Study on genetic relationship of Swertia mileensis and its related species based on infrared spectroscopy combined with chemometrics / 中草药

Objective: Genetic reationships betwen Swertia mileensis and its relatives have been researched using Fourier transform infrared (FTIR) spectroscopy combined with chemometrics methods in order to provide a theoretical basis for the development and utilization of medicinal plant resources of genus Swertia. Methods: Infrared spectrum information of Swertia mileensis, Swertia cincta, Halenia elliptica, Swertiaion nervosa, Swertia punicea, and Swertia binchuanennsis was collected and used in this study. Original infrared spectra data were pretreated by these methods including automatic baseline correction, automatic smoothing, ordinate normalization, multiplicative scatter correction and second derivative, and analyzed by principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA). Results: Absorption area of relationship between Swertia mileensis and its relatives ranged from 900-400 cm-1, 1 310-900 cm-1, 1 500-1 310 cm-1, 1 800-1 500 cm-1, 2 800-3 000 cm-1, and 3 000-3 500 cm-1. Absorption peaks of the second derivative of fingerprint region in 400 to 1 000 cm-1 were distinct, and the absorption peaks as well as peak numbers, intensities and patterns among species were quite different. Analysis of preprocessed IR data showed that PCA analysis of six Swertia species was superior to PLS-DA analysis. The results of HCA analysis showed that Swertia mileensis was closely related to Swertia cincta and Swertia nervosa. Conclusion: FTIR spectroscopy combined with chemometrics method could discriminate different species of genus Swertia and display the closely genetic relationship of Swertia mileensis and its relatives, furthermore, this research would provide a fast and effective method for studying genetic relationship of genus Swertia.

Clinicopathological significance of altered metallothionein 2A expression in gastric cancer according to Lauren's classification / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Dysregulated metallothionein 2A (MT2A) has been implicated in carcinogenesis. The purpose of this study was to investigate the expression of MT2A in gastric cancer (GC) and its correlation with prognosis.</p><p><b>METHODS</b>Reverse transcription-polymerase chain reaction and real-time polymerase chain reaction were used to detect the mRNA expression of MT2A in 12 GC cell lines, normal gastric epithelial GES-1 cells, and 36 GC and adjacent normal tissues. MT2A protein expression was determined in 258 GC tissues and 171 adjacent normal tissues by immunohistochemistry.</p><p><b>RESULTS</b>MT2A mRNA expression was lower in GC cells and primary tumors than in GES-1 cells and adjacent normal tissues, respectively. High protein expression of MT2A was present in 130 of 171 normal tissues (76.0%) and in 56 of 258 GC tissues (21.7%; P < 0.001). MT2A protein expression was higher in well/moderately differentiated GC (22/54; 40.7%) than in poorly differentiated GC (34/204; 16.7%; P < 0.001). Moreover, the protein expression of MT2A was lower in diffuse-type GC (6/82; 7.3%) than in intestinal-type GC (50/176; 28.4%; P = 0.0001). Importantly, MT2A expression was an independent prognostic factor for GC, and decreased MT2A expression was associated with poor clinical outcome (P < 0.001). The expression status of MT2A could predict prognosis in intestinal and diffuse-type GCs.</p><p><b>CONCLUSION</b>Expression status of MT2A might be a useful prognostic biomarker for GC, especially when used in combination with Lauren's classification.</p>

