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Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops
ISLAM Ejaz ul, YANG Xiao-e, HE Zhen-li, MAHMOOD Qaisar
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 1-13.
https://doi.org/10.1631/jzus.2007.B0001
Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity.
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Biodegradability of leachates from Chinese and German municipal solid waste
SELIC E., WANG Chi, BOES N., HERBELL J.D.
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 14-19.
https://doi.org/10.1631/jzus.2007.B0014
The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.
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Effect of calcium and light on the germination of Urochondra setulosa under different salts
SHAIKH Faiza, GUL Bilquees, LI Wei-qiang, LIU Xiao-jing, KHAN M. Ajmal
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 20-26.
https://doi.org/10.1631/jzus.2007.B0020
Urochondra setulosa (Trin.) C.E. Hubbard is a coastal halophytic grass thriving on the coastal dunes along the Pakistani seashore. This grass could be useful in coastal sand dune stabilization using seawater irrigation. The purpose of this investigation was to test the hypothesis that Ca2+ (0.0, 2.5, 5.0, 10.0 and 50.0 mmol/L) alleviates the adverse effects of KCl, MgSO4, NaCl and Na2SO4 at 0, 200, 400, 600, 800 and 1000 mmol/L on the germination of Urochondra setulosa. Seed germination was inhibited with increase in salt concentration with few seeds germinated at and above 400 mmol/L concentration. No seed germinated in any of the KCl treatments. Inclusion of CaCl2 substantially alleviated the inhibitory effects of all salts. Germination was higher under photoperiod in comparison to those seeds germinated under complete darkness. Among the CaCl2 concentrations used, 10 mmol/L was most effective in alleviating salinity effects and allowing few seeds to germinate at 1000 mmol/L KCl, MgSO4, NaCl and Na2SO4 solution.
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Optimization of fermentation conditions for P450 BM-3 monooxygenase production by hybrid design methodology
LU Yan, MEI Le-he
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 27-32.
https://doi.org/10.1631/jzus.2007.B0027
Factorial design and response surface techniques were used to design and optimize increasing P450 BM-3 expression in E. coli. Operational conditions for maximum production were determined with twelve parameters under consideration: the concentration of FeCl3, induction at OD578 (optical density measured at 578 nm), induction time and inoculum concentration. Initially, Plackett-Burman (PB) design was used to evaluate the process variables relevant in relation to P450 BM-3 production. Four statistically significant parameters for response were selected and utilized in order to optimize the process. With the 416C model of hybrid design, response surfaces were generated, and P450 BM-3 production was improved to 57.90×10−3 U/ml by the best combinations of the physicochemical parameters at optimum levels of 0.12 mg/L FeCl3, inoculum concentration of 2.10%, induction at OD578 equal to 1.07, and with 6.05 h of induction.
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Oogenesis in summer females of the rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), in southern Zhejiang, China
SHI Sheng-wei, JIANG Ming-xing, SHANG Han-wu, LV Hui-ping, CHENG Jia-an
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 33-38.
https://doi.org/10.1631/jzus.2007.B0033
The rice water weevil, Lissorhoptrus oryzophilus Kuschel, has two generations in southern Zhejiang, China. To determine oogenesis in first-generation females (summer females) and its relations to temperature, females were collected from a rice field in early and mid-July and reared on young rice plants at 28, 31 and 34 °C in the laboratory. Percentage of females having oocytes, number of oocytes of different stages (stage-I, from early previtellogenesis to middle vitellogenesis; stage-II, late vitellogenesis; and mature-oocyte stage), and length of ovarioles were determined every 10 d of feeding. At each temperature, oogenesis took place in over 40% of females after 20~40 d of feeding, but only 0.0~3.3 stage-I, 0.0~0.8 stage-II and 0.0~1.1 mature oocytes were observed at each observation date. Temperature had significant effect on number of stage-I oocytes but not on number of stage-II and mature oocytes in early July females; temperature had no significant effect on number of oocytes of either stage in mid-July females. Conclusively, in southern Zhejiang, summer L. oryzophilus females have great potential to become reproductive on rice, but their oogenesis activity is very low, with the overall procedures little affected by temperature.
