Biodegradation of metolachlor in a soil perfusion experiment

1988 ◽  
Vol 5 (4) ◽  
Author(s):  
S.-Y. Liu ◽  
R. Zhang ◽  
J.-M. Bollag
Keyword(s):  
Perfusion Experiment

VANILLINSÄURE ALS ENDPRODUKT DES STOFFWECHSELS VON ADRENALIN UND NORADRENALIN. II.

1963 ◽  
Vol 44 (1) ◽  
pp. 101-106 ◽  
Author(s):  
Wilhelm Dirscherl ◽  
Helmut Thomas
Keyword(s):  
Rat Liver ◽  
Paper Chromatography ◽  
Column Chromatography ◽  
Vanillic Acid ◽  
Hippuric Acid ◽  
Single Spot ◽  
Solvent Systems ◽  
Perfusion Experiment ◽  
Kinetics Of

ABSTRACT Perfusion of rat liver with vanillic acid yielded only one metabolite. In paper chromatography with three different solvent systems, the substance showed the same RF-values as vanillyolglycine (3-methoxy-4-hydroxyhippuric acid) and in mixed chromatograms there was only one single spot. After separation by column chromatography, the UV- and IRspectra of the reaction product were identical with those of 3-methoxy4-hydroxy-hippuric acid. During the perfusion experiment, the kinetics of the conjugation were investigated.

EVALUATION OF MECHANICAL SYSTEMS USED IN PERFUSION

1972 ◽  
Vol 68 (2_Supplb) ◽  
pp. S44-S73 ◽  
Author(s):  
Eugene F. Bernstein
Keyword(s):  
Mechanical Systems ◽  
Organ Perfusion ◽  
Critical Factors ◽  
System 2 ◽  
Common Problems ◽  
Mechanical Components ◽  
Perfusion Experiment ◽  
Selection Of

ABSTRACT Among the critical factors in organ perfusion are (1) the mechanical components of the system, (2) the composition of the perfusate, and (3) the perfusing conditions. In this review, particular consideration is given to the pump, the oxygenator, and cannulas in such systems. Emphasis is placed upon the selection of pertinent equipment for the goals of a particular perfusion experiment, based upon the criteria of adequacy of the perfusion. Common problems in organ perfusion are summarized, and potential solutions to the perfusion problem, involving either biologic or mechanical extracorporeal systems, are suggested.

Transport Characteristics of Wheat Germ Agglutinin-Modified Insulin-Liposomes and Solid Lipid Nanoparticles in a Perfused Rat Intestinal Model

2006 ◽  
Vol 6 (9) ◽  
pp. 2959-2966 ◽  
Author(s):  
Na Zhang ◽  
Qineng Ping ◽  
Guihua Huang ◽  
Xiuzhen Han ◽  
Yanna Cheng ◽  
...  
Keyword(s):  
Solid Lipid Nanoparticles ◽  
Wheat Germ Agglutinin ◽  
Wheat Germ ◽  
Serum Insulin ◽  
Lipid Nanoparticles ◽  
Solid Lipid ◽  
Mucosal Absorption ◽  
Perfusion Experiment ◽  
Absorption Sites

Wheat germ agglutinin (WGA) modified liposomes and solid lipid nanoparticles (SLNs) were evaluated for improving intestinal absorption of insulin. In an in situ local intestinal perfusion experiment, formulations containing 100 IU/kg insulin were administered to the duodenum, jejunum, and ileum of fasted rats. As hypothesized, ileum was the best intestinal location for the absorption of insulin-containing liposomes. Serum insulin concentrations decreased for the various formulations in different absorption sites according to the following trends: Duodenum > ileum > jejunum for WGA-modified insulin-containing liposomes; duodenum > jejunum > ileum for WGA-modified insulin-containing SLNs; ileum > jejunum > duodenum for insulin-containing liposomes; ileum > duodenum > jejunum for insulin-containing SLNs; and duodenum ≥ ileum > jejunum for aqueous solution of insulin. These results imply that the nanoparticle type and delivery site were important factors with respect to increasing the bioavailability of insulin following oral administration. The proteolytic degradation as well as the epithelial permeability were primary determinants influcing insulin mucosal absorption.

