AIM To elucidate the possible antiarrhythmic mechanism of matrine. METHODS Whole-cell patch-clamp technique was used to record ionic currents in ventricular myocytes. RESULTS In guinea pig ventricular myocytes, matrine 100 μmol·L-1 prolonged 90% action potential duration (APD90) by 40% at a stimulation of 0.1 Hz in a frequency-independent manner, inhibited IK1 by 47% at the test potential of -120 mV, reduced IKr,tail by 50% and had no effect on IKs,tail. CONCLUSION Matrine prolonged APD through blockade of multiple potassium currents, which may relate to its antiarrhythmic efficacy.

AIM: To observe the changes of iNOS and eNOS in lung tissue and NO in bronchoalveolar lavage fluid (BALF) in smoking rats. METHODS: 80 Wistar rats were divided into control, smoking group, L-NIL group and L-NAME group (rats were exposed to smoke and injected (i.p.) with selective iNOS inhibitor L-NIL or NOS inhibitor L-NAME). iNOS and eNOS protein levels in whole lung were detected by immunohistochemical staining, and NOS mRNA was quantified using RT-PCR. In addition, NO - 2/NO - 3 was determined using Griess assay. RESULTS: The expression of iNOS mRNA and protein in smoking rats increased, the expression of eNOS mRNA and eNOS protein decreased, and the total cell count and the level of NO - 2/NO - 3in BALF increased( P

Objective To explore the application of the evidence-based case report method in the standardization training of resident physicians in the department of endocrinology. Methods Fifty-one resi-dents recruited from the endocrinology department were randomly divided into the experiment group (26 cases) and control group (25 cases). The evidence-based case report method was conducted in the ex-peri-mental group, while the traditional clinical teaching mode was applied in the control group. The re-sults of the examination of two groups including the theoretical test and skill test were compared and the question-naire survey was conducted to find out the differences of students' interest in learning, clinical skills and satisfaction. All data were compared using t test. Results There was no significant difference in theoretical test between the two groups (P>0.05). The total score of the skill test in the experimental group was (85.13 ±4.63) and the control group was (76.79 ±3.11) (P=0.000). The students in the experimental group showed that the teaching method had more significant effects on improving their learning interest and initiative, clinical thinking ability, clinical work ability, literature review ability and medical article writing ability. Scores of satisfaction with teaching methods (total score was 10) for experimental group were (9.69 ±0.34), which was also significantly higher than those in the control group (8.01 ±0.39) (P=0.000). Conclusion The application of evidence-based case report teaching method in the standardized training of resident physicians in department of endocrinology is worthy of being perfected and further popularized in clinical teaching work.

Objective To analyze artifacts of gross tumor volume (GTV) and correlated factors in each phase images of four dimensional CT (4DCT) for peripheral lung cancer based on three dimensional CT (3DCT) assisted with active breathing control.Methods Nineteen patients with peripheral lung cancer underwent 3DCT (CTFB) and 4DCT simulation scans during free breathing and then underwent 3DCT simulation scans in end inspiration hold (CTEIH) and end expiration hold (CTEEH) assisted with active breathing control.The relative deviations (Devref) between the reference GTV (GTVref) and the GTVsdelineated based on CTFB (GTVFB) and all phases of 4DCT were calculated respectively.Correlations between GTVref and Devmax and between the tumor motion in the cranio-caudal (CC) direction and Devref were analyzed.Results The maximum median Devref of GTV was GTVFB with 17.83％,and the maximum median Devref of the GTV in all phases of 4DCT was GTV30 with 17.20％.A significant negative correlation was found between GTVEIH and Devmax (r =-0.691,P =0.001).The Devref was crrnelated with the tumor motion amplitude in the CC direction (r =0.323-0.617,P =0.005-0.150).The partial regression coefficient of influence of GTVref size and motion amplitude in the CC direction to the tumor Devmax were -0.500 and 0.583,P =0.002 and 0.001,respectively.Conclusions The GTV artifacts in different phase of 4DCT for the peripheral lung cancer were different to each other,and the influence of target displacement to artifacts was larger than that of target volume,so artifacts could be reduced by controlling breathing to reduce target displacement.

