山东省某轻稀土矿区粮食中稀土元素含量与健康风险

目的了解山东某轻稀土矿区与非矿区粮食中稀土元素含量及其健康风险。方法于2014年7—10月,采集调查区域内村民自己种植的粮食(小麦、玉米和大豆)样品339份,采用电感藕合等离子体质谱仪(ICP-MS)测定15种稀土元素的含量。结果矿区粮食中总稀土元素含量为9.85~4 268.39μg/kg,中位数为82.47μg/kg;非矿区粮食中总稀土元素含量为1.55~2 662.31μg/kg,中位数为54.75μg/kg。矿区和非矿区粮食中稀土元素含量差异无统计学意义(P0.05)。矿区和非矿区均为小麦稀土元素含量最高(128.79μg/kg和85.14μg/kg),玉米最低(44.89μg/kg和37.95μg/kg)。粮食中稀土元素以富集轻稀土元素为特征。通过粮食摄入的稀土元素远小于健康指导值。结论矿区和非矿区粮食中稀土元素含量无差异,以轻稀土元素为主,通过小麦、玉米、大豆摄入的稀土元素不会危害人体健康。     

13C呼气法研究膳食纤维对健康受试者碳水化合物代谢的影响

目的 观察复合膳食纤维对摄入玉米淀粉试餐后的健康受试者碳水化合物代谢的影响.方法 将12例健康志愿者采用随机表随机分为2组,每组6人.采用随机、开放、双周期、交叉设计.第一周期,一组接受无纤维玉米淀粉试餐,另一组接受高纤维玉米淀粉试餐(含膳食纤维16 g).采集受试者空腹及摄入试餐后0.5、1.0、1.5、2.0、2.5、3.0、3.5、4.0、5.0、6.0、7.0、8.0 h的呼气样本,进行"CO2的测定.受试者完成第1周期试验后,中间经过1周的洗脱期,两组受试者交叉,重复上述试验.结果 受试者摄人不同试餐后,无纤维膳食组第0.5、1.5、2.0、2.5、3.0和4.0小时13CO2高于本底的δ值变化分别为0.79、2.03、2.57、2.86、3.02和3.18,高纤维膳食组分别为0.16、1.33、1.77、2.10、2.34和2.42,无纤维膳食组高于高纤维膳食组,P值分别为0.014、0.014、0.011、0.018、0.036和0.020;无纤维膳食组13CO2高于本底的δ值变化峰值为3.18,高纤维膳食组为2.56,两组比较差异无统计学意义(P>0.05);无纤维膳食组达峰时间为4.0 h,高纤维膳食组为3.5 h,高纤维膳食组有明显延迟(P=0.032).无纤维膳食组0.5～6.0 h内各点的13CO2的累积回收率分别为0.41、1.46、3.15、5.50、8.28、11.30、14.42、17.62、23.65和28.78,高纤维膳食组分别为0.09、0.55、1.61、3.22、5.23、7.53、10.09、12.68、17,60和22.27,两组差异具有统计学意义,P值分别为:0.014、0.018、0.018、0.014、0.013、0.014、0.018、0.020、0.025和0.044.6.0 h以后13CO2的累积回收率两组比较差异无统计学意义(P>0.05).结论 本试验所用复合膳食纤维可以使6.0 h以内碳水化合物的氧化率降低,但对碳水化合物的总氧化率无影响.     

Subchronic feeding study of DAS-59122-7 maize grain in Sprague-Dawley rats.

