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Objective To explore the effect of mucle force on contact force, peak pressure and contact area of foot joint in in vitro biomechanical experiment of foot and ankle, so as to provide references for choosing appropriate loading modes. Methods In neutral position of the ankle joint, fresh calf and foot specimens were simulated with or without mucle force loading. The contact force, peak pressure and contact area of the 1st metatarsophalangeal joint, the 2nd metatarsophalangeal joint, the 1st tarsometatarsal joint, the 2nd tarsometatarsal joint, the medial cuneonavicular joint, the intermediate cuneonavicular joint, the talonavicular joint, the calcicocuboid joint, the subtalar joint ( posterior articular surface) and the tibiotalar joint of normal foot under loading were measured, the results are compared and analyzed. Results Under muscle force loading, the contact force of the 1st metatarsophalangeal joint, the 2nd metatarsophalangeal joint, the 1st tarsometatarsal joint,the 2nd tarsometatarsal joint, the medial cuneonavicular joint, the intermediate cuneonavicular joint, the talonavicular joint and the tibiotalar joint were significantly greater than those without muscle force loading (P<0. 05), and the change percentages were 719. 28% , 311. 37% , 128. 67% , 50. 82% , 54. 89% , 57. 63% ,79. 98% and 50. 34% , respectively. The peak pressures of the 1st metatarsophalangeal joint , the 1st tarsometatarsal joint and the talonavicular joint under muscle force loading were significantly higher than those without muscle force loading ( P < 0. 05), and the change percentages were 176. 14% , 62. 91% and 40. 07% ,respectively. The contact area of the 1st metatarsophalangeal joint, the 1st tarsometatarsal joint, the intermediate cuneonavicular joint and the subtalar joint ( posterior articular surface) under muscle force loading increased significantly (P<0. 05), and the change percentages were 132. 20% , 55. 41% , 30. 97% and 26. 87% , respectively. Conclusions In biomechanical experiment of foot and ankle specimens, muscle force loading has a significant effect on contact force, peak pressure and contact area of each foot joint, especially the forefoot.Therefore, it is necessary to consider the effect of muscle force loading on stress of foot and ankle in the study ofrelated in vitro specimens
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<p><b>OBJECTIVE</b>To construct a three-dimensional (3D) liver model of Wuzhishan mini-pig for virtual liver surgeries.</p><p><b>METHODS</b>The biliary tree and hepatic arteries of Wuzhishan mini-pig were perfused with perchloroethylene and ethyl acetate along mixed with lead oxide, and the hepatic vein and portal vein were perfused with a mixture of dental base acrylic resin and lead oxide. The sectional images were acquired using a 64-slice spiral CT, and the 3D models of the portal vein, hepatic vein, biliary tree, hepatic arteries, and liver parenchyma were reconstructed using Mimics software; the resection image of the liver was also designed. The intrahepatic vascular cast was prepared by corroding the soft tissue with hydrochloric acid.</p><p><b>RESULTS AND CONCLUSION</b>The intrahepatic vascular cast obtained fully retained the vascular architecture and displayed the fifth- and sixth-level branches of the hepatic vein and portal vein and the third- and fourth-level branches of the artery and bile duct. The 3D model of liver allowed stereoscopic and accurate display of the third- and fourth-level branches of the hepatic vein and portal vein and the second- and third-level branches of the artery and bile duct. The 3D model showed fewer branches but represented the structural distribution identical to the cast. The 3D model could clearly display the spatial relationship between the vasculature and the soft tissue in virtual resection of the liver tissues, and thus provides a useful model for training of laparoscopic liver resection.</p>
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Animals , Bile Ducts , Hepatic Artery , Hepatic Veins , Imaging, Three-Dimensional , Liver , Models, Anatomic , Portal Vein , Swine , Swine, Miniature , Tomography, Spiral ComputedABSTRACT
<p><b>BACKGROUND</b>To evaluate the significance of flow cytometry (FCM) in the analysis of multi-drug resistance of doxorubicin.</p><p><b>METHODS</b>The level of doxorubicin or Rh-123 in S-180R and BGC-823/DOX, which were two cell lines with different drug resistance, was measured by FCM comparatively and continuously.</p><p><b>RESULTS</b>The total fluorescence profile peaks of S-180R, a high resistant cell line, were predominantly different from those of S-180, the parent cell line, by the FCM analysis. The subtle fluorescence profile differences between BGC-823/DOX (a low resistant cell line) and the parent cell line were quantitatively measured on the FCM map. The changes of each resistant cell fluorescence from the S 180R cells could be displayed by continuous tests, the more near the fluorescence level of each cell was, the more the fluorescence pike of whole cells centralized.</p><p><b>CONCLUSIONS</b>FCM is a sensitive, accurate and quantitative test in the analysis of doxorubicin drug resistance.</p>
