2012 Vol. 25, No. 5
2012, 25(5): 495-501. doi: 10.3967/0895-3988.2012.05.001
Objective To investigate the toxic effects of decabromodiphenyl ethane (DBDPE), used as an alternative to decabromodiphenyl ether in vitro.Methods HepG2 cells were cultured in the presence of DBDPE at various concentrations (3.125‐100.0mg/L) for 24, 48, and 72 h respectively and the toxic effect of DBDPE was studied.Results As evaluated by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide and lactate dehydrogenase assays and nuclear morphological changes, DBDPE inhibited HepG2 viability in a timeand dose‐dependent manner within a range of 12.5 mg/L to 100 mg/L and for 48 h and 72 h. Induction of apoptosis was detected at 12.5‐100 mg/L at 48 h and 72 h by propidium iodide staining, accompanied with overproduction of reactive oxygen species (ROS). Furthermore, N‐acetyl‐L‐cysteine, a widely used ROS scavenger, significantly reduced DBDPE‐induced ROS levels and increased HepG2 cells viability.Conclusion DBDPE has cytotoxic and anti‐proliferation effect and can induce apoptosis in which ROS plays an important role
Assessment of Iron Bioavailability in Ten Kinds of Chinese Wheat Flours Using an in vitro Digestion/Caco-2 cell Model
2012, 25(5): 502-508. doi: 10.3967/0895-3988.2012.05.002
Objective To compare iron bioavailability (Fe BV) from ten selected kinds of Chinese wheat flours in order to provide scientific basis for further human trials and enable plant breeding programs to screen biofortified wheat cultivars. Methods An in vitro digestion/Caco‐2 cell model was used to assess Fe BV of ten flour samples from six leading Chinese wheat cultivars and the stability of Fe BV in one cultivar was studied across three growing environments. Results Significant differences were observed in both Fe BV and Fe bioavailability per gram of food (Fe BVPG) among cultivars (P<0.01) grown at the same location with the same flour extraction rate. Zhongyou 9507 and Jingdong 8 had Fe BV 37%‐54% and Fe BVPG 103%‐154% higher than the reference control. In the Anyang environment, Zhongyou 9507 had a higher wheat flour‐Fe level and Fe BVPG. Differences in Fe BV were detected in cultivars with different flour extraction rates. Conclusion Zhongyou 9507 and Jingdong 8 were identified as the most promising cultivars for further evaluation of efficacy by using human subjects. The growing environments had no effect on Fe BV, but did have a significant effect on Fe BVPG. Fe bioavailabilities in low‐extraction (40%) flours were higher than those in high‐extraction (78%) flours.
Inactivated Sendai Virus Suppresses Murine Melanoma Growth by Inducing Host Immune Responses and Down-regulating β-catenin Expression
2012, 25(5): 509-516. doi: 10.3967/0895-3988.2012.05.003
Objective This paper aims to investigate the anti‐tumor mechanism of inactivated Sendai virus (Hemagglutinating virus of Japan envelope, HVJ‐E) for murine melanoma (B16F10). Methods The murine dendritic cells (DCs) were treated with HVJ‐E, and then the cytokines secreted from DCs and costimulation‐related molecules on DCs were measured. Meanwhile, the expression of β‐catenin in HVJ‐E treated murine melanoma cells was detected. In addition, HVJ‐E was intratumorally injected into the melanoma on C57BL/6 mice, and the immune cells, CTL response and tumor volume were analyzed.Results HVJ‐E injected into B16F10 melanoma obviously inhibited the growth of the tumor and prolonged the survival time of the tumor‐bearing mice. Profiles of cytokines secreted by dendritic cells (DCs) after HVJ‐E stimulation showed that the number of cytokines released was significantly higher than that elicited by PBS (P<0.05). The co‐stimulation‐related molecules on DCs were comparable to those stimulated by LPS. Immunohistochemical examinations demonstrated the repression of β‐catenin in B16F10 melanoma cells after HVJ‐E treatment. Meanwhile, real‐time reverse transcription PCR revealed that HVJ‐E induced a remarkable infiltration of CD11c positive cells, chemokine ligand 10 (CXCL10) molecules, interleukin‐2 (IL‐2) molecule, CD4+ and CD8+ T cells into HVJ‐E injected tumors. Furthermore, the mRNA expression level of β‐catenin in the HVJ‐E injected tumors was also down‐regulated. In addition, B16F10‐specific CTLs were induced significantly after HVJ‐E was injected into the tumor‐bearing mice. Conclusion This is the first report to show the effective inhibition of melanoma tumors by HVJ‐E alone and the mechanism through which it induces antitumor immune responses and regulates important signal pathways for melanoma invasion. Therefore, HVJ‐E shows its prospect as a novel therapeutic for melanoma therapy.
