[Effects of isovitexin on transient outward potassium current of ventricular myocytes in rats].

To investigate the effects of isovitexin Ⅳ on transient outward potassium current in rat ventricular myocytes. In this study, MTT assay was used to investigate the safe range of isovitexin. The results showed that the IC50 of the drug was in the range of 10-30 µmol•L⁻¹, and the drug concentration of 1-3 µmol•L⁻¹ for the patch clamp test was within the safe range. In addition, the single ventricular myocytes were obtained by single-enzymatic hydrolysis through aortic retrograde perfusion. The transient outward potassium current (Ito) of rat ventricular myocytes was guided and measured by whole-cell patch-clamp technique and the changes of current characteristics were recorded after isovite was applied. When the concentration of IV was less than 0.1 µmol•L⁻¹, there was no significant effect on Ito. However, with the increase in the concentration of IV (≥0.3 µmol•L⁻¹), the peak of Ito was decreased gradually, from (32.32±2.9) pA/pF to （25.83±4.3） pA/pF, 1 µmol•L⁻¹ IV and (19.51±3.5) pA/pF, 3 µmol•L⁻¹ IV respectively, with an inhibition effect in a concentration-dependent manner. In the range of 1-3 µmol•L⁻¹, IV down-regulated the I-V curve of Ito significantly. The activation curve showed that IV can enable the maximum half activation potential (V1/2) to move to the positive direction, and the V1/2 was increased from (19.59±1.6) mV to (22.81±1.7) mV and (28.86±1.4) mV at concentration of 1, 3 µmol•L⁻¹, meanwhile the activation curve moved to the right. However, the maximum half inactivating potential (V1/2) of the steady-state inactivation curve of Ito was significantly decreased from (－51.43±0.99) mV to (－61.81±1.3) mV with concentration of 1 µmol•L⁻¹ and (－71.50±1.4) mV with concentration of 3 µmol•L⁻¹. The inactivation time constant of recovery from inactivation (τ) was up-regulated significantly from (94.89±0.73) ms to (118.5±1.5) ms and (162.4±1.4) ms at concentration of 1, 3 µmol•L⁻¹ respectively. Meanwhile IV could enable the inactivation recovery curve to move to the right, which suggested that it can prolong the recovery time from inactivation of the transient outward potassium channel. In conclusion, isovitexin had a high inhibitory effect on Ito in rat ventricular myocytes.

Testing bisphenol A analogs in human urine by solid-phase extraction liquid chromatography and tandem quadrupole mass-spectrometry / 中国职业医学

OBJECTIVE: To develop a method for simultaneous detection of 4 kinds of bisphenol A analogs in human urine by high performance liquid chromatography and tandem quadrupole mass-spectrometry. METHODS: The urine samples were extracted by solid phase extraction( Bond Elut Plexa) after hydrolyzed using β-glucuronidase and sulfatase. The gradient elution was carried out with acetonitrile-water. The bisphenol A-d16 and tetrabromobisphenol A-d10 were used as internal standard substances to conduct the quantitative analysis using the combined mode of liquid chromatography-mass spectrometry and mass spectrometry with the negative electrospray ionization,and the multiple reaction monitoring scan mode. RESULTS: The linear range of all the 4 kinds of bisphenol A analogs( Bisphenol F, Bishpenol A,Tetrachlorobisphenol A and Tetrabromobisphenol A) in urine was found to be 0. 50-100. 00 μg / L, and the linear correlation coefficients were 0. 998 6,0. 999 1,0. 999 6 and 0. 999 7,respectively. The limits of detection were 0. 21,0. 25,0. 01 and 0. 14 μg / L. The recovery rate was 69. 2%-99. 9%. The relative standard deviations of within-run and between-run precisions were 5. 5%-22. 8% and 2. 4%-14. 4%,respectively. The samples could be kept for at least 7 days at room temperature. The method was applied to detect urine samples of 38 children and 20 medical workers and the results were statistically analyzed. The detection rates of bisphenol A, bisphenol F, tetrachlorobisphenol A and tetrabromobisphenol A for children group were 94. 7%,94. 7%,0. 0% and 34. 2%,respectively,and those of the medical workers group were 100. 0%,100. 0%,5. 0% and 75. 0%,respectively. CONCLUSION: The method is effective for the detection of 4 kinds of bisphenol A analogs in human urine with simple operation,high sensitivity and good selectivity.