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FoxO4 is the main forkhead transcriptional factor localized in the gastrointestinal tracts of pigs
ZHOU Zhen-qi, WANG Tian, PAN Ling-mei, HUANG Rui-hua, SHI Fang-xiong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 39-44.
https://doi.org/10.1631/jzus.2007.B0039
Forkhead box (Fox) proteins play critical roles in the regulation of differentiation, proliferation, immunity and aging of cells. Most studies on Fox proteins are limited to cultured cells and rodent. The aim of the current study is to detect by immunohistrochemistry whether FoxO1, FoxO3a and FoxO4 proteins are localized in the stomach and intestine of the pig. The results showed that FoxO4 exists in the mucosa in all parts of the stomach and intestine; FoxO3a exists mainly in the lamina propria and muscularis of some parts. However, FoxO1 is not detectable in all parts of the stomach and intestine. Collectively, the results of the present study indicate that there exists a distinct expression pattern of Fox proteins, and that FoxO4 is a primary forkhead transcriptional factor localized in the gastrointestinal tracts of the pig.
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Comparison of the performance of chiral stationary phase for separation of fluoxetine enantiomers
ZHOU Jie, YANG Yi-wen, WEI Feng, WU Ping-dong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 56-59.
https://doi.org/10.1631/jzus.2007.B0056
Separation of fluoxetine enantiomers on five chiral stationary phases (chiralcel OD-H, chiralcel OJ-H, chiralpak AD-H, cyclobond І 2000 DM and kromasil CHI-TBB) was investigated. The optimal mobile phase compositions of fluoxetine separation on each column were hexane/isopropanol/diethyl amine (98/2/0.2, v/v/v), hexane/isopropanol/diethyl amine (99/1/0.1, v/v/v), hexane/isopropanol/diethyl amine (98/2/0.2, v/v/v), methanol/0.2% triethylamine acetic acid (TEAA) (25/75, v/v; pH 3.8) and hexane/isopropanol/diethyl amine (98/2/0.2, v/v/v), respectively. Experimental results demonstrated that baseline separation (RS>1.5) of fluoxetine enantiomers was obtained on chiralcel OD-H, chiralpak AD-H, and cyclobond І 2000 DM while the best separation was obtained on the last one. The eluate orders of fluoxetine enantiomers on the columns were determined. The first eluate by chiralcel OJ-H and kromasil CHI-TBB is the S-enantiomer, while by chiralpak AD-H and cyclobond I 2000 DM is the R-enantiomer.
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Acute lung injury/acute respiratory distress syndrome (ALI/ARDS): the mechanism, present strategies and future perspectives of therapies
LUH Shi-ping, CHIANG Chi-huei
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 60-69.
https://doi.org/10.1631/jzus.2007.B0060
Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), which manifests as non-cardiogenic pulmonary edema, respiratory distress and hypoxemia, could be resulted from various processes that directly or indirectly injure the lung. Extensive investigations in experimental models and humans with ALI/ARDS have revealed many molecular mechanisms that offer therapeutic opportunities for cell or gene therapy. Herein the present strategies and future perspectives of the treatment for ALI/ARDS, include the ventilatory, pharmacological, as well as cell therapies.
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Hypertonic saline resuscitation maintains a more balanced profile of T-lymphocyte subpopulations in a rat model of hemorrhagic shock
LU Yuan-qiang, CAI Xiu-jun, GU Lin-hui, MU Han-zhou, HUANG Wei-dong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(1): 70-75.
https://doi.org/10.1631/jzus.2007.B0070
Objective: To investigate the potential and early effect of hypertonic saline resuscitation on T-lymphocyte subpopulations in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 18 Sprague-Dawley (SD) rats. The rats were randomly divided into Sham group, HTS group (hypertonic saline resuscitation group) and NS group (normal saline resuscitation group). Each group contained 6 rats. The CD4+ and CD8+ subpopulations of T-lymphocytes in peripheral blood were detected respectively before shock and after resuscitation by double antibody labelling and flow cytometry. Results: In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the CD4+ lymphocytes of peripheral blood in HTS and NS groups markedly increased. Small volume resuscitation with HTS also induced peripheral CD8+ lymphocytes to a certain extent, whereas NS resuscitation showed no effect in this respect. Consequently, compared with Sham and HTS groups, CD4+/CD8+ ratio of peripheral blood in NS group was obviously increased, and showed statistically differences. Conclusion: In this model of rat with severe hemorrhagic shock, small volume resuscitation with HTS is more effective than NS in reducing immunologic disorders and promoting a more balanced profile of T-lymphocyte subpopulations regulating network.
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11 articles
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