Seventy Years of Progress of Food Safety in China / 中华疾病控制杂志

@# Food safety has become the essential issue for national well-being and the people’s livelihood. Since the founding the People’s Republic of China (PRC), food safety has made great progress in all aspects of laws and regulations, surveillance and supervision. Currently, the overall status of food safety in China is moving towards the upside, but still tough and facing great challenges. This paper reviews the changes and progress in laws and regulations, surveillance and management, science and technology in food safety since the founding the PRC, as well as proposes several current challenges, to provide some thoughts to wrap up the past and move forward to improve the food safety in China.

Acute and 28-day sub-acute oral toxicity evaluation of two dietary bamboo charcoal powders in Sprague-Dawley rats / 华中科技大学学报（医学）（英德文版）

No data were available on the acute oral toxicity, short-term oral toxicity of vegetable carbon in animals. This study was designed to evaluate the safety of two commercially available dietary bamboo charcoal powders (BCP1 and BCP2). The size distribution of the two powders was determined by a Mastersizer 2000 laser particle size analyzer prior to the in vivo safety studies. For the acute toxicity study, a single dose of 11.24 g/kg body weight of BCP1 and BCP2 was given once orally to healthy Sprague-Dawley (SD) rats. Mortality and clinical symptoms were observed and recorded for the first 30 min after treatment, at 4 h post-administration, and then at least once daily for 14 days after administration. In the repeated dose 28-day oral toxicity study, BCP1 and BCP2 were administered orally at doses of 2.81, 5.62, and 11.24 g/kg body weight for 28 days to SD rats. Animals were sacrificed and organs and blood samples were analyzed. Results showed that both BCP1 and BCP2 were micro-sized and various in size. In the acute toxicity and the repeated dose 28-day oral toxicity studies, BCP caused neither mortality nor visible signs of toxicity in rats. No significant differences were found in the relative organ weights or in biochemical parameters in BCP treated groups compared to a control group. No treatment-related histological changes were observed in the organs of these animals. Based on these data, it is concluded that the median lethal dose (LD50) of BCP for both male and female rats is more than 11. 24 g/kg body weight and the no-observed-adverse-effect level (NOAEL) is >11.24 g/kg body weight for 28 days.

Acute and 28-day sub-acute oral toxicity evaluation of two dietary bamboo charcoal powders in Sprague-Dawley rats / 华中科技大学学报（医学）（英德文版）

No data were available on the acute oral toxicity, short-term oral toxicity of vegetable carbon in animals. This study was designed to evaluate the safety of two commercially available dietary bamboo charcoal powders (BCP1 and BCP2). The size distribution of the two powders was determined by a Mastersizer 2000 laser particle size analyzer prior to the in vivo safety studies. For the acute toxicity study, a single dose of 11.24 g/kg body weight of BCP1 and BCP2 was given once orally to healthy Sprague-Dawley (SD) rats. Mortality and clinical symptoms were observed and recorded for the first 30 min after treatment, at 4 h post-administration, and then at least once daily for 14 days after administration. In the repeated dose 28-day oral toxicity study, BCP1 and BCP2 were administered orally at doses of 2.81, 5.62, and 11.24 g/kg body weight for 28 days to SD rats. Animals were sacrificed and organs and blood samples were analyzed. Results showed that both BCP1 and BCP2 were micro-sized and various in size. In the acute toxicity and the repeated dose 28-day oral toxicity studies, BCP caused neither mortality nor visible signs of toxicity in rats. No significant differences were found in the relative organ weights or in biochemical parameters in BCP treated groups compared to a control group. No treatment-related histological changes were observed in the organs of these animals. Based on these data, it is concluded that the median lethal dose (LD50) of BCP for both male and female rats is more than 11.24 g/kg body weight and the no-observed-adverse-effect level (NOAEL) is >11.24 g/kg body weight for 28 days.

