2009 Vol. 22, No. 1

Select articles
Gender Differences in Acute Cadmium-Induced Systemic Inflammation in Rats
2009, 22(1): 1-7.
Objective To examine the presence of gender differences in pro-inflammatory potential of cadmium in rats by comparing systemic inflammatory response to acute cadmium intoxication in animals of the two sexes. Methods Basic aspects of this response were evaluated, including plasma levels of inflammatory cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6) and of major rat acute phase protein alpha 2-macroglobulin (alpha2-M), as soluble indicators of inflammation, and the number and activity of peripheral blood leukocytes, as cellular indicators of inflammation. Results Differential increases of IL-6 and alpha 2-M (higher in males than in females) in peripheral blood cell counts and types (leukocytosis and shift in the ratio of granulocytes to lymphocytes more pronounced in males vs females) and in levels of neutrophil priming (higher in males vs females) were noted. Conclusion The data document a more intense inflammatory response to cadmium administration in males. The sex differences in inflammatory effects of cadmium might be taken into consideration in studying the toxicity of this heavy metal.
Frame Work of Data Envelopment Analysis——A Model to Evaluate the Environmental Efficiency of China's Industrial Sectors
2009, 22(1): 8-13.
Objective To evaluate the environmental and technical efficiencies of China's industrial sectors and provide appropriate advice for policy makers in the context of rapid economic growth and concurrent serious environmental damages caused by industrial pollutants. Methods A data of envelopment analysis (DEA) framework crediting both reduction of pollution outputs and expansion of good outputs was designed as a model to compute environmental efficiency of China's regional industrial systems. Results As shown by the geometric mean of environmental efficiency, if other inputs were made constant and good outputs were not to be improved, the air pollution outputs would have the potential to be decreased by about 60% in the whole China. Conclusion Both environmental and technical efficiencies have the potential to be greatly improved in China, which may provide some advice for policy-makers.
MicroRNA Expression Profiles and MiR-10a Target in Anti-benzo[a] pyrene-7, 8-diol-9, 10-epoxide-transformed Human 16HBE Cells
2009, 22(1): 14-21.
Objective To screen miRNA profiles of malignantly transformed human bronchial epithelial cells, 16HBE-T, induced by anti-benzo[a]pyrene-trans-7,8-diol-9,10-epoxide (anti-BPDE), and to analyze putative miR-10a targets in 16HBE-T. Methods A novel microarray platform was employed to screen miRNA profiles of 16HBE-T cells transformed by anti-BPDE. Microarray data for miR-10a and miR-320 were validated using quantitative real time polymerase chain reaction (QRT-PCR). The expression of a putative target for miR-10a, HOXA1, was analyzed by reverse transcription polymerase chain reaction (RT-PCR) and QRT-PCR. Results In comparison with the vehicle-treated cells (16HBE-N), 16HBE-T exhibited differential expression of 54 miRNAs, in which, 45 were over-expressed and 9 were down-regulated. The five most highly expressed miRNAs were miR-494, miR-320, miR-498, miR-129, and miR-106a. The lowest expressed miRNAs were miR-10a, miR-493-Sp, and miR-363*. Three members of miR-17-92 cluster, miR-17-Sp, miR-20a, and miR-92, showed significantly higher abundance in 16BHE-T as miR-21, miR-141, miR-27a, miR-27b, miR-16 and miRNAs of the let-7 family. The putative target for miR-10a, HOXA1 mRNA was up-regulated 3-9-fold in 16HBE-T, as compared with 16HBE-N. Conclusion The findings of the study provide information on differentially expressed miRNA in malignant 16HBE-T, and also suggest a potential role of these miRNAs in cell transformation induced by anti-BPDE. HOXA1 is similarly up-regulated, suggesting that miR-10a is associated with the process of HOXA 1-mediated transformation.
Large-scale Purification and Acute Toxicity of Hygromycin B Phosphotransferase
2009, 22(1): 22-27.