A rabbit ear flap perfusion experiment to evaluate the percutaneous absorption of drugs

2004 ◽  
Vol 276 (1-2) ◽  
pp. 29-40 ◽  
Author(s):  
Toshinobu Seki ◽  
Osamu Hosoya ◽  
Tsuyoshi Yamazaki ◽  
Takeshi Sato ◽  
Yuko Saso ◽  
...  
Keyword(s):  
Percutaneous Absorption ◽  
Rabbit Ear ◽  
Perfusion Experiment ◽  
Flap Perfusion

scholarly journals Uptake and metabolism of propionate in the liver isolated from sheep treated with glucagon

1997 ◽  
Vol 77 (5) ◽  
pp. 783-793 ◽  
Author(s):  
Abdulhamid Mohamed Ali ◽  
Markandeya Jois
Keyword(s):  
Jugular Vein ◽  
Isolated Hepatocytes ◽  
Maximal Rate ◽  
Caudal Lobe ◽  
Sterile Saline ◽  
Sheep Liver ◽  
Net Uptake ◽  
Perfusion Experiment ◽  
Uptake And Metabolism ◽  
Stimulation Of

The uptake and metabolism of propionate in the isolated perfused caudal lobe of the liver and in isolated hepatocytes were examined following treatment of sheep with glucagon or saline. Glucagon or sterile saline was infused at 9·8 µg/min for 3 h into the jugular vein and then the caudal lobe of the liver was removed surgically under anaesthesia. The caudal lobe was used either to prepare hepatocytes or in a non-recirculating perfusion experiment. Uptake and metabolism of propionate were studied using [2-14C]propionate. In studies using the non-recirculation perfusion of the caudal lobe of the sheep liver it was shown that the treatment of sheep with glucagon resulted in an increased rate of gluconeogenesis from propionate and in an increased net uptake of propionate by the caudal lobe. The uptake of propionate into the hepatocytes was saturable, concentrative and exhibited a Km for propionate of 0·24 (SE 0·07) mM and a maximal rate of uptake (Vmax) of 6·7 (SE 0·6) nmol/mg dry cells per min and was unaffected by glucagon treatment of sheep. After incubation of cells in medium containing 0·5 mM-[2-14C]propionate for 10 min, the rate of gluconeogenesis from propionate was 22 % higher in the hepatocytes isolated from glucagon-treated sheep. Concentrations in the medium of 1·35 mM butyrate and 1 mM-caproate inhibited propionate uptake by about 50 % and abolished the glucagon-induced stimulation of gluconeogenesis from propionate. The results are consistent with a regulatory role for glucagon in the gluconeogenesis from propionate in the sheep liver.

Coronary Collateral Microcirculation Reserve Becomes Vestigial with Aging

Cardiology ◽  
2020 ◽  
pp. 1-8
Author(s):  
Jiali Chen ◽  
Xiucheng Liu ◽  
Xichun Qin ◽  
Zhiwei Liu ◽  
Lidong Zhu ◽  
...  
Keyword(s):  
Endothelial Nitric Oxide Synthase ◽  
Tissue Injury ◽  
Femoral Vein ◽  
Ischemic Area ◽  
Coronary Collateral ◽  
Ischemic Tissue ◽  
Old Rats ◽  
Perfusion Experiment ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

<b><i>Introduction:</i></b> Our previous study indicated that coronary collateral microcirculation reserve (CCMR), native collaterals, transports blood flow to an ischemic area to reduce ischemic tissue injury. This study aimed to observe the changes of CCMR in the hearts of different month-old rats. <b><i>Methods:</i></b> We selected 2-, 8-, 16-, and 24-month-old rats as the research objects to monitor the changes of CCMR in rats with aging. After acute myocardial infarction, lectin-FITC was injected into the femoral vein vessels of rats to mark CCMR vessels in the ischemic area. <b><i>Results:</i></b> Results of the lectin-FITC perfusion experiment indicated that the number and collagen IV coverage of CCMR vessels declined with aging. Moreover, data suggested a correlation between endothelial nitric oxide synthase and a decline in the number of CCMR vessels. <b><i>Conclusion:</i></b> Aging causes CCMR decline in rats.

scholarly journals Intrapartum transfer of oxytocin across the human placenta: an ex vivo perfusion experiment

