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Mechanical properties of steel–concrete interfaces are evaluated on the basis of three existing experimental evidences. The properties include bond strength, unbonded and bonded friction parameters, residual level of the friction parameter, normal fracture energy release rate, bonded and unbonded slip fracture energy release rates under different levels of normal stress, and shape parameters defining the geometrical shape of the failure envelope. For this purpose, a typical type of constitutive model for describing steel–concrete interface behavior is presented based on a hyperbolic three-parameter failure criterion. The constitutive model depicts the strong dependency of interface behavior on bonding condition of the interface, bonded or unbonded. Mechanical roles of the interface parameters are discussed with reference to those of the presented interface constitutive model. Values of the interface parameters are determined through interpretation of existing experimental results, geometry of the failure envelope and sensitivity analyses. These values are applied to push-out tests of concrete-infilled rectangular steel columns with three different cases of interface lengths. The failure process of concrete-infilled rectangular steel columns is discussed through comparison of experimental measurements with numerical results.

R&D Center, MIDAS IT, Seongnam 462-807, KoreaABSTRACT Mechanical properties of steel-concrete interface were evaluated on the basis of experimental observations. Theproperties included bond strength, unbounded and bonded friction angles, residual level of friction angle, mode I fracture energy,mode II bonded fracture energy and unbonded slip-friction energy under different levels of normal stress, and shape parametersto define geometrical shape of failure envelope. For this purpose, a typical type of constitutive model of describing steel-concreteinterface behavior was presented based on a hyperbolic three-parameter Mohr-Coulomb type failure criterion. The constitutivemodel depicts the strong dependency of interface behavior on bonding condition of interface, bonded or unbounded. Values of theinterface parameters were determined through interpretation of experimental results, geometry of failure envelope and sensitivityanalysis. Nonlinear finite element analysis that incorporates steel-concrete interface as well as material nonlinearities of concreteand steel were performed to predict the experimental results. Keywords : steel-concrete interface, interface parameter, Mohr-Coulomb failure criterion, confining pressure, interface finite ele-ment analysis

Experiments on steel-concrete interface are performed to investigate and determine the mechanical roles and prop- erties of interface parameters. The intrinsic different nature of bonded and unbonded interfaces are addressed based on the exper- imental observations that were obtained from two types of tests considering bonded and unbonded interfaces. The unbonded tests are performed for the specimens that are in unbonded when the initially bonded specimens are tested first. Four cases of lateral confinements including pure slip, and low and medium levels of lateral pressure are taken into account to investigate the effects of lateral confinements on interface behavior. It is shown that the maximum shear strengths, the levels of residual strengths and the Mode II fracture energy release rates are linearly related to the confinement levels. Based on the experimental evidences obtained from this study, the values of interface parameters required in a steel-concrete interface constitutive model will be pre- sented in the companion paper.

The intraoperative assessment of lymph node status is important when performing limited surgery in gastric cancer patients. Currently available techniques for this assessment are frozen section, imprint cytology, and other molecular methods; most current studies use the frozen-section method. In the present study, we focused on the accuracy and feasibility of imprint cytology as a tool to assess lymph node status intraoperatively in gastric cancer surgery.Between April 2001 and March 2003, we performed imprint cytology of the sentinel nodes in 260 consecutive patients. After review by an experienced cytopathologist, the sensitivity, specificity, and overall accuracy of the method were determined.The time required for the intraoperative imprint cytology was 8 min, and the sensitivity, specificity, and overall accuracy were 52.2%, 88.8%, and 73.8%, respectively.Imprint cytology could be a useful technique for the assessment of lymph node status intraoperatively if the sensitivity and specificity can be improved to an acceptable level.

Intrahepatic cholangiocarcinoma (ICC) is a rare primary malignant liver tumor with an extremely poor prognosis. Recently its incidence has increased, however, little attention has been directed to factors related to its molecular carcinogenesis, including oncogenes, tumor suppressor genes and cell cycle-related proteins. ICC is generally characterized by strong proliferation, invasion and early metastasis. These biological behaviors of ICC, with respect to the genetic and molecular aspects, remain to be clarified. In this study, we performed a proteomic analysis to identify the proteomic alterations associated with carcinogenesis of ICC. Protein expression profiles of sixteen cases of ICC were compared with those of adjacent non-involved bile duct tissue. Among the 151 protein spots that showed a statistically significant expression difference (P