Non-modified magnetic beads coupled with multiple real-time PCR for detection and quantification of mycotoxigenic fungi in paprika samples / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for detecting 3 common toxigenic molds (Aspergillus, Penicillium, and Fusarium) based on non-modified magnetic beads coupled with multiple real-time PCR (NMB-multiple qPCR).</p><p><b>METHODS</b>The primers and genus-specific probes were designed based on the rDNA sequences to develop a multiple real-time PCR using non-modified magnetic bead to enrichment of fungal spores. The sensitivity, specificity and repeatability of this assay were evaluated.</p><p><b>RESULTS</b>The detection limit of this assay for spiked samples was 10(4) CFU/g, demonstrating a 10-fold greater detection sensitivity of this assay than that of real-time PCR. The NMB-multiple qPCR assay also showed good specificity and reproducibility and yielded comparable results with those by traditional colony counting method for spiked samples (P>0.05).</p><p><b>CONCLUSION</b>NMB-multiple qPCR assay we established allows rapid and sensitive detection of common mycotoxigenic fungi in paprika.</p>

Toxic effects of atrazine on reproductive system of male rats / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>This study was designed to evaluate the toxic effects of Atrazine (ATZ) on the reproductive system of male rats.</p><p><b>METHODS</b>Male Sprague-Dawley rats were exposed to ATZ by gavage at dosages of 0, 38.5, 77, and 154 mg/kg bw/day for 30 d. The toxic effects of ATZ to rats were assessed through histopathologcal observation, spermatozoa quality evaluation, testicular marker enzyme indicators, antioxidant capacity and reproductive hormone levels.</p><p><b>RESULTS</b>Significant adverse effects on reproductive system were observed in rats exposed to ATZ at different dosages compared with 0 mg/kg group, including an irregular and disordered arrangement of the seminiferous epithelium in 154 mg/kg group; a decreased spermatozoa number and an increased spermatozoa abnormality rate in 77 and 154 mg/kg groups; decreased levels of acid phosphatase (ACP), alkaline phosphatase (AKP), lactic dehydrogenase (LDH), and succinate dehydrogenase (SDH) with the increasing of ATZ concentration; a decreased level of total antioxidant capacity (TAC) in a dose-dependent manner, and a decreased reduced glutathione (GSH) level and an increased malondialdehyde (MDA) content in 154 mg/kg group; and decreased serum levels of testosterone (T) and inhibin-B (INH-B) and an increased serum level of follicle stimulating hormone (FSH) in 77 and 154 mg/kg groups, and an increased serum level of luteinizing hormone (LH) in 154 mg/kg group.</p><p><b>CONCLUSION</b>These results suggested that relatively high doses of ATZ could exert reproductive toxicity of male rats.</p>

Investigation on levels of polybrominated diphenyl ethers in retail fish and egg products in Shenzhen / 中华预防医学杂志

<p><b>OBJECTIVE</b>To reveal the levels and distribution of polybrominated diphenyl ethers (PBDEs) in fish and egg products at retail in Shenzhen, and to evaluate the local people's exposure to PBDEs from these food.</p><p><b>METHODS</b>27 fish and egg samples were collected from supermarket and farmer's market in Shenzhen during August and October in 2008. According to the guideline of USEPA1614 method, the accelerated solvent extraction (ASE) technology was used for the extraction of PBDEs from fish and egg samples. After a series of purification processes including treatments of FMS column chromatography, acidic silica gel, silica gel and Al2O3 column, the levels of eight PBDEs congeners in the samples were determined by isotope dilution high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) method.</p><p><b>RESULTS</b>When BDE-209 was not taken into account, the median concentrations of ΣPBDEs in fish products was 914.7 pg/g wet weight, among which the datas for fresh water fish and sea fish were 328.2 and 1108.8 pg/g wet weight, respectively, showing a statistical significant difference (P < 0.05). BDE-47 was the predominant congener in fresh water fish and sea fish by a contribution proportion of 61% and 57%, respectively. The median concentrations of ΣPBDEs in egg products were 99.8 pg/g wet weight and the predominant congeners are BDE-47 and BDE-99, with a contribution proportion above 70%. BDE-209 was not detected in fresh water fish and the median concentration in sea fish and egg products are 243.7 and 472.6 pg/g wet weight, respectively, which caused the predominant congener changed to BDE-209 in egg products when BDE-209 was take into account. The median dietary intake of PBDEs from fish and egg products among local residents in Shenzhen was estimated as 102 ng/d.</p><p><b>CONCLUSION</b>The level of ΣPBDEs in fish and egg products in Shenzhen is relatively high. The characteristics of PBDEs pollution are quite different between fish and egg products. The level of daily dietary intake of PBDEs from fish and egg products among local residents in Shenzhen is also relatively high.</p>

