• Title/Summary/Keyword: Co-exposure

Search Result 1,004, Processing Time 0.028 seconds

Comparison of Piroxicam Pharmacokinetics and Anti-Inflammatory Effect in Rats after Intra-Articular and Intramuscular Administration

  • Park, Chan Woong;Ma, Kyung Wan;Jang, Sun Woo;Son, Miwon;Kang, Myung Joo
    • Biomolecules & Therapeutics
    • /
    • v.22 no.3
    • /
    • pp.260-266
    • /
    • 2014
  • This study evaluated the pharmacokinetic profile and therapeutic efficacy of piroxicam (PX), a long acting non-steroidal anti-inflammatory drug for the treatment of arthritis, following intra-articular (IA) injection in comparison to the pharmacokinetic profile and therapeutic efficacy of PX after intramuscular (IM) injection. In the pharmacokinetic study in rats, systemic exposure and pharmacokinetic parameters of PX after a single IA dose were compared with systemic exposure and pharmacokinetic parameters of PX after administration of the same dose IM (0.6 mg/kg). The anti-inflammatory and analgesic effects of IA PX were evaluated simultaneously in a monoiodoacetate-induced osteoarthritis rat model. The plasma PX concentration rapidly rose following IA injection, and it was comparable to the plasma PX concentration following IM injection, suggesting the rapid efflux of the drug molecule from the joint cavity. However, in the efficacy study, the IA PX administration significantly reduced the knee swelling by reducing the level of prostaglandin $E_2$ in the joint, compared to that following administration of IA vehicle and after administration of the IM PX dose. In addition, we found that the anti-inflammatory and anti-nociceptive efficacies of IA PX were synergistically increased upon co-treatment with hyaluronic acid (HA), a potent agent for the treatment of osteoarthritis, at the weight ratio of 1:1 or 1:2, and these effects were more pronounced than those following administration of HA or PX alone. In conclusion, this study demonstrated the efficacy of the IA use of PX alone and/or in combination with HA in osteoarthritis.

Effects of Long-term Heat Exposure on Adaptive Mechanism of Blood Acid-base in Buffalo Calves

  • Korde, J.P.;Singh, G.;Varshney, V.P.;Shukla, D.C.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.20 no.5
    • /
    • pp.742-747
    • /
    • 2007
  • In order to investigate the mechanism of adaptation to long-term heat stress, six female buffalo calves of about 7 to 8 months age, were exposed to the cool-comfort environment (THI 65) for 21 days to obtain normal values of blood acid-base. An adaptive response of acid-base regulation was determined to long term (21 days) exposure of buffalo calves to hot-dry (THI 80) and hot-humid (THI 84) conditions. Higher rectal temperature and respiratory rate was recorded under hot-humid exposure compared to hot-dry. Significant reduction in the rectal temperature and respiratory rate on day 21 of hot-dry exposure indicated early thermal adaptation compared to hot-humid. Decreasing rectal temperature and respiratory rate from day 1 to 21 was associated with concurrent decrease in blood pH and pCO2. Increased plasma chloride concentration with low base excess in blood and in extracellular fluid suggested compensatory response to respiratory alkalosis. Reduced fractional excretion of sodium with increased fractional excretion of potassium and urine flow rate indicated renal adaptive response to heat stress.

Heavy Metal Interactions during Accumulation and Elimination of Cadmium and Copper in the Liver of Juvenile Flounder, Paralichthys olivaceus

  • Kim Seong-Gil;Kim Sang-Gyu;Kang Ju-Chan
    • Fisheries and Aquatic Sciences
    • /
    • v.5 no.4
    • /
    • pp.295-301
    • /
    • 2002
  • Experiments were carried out to investigate the effects of metal interaction on the accumulation and elimination of Cd and Cu in the liver of flounder, Paralichthys olivaceus, exposed to sub-chronic Cd (0, 5, 10, 50, 100 ${\mu}g/L$)/Cu $(10 {\mu}g/L)$ mixture. Cd exposure resulted in an increased Cd accumulation in the liver of flounder for exposure periods and concentration, and Cd accumulation increased linearly with exposure time. Cu accumulation profiles were similar to those of Cd. Cd concentration in the liver significantly decreased at the 10th depuration period and elimination rate was $66.20\%,\;86.22\%$ in 50 and $100 {\mu}g/L$at the end of depuration periods, respectively. Although, Cu elimination was similar to Cd elimination phase, Cd elimination rate was higher than that of Cu. Co-relationship of Cd and Cu have a positive correlation coefficient r=0.8620 (P<0.001) and support the strong relationship between Cd and Cu accumulation. As increase with the Cd exposure concentration, there were significant (P<0.001) differences between Cd and Cu accumulation.

The survey of the surface doses of the dental x-ray machines (치과 방사선 촬영기의 표면선량 변화)

  • Lee Jae-Seo;Kang Byung-Cheol;Yoon Suk-Ja
    • Imaging Science in Dentistry
    • /
    • v.35 no.2
    • /
    • pp.87-90
    • /
    • 2005
  • Purpose : The purpose of this study was to investigate variability of doses with same exposure parameters and evaluate radiographic density according to the variability of doses. Materials and methods Twenty-eight MAX-GLS (Shinhung Co, Seoul, Korea), twenty-one D-60-5 (DongSeo Med, Seoul, Korea), and eleven REX-601 (Yoshida Dental MFG, Tokyo, Japan) dental x-ray machines were selected for this study Surface doses were measured under selected combinations of tube voltage, tube current, exposure time, and constant distance 42 cm from the focal spot to the surface of the Multi-O-meter (Unfors Instruments, Billdal, Sweden). Radiographic densities were measured on the films at maximum, minimum and mean surface doses of each brand of x-ray units. Results With MAX-GLS, the maximum surface doses were thirteen to fourteen times as much as the minimum surface doses. With D-60-S, the maximum surface doses were three to eight times as much as the minimum surface doses. With REX-601, the maximum surface doses were six to ten times as much as the minimum surface doses. The differences in radiographic densities among maximum, mean, and minimum doses were significant (p<0.01). Conclusion : The surface exposure doses of each x-ray machine at the same exposure parameters were different within the same manufacturer's machines.