Although natural orifice extraction is now widely performed, there have been no reports of this procedure following subtotal gastrectomy for gastric cancer. This report describes trans-vaginal specimen extraction in four patients with early gastric cancer. The clinical data of four patients with early gastric cancer were reviewed. Totally laparoscopic subtotal gastrectomy and D1 + β lymph node dissection was performed using five trocars and a conventional procedure. Posterior colpotomy was performed by an experienced gynecologist, who retrieved the specimens in a retrieval bag via the trans-vaginal route. The colpotomy site was repaired immediately following specimen removal. Reconstruction was performed using the intracorporeal Billroth II method and an endo-GIA 60. Totally laparoscopic subtotal gastrectomy and trans-vaginal specimen extraction was successfully accomplished in all patients without intraoperative complications. The present technique may be a safe and feasible operative procedure for some limited groups of elderly female patients with early gastric cancer.

Understanding the molecular background of breast cancer biology is critical in developing new biomarkers for earlier diagnosis and more optimized treatment. We performed a proteomic analysis of human breast carcinoma tissues to investigate the tumor-specific protein expression in breast carcinoma. Using 2-dimensional electorphoresis (2-DE) and matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS), we were able to identify a list of proteins which are upregulated in cancerous tissue. There was significant increase of galectin-1 expression in all cancerous tissues compared to noncancerous tissues, and its increased expression was further confirmed by western blot immunostaining. Subsequent immunohistochemical staining against galectin-1 in 105 breast cancer specimens showed significant correlation between galectin-1 expression in cancer-associated stromal cells and tumor invasiveness, T stage, TNM stage, and axillary lymph node metastasis. Galectin-1 expressionin cancer cells showed no correlation to above-mentioned pathologic variables. Hormonal receptor status and galectin-1 expression showed no correlation. This study demonstrates the upregulation of galectin-1 in breast carcinoma tissues and the clinical significance of galectin-1 in breast cancer patients. Our data supports the recently highlighted roles of galectin-1 in cancer-associated stroma and in tumor immune privilege. © 2006 Wiley-Liss, Inc.

Backgrounds Angiosarcoma occurs very rarely in the gastrointestinal tract and can present great diagnostic difficulty, especially when it is associated with intraabdominal abscess or granulation tissue. Case presentation We report a case where the angiosarcoma was diagnosed after the occurrence of disseminated angiosarcoma and concurrent hemoperitoneum. The tumor developed in the fibrous capsule of a foreign body, which was possibly related to the previous appendectomy twenty years ago, and became a widely disseminated malignant neoplasm in the abdomen. After the operation, the patient's course was dominated by a fatal consumptive coagulapathy. Pathologic examination of the multiple intra-abdominal lesions showed the histological and immunohistological characteristics of the angiosarcoma. Conclusion Even though angiosarcoma in the gastrointestinal tract is extremely rare, when dealing with intraabdominal abscess or the gastrointestinal bleeding in patients who have undergone surgery or radiation therapy in the past, the possibility of angiosarcoma should be considered. To make the definite diagnosis of angiosarcoma and to avoid the misdiagnosis of foreign body granuloma, thorough histological examination and immunohistochemical staining may be prerequisite.

Purpose: The aim of this study was to investigate the risk factors of reflux associated complications (reflux symptoms, reflux esophagitis, and esophageal stricture) after gastrectomy for proximal gastric cancer. Methods: 150 patients with proximal gastric cancer were included from January 2005 to December 2008. Their medical and surgical records were retrospectively analyzed concerning clinical and pathologic characteristics, operation methods, morbidity, reflux associated complications and nutritional states. Results: Tumor sizes and operation methods were statistically significant in univariate analysis of risk factors for reflux associated complications (P＜0.05). However, only operation methods were statistically significant in multivariate analysis (P=0.00). We, thus, compared operation methods. There were no significant differences in morbidity, body weight, hemoglobin, serum cholesterol, protein and albumin between total gastrectomy groups and proximal gastrectomy groups (P＞0.05). However, reflux complications were significantly more common in proximal gastrectomy groups (72.4%) than in total gastrectomy groups (29.5%). Severe reflux esophagitis (LA classification C or D) was found in only proximal gastrectomy groups. Conclusion: Total gastrectomy is favorable for proximal early gastric cancer in terms of reduced esophageal reflux complications.

