[GC-box is not a key cis-acting element in human insulin gene promoter].

Objective: To identify whether GC-box (-348 to -338) in human insulin gene promoter is a key cis-acting element.

Methods: Human insulin gene promoter was sub-cloned into secreted alkaline phosphatase (SEAP) reporter plasmid. The deletion and mutation of GC-box in insulin gene promoter was performed.

Glucose-dependent expansion of pancreatic beta-cells by the protein p8 in vitro and in vivo.

p8 protein expression is known to be upregulated in the exocrine pancreas during acute pancreatitis. Own previous work revealed glucose-dependent p8 expression also in endocrine pancreatic beta-cells. Here we demonstrate that glucose-induced INS-1 beta-cell expansion is preceded by p8 protein expression.

Inhibition of preproinsulin gene expression by leptin induction of suppressor of cytokine signaling 3 in pancreatic beta-cells.

Leptin inhibits insulin secretion and preproinsulin gene expression in pancreatic beta-cells, but signal transduction pathways and molecular mechanisms underlying this effect are poorly characterized. In this study, we analyzed leptin-mediated signal transduction and preproinsulin gene regulation at the molecular level in pancreatic beta-cells. Leptin stimulation led to janus kinase (JAK)2-dependent phosphorylation and nuclear translocation of the transcription factors signal transducer and activator of transcription (STAT)3 and STAT5b in INS-1 beta-cells.

Mechanism of benign biliary stricture: a morphological and immunohistochemical study.

Aim: To explore the mechanism of benign biliary stricture.

Methods: A model of trauma of bile duct was established in 28 dogs. The anastomosed tissues were resected and examined by light and electron microscopes on day 3, in wk 1, 3 and mo 3, 6 after operation.

Relationship between inducible nitric oxide synthase expression and angiogenesis in primary gallbladder carcinoma tissue.

Aim: To explore the relationship between angiogenesis and biological behaviors of primary gallbladder carcinoma (PGBC), the relationship between the expression of inducible nitric oxide synthase (iNOS) and biological behaviors of PGBC and its relationship with the expression of iNOS and angiogenesis of PGBC.

Methods: The expression of iNOS and micro-vessel density (MVD) were assessed by immunohistochemical method and image analysis system in 40 specimens of PGBC and in 8 specimens of normal gallbladder. The immunostaining results and related clinicopathologic materials were analyzed by statistical methods.