BACKGROUND:Proliferation, migration and phenotypic changes of vascular smooth muscle cells is the core of the occurrence of atherosclerosis, and a series of related genes via methylation are involved in the process.
OBJECTIVE:To investigate the effects of oxidized low density lipoprotein (ox-LDL) on DNA methylation in the promoter region of the p21 gene and its potential mechanism in the pathogenesis of atherosclerosis.
METHODCultured human vascular smooth muscle cells were treated with different concentrations of ox-LDL (0, 10, 20, 40 mg/L) for 24 hours. The degree of DNA methylation was assayed by methylation-specific polymerase chain reaction, the expression of p21 mRNA was measured by reverse transcriptional polymerase chain reaction and the proliferative activity of vascular smooth muscle cells was determined by the MTT assay.
RESULTS AND CONCLUSION:The ox-LDL treatment resulted in a promotion in the methylation in the promoter region of the p21 gene and a decrease in mRNA expression with a concentration-dependent manner;it also induced a dose-dependent promoting effect on vascular smooth muscle cellproliferation. The atherogenic mechanism of ox-LDL might promote vascular smooth muscle cellproliferation by the hypermethylation of the p21 gene that may lead to the occurrence and development of atherosclerosis.

Objective:To improve and optimize the determination methods for 15 chemical sun-screening agents in cosmetics by HPLC described in Hygienic Standard for Cosmetics (2007 edition) to enhance the quality control of limited chemical sun-screening a-gents in cosmetics. Methods:The samples were extracted using the improved mixed liquor. The detection was performed on an Accur-asilC18(250mm×4.6mm,5um)analyticalcolumn,themobilephasewasmethanol-tetrahydrofuran-water(adjustingpHto2.60 with acetic acid) with gradient elution, the flow rate was 1. 0 ml·min-1 , the column temperature was 25℃,and the detection wave-length was 311nm. Results:The method showed good linear relationship and the correlation coefficient was above 0. 999 5, the detec-tion limit was 1. 9-18. 7 ng, and the average recovery was within the range of 97. 5%-113. 7% with RSD of 0. 85%-1. 56%(n=9). Conclusion:The improved method is reliable, which is the effective optimization and complement for the determination methods of chemical sun-screening agents in cosmetic described in Hygienic Standard for Cosmetics (2007 edition).

Objective To evaluate the outcomes of laparoscopic live donor nephrectomy via retroperitoneal approach. Methods From December 2003 to June 2004,6 patients underwent laparoscopic live donor nephrectomy (younger brother to elder sister in 1 case,elder brother to younger brother in 1, younger sister to elder brother in 1,elder sister to younger brother in 1,father to son in 1,mother to son in 1).For tissue matching,1 case was mismatched of 0 locus,2,of 2 loci and 3,of 3 loci.The results of PRA and lymphocytotoxicity test were negative.The patient was placed in the lateral decubitus.With 3 trocars, the left kidney was dissected via retroperitoneal approach.The arteries and veins were cut off by endoscopic articulating linear cutter. The donor's left kidney was taken out through a 6-7 cm long incision between 2 trocars.Staplers on renal arteries and veins were cut off,and the donor kidney was perfused with liquid,and then was implanted at the right iliac fossa of the recipients.Triple immunosuppressant therapy was used to prevent rejection. Results Laparoscopic donor nephrectomy was successfully performed on all the 6 cases by retroperitoneal approach.The kidney transplantations using the donor live kidneys were also successful.Postoperatively,the mean urine volume was 5036 ml(range,3500-6500 ml) on the first day;the mean serum creatinine level was 598 ?mol/L on the first day and 129 ?mol/L at 1 month.Follow-up of 3-9 months showed that the renal function was normal and no rejection occurred. Conclusions Laparoscopic donor nephrectomy via retroperitoneal approach is safe,feasible,and less invasive to the donor; however,this technique needs skilled surgeons of laparoscopy and renal transplantation.