Objective To provide the acute toxicity data of hygromycin B phosphotransferase (HPT) using recombinant protein purified from E. coli. Methods Recombinant HPT protein was expressed and purified from E. coli. To exclude the potential adverse effect of bacteria protein in recombinant HPT protein, bacterial control plasmid was constructed, and bacteria control protein was extracted and prepared as recombinant HPT protein. One hundred mice, randomly assigned to 5 groups, were administrated 10 g/kg, 5 g/kg, or 1 g/kg body weight of HPT or 5 g/kg body weight of bacterial control protein or phosphate-buffered saline (PBS) respectively by oral gavage. Results All animals survived with no significant change in body weight gain throughout the study. Macroscopic necropsy examination on day 15 revealed no gross pathological lesions in any of the animals. The maximum tolerated dose (MTD) of HPT was 10 g/kg body weight in mice and could be regarded as nontoxic. Conclusion HPT protein does not have any safety problems to human health.
Determination of Residual Acrylamide in Medical Polyacrylamide Hydrogel by High Performance Liquid Chromatography tandem Mass Spectroscopy
2009, 22(1): 28-31.
Objective To determine residual acrylamide in medical polyacrylamide hydrogel by high performance liquid chromatography tandem mass spectroscopy (HPLC-MS). Methods After 13C3 labeled acrylamide was added, the sample was extracted with water and then cleaned up with ExtrelutTM 20. The polyaerylamide hydrogel sample and 20 clinical cases were analyzed by HPLC-MS/MS and isotope dilution quantifying technique in selected reaction monitoring (SRM) mode. Results Acrylamide was separated from polyacrylamide hydrogel. The concentration of acrylamide in polyacrylamide hydrogel ranged from 3.9×109 to 3.1×108g/L in the 20 clinical cases. The peak area was favorable linear and the range was up to 3 000 μg/L. The recovery rate was 103.1% with a relative standard deviation (RSD) of 6.20%, when the mark level was 50 μg/L. Conclusion HPLC-MS is a rapid, accurate, and sensitive method for the determination of residual acrylamide in medical polyacrylamide hydrogel.
Curcumin, a Potential Inhibitor of Up-regulation of TNF-alpha and IL-6 Induced by Palmitate in 3T3-L1 Adipocytes through NF-kappaB and JNK Pathway
2009, 22(1): 32-39.
Objective To investigate the attenuating effect of curcumin, an anti-inflammatory compound derived from dietary spice turmeric (Curcuma longa) on the pro-inflammatory insulin-resistant state in 3T3-L1 adipocytes. Methods Glucose uptake rate was determined with the [3H] 2-deoxyglucose uptake method. Expressions of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were measured by quantitative RT-PCR analysis and ELISA. Nuclear transcription factor kappaB p65 (NF-κB p65) and mitogen-activated protein kinase (MAPKs) were detected by Western blot assay. Results The basal glucose uptake was not altered, and curcumin increased the insulin-stimulated glucose uptake in 3T3-L1 cells. Curcumin suppressed the transcription and secretion of TNF-α and IL-6 induced by palmitate in a concentration-dependent manner. Palmitate induced nuclear translocation of NF-kB. The activities of Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase1/2 (ERK1/2) and p38MAPK decreased in the presence of curcumin. Moreover, pretreatment with SP600125 (inhibitor of JNK) instead of PD98059 or SB203580 (inhibitor of ERK 1/2 or p38MAPK, respectively) decreased the up-regulation of TNF-α induced by palmitate. Conclusion Curcumin reverses palmitate-induced insulin resistance state in 3T3-L1 adipocytes through the NF-kB and JNK pathway.
Effects of 3,4-Dichloroaniline on Testicle Enzymes as Biological Markers in Rats
2009, 22(1): 40-43.
Objective To investigate the effects of 3,4-dichlomaniline (3,4-DCA) on activities of testicle enzymes as biological markers in rats. Methods Fifty male rats were randomly divided into 5 groups (n=10). One group was left untreated and used as a solvent control (administered orally by corn oil), while the other 4 groups were treated with 3, 4-DCA. Corn oil was used as a solvent, and 3,4-DCA was diluted into tested concentrations (39, 81, 170, and 357 mg/kg). All the groups orally administered 3,4-DCA or corn oil, once a day for 4 weeks. The testicle tissue was homogenized in a 0.1 mol/L potassium phosphate buffer (0.1 mol/L, pH 7.2). The crude homogenate was centrifuged at 6000 rpm for 5 rain at 4 ℃. The supematant obtained was used as an enzyme extract for determination of the enzyme activities. Results Compared with the control, the activities of ALP, ACE and SDH were increased significantly at a lower level of 3,4-DCA, and decreased at a higher level of 3, 4-DCA, whreas the activities of LDH, LDH-X, and G6PDH were inhibited significantly with the increased 3,4-DCA concentration. Organ coefficient "organ weight/total body weight × 100" of testis, liver, and spleen increased significantly with the increased 3,4-DCA concentration. These results suggest that 3,4-DCA toxicity to the male reproductive system was associated with the activities of testicular enzymes which are the sensitive biochemical endpoints reflecting 3,4-DCA toxicity to the male reproductive system. Conclusion 3,4-DCA has toxicity to the reproductive system in male rats.