Impact of sirolimus and tacrolimus on the tumor recurrence after liver transplantation due to HCC beyond milan criteria: randomized controlled clinical trial / 中华器官移植杂志

Objective To compare the impact of the sirolimus and tacrolimus on the tumor recurrence after liver transplantation due to HCC beyond Milan criteria.Method Sixty-one liver transplantation recipients due to HCC beyond Milan criteria,between Jan.2008 and Apri.2012,were randomized,with the informed consent,into two different immunosuppression groups: sirolimus group (n=30) and tacrolimus group (n=31).In tacrolimus group,tacrolimus was used as the basic immunosuppressant,methylprednisolone was discontinued within one month postoperatively,and mycophenolate mofetil was used within the dosage of 1.5 g/d accordingly.In sirolimus group,the immunosuppresive scheme was the same as that of the tacrolimus group within postoperative one month,and from that,tacrolimus was transferred to sirolimus.No antineoplastic agents were given before tumor recurrence.The tumor recurrence rate and the survival rate of the recipients were compared between the two groups.Result The median follow-up duration was 35.2 months (10.3～ 60.2).The tumor recurrence rate at postoperative year 1,2,3 and 4 in the sirolimus group (13.3％,36.7％,43.3％ and 53.3％) was significantly lower than that in the tacrolimus group (38.7％,67.7％,74.2％ and 77.4％),P ＜ 0.05 for all.The one-year survival rate in the recipients postoperation had no significant difference between sirolimus group and tacrolimus group (90.0％ vs.87.1％,P=0.438).The 2-,3-and 4-year survival rate in the recipients was significantly higher in the sirolimus group (53.3％,33.3％ and 20.0％) than that in the tacrolimus group (41.9％,22.6％ and 9.7％),P ＜ 0.05 for all.The liver function and renal function of the recipients at the postoperative year 1,2,3 and 4 showed no significant difference between the two groups,P＞0.05.Conclusion In comparison with tacrolimus,sirolimus could significantly reduce the tumor recurrence rate and increase the survival rate for the liver transplant recipients due to HCC beyond Milan criteria.

Simultaneous determination of melamine and cyanuric acid residues in water and urine by solid phase extraction-hydrophilic interaction liquid chromatography-electrospray tandem mass spectrometry method / 中华预防医学杂志

<p><b>OBJECTIVE</b>We aimed to establish a sensitive quantified method for the simultaneous determination of melamine and cyanuric acid residues in water and urine by hydrophilic interaction liquid chromatography coupled with electrospray tandem mass spectrometry (HILIC-ESI-MS/MS) with the pretreatment of hydrophilic functional silica gel and cation exchange resin mixed solid phase extraction column(MCT), and to investigate the melamine and cyanuric acid residues in 501 water and 216 urine from several province and city.</p><p><b>METHODS</b>About 100 ml water (or 10 ml urine) was adjusted to pH 3.0 with concentrated hydrochloric acid, and then mixed with the internal standard solution((15)N3-melamine and (15)N3-(13)C3 -cyanuric acid) and 100 ml acetonitrile (10 ml for urine). The solution was cleaned with MCT solid-phase extraction column, and eluted once by 3 ml methanol and twice by 2.5 ml methanol (containing 5% ammonia water). The effluent was collected and dried by N2 flow at 40 °C, and then diluted to 2 mmol/L ammonium acetate containing 90% volume fraction acetonitrile. The completely dissolved solution was then filtered with 0.22 µm organic membrane; and the filtrate was detected by high performance liquid chromatography-tandem mass spectrometry and quantified with internal standards. The repeatability and sensitivity of the assay were evaluated. Then we detected the melamine and cyanuric acid residues in 501 water and 216 urine samples collected from several province and city.</p><p><b>RESULTS</b>By the quantification of internal standard (15)N3-melamine and (15)N3-(13)C3-cyanuric acid, the melamine and cyanuric acid were linear in the range of 2.0-1000.0 µg/L with correlation coefficient of 0.9998 and 0.9997. The detection limits of the method were separately 0.4 ng/L (melamine) and 0.3 ng/L (cyanuric acid) for water, and 4.0 ng/L (melamine) and 3.0 ng/L (cyanuric acid) for urine. The average recovery rate was around 95.3%-100.1% with the relative standard deviation (RSD) was <4.02%. Out of the 501 water samples, melamine was detected out in 19.9% (100/501) and cyanuric acid was detected out in 5.2% (26/501). The content was around 0.03-5.00 g/L. Melamine or cyanuric acid was detected out in 24.5% of the urine samples (53/216), with the content around 0.01-1.00 g/L.</p><p><b>CONCLUSION</b>The established method of solid phase extraction-hydrophilic interaction liquid chromatography-electrospray tandem mass spectrometry can satisfy the requirement for detection of melamine and cyanuric acid residues in all sorts of water and urine. Meanwhile, the two substances widely existed in water and Chinese population.</p>

