization of Al2O3/ZrO2, Al2O3/TiO2 and Al2O3/ZrO2/TiO2 Ceramic Composite Particles Prepared by Ultrasonic Spray Pyrolysis

  • Shim, In-Soo;Lee, Chang-Seop
    • Bulletin of the Korean Chemical Society
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    • v.23 no.8
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    • pp.1127-1134
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    • 2002
  • Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutio ns of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle syntheses have been proposed.

Dissoultion and Rectal Absorption of Acetaminophen from Suppositories (아세트아미노펜 좌제의 용출과 직장흡수)

  • 한정선;심창구;김신근
    • YAKHAK HOEJI
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    • v.31 no.5
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    • pp.286-295
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    • 1987
  • The relationship between in vitro release and in vivo bioavailability of acetaminophen from suppositories was investigated. Effect of glycyrrhizin on the drug release and rectal absorption in rats was also examined. Suppositories containing 25mg of acetaminophen were prepared with Wecobee FS (fatty base) or PEG (water-soluble base) bases. The release from the suppositories were determined with USP rotating basket dissolution apparatus and with the suppository release tester. The temperature of the dissolution medium was very critical for the dissolution of acetaminophen from Wecobee FS suppositories. The bioavailability of acetaminophen was calculated from the plasma concentration-time curve after rectal administration of the suppositories to the rats. There were no significant differences in AUC following rectal administration of Wecobee FS and PEG suppositories, but the release and absorption from the Wecobee FS suppositories were faster than those from PEG suppositories. The dissolution rate obtained by the suppository release tester was better correlated with in vivo absorption rate constant than that by the USP dissolution apparatus. It suggests that the partitioning between rectal fluid and suppository base is the rate-limiting step in the rectal absorption of acetaminophen from suppositories. Glycyrrhizin was found not to affect in vitro dissolution and rectal absorption of acetaminophen.

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Development of a Food-Grade Integration Vector for Heterologous Gene Expression and Protein Secretion in Lactococcus lactis

  • Jeong, Do-Won;Lee, Jong-Hoon;Kim, Kyoung-Heon;Lee, Hyong-Joo
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1799-1808
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    • 2006
  • A food-grade integration vector based on site-specific recombination was constructed. The 5.7-kb vector, pIMA20, contained an integrase gene and a phage attachment site originating from bacteriophage A2, with the ${\alpha}$-galactosidase gene from Lactobacillus plantarum KCTC 3104 as a selection marker. pIMA20 was also equipped with a controllable promoter of nisA ($P_{nisA}$) and a signal peptide-encoding sequence of usp45 ($SP_{usp45}$) for the production and secretion of foreign proteins. pIMA20 and its derivatives mediated site-specific integration into the attB-like site on the Lactococcus lactis NZ9800 chromosome. The vector-integrated recombinant lactococci were easily detected by the appearance of blue colonies on a medium containing $X-{\alpha}-gal$ and also by their ability to grow on a medium containing melibiose as the sole carbon source. Recombinant lactococci maintained these traits in the absence of selection pressure during 100 generations. The ${\alpha}-amylase$ gene from Bacillus licheniformis, lacking a signal peptide-encoding. sequence, was inserted downstream of $P_{nisA}\;and\;SP_{usp45}$ in pIMA20, and the plasmid was integrated into the L. lactis chromosome. ${\alpha}-Amylase$ was successfully produced and secreted by the recombinant L. lactis, controlled by the addition and concentration of nisin.

Efficacy of reciprocating instruments and final irrigant activation protocols on retreatment of mesiobuccal roots of maxillary molars: a micro-CT analysis