TNF-α and IL-1RA Polymorphisms and Silicosis Susceptibility in Chinese Workers Exposed to Silica Particles: A Case-Control Study
2012, 25(5): 517-525. doi: 10.3967/0895-3988.2012.05.004
Objective To assess the association of TNF‐α and IL‐1RA SNPs with the risk of silicosis in Chinese workers exposed to silica particles.Methods Case‐control study design was used to enroll 68 silicotic patients induced by silica particles and 68 healthy workers matched for length of silica particle exposure as controls. Both cases and controls were from the same company in southwest China, and each of them was requested to complete a questionnaire. Blood samples were drawn for genomic DNA extraction from each participant. The genotyping of TNF‐α (‐238 and ‐308) and IL‐1RA (+2018) was performed using polymerase chain reaction‐based restriction fragment length polymorphism (PCR‐RFLP) and SYBR green‐based quantitative polymerase chain reaction (qPCR), respectively. Unconditional logistic regression model was used to estimate odds ratios (Ors) and their 95% confidential intervals (CI) for SNPs. Results No significant differences were found between cases and controls in particles exposure length, body mass index (BMI), and status of smoking and alcohol consumption except for age (P=0.001) and blood type (P=0.042). The frequencies of TNF‐α (‐238) and IL‐1RA (+2018) genotypes in cases were significantly different from those in controls, (P=0.001 and P=0.002, respectively), while a borderline significant difference was found in the frequencies of TNF‐α (‐308) between cases and controls (P=0.063). The variants of three SNPs increased the risk of silicosis in the Chinese workers exposed to silica particles. The adjusted Ors of TNF‐α (‐308), TNF‐α (‐238) and IL‐1RA (+2018) were 2.8 (95% CI: 1.1‐7.5), 20.9 (95% CI: 1.8‐236.4) and 4.0 (95% CI: 1.6‐10.1), respectively. Conclusion It is suggested that cytokine polymorphisms of TNF‐α (‐238, ‐308) and IL‐1RA (+2018) are associated with the risk of silicosis in the Chinese workers exposed to silica particles. Further independent studies on the interaction between SNPs and exposure to silica particles with a larger sample size are therefore warranted.
The Relationship between Polymorphisms at 17 Gene Sites and Hypertension among the Aboriginal Tibetan People
2012, 25(5): 526-532. doi: 10.3967/0895-3988.2012.05.005
Objective The incidence of hypertension in Tibet ranks highest among all Chinese provinces. This may be due to genetic changes caused by Tibet's unique natural environment and agrarian lifestyle, prompting us to investigated the relationship between gene polymorphisms and hypertension. Methods Blood samples were collected from 229 hypertensive participants and 372 healthy (control) participants from five Tibetan counties. Seventeen single nucleotide polymorphisms were investigated for their connection to hypertension. Results The C allele at rs2070744 of the NOS3 gene was shown to be significantly associated with hypertension (P=0.0443; OR=1.636). Additionally, the T allele of rs4961 of the ADD gene was correlated with hypertension in women (P=0.03124; OR=1.584). Conclusion In this study we found that the NOS3 and ADD genes were related to a high incidence of hypertension among Tibetans. NOS3 gene plays a role in regulating vascular tone and blood vessel diameter, which may be altered by the low‐oxygen environment of Tibet. ADD is involved in water and salt metabolism, which is consistent with the high‐salt diet of Tibetans. The correlations elucidated by our study were different from those of other ethnic groups, indicating that these findings may be specific to the Tibetan people.