The levels of dioxin in 60 human breast milk samples and the exposure risk factor analysis in Shenzhen / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD-Fs) in human breast milk of the mothers who lived in non-directly persistent organic pollutants (POPs) polluted area in Shenzhen, and the correlation of exposure risk factor was analyzed.</p><p><b>METHODS</b>From July to November in 2007, 60 primiparas by vaginal delivery after parturition 3 weeks to 2 months were sampled for breast milk who aged from 20 - 34 years old and has lived in Shenzhen non-directly POPs polluted areas over 5 years. PCDD-Fs were extracted from the frozen-dried samples with accelerated solvent extraction (ASE), cleaned up by fluid management system (FMS) and quantified by high-resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS) using isotope dilution methodology. TEQ were calculated. The correlation relationship among infant's birth weight and length, participatory's dietary, age, inhabitation period, environment and the body burden of PCDD-Fs in mother was statistically analyzed by SPSS 13.0.</p><p><b>RESULTS</b>The participants aged from 20 - 34 years old (28 years on average) and lived in Shenzhen for 5 - 29 years (10 years on average). The concentration of PCDD-Fs in 60 breast milk samples were 26.957 143 - 669.583 333 pg/g fat (mean: 7.224 817 pg/g fat, median: 84.176 062 pg/g fat), and TEQ-PCDD-Fs in samples were 2.420 793 - 29.014 277 pg/g fat (mean: 8.645 992 pg/g fat, median: 7.751 804 pg/g fat). 2, 3, 4, 7, 8-PeCDF, 1, 2, 3, 7, 8-PeCDD, 2, 3, 7, 8-TCDD were the dominant contributors to the total TEQ, which were 3.691 654 pg/g fat (42.689 378%), 2.478 315 pg/g fat (28.652 356%), and 0.980 995 pg/g fat (11.343 995%) respectively. Significant positive correlations were found among age (r = 0.26, P < 0.05), inhabitation period (r = 0.49, P < 0.05), the consumption of fish (r = 0.37, P < 0.05) and the concentrations of TEQ-PCDD-Fs in the study.</p><p><b>CONCLUSION</b>The levels of dioxin chemicals in the breast milk samples in non-directly POPs polluted areas of Shenzhen are high. Significant positive correlations were found among age, inhabitation period, the consumption of fish and the concentration of PCDD-Fs.</p>

Characterization of Salmonella enterica serotype typhimurium from outpatients of 28 hospitals in Henan province in 2006 / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To characterize the diarrheal patients with Salmonella typhimurium (S. typhimurium) infections and to set up the first baseline for S. typhimurium pulsed-field gel electrophoresis (PFGE) patterns in Henan province, thus laying a foundation for comprehensive surveillance of Salmonella in human as well as foods.</p><p><b>METHODS</b>S. typhimurium isolates recovered from outpatients with diarrhea in Henan province from May to October of 2006 were characterized. Antimicrobial susceptibility tests of 8 antimicrobial agents and PFGE were carried out to analyze the S. typhimurium isolates.</p><p><b>RESULTS</b>Twenty-four (0.9%) S. typhimurium isolates were identified from 2661 stool specimens of diarrheal cases. Eighty-eight percent of isolates showed resistance to at least one antimicrobial agent. The resistance to chloramphenicol (79%) was most common. Fifty-eight percent of isolates were resistant to ciprofloxacin. All the 14 ciprofloxacin-resistant isolates were resistant to more than five antimicrobial agents. Thirty-three percent of S. typhimurium isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R-type ACSSuT). Eight antimicrobia-resistant phenotypes were found among the 24 isolates in 16 PFGE patterns.</p><p><b>CONCLUSION</b>The rate of multidrug-resistant S. typhimurium is relatively high in S. typhimurium PFGE patterns of Henan province. Multidrug-resistant S. typhimurium should be considered a public health threat.</p>

Gene expression profile of isoniazid liver-injured rat using cDNA microarray / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the changes of gene expression profile of rat liver tissue by cDNA microarrays.</p><p><b>METHODS</b>Twenty Wistar rats in control group (n = 10) and isoniazid (INH) group (n = 10) were orally administrated with normal saline and 400 mg/kg INH for 14 days, respectively. The differentially expressed genes significantly correlated with liver injury were screened and analyzed. The mechanisms of liver injury caused by INH were specifically analyzed at level of gene expression based on the biological functions of those differentially expressed genes.</p><p><b>RESULTS</b>Thirty-seven differentially expressed genes were found in the rats administrated with INH. Among them, 25 genes were up-regulated, while the other 12 genes were down-regulated. These differentially expressed genes were functionally related to the changes of CYP450-related genes, fatty acid metabolism, and protein metabolism.</p><p><b>CONCLUSION</b>INH can cause the remarkable changes of the gene expression profiles in rat liver cells, which is important for further elucidating the mechanisms of liver injury caused by INH.</p>

