Sulfated vizantin causes detachment of biofilms composed mainly of the genus Streptococcus without affecting bacterial growth and viability.

BACKGROUND: Sulfated vizantin, a recently developed immunostimulant, has also been found to exert antibiofilm properties. It acts not as a bactericide, but as a detachment-promoting agent by reducing the biofilm structural stability. This study aimed to investigate the mechanism underlying this activity and its species specificity using two distinct ex vivo oral biofilm models derived from human saliva. RESULTS: The biofilm, composed mainly of the genus Streptococcus and containing 50 µM of sulfated vizantin, detached significantly from its basal surface with rotation at 500 rpm for only 15 s, even when 0.2% sucrose was supplied. Expression analyses for genes associated with biofilm formation and bacterial adhesion following identification of the Streptococcus species, revealed that a variety of Streptococcus species in a cariogenic biofilm showed downregulation of genes encoding glucosyltransferases involved in the biosynthesis of water-soluble glucan. The expression of some genes encoding surface proteins was also downregulated. Of the two quorum sensing systems involved in the genus Streptococcus, the expression of luxS in three species, Streptococcus oralis, Streptococcus gordonii, and Streptococcus mutans, was significantly downregulated in the presence of 50 µM sulfated vizantin. Biofilm detachment may be facilitated by the reduced structural stability due to these modulations. As a non-specific reaction, 50 µM sulfated vizantin decreased cell surface hydrophobicity by binding to the cell surface, resulting in reduced bacterial adherence. CONCLUSION: Sulfated vizantin may be a candidate for a new antibiofilm strategy targeting the biofilm matrix while preserving the resident microflora.

Clinicopathological characteristics of advanced colorectal cancer 30 mm or smaller in diameter.

OBJECTIVE: To investigate the clinicopathological characteristics of advanced colorectal cancer which was 30 mm or smaller in diameter. METHODS: Retrospective analysis documented 80 patients with small advanced colorectal cancer from May 1985 to May 2002. According to the diameter of tumors, all patients were divided into three groups: Group A (10 mm or less), Group B (11-20 mm), Group C (21-30 mm). Considering the number of patients in Group A was smaller, we combined Group A with Group B as Group D. Then various clinicopathological characteristics were compared between Group C and Group D. RESULTS: The most common site of small advanced colorectal cancer was sigmoid colon and rectum that accounted for 36.2% and 35.0% of all cases. The average diameter of total tumors was 23.3 mm. Type 2 was the most common macroscopic type (63.7%) and the moderate differentiation was seen in 77.5% of cases. Thirty-eight (47.5%) cases had lymph node metastasis. Three (3.8%) cases had liver metastasis and three (3.8%) cases had peritoneal metastasis. The frequency of lymph node metastasis was found significantly different between Group C and Group D (54.2% vs. 28.6%, P < 0.05) , as well as between the groups with different depth of invasion (P < 0.05). Curability A resection was performed in 69 (86.2%) cases. CONCLUSIONS: Tumor size and depth of invasion are related to lymph node metastasis in small advanced colorectal cancer. However, the small size of tumor may not always be a reliable parameter for estimating the risk of lymph node metastasis. Small colorectal cancers also do not always mean the early stage. Surgeons should be aware of the features of small advanced colorectal cancers to select ideal management and perform perfect resection.

Imaging findings in primary adenosquamous carcinoma of the liver: a case report.

Adenosquamous cell carcinoma is characterized by both squamous and glandular components, and is a rare disease of the liver that is the subject of few reports in the literature. We present a case in which the imaging findings on CT, MRI, and hepatic arteriography, as well as pathological correlation of the tumor and the clinical history, aided in including this entity in the differential diagnosis.

Paraaortic lymph node dissection for gastric cancer in 244 consecutive cases.

BACKGROUND/AIMS: More than 20% of patients with advanced gastric cancer show paraaortic lymph node metastasis. However, whether extensive paraaortic lymphadenectomy is beneficial remains controversial. We performed a prospective study of paraaortic lymphadenectomy for patients with advanced gastric cancer. METHODOLOGY: From January 1991 to March 2004, 244 consecutive patients with advanced gastric cancer underwent gastrectomy with paraaortic lymphadenectomy with curative intent. The patients were divided into 3 groups according to the period: Group 1 (1991-1995), Group 2 (1996-1999), and Group 3 (2000-2004). RESULTS: Overall mortality rate was 2.4%, and it fell rapidly from 7.1% in Group 1 to 0% in Group 3. Postoperative complications occurred in 35.6%. High age and postoperative complications were significant predictive factors for operative death. Preoperative comorbidity, positive distal margin, and pancreatectomy were significant predictive factors of postoperative complications. Depth of cancer invasion was correlated with paraaortic node metastasis. Ten patients with paraaortic node metastases survived for more than 5 years. Operative curability and postoperative complications were significant prognostic factors for patients who underwent this procedure. CONCLUSIONS: Paraaortic lymph node dissection for gastric cancer should be performed in patients with tumors deeper than the serosa. Pancreatectomy should be avoided, with careful management required in cases of unavoidable pancreatectomy.

