Finite element analysis on stress distributions during novel semi-hip prosthesis assembly / 医用生物力学

Objective To simulate the stress generated by contact with the femur during the assembly of novel semi-hip prosthesis, and discuss the operating limits and adaptive prosthesis profile in clinic. Methods CT scans were conducted on the proximal end of the femur in a male volunteer of 60 years old as a physical model. By transferring the CT data to finite element modeling software, the physical model was simplified, meshed, materialized and assembled with the model of prosthesis to establish the three-dimensional finite element model. Surface to surface contact relationship between the femur and the prosthesis was also constructed by utilizing contact elements. Relative sliding distance and stress distribution were solved while simulating the process of assembling the prosthesis. Results Additional stress was generated on the sudden change area of the contact surface when the prosthesis was seated. The greatest contact pressure came from the changing section of the ridge of the prothesis, and the maximum assembly stress and sliding distance range increased nonlinearly along with the pushing distance. The increase rate of additional stress was enhanced significantly while Δz≥0.5 mm. Conclusions Compared with the prosthesis without ridge, the prosthesis with ridge can be easily seated and obtain mechanical stabilization. However, the relevant clinical operating limits should be obeyed to avoid generating excessive additional stress during the implantation of prosthesis, which may cause treatment failure due to the damage in bone cortex.

The application of uncut Roux-en-Y esophagojejunostomy with distal jejunal pouch on behalf of the stomach surgery in the digestive tract reconstruction after total gastrectomy / 中华外科杂志

<p><b>OBJECTIVE</b>To study the clinical value of uncut Roux-en-Y esophagojejunostomy with distal jejunal pouch on behalf of the stomach (URYAJP) surgery in the digestive tract reconstruction after total gastrectomy.</p><p><b>METHODS</b>A retrospective analysis of radical resection of the whole stomach in 486 cases of gastric cancer patients, divided into the URYAJP group (n = 189), the P-loop Roux-en-Y behalf of the stomach surgery (PRY) group (n = 150) and pure Roux-en-Y reconstruction (RY) group (n = 147). Three groups were compared in patients with surgical reconstruction time, the occurrence of postoperative complications, the postoperative weight after 6, 12 and 24 months, the single meal food intake and prognostic nutritional index (PNI) and Visick points class situation after 12 and 24 months.</p><p><b>RESULTS</b>(1) The URYAJP group and RY group had no significant difference in digestive tract reconstruction time ((37 ± 6) minutes and (38 ± 6) minutes respectively), but PRY group was significantly prolonged ((47 ± 6) minutes, t = 7.52 and 6.54, P < 0.05). (2) In the comparison of the incidence of complications, URYAJP group has 2.1% rate of Roux stay syndrome (RSS) incidence, significantly less than PRY group (21.3%) and RY group (19.7%) (χ² = 14.84, P < 0.05). (3) In the comparison the postoperative nutritional status, URYAJP group clear asset, showing the degree of ((3.1 ± 1.0) kg) weight loss after 12 months (t = 25.03 and 22.99, P < 0.05). And after 12, 24 months, a single meal eating reached the preoperative level is 94.8% and 96.9% in URYAJP group, while PRY group and RY group is less than 50% (χ(2) = 61.10, 69.17, 65.17 and 73.29, P < 0.05). URYAJP Group reach the preoperative levels of PNI in 24 months after surgery, while PRY and RY group were still lower than per-operation (t = 106.97 and 100.37, P < 0.05). (4) The Visick points class I-II postoperative 12 and 24 months in URYAJP group were 92.7% and 93.8%, significantly better than group B and C (χ² = 10.63, 14.19, 10.10 and 10.74, P < 0.05).</p><p><b>CONCLUSIONS</b>URYAJP surgery give full play to maintain intestinal continuity, simple operation, and advantages of food storage bags, it can reduce the long-term postoperative complications, improve the nutritional status of patients and improve quality of life. It is worthy of promoting a way of gastrointestinal reconstruction.</p>

Nutritional therapy of duodenocutaneous fistula / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To summarize the experience in nutritional support for the management of duodenocutaneous fistula.</p><p><b>METHODS</b>Data of 32 patients with duodenocutaneous fistula in Zhejiang provincial people's hospital from January 1999 to December 2009 were analyzed retrospectively.</p><p><b>RESULTS</b>The mean duration of nutritional support was 35.6 days (range, 8-82 days). Eight received total parenteral nutrition, 2 total enteral nutrition, and 22 parenteral nutrition combined with enteral nutrition respectively. Succus entericus reinfusion with enteral nutrition was used in 11 cases, glutamine-enriched nutritional support in 28 cases, somatostatin in 12 cases. In these patients, the healing rate was 75.0% after conservative treatment. In the 8 patients who underwent surgery, 6 were cured and 2 died (due to severe abdominal infection and multiple organ failure). A total of 30 patients had the fistulas cured and discharged.</p><p><b>CONCLUSIONS</b>Parenteral nutrition combined with enteral nutrition, succus entericus reinfusion combined with enteral nutrition, glutamine-enriched nutritional support and somatostatin are important factors for the healing of duodenocutaneous fistulas.</p>