59122 is a transgenic maize line containing event DAS-59122-7 that expresses the corn rootworm (CRW) specific pesticidal Cry34Ab1 and Cry35Ab1 proteins from Bacillus thuringiensis (Bt) Berliner strain PS149B1 and the phosphinothricin-N-acetyltransferase (PAT) protein from Streptomyces viridochromogenes for tolerance to the herbicidal ingredient glufosinate-ammonium. For the current study, 59122 maize grain, non-transgenic near-isogenic maize grain (091), and a commercially available non-transgenic reference maize grain (33R77) were grown under conditions simulating commercial farming practices. Adult Sprague-Dawley rats (12/sex/group) were fed diets formulated with 35% maize grain from either 59122, 091, or 33R77, or one of two separate lots of commercially available rodent chow prepared with commercially available corn (35%) in accordance with the standards of Purina Mills Labdiet 5002 for approximately 90 days. All diets possessed similar nutritional and contaminant profiles. The transgenic proteins were detected only in diets prepared with 59122 maize grain and were stable over the course of the study. Compared to control groups, no adverse diet-related differences were observed in rats fed diets formulated with 59122 maize grain with respect to body weight/gain, food consumption/efficiency, clinical signs of toxicity, mortality, ophthalmology, neurobehavioral (FOB and motor activity) assessments, clinical pathology (hematology, clinical chemistry, coagulation, and urinalysis), and pathology (organ weights and gross and microscopic pathology). Results from this study indicate that 59122 maize grain is nutritionally equivalent to and as safe as conventional maize grain.     

Subchronic feeding study with genetically modified stacked trait lepidopteran and coleopteran resistant (DAS-Ø15Ø7-1xDAS-59122-7) maize grain in Sprague-Dawley rats

DAS-Ø15Ø7-1xDAS-59122-7 (1507 × 59122) is a genetically modified (GM) maize hybrid that was produced by crossing of two GM maize inbreds; DAS-Ø15Ø7-1 and DAS-59122-7. This hybrid cross expresses four transgenic proteins: Cry1F and PAT (from DAS-Ø15Ø7-1) and Cry34Ab1/Cry35Ab1 and PAT (from DAS-59122-7) that confer resistance to lepidopteran and coleopteran pests and tolerance to the herbicidal active ingredient glufosinate-ammonium. The current subchronic feeding study was conducted in Sprague-Dawley rats to evaluate the potential health effects of long-term consumption of a rodent diet containing 1507 × 59122 maize grain compared with a diet containing maize grain from its near-isogenic control (091). Diets formulated with three unrelated non-GM commercial hybrids (3573, 35P12, 36G12) were also included for within study reference data. All diets contained 34% (w/wt) maize grain and were prepared according to the specifications of PMI^® Nutrition International, LLC Certified Rodent LabDiet^® 5002 (PMI^® 5002). Diets were fed ad libitum to rats for at least 92 days. OECD 408 response variables from rats fed the 1507 × 59122 diet were compared with those from rats fed the 091 control diet. No toxicologically significant differences were observed in nutritional performance variables, clinical and neurobehavioral signs, ophthalmology, clinical pathology (hematology, clinical chemistry, coagulation, and urinalysis), organ weights, and gross and microscopic pathology between rats in the 091 and 1507 × 59122 treatment groups. The results from this study demonstrate that 1507 × 59122 maize grain is as safe and nutritious as non-GM maize grain and support the concept that crossing of two safe GM maize events results in production of a safe stacked GM event.     

克山病区与非病区主粮中氨基酸含量对比分析

本文通过对克山病区及非病区主粮小麦、玉米中氨基酸的对比分析,探讨氨基酸含量与克山病的发病关系。从所测的17种氨基酸结果表明:小麦及玉米中的氨基酸含量,病区均低于非病区;小麦中以蛋氨酸含量最低、半胱氨酸次之,玉米中以半胱氨酸含量最低,蛋氨酸次之,这说明进入生物体内含硒氨基酸(蛋氨酸、半胱氨酸)是缺乏的。还证实粮中氨基酸含量多寡受产地生态环境的影响。病区人体从食物链中摄取需要的氨基酸及其营养物含量不足与克山病的发病有密切关系。     

Plasma lipid effects of corn oil and extra-virgin olive oil in hypercholesterolaemic subjects: a randomised, controlled trial