Objective To study the impacts of berberine on the growth, migration and radiosensitivity in human breast cancer cells.Methods MTT assay was used to evaluate cell growth.In vitro scratch migration assay was used to determine cell migration.Annexin V assay was used to detect cell apoptosis.The distribution of cell cycle was evaluated by flow cytometry assay.Colony formation assay was used to detect the influence of berberine on cell radiosensitivity. Western blot assay was employed to measure protein expression.Results Berberine inhibited cell growth and migration in two human breast cancer cell lines, MCF-7 and MDA-MB-231, in a dose-and time-dependent manner. Furthermore,berberine resulted in a cell cycle G0/G1 arrest.Compared with control,the early apoptosis in MDA-MB-231 and MCF-7 cells treated with 40 pμmol/L of berberine was as high as 86.6％ and 66.6％ (t =8.79,10.32,P ＜ 0.01 ),respectively. Berberine caused a dose-dependent increase in Bax and Caspase-3 protein expressions,but did not change Cyclin D1 protein expression,while suppressed the expressions of Cyclin B1 and Bcl-2 protein. As analyzed with multi-target click model fitting curves,the SERD0 of berberine-treated cells were 1.12 and 1.22 for MDA-MB-231 and MCF-7cells respectively at the dose D0 of X-rays.Conclusions The berberine inhibited the growth and migration of breast cancer cells via apoptosis induction and cell cycle arrest.Moreover,berberine increases cell sensitivity to X-ray irradiation.

Objective To assess the anti-arrhythmic activity and cardioprotective effects of Wenxin Granula, a traditional Chinese formula (consisting of Salviae Miltiorrhizae Radix, Polygonati Rhizoma, Notoginseng Radix et Rhizoma, Nardostachyos Radix et Rhizoma, Angelicae Sinensis Radix, and Succinum), on heart in ischemic-induced myocardial infarction (MI) rats and compare with those of Amiodarone which have been demonstrated in clinic. Methods Rats were randomly divided into Sham-operated (control), Ml + Amiodarone [5 mg/(kg·d)] (MI), and MI + Wenxin Granula [10 mg/(kg·d)] groups and left anterior descending coronary artery was occluded in each group. After left anterior descending for 12 h, standard lead Ⅱ of administration electrocardiogram was recorded in order to analyze the occurrence of arrhythmia. After one month, the size of the infarct area of heart was evaluated by TTC staining method and haemodynamic function was assessed to detect the heart function. Laser scanning confocal microscope and the technique of patch clamp were used to detect the intracellular Ca2+ ([Ca2+]j) and L-type calcium current (ICa-L), respectively. Results Both Wenxin Granula [10 mg/(kg·d)] and Amiodarone [5 mg/(kg·d)] could markedly decrease the incidence of arrhythmia in heart of rats which were subjected to ischemic injury. After one month, Wenxin Granula could significantly decrease mortality to 22.22% and reduce the infarct area (P < 0.05), but Amiodarone did not. The mechanism may involve that Wenxin Granula attenuated [Ca2+]j decreasing in MI rats. Additionally, Wenxin Granula could obviously ameliorate the impaired heart function of MI rats by decreasing the elevated left ventricular end-diastolic pressure and increasing the attenuated maximum change velocity of left ventricular pressure in the isovolumic contraction or relaxation period. On the other hand, electrophysiological experiment results revealed that Wenxin Granula administration one month later also increased the reduced ICa-L density in rat ventricular myocytes in MI rats. The results of LSCM showed that Wenxin Granula could recover the amplitude of [Ca2+]j decreased by heart failure during long term. Conclusion Wenxin Granula could not only inhibit the incidence of arrhythmia but also decrease the mortality, which was accompanied by recovering the amplitude of [Ca2+]j. This protective effect of Wenxin Granula may partially be mediated through changing ICa-L.as well as increasing [Ca2+]j.