Relationship between Levels of Testosterone and Cortisol in Saliva and Aggressive Behaviors of Adolescents
2009, 22(1): 44-49.
Objective To explore the endocfinal factors which influence the aggressive behavior of adolescents. Methods The levels of cortisol (CORT), testosterone (T), prolactin (PRL), and growth hormone (GH) in saliva from 20 aggressive students and 20 non-aggressive control students were measured by radioimmunoassay (RIA). The students were matched for their gender, age, grade, stage of pubertal development, and economic status of their families. Results The salivary T levels were 22.20±14.50 pg/mL and 19.54±12.52 pg/mL in aggressive male and female students, 13.20±6.85 pg/mL and 5.24±3.03 pg/mL in non-aggressive male and female students (P<0.05). The male aggressive students had a lower level of CORT in saliva than non-aggressive male students (P<0.05). There were no significant differences in the salivary levels of PRL or GH between the aggressive and non-aggressive groups. Correlation analysis revealed a negative relationship in male students between the salivary CORT levels and the aggression factor scores of the child behavior checklist (CBCL). In addition, the data also showed a positive relationship between the salivary T levels and the aggression factor .scores of CBCL in female students. Multiple linear regression analysis showed that the salivary CORT level was an independent predictive factor for aggressive behaviors in adolescent boys. The higher the CORT level, the less aggressive the boys were. Conclusion CORT and T levels may play a certain role in adolescent aggressive behaviors.
Protection of PC12 Cells against Superoxide-induced Damage by Isoflavonoids from Astragalus mongholicus
2009, 22(1): 50-54.
Objective To further investigate the neuroprotective effects of five isoflavonoids from Astragalus mongholicus on xanthine (XA)/xanthine oxidase (XO)-induced injury to PC12 cells. Methods PC12 cells were damaged by XA/XO. The activities of antioxidant enzymes, MTT, LDH, and GSH assays were used to evaluate the protection of these five isoflavonoids. Contentsof Bcl-2 family proteins were determined with flow cytometry. Results Among the five isoflavonoids including formononetin, ononin, 9, 10-dimethoxypterocarpan-3-O-β-D-glucoside, calycosin and calycosin-7-O-glucoside, calycosin and calycosin-7-O-glucoside were found to inhibit XA/XO-induced injury to PCI2 cells. Their EC50 values of formononetin and calycosin were 0.05 μg/mL. Moreover, treatment with these three isoflavonoids prevented a decrease in the activities of antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), while formononetin and calycosin could prevent a significant deletion of GSH. In addition, only calycosin and calycosin-7-O-glucoside were shown to inhibit XO activity in cell-free system, with an approximate IC50 value of 10 μg/mL and 50 μg/mL. Formononetin and calycosin had no significant influence on Bcl-2 or Bax protein contents. Conclusion Neuroprotection of formononetin, calycosin and calycosin-7-O-glucoside may be mediated by increasing endogenous antioxidants, rather by inhibiting XO activities or by scavenging free radicals.
Molecular Epidemiological Study on Prevalence of Human Papillomaviruses in Patients with Common Warts in Beijing Area
2009, 22(1): 55-61.
Objective To study the circulation, distribution, and genomic diversity of HPVs in common warts in Beijing area of China. Methods Forty eight patients with pathologically diagnosed common warts were screened for the presence of HPV with HPV type-specific PCR and direct .sequencing analysis. The genomic diversity of HPVs prevalent in Chinese patients was analyzed based on LCR. Results Forty one (85.5%) samples were positive for HPV DNA, 13(31.7%)-HPV-57, 12(29.3%)-HPV-1 a, 7(17%)-HPV-27 and 5(12.2%)-HPV-2a. Four cases were infected with two different HPV types, two (4.9%) with HPV-1a and HPV-27, one (2.4%) with HPV-1 and HPV-57 and one (2.4%) with HPV-27 and HPV-57. In contrast to the prevalence of single strain of novel HPV-57 variant and HPV-1 prototype, two HPV-2 and three HPV-27 novel variants were found to circulate in Beijing. Conclusion HPV-1, -2, -27 and -57 are predominantly prevalent in patients with common warts in Beijing.