  • PDF

Characterization of Durability of PC panel by Accelerating Test in Deterioration Chamber and Long-Term Field Exposure Test (촉진열화 및 장기폭로시험에 의한 고성능 PC패널의 내구성능 및 열화특성)

  • Ma, Sang-Joon;Jang, Pil-Sung;Choi, Jae-Suk;Ju, Jung-Min
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.1549-1554
    • /
    • 2008
  • In this paper, The evaluation of durability of the PC Panel lining for tunnel structure was examined through the rapid test by carbonation and freezing and thawing. Also for the purpose of improvement of durability. Namely, the durable characteristics of PC Panel lining by carbonation and freezing and thawing, was evaluated by rapid test and long-term field exposure test and main influence factors were derived. As a result of test, Correlation of accelerating test in deterioration chamber and long-term field exposure test, it will be expected that the proposed correlation well to the prediction of life expectancy of structure and is contributed greatly in the future.

  • PDF

Example of Air Exposure Assessment for Fire Extinguishing Agent Residues (소화약제 잔류물질에 대한 공기 중 노출평가 사례)

  • Daesung Lim
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.34 no.1
    • /
    • pp.14-17
    • /
    • 2024
  • Objectives: This is a case of air exposure assessment conducted after researchers complained of headaches and odor due to residual substances from fire extinguishing agents spread throughout the laboratory due to a malfunction of the fire extinguishing facility. Methods: A component analysis was conducted on the residual substances of a fire extinguishing agent spread in a laboratory using Py-GC-MS (pyrolysis gas chromatography mass spectrometry) at the research institute's own central equipment research center. As a result of the component analysis, several types of substances were detected. Among these, five types of substances subject to work environment measurement in the aromatic hydrocarbon series, which can affect headaches and odor, were selected as substances subject to exposure assessment in the air, and the measurement and analysis methods of the target substances were conducted in accordance with the KOSHA Guide for each substance. Conclusions: The measurement results showed that all 5 types of substances were not detected at locations A, B, and C. This is believed to be the result of the residual substances in the fire extinguishing agent being measured when approximately two months had elapsed after being exposed to the test bench, and the substances already exposed had volatilized and disappeared. In this survey, it is believed that the measurement process is more important than the measurement results.

Evaluation of Tensile Property of Austenitic Alloys Exposed to High-Temperature S-CO2 Environment (고온 S-CO2 환경에 노출된 오스테나이트계 합금의 인장특성 평가)

  • Kim, Hyunmyung;Lee, Ho Jung;Jang, Changheui
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.38 no.12
    • /
    • pp.1415-1420
    • /
    • 2014
  • Super-critical $CO_2$ ($S-CO_2$) Brayton cycle has been considered to replace the current steam Rankine cycle in Sodium-cooled Fast Reactor (SFR) in order to improve the inherent safety and thermal efficiency. Several austenitic alloys are considered as the structural materials for high temperature $S-CO_2$ environment.. Microstructural change after long-term exposure to high temperature $S-CO_2$ environment could affect to the mechanical properties. In this study, candidate materials (austenitic stainless steels and Alloy 800HT) were exposed to $S-CO_2$ to assess oxidation resistance and the change in tensile properties. Loss of ductility was observed for some austenitic stainless steels even after 250 h exposure. The contribution of $S-CO_2$ environment on such changes was analyzed based on the characterization of the surface oxide and carburization of the materials in which 316H and 800H showed different oxidation behaviors.

Research of the TFT-LCD Photosensitive Resist Thickness

  • Zhang, Mi;Xue, Jian She;Wang, Wei;Park, Chun-Bae;Koh, Jai-Wan;Zhang, Zhi-Min
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.1269-1271
    • /
    • 2008
  • We find some array mura are caused by S/D bridge or channel open in 4 mask process. The gray tone PR thickness non-uniformity is the main reason of these defects. By the adjustment of exposure and dry etch parameters, S/D bridge and channel open ratio drops by 10.87%.

  • PDF

Control of Enzymatic Degradability of Microbial Polyester by Surface Modification (표면 개질을 통한 미생물합성 폴리에스테르의 효소분해속도 조절)

  • 이원기
    • Journal of Environmental Science International
    • /
    • v.11 no.12
    • /
    • pp.1315-1320
    • /
    • 2002
  • Since the enzymatic degradation of microbial poly[(R)-3-hydroxybutyrate-co-3-hydroxyvalerate] (P(3HB-co-3HV)) initially occurs by a surface erosion process, a degradation behavior could be controlled by the change of surface property. In order to control the rate of enzymatic degradation, plasma gas discharge and blending techniques were used to modify the surface of microbial P(3HB-co-3HV). The surface hydrophobic property of P(3HB-co-3HV) film was introduced by CF$_3$H plasma exposure. Also, the addition of small amount of polystyrene as a non-degradable polymer with lower surface energy to P(3HB-co-3HV) has been studied. The enzymatic degradation was carried out at 37 $^{\circ}C$ in 0.1 M potassium phosphate buffer (pH 7.4) in the presence of an extracellular PHB depolymerase purified from Alcaligenes facalis T1. Both results showed the significant retardation of enzymatic erosion due to the hydrophobicity and the enzyme inactivity of the fluorinated- and PS-enriched surface layers.