Tracing Pb Pollution Penetration in Temperate Podzols

We combine high‐resolution soil sampling with lead (Pb) analyses (concentrations and stable isotopes) in two temperate podzols, together with previous data obtained with selective Al and Fe dissolution techniques. We aim to assess how atmospheric Pb is incorporated into the soils during pedogenesis. Partial least squares modelling for Pb concentrations shows that the podzolization process has the largest effect on Pb concentration (80·3% of the variance). The proportion of inorganic secondary compounds, the input of fresh organic matter from the soil surface and the relative abundance of Fe versus Al are responsible for a small part of the Pb concentration variance. Lead isotopic composition (²⁰⁶Pb/²⁰⁷Pb ratios) depends on soil organic matter content either fresh/poorly humified (57·3% of the variance) or humified (24·7% of the variance). The Pb linked to inorganic compounds and the overall podzolization process play a minor role in isotopic signature (5·3 and 3·7% of the variance respectively). Soil pH appears to be the controlling variable of the different transport and retention mechanisms. The relatively low isotopic ratios observed in spodic horizons result from geogenic Pb released through the preferential dissolution of the isotopically distinct most weatherable minerals of the parent material in the eluvial horizons, which undergoes downward mobilization. An accurate knowledge of soil reactive components and formation mechanisms is essential to a correct diagnose of the scope of Pb pollution and a more effective design of remediation strategies. Copyright © 2017 John Wiley & Sons, Ltd.     

近40 a黄河乌兰布和沙漠段河道演变特征

基于Landsat系列卫星遥感数据,利用目视解译法提取黄河乌兰布和沙漠段近40 a夏季河道演变特征值,对比分析两岸河道演变特征并分析其变化原因.结果表明:①以乌海水利枢纽为起点,1973-2015年黄河乌兰布和沙漠段左岸堆积面积最大的河段分布在11.5 ～36.7 km处,右岸堆积面积最大的河段分布在61.5～73.1 km处;②1973-2015年黄河乌兰布和沙漠段堆积与侵蚀总面积分别为82.73 km2和5.28 km2,其中1973-1989、1989-2000、2000-2005、2005-2008、2008-2010年和2010-2015年各时期的堆积速率分别为1.52 km2·a-1、2.36kim2·a-1、3.70km2 ·a-1、2.45 km2 ·a-1、1.22 km2·a-1和0.84 km2·a-1.黄河乌兰布和沙漠段整体呈现淤积状态,河道萎缩并向右迁移;③随着石嘴山水文站年均径流量的增大,河岸堆积速率呈逐渐降低趋势,而侵蚀速率变化趋势则正好相反.该研究有利于了解黄河上游沙漠宽谷河段的河道演变特征,为沙漠地区植被恢复及当地环境的治理提供理论依据.     

石墨炉原子吸收光谱法测定新资源食品中的硒含量

建立一种简便、快速、准确的食品中硒的测定方法;检测新资源食品芝麻叶、野生四叶参、野生菜葛根、野生葛花及桑蚕蛹中的硒含量。用1mg·mL-1硝酸镍为基体改进剂,加入体积分数为0.1%TritonX-100和0.5%硝酸(1∶1),以改善样液的表面张力。用HITACHIZ-5000型石墨炉原子吸收光谱仪及全自动进样方法进行硒含量测定。石墨炉采用光控升温方式,硒的灰化温度按程序升温方式进行,程序升温分为干燥、灰化、原子化和净化。该方法的测定限为18.6μg/L,精密度为3.26%￣9.29%(RSD),加标回收率为92.1%￣108.8%。该方法具有测定简便、快速和准确等特点,可作为食品中硒含量测定的良好方法。     

Effects of Selenium Yeast on Growth Performance and Some Blood Biochemical Indexes in Laying Ducks of Rearing Period in Cages under High Ambient Temperature

The study was conducted to determine the effects of different levels of selenium yeast(SeY, added as selenium content) on growth performance and some biochemical indexes in Jinding laying ducks under high temperature (29-35℃). 144 Jinding laying ducks of rearing period (10-16 weeks old) were divided into 4 groups, control group, experimental groups Ⅰ,Ⅱ and Ⅲ, supplemented with 0, 0.15, 0.45 and 0.75 mg/kg Se, respectively. The results showed that compared with the control group, the addition of SeY to the diets could significantly increase the average daily feed intakes (ADFI) of ducks at 14-16 weeks old (P<0.05); The body weights of ducks in group Ⅰ at 13-15 weeks old were significant higher than that in the control group (P<0.05),and the body weight at 16 weeks old was higher than the other three groups significantly (P<0.05),there was no significant difference between the body weight and standard body weight at 16 weeks old in group Ⅰ(P>0.05), but the body weights of other three groups were extremely significantly lower than the standard weight (P<0.01); There was no significant difference among the four groups for feed to gain ratios (F/G), while the group Ⅰ was the lowest; AST activities of group Ⅰ were significantly lower than group Ⅱ(P<0.05), LDH activities of groups Ⅰ,Ⅱ and Ⅲ were lower than the control group significantly (P<0.05), and LDH activities of groupⅠ were lower than groups Ⅱ and Ⅲ significantly (P<0.05). TCH concentrations of groups Ⅰ and Ⅱ were higher than group Ⅲ significantly (P<0.05). It is concluded that the addition of 0.15 mg/kg of Se (added as SeY) could obviously improve the growth performance of the laying ducks in reared cages, protect the function of liver, promote the TCH concentrations of duck serum.     

