Neuronal plasticity regulated by the insulin-like signaling pathway underlies salt chemotaxis learning in Caenorhabditis elegans

Quantification of neuronal plasticity in a living animal is essential for understanding learning and memory. Caenorhabditis elegans shows a chemotactic behavior toward NaCl. However, it learns to avoid NaCl after prolonged exposure to NaCl under starvation conditions, which is called salt chemotaxis learning. Insulin-like signaling is important for this behavioral plasticity and functions in one of the salt-sensing sensory neurons, ASE right (ASER). However, how neurons including ASER show neuronal plasticity is unknown. To determine the neuronal plasticity related to salt chemotaxis learning, we measured Ca(2+) response and synaptic release of individual neurons by using in vivo imaging techniques. We found that response of ASER increased whereas its synaptic release decreased after prolonged exposure to NaCl without food. These changes in the opposite directions were abolished in insulin-like signaling mutants, suggesting that insulin-like signaling regulates these plasticities in ASER. The response of one of the downstream interneurons, AIB, decreased profoundly after NaCl conditioning. This alteration in AIB response was independent of the insulin-like signaling pathway. Our results suggest that information on NaCl is modulated at the level of both sensory neurons and interneurons in salt chemotaxis learning.     

Surgical Treatment for Hepatocellular Carcinoma Detected After Successful Interferon Therapy

Purpose Interferon therapy suppresses the development of hepatocellular carcinoma (HCC) and tumor recurrence after a resection of HCC in patients with chronic hepatitis C. However, the value of a liver resection and which method is best for the treatment of HCC detected after successful interferon therapy remains to be clarified. The risk factors for tumor recurrence after a liver resection for HCC detected after successful interferon therapy were investigated to determine the appropriate operative method for such HCC. Methods Risk factors including the clinicopathologic findings and the operative methods for tumor recurrence were evaluated by univariate and multivariate analyses in 24 patients who underwent liver resection for HCC detected after successful interferon therapy (sustained viral response or biochemical response). Results According to a univariate analysis, large tumor (>2 cm, P = 0.0326), multiple tumors (P = 0.0372), nonanatomic resection (P = 0.0103), and positive surgical margin (<5 mm of a free surgical margin, P = 0.0245) were possible risk factors for short tumor-free survival time after surgery. A multivariate analysis showed that large tumor (P = 0.0407), nonanatomic resection (P = 0.0215), and positive surgical margin (P = 0.0253) were independent risk factors for a short tumor-free survival time after surgery. Conclusion An anatomic resection with an appropriate surgical margin (≥5 mm of a free surgical margin) is recommended for patients with HCC detected after successful interferon therapy.     

Clinicopathological characteristics of patients with hepatocellular carcinoma after hepatectomy: relationship with status of viral hepatitis

BACKGROUND AND OBJECTIVES: Viral hepatitis may modulate the status of liver dysfunction, tumor biology, and postoperative course in patients with hepatocellular carcinoma (HCC). METHODS: To determine the characteristics of HCC in different types of viral hepatitis, we conducted a comparative analysis of clinicopathological features and outcomes in 243 Japanese HCC patients following hepatic resection. Patients were divided into four groups; non-B-non-C group, hepatitis B (HBV) group, hepatitis C (HCV) group, and co-infection with HB, and HC (HBCV) group. RESULTS: Liver function was worst and prevalence of cirrhosis was highest in HBCV group than in compare to HBV and non-B-non-C group. The prevalence rates of intrahepatic metastasis, tumor vascular involvement, and low curability in HBCV group were higher than in the other groups. Uncontrolled ascites and hepatic failure were significantly more common in HBCV group than other groups. The disease-free and overall survival rates of non-B-non-C group were better than those of the other groups; both survival rates were the worst in HBCV group than the other groups. CONCLUSIONS: HCC patients with co-infection of HBV and HCV had poorer liver function and more advanced tumors compared with the other groups. This might explain the poor prognosis of such patients.     

Reconstruction after total gastrectomy

Reconstruction after total gastrectomy should be assessed based on the simplicity and safety of the procedure and postoperative digestive function. A survey performed by the Japan Gastric Cancer Association showed that the Roux-en-Y and small bowel interposition are the most common reconstructive procedures after total gastrectomy. Laparoscopic total gastrectomy is not yet the standard procedure under the Japanese guidelines for the treatment of gastric cancer. The most common reconstructive procedure after laparoscopic total gastrectomy is the Roux-Y, although the anastomotic procedure remains controversial.     

