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1
Content available remote Pharmacokinetics of ebeiedinone in mouse blood by UPLC–MS/MS
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EN
An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established to determine ebeiedinone in mouse blood, and the pharmacokinetics of ebeiedinone after intravenous (0.5 mg/kg) and oral (2, 4, and 8 mg/kg) administration was studied. Twenty-four mice were randomly divided into 4 groups, 1 group was for intravenous administration (0.5 mg/kg), and other 3 groups were for oral administration (2, 4, and 8 mg/kg), with 6 rats in each group. Yubeinine was used as an internal standard. Multiple reaction monitoring (MRM) mode was used to quantitatively analyzed ebeiedinone m/z 414.4 → 91.1 and the internal standard m/z 430.4 → 412.3 in the electrospray ionization (ESI) positive interface. In the concentration range of 1–2000 ng/mL, the ebeiedinone in the mouse blood was linear (r2 > 0.995), and the lower limit of quantification was 1.0 ng/mL. In the mouse blood, the intra-day precision coefficient of variation (CV) was less than 15%, and the inter-day precision CV was less than 15%. The accuracy ranged from 85.4% to 114.6%, and the average recovery was higher than 61.3%. The matrix effect was between 87.0% and 106.5%. These data met the pharmacokinetic study requirements of ebeiedinone. The UPLC–MS/MS method was sensitive, rapid, and selective and was successfully applied to the pharmacokinetic study of ebeiedinone in mice. The absolute bioavailability of ebeiedinone was 30.6%.
EN
An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established to determine the hapepunine in mouse blood, and the pharmacokinetics of hapepunine after intravenous (1.0 mg/kg) and intragastric (2.5, 5, and 10 mg/kg) administrations was studied. Delavinone was used as an internal standard. The UPLC ethylene bridged hybrid (BEH) C18 column was used for chromatographic separation. The mobile phase consisted of acetonitrile and 0.1% formic acid with a gradient elution flow rate of 0.4 mL/min. Multiple reaction monitoring (MRM) mode was used for quantitative analysis of hapepunine in electrospray ionization (ESI) positive interface. Proteins from mouse blood were removed by acetonitrile precipitation. The verification method was established in accordance with the US Food and Drug Administration (FDA) bioanalytical method validation guidelines. In the concentration range of 1–1000 ng/mL, the hapepunine in the mouse blood was linear (r2 > 0.995), and the lower limit of quantification was 1.0 ng/mL. In the mouse blood, the intra-day precision coefficient of variation (CV) was less than 12%, the inter-day precision CV was less than 14%. The accuracy ranged from 91.7% to 109.3%. The average recovery was higher than 76.7%, and the matrix effect was between 86.0% and 106.4%. The UPLC–MS/MS method was sensitive, rapid, and selective and was successfully applied to the pharmacokinetic study of hapepunine in mice. The absolute bioavailability of hapepunine was 22.0%.
EN
Activity of spleen lymphocytes derived from T. spiralis-infected C3H/w mice in the local GvH reaction was assessed using the popliteal lymph node GvH assay. It was found that splenocytes obtained on day 10 of the infection were substantially more active in the reaction than the spleen cells collected from uninfected donors. This effect correlated inversely with the infectious dose of the parasite, i.e. cells obtained from mice infected with 500 larvae per mouse were less efficient stimulators of the GvH reaction than splenocytes isolated from mice infected with 200 larvae per mouse. On day 30 of the infection activity of spleen T cells in the GvH reaction was suppressed in comparison to the control splenocytes but on day 60 post infection this activity returned to the baseline level. The above variations in the activity of splenic T lymphocytes in the local GvH reaction were readily quantitated by comparison of the three appropriate parameters assessed in the popliteal lymph nodes of both the infected and control animals and expressed as the mass, cellularity, and proliferation coefficients, respectively.
5
Content available remote Pharmacokinetics and bioavailability of curdione in mice by UPLC-MS/MS
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EN
A UPLC-MS/MS method was developed to determinate curdione in the mouse blood, and the pharmacokinetics of curdione in mice after intravenous (5 mg kg⁻¹) and oral (20 mg kg⁻¹) administration were studied. The HSS T3 column was used for separation, and column temperature was set at 40 °C. Multiple reaction monitoring (MRM) mode were used for determination of curdione. Blood samples were taken from the caudal vein of Institute of Cancer Research (ICR) mice after administration of curdione. It showed a good linear relationship in the range of 1–500 ng mL⁻¹ (r > 0.998); the intra-day precision was <13%, the inter-day precision was <15%, and the accuracy was 90%–105%, the recovery was >77%, and the matrix effect was 97%–107%. The half-life was relatively short, and the bioavailability was 6.5%. The developed method was suitable for the pharmacokinetics of curdione in mice.