Objective To evaluate the technique and effect of laparoscopic live donor nephrectomy via retroperitoneal approach. Methods Thirty-two donors (15 males and 17 females) underwent laparoscopic donor nephrectomy at our institution. Twenty-nine left and 3 right procedures were performed. Under general anesthesia, all donors were placed in lateral decubitus. Three transretroperitoneal trocars were used through different ports. The first 12 mm port was placed 2 cm inferior to the edge of rib and 1 cm lateral to the edge of sarcospinous muscle. The second 10 mm port was about 8 to 10 cm anterior to the first, or on the anterior axillary line and 2 cm inferior to the edge of rib. The third 5 mm port was also on the anterior axillary line but 2 cm superior to the iliac crest. The surgeon created the retroperitoneal working space with a constructed catheter balloon device, and made the donor kidney and ureter dissociated. Renal arteries and veins were cut with endoscopic articulating linear stapler for the first 6 patients and then with Hemo-Lok, a plastic clip with a lock, for the others. Finally, the dissected donor kidney and ureter were taken out through an incision extended from the first trocar port. Results All the 32 donor grafts were dissected successfully. The duration of procedure was ranged from 60 to 180 min, and the volume of blood loss was from 20 to 200 ml. The range of warm ischemia time was 3 to 8 min, and 25 to 50 min of cold ischemia time. Short renal veins were found in 3 cases, 1 cm, 1.5 cm and 2 cm respectively. And one case of renal endoarterial injury occurred. On the day after transplantation, the urine volume of recipients was from 2800 to 10 100 ml. There was no delayed graft function found in recipients. Conclusion Laparoscopic donor nephrectomy via retroperitoneal approach is available and safe to renal transplantation with minimal invasion to donors. It can help to obtain donor grafts with higher quality, though skillful laparoscopic technique is demanded.

Objective To explore the operative approach, method,indication,and clinical feasibility of laparoscopic or retroperitoneoscopic treatment of ploycystic kidney.Methods The renal cyst unroofing(bilateral,9 cases;unilateral,4 cases) was performed under laparoscope(2 cases) or retroperitoneoscope(11 cases).The renal adipose capsule was dissected with a harmonic scalpel to fully visualize the whole kidney.According to preoperative positioning results,the cysts at all sizes were exposed.Then all visible cysts were unroofed or fenestrated with a margin 0.5 cm from the renal parenchyma.The cystic fluid was drawn out as much as possible.Results The operations were completed smoothly in the 13 cases.Pneumatothorax developed on the day of laparoscopic operation in 1 case,and then was cured by closed thoracic drainage.The operation time was 50～240 min(mean,139 min),and the blood loss was 10～200 ml(mean,58 ml).Patients began out-of-bed activities in 1～2 days after operation and were discharged from hospital at 3～10 days.The pathological findings were in accordance with changes of ploycystic kidney.Follow-up examinations were carried out for 1～30 months(mean,14.3 months).Back pain was relived in 8 out of 11 cases.In 3 patients with a high blood pressure,the systolic pressure was decreased by 16～19 mm Hg at 9 months after operation.Ten patients presented normal hepatic and renal functions,while the remaining 3 patients with preoperative increased creatinine levels of 194～301 ?mol/L had a drop by 20～40 ?mol/L.Conclusions Treatment of cyst unroofing under laparoscope or retroperitoneoscope is a safe and effective method in the treatment of ploycystic kidney,being worthy of clinical recommendation.

Objective To evaluate the safety and effectiveness of the Hem-o-lok in retroperitoneal laparoscopic nephrectomy.Methods A total of 178 patients underwent retroperitoneal laparoscopic nephrectomy from November 2003 to November 2006.The operation was performed through 3 lumbar ports.The renal artery and veins were blocked with the Hem-o-lok and then severed.The ureter was cut at the site near the iliac blood vessel.For living donor nephrectomy,the kidney was taken out and infused with 4℃ kidney preserving fluid immediately.Results The operation was successfully completed in all the 178 cases and there was no conversion to open surgery.No Hem-o-lok ligating clips became dislodged.The mean operation time was 100 min(60-200 min),and the mean blood loss was 95 ml(20-200 ml).Complications included renal vein injury in 1 patient and pancreatic tail injury in 1 patient.The mean length of postoperative hospital stay was 5 days(4-8 days).Pathological results showed renal clear cell carcinoma in 65 patients,renal cystadenocarcinoma in 3 patients,renal leiomyosarcoma in 1 patient,renal lymphoma in 1 patient,renal oncocytoma in 2 patients,renal hamartoma in 2 patients,ureteral transitional cell carcinoma in 12 patients,ureteral squamous cell carcinoma in 2 patients,renal pelvis transitional cell carcinoma in 31 patients,renal pelvis xanthogranuloma in 1 patient,renal tuberculosis in 4 patients,accessory kidney in 1 patient,renal calculus in 4 patients,nephrohydrosis in 4 patients,and renal abscess in 1 patient.A total of 136 patients were followed for 1-36 months(mean,25 months),involving 64 patients followed for

