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Heparin-like biomacromolecules (HepLBm), exhibiting similar chemical structure and biological properties to heparin, can be obtained by modifying either synthetic biopolymers or natural biomacromolecules with physical or chemical methods. In this work, a low-cost and biocompatible sodium alginate was chosen as a model biomacromolecule to design anticoagulant HepLBm with a similar sulfation degree to heparin. FTIR, 1H NMR, and element analysis data were used to confirm the chemical structure of HepLBm. Hemolysis tests, clotting time, complement activation, and contact activation tests were carried out to determine the in vitro anticoagulant activity of HepLBm. In addition, systematic studies of blood cell count, coagulation function, and histopathology were performed to demonstrate the in vivo anticoagulant activity and toxicity of HepLBm with SD rat experiments. Furthermore, a series of linear molecules containing carboxyl groups, sulfonic groups, and hydroxyl groups were selected and their clotting time was tested to provide a mechanism analysis for the excellent anticoagulant activity of HepLBm. With the excellent in vitro/in vivo anticoagulant activity, good biocompatibility, and low cost, the HepLBm synthesized in this work would have great potential for substitution of heparin in many application fields, such as the surface modification of biomedical devices, extracorporeal anticoagulants, and other clinical fields.

Background: Gonadotropin-releasing hormone analogs (GnRHas) are used for treating central precocious puberty (CPP). However, their roles in the regulation of immune cells especially regulatory T cells (Tregs) remains elusive. Therefore, we characterized buserelin-induced phenotypical and functional changes of Tregs.Methods: A rat CPP model was established followed by administration of buserelin acetate. Flow cytometry was used to evaluate the expression of functional molecules in splenic Tregs. The suppressive activity of Tregs was determined by the suppression assay. GnRHR expression in Tregs was assessed by flow cytometry analysis and Immunoblotting. Normal Tregs were then stimulated and treated with buserelin acetate in vitro. After that, Foxp3 expression, Treg proliferation, and cytokine production were analyzed by flow cytometry. Intracellular signaling was evaluated by Immunoblotting, and Treg function was determined by the suppression assay.Results: After in vivo buserelin treatment, the frequency of splenic Tregs was decreased, with the reduction in the expression of Foxp3, IL-10, and TGF-β. The suppressive activity of Tregs was weakened. Buserelin down-regulated Foxp3 expression while promoting the expression of RORγt and IL-17 in Tregs through activating the protein kinase A (PKA) pathway in vitro. The PKA inhibitor H-89 abolished the effect of buserelin and enhanced Treg function.Conclusion: Buserelin impaired the immunosuppressive activity of Tregs through the PKA signal pathway. Buserelin-induced activation of PKA signaling down-regulated Foxp3 expression while promoting RORγt expression in Tregs, and subsequently weakened Treg function. Our study indicates the necessity of monitoring Treg activity in CPP patients to avoid potential autoimmunity or inflammation.

To assess the value of contrast-enhanced ultrasound (CEUS) and color Doppler ultrasound (DUS) on hemodynamic changes and cerebral perfusion quantitative analyses in Sprague-Dawley (SD) rats with focal permanent ischemic stroke.Sixteen SD rats with thin skulls were subjected to establish middle cerebral artery occlusion (MCAO) model. CEUS images were performed before modeling (TA total of 12 rats were successfully modeled and completed with mNSS score 9-11. No blood flow signals were observed on the right MCA and ACA in the 12 rats at TCEUS and DUS can reveal the intracranial hemodynamics and brain tissue perfusion trends of MCAO rats, which could be new methods in assessment of ischemic stroke model at multiple time points.

To determine the value of applying multimodal ultrasound (mUS) in SD rats of cerebral ischemic model at super early stage (5-15 min after modeling).Fifteen focal cerebral ischemic models were established in SD rats with thinning skulls using the suture method. Gray-scale ultrasound, contrast-enhanced ultrasound, and enhanced color Doppler (CECDUS) were performed before and immediately after the modeling to observe the location of the in-cranial suture, perfusion of the right hemisphere, and color flow signal of the middle cerebral artery and the anterior cerebral artery, respectively.A modified neurological deficit score (mNSS) and 2, 3, 5-triphenyltetrazolium chloride (TTC) stains were obtained three hours later to confirm the successful modeling as the gold standard. The positive rate detected by mUS was compared with the gold standard using McNemar tests.One rat died and 14 rats completed the experiment.mUS imaging detected 71% (10/14) positive signals, no significant difference compared with the gold standard (64%, 9/14) (Multimodal ultrasound can assess modeling success quickly and accurately immediately after the establishment of ischemic model of SD rats.