6
Content available remote Pharmacokinetics of 8-O-acetylharpagide in mouse blood by UPLC–MS/MS
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EN
8-O-Acetylharpagide is the main active component of the herb Ajuga decumbens, which possesses anti-tumor, anti-virus, and anti-inflammation properties. In this study, ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) was used to measure the concentration of 8-O-acetylharpagide in mouse blood, with subsequent investigation of the pharmacokinetics of the drug after intravenous or oral administration. Shanzhiside methyl ester was used as an internal standard, and the acetonitrile precipitation method was used to process the blood samples. Chromatographic separation was achieved using an ultra-performance liquid chromatography ethylene-bridged hybrid (UPLC BEH) column (2.1 mm × 50 mm, 1.7 μm) with a gradient methanol–water mobile phase (containing 0.1% formic acid). The flow rate was 0.4 mL/min, and the elution time was 5.0 min. 8-O-Acetylharpagide was quantitatively measured using electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization. The result indicated that, within the range of 5–500 ng/mL, the linearity of 8-O-acetylharpagide in mouse blood was satisfactory (r > 0.995), and the lower limit of quantification (LLOQ) was 5 ng/mL. Intra-day precision relative standard deviation (RSD) of 8-O-acetylharpagide in blood was lower than 9%, and the inter-day precision RSD was lower than 13%. The accuracy range was between 94.3% and 107.1%, average recovery was higher than 91.3%, and the matrix effect was between 100.8% and 110.8%. This analytical method was sensitive and fast with good selectivity and was successfully applied to perform pharmacokinetic studies of 8-O-acetylharpagide in mice. The bioavailability of 8-O-acetylharpagide was 10.8%, and the analysis of the primary pharmacokinetic parameters after oral and intravenous administration indicated that 8-O-acetylharpagide had a significant first pass effect after oral administration.
EN
Eugenitin is a non-volatile chromone derivative which is always found in dried flower buds of Syzygium aromaticum L. (Merr.) & L.M. Perry. Until now, there were no reports about the pharmacokinetics of eugenitin in biological fluids. A UPLC-MS/MS method developed to determine eugenitin in mouse blood. The blood samples were prepared by protein precipitation with acetonitrile. Chrysin (internal standard, IS) and eugenitin were gradient eluted by mobile phase of acetonitrile and water (0.1% formic acid) in a BEH C18 column. The multiple reaction monitoring (MRM) of m/z 221.1→206.0 for eugenitin and m/z 255.1→152.9 for IS with an electrospray ionization (ESI) source was used for quantitative detection. The calibration curve ranged from 0.5 to 500 ng/mL (r > 0.995). The accuracy ranged from 98 to 113%, the precision was less than 12%, and the matrix effect was between 86 and 94%, the recovery was better than 81%. The developed method was successfully used for pharmacokinetics of eugenitin in mice after intravenous (5 mg/kg) and oral (20 mg/kg) administration, and the absolute availability of eugenitin was 12%.
EN
The aim of the study was to determine the effect of the application of hyperbaric oxygen therapy on the course of an infection with group A type T-3 hemolytic β streptococcus. Experiments were carried out on Porton white mice and in vitro blood plates. General and local infections with streptococci were induced in animals. The infected animals were treated with hyperbaric oxygenation. The lethal effect of infection was significantly inhibited using hyperbaric oxygenation on the first and second day following the infection.
9
88%
EN
An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed and validated for quantification of ligustroflavone, which was then applied in pharmacokinetics study in rat and tissue distribution in mouse. Twelve male Sprague Dawley rats were used for pharmacokinetics after intravenous (2 or 8 mg/kg) administration of ligustroflavone, six rats for each dose. Twenty-five mice were randomly divided into 5 groups (5 mice for each group, 1 group for each time point) and received 16 mg/kg ligustroflavone via intraperitoneal administration. The linear range of the calibration curve was over 2–2000 ng/mL for ligustroflavone in rat plasma and mouse tissues. The intra-day and inter-day precision expressed in % RSD were less than 14%, and the accuracy was between 88.5% and 108.4%.
EN
In this report we present effect of pizotifen, an antagonist of serotonin (5-hydroxytryptamine; 5-HT) receptors, on P-induced convulsions in mice. Experiments were conducted on male mice Balby. Convulsive effect P was determined using the following measures: percentage of mice with seizures, the number of seizure episodes/2 h, the latency time of the beginning P-induced seizure activity in mice and P-induced seizure activity of mice determined by score of Racine. Pretreatment mice with pizotifen (0.5 mg/kg ip) did not prevent convulsive effect P, applied ip at the dose of 50 μmol/kg ip (59.3 mg/kg) but significantly shortened the latency time of the beginning of P-induced seizure activity of mice. We conclude that central serotonin receptors are involved in the mechanism of P-induced convulsions.
EN
Preliminary results of Magnetic Resonance Imaging (MRI) of cardiac function in mice in vivo, using the homebuilt gradient coils and specialized RF probehead are demonstrated. An unshielded gradient system with inner diameter of 60 mm was designed and constructed for the 4.7T/310 magnet with MARAN DRX console (Resonance Instruments). Dedicated probehead, constructed to fit the gradient system, consists of the RF birdcage coil and the animal handling system. ECG-triggered cine images of eight FVB (wild-type) and four transgenic micewith heart failure (Tg alfa q*44) were acquired at physiological temperature (37 graduate C) with a good quality of multislice images in different phases of the cardiac cycle, as well as a good contrast between myocardium and flowing blood. This technique allowed the calculation of the end-diastolic (EDV) and end-systolic (ESV) volumes of working heart that could be used to monitor the development of heart failure in vivo in Tg alfa q*44 mice.