Establishment of Hypoglycemic Agent Screening Method Based on Human Glucokinase
2009, 22(1): 62-69.
Objective To establish a reliable platform for screening glucokinase activators (GKAs) in vitro. Methods Pancreatic glucokinase (PGK) protein expressed in a prokaryotic expression system as a histidine-tagged fusion protein from Homo sapiens was produced. Then, response surface methodology (RSM) was used to optimize the microplate-based GKA screening platform. In the first step of optimization with Plackett-Burman design (PBD), initial pH, reaction time and MgC12were found to be important factors affecting the activity ratio of GKA (RO-28-1675) significantly. In the second step, a 23 full factorial central composite design (CCD) and RSM were applied to the optimal condition determination of each significant variable. A second-order polynomial was determined by a multiple regression analysis of the experimental data. Results The following optimal values for the critical factors were obtained: initial pH 0 (7.0), reaction time-0.63 (13.7 min) and MgCl2 0.11 (2.11mmol/L) with a predicted value of the maximum activity ratio of 34.1%. Conclusion Under the optimal conditions, the practical activity ratio is 34.8%. The determination coefficient (R2) is 0.9442, ensuring adequate credibility of the model.LLAE3, extracted from Folium nelumbinis in our laboratory, has prominently activated effects on PGK.
Effects of Chronic Administration of Melatonin on Spatial Learning Ability and Long-term Potentiation in Lead-exposed and Control Rats
2009, 22(1): 70-75.
Objective To explore the changes in spatial learning performance and long-term potentiation (LTP) which is recognized as a component of the cellular basis of learning and memory in normal and lead-exposed rats after administration of melatonin (MT) for two months. Methods Experiment was performed in adult male Wistar rats (12 controls, 12 exposed to melatonin treatment, 10 exposed to lead and 10 exposed to lead and melatonin treatment). The lead-exposed rats received 0.2% lead acetate solution from their birth day while the control rats drank tap water. Melatonin (3 mg/kg) or vehicle was administered to the control and lead-exposed rats from the time of their weaning by gastric garage each day for 60 days, depending on their groups. At the age of 81-90 days, all the animals were subjected to Morris water maze test and then used for extracellular recording of LTP in the dentate gyrus (DG) area of the hippocampus in vivo. Results Low dose of melatonin given from weaning for two months impaired LTP in the DG area of hippocampus and induced learning and memory deficit in the control rats. When melatonin was administered over a prolonged period to the lead-exposed rats, it exacerbated LTP impairment, learning and memory deficit induced by lead. Conclusion Melatonin is not suitable for normal and lead-exposed children.
Potential Mechanisms Involved in Ceramide-induced Apoptosis in Human Colon Cancer HT29 Cells
2009, 22(1): 76-85.
Objective To investigate the potential mechanisms of cell death after the treatment with ceramide. Methods MTT assay,DNA ladder, reporter assay, FACS and Western blot assay were employed to investigate the potential mechanisms of cell death after the treatment with C2-ceramide. Results A short-time treatment with C2-ceramide induced cell death, which was associated with p38 MAP kinase activation, but had no links with typical caspase activation or PARP degradation. Rather than caspase inhibitor, Inhibitor of p38 MAP kinase blocked cell death induced by a short-time treatment with ceramide (<12 h). However, inhibition of p38 MAP kinase could not block cell death induced by a prolonged treatment with ceramide (>12 h). Moreover, incubation of cells with ceramide for a long time (>12 h) increased subGl, but reduced S phase accompanied by caspase-dependent and caspase-independent changes including NFκB activation. Conclusion Ceramide-induced cell apoptosis involves both caspase-dependent and -independent signaling pathway. Caspase-independent cell death occurring in a relatively early stage, which is mediated via p38 MAP kinase, can progress into a stage involving both caspase-dependent and -independent mechanisms accompanied by cell signaling of MAPKs and NFκB.
Biomedical and Environmental Sciences Information For Authors
2009, 22(1): 封3-封4.