Clinical study on the alimentary canal reconstruction of uncutted Roux-en-Y with jejunal pouch for total gastrectomy / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the efficacy of uncutted Roux-en-Y esophagojejunostomy with jejunal pouch (URYJP) after total gastrectomy.</p><p><b>METHODS</b>Total gastrectomy was performed on 168 patients of gastric cancer, and 3 methods were used for reconstruction: the uncutted Roux-en-Y esophagojejunostomy with a jejunal pouch was performed on 69 patients(group A),Roux-en-Y esophagojejunostomy with the P-type jejunal pouch on 50 patients(group B),and Roux-en-Y esophagojejunostomy with the Orr-type jejunal pouch on 49 patients (group C). The alimentary tract reconstruction time, morbidity and mortality were compared. The 121 cases that survived for more than 1 year were analyzed for quality of life(QOL),including body weight, intake quantity, prognosis nutritional index (PNI), and Visick scores 6 and 12 months after the operations.</p><p><b>RESULTS</b>All the patients recovered quickly and no anastomosis leakage or duodenal fistulas were found. It took (30+/-7) minutes to finish the reconstruction in group A, which was significantly shorter than that in group B [(57+/-6) minutes] or in group C [(48+/-6) minutes]. There were no significant differences among 3 groups in the incidence of alkaline reflux gastritis. The incidence of Roux stasis syndrome was 2.2% in group A, which was significantly lower than 17.9% and 19.4% in group B and C. Weight loss and food intake gain in group A was superior to those in group B and C 6 months and 12 months postoperatively. As compared with prognosis nutritional index(PNI) postoperatively, those of 3 groups decreased significantly 6 months postoperatively. At 12 months after operation, the PNI of group A returned to the level before operation, while PNI of both group B and C remained significantly lower than those before operation (both P < 0.05). The Visick score of group A was superior to those of group B and C 6 months and 12 months postoperatively.</p><p><b>CONCLUSIONS</b>The new uncutted Roux operation with jejunal pouch can prevent alkaline reflux gastritis and Roux-en-Y stasis syndrome. It may be a standard procedure for reconstruction after total gastrectomy.</p>

Expression of vascular endothelial growth factor C and survivin in gastric carcinoma and their clinical implications / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the expression of vascular endothelial growth factor C (VEGF-C) and survivin protein in human gastric carcinoma,and to evaluate their clinical implications.</p><p><b>METHODS</b>The expressions of VEGF-C and survivin protein in tumor tissues,matched para- tumor tissues from 97 cases with gastric cancer and normal tissues form 20 normal controls,were determined by immunohistochemistry. Their relationships with clinicopathological parameters were analyzed.</p><p><b>RESULTS</b>The positive rate of VEGF-C and survivin protein in tumor tissues (66.0% and 57.2%) was significantly higher than those in matched para-tumor tissues normal tissues (P< 0.05). There were no significant differences in VEGF-C expression considering tumor size,localization,histological grade,venous invasion,and distant metastasis (P > 0.05), while its expression was correlated with serosal infiltration, lymphatic invasion, lymph node metastasis and TNM stage III-IV (P< 0.05). The survivin expression was significantly related with serosal infiltration,lymphatic invasion, regional lymph node metastasis,distant metastasis, and TNM stage III- IV (P< 0.05), but not with histological grade, localization,venous invasion,and tumor size (P > 0.05). The 1, 3 and 5-year survival rates of the patients with positive VEGF-C or survivin protein were significantly lower than those of the patients with negative VEGF-C or survivin (P< 0.05), respectively. In additional,the expression of VEGF-C was positively correlated with survivin expression in gastric carcinoma (P< 0.01).</p><p><b>CONCLUSION</b>The expressions of VEGF-C and/or survivin may be indicators for poor prognosis of gastric carcinoma.</p>