2012, 25(5): 533-541. doi: 10.3967/0895-3988.2012.05.006
Objective We identify ionizing radiation‐induced mitochondrial DNA (mtDNA) deletions in human lymphocytes and their distribution in normal populations. Methods Long‐range polymerase chain reactions (PCR) using two pairs of primers specific for the human mitochondrial genome were used to analyze the lymphoblastoid cell line following exposure to 10 Gy 60Co γ‐rays. Limited‐condition PCR, cloning and sequencing techniques were applied to verify the mtDNA deletions detected with long‐range PCR. Human peripheral blood samples were irradiated with 0, 2 and 6 Gy 60Co γ‐rays, and real‐time PCR analysis was performed to validate the mtDNA deletions. In order to know the distribution of mtDNA deletions in normal population, 222 healthy Chinese adults were also investigated. Results Two mtDNA deletions, a 7455‐bp deletion (nt475‐nt7929 in heavy strand) and a 9225‐bp deletion (nt7714 ‐nt369 in heavy strand), occurring between two 8‐bp direct repeats, were identified in lymphoblastoid cells using long‐range PCR, limited‐condition PCR and sequencing. These results were also observed for 60Co γ‐rays irradiated human peripheral blood cells. Conclusion Two novel mtDNA deletions, a 7455‐bp deletion and a 9225‐bp deletion, were induced by ionizing radiation. The rate of the mtDNA deletions within a normal population was related to the donors’ age, but was independent of gender.
Molecular Typing of Leptospira interrogans Strains Isolated from Rattus tanezumi in Guizhou Province, Southwest of China
2012, 25(5): 542-548. doi: 10.3967/0895-3988.2012.05.007
Objective To identify and type three leptospires isolated from Rattus tanezumi in Guizhou Province by using three molecular techniques (PFGE, MLVA, and MLST), reveal the molecular characteristic of causative agents of local leptospirosis and evaluate these three molecular methods based on their detection resolution and efficiency. Methods Three Leptospira strains were isolated from the kidney of Rattus tanezumi and cultured with EMJH medium. PFGE, MLVA, and MLST assays were applied to type the three strains isolated from Rattus tanezumi in Guizhou Province.Results PFGE, MLVA, and MLST typing showed that the three leptospiral isolates matched with leptospiral serogroup Icterohaemorrhagiae serovar Lai. The findings of the genotyping methods were consistent. MLVA and MLST defined genotypes, whereas PFGE allowed the recognition of additional subgroups within the genotypes, and the findings of molecular typing were also consistent with those of traditional techniques.Conclusion Three leptospiral isolates from Guizhou Province matched with leptospiral serogroup Icterohaemorrhagiae serovar Lai, and PFGE, MLVA, and MLST, as reliable molecular techniques for identifying and typing of Leptospira interrogans, would contribute to the active surveillance, outbreak investigation and source tracking for leptospirosis in Guizhou Province.
2012, 25(5): 549-556. doi: 10.3967/0895-3988.2012.05.008
Objective To evaluate the possible vascular effects of an environment carcinogen benzo(a)pyrene (BaP). Methods The cytotoxicit of BaP and rat liver S9 (0.25 mg/mL)‐activated BaP were examined by MTT assay. Thoracic aortic rings were dissected from Sprague‐Dawley rats. Contraction of aortic rings was induced by 60 mmol/L KCl or 10–6 mol/L phenylephrine (PE) in an ex‐vivo perfusion system after BaP (100 μmol/L) incubation for 6 h. [Ca2+]I was measured using Fluo‐4/AM. For in‐vivo treatment, rats were injected with BaP for 4 weeks (10 mg/kg, weekly, I.p.). Results BaP (1‐500 μm) did not significantly affect cell viability; S9‐activated BaP stimulated cell proliferation. BaP did not affect the contractile function of endothelium‐intact or ‐denuded aortic rings. BaP did not affect ATP‐induced ([Ca2+]I) increases in human umbilical vein endothelial cells. In BaP‐treated rats, heart rate and the number of circulating inflammatory cells were not affected. Body weight decreased while blood pressure increased significantly. The maximum aortic contractile responses to PE and KCl and the maximum aortic relaxation response to acetylcholine were significantly decreased by 25.0%, 34.2%, and 10.4%, respectively. Conclusion These results suggest, in accordance with its DNA‐damaging properties, that metabolic activation is a prerequisite for BaP‐induced cardiovascular toxicity.
