Objective To investigate the pharmacokinetics and relative bioavailability of praziquantel injection in buffaloes in contrast to praziquantel tablet. Methods A single oral administration of praziquantel tablet at a dose of 20 mg/kg or intramus-cular administration of praziquantel injection at a dose of 10 mg/kg was performed in six healthy adult buffalos according to a two-period crossover design. The praziquantel concentration in plasma was determined by a high performance liquid chromatography (HPLC)method. The pharmacokinetic parameters were calculated by non-compartmental analysis. Results The main pharma-cokinetic parameters of praziquantel tablet were as follows:Tmax=(0.60±0.29)h,Cmax=(0.57±0.37)μg/ml,T1/2β=(0.70±0.42) h,AUC=(0.80±0.70)(μg/ml)·h. The main pharmacokinetic parameters of praziquantel injection were as follows:Tmax=(0.65± 0.49)h,Cmax=(3.82 ± 1.17)μg/ml,T1/2β=(1.00 ± 0.73)h,AUC=(1.61 ± 0.89)(μg/ml)·h. The relative bioavailability of pra-ziquantel injection was 402.5％in contrast to praziquantel tablet. Conclusion The praziquantel injection has pharmacokinetic characteristics of rapid absorption,high bioavailability and extensive distribution,and the clinical recommended dosage of pra-ziquantel injection is 10 mg/kg.

Objective To evaluate the effect of hydrogen on mitochondrial fusion during myocardial ischemia-reperfusion (I/R) in aged rats.Methods One hundred and fifty pathogen-free healthy male Sprague-Dawley rats,aged 18 months old,weighing 400-500 g,were divided into 5 groups (n=30 each) using a random number table:control group (group C),sham operation group (group S),group I/R,normal saline group (group NS) and hydrogen-rich saline group (group H).Group C received no treatment.The anterior descending branch was only exposed but not ligated in group S.Myocardial I/R was induced by occlusion of the anterior descending branch of the left coronary artery for 30 rmin followed by reperfusion in I/R,NS and H groups.Hydrogen-rich saline 1 ml/100 g was injected intraperitoneally at 5 min before reperfusion in group H,while normal saline 1 ml/100 g was injected intraperitoneally at 5 min before reperfusion in group NS.The rats were sacrificed at 12 and 24 h of reperfusion,and hearts were removed for examination of the pathological changes and for determination of apoptosis in cardiomyocytes (by TUNEL) and expression of Mfn1 and Mfn2 protein and mRNA in myocardial tissues (by Western blot or real-time polymerase chain reaction).The apoptosis index was calculated.Results Compared with C and S groups,the apoptosis index of cardiomyocytes was significantly increased and the expression of Mfn1 and Mfn2 protein and mRNA in myocardial tissues was down-regulated at 12 and 24 h of reperfusion in I/R,NS and H groups (P＜0.05).Compared with NS and I/R groups,the apoptosis index of cardiomyocytes was significantly decreased and the expression of Mfn1 and Mfn2 protein and mRNA in myocardial tissues was up-regulated at 12 and 24 h of reperfusion in group H (P＜0.05).The pathological changes of myocardial tissues were significantly attenuated in group H when compared with group I/R.Conclusion The mechanism by which hydrogen attenuates myocardial I/R injury is related to promoting mitochondrial fusion and inhibiting apoptosis in cardiomyocytes of aged rats.

OBJECTIVETo identify the risk factors associated with lymph node metastasis in rectal cancer after neoadjuvant chemoradiotherapy (CRT).

METHODSFrom January 2005 to December 2013, the clinical data of 178 patients with advanced rectal cancer undergoing radical excision after neoadjuvant CRT in our department were reviewed retrospectively. A total of 11 clinicopathologic factors relating to lymph node metastasis were studied using univariate and multivariate Logistic regression analyses.

RESULTSThere were 74(41.6%) cases with lymph node metastasis, while 104 cases without lymph node metastasis. Univariate analysis showed that age(P=0.000 2), post-CRT CEA level(P=0.011 2), ypT stage(P=0.000 0), pathologic type(P=0.004 0), and tumor regression grade(TRG)(P=0.033 8) were significantly associated with lymph node metastasis. Multivariate analysis showed that age(OR=2.385, 95% CI:1.372 ~ 4.147, P=0.002 1), post-CRT CEA level(OR=2.310, 95% CI:1.005 ~ 5.307, P=0.048 6) and ypT stage(OR=2.592, 95% CI:1.236 ~ 5.432, P=0.011 7) were independent risk factors. However, 15.8% of the patients who achieved TRG1 had lymph node metastasis and TRG failed to independently correlate with lymph node metastasis in rectal cancer after neoadjuvant CRT.

CONCLUSIONSThere was a higher ratio of lymph node metastasis in rectal cancer patients who were young, CEA≥5 μg/L or deep invasion after neoadjuvant CRT. Therefore, neoadjuvant CRT should be carefully considered in these patients.

Age Factors ; Carcinoembryonic Antigen ; blood ; Chemoradiotherapy ; Female ; Humans ; Lymphatic Metastasis ; diagnosis ; Male ; Neoadjuvant Therapy ; Neoplasm Grading ; Neoplasm Invasiveness ; Rectal Neoplasms ; complications ; epidemiology ; therapy ; Remission Induction ; Retrospective Studies ; Risk Factors ; Treatment Outcome