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<p><b>OBJECTIVES</b>To summarize the clinical experience of preoperative intraarterial chemotherapy (PRAC) and evaluate the long-term results of multimodality against colorectal cancer.</p><p><b>METHODS</b>Seldinger procedure was used to intubate the tube to the artery branch which supplied blood to the tumor. The tumor was imaged to make sure the diagnosis and irrigate the chemotherapeutic drugs. Ten days after PRAC, the patients received radical operation and 6 chemotherapeutic courses with FCF regimen. Concurrent patients receiving surgical treatment yet no PRAC therapy were chosen as controls.</p><p><b>RESULTS</b>One-year survival rate was 93.05% in the PRAC group and 80.78% in the controls (P = 0.023). COX multivariate analysis was used to analyse the prognostic factors. Dukes'staging and the PRAC prescription or not were found to be independent prognostic factors of colorectal cancer patients. Patients in the PRAC group survived longer than those in the control group.</p><p><b>CONCLUSION</b>PRAC can improve the survival of colorectal cancer patients.</p>
Subject(s)
Female , Humans , Male , Middle Aged , Antineoplastic Agents , Colorectal Neoplasms , Drug Therapy , Mortality , Pathology , Infusions, Intra-Arterial , PrognosisABSTRACT
0.05). Only tumor classification and cell differentiation were proved to be independent factor determing the outcome (P
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ObjectiveTo determine the effects of combination of parenteral nutrition(PN) with enteral nutrition (EN) on patients with gastric cancer in perioperative period of total gastrectomy . MethodsIn 52 patients with advanced gastric cancer, 41 had PN support preoperatively and all 52 patients received combination of PN with EN after the total gastrectomy. Results48 of the 52 patients whose intestinal function was recovered within 3 days postoperatively. When using EN, 5 cases felt borborygmus,abdominal pain or mild diarrhea, but these symptoms decreased by slowing down of the infusion speed. The concentration of plasma albumin showed a marked increase on the 10th postoperative day(P
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Objective To evaluate the feasibility in early diagnosis, predicting therapeutic effect, recurrence monitoring by examining promoter hypermethylation for cancer-associated genes E-cadherin in cancer tissue and peripheral blood of breast cancer patients. Methods The tumor tissue, paracancer- tissue and the paired plasma were examined for aberrant methylation of E-cadherin gene by methylation-specific PCR in 42 cases of breast cancer and 10 cases of breast benign diseases. Results The incidence of promoter hypermethylation of E-cadherin in tumor tissues was 52.4% and the paired plasma were 33.3%. E-cadherin hypermethylation in plasma samples and tumor samples significantly correlated with each other ( P
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A double-copy Moloney leukemia virus-based retroviral vector containing both the Neo~(R) gene and a mutant human dihydrofolate re-ductase(S31 mutation) cDNA was packaged into the Amphotropic packaging cell hne GP-EAM12( AM12), and a Amphotropic producer cell hne (named AM12-S31)was obtained. In this study, we investigated its drug resistant characteristics, viral titer and for murine hematopoietic progenitor cells transduction as well. MTT assay verified that the AM12-S31 cells were resistant to G418 and methotrexate(MTX), the IC50 were more than 800 ?g/ml and 100 ?M respectively while the control cell line AM12 was sensitive to both drugs, the IC50 were 180 ?g/ml and 10 ?M, respectively. The viral titer for this cell line was approximately 7.8? 104~4.2? 105 G418-resistant colony forming units/ml. The replication-competent virus can not be detected in this producer cell line. We also use the AM12-S31 cells to transfect murine hematopoietic cells (By coculture) . The positive colonies were found in all the G418 concentrations using CFU-GM assay. No G418-resistant colony was found using AM12 transfection. The infected murine marrow cells were returned to lethally irradiated(900rad)recipients. The murine transplanted with AM12-S31 infected marrow cells showed protection from lethal MTX toxicity as compared with AM12 infected animals. Evidence for integration and the proviral DNA was obtained by PCR amplification of proviral DNA. These results indicated this producer cell hne could produce high titer, high-efficiency and non-replcational competent virus. The murine marrow cells could be transfected successfully using this system, and express the foreign gene. The lethal irradiated murine marrow function could be reinstitution by infusing the hematopoietic progenitor cells tranducted with human mutant dihydrofolate reductase. In my opinion, this system would play an important role in research the long-term protection of murine marrow hematopoietic function and drug resistant gene therapy.
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Objective To investigate the expression of cyclooxygenase-2 in hepatocelluar carcinoma cell lines. Methods RT-PCR and immunocytochemistry were use d to investigate the expression of cyclooxygenase-2 in 6 hepatocellular carcino ma cell lines. Result COX-2 mRNA expression was detected in five of six cell lines, and all six cell lines w ere positive for COX-2 protein expression. Conclusion COX-2 is expressed in hepatocellular carcinoma cell li nes, providing basis for the chemoprevention of hepatocelluar carcinoma.