Effects of amitrole on thyroid hormone-associated gene transcription in FRTL-5 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of amitrole on the transcription of thyroglobulin (tg), thyroid peroxidase (tpo), Na(+)/I- symporter (nis), Na(+)/I- symporter (nis), thyroid-stimulating hormone receptor (tshr), thyroid transcription factor 1 (ttf-1) and paired-domain protein-8 (pax-8) genes in FRTL-5 cells and investigate the mechanism of amitrole for intervening in thyroid hormone activity.</p><p><b>METHODS</b>FRTL-5 cells were treated with amitrole at 0.001, 0.01 and 0.1 mg/ml for 24 h, respectively, after which the cells were collected for extraction of the total RNA. RT-PCR was used to examine the effects of amitrole on the transcription of tg, tpo, nis, tshr, pax-8 and ttf-1 genes in FRTL-5 cells.</p><p><b>RESULTS</b>Amitrole significantly induced tg gene transcription at all the doses, but produced no obvious effects on tpo and nis gene transcription. At the concentration of 0.1 mg/ml, amitrole significantly reduced pax-8 and tshr gene transcription but increased ttf-1 gene transcription.</p><p><b>CONCLUSION</b>The effects of amitrole on thyroid hormone activity may be related with its actions on tg, ttf-1, tshr and pax-8 gene transcription.</p>

Preparation and evaluation of novel solid chlorine dioxide-based disinfectant powder in single-pack / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To prepare and evaluate novel chlorine dioxide-based disinfectant powder in single-pack that is more convenient for use and transportation.</p><p><b>METHODS</b>Orthogonal experiment was performed to determine the recipe of the disinfectant powder. Stability test, suspension quantitative bactericidal test, simulation field trial, and animal toxicity test were carried out to observe its bactericidal and toxicological effects.</p><p><b>RESULTS</b>The orthogonal experiment showed that the type of water solution had no effect on the disinfectant powder and the best ratio of sodium chlorite to solid acid was 1:3. Ten grams of the disinfectant powder was fully dissolved in 20 mL water for 2 min, and diluted to 500 mL in water. After 5-10 min, the concentration of chlorine dioxide (ClO2) solution was 266 mg/L to 276 mg/L. After stored at 54 degrees C for 14 d, the average concentration of ClO2 was decreased by 5.03%. Suspension quantitative bactericidal test showed that the average killing logarithm (KL) value for both Staphylococcus aureus and Escherichia coli in 100 mg/L ClO2 solution for 2 min was over 5.00. in simulation field trial, the average descending KL value for Escherichia coli in the solution containing 100 mg/L ClO2 for 5 min was over 3.00. The mouse acute LD50 in the solution 5 times exceeded 5000 mg/kg. The disinfectant powder was not toxic and irritative to rabbit skin and had no mutagenic effect on mouse marrow polychromatic erythrocytes (PCE).</p><p><b>CONCLUSION</b>The stability and bactericidal efficacy of solid chlorine dioxide-based disinfectant powder in single-pack are good. The solution containing 100 mg/L ClO2 can kill vegetative forms of bacteria. The concentration of ClO2 on the disinfecting surface of objects is 100 mg/L. The disinfectant powder is not toxic and irritative.</p>

Sequencing and analysis of the complete genome of a rabies virus isolate from Sika deer / 病毒学报

One DRV strain was isolated from Sika Deer brain and sequenced. Nine overlapped gene fragments were amplified by RT-PCR through 3'-RACE and 5'-RACE method, and the complete DRV genome sequence was assembled. The length of the complete genome is 11863bp. The DRV genome organization was similar to other rabies viruses which were composed of five genes and the initiation sites and termination sites were highly conservative. There were mutated amino acids in important antigen sites of nucleoprotein and glycoprotein. The nucleotide and amino acid homologies of gene N, P, M, G, L in strains with completed genomie sequencing were compared. Compared with N gene sequence of other typical rabies viruses, a phylogenetic tree was established . These results indicated that DRV belonged to gene type 1. The highest homology compared with Chinese vaccine strain 3aG was 94%, and the lowest was 71% compared with WCBV. These findings provided theoretical reference for further research in rabies virus.