The aim of our study was to directly compare the metabolic effect of monounsaturated fatty acid rich oils and polyunsaturated fatty acid rich oils on the plasma lipid pattern of moderately hypercholesterolaemic subjects under controlled isocaloric condition. After a 30-day run-in diet, 44 healthy Caucasian subjects with moderate hypercholesterolaemia were randomly assigned to one of four different isocaloric diets, differing only regarding the oil used (corn oil, corn oil supplemented with vitamin E, extra-virgin olive oil or different self-selected oils), for 45 days. At the end of the study, when compared to the baseline value, low-density lipoprotein (LDL)-cholesterolaemia was significantly lower only in patients taking corn oil (−13.9%; 95%CI −5.9 to −20.1; p = 0.02) or corn oil with added vitamin E (−19.1%; 95%CI −6.9 to −24.1; p = 0.03). Differences in plasma high-density lipoprotein (HDL)-cholesterol and triglyceride levels from baseline levels and between the four diets did not reach statistical significance.     

Optimization of microwave-assisted extraction procedure for zinc and copper determination in food samples by Box-Behnken design

This article describes the application of response surface methodology (RSM) to the development of a procedure for zinc and copper determination by flame atomic absorption spectrometry (FAAS) in food samples after extraction by a microwave system. A Box-Behnken matrix was used to find optimal conditions for the procedure through a response surface study. Three variables “irradiation power; time; and temperature” were regarded as factors in the optimization study. The working conditions were established as a compromise between optimum values found for each analyte taking into consideration the robustness of the procedure. These values were 97 °C, 90 W and 9.0 min, for temperature, irradiation power and time, respectively. The accuracy of the optimized procedure was evaluated by the analysis of certified reference materials. The method was applied to the determination of copper and zinc in wheat flour and corn flour samples.     

Effective removal of pharmaceutical contaminants ibuprofen and sulfamethoxazole from water by Corn starch nanoparticles: An ecotoxicological assessment

Pharmaceutical pollutants, a vital type of emerging contaminants, have attracted researchers to study their removal from water. In this research, Corn starch nanoparticles (CSNP) have been synthesized and characterized using various analytical techniques. The synthesized CSNP was used for the biosorption of two pharmaceutical drugs, ibuprofen (IBU) and sulfamethoxazole (SUL). The influence of various experimental conditions was optimized through batch study with the removal efficiency of 86.33 % (IBU) and 85.80 % (SUL) at pH 2 and 3, initial concentration of 10 mg/L, 0.01 g of CSNP dosage. The biosorption of IBU follows Temkin, and SUL follows Langmuir isotherm models. The toxicological assessment was performed using the seeds of Vigna mungo (VM) and Vigna radiata (VR) and zebrafish to evaluate the toxic effects of pollutants on these organisms. The LC₅₀ of IBU and SUL on zebrafish before the biosorption process was 209.50 mg/L and 338.84 mg/L. After biosorption, the LC₅₀ values increase to 1435.82 mg/L for IBU and 1317.04 mg/L for SUL. Thus, CSNP is an efficient biosorbent for removing the pharmaceutical pollutants to protect ecological systems.     

Isolated Plantar Vein Thrombosis Resembling a Corn with a Bruise

Plantar vein thrombosis, rarely-reported disease, is usually accompanied by pain and tenderness in the plantar region and should be differentiated from other dermatological conditions causing plantar pain, such as hemorrhagic corn/callus, plantar epidermal cyst, verruca, or plantar fibromatosis. A 52-year-old man presented with a violaceous tender subcutaneous nodule overlying a hyperkeratotic plaque on his sole. Initially, he thought it was a corn and applied keratolytic agents, which failed to work. Sonography revealed a well-demarcated mass with increased peripheral vascularity. His pain was relieved after a complete wide excision, which confirmed the mass to be plantar vein thrombosis after histopathological examination.