Soluble expression of active human beta-defensin-3 in Escherichia coli and its effects on the growth of host cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human beta-defensin-3 (HBD(3)) is an epithelial peptide that has been demonstrated to have a salt-insensitive broad spectrum of potent antimicrobial activity. Expressing antimicrobial peptides in Escherichia coli (E. coli) is very difficult for it can result in death of the bacterial host cells. Our aim was to establish a prokaryotic system expressing soluble HBD(3) protein and demonstrate the antimicrobial activity of the expressed protein. We then studied whether the host cells would activate the suicide pathways.</p><p><b>METHODS</b>We first cloned the complementary DNA coding for the mature chain of HBD(3), inserted it into the vector PGEX-KG then transformed E. coli BL21 (DE3) with the appropriate recombinant plasmid. After induction with 0.5 mmol/L isopropyl-1-thio-beta-D-galactopyranoside (IPTG) the transformed E. coli produced a recombinant glutathione S-transferase and HBD(3) (GST-HBD(3)) fusion protein. The fusion protein was treated with thrombin to produce pure HBD(3) protein then the antimicrobial activity of HBD(3) was evaluated in a liquid microdilution assay.</p><p><b>RESULTS</b>The fusion protein GST-HBD(3) was efficiently cleaved by thrombin and yielded HBD(3) that had anti-staphylococcus aureus activity with a minimal inhibitory concentration level of 12.5 microg/ml. The E. coli strain expressing the recombinant protein did not grow slower than the empty vector strain.</p><p><b>CONCLUSION</b>Active HBD(3) in E. coli by expressing the recombinant protein GST-HBD(3) could be produced, and suicide did not occur in the E. coli strain expressing the recombinant protein.</p>

Prognostic significance of clinicopathologic parameters in gastrointestinal stromal tumor: a study of 156 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To evaluate the prognostic significance of various clinicopathologic parameters in gastrointestinal stromal tumor (GIST), and to study the frequency of c-kit exon 11 mutations in this tumor.</p><p><b>METHODS</b>One hundred and fifty-six cases of gastric or small intestinal GIST were retrieved from the archival files of the Department of Pathology, Chinese PLA General Hospital. The clinical features, site of occurrence, tumor diameter, mitotic index, coagulative tumor necrosis, and risk grade were studied and analyzed statistically. Tumor DNA was extracted and c-kit exon 11 was amplified. Upon detection by denaturing high-performance liquid chromatography, the amplified exon 11 was sequenced.</p><p><b>RESULTS</b>For the 83 cases of gastric GIST studied, the mean age of patients was 55.4 years. Follow-up information was available in 62 cases, with 17 cases having local recurrence or distant metastasis. The 5-year survival rate was 66.5% +/- 17.1%. For the 73 cases of small intestinal GIST studied, the mean age of patients was 50.6 years. Follow-up information was available in 43 cases, with 22 cases having local recurrence or distant metastasis. The 5-year survival rate was 61.8% +/- 18.3%. In general, for gastric GIST, age younger than 50 years (P = 0.046), advanced clinical stage (P = 0.0001), large tumor size (P = 0.0001), high mitotic index (P = 0.0001), presence of coagulative tumor necrosis (P = 0.0001), and high risk grade (P = 0.004) were associated with lower survival rate. COX hazard proportional model revealed that advanced clinical stage (P = 0.001), large tumor size (P = 0.001), high mitotic index (P = 0.002) and high risk grade (P = 0.018) indicated worse prognosi. For small intestinal GIST, advanced clinical stage (P = 0.010) and presence of coagulative tumor necrosis (P = 0.036) were associated with lower survival rate. Advanced clinical stage was an independent prognostic factor. A total of 25 cases harbored c-kit mutations. The frequency of c-kit mutations was 32% and 22.5% for gastric and small intestinal GIST respectively. For gastric GIST, c-kit mutations occurred mainly in patients older than 50 years. In contrast, c-kit mutations in small intestinal GIST occurred in the age group of 40 to 49 years.</p><p><b>CONCLUSIONS</b>For gastric GIST, advanced clinical stage, tumor diameter, mitotic index and risk grade are the main prognostic indicators. For small intestinal GIST, advanced clinical stage and presence of coagulative tumor necrosis indicate poor prognosis. In general, small intestinal GIST is more frequently associated with metastasis and tumor relapse than gastric GIST. The occurrence of c-kit mutations also correlates with age of patients.</p>