A rapid, sensitive and simple liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the simultaneous determination of yogliptin and its metabolite in Wistar rat plasma. Linagliptin and dexamethasone were chosen as the internal standards of yogliptin and its metabolite, (R)-8-(3-hydroxypiperidine- -yl)-7-(but-2-yn-1-yl)-1-((5-fluorobenzo[d]thiazol-2-yl)methyl)-3-methyl- H-purine-2, 6 (3H, 7H)-dione, respectively. After a simple protein precipitation using acetonitrile as the precipitating solvent, both analytes and ISs were separated on a Grace Altima HP C18 column (2.1 mm x 50 mm, 5 microm) with gradient elution using methanol (containing 0.1% formic acid, 4 mmol x L(-1) ammonium acetate)-0.1% formic acid (containing 4 mmol x L(-1) ammonium acetate) as the mobile phase. A chromatographic total run time of 4.4 min was achieved. Mass spectrometric detection was conducted with electrospray ionization under positive-ion and multiple-reaction monitoring modes. Linear calibration curves for yogliptin and its metabolite were over the concentration range of 0.5 to 500 ng x mL(-1) with a lower limit of quantification of 0.5 ng x mL(-1). The intra- and inter- assay precisions were all below 14%, the accuracies were all in standard ranges. The method was used to determine the concentration of yogliptin and M1 in Wistar rat plasma after a single oral administration of yogliptin (27 mg x kg(-1)). The method was proved to be selective, sensitive and suitable for pharmacokinetic study of yogliptin and M1 in Wistar rat plasma.

Gastric cancer (GC) is one of the most common malignancies in China. B-cell translocation gene 3 (BTG3) has been identified as a tumor suppressor in several tumors, but its role in GC remains unknown. This study aimed to detect the expression of BTG3 and its prognostic value in GC tissues and determine its function in the progression of GC.The expression of BTG3 was detected in GC cell lines and tissues by real-time RT-PCR, Western blot or immunohistochemistry. A series of in vitro and in vivo assays were performed to evaluate the effect of BTG3 on proliferation, migration and invasion of GC cells.B-cell translocation gene 3 was obviously down-regulated in GC tissues. Its expression was positively correlated with distant metastasis (P0.05). Patients with lower BTG3 expression had shorter overall survival time (P = 0.015). BTG3 suppressed the proliferation of GC cells in vitro and in vivo. It also inhibited migration and invasion of GC cells in vitro.Down-regulation of BTG3 is closely associated with proliferation, migration and invasion in GC. It may be a novel prognostic biomarker for GC patients.

We have shown that the addition of cholestyramine (CHA, a resin known to bind bile salts in the gastrointestinal tract) to ochratoxin A (OTA)-contaminated rat diets reduced plasma levels of the toxin and prevented OTA-induced nephrotoxicity. To elucidate the mechanism of action of CHA, we carried out in vitro experiments to determine whether the resin may bind the toxin. For comparative purposes, binding of bile salts to the resin was also examined. Results showed that CHA binds both OTA and bile salts (taurodeoxycholate [TDC] and taurocholate [TCA]). Also, CHA showed greater affinity for OTA and TDC than for TCA. At 1 mM concentration, 96% of OTA and 80% of TDC were bound to the resin, while for TCA binding was only 50%. However, saturation of the resin was reached at higher levels with bile acids compared to OTA (3.67 mmol/g resin for TCA and 3.71 mmol/g resin for TDC versus 2.85 mmol/g resin for OTA). To characterize the nature of the binding of the toxin to CHA, NaCl (0 to 200 mM) was added to a fixed amount of OTA or bile acids. As expected, TCA absorption was decreased by the addition of NaCl (50 mM), indicating electrostatic binding. However, OTA and TDC sorption was decreased only at high concentrations of NaCl (150 mM), suggesting a stronger binding to the resin than that shown with TCA. Sequential competitive studies demonstrated that CHA binds more OTA than TCA. The results of the in vivo study show the role of bile salts in OTA absorption. The toxin's plasma levels at 1 and 3 h after a single oral dose of OTA were significantly decreased in bile salt-depleted rats compared to the control. Thus, the alteration of the bile salt biliary pool and OTA enterohepatic circulation may be an additional mechanism of action of the resin against mycotoxin toxicity.

