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An accurate and validated liquid chromatography method and a triple quadrupole mass spectrometry method were developed and validated to simultaneously evaluate the cytochrome P450 (CYP) enzymes in vivo using the co-administration of these probes. Phenacetin, losartan, metoprolol and midazolam were used as the probe substrates for rat CYP1A2, CYP2C11, CYP2D4 and CYP3A1 enzymes, respectively. The purpose of the study was to investigate the effect of apatinib on these cytochrome P450 enzymes in vivo with co-administration of these probes. Plasma samples were prepared by precipitating protein with acetonitrile. The analytes were separated using a reversed-phase BEH C18 column (2.1mm×100mm, 1.7μm, Waters, USA) maintained at 40°C. The mobile phase consisted of acetonitrile and water (containing 0.1% formic acid) with a gradient elution pumped at a flow rate of 0.4mL/min. The analytes were detected with positive electrospray ionization in multiple reaction monitoring (MRM) mode for target fragment ions m/z 180.05→109.94 for phenacetin, m/z 423.1→207.2 for losartan, m/z 268.12→115.8 for metoprolol, m/z 326.02→290.99 for midazolam and m/z 285.1→193.1 for diazepam (IS). Good linearity was achieved to quantify the concentration ranges of 10-2000ng/mL for phenacetin, 10-1000ng/mL for losartan, 10-1000ng/mL for metoprolol and 1-100ng/mL for midazolam in rat plasma. The mean recoveries of phenacetin, losartan, midazolam and metoprolol from the plasma exceeded 77.07%. The intra-run and inter-run assay precisions were both less than 8.9%. This method was successfully applied to evaluate the effects of apatinib on the cytochrome P450 enzymes in rats.

DNA-damaging agents have been reported to be associated with cardiovascular complications, however, the underlying mechanisms remain to be clarified. In the present study, the possible vascular effects of cisplatin was assessed by measuring its effects on the contractile function of thoracic aortic rings dissected from Sprague-Dawley (SD) rats. Contraction of the aortic ring was induced by 60 mM KCl or 10−6 M phenylephrine (PE) in an ex vivo perfusion system. Cisplatin (200 μM) counteracted KCl- and PE-induced contraction by 57.6 and 91.8%, respectively, in endothelium-intact aortic rings. Similar results were obtained in endothelium-denuded aortas. Electromicroscopy analysis revealed severe damage to blood vessel walls in vivo by cisplatin. In addition, cisplatin significantly inhibited adenosine triphosphate (ATP)-induced intracellular Ca2+ concentration ([Ca2+]i) increases in human umbilical vein endothelial cells (HUVECs). These results suggested that the DNA-damaging agent cisplatin can affect the contractile function of thoracic aortas. In addition, in accordance with its DNA-damaging properties, the cardiovascular toxicity of cisplatin may be the result of its direct cytotoxicity.

Pseudomonas aeruginosa produces multiple virulence factors that have been associated with quorum sensing. The aim of this study was to evaluate the prevalence of drug resistant profiles and quorum sensing related virulence factors. Pseudomonas aeruginosa were collected from different patients hospitalized in China, the isolates were tested for their susceptibility to different common antimicrobial drugs and detected QS-related virulence factors. We identified 170 isolates displaying impaired phenotypic activity, approximately 80 % of the isolates were found to exhibit the QS-dependent phenotypes, among them, 12 isolates were defective in AHLs production, and therefore considered QS-deficient strains. Resistance was most often observed to Cefazolin (81.2 %), followed by trimethoprim-sulfamethoxazole (73.5 %), ceftriaxone (62.4 %) and Cefotaxime, Levofloxacin, Ciprofloxacin (58.8 %), and to a lesser extent Meropenem (20.0 %), Cefepime (18.8 %), and Cefoperazone/sulbactam (2.4 %) The QS-deficient isolates that were negative for virulence factor production were generally less susceptible to the antimicrobials. The results showed a high incidences of antibiotic resistance and virulence properties in P. aeruginosa, and indicate that the clinical use of QS-inhibitory drugs that appear superior to conventional antimicrobials by not exerting any selective pressure on resistant strains.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Angiogenesis is reported to play a pivotal role in the occurrence, development and metastasis of HCC. The renin-angiotensin system (RAS) is involved in the regulation of angiogenesis. Here, based on the analysis of HCC datasets from Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA), we found that there was a negative correlation between the mRNA levels of angiotensin converting enzyme 2 (ACE2) and CD34. To explore the association of RAS with the progression from fibrosis to cirrhosis to HCC, liver specimens and serum samples were collected from patients with hepatic fibrosis, cirrhosis and HCC. Relative hepatic mRNA levels of CD34 and ACE2 were determined by real-time PCR, and the serum concentrations of Angiotensin II (Ang II), Ang (1-7) and vascular endothelial growth factor (VEGF) were detected by ELISA. We found that ACE2 mRNA was gradually decreased, while CD34 mRNA was progressively increased with the increasing grade of disease severity. Concentrations of Ang II, Ang (1-7) and VEGF were higher in the sera of patients than in that of healthy volunteers. These proteins' concentrations were also progressively increased with the increasing grade of disease severity. Moreover, a positive correlation was found between VEGF and Ang II or Ang (1-7), while negative correlation was observed between mRNA levels of CD34 and ACE2. More importantly, patients with higher level of ACE2 expression had longer survival time than those with lower level of ACE2 expression. Taken together, our data suggests that the low expression of ACE2 may be a useful indicator of poor prognosis in HCC. The RAS may have a role in the progression of HCC.

