scholarly journals In vitro hepatic biotransformation of aldrin and dieldrin in food-producing animals

2001 ◽  
Vol 49 (3) ◽  
pp. 349-353
Author(s):  
N. Furusawa ◽  
Y. Morita
Keyword(s):  
No Reduction ◽  
Laying Hens ◽  
Female Cattle ◽  
Hepatic Biotransformation

The hepatic biotransformation of aldrin (AD) and dieldrin (DD) was studied in liver post-mitochondrial supernatants (S-9s) from laying hens, female cattle and swine. S-9s were incubated with 0.03 nmol o f AD or DD for 1 h. After 1 h, AD in the samples was almost epoxidated to DD. This formation was found with all the animal S-9s, and the highest rates occurred in pig S-9 (P < 0.01), followed by cow and hen S-9s. No reduction of DD was found with any of the S-9s.

scholarly journals HEPATIC BIOTRANSFORMATION PROFILES OF SULPHAMONOMETHOXINE IN FOOD-PRODUCING ANIMALS AND RATS IN VITRO

2000 ◽  
Vol 48 (3) ◽  
pp. 293-300 ◽  
Author(s):  
N. Furusawa
Keyword(s):  
Laying Hens ◽  
Female Cattle ◽  
Hepatic Biotransformation

Hydroxylation and acetylation of sulphamonomethoxine (SMM) and deacetylation of N4-acetyl SMM (N4-AcSMM) were estimated in liver post-mitochondrial supernatants (S-9) from laying hens, female cattle, swine and rats. The formation of hydroxylated SMM, 2,6-dihydroxy SMM (2,6-diOH-SMM), was found only with hen S-9s. N4-acetylation rate of SMM was the highest in pig S-9s, followed by rat, then hen or cow S-9s. All S-9s from the four species deacetylated N4-AcSMM. In hen S-9s, the rate of 2,6-dihydroxylation was higher during incubation at 41 °C than at 37 °C.

Inhibition of Hepatic Microsomal Drug Metabolism by the Hydrazines Ro 4-4602, MK 486, and Procarbazine Hydrochloride

1972 ◽  
Vol 50 (7) ◽  
pp. 721-724 ◽  
Author(s):  
Norman R. Bade ◽  
Stuart M. MacLeod ◽  
Kenneth W. Renton
Keyword(s):  
Drug Interaction ◽  
Drug Metabolism ◽  
Sleeping Time ◽  
Hydrazine Derivatives ◽  
Significant Drug Interaction ◽  
Microsomal Drug Metabolism ◽  
Clinically Significant ◽  
Hepatic Biotransformation

Preliminary experiments were undertaken to examine the effect of three hydrazine derivatives, viz. Ro 4-4602, MK 486, and procarbazine hydrochloride, on hepatic microsomal drug metabolism in rats. All three compounds when given as pretreatment significantly prolonged pentobarbital sleeping time. In vitro, the hepatic microsomal N-demethylation of aminopyrine was inhibited. It is concluded that all three drugs are possible sources of clinically significant drug interaction when administered in combination with other agents which undergo hepatic biotransformation.

Breed Differences In The Expression Levels Of Gga-Mir-222a In Laying Hens Influenced H2S Production By Regulating Methionine Synthase Genes In Gut Bacteria

2020 ◽  
Author(s):  
Sicheng Xing ◽  
Chunbo Huang ◽  
Ruiting Wu ◽  
Yiwen Yang ◽  
Jingyuan Chen ◽  
...  
Keyword(s):  
Laying Hens ◽  
Expression Profiles ◽  
Gas Production ◽  
Methionine Synthase ◽  
Differentially Expressed ◽  
Cecal Content ◽  
Differentially Expressed Mirnas ◽  
Microbial Genes ◽  
H2s Production

Abstract Background: The microbiota in the cecum of laying hens was critical for host digestion metabolism and odor gas production. Recent studies have suggested that host miRNAs could regulate gene expression in the gut microbiota. The expression profiles of host-derived miRNAs in the cecal content of two laying hen breeds, Hy-line Gray and Lohmann Pink, which have dissimilar H2S production were characterized, and their possible effects on H2S production by regulating the expression of related genes in the microbiota were demonstrated. Results: The differential expression of microbial serine O-acetyltransferase, methionine synthase, aspartate aminotransferase, methionine-gamma-lyase and adenylylsulfate kinase between the two breeds resulted in lower H2S production in the Hy-line hens. The results also demonstrated miRNA exosomes in the cecal content of laying hens and the potential miRNA-target relationships between 9 differentially expressed miRNAs and 9 differentially expressed microbial genes related to H2S production were investigated, among which gga-miR-222a targeted two methionine synthase genes, Odosp_3416 and BF9343_2953. An in vitro fermentation experiment showed that gga-miR-222a upregulated the expression of these genes, which increased methionine concentrations but decreased H2S production and soluble sulfide concentrations, indicating the potential of host-derived gga-miR-222a to reduce H2S emission in laying hens. Conclusion: These findings identify both a physiologic role by which miRNA shapes the cecal microbiota of laying hens and a strategy to use host miRNAs to manipulate the microbiome and actively expressed key microbial genes to reduce H2S emission and breed environmentally friendly laying hens.