Metabonomic profile of urine from rats administrated with different treatment period of rifampin / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effect of rifampin (RFP) on the metabonomic profile of rat urine and its relationship with traditional toxicity evaluation of blood biochemical indicators and histopathology.</p><p><b>METHODS</b>Thirty-six male Wistar rats were randomly divided into control group, 50 mg/kg RFP group, and 100 mg/kg RFP group, with 12 rats in each group. Rats in each group were given intragastric infusion with a daily dose of 0, 50 mg/kg RFP, and 100 mg/kg RFP for 3, 7, and 14 days, respectively. Then 4 rats in each group were killed on the next day of administration to collect blood samples and liver sample for the determination of blood biochemical indicators and for the pathological analysis of the liver. The urine specimens over 24 hours of each rat were collected before and after each treatment until the rat was killed. 1H nuclear magnetic resonance (1H NMR) spectra of these urine specimens were acquired and subjected to data preprocess and principal component analyses (PCA).</p><p><b>RESULTS</b>The level of serum total bilirubin of the rat administrated with 100 mg/(kg x d) RFP for 7 days was significantly higher than that of control group (P < 0.05). Mild hepatotoxicity to the rat, treated with RFP of higher dosage (100 mg/kg) and longer duration (14 days), was revealed by the traditional histopathological method. The metabonomic spectra of rat urine in different groups differed from each other; a trajectory bias in determination of rat urine by 1H NMR occurred depending on the administration duration. As demonstrated by 1H NMR spectra of urine in rats treated with RFP, the concentration of urinary citrate and 2-oxoglutarate decreased, along with the remarkable increase of the concentrations of urinary taurine and glucose (compared with those of the control group).</p><p><b>CONCLUSIONS</b>Being consistent with the results of traditional toxicity evaluation measurements, metabonomic method is more sensitive. The 1H-NMR metabonomic profile of the rat urine is closely related with the duration of RFP. The hepatic toxicity induced by RFP is related to the reduction of energy metabolism in tricarboxylic acid cycle and the perturbation of glucose and lipid metabolism.</p>

Investigation on Levels of Polychlorinated Dibenzo-p-dioxins,Polychlorinated Dibenzo-p-furan and Polychlorinated Biphenyl in Milk in a City / 环境与健康杂志

Objective To know the levels of polychlorinated dibenzo-p-dioxins(PCDDs),polychlorinated dibenzo-p-furan (PCDFs)and polychlorinated biphenyl(PCBs)in milk and milk powder.Methods From Feb.2007 to Jun.2007,the milk and milk powder samples were collected and PCDDs,PCDFs and PCBs were extracted from the samples by Soxhlet extraction,cleaned up by FMS and quantified by HRGC-HRMS,using isotope dilution methodology.Results PCDDrFs and PCBs were detected in all samples.The mean levels of PCDD/Fs and dl-PCBs TEQ in the milk powder were 0.43 pg/g lipid(median:0.34 pg/g lipid),and in the packed milk were 3.83pg/g)lipid(median:2.04 pg/g lipid).The mean levels of PCDD/Fs and dl-PCBs TEQ in all samples were 2.13 pg/g lipid(median:0.815 pg/g lipid).The levels of PCDD/Fs and dioxin-like PCBs in the detected samples were far below the limitation of EU except of two milk samples,and the levels of PCDD/Fs and dioxin-like PCBs were higher in the packed milk than those in the milk powder.Conclusion Some of the milk and milk powder in the investigated city has been polluted by polychlorinated dibenzo-p-dioxins(PCDDs),polychlorinated dibenzo-p-furan(PCDFs)and polychlorinated biphenyl(PCBs).

