Short reaction of C-peptide, glucagon-like peptide-1, ghrelin and endomorphin-1 for different style diet in type 2 diabetic patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Food composition and style is changing dramatically now, which causes inappropriate secretion of hormones from brain, gastrointestinal and endo-pancreas, may be related to unbalance of glucose in blood. The aim of this study was to explore the fast response of C-peptide, glucagon-like peptide-1 (GLP-1), ghrelin and endomorphin-1 (EM-1) to the eastern and western style meals in patients with type 2 diabetes mellitus.</p><p><b>METHODS</b>The study enrolled 57 patients with type 2 diabetes (20 men and 37 women, mean age (67.05 ± 8.26) years). Eastern style meal (meal A) and western style meal (meal B) were designed to produce the fullness effect. C-peptide, GLP-1, ghrelin and EM-1 were assessed before (0 hour) and after (2 hours) each diet.</p><p><b>RESULTS</b>The delta (2h - 0h) of C- peptide in meal A was significantly lower than that in meal B (P = 0.0004). C-peptide, GLP-1, ghrelin and EM-1 were obviously higher before meal B than those before meal A (P < 0.0001, < 0.0001, = 0.001, = 0.0004 respectively). Blood glucose 2 hours and 3 hours after meal B were higher than those after meal A (P = 0.0005, 0.0079 respectively). Correlations between GLP-1 and ghrelin were strongly positive before both meals and 2 hours after both meals and also in relation to the delta of meal A and meal B (r(A0h) = 0.7836, r(B0h) = 0.9368, r(A2h) = 0.7615, r(B2h) = 0.9409, r(A(2h-0h)) = 0.7531, r((2h-0h))B = 0.9980, respectively, P < 0.0001).</p><p><b>CONCLUSION</b>Western style meal (high fat and protein food) could make more response of C-peptide than eastern style meal, and could stimulate more gut hormones (GLP-1, ghrelin) and brain peptide (EM-1) at the first phase of digestion.</p>

High expression of nucleophosmin/B23 in hepatocellular carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the expression of nucleophosmin/B23 (B23) in tumor cells of hepatocellular carcinoma (HCC) and its clinicopathologic significance.</p><p><b>METHODS</b>Mouse monoclonal antibodies against B23 were raised by recombinant protein and hybridoma technology. Immunohistochemical study for B23 was performed on 103 cases of HCC, 12 cases of focal nodular hyperplasia and 17 cases of native liver tissue adjacent to hepatic hemangioma. Fresh specimens from 10 cases of HCC and the adjacent liver tissue were also collected for reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis. The expression of B23 was analyzed and compared with that of proliferative cell nuclear antigen (PCNA) in these specimens.</p><p><b>RESULTS</b>RT-PCR and Western blot analysis showed that B23 expression in HCC was higher than that in adjacent liver tissue. Statistically significant difference in expressions of B23 and PCNA were also noted in the four groups studied (P < 0.01). B23 and PCNA expressions in HCC were higher than those in the other three groups (P < 0.01). There was also a statistically significant correlation between B23 and PCNA expressions amongst the four groups (r = 0.4769, P < 0.01). Besides, B23 expression in HCC correlated with pathologic tumor grading, serum alpha-fetal protein levels and cirrhotic status (P < 0.05).</p><p><b>CONCLUSIONS</b>B23 expression in HCC was significantly higher than that in liver tissues with non-malignant diseases. B23 may be used as a marker for neoplastic changes in liver cells and thus has potential clinicopathologic application.</p>

Over-expression in Escherichia coli and characterization of apolipoprotein AI / 生物工程学报

Apolipoprotein AI (apo AI), the major protein component of human high-density lipoprotein (HDL), is a single-chain polypeptide of 243 amino acids. Several epidemiological studies have shown that the plasma concentrations of HDL has the role of reverse cholesterol transport (RCT) and inversely correlated with the incidence of coronary artery disease. Because apo AI lacks post-translational modifications, it is convenient to express human apo AI in Escherichia coli expression system. However, there is a poor stability of the mRNA and the apo AI protein in E. coli, it is difficult to express mature apo AI in recombinant bacteria, moreover, even as a fusion protein, apo AI is still sensitive to degradation and can not be cleaved efficiently from the fusion tags. In contrast, proapolipoprotein AI (proapo AI, having an additional polypeptide containing the amino acids Arg-His-Phe-Trp-Gln-Gln at the amino-teminal of the mature protein) proved stable and undegraded in Escherichia coli, and therefore, in this research, an expression system of E. coli including a plasmid of P(R)P(L) tandem promoter was adapted to produce proapo AI. Furthermore, site-directed mutagenesis of the proapo AI cDNA was performed to generate a Clu8Asp mutation in the amino-terminal sequence of proapo AI which created an acid labile Asp-Pro peptide bond between amino acid 8 and 9, and permitted specific chemical cleavage to remove pro-peptide. After inducing with a shift of temperature, yields of recombinant proapo AI achieved about 40% of total cell protein and the recombinant proapo AI expressed proved as a form of inclusion body in cells, so protein need to renature. First of all, the protein was dissolved in buffer with denaturant, and renaturation was carried out on a hydrophobic interaction column (Phenyl Sepharose), ion-exchange chromatography and gel-filtration chromatography were then used to further purify the protein. The purified recombinant apo AI was detected by a set of tests including Western-blotting, Circular dichroism spectra and lipid-binding test, the results shown that recombinant apo AI has similar structural and lipid-binding properties identical to those of native plasma apo AI, which facilitates further research and application.