EN
In this study, maternal toxicity and developmental effects of exposure to Ascaris trypsin inhibitor were evaluated in mice. Pregnant BALB/c females were injected intraperitoneally by Ascaris inhibitor /AIT/ at 200, 300, and 400 mg/kg body weight/day, on days 12 to 15 of gestation (stage of fetal development). At day 19 of pregnancy, uterine contents were inspected for implantation sites, early resorptions (moles), living fetuses and dead fetuses. The living fetuses were weighed and examined for external, internal and skeletal abnormalities. The results showed that AIT induced maternal toxicity, evidenced by maternal deaths, abortions, bleeding from uterus and reduced body weight gain as compared to control (p <0.01). There were no differences between the control group and the rest of all groups investigated for total implantation sites and early resorptions. Fetotoxicity was observed as shown by the decrease in the number of living fetuses and mean fetal weight, a high rate of intrauterine fetal deaths, delayed skeletal ossification, occurrence of pathological changes of fetal organs and tissues. Only one type of congenital malformations (hydronephrosis) was noted in fetuses after injection of higher doses of AIT.
EN
The present study has examined the level of total IgA and antigen-specific IgA antibodies in serum and bile in various inbred strains of mice infected with Trichinella spiralis. These strains of mice differ in the speed at which they expel the adult worms from the gut. BALB/c and CBA mice expel adult worms faster than C3H and C57BL/6 mice. However, the CBA strain of mice is more resistant to the establishment of an initial infection of T. spiralis than BALB/c mice. While total serum IgA and bile sIgA concentrations correlated with the time course of the expulsion of adult worms, there was no similar correlation between IgA concentrations and the intensity of T. spiralis infection during the muscle phases of infection in any of the strains of mice investigated. Specific IgA antibodies in sera and sIgA antibodies in bile were measured by ELISA in C57BL/6 mice using crude somatic L1 muscle larvae (AgL1) and crude adult worm (AgAd) antigens. A pronounced increase in sIgA antibodies to AgL1 antigen was found by day 9 of infection in bile. However, a gradual increase in IgA in serum to AgAd antigen was observed from 6 till 24 DAI. Specific IgA response in serum to AgAd was much higher than to AgL1 and, in contrast the sIgA response in bile, was more pronounced to AgL1 than to AgAd. This result suggests that bile may also provide a valuable source of sIgA.
EN
Cross-resistance between Toxocara canis and Trichinella spiralis was studied in CBA/J mice exposed to varying doses of T. canis and 14 days later challenged with 400 larvae of T. spiralis. Intestinal burden of T. spiralis on day 7 post infection (PI) in mice given 25 ova of T. canis was 70% of challenge control burden, but in mice given 250 ova the burden was consistently below 20% of the control value. Male worms were preferentially expelled from mice exposed to T. canis. Recovery of muscle larvae was reduced in mice given 250 ova, but not in mice given 25 ova. Intestinal burdens of T. spiralis in T. canis-sensitized mice (250 ova) was 58% of the control values at 36 h PI, and most of the remaining worms were expelled between 5 and 7 days PI. Worms from mice given 250 ova released lower numbers of newborn larvae in vitro.
EN
Recently the increasing prevalence of gastrointestinal diseases, including neoplasm, has resulted in the necessity of characterising not only the tumours, but also healthy mucosa. Research into the morphological changes of healthy mucosa under different experimental conditions, including drugs, special diets and the use of probiotic bacteria, is greatly facilitated by the availability of animal models. In spite of the widespread use of mice in gastrointestinal research, there is a lack of information on the qualitative and quantitative histological characteristics of the intestinal mucosa of the mouse. The aim of this study was to assess the morphological characteristics and the postnatal development of the small intestine of wild type mice — C57BL/6J. The mice were aged either 5 weeks or 12 weeks. The 12-week-old mice had been weaned at the age of 5 weeks. After dissection the small intestine was divided into 5 equal portions and randomly chosen microscopical sections from each were stained with haematoxylin and eosin. The parameters describing the morphology of the small intestine (villus height, depth of the crypt, villus width near the crypt, width of the villus connective tissue near the crypt, thickness of the muscular layer and the height of the enterocytes and their nuclei) were evaluated under a light microscope. In both age groups the height and width of the villi decreased, while the thickness of the muscular layer increased in the distal direction. The height of the enterocytes decreased and the height of the enterocyte nucleus increased towards the colon in both age groups. The depth of the crypts was greater in the younger animals than in the older ones. Our data provides the baseline morphological description of the small intestinal mucosa in wild type mice, strain C57BL/6J, which can be used as a reference for testing the influence of drugs, toxins, nutrients and inborn mutations on the mouse intestine.
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