Therapeutic Plasma Exchange for Venom-Induced Thrombotic Microangiopathy Following Hump-Nosed Pit Viper (Genus: Hypnale) Bites: A Prospective Observational Study

Introduction—Thrombotic microangiopathy (TMA), which is the triad of acute kidney injury (AKI), microangiopathic hemolytic anemia (MAHA), and thrombocytopenia, is a rare complication of snakebites, and in Sri Lanka, it is commonly seen with hump-nosed pit viper (HNPV) bites.Methods—We conducted a prospective observational study of patients with AKI caused by HNPV bites in Teaching Hospital, Ratnapura, Sri Lanka for 6 y, commencing in June 2015. Some patients with TMA underwent therapeutic plasma exchange (TPE) and some did not. These 2 groups were compared. Statistical analysis was carried out using Minitab 18.1. Data were presented as median (IQR).Results—There were 52 (8%) patients with TMA, of whom 21 (45%) were in the TPE group and 26 (55%) were in the non-TPE group. TPE improved time to platelet correction (4 d [IQR, 4–5 d] vs 7 d [IQR, 5–9 d]; P=0.009), time to MAHA correction (5 d [IQR, 3–4 d] vs 7 d [IQR, 6–9 d]; P=0.004), time to prothrombin time (PT)/international normalized ratio (INR) correction (1 d [IQR, 1–2 d] vs 3 d [IQR, 3–4 d]; P=0.003), and time to 20 min whole blood clotting test (WBCT20) correction (2 d [IQR, 1–2 d] vs 3 d [1QR 2–3 d]; P=0.020). Renal recovery was predicted by TPE (P=0.048) and highest creatinine level (P=0.001). There was no association between TPE and dialysis dependency at discharge (P=0.597), length of hospital stay (P=0.220), and the number of dialysis cycles prior to discharge (P=0.540). TPE did not improve the number of blood transfusions (5 packs [IQR, 3–8.5 packs] vs 4 packs [IQR, 0–9 packs]; P=0.290).Conclusions—TPE is effective for TMA in the early correction of platelet counts, MAHA, PT/INR, and WBCT20 in HNPV bites.     

Effect of Luteolin on Blood Indexes,Liver and Kidney in Mice with Acute Mercury Poisoning

To study the effect of luteolin on blood indexes,liver and kidney in mice with acute mercury poisoning,28 mice were randomly divided into four groups:Control group (intraperitoneal injection 0.9% saline),luteolin group (lavage 100 mg/kg luteolin),mercuric chloride group (intraperitoneal injection 4 mg/kg mercury chloride) and mercury chloride+luteolin group (intraperitoneal injection 4 mg/kg mercuric chloride,lavage 100 mg/kg luteolin).The activities of ALT in serum,AST,CREA and BUN contents,blood WBC,RBC,HGB content and GSH and MDA contents of liver tissue were detected.Morphological changes of liver and kidney tissues were observed.The results showed that compared with the control group,the activities of ALT and AST of mercuric chloride group were extremely significantly increased (P < 0.01),serum CREA,BUN,blood WBC and liver tissue MDA contents were significantly increased (P < 0.05) while blood RBC,HGB and liver tissue GSH contents were significantly decreased (P < 0.05).Liver,kidney pathological changes were obviously.Compared with mercuric chloride group,the activities of ALT,AST in serum,CREA,BUN,blood WBC and liver tissue MDA contents of mercuric chloride+luteolin group were significantly decreased (P < 0.05),while blood RBC,HGB and liver tissue GSH contents were significantly elevated (P < 0.05).Liver,kidney pathological changes were attenuated obviously.The poisoning were characterized by inflammation and the occurrence of anemia when acute mercury poisoning occurred,liver and kidney showed different degrees of injury in mice.Luteolin could reduce the toxic effects of acute mercury poisoning on blood,liver and kidney.     

Kruppel样因子15对脂肪沉积和肌纤维类型的影响及其可能机制

Kruppel样因子15(KLF15)是一种新发现的Kruppel样因子家族(KLFs)成员,为一种真核锌指蛋白转录因子。KLF15在动物体内呈现多组织表达特性,该基因过表达能促进动物脂肪沉积,且能影响肉质性状候选基因和Ⅰ型肌纤维基因的表达。因此,深入研究KLF15对脂肪沉积和肌纤维类型的影响及其可能机制,将为改善动物肉品质提供新的思路。本文综述了KLF15的发现、结构特征、表达规律及其与脂肪沉积和Ⅰ型肌纤维之间的关系。     

Protective effects of selenium and vitamin E on rats consuming maize naturally contaminated with mycotoxins

Protective effects of antioxidant additives of selenium and vitamin E on rats that consumed maize naturally contaminated with mycotoxins were explored in this paper. Thirty-two Wistar female rats were randomly divided into four groups. The control group was given the basic diet with normal maize. The contaminated maize group was given the diet in which normal maize was replaced by mycotoxin-contaminated maize. The selenium group and vitamin E group were respectively fed mycotoxincontaminated diet supplemented with 0.4mg · kg⁻¹ selenium from yeast or 100 mg · kg⁻¹ vitamin E. The trial lasted for 4 weeks. Compared with the control group, antioxidative status was decreased significantly in the contaminated maize group. However, the status in the selenium group and vitamin E group was increased significantly compared with the contaminated maize group. The activities of enzymes related to liver function were significantly higher in the contaminated maize group than those in the control group, whereas they were significantly lower in the selenium group and/or the vitamin E group compared to the contaminated maize group. It is concluded that selenium and vitamin E were able to alleviate oxidative stress and liver function damage due to the consumption of maize naturally contaminated with mycotoxins.     

猪日粮中酵母硒应用的研究进展

酵母硒是饲料中优质的有机硒源,较无机硒具有更高的吸收率与生物安全性,可提高猪的生长、成活率和繁殖性能,而且可提高肉品质和营养价值。作者综述了酵母硒在猪日粮中的应用研究进展。