AIMTo study the protective effects of ramipril in combination with BQ-123 on myocardial ischemia/reperfusion (I/R) injury in vivo in anesthetized rats.

METHODSHealthy male Wistar rats were divided into 5 groups randomly and subjected to 30 min of myocardial ischemia followed by 120 min reperfusion. Ramipril, BQ-123 and their combination were given to rats respectively. To observe the protection of their combination against myocardial I/R injury. HR, MAP and the change of ST-segment were observed. Ventricular arrthymias were monitored. The activity of creatine kinase (CK) and lactate dehydrogenase (LDH) in plasma, the infarct size and morphologic change were examined.

RESULTSCompared with I/R group, the elevation of ST-segment was decreased. Onsets of VPC and VT were delayed, durations of VPC and VT were shortened, especially their combination. Incidences of VPC, VT and VF were decreased. Activity of plasma CK and LDH was decreased, especially their combination. IS, IS/AAR and the morphology of myocardium were improved, especially their combination.

CONCLUSIONRamipril, BQ-123 and combined using these two agents protected myocardium from I/R injury in vivo. The protective effects on delaying onset of VA, shortening duration of VA, decreasing the activities of CK and LDH, decreasing infrarct size and improving morphology of myocardium were better than using ramipril and BQ-123 alone.

Animals ; Arrhythmias, Cardiac ; prevention & control ; Cardiotonic Agents ; pharmacology ; Creatine Kinase ; blood ; Drug Synergism ; L-Lactate Dehydrogenase ; blood ; Male ; Myocardial Reperfusion Injury ; prevention & control ; Peptides, Cyclic ; pharmacology ; Ramipril ; pharmacology ; Rats ; Rats, Wistar

OBJECTIVETo study the role of serum 25-hydroxyvitamin D in the early diagnosis of vitamin D deficiency rickets.

METHODSConcentrations of serum 25(OH)D, calcium, phosphorus and alkaline phosphatase were measured in normal control (n=73), suspected rickets (n=45) and confirmed rickets groups (n=65). Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of serum 25(OH)D for rickets.

RESULTSSerum 25(OH)D levels in the suspected and confirmed rickets groups were 83±30 and 72±31 nmol/L respectively, which was lower than in the normal control group (112±37 nmol/L) (P<0.01). There was no significant difference between the suspected and confirmed rickets groups (P>0.05). Vitamin D deficiency rates in the suspected and confirmed rickets groups were higher than in the control group (P<0.01). The ROC curve area of serum 25(OH)D for the diagnosis of rickets was 0.760 (95%CI 0.692-0.820, P<0.01), and the optimal operating point was 90.70 nmol/L (sensitivity 68.49%, specificity 72.73%). There was no significant difference in levels of calcium, phosphorus and alkaline phosphatase between the three groups (P>0.05).

CONCLUSIONSSerum 25(OH)D levels in infants with suspected and confirmed rickets are significantly reduced and this may reflect vitamin D deficiency . Therefore, it may be useful to check serum 25(OH)D levels in screening for rickets.

Female ; Humans ; Infant ; Male ; ROC Curve ; Rickets ; blood ; diagnosis ; Vitamin D ; analogs & derivatives ; blood

Recombinant humanized anti-ricin monoclonal antibody (MIL50) is a recombinant humanized monoclonal antibody targeting ricin. In this study, an ELISA method was used to establish a method for the determination of MIL50 in macaque serum, and a cross design method was used. Twelve rhesus monkeys were intravenously injected 1 mg·kg^-1 test preparation (MIL50 freeze-died powder injection) and reference preparation (MIL50 liquid preparation) to determine the plasma concentration of MIL50 at different time points, and the pharmacokinetic parameters were analyzed to compare the pharmacokinetic characteristics of MIL50 liquid preparation and freeze-died powder injection in rhesus monkeys. Animal welfare and experimental procedures follow the regulations of the Animal Ethics Committee of the Chinese Academy of Medical Sciences and Use of Laboratory Animals and the regulations derived by the Animal Care and Welfare Committee of the Institute of Radiation Medicine, Academy of Military Medical Sciences (IACUC-DWZX-2020-503). The results showed that there was no significant difference between C_max and AUC_0-5d in the two groups. The liquid preparation was the reference preparation, with C_max ratio of 101.6% and AUC_0-5d ratio of 101.9%, the 90% confidence interval of C_max was 79.42%-129.92%, and the 90% confidence interval of AUC_0-5d was 85.72%-121.18%. These results suggested that different dosage forms of MIL50 had certain differences in the changes of blood drug concentration in rhesus monkeys.