Placenta ◽  
2021 ◽  
Author(s):  
Nina Olsén Nathan ◽  
Morten Hedegaard ◽  
Gösta Karlsson ◽  
Lisbeth E. Knudsen ◽  
Line Mathiesen
Keyword(s):  
Human Placenta ◽  
Ex Vivo ◽  
Ex Vivo Perfusion ◽  
Perfusion Experiment

Absorption Mechanism of Cyclosporine A Loaded pH-Sensitive Nanoparticles in Rats

2008 ◽  
Vol 8 (5) ◽  
pp. 2422-2431 ◽  
Author(s):  
Xue-Qing Wang ◽  
Jun-Dong Dai ◽  
Hua Zhang ◽  
Xuan Zhang ◽  
Jian-Cheng Wang ◽  
...  
Keyword(s):  
Dosage Form ◽  
Absorption Mechanism ◽  
Site Specific ◽  
Distribution Study ◽  
P Glycoprotein ◽  
Eudragit S100 ◽  
Intestine Mucosa ◽  
Form Design ◽  
Perfusion Experiment

CyA was prepared into CyA Eudragit S100 nanoparticles (CyA-S100 NP) and the mechanisms of CyA-S100 NP improving the CyA absorption in gastrointestinal tract (GI) were studied systematically in rats. In the GI distribution study, the emptying rates of CyA-S100 NP in duodenum, jejunum, ileum and colon were all lower than these of Neoral®, while in stomach, it was larger than that of Neoral®. In in situ recirculating intestine perfusion experiment, the largest absorption in CyA-S100 NP group occurred in ileum while that in Neoral® group arised in duodenum. The sequence of (AUC0–240 min/A for CyA-S100 NP and Neoral® group was ileum > duodenum > jejunum > colon and duodenum > jejunum > ileum > colon, respectively. CyA in nanoparticles degradated by luminal contents and subcellular fractions were more slowly than these in Neoral®, suggesting the significant protect effect of nanoparticles. Mucoadhesion study in small intestine showed that among all the parts of intestine, CyA-S100 NP exhibited larger mucoadhesive characteristics than Neoral® microemulsion. The sequence of mucoadhesion for CyA-S100 NP group was duodenum > ileum > jejunum and colon, while that for Neoral® group was duodenum > ileum, jejunum and colon, suggesting different site-specific behaves. These results illustrated that nanoparticles increased the absorption of CyA could be attributed to fast stomach empting rate, absorption site specific, small degradation rate by luminal contents, high bioadhension of nanoparticles to intestine mucosa and the use of P-Glycoprotein inhibitor if there is any. This investigation is helpful for the dosage form design for other peptide or protein drugs.

Somatostatin, insulin, and glucagon secretion from isolated perfused pancreas of obese rats

1981 ◽  
Vol 241 (2) ◽  
pp. E146-E150
Author(s):  
S. Seino ◽  
Y. Seino ◽  
J. Takemura ◽  
K. Tsuda ◽  
H. Kuzuya ◽  
...  
Keyword(s):  
Hormone Secretion ◽  
Glucagon Secretion ◽  
Ventromedial Hypothalamus ◽  
Perfused Pancreas ◽  
Isolated Perfused Pancreas ◽  
Insulin And Glucagon Secretion ◽  
Perfusion Experiment ◽  
Pancreatic Hormone ◽  
And Control

A comparison of the somatostatin with the insulin and glucagon secretions in hypothalamic obesity and genetic obesity was made using the isolated perfused pancreas of rats. In our perfusion experiment, the somatostatin response to 19 mM arginine in the presence of 4.4 mM glucose was significantly greater in both ventromedial hypothalamus (VMH)-lesioned and Zucker fa/fa rats than in their controls, as was the perfusate insulin. The perfusate arginine-stimulated glucagon secretion appeared no different in obese and control rats. Because hyperinsulinemia in vivo and hyperresponses to arginine of perfusate insulin and somatostatin were observed in both VMH-lesioned and Zucker fa/fa rats, whereas the perfusate glucagon secretion in the presence of 4.4 mM glucose was unchanged by obesity, the secretory behavior of some pancreatic hormones seems similar in VMH-lesioned and Zucker fa/fa rats in certain conditions. These results suggest that some abnormalities of pancreatic hormone secretion may be caused by a mechanism common to obesity, whether caused experimentally or genetically.

Sign in / Sign up

Export Citation Format

Share Document