Purpose: Combined organ resection is a common operation in gastric cancer surgery. The aim of this study is to investigate the risk of combined minor organ resection (GB, gynecologic organ, appendix etc) in gastric cancer surgery. Methods: The clinical data from 673 consecutive patients who underwent gastrectomy for gastric cancer at a single center were retrospectively analyzed. We investigated clinical data between open groups (OG) and laparoscopy groups (LAG), and we divided the patients into 3 groups: no resection group, minor organ resection group and major organ (spleen, pancreas, and colon) resection group. Results: There were higher complication rates in major organ resection group (59.3%, 53.8%) than no resection (32.3%, 19.1%) or minor organ resection groups (38.7%, 20%) both in OG and LAG (P＜0.05). However, there were longer hospital stays in minor (22.2 days) and major resection groups (24.1) than no resection group (16.2) in OG, but stays were longer in major resection group (30.9) than minor (14.5) and no resection group (16.2) in LAG (P＜0.01). Operative times were longer in minor (287 min) and major organ resection group (310) than no resection group (243) in OG (P＜0.00). However, operation time was longer in major resection group (505) than minor (415) and no resection group (370) in LAG (P=0.00). Conclusion: Combined minor organ resection with gastrectomy does not increase morbidity, and there is no statistical difference in hospital stay and op time than no resection group in LAG.

Purpose: Intraoperative assessment of lymph node status is important when performing limited surgery in gastric cancer patients. Currently available techniques are frozen section, imprint cytology, and other molecular methods, and most current studies use the frozen section method. In the present study, the authors focused on the accuracy and the feasibility of imprint cytology as a tool to assess the lymph node status intraoperatively in gastric cancer surgery. Materials and Methods: Between April 2001 and March 2003, we performed imprint cytology of the sentinel nodes of 260 consecutive patients. After review by an experienced cytopathologist, the sensitivity, the specificity and the overall accuracy were determined. Results: The time required for intraoperative imprint cytology was 8 minutes, and the sensitivity, the specificity and the overall accuracy were 52.2%, 88.8%, and 73.8%, respectively. Conclusion: Imprint cytology can be a useful technique for assessing lymph node status intraoperatively if the sensitivity and the specificity can be improved to an acceptable level.

Purpose: Considering that nutritional state correlates to immunity, we performed this study to evaluate the correlation by assessing the numerical changes of the levels of serum albumin and lymphocyte subsets. Materials and Methods: The study was performed on patients who were diagnosed as having gastric cancer and who underwent curative surgery from August 1998 to August 2004 in the Gyeongsang National University Hospital and whose peripheral blood lymphocyte subsets were tested prior to surgery. The study population was a total of 150 cases. Results: The change in the lymphocyte subsets in relation to the change in the level of serum albumin in all patients with gastric cancer was determined, and was compared to disease stages. When patients were classified by using the level of serum albumin with 3.2 mg/dl as the cut-off point (low group: serum albumin 3.2 mg/dl), the number of peripheral blood lymphocytes, CD3+ cells, CD4+ cells, CD8+ cells, and CD16+ 56 cells were, significantly lower in the group with the level of serum albumin below 3.2 mg/dl (low group) than it was in the group with a serum albumin level above 3.2 mg/dl (normal group) (P

Purpose: The use of laparoscopic surgery for gastric disease has been gaining popularity. However, there has been the controversy over the indications and the standard techniques of laparoscopic gastric surgery in the early gastric cancer (EGC). The purposes of this study were to compare the clinical outcomes among a hand-assisted laparoscopic distal gastrectomy (HALDG), a laparoscopy-assisted distal gastrectomy (LADG), and an open distal gastrectomy (ODG) and to discuss the role of these procedures in the treatment of EGC. Materials and Methods: Between August 2001 and July 2004, laparoscopic surgery was performed in our institution on 25 patients, LADG (n=7) and HALDG (n=18) with EGC. Analysis was performed on clinical data such as the operative time, the hospital stay, the start of oral intake, and the number of harvested lymph nodes. Patients were categorized into early and late groups by using the date of surgery and were also grouped by surgical procedure. To evaluate the feasibility and efficacy of laparoscopic surgery for EGC, we compared the clinical data with those for ODGs performed during the same period. Results: There was no difference in the number of harvested lymph nodes between the laparoscopic group and the open group, but the operation time in the laparoscopic group was longer than that in the open group (P (P