Nicotinamide adenine dinucleotide phosphate oxidases (NOXs) are the major enzymatic source of reactive oxygen species (ROS). NOX2 and NOX4 are expressed in the heart but its role in hypoxia-induced atrial natriuretic peptide (ANP) secretion is unclear. This study investigated the effect of NOX on ANP secretion induced by hypoxia in isolated beating rat atria. The results showed that hypoxia significantly upregulated NOX4 but not NOX2 expression, which was completely abolished by endothelin-1 (ET-1) type A and B receptor antagonists BQ123 (0.3 µM) and BQ788 (0.3 µM). ET-1-upregulated NOX4 expression was also blocked by antagonists of secreted phospholipase A2 (sPLA2; varespladib, 5.0 µM) and cytosolic PLA2 (cPLA2; CAY10650, 120.0 nM), and ET-1-induced cPLA2 expression was inhibited by varespladib under normoxia. Moreover, hypoxia-increased ANP secretion was evidently attenuated by the NOX4 antagonist GLX351322 (35.0 µM) and inhibitor of ROS N-Acetyl-D-cysteine (NAC, 15.0 mM), and hypoxia-increased production of ROS was blocked by GLX351322. In addition, hypoxia markedly upregulated Src expression, which was blocked by ET receptors, NOX4, and ROS antagonists. ET-1-increased Src expression was also inhibited by NAC under normoxia. Furthermore, hypoxiaactivated extracellular signal-regulated kinase 1/2 (ERK1/2) and protein kinase B (Akt) were completely abolished by Src inhibitor 1 (1.0 µM), and hypoxia-increased GATA4 was inhibited by the ERK1/2 and Akt antagonists PD98059 (10.0 µM) and LY294002 (10.0 µM), respectively. However, hypoxia-induced ANP secretion was substantially inhibited by Src inhibitor. These results indicate that NOX4/Src modulated by ET-1 regulates ANP secretion by activating ERK1/2 and Akt/GATA4 signaling in isolated beating rat hypoxic atria.

Nicotinamide adenine dinucleotide phosphate oxidases (NOXs) are the major enzymatic source of reactive oxygen species (ROS). NOX2 and NOX4 are expressed in the heart but its role in hypoxia-induced atrial natriuretic peptide (ANP) secretion is unclear. This study investigated the effect of NOX on ANP secretion induced by hypoxia in isolated beating rat atria. The results showed that hypoxia significantly upregulated NOX4 but not NOX2 expression, which was completely abolished by endothelin-1 (ET-1) type A and B receptor antagonists BQ123 (0.3 µM) and BQ788 (0.3 µM). ET-1-upregulated NOX4 expression was also blocked by antagonists of secreted phospholipase A2 (sPLA2; varespladib, 5.0 µM) and cytosolic PLA2 (cPLA2; CAY10650, 120.0 nM), and ET-1-induced cPLA2 expression was inhibited by varespladib under normoxia. Moreover, hypoxia-increased ANP secretion was evidently attenuated by the NOX4 antagonist GLX351322 (35.0 µM) and inhibitor of ROS N-Acetyl-D-cysteine (NAC, 15.0 mM), and hypoxia-increased production of ROS was blocked by GLX351322. In addition, hypoxia markedly upregulated Src expression, which was blocked by ET receptors, NOX4, and ROS antagonists. ET-1-increased Src expression was also inhibited by NAC under normoxia. Furthermore, hypoxiaactivated extracellular signal-regulated kinase 1/2 (ERK1/2) and protein kinase B (Akt) were completely abolished by Src inhibitor 1 (1.0 µM), and hypoxia-increased GATA4 was inhibited by the ERK1/2 and Akt antagonists PD98059 (10.0 µM) and LY294002 (10.0 µM), respectively. However, hypoxia-induced ANP secretion was substantially inhibited by Src inhibitor. These results indicate that NOX4/Src modulated by ET-1 regulates ANP secretion by activating ERK1/2 and Akt/GATA4 signaling in isolated beating rat hypoxic atria.