2012, 25(5): 557-561. doi: 10.3967/0895-3988.2012.05.009
Objective To investigate the female sexual dysfunction (FSD) in type 2 diabetes patients, by comparing the sexual function between type 2 diabetic women and non‐diabetic women with Female Sexual Function Index (FSFI). Methods 115 type 2 diabetic women and 107 age‐matched non‐diabetes women were enrolled with similar backgrounds. Their sexual functions were evaluated with FSFI. Metabolic parameters such as body mass index, blood lipid profile, hemoglobin A1C, plasma glucose were also collected. Results Total score of FSFI of the type 2 diabetic women were significantly lower than that of the non‐diabetic controls (18.27±8.96 vs. 23.02±5.78, P=0.000). Scores of the FSFI domains (desire, arousal, lubrication, orgasm, satisfaction, pain) of the type 2 diabetic group were also lower than those of the control group. According to the FSD criterion (FSFI<25) available in China, the percentage of FSD in the type 2 diabetic group was significantly higher than that of the control group (79.2% vs. 55.0%, P<0.001). These trends seemed more prominent in pre‐menopause subgroups. The logistic regression analysis indicated that age and diabetes were independent risk factors of FSD. Body Mass Index (BMI) also had influence in the diabetes group.Conclusion Findings from this study showed that there are more FDS in Chinese type 2 diabetic women than in their non‐diabetic counterparts, especially in pre‐menopause participants.
2012, 25(5): 562-568. doi: 10.3967/0895-3988.2012.05.010
Objective There is little knowledge on whether there is clustering of inflammatory biomarkers, such as C‐reactive protein (CRP), soluble intracellular adhesion molecule1‐1 (sICAM‐1), and angiotensin II (Ang II), in individuals with hypertension in the Mongolian population. In the present study, we investigated this relationship in a Mongolian population in China. Methods A total of 2589 adult Mongolians, aged 20 years and older, were recruited as study participants. Data on demographics, lifestyle, family history of hypertension, blood pressure, and blood chemistry were collected, and inflammatory biomarkers were measured in all participants.Results The proportion of subjects with increased levels of two or three biomarkers was significantly higher in those with hypertension (21.0% and 6.0%, respectively) than in those with prehypertension (12.7% and 0.5%, respectively) or normotension (8.1% and 0.2%, respectively). The multivariate adjusted odds ratios (95% confidence interval) of hypertension associated with increased levels of one,two or three biomarkers were 0.94 (0.72‐1.22), 1.42 (0.93‐2.16), and 11.08 (1.45‐84.80), respectively, compared with subjects with no increase in any biomarker.Conclusion Hypertension was associated with a cluster of inflammatory biomarkers in the Mongolian population.
2012, 25(5): 569-576. doi: 10.3967/0895-3988.2012.05.011
Objective To develop a new technique for assessing the risk of birth defects, which are a major cause of infant mortality and disability in many parts of the world.Methods The region of interest in this study was Heshun County, the county in China with the highest rate of neural tube defects (NTDs). A hybrid particle swarm optimization/ant colony optimization (PSO/ACO) algorithm was used to quantify the probability of NTDs occurring at villages with no births.The hybrid PSO/ACO algorithm is a form of artificial intelligence adapted for hierarchical classification. It is a powerful technique for modeling complex problems involving impacts of causes.Results The algorithm was easy to apply, with the accuracy of the results being 69.5%±7.02% at the 95% confidence level.Conclusion The proposed method is simple to apply, has acceptable fault tolerance, and greatly enhances the accuracy of calculations.
Comparison of Concentrations of Lead and Cadmium in Various Parts of The Femur Head in Patients after Arthroplasty of The Hip Joint in Northwest Poland
2012, 25(5): 577-582. doi: 10.3967/0895-3988.2012.05.012
Objective To determine the concentrations of lead (Pb) and cadmium (Cd) in three kinds of materials (cartilage, cortical bone, and cancellous bone) of the femur head obtained from patients in the process of operation. Methods Concentrations of Pb and Cd were determined in selected parts of the femur head of 30 patients after total hip arthroplasty, using ICP‐AES (atomic absorption spectrophotometry). Results Pb contained the highest concentration in cortical bone, while Cd did so in cancellous bone. There were statistically significant differences in the concentrations of both elements between the cartilage and cortical bone, and also differences in the concentration of Pb between the cartilage and cancellous bone. There were no significant differences in the concentrations of Pb or Cd between cortical and cancellous bone.Conclusion Comparative studies on toxic metals should take into account both analogous bones and their fragments, as even if they come from the same kind of bones (e.g. femur head), clear differences exist in concentrations of heavy metals related to the sampling site and type of tissue (cartilage, cortical bone, and cancellous bone).