A new intraoperative cisplatin administration method for patients with locally advanced gastric cancer (AGC) and without peritoneal metastasis, fibrin-sealant-delivered cisplatin chemotherapy, was reported, and its safety, pharmacokinetics, and efficacy were compared with cisplatin hyperthermic intraperitoneal perfusion chemotherapy. Forty-two AGC patients were randomly divided into 2 groups: fibrin-sealant-delivered cisplatin chemotherapy (FS) (n = 21) and cisplatin hyperthermic intraperitoneal perfusion chemotherapy (CHIC) (n = 21). Both groups received 120 mg cisplatin after complete cytoreductive surgery. At different time points, cisplatin concentrations in patients’ sera and urine samples were measured to determine time-dependent maximal concentration (Cmax) and the area under the curve (AUC). The primary and secondary end-points were overall survival (OS) and safety profiling, respectively. Occurrence of grade-3 to grade-4 liver or kidney dysfunction was less frequent in the FS group than in the CHIC group (28.6 % vs 47.6 %). Cisplatin Cmax and AUC for the serum and urine of the FS patients were significantly lower than that of the CHIC patients. Elimination half-life of cisplatin in the FS group was significantly longer than in the CHIC group (24.1 h vs 14.2 h). After a median follow-up of 40 months, 1-, 2-, and 3-years OS were 90.5 %, 71.4 %, and 61.9 % in the FS group, and 61.9 %, 47.6 %, and 42.8 % in the CHIC group, respectively. The median OS was 35.9 months in the FS group and 29.1 months in the CHIC group. Fibrin-sealant-delivered cisplatin chemotherapy was as effective and had a favorable pharmacokinetic profile with similar survival outcomes as cisplatin hyperthermic intraperitoneal perfusion chemotherapy following complete cytoreductive surgery of locally advanced GC without peritoneal metastases.

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) were developed for the treatment of benign lesions and early superficial esophageal cancers in the gastrointestinal (GI) tract. However, esophageal strictures frequently develop in patients who undergo EMR/ESD. Therefore, we aimed to investigate the clinical value of preventive balloon dilatation (BD) for esophageal diseases following endoscopic therapy. A total of 30 patients who had received EMR or ESD were enrolled in the study. Preventive BD was carried out for 12 cases within 1 week following EMR/ESD. The remaining 18 cases were not subjected to preventive BD and were used as an historic control. The results revealed that no complications, including esophageal stenosis and dysphagia, were observed in the patients who received preventive BD. In the control group, seven cases experienced dysphagia, of which two were released without clinical treatment and the other five were released following two or three BD procedures. The results indicate that preventive BD is an effective treatment for patients with esophageal diseases following EMR and should be considered at an early stage when the mucosal injury exceeds two-thirds of the esophageal lumen.

Cisplatin has been widely accepted as one of the most efficient anticancer drugs for decades. However, the mechanisms for the cytotoxic effects of cisplatin are still not fully understood. Cisplatin primarily targets DNA, resulting in the formation of DNA double strand breaks and eventually causing cell death. In this study, we applied two-dimensional electrophoresis coupled with LC-MS/MS to analyze the nuclear proteome of HeLa cells treated with cisplatin, in an effort to uncover new mechanistic clues regarding the cellular response to cisplatin. A total of 19 proteins were successfully identified, and these proteins are involved in a variety of basal metabolic and biological processes in cells, including biosynthesis, cell cycle, glycolysis and apoptosis. Six were related to the regulation of mRNA splicing, and we therefore asked whether the Fas gene might undergo alternative splicing following cisplatin treatment. This proved to be the case, as the splicing forms of Fas were modified in cisplatin-treated HeLa cells. This work provides novel information, from the perspective of the nuclear response, for understanding the cytotoxicity caused by cisplatin-induced DNA damage.