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.
Animals ; Area Under Curve ; Batroxobin ; administration & dosage ; blood ; pharmacokinetics ; pharmacology ; Dogs ; Enzyme-Linked Immunosorbent Assay ; Fibrin Fibrinogen Degradation Products ; metabolism ; Fibrinogen ; metabolism ; Fibrinolytic Agents ; administration & dosage ; blood ; pharmacokinetics ; pharmacology ; Infusions, Intravenous ; Male ; Partial Thromboplastin Time ; Prothrombin Time ; Thrombin Time

OBJECTIVETo study the specific binding of the artificial clonal aryl hydrocarbon receptor translocator (ARNT) with the natural aryl hydrocarbon receptor (AhR) and the recolonization by polyclonal antibody. The dose-response relationship with tetrachlo-rodibenzo-dioxin (TCDD) was also studied to develop TCDD detection method and the binding degree related to dose response.

METHODS(1) The target genes including AhR-PAS, AhR-C and ARNT-PAS were amplified by RT-PCR by using the total RNA purified from the liver cells of C57BL/6J mice as templates to construct pGEX-5X1 recombinants. The recombinant plasmids were expressed in E. coli. (2) The rabbits were immuned by the clonal fusion proteins: AhR-PAS, AhR-C to prepare the polyclonal antibody. (3) The natural AhR from the hepatic cytosol of C57BL/6J mice was extracted. The artificial cloning expressed fusion protein:GST-ARNT-PAS and the natural AhR were incubated in different dose of TCDD. The quantity of the heterodimer through affinity adsorption and Western blots were measured.

RESULTS(1) The target proteins including AhR-PAS, AhR-C and ARNT-PAS were successfully cloned and expressed in E. coli. (2) The detection limit of polyclonal antibody AhR-PAS and AhR-C were 5 ng and 1 ng, respectively. (3) The total protein concentration prepared from the liver cells was 60.5 mg/ml. The artificial clonal protein ARNT-PAS could specifically bind to the natural AhR complex with the existence of TCDD. The detection limit of TCDD was 0.25 pmol which was 80 pg approximately.

CONCLUSIONA TCDD detection method based on the aryl hydrocarbon receptor system was established and the detection limit might reach pg grade.

Animals ; Cells, Cultured ; Limit of Detection ; Liver Extracts ; chemistry ; Mice ; Mice, Inbred C57BL ; Polychlorinated Dibenzodioxins ; analysis ; Rabbits ; Receptors, Aryl Hydrocarbon ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

AIM: To investigate whether inactivation of extracellular signal-regulated kinase 1/2 ( Erk1/2 ) will affect the function of fibroblast growth factor 21 (FGF21) to regulate glucose and lipid metabolism .METHODS:Male db/db mice (8 weeks old) were treated with U0126 (an inhibitor of Erk1/2 kinase) for 1 week, and then treated with re-combinant human FGF21 protein and adenovirus-mediated FGF21 (Ad-FGF21).The profile changes of blood glucose and blood lipid were evaluated at 120 min or 4 weeks after FGF21 administration.Meanwhile, the molecular mechanism was ex-plored by in vitro study.RESULTS: Treatment of db/db mice with recombinant human FGF21 protein significantly re-duced blood glucose and triglyceride levels at 120 min after FGF21 administration , but these changes were comparable in U0126-treated mice .Furthermore , abnormal glucose and triglyceride levels , and glucose and insulin tolerance were strong-ly improved in db/db mice as accompanied with decreasing body fat content after 4 weeks of ad-FGF21 administration .In-terestingly, treatment with or without U0126 did not influence these effects of FGF21.Mechanically, treatment with Ad-FGF21 significantly upregulated the protein levels of p-Erk1/2 and peroxisome proliferator-activated receptor γ( PPARγ) as well as the expression of adiponectin at mRNA and protein levels in adipose tissues .However , treatment with or without U0126 did not change the profiles .On the other hand , in vitro experiments also indicated that treatment of adipocytes with recombinant human FGF 21 protein significantly activated Erk 1/2 phosphorylation , and upregulated the expression levels of PPARγand adiponectin (P<0.05).However, pre-administration of U0126 did not affect the profiles.CONCLUSION:Pharmaceutical inactivation of Erk 1/2 by U0216 does not affect the biological function of FGF 21 to regulate blood glucose balance and improve abnormal blood lipids in vivo.