2012, 25(5): 583-589. doi: 10.3967/0895-3988.2012.05.013
Objective To examine UVB‐induced responses in normal human keratinocytes (HaCaT) and epidermoid carcinoma cells (A431) at the cellular and molecular level, and investigated the protective effect of salidroside.Methods Cells irradiated by UVB at various dosage and their viability was assessed by MTT assays, cell cycle was analysed by flow cytometry. The expression of NF‐κB, BCL‐2, and CDK6 after 50 J/m2 UVB irradiation were detected by RT‐PCR and western blotting.Results Our results confirmed greater tolerance of A341 cells to UVB‐induced damage such as cell viability and cell cycle arrest, which was accompanied by differential expression changes in NF‐κB,BCL‐2, and CDK6. UVB exposure resulted in HaCaT cells undergoing G1‐S phase arrest. When treated with salidroside, HaCaT survival was significantly enhanced following exposure to UVB, suggesting great therapeutic potential for this compound.Conclusion Taken together, our study suggests that A431 respond differently to UVB than normal HaCaT cells, and supports a role for NF‐κB, CDK6, and BCL‐2 in UVB‐induced cell G1‐S phase arrest.Furthermore, salidroside can effectively protect HaCaT from UVB irradiation.
Homology Modeling of Mosquitocidal Cry30Ca2 of Bacillus thuringiensis and Its Molecular Docking with N-acetylgalactosamine
2012, 25(5): 590-596. doi: 10.3967/0895-3988.2012.05.014
Objective To investigate the theoretical model of the three‐dimensional structure of mosquitocidal Cry30Ca2 and its molecular docking with N‐acetylgalactosamine.Methods The theoretical model of Cry30Ca2 was predicted by homology modeling on the structure of the Cry4Ba. Docking studies were performed to investigate the interaction of Cry30Ca2 with N‐acetylgalactosamine on the putative receptor.Results Cry30Ca2 toxin is a rather compact molecule composed of three distinct domains and has approximate overall dimensions of 95 by 75 by 60?. Domain ? Is a helix bundle, Domain II consists of three antiparallel β‐sheets, Domain III is composed of two β‐sheets that adopt a β‐sandwich fold. Residue 321Ile in loop1, residues 342Gln 343Thr and 345Gln in loop2, residue 393Tyr in loop3 of Cry30Ca2 are responsible for the interactions with GalNAc via 7 hydrogen bonds, 6 of them were related to the oxygen atoms of hydroxyls of the ligand, and one to the nitrogen of the ligand.Conclusion The 3D structure of Cry30Ca2 resembles the previously reported Cry toxin structures but shows still some distinctions. Several residues in the loops of the apex of domain II are responsible for the interactions with N‐acetylgalactosamine.
Association between Childhood Leukaemia and Exposure to Power-frequency Magnetic Fields in Middle Europe
2012, 25(5): 597-601. doi: 10.3967/0895-3988.2012.05.015
Objective Higher levels of exposure to extremely low‐frequency magnetic fields (ELF‐MF) are associated with a slightly increased risk of childhood leukaemia. Compared with more‐developed Western countries, higher exposure levels are evident in the Czech Republic, probably because of the different types of housing. In light of this, we aimed to examine the association between ELF‐MF exposure and childhood leukaemia in the Czech Republic.Methods We conducted a paired case‐control study. The cases (children with leukaemia) were agesex‐ and permanent residence‐matched to controls (children without leukaemia). Although this limited potential bias and confounding, it also limited our number of participants.Results The matched analyses included 79 case‐control pairs. No significant association between ELF‐MF exposure and childhood leukaemia was observed for exposures over 0.2 μT (odds ratio [OR]=0.93, confidence interval [CI]=0.45‐1.93), 0.3 μT (OR=0.77, CI=0.34‐1.75), or 0.4 μT (OR=0.9, CI=0.37‐2.22).Conclusion Despite higher levels of exposure in Middle and Eastern Europe, no indication of an association between ELF‐MF exposure and childhood leukaemia was determined. This in contrast to the findings of previous studies conducted in different countries.
2012, 25(5): 602-605. doi: 10.3967/0895-3988.2012.05.016
The number of human rabies cases acquired from dog bites constitutes a high proportion of the total rabies cases in China, although the number of human rabies cases has gradually decreased in recent years. The pivotal role of dogs in the spread of rabies indicates that controlling and preventing canine rabies could be a key step in eradicating human rabies in China. The primary aims of this review are to discuss the properties and pathogenesis of the rabies virus, the clinical signs and diagnosis of canine rabies, threshold host density and vaccination of dogs, and the prevention and control of canine rabies in China.