Stable Phenotypic Resistance of CandidaSpecies to Amphotericin B Conferred by Preexposure to Subinhibitory Levels of Azoles

1998 ◽  
Vol 36 (9) ◽  
pp. 2690-2695 ◽  
Author(s):  
Jose A. Vazquez ◽  
Maria T. Arganoza ◽  
Dina Boikov ◽  
Stephanie Yoon ◽  
Jack D. Sobel ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Clinical Setting ◽  
Fungicidal Activity ◽  
No Reduction ◽  
Growth Conditions ◽  
In Vitro Assays ◽  
In Vitro Susceptibility ◽  
Phenotypic Resistance ◽  
Time Period

The fungicidal activity of amphotericin B (AmB) was quantitated for several Candida species. Candida albicans andC. tropicalis were consistently susceptible to AmB, with less than 1% survivors after 6 h of exposure to AmB. C. parapsilosis and variants of C. lusitaniae andC. guilliermondii were the most resistant, demonstrating 50 to 90% survivors in this time period and as high as 1% survival after a 24-h exposure time. All Candida species were killed (<1% survivors) after 24 h of exposure to AmB. In contrast, overnight exposure to either fluconazole or itraconazole resulted in pronounced increases in resistance to subsequent exposures to AmB. Most dramatically, C. albicans was able to grow in AmB cultures after azole preexposure. Several other Candida species did not grow in AmB but showed little or no reduction in viability after up to 24 h in AmB. Depending on the growth conditions,Candida cells preexposed to azoles may retain AmB resistance for days after the azoles have been removed. If this in vitro antagonism applies to the clinical setting, treatment of patients with certain antifungal combinations may not be beneficial. The ability of some Candida isolates to survive transient exposures to AmB was not reflected in the in vitro susceptibility changes as measured by standard MIC assays. This finding should be considered in studies attempting to correlate patient outcome with in vitro susceptibilities of clinical fungal isolates. Patients who fail to respond to AmB may be infected with isolates that are classified as susceptible by standard in vitro assays but that may be resistant to transient antifungal exposures which may be more relevant in the clinical setting.

scholarly journals In vitro hepatic biotransformation of the algal toxin pectenotoxin-2

Toxicon X ◽  
2020 ◽  
Vol 6 ◽  
pp. 100031
Author(s):  
Morten Sandvik ◽  
Christopher O. Miles ◽  
Alistair L. Wilkins ◽  
Christiane Fæste
Keyword(s):  
Algal Toxin ◽  
Hepatic Biotransformation ◽  
Pectenotoxin 2

scholarly journals Hydrolysis of plasma triacylglycerol-rich lipoproteins from immature and laying hens (Gallus domesticus) by lipoprotein lipase in vitro

1982 ◽  
Vol 206 (3) ◽  
pp. 647-654 ◽  
Author(s):  
H Griffin ◽  
G Grant ◽  
M Perry
Keyword(s):  
Lipoprotein Lipase ◽  
Lipid Composition ◽  
Laying Hens ◽  
Laying Hen ◽  
Dietary Lipid ◽  
Gallus Domesticus ◽  
High Density Lipoproteins ◽  
Plasma Triacylglycerol ◽  
Hydrolysis Of

Very-low-density (VLD) lipoproteins and portomicrons were isolated from the plasma of immature and laying hens and their size, lipid composition and susceptibility to hydrolysis by lipoprotein lipase were compared. In agreement with other studies, VLD lipoproteins from laying hens were found to be smaller and have a different lipid composition than VLD lipoproteins from immature hens. Portomicrons from immature and laying hens had mean diameters of about 150 nm and similar lipid compositions. Hydrolysis of VLD lipoproteins from immature hens, and portomicrons from immature and laying hens, proceeded rapidly until at least 40% of the substrate had been used. In contrast only 1-15% of laying-hen VLD-lipoprotein triacylglycerol was readily hydrolysis occurred slowly. The limited susceptibility of laying-hen VLD lipoproteins appeared to be due to their low content of lipoprotein lipase activator apoprotein, which occurred despite an abundance of activator in the high-density lipoproteins of laying-hen plasma. The results provide further evidence that the liver of the laying hen synthesizes specialized lipoproteins. Their limited susceptibility to hydrolysis by lipoprotein lipase is probably a major factor in ensuring transport of lipid to yolk rather than to other tissues. The form of transport of dietary lipid, however, is similar in immature and laying hens.