Diagnosis and treatment of benign duodenal tumor / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the diagnosis and treatment of benign duodenal tumor.</p><p><b>METHODS</b>Clinical data of 14 patients with benign duodenal tumor confirmed pathologically or by operation from Oct.1988 to Oct.2001 were analyzed retrospectively.</p><p><b>RESULTS</b>Of 14 patients, 5 had Brunner's grand adenoma, 4 mesenchymoma, 2 leiomyoma, 2 hemangioma, 1 lipoma. Upper abdominal discomfort (64% ), gastrointestinal bleeding(50% ) and abdominal pain(20% ) were common manifestations. All cases received gastroscopy and only one case was diagnosed. Five cases received duodenoscope and the diagnosis was confirmed in 4 cases. Nine cases received hypotonic duodenography and lesions were found in 8 cases. Digital subtraction angiography was performed in 3 cases and detected all lesions. Computed tomographic scan and B-ultrasound were performed in 2 cases and only one case was diagnosed. Eleven cases (79% ) got definite diagnosis before operation. Tumor resection was performed in all patients. Perioperative death occurred in one patient. No recurrence occurred in 13 cases after following up from 2 to 11 years.</p><p><b>CONCLUSION</b>Upper abdominal discomfort and gastrointestinal bleeding are common features in patients with benign duodenal tumor. Duodenoscopy and hypotonic duodenography are good diagnostic approaches. Surgical tumor resection is the first choice of treatment.</p>

Evaluation of transabdominal modified Sugiura procedure / 中国普通外科杂志

Objective To evaluate the advantage of transabdominal modified Sugiura procedure Methods We retrospectively analyzed 45 cases undergoing transabdominal modified Sugiura procedure from May 1997 to May 2003 The procedure included devascularization of near half gastric and inferior part of esophagus after splenotomy The left and right vagus nerves, the anterior and posterior Latarjet nerves and paraesophageal collateral veins were left intact The gastric submucous vasculature was sutured on the plane 3～5 cm distal to cardia (suture group); or the esophagus 3 cm above cardia was cut and reanastomosed with pipe anastomat Results There was no inhospital mortality Free portal veinous pressure and portal vein flow speed did not change significantly The flow volume of portal vein decreased ( P

The change in metabolism of fatty acids in breast cancer cells and its significance / 肠外与肠内营养

Objectives:To observe the changes in metabolism of fatty acids in breast cancer cells and the effects of inhibiting fatty acid synthase(FAS) on the growth of breast cancer cells. Methods:By RT PCR,the expression of FAS mRNA in breast cancer cell line was examined.The growth inhibition of breast cancer cells by specific FAS inhibitor, cerulenin, was determined by MTT assay.Flow cytometric analysis was used to study the changes of cell cycle. Results:FAS mRNA expression in MCF 7 cells was high.We found that cerulenin caused dose and time dependent inhibition of growth of MCF 7 cells.The growth inhibition of MCF 7 after 48 hours exposure of cerulenin at 2.5,5,10 and 20 mg/L was ( 43.47 ?4.58)%,(62.92?2.68)%,(81.93?0.91)% and (67.7?12.27)%( P

The effects and the mechanisms of exogenous fatty acids on colorectal cancer cells / 肠外与肠内营养

Objectives: To observe the effects and the mechanisms of exogenous fatty acids on colorectal cancer cells(LoVo). Methods:The effect of exogenous fatty acids on LoVo cells was determined by 5 diphenyl tetrazolium bromide(MTT) assay.The content of MDA was examined to evaluate the extent of lipid peroxidation. Results:The growth of LoVo cells was inhibited by polyunsaturated fatty acids(PUFAs).The inhibitory effect of saturated fatty acids and monounsaturated fatty acids on LoVo cells was not showed.None of the fatty acids was found to fibroblast cells(HLF).PUFAs caused the significant rising of intracellular MDA content. Conclusions:PUFAs could inhibit the growth of colorectal cancer cells.The strengthening of lipid peroxidation may be one of the mechanisms.

Surgical modality of superior mesenteric artery syndrome: experience of 21 cases / 中国普通外科杂志

Objective To explore the cause of and treatment for superior mesenteric artery syndrome (SMAS). Methods Clinical data of 21 patients from 1992 to 2002 with SMAS were analyzed retrospectively. Results Three cases of SMAS recovered with nonoperative treatments, eighteen recovered after surgical therapy including lysis and downward movement of the ligament of Treitz and extensive mobilization of the duodenum in 4 cases (Type Ⅰ), lysis and Roux-en-Y duodenojejunostomy in 9 cases (Type Ⅱ), side to side duodenojejunostomy in one (Type Ⅲ), and Billroth-Ⅱ gastrectomy in 2 cases (Type Ⅳ), and anterior side to side duodenojejunostomy or Roux-en-Y reconstruction in 2 cases (Type Ⅴ). Conclusion Correct diagnosis and appropriate surgery for SMAS lead to satisfactory outcomes.