[Results of local ablation therapy for liver metastases from colorectal cancer using radiofrequency ablation and microwave coagulation therapy (RFA/MCT)].

UNLABELLED: In addition to hepatectomy and chemotherapy with intra-arterial infusion, local ablation therapy using RFA and MCT has been used for treatment of liver metastases derived from colorectal cancer. We investigated the results of local ablation therapy in such cases conducted at our department. SUBJECTS AND METHODS: This study was conducted in 9 out of 21 patients with liver metastases derived from colorectal cancer, who underwent local ablation therapy with RFA from September 2001. As adjuvant therapy, the divided administration of low-doses CDDP/FU was conducted in all cases. RESULTS: RFA and MCT were used in 9 cases (25 lesions) and in 15 cases (82 lesions), respectively. The three cases of RFA were combined with MCT. The severity of liver metastasis was H1 and H2 in one case each and H3 in seven cases. The tumor diameter was 1.0-4.7 cm (mean, 2.7 cm) and patients underwent cauterization from 1-6 times (mean, 2.4 times). Although there were no critical complications, pyrexia and increased AST/ALT were found. The three-year survival rate was 50%, and thus favorable prognoses were obtained. CONCLUSION: There were no notable complications associated with local ablation therapy for liver metastases derived from colorectal cancer, and this method was thus indicated to be effective for local control in cases in which hepatectomy is impossible.

Rupture of infectious aneurysm of the thoracic aorta into the lung after radical esophageal cancer surgery.

A 60-year-old male underwent radical operation for esophageal cancer 45 days prior to complaining of several incidents of hemoptysis. The hemoptysis was found to be caused by infectious aneurysm of the descending thoracic aorta penetrating the lung. The aneurysm was resected and the aortic wall was sutured directly under percutaneous circulatory pulmonary support system. The sutured thoracic aorta was wrapped with the pedicle of an intercostal muscle flap to prevent reinfection. Forty-eight days after the aortic wall suture operation, however, the patient experienced massive hemoptysis and went into shock. Angiography was reveal no arterial lesions, so emergency left lower lobectomy was performed on suspicion of lung vessel rupture. Immediately after the lower lobectomy, recurrence of the aortic wall rupture caused uncontrollable bleeding. The patient died intraoperatively.

Primary hepatic non-Hodgkin's lymphoma in a patient with chronic hepatitis C: report of a case.

We report a case of primary hepatic non-Hodgkin's lymphoma in a 77-year-old man with chronic hepatitis C. Laboratory data revealed slightly elevated liver function parameters and positive antibody for hepatitis C virus (HCV). Abdominal ultrasonography showed a low-echogenic tumor, about 5 cm in diameter, in the left lateral segment. Abdominal computed tomography showed that the tumor was marginally enhanced in the early phase, but no enhancement was seen in the late phase. Magnetic resonance imaging showed that the tumor was hypointense in relation to the liver on T1-weighted images, but hyperintense on T2-weighted images. Hepatic angiography showed a homogeneously stained hypervascular tumor. Under the diagnosis of a liver tumor, thought to be a hepatocellular carcinoma, left lateral segmentectomy was performed. Histological examination confirmed a diagnosis of non-Hodgkin's diffuse large B-cell lymphoma that was positive for L-26 and CD79Alpha, but negative for CD3 and UCHL-1. The surrounding liver tissue showed signs of chronic active hepatitis. Multiple recurrent lesions were found in the liver, spleen, and iliac bones 4 months postoperatively. However, complete remission was achieved after five courses of systemic chemotherapy using pirarubicin, cyclophosphamide, vincristine sulfate, and prednisolone. The patient has been carefully followed up for about 1 year since his operation, and has been doing well. We review the literature on primary non-Hodgkin's lymphoma arising in the liver infected by HCV.