Healthy Beagle dogs were administrated with batroxobin by intravenous infusion at high, medium and low doses. The study of pharmacodynamics and pharmacokinetics was intended to clarify the relevance of them and provided strong evidence for clinical use of batroxobin. The blood samples were collected after injection based on the time schedule and samples were tested by ELISA method to get the concentration of batroxobin. At the same time, changes of prothrombin time (PT), thrombin time (TT), activated partial thromboplastin time (APTT), fibrinogen (Fib) and D-dimmer were tested. The results showed that the concentration of D-D increased significantly after administration compared with that of before administration. The main pharmacokinetic parameters were as follows: t1/2 were (2.27 +/- 0.42) h, (10.65 +/- 2.19) h and (11.01 +/- 3.51) h; C(max) were (11.9 +/- 1.72) ng x mL(-1), (154.53 +/- 12.38) ng x mL(-1) and (172.14 +/- 47.33) ng x mL(-1); AUC(last) were (29.38 +/- 3.69) ng xh x mL(-1), (148.43 +/- 72.85) ng x h x mL(-1) and (599.22 +/- 359.61) ng x h x mL(-1). The elimination of batroxobin was found to be in accord with linear kinetics characteristics. The results of pharmacodynamics showed that D-dimmer level increased significantly after the administration of batroxobin, which was similar with the changes of batroxobin plasma concentration. Simultaneously, Fib concentrations in Beagle dog blood decreased significantly after the iv administration of batroxobin, while recovered to base level after 48 hours. PT, TT and APTT significantly became longer after administration, which returned to normal level after 48 hours. Especially, the D-dimmer levels and the batroxobin concentration in plasma after intravenous infusion of the drug were synchronized in Beagle dogs. Changes between PD/PK results had obvious correlation, and the D-dimmer levels in plasma can be one of the important monitoring indicators of batroxobin in thrombolytic medication.

This paper is to report the study of the metabolism of forscolin in plasma and liver microsomes for guiding clinical therapy. Forscolin was quantified by HPLC-MS/MS. The metabolic stability of forscolin in rat, Beagle dog, monkey and human plasma and liver microsomes, mediated enzymes of forscolin and its inhibition on cytochrome P450 isoforms in human liver microsomes were studied. Results showed that forscolin was not metabolized in plasma of the four species but metabolized in liver microsomes of the four species. The t1/2 of forscolin in rat, Beagle dog, monkey and human liver microsomes were (52.0 +/- 15.0), (51.2 +/- 5.9), (6.0 +/- 0.2) and (11.9 +/- 1.8) min; CL(int) were (75.6 +/- 18.7), (60.9 +/- 6.8), (513.8 +/- 14.3) and (176.2 +/- 25.6) mL x min(-1) x kg(-1); CL were (34.8 +/- 4.5), (23.3 +/- 1.0), (40.3 +/- 0.5) and (17.9 +/- 0.3) mL x min(-1) x kg(-1), respectively. Forscolin was metabolized by CYP3A4 in human liver microsomes. There was definite inhibition on CYP3A4 at the concentrations of forscolin between 0.1 ng x mL(-1) and 5 microg x mL(-1). Therefore, forscolin is rapidly excreted from liver microsomes. Attention should be paid to the drug interaction when forscolin was used along with other drugs metabolized by CYP3A4 in clinics.