  • Lilian Tietz;Renan Diego Furlan;Ricardo Abreu da Rosa;Marco Antonio Hungaro Duarte;Murilo Priori Alcalde;Rodrigo Ricci Vivan;Theodoro Weissheimer;Marcus Vinicius Reis So
    • Restorative Dentistry and Endodontics
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    • v.47 no.1
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    • pp.13.1-13.13
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    • 2022
  • Objectives: This study evaluated the efficacy of 3 reciprocating systems and the effects of 2 instruments for irrigant activation on filling material removal. Materials and Methods: Forty mesiobuccal roots of maxillary molars were prepared up to size 25.06 and obturated. Micro-computed tomography (micro-CT) examination #1 was performed. Teeth were then divided into 4 groups (n = 10), according to the retreatment protocol: (1) manual, (2) Reciproc Blue, (3) WaveOne Gold, and (4) X1 Blue. Micro-CT examinations #2 and #3 were performed after filling removal and repreparation, respectively. Next, all teeth were divided into 2 new groups (n = 20) according to the irrigant activation protocol: XP Clean (XP Clean size 25.02) and Flatsonic (Flatsonic ultrasonic tip). Micro-CT examination #4 was performed after irrigant activation. Statistical analysis was performed with a significance level set at 5%. Results: WaveOne Gold removed a significantly greater amount of filling material than the manual group (p < 0.05). The time to reach the WL was similar for all reciprocating systems (p > 0.05). X1 Blue was faster than the manual group (p < 0.05). Only manual group improved the filling material removal after the repreparation stage (p < 0.05). Both activation protocols significantly improved the filling material removal (p < 0.05), without differences between them (p > 0.05). Conclusions: None of the tested instruments completely removed the filling material. X1 Blue size 25.06 reached the working length in the shortest time. XP Clean and Flatsonic improved the filling material removal.

Quality Control of Residual Solvents in $[^{18}F]$FDG Preparations by Gas Chromatography (기체 크로마토그래피를 이용한 $[^{18}F]$FDG 주사액 중의 잔류 용매의 정도관리)

  • Lee, Hak-Jeong;Jeong, Jae-Min;Lee, Yun-Sang;Kim, Hyung-Woo;Chang, Young-Soo;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.6
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    • pp.566-569
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    • 2007
  • Purpose: Analysis of volatile organic solvents in 2-deoxy-2-$[^{18}F]$ fluoro-D-glucose ($[^{18}F]$FDG) preparations was performed by gas chromatography (GC), in accordance with USP. Materials and Methods: Analyses were carried out on a Hewlett-Packard 6890 gas chromatography equipped with an FID. Results: We determined the amounts of ethanol and acetonitrile on every batch of our routine $[^{18}F]$FDG preparations, ranging between 5000 ppm and 100 ppm. In our routine preparation of $[^{18}F]$FDG, the amount of acetonitrile and ethanol in the final product were well below the maximum allowable limit described in the USP. Conclusion: Our $[^{18}F]$FDG preparations were in accordance with the suggested USP maximum allowable levels of the quality control analysis of volatile organic compounds.

COINCIDENCE OF MAPS BETWEEN SURFACES

  • Goncalves, Daciberg L.
    • Journal of the Korean Mathematical Society
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    • v.36 no.2
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    • pp.243-256
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    • 1999
  • We will consider f,g : S1longrightarrowS2 a pair of maps between two orientable compact surfaces. The purpose of this paper is to decide when the pair can be deformed to a pair (f', g') such that

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Standardization of Pancreatin (판크레아틴의 규격 표준화 연구)

  • Shin, Ji-Eun;Yoon, Hae-Kyung;Kim, Dong-Hyun
    • Journal of Pharmaceutical Investigation
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    • v.33 no.4
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    • pp.273-279
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    • 2003
  • Pancreatin is a enzyme mixture breaking down carbohydrates, proteins and lipids. Most pancreatin used in Korea is imported from foreign countries. However, guideline of each country for pancreatin produced from each country is different. Therefore, guideline for pancreatin imported from several countries, such as Europe, Japan and America, it is standardized to control its quality. Assay of enzyme activity for pancreatin in KP is similar to tat in JP, but it is significantly different from those in FP ad in USP. We measured pancreatin digestive activities of 17 commercial products. Activity assay of digestive enzymes, starch- and lipid-digestive enzymes, for pancreatin by KP method (including JP) was difficult compared to those by FIP ad USP methods. Particularly, activity assays of starch- and lipid-digestive enzymes by KP method were mistakable, ad varied in diluted samples than those by FIP. However, activity assay of protein-digestive enzyme by KP method was similar to that by FIP. Starch-digestive enzyme activities of 17 commercial pancreatins by KP method were lower 0.079-fold compared to those by FIP method. Their protein-digestive enzyme activities by KP method were higher 75.7-fold than those by FIP method. Their lipid-digestive enzyme activities by KP method were lower 0.234-fold compared to those by FIP method.