Incidence and management of bile leakage after hepatic resection for malignant hepatic tumors

BACKGROUND: Bile leakage is one of the frequent and disturbing complications of hepatic resection. STUDY DESIGN: Clinical records of the 363 patients who underwent hepatic resections without biliary reconstruction for hepatic cancers between January 1994 and June 2001 were reviewed. Postoperative bile leakage was defined as continuous drainage with a bilirubin concentration of 20 mg/dL or 1,500 mg/d lasting 2 days. Leakage that continued longer than 2 weeks or that required surgical intervention was defined as uncontrollable. Differences in incidence and frequency of uncontrollable leakage for the different types of hepatic resection, tumors, and underlying liver disease were investigated. Outcomes after treatment for uncontrollable bile leakage were also reviewed. RESULTS: Postoperative bile leakage occurred in 26 of 363 patients (7.2%). Although the incidence in patients with cholangiocellular carcinoma (3/9 [33%]) was higher (p = 0.03) than in patients with hepatocellular carcinoma, rates of occurrence were similar among the different types of hepatic resection and underlying liver disease. Eight of the 26 patients (31%) had uncontrollable leakage. Two patients required reoperation to control leakage; one of these developed hepatic failure and died 2 months after surgery. Four patients underwent endoscopic nasobiliary drainage 21 to 34 days after hepatectomy, and the leakage resolved within 3 to 21 days. Fibrin glue sealing was effective in two patients whose leaking bile ducts were not connected to the common bile duct. CONCLUSIONS: Although meticulous surgical technique can minimize the risk of postoperative bile leakage, some instances of leakage are unavoidable. Nonsurgical treatments, such as nasobiliary drainage or fibrin glue sealing, are preferable to reoperation.     

A clinicopathological study of gastric stump carcinoma following proximal gastrectomy

Background  We aimed to clarify the frequency and clinicopathological characteristics of gastric stump carcinoma following proximal gastrectomy. Methods  Three-hundred and sixteen patients who had undergone curative proximal gastrectomy over a 21-year period from January 1984 through December 2004 were reviewed. Results  Gastric stump carcinoma was observed in 17 patients (5.4%). The time interval between the initial gastrectomy and the treatment of gastric stump cancer was within 5 years in 3 patients, within 5–10 years in 8, and after 10 years in 6. Treatment included endoscopic resection (n = 4), completion total gastrectomy of the remnant stomach (n = 11), pancreatoduodenectomy (n = 1), and nonsurgical resection (n = 1). Pathologically, 9 carcinomas were differentiated and 8 were undifferentiated. In a review of reconstruction methods associated with disease stage, stage I was found in 6 of the 7 patients with esophagogastrostomy or short-segment jejunal interposition. On the other hand, stage I was found in only 3, but stage II–IV was found in 7 of the 10 patients with reconstruction by double-tract or long-segment jejunal interposition; thus, the tumor was more likely to be detected at an advanced stage after long-segment interposition (P = 0.049). Conclusion  Gastric stump carcinoma following proximal gastrectomy occurred at a high frequency of 5.4% of initial resections. It is necessary to select a reconstruction method that facilitates postoperative endoscopic examination, as well as to follow up the patients after proximal gastrectomy in the long term for the early detection and early treatment of gastric stump carcinoma.     

Serum 25-hydroxyvitamin D3 Levels and Diabetes in a Japanese Population: The DOSANCO Health Study

BackgroundBoth decreased insulin sensitivity and impaired insulin secretion are common in Asian populations with diabetes, in contrast to Western populations. There is limited evidence regarding the association between insulin response in diabetes in Asian populations and serum 25-hydroxyvitamin D₃ (25[OH]D₃) insufficiency.MethodsThe present cross-sectional study compared the prevalence of diabetes, defined as a fasting plasma glucose level ≥126 mg/dL and/or a HbA1c level ≥6.5%, among 480 participants aged 35–79 years not taking anti-diabetes medications, based on serum 25(OH)D₃ levels. A logistic regression model was used to calculate the odds ratios for diabetes in each serum 25(OH)D₃ group. Furthermore, this study examined the association between serum 25(OH)D₃ levels and the index of homeostasis model assessment of insulin resistance (HOMA-IR) using a linear regression model.ResultsThe prevalence of diabetes was 7.29% in the study population, and was higher in lower serum 25(OH)D₃ quartile groups. The odds ratios for diabetes in the first, second, and third serum 25(OH)D₃ quartile groups (25[OH]D₃: ≤18.10, 18.11–22.90, and 22.91–28.17 ng/mL) were 4.02 (95% confidence interval [CI], 1.25–12.92), 2.50 (95% CI, 0.77–8.10), and 1.91 (95% CI, 0.60–6.09), respectively, with the fourth quartile group ( ⩾ 28.18 ng/mL) serving as the reference group, after adjusting for sociodemographic, lifestyle, physical and environmental factors. Serum 25(OH)D₃ levels showed an inverse association with log-transformed HOMA-IR after adjusting for similar factors (standardized β = −0.08; 95% CI, −0.14 to −0.02).ConclusionSerum 25(OH)D₃ levels were inversely associated with diabetes prevalence in a general Japanese population, with a slight inverse association between serum 25(OH)D₃ levels and HOMA-IR.Key words: 25-hydroxyvitamin D₃, diabetes, insulin resistance, Japanese