Objective To establish a model of renal artery and vein blockage and detect the real time change of ascorbic acid in the renal cortex in vivo.Methods Sixteen rabbits were randomly divided into experiment and control groups(8 in each).Under anesthesia,the left kidney and artery-vein were dissociated and a microdialysis probe was inserted into the renal cortex.After being balanced for 60 minutes,the change of ascorbic acid in the renal cortex was detected.Ischemia was achieved by clamping the renal pedicle for 60 minutes followed by reperfusion for another 60 minutes in the experiment group.While in the control,the same procedure was performed during a same time interval without clamping the renal pedicle.Microdialysis samples were collected before,during,and after the ischemia in the rabbits,and then ascorbic acid in the microdialysates were real-time measured by an electrochemical method.Results The concentrations of ascorbic acid in the microdialysates were(18.9?7.5)?mol/L,(24.8?11.3)?mol/L,and(23.3?8.9)?mol/L respectively before,during,and after the renal warm ischemia.In the experiment group,the concentration of ascorbic acid was increased rapidly by 31.2% (24.8-18.9)/18.9] following ischemia(P0.05).Conclusions Ascorbic acid is a sensitive indicator of renal ischemia/reperfusion.The level of ischemia in renal context can be monitored in real time by detecting the concentration of ascorbic acid in vivo using microdialysis-electrochemical method.The method can be used for the further studies on ischemia/reperfusion.

Objective To explore the techniques and efficacy of retroperitoneal laparoscopic operations in the treatment of renal cyst. Methods A total of 35 patients were operated on under general anesthesia. A water-filled balloon was used to dilate the retroperitoneal cavity. The renal cyst was exposed by identifying the psoas major muscle, peritoneal reflection, pillar of diaphragm and so on. All cyst walls were unroofed with ultrasonic scalpel 3～5 mm from the edge of renal parenchyma. Results With renal cysts removed, the operations were successfully accomplished in all the 35 patients. The operation time was 15～60 min (mean, 32 min). The intraoperative blood loss was 5～60 ml (mean, 35 ml). The postoperative hospital stay was 3～6 days. Pathological examinations reported benign lesions in 34 patients and suspected cystadenocarcinoma in 1 patient. All the 35 patients were followed for 1～22 months. No recurrence was found with exception of 1 case of remaining renal cyst 1.5 cm in diameter under B-ultrasonography at the first postoperative month. The patient with suspected adenocarcinoma had been followed for 1 year and no evidences of neoplasm or metastasis were detected on the chest roentgenogram and B-ultrasonography of the liver and the kidneys. Conclusions Retroperitoneal laparoscopic unroofing is a safe and effective procedure for renal cyst.

Objective To evaluate the feasibility and curative effects of retroperitoneal laparoscopic surgery for adrenal pheochromocytoma. Methods Clinical records of 9 cases of retroperitoneal laparoscopic adrenalectomy of pheochromocytoma from October 2002 to November 2004 were reviewed. Results The operations were successfully completed in all 9 cases without severe complications. A sudden rise of blood pressure with an amplitude over 30 mmHg appeared in 3 cases during the operation, which took a favorable turn after adjusting the surgical performance and blocking the central vein. The operation time was 90~210 min (mean, 150 min). The intraoperative blood loss was 30~150 ml (mean, 50 ml). Blood transfusion was required in no cases. The postoperative length of hospitalization was 4~9 days (mean, 5 days). Pathological examination revealed benign adrenal pheochromocytoma in all cases. Follow-up for 3~24 months (mean,11 months)in the 9 cases found symptom free and no recurrence by B-ultrasonography or CT scans. Conclusions Retroperitoneal laparoscopic surgery for adrenal pheochromocytoma is a feasible procedure which offers advantages of minimal invasion, short operation time, less blood loss, quick postoperative recovery, fewer complications and good curative effects, having a promising future.

Objective To observe the prokinetic effect of domperidone on colon and compare with that of mosapride and cisapride.Methods ① In viva experiment:forty rats were divided into control,domperidone,mosapride,and cisapride groups with 10 in each group.Stran gauges were planted both in proximal and distal colons and colonic motor activities were recoded in conscious rats.② In vitro experiment:the prokinetics effects of dopamine or dopamine combined with domperidone on the contraction of isolated rat colon strips were recorded by tone-transducers in the thermostatic muscle bath.Results In viva experiments:① in the interdigestive period of resting,activities of rhythimic phasic contraction were recoded in colon at conscious rats,and ② it had been showed that dornperidone significantly enhanced the contraction of colon in dose-dependent manner.Compared with control group,the mean contraction amplitude of proximal colon and distal colon increased by 84.61% ± 7.26% and 76.37 % ± 8.47% in domeridone group,respectively,which was higher than those in mosapride group (50.32%±8.16% and 45.13%±7.16%,respectively),but as same as those in cisapride group (92.55% ± 8.37% and 81.27% ± 9.95%,respectively).In vitro experiments:① perfusion of dopamin (40 mg/ml) could significantly decrease the contraction of isolated colon strip by 91.56% ± 10.24% in comparison with Krebs-Ringer solution,and ① domperidone could block the relaxant effect of dopamin on the isolated colon strip.Conclusions Domperidone can significantly enhance the colonic motor activities via antidopaminergic action.The effects of domperidone are similar as eisapride and greater than mosapride.