Analysis on the status of Shigella spp antimicrobial resistance through data from the National Shigellosis Surveillance System in China, in 2005 / 中华流行病学杂志

<p><b>OBJECTIVE</b>The Ministry of Public Health released the National Surveillance project on Shigellosis in August, 2005. This study was to reveal the antimicrobial resistance status of Shigella isolates through the National Shigellosis Surveillance System in 2005 in China, so as to provide evidence for the development of surveillance, prevention and cure of Shigellosis.</p><p><b>METHODS</b>All the lab assistants received training from Chinese Center for Disease Control and Prevention. The project prescribed the uniform experimentation, quality control method, reagent, etc. Disc diffusion test(K-B) was carried out, following the CLSI methods. Data were analyzed by WHONET 5.4 software.</p><p><b>RESULTS</b>(1) 3 serotypes were identified and S. flexneri was common that accounted for 75.5% of all Shigella isolates followed by 24.4% of S. sonnei, but only 1 strain of S. dysenteriae was separated. (2) The resistant rates to tetracycline and ampicillin in Shigella spp were quite high, as over 90.0%. However, the resistant rate to Cefotaxime was the lowest, only 6.1%. The resistant rates were different between serotypes with the resistant rates of S. flexneri to ampicillin, ampicillin/clavulanate and ciprofloxacin were higher than those of S. sonnei (P < 0.001). (3) The multiple-antibiotic-resistance status in Shigella spp was quite serious and the resistant rate to five and more antimicrobials was 54.9%. The most common resistant patterns were seen on ampicillin, nalidixin, tetracycline and sulfamethoxazole. (4) There were some differences in subtypes and antimicrobial resistance among different provinces.</p><p><b>CONCLUSION</b>Cefotaxime seemed the best in curing Shigellosis at the clinic level. Programs regarding monitoring subtypes and antimicrobial resistance of Shigella should be in a continuous manner so as to understand the pathogens timely and to control the disease pertinently.</p>

Metabonomics profile of urine from rats administrated with different treatment period of isoniazid / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effect of different treatment period, of isoniazid (INH) on the metabonomic profile of rat urine and its relationship with traditional toxicity evaluation of blood biochemical indicators and histopathology and to explore the feasibility of metabonomics in the application of drug toxicity.</p><p><b>METHODS</b>Sixty male Wistar rats were orally administrated with 0, 50, 100, 200, and 400 mg x kg(-1) INH for 3, 7, and 14 days, respectively. Rat urine was then collected and its 1H nuclear magnetic resonance (NMR) spectra were acquired. All animals underwent traditional toxicity evaluation.</p><p><b>RESULTS</b>Hepatotoxicity was revealed by traditional toxicity evaluation in rats treated with higher dosage and longer treatment of INH. Time-response relationship existed during the treatment. Time-dependent metabonomics changes conformed with the results of traditional toxicity evaluation. The urine metabonomics showed a trajectory bias from those of the controls or pre-administration, and such bias exaggerated along with the prolongation of treatment, indicating a severer toxic injury. Along with the increase of the concentrations of urinary taurine and glucose and the decrease of the concentrations of urinary citrate and 2-oxoglutarate, the 1H NMR spectra of urine in rats treated with INH also changed.</p><p><b>CONCLUSIONS</b>The metabonomics technique can distinguish the onset and development of toxicity, which helps track and identify biomarkers. The hepatic toxicity induced by INH is related to the injury of mitochondrial function, reduction of energy metabolism in tricarboxylic acid cycle, and perturbations in the metabolism of glucose and lipid. The effect of INH on the rat urine metabonomic profile is related with INH toxicology. Therefore, metabonomics can be recognized as an ideal technique to explore and evaluate the drug toxicities.</p>

Effects of soy isoflavone on low-grade inflammation in obese rats / 中南大学学报(医学版)

OBJECTIVE@#To explore the effects of soy isoflavone (SIF) on low-grade inflammation in obese rats induced by high-fat diet, and to elucidate mechanisms of SIF in improving insulin sensitivity.@*METHODS@#Obese rats were randomly divided into 4 groups: One model control group and 3 SIF groups that were given water solutions with SIF at 0 mg/(kg x d), 50 mg/(kg x d), 150 mg/(kg x d), and 450 mg/(kg x d), respectively. After one month, fasting glucose, fasting insulin, interleukin-6, tumor necrosis factor-alpha, C-reactive protein, resistin, and adiponectin in serum were detected by enzymic method, radioimmunoassay, and enzyme linked immunosorbent assay, respectively.@*RESULTS@#In the 150 mg/(kg x d) group and 450 mg/(kg x d) group, fasting body-weights, viscera fatty deposition, and contents of insulin, interleukin-6, and tumor necrosis factor-alpha in serum were significantly lower; serum adiponectin levels were significantly higher; and serum resistin levels were significantly lower in the 450 mg/(kg d) group than those of the model control group. There was no difference in serum C-reactive protein levels among the 3 SIF groups.@*CONCLUSION@#Soy isoflavone may improve the insulin sensitivity by decreasing viscera fatty deposition and adjusting low-grade inflammatory molecules derived from white adipose tissues.