BACKGROUNDThe genotype of epidermal growth factor receptor (EGFR) is associated with tyrosine kinase inhibitor and effectiveness of therapy, but its role in cytotoxic chemotherapy is still unknown. Previous studies indicated that certain EGFR mutations were associated with response and progression free survival following platinum based chemotherapy. Our recent studies have identified that EGFR genotypes in the tumour tissues were not associated with response to the first-line chemotherapy in Chinese patients with advanced non-small cell lung cancer (NSCLC). In this study, we investigated associations of EGFR genotypes from plasma of patients with advanced NSCLC and response to first-line chemotherapy and prognosis.

METHODSWe enrolled 145 advanced NSCLC patients who had received first-line chemotherapy in our department. We examined plasma EGFR genotypes for these patients and associations of EGFR mutations with response to chemotherapy and clinical outcomes.

RESULTSThere were 54 patients with known EGFR mutations and 91 cases of wild types. No significant difference was detected in the response rate to first-line chemotherapy between mutation carriers and wild-type patients (37.0% vs. 31.9%). The median survival time and 1-, 2-year survival rates were higher in mutation carriers than wild-types (24 months vs. 18 months, 85.7% vs. 65.7% and 43.7% vs. 25.9%, P = 0.047). Clinical stage (IV vs. IIIb), response to the first-line chemotherapy (partial vs. no) and EGFR genotype were independent prognostic factors.

CONCLUSIONPlasma EGFR mutations in the Chinese patients with advanced NSCLC is not a predictor for the response to first-line chemotherapy, but an independent prognostic factor indicating longer survival.

Adult ; Aged ; Antineoplastic Agents ; therapeutic use ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; genetics ; Female ; Genotype ; Humans ; Male ; Middle Aged ; Plasmids ; genetics ; Receptor, Epidermal Growth Factor ; genetics ; Survival Rate

Objective To establish a quantitative analysis method for determining 99mTc-HYNIC-PEG4-E[PEG4-c(RGDfK)]2 (99mTc-3PRGD2,a radioactive tumor agent)byγcounter, and to investigate the distribution of 99mTc-3PRGD2 in mice bearing with lung carcinoma xenograft. Methods The mice were divided into 4 normal groups and one blocking peptide group(control group). The 99mTc-3PRGD2(8μg/kg)was injected to mice bearing with lung carcinoma xenograft through the tail intravenous administration. Tissues of the normal mice were taken at 0.5,1,2 and 4 h. The control group were treated by 3PRGD2 and 99mTc-3PRGD2. The control mice were injected with the 3PRGD2 saline solution(2.5 mg/ml,0.2 ml)at 0.5 h earlier before the injection of 99mTc-3PRGD2. The tu?mor and organ tissues of the control mice were taken at 2 h. The radioactivity was detected by Gamma Counter. Results The radioac?tivity of 99mTc-3PRGD2 detected was high in the tumor and very low in brain. In addition,high radioactivity in kidneys and bladder sug?gested that the drug excreted by renal. Conclusion The results proved that the blocking peptide can competitively inhibit the combi?nation of 99mTc-3PRGD2 and integrinαvβ3 receptors.