Comparative research in two types of blood glucose monitoring methods after liver transplantation / 中国实用护理杂志

Objective To compare the significance of two blood glucose monitoring methods of eight-point and five-point after liver transplantation. Methods 160 patients after liver transplantation selected eight-point or five-point blood glucose monitoring methods randomly,each method had 80 patients.Blood glucose value one month after operation,incidence of hypoglycemia,hospitalization time,daily use of insulin,time needed to reach standard level,incidence of infection were compared. Results Eight-point and five-point blood glucose monitoring methods showed no difference in incidence of hypoglycemia,hospitalization time,daily use of insulin,time needed to reach standard level,incidence of infection.Rate of blood glucose to reach standard level 4 days,1,2,3,4 weeks after operation also showed no difference. Conclusions Comparison of eight-point and five-point blood glucose monitoring methods supply the information needed in clinic,reduce the burden of patients,strengthen the compliance of patients,it has important practical significance for clinical work.

Genotype analysis of enterovirus type 71 detected from patients with hand-foot-mouth disease in Shenzhen / 中华流行病学杂志

<p><b>OBJECTIVE</b>To carry out genotype analysis of enterovirus type 71, detected from hand-foot-mouth disease patients in Shenzhen in 2004.</p><p><b>METHODS</b>All samples were tested by reverse transcription-polymerase chain reaction (RT-PCR) using EV71 specific primer. The VP1 and VP4 of EV71 were cloned and sequenced. A phylogenetic tree was constructed by comparing the sequences with genogroups A, B and C genotypes using TreeView and PHYLIP software (3.6b).</p><p><b>RESULTS</b>The VP1 nucleotide sequence of 4 strains isolated from Shenzhen shared 87.8% - 92.0% identity with genogroup C, while the homogeneity of the VP4 nucleotide sequence was between 85.9% - 87.4%. The homogeneity of the VP1 nucleotide sequence with genotypes A and B was between 81.9% - 84.2% and was 80.6% - 85.0% with VP4. Among the 4 strains, the homogeneity of the VP1 nucleotide sequence was between 94.1% - 99.8% and was 100% with VP4 which formed a small group and could denominate EV71 genetype C4.</p><p><b>CONCLUSION</b>Similar results were obtained from phylogenetic analysis of EV71 based on VP1 and VP4 nucleotide sequence. The four EV71 strains causing epidemic in Shenzhen could be named as C4 subgroups.</p>

Risk Factors of Incision Infection after Liver Transplantation / 中华医院感染学杂志

OBJECTIVE To study and find reasonable methods of nursing care of incision through analyzing the risk factors in liver transplant patients.METHODS A total of 416 liver transplantation operations in our hospital from Sep 2004 to May 2006 were evaluated.The risk factors that resulted in the incision infection were considered.RESULTS The incision infection rate was decreased from 13.9% to 4.3% after improvement.CONCLUSIONS Nursing care is of great significance in preventing the incision infection in liver transplant patients.