Effects of soy isoflavone on levels of low-grade inflammatory peptides in rats with insulin resistance / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effects of soy isoflavone (SIF) on low-grade inflammation in rats with high-fat diet-induced insulin resistance (IR) and explore the mechanisms of SIF in improving insulin sensitivity.</p><p><b>METHODS</b>The rats with high-fat diet-induced IR were randomly divided into one model control group and 3 SIF groups gavaged with SIF water solutions at the doses of 50, 150, and 450 mg/kg, respectively. One month after the treatment, fasting blood glucose (FBG), fasting insulin (FINS), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), resistin and adiponectin in the serum were detected by enzymatic method, radioimmunoassay, or enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>In the 150 and 450 mg/kg SIF groups, fasting body-weights, visceral adipose tissue deposition, FINS, resistin, TNF-alpha in serum, and IR index were lowered in comparison with the model control group, and in 450 mg/kg SIF group, serum IL-6 level was obviously lowered, and adiponectin increased. No differences were found in serum C-reactive protein levels between the 3 SIF groups.</p><p><b>CONCLUSION</b>Soy isoflavone may ameliorate insulin sensitivity by decreasing visceral adipose deposition and adjusting low-grade inflammatory molecules derived from white adipose tissue.</p>

Effects of zearalenone on proliferation and apoptosis in MCF-7 cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of zearalenone (ZEA) on proliferation and apoptosis in estrogen-dependent human breast cancer MCF-7 cells and the likely underlying molecular mechanisms.</p><p><b>METHODS</b>Cell viability was determined by MTT assay and cell cycle distribution by cytometry. Apoptosis was detected by Cell Death Detection ELISA and cytometry, respectively. The expressions of bax and bcl-2 were examined using multiple RT-PCR and Western-blot both at mRNA and protein level, respectively.</p><p><b>RESULTS</b>The current study confirmed the previous studies that ZEA could stimulate proliferation in MCF-7 cells with inducing a profound increase in S phase and a modest increase in G(2)/M phase that was accompanied by a decrease in G(0)/G(1) phase. ZEA could inhibit apoptosis in MCF-7 cells following estrogen ablation at a range of concentrations of 2 nmol/L -96 nmol/L. Western blot and RT-PCR analysis revealed that the anti-apoptotic bcl-2 was upregulated at both protein and mRNA level, together with the downregulation of pro-apoptotic bax.</p><p><b>CONCLUSION</b>ZEA should have possessed comparative estrogenic activity and could promote the progression of MCF-7 cells through the cell cycle by a decreasing in the G(0)/G(1) phase and by a significant increasing in S-phase. The pro-proliferative activity of ZEA was due to inhibition of apoptosis through regulation of bax/bcl-2 expression.</p>

Experimental studies on male reproductive toxicity of bisphenol A in vitro and vivo / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of Bisphenol A in adult rats and its possible mechanisms.</p><p><b>METHODS</b>BPA (in corn oil) was administered orally to 9-week-old male Sprague-Dawley rats for 14 days (0, 1 and 5 g/kg bw), and incubated primary Sertoli cells from pubertal SD rats with 0, 10(-7), 10(-6), 10(-5), 10(-4) mol/L BPA.</p><p><b>RESULTS</b>After oral administration, a significant decrease in right testis weight was observed in 5 g/kg dose group, but not in the 1 g/kg bw dose group. Germ cells were detached from basement membrane of seminiferous tubules and Sertoli cells in BPA-treated groups. Administration of BPA at 1 g/kg bw and 5 g/kg bw produced both nucleus pycnosis and vacuolized nucleus in germ cells and Sertoli cells. A marked loss in vimentin staining in Sertoli cells from testis of BPA-treated rats was detected. No change in levels of serum estradiol and testosterone was observed after two-week exposure to BPA. In Sertoli cell primary culture, BPA destroyed the cytoskeleton and cell-cell junctions, and elongated Sertoli cells.</p><p><b>CONCLUSION</b>These results suggest that BPA may injure reproductive function of male rats by destroying the cytoskeleton and changing the form of Sertoli cells.</p>