scholarly journals Efficacy of Telavancin in a Rabbit Model of Aortic Valve Endocarditis Due to Methicillin-Resistant Staphylococcus aureus or Vancomycin-Intermediate Staphylococcus aureus

2005 ◽  
Vol 49 (8) ◽  
pp. 3163-3165 ◽  
Author(s):  
Andres G. Madrigal ◽  
Li Basuino ◽  
Henry F. Chambers
Keyword(s):  
Staphylococcus Aureus ◽  
Aortic Valve ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
No Reduction ◽  
Rabbit Model ◽  
Daily Regimen ◽  
Methicillin Resistant ◽  
Days Of Therapy ◽  
Time Kill

ABSTRACT The activities of telavancin and vancomycin were compared in vitro and in the rabbit model of aortic valve endocarditis against a methicillin-resistant Staphylococcus aureus strain, COL, and a vancomycin-intermediate S. aureus (VISA) strain, HIP 5836. Telavancin was bactericidal in time-kill studies at a concentration of 5 μg/ml against both COL and HIP5836. Vancomycin was bacteriostatic at 5 μg/ml and bactericidal at 10 μg/ml against COL and was bacteriostatic at 10 μg/ml against VISA strain HIP 5836. Compared to untreated controls, a twice-daily regimen of 30 mg/kg of telavancin reduced mean aortic valve vegetation titers of the COL strain by 4.7 log10 CFU/g after 4 days of therapy and sterilized 6/11 vegetations compared to 3.4 log10 CFU/g with 3/10 vegetations sterilized for a regimen of twice-daily vancomycin, 30 mg/kg; these differences were not statistically significant. Telavancin was significantly more effective than vancomycin in the VISA model, producing a 5.5 log10 CFU/g reduction versus no reduction in CFU with vancomycin. In experiments comparing 2-day regimens of telavancin at 30 mg/kg and 50 mg/kg twice daily, organisms were rapidly eliminated from vegetations, but the effect was not different between the two doses. These results suggest that telavancin may be an effective treatment for endocarditis and other serious staphylococcal infections accompanied by bacteremia, including infections caused by staphylococci not susceptible to vancomycin.

Changes in the hypothalamic contents of LHRH-I and -II and in pituitary responsiveness to synthetic chicken LHRH-I and -II during the progesterone-induced surge of LH in the laying hen

1990 ◽  
Vol 127 (3) ◽  
pp. 487-496 ◽  
Author(s):  
S. C. Wilson ◽  
R. A. Chairil ◽  
F. J. Cunningham ◽  
R. T. Gladwell
Keyword(s):  
Plasma Concentration ◽  
Pituitary Gland ◽  
Laying Hens ◽  
Plasma Concentrations ◽  
Posterior Hypothalamus ◽  
Anterior Hypothalamus ◽  
Significant Fall ◽  
Basal Plasma

ABSTRACT The contents of LHRH-I and -II in the anterior hypothalamus and posterior hypothalamus (including the mediobasal hypothalamus and median eminence) were measured at 90, 180 and 360 min after the i.m. injection of laying hens with progesterone. Whilst no changes were observed in the content of LHRH-I in the anterior hypothalamus, LHRH-I in the posterior hypothalamus tended to fall at 90 and 180 min after injection of progesterone in hens maintained on 16 h light:8 h darkness (16L:8D) and 8L:16D respectively. Pretreatment of laying hens with tamoxifen significantly increased the hypothalamic contents of LHRH-I and -II, raised the basal plasma concentration of LH and modified the LH response to progesterone injection. In hens in which tamoxifen prevented an increase in the plasma concentration of LH after progesterone injection, the content of LHRH-I in the posterior hypothalamus remained unchanged. In contrast, in hens in which progesterone stimulated a steep increase in LH within 90 min, there was a pronounced and significant fall in LHRH-I content of the posterior hypothalamus. No change in the hypothalamic content of LHRH-II was observed during the progesterone-induced surge of LH until plasma concentrations had attained maximal values or started to decline. Then, in hens maintained on 16L:8D, a significant fall in the content of LHRH-II in the anterior hypothalamus was found at both 180 and 360 min after injection with progesterone. Tests in vitro and in vivo of the responsiveness of the pituitary gland to synthetic LHRH-I and -II revealed no change at 90 min after injection of laying hens with progesterone, when plasma concentrations of LH were increasing, but a pronounced reduction when plasma LH concentrations were maximal or falling. These results suggest that LHRH-I mediates in the progesterone-induced increase in the plasma concentration of LH. Although the subsequent decline in plasma LH was associated with a reduced responsiveness of the pituitary gland to LHRH, a significant correlation between the contents of LHRH-I and -II in the anterior hypothalamus and a fall in the hypothalamic content of LHRH-II when plasma LH was maximal or declining allows the possibility of an involvement of this peptide in the neuroendocrine events preceding ovulation. Journal of Endocrinology (1990) 127, 487–496

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