The purpose of this study was to investigate the effect of paclitaxel in combination with 20(s)-ginsenoside Rg3 on its anti-tumour effect in nude mice. In the Caco-2 transport assay, the apparent permeability from the apical side to the basal side (P(app)) (A-B) and P(app) (B-A) of paclitaxel were measured when co-incubated with different concentrations of 20(s)-ginsenoside Rg3. The results indicated that the penetration of paclitaxel through the Caco-2 monolayer from the apical side to the basal side was facilitated by 20(s)-ginsenoside Rg3 in a concentration-dependent manner. Meanwhile, 20(s)-ginsenoside Rg3 inhibited P-glycoprotein (P-gp), and the maximum inhibition was achieved at 80 µM (p0.05). The pharmacokinetic parameters of paclitaxel after oral co-administration of paclitaxel (40 mg/kg) with various doses of 20(s)-ginsenoside Rg3 in rats were investigated by an in vivo pharmacokinetic experiment. The results showed that the AUC of paclitaxel co-administered with 20(s)-ginsenoside Rg3 was significantly higher (p0.001 at 10 mg/kg) compared with the control. The relative bioavailability (RB) % of paclitaxel with 20(s)-ginsenoside Rg3 was 3.4-fold (10 mg/kg) higher than that of the control. The effect of paclitaxel orally co-administered with 20(s)-ginsenoside Rg3 against human tumour MCF-7 xenografts in nude mice was also evaluated. Paclitaxel (20 mg/kg) co-administered with 20(s)-ginsenoside Rg3 (10 mg/kg) exhibited an effective anti-tumour activity with the relative tumor growth rate (T/C) values of 39.36% (p0.05). The results showed that 20(s)-ginsenoside Rg3 enhanced the oral bioavailability of paclitaxel in rats and improved the anti-tumour activity in nude mice, indicating that oral co-administration of paclitaxel with 20(s)-ginsenoside Rg3 could provide an effective strategy in addition to the established i.v. route.

This paper is to report the study of the metabolism of lidamycin in vitro including in plasma and microsomes to guide clinical therapy. Lidamycin was quantified by detecting its active ingredient using HPLC-MS/MS. The metabolic stability of lidamycin in rat, Beagle dog, monkey and human plasma and liver microsomes, and its inhibition to cytochrome P450 isoforms in human liver microsomes were studied. Results showed that lidamycin was metabolized in the four species of plasma, and the sequence of metabolic rates in plasma were in ratin dogin humanin monkey. But among the four species of liver microsomes, lidamycin was metabolized only in monkey liver microsomes. There was almost no inhibition to cytochrome P450 isoforms at the concentrations of between 0.0005 and 10 ng x mL(-1). Therefore, the property of lidamycin metabolism in human is similar with that in dog, and metabolism of other drugs would not be decreased by cytochrome P450 as used along with lidamycin in clinic.

The paper is to report the pharmacokinetic character of a series of chemical compounds in vitro and in vivo. Metabolism stability of a series of chemical compounds was screened by using rat liver microsomes. The samples of different chemical compounds were combined and then simultaneously detected by LC-MS/MS. Compounds y13, y12 and y11 were screened out by microstability assay in vitro. The pharmacokinetics of compounds y11, y12 and y13 was evaluated by using SD rat. The plasma samples were pooled at the same time. The plasma concentrations were determined by LC-MS/MS. The pharmacokinetic character of two compounds y13, y11 was good by screening in vivo, so they were developed for further research. High-throughput screening of drug candidates in vitro and in vivo was effective, to provide information for the chemical structure information and lower the drug development risk.

To study the pathological basis of radiological reaction types of radiation-induced liver disease on multiphasic CT scans.Three pigs (tagged with A, B, and C) were subjected to single-dose radiation of 40, 40 and 30 Gy on the right or left lobe of the liver, respectively. At 42, 56, 133, and 168 days after irradiation, all pigs were examined with non-enhanced scan and contrast-enhanced scans at different time points after contrast injection. Hounsfield units (HU) were measured in each CT study to evaluate the density of irradiated and non-irradiated liver tissue to determine the reaction type. Liver tissues in the irradiation area obtained by needle biopsy with CT guidance were examined with electron microscopy, and specimens of the tissue corresponding to the region of interest on CT were obtained from necropsies for pathological examination.Radiologically, the 3 pig models presented with 3 reaction types on the multiphasic CT scans on days 133, 56, and 168 after radiation, respectively. Type 1 presented constant low-density change in all phases, the pathological basis of which was radiation hepatitis; type 2 showed pre-contrast phase isodense, arterial phase hyperdense, portal phase isodense and later phase hyperdense changes; type 3 was characterized by pre-contrast phase isodense, arterial phase hyperdense, portal phase hypodense and later phase hyperdense changes. The pathological basis of the last two radiological reaction types was radiation cirrhosis (postnecrotic cirrhosis).Different radiological reaction types of radiation liver injury on multiphase CT have different pathological basis, and multiphase contrast-enhanced CT may help distinguish the radiation reactions from tumor recurrence.