Investigation of organophosphorous insecticides residue in Chinese crude drugs / 中国中药杂志

<p><b>OBJECTIVE</b>To study eleven organophosphorus insecticides residuals in four kinds of Chinese crude drugs.</p><p><b>METHOD</b>The organophosphorus insecticides were extracted with dichloromethane and cleaned-up with a mixture of Celite 545-activated carbon. The extracts were analyzed by gas chromatography equipped with a flame photometric detector (FPD).</p><p><b>RESULT</b>Analysis of fortified Chinese crude drug showed that the average recoveries ranged from 77.5% -112.3% at three different levels, the RSDs were below 10% (n = 4). Trace organophosphorous pesticide residues were found in samples of Rhizoma Atractylodis Macrocephalae and Flos Chrysanthemi.</p><p><b>CONCLUSION</b>A method was established for determination multi-residues in Rhizma Atractylodis Macrocephalae, Radix Curcumae, Bulbus Fritillariae Thunbergii and Flos Chrysanthemi. It provides a method for the risk assessment of organophosphorous pesticide in Chinese crude drugs.</p>

The relationship between genetic polymorphism of metabolizing enzymes and the genetic susceptibility to lung cancer / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the gene polymorphism of metabolizing enzymes and the genetic susceptibility to lung cancer as well as to study the synergistic effects between smoking and the genes.</p><p><b>METHODS</b>A case-control study (case = 217, control = 200) was carried out to compare the frequent distribution of CYP1A1, 2E1, 2D6 and GSTM1 genotypes between the lung cancer group and the control group with a polymerase chain reaction-restriction fragment polymorphism (PCR-RFLP) method and to analyze the relationship between these genes and smoking.</p><p><b>RESULTS</b>GSTM1-null genotype frequency was 58.5% in the lung cancer group and 47.5% in the control group with significant difference (P = 0.02). The frequent distribution of CYP1A1, 2E1, 2D6 genotypes was not significantly different in the two groups (P > 0.05). Synergistic effects were found between smoking and GSTM1 but not between smoking and CYP1A1, 2E1, 2D6.</p><p><b>CONCLUSION</b>Smoking and GSTM1-null genotype seemed to be the risk factors of lung cancer. Those who carrying GSTM1-null genotype and smoking cigarettes were prone to suffer from lung cancer to become the high-risk population of the disease.</p>

Inhibitory effect of p53 with deletion of c-terminal 356 - 393 amino acids on malignant phenotype of human lung cancer cell line / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effect of extraneous p53 gene with deletion of c-terminal 356 - 393 amino acids on inhibition of malignant phenotype of human lung cancer cell line.</p><p><b>METHODS</b>Recombinant plasmid pEGFP-p53 (del) with codon deletion of c-terminal 37 amino acids from 393 to 356 region and pEGFP-p53 (wild type) were constructed. The human lung cancer cell line 801D served as a receipt cell had p53 deletion and mutation at 248 codon. 801D cells, having been transfected by pEGFP-p53 (wild type), pEGFP-p53 (del) or pEGFP, were selected by G418. Growing transfected cells were cloned respectively by method of dilution. Presence of extraneous gene was detected by PCR, their expression in cells was examined by fluorescence microscopy. Cloning efficiency was in vitro tested to examine the cellular proliferating ability. The xenograft in nude mice was performed and xenograft tumors were weighed one month later. Expression of GFP in tumor and transplanted cellular mass were detected by blot slices.</p><p><b>RESULTS</b>pEGFP-p53 (del)-801D, pEGFP-p53-801D and pEGFP-801D were established. Extraneous p53 gene and expression of GFP were found in pEGFP-p53 (del)-801D and pEGFP-p53-801D. Inhibitory rate of colony was 99.6% for pEGFP-p53 (del)-801D and 81.0% for pEGFP-p53-801D. Inhibition of malignant proliferation of extraneous p53 (del) was higher than that of p53 (wild type) (P < 0.01). Even when inhibition of malignant proliferation extraneous pEGFP-p53 (del) was obvious, 0.2% colonies were formed, extraneous p53 and expression of GFP were observed. Animal test showed that tumor on the nude mice was positive (4/4, 4/4) in the control group (801D and pEGFP-801D), but negative (0/4, 0/4) in the experiment group [pEGFP-p53 (del) 801D and pEGFP-p53 (wild type) 801D]. Expression of GFP in the cells of cellular mass transplanted by pEGFP-p53 (del) 801D or pEGFP-p53 (wild type) 801D was observed.</p><p><b>CONCLUSION</b>In vitro inhibitory effect of extraneous p53 gene with deletion of C-terminal 356 - 393 amino acids on malignant growth of lung cancer cell with p53 mutation or deletion at 248 codon is marked. Inhibitory action of p53 on malignant proliferation of cancer cells is heterogeneous.</p>