Pesticide exposure assessment for surface waters in the EU. Part 1: Some comments on the current procedure

In 2001, the European Commission introduced a risk assessment project known as FOCUS (FOrum for the Coordination of pesticide fate models and their USe) for the surface water risk assessment of active substances in the European Union. Even for the national authorisation of plant protection products (PPPs), the vast majority of EU member states still refer to the four runoff and six drainage scenarios selected by the FOCUS Surface Water Workgroup. However, our study, as well as the European Food Safety Authority (EFSA), has stated the need for various improvements. Current developments in pesticide exposure assessment mainly relate to two processes. Firstly, predicted environmental concentrations (PECs) of pesticides are calculated by introducing model input variables such as weather conditions, soil properties and substance fate parameters that have a probabilistic nature. Secondly, spatially distributed PECs for soil–climate scenarios are derived on the basis of an analysis of geodata. Such approaches facilitate the calculation of a spatiotemporal cumulative distribution function (CDF) of PECs for a given area of interest and are subsequently used to determine an exposure concentration endpoint as a given percentile of the CDF. For national PPP authorisation, we propose that, in the future, exposure endpoints should be determined from the overall known statistical PEC population for an area of interest, and derived for soil and climate conditions specific to the particular member state. © 2016 Society of Chemical Industry     

Thoracoscopic pericardiotomy as a palliative treatment in a cow with pericardial lymphoma

A 5-year-old Holstein cow, pregnant with a valuable calf, was presented with signs of heart failure (tachycardia, peripheral edema, and distended jugular veins) related to pericardial lymphoma and associated cardiac tamponade. In addition, pleural effusion was present in both hemithoraces. Medical treatment, which consisted of repeated pericardiocenteses, placement of indwelling pleural catheters, administration of intravenous fluid therapy, antibiotics and anti-inflammatory drugs, was ineffective in controlling recurrence of clinical signs despite a temporary improvement. A standing thoracoscopic pericardiotomy was performed in an attempt to reduce clinical signs of heart failure and to prolong life. Clinical signs of heart failure abated and no recurrence was seen. Standing thoracoscopic pericardiotomy along with possible corticosteroids can be recommended as palliative treatment in an effort to extend life for reproductive performance in genetically valuable animals.     

基于生物酶法的酰基化桑椹花青素的制备与特性

为尽可能减少花青素的降解,提高其稳定性,采用生物酶法,对桑椹花青素进行酰基化修饰,并与非酰基化花青素进行对比研究.运用单因素试验筛选脂肪酶、反应溶剂和酰基供体,分析对花青素酰基转化率的影响.确定酰基化反应的优化条件为南极假丝酵母脂肪酶为酰基化催化酶、吡啶为催化反应溶剂、苯甲酸甲酯为酰基供体,酰基化效果最好,转化率最大为...     

Genetic architecture of plant height in maize phenotype‐selected introgression families

This study aimed at developing, characterizing and evaluating two maize phenotypic‐selected introgression libraries for a collection of dominant plant height (PHT)‐increasing alleles by introgressing donor chromosome segments (DCS) from Germplasm Enhancement of Maize (GEM) accessions into elite inbred lines: PHB47 and PHZ51. Different backcross generations (BC₁‐BC₄) were developed and the tallest 23 phenotype‐selected introgression families (PIFs) from each introgression library (PHB47 or PHZ51) were selected for single nucleotide polymorphism genotyping to localize DCS underlying PHT. The result shows that most PIFs carrying DCS were significantly (α = 0.01) taller than the respective recurrent parent. In addition, they contained larger donor genome proportions than expected in the absence of selection or random mating across all BC generations. The DCS were distributed over the whole genome, indicating a complex genetic nature underlying PHT. We conclude that our PIFs are enriched for favourable PHT‐increasing alleles. These two libraries offer opportunities for future PHT gene isolation and allele characterization and for breeding purposes, such as novel cultivars for biofuel production.     

Isolation and structure elucidation of highly antioxidative 3,8″-linked biflavanones and flavanone-C-glycosides from Garcinia buchananii bark

The aim of this study was to identify antioxidants from Garcinia buchananii bark extract using hydrogen peroxide scavenging and oxygen radical absorbance capacity (ORAC) assays. LC-MS/MS analysis, 1D- and 2D-NMR, and circular dichroism (CD) spectroscopy led to the unequivocal identification of the major antioxidative molecules as a series of three 3,8″-linked biflavanones and two flavanone-C-glycosides. Besides the previously reported (2R,3R,2″R,3″R)-naringenin-C-3/C-8″ dihydroquercetin linked biflavanone (GB-2; 4) and (2R,3S,2″R,3″R)-manniflavanone (3), whose stereochemistry has been revised, the antioxidants identified for the first time in Garcinia buchananii were (2R,3R)-taxifolin-6-C-β-D-glucopyranoside (1), (2R,3R)-aromadendrin-6-C-β-D-glucopyranoside (2), and the new compound (2R,3S,2″S)-buchananiflavanone (5). The H?O? scavenging and the ORAC assays demonstrated that these natural products have an extraordinarily high antioxidative power, especially (2R,3S,2″R,3″R)-manniflavanone (3) and GB-2 (4), with EC?? values of 2.8 and 2.2 μM, respectively, and 13.73 and 12.10 μmol TE/ μmol. These findings demonstrate that G. buchananii bark extract is a rich natural source of antioxidants.     

东南亚猪的遗传育种

简要地回顾了东南亚猪近50年来的猪品种改良历程,重点阐述了泰国正大集团在猪育种上的发展过程,分析了现行的猪繁育体系结构.对猪育种的基本原则、性状遗传相关的影响、杂种优势的利用、育种与环境的关系、市场需求导向等进行了讨论.在总结作者从事养猪生产50余年经验的基础上,对目前东南亚猪的育种提出了有参考价值的建议.     

Alterations in serum parathyroid hormone and electrolyte concentrations and urinary excretion of electrolytes in horses with induced endotoxemia

Hypocalcemia and hypomagnesemia are common in horses with sepsis and endotoxemia. We hypothesize that endotoxemia triggers a systemic inflammatory response that results in hypocalcemia and hypomagnesemia. The goal of this study was to determine the effect of endotoxin (lipopolysaccharide [LPS]) administration to healthy horses on serum parathyroid hormone (PTH), ionized calcium (Ca2+) and total calcium (tCa), ionized magnesium (Mg2+) and total magnesium (tMg), phosphate (Pi), potassium (K+), sodium (Na+), chloride (Cl-), and insulin concentrations, and on the urinary excretion of these electrolytes. Twelve mares were infused with Escherichia coli LPS (30 ng/kg/h i.v.) for 1 hour. Six mares were infused with saline (controls). In LPS-infused horses, heart rate increased significantly from (mean +/- SD) 40.0 +/- 1.3 to 70.0 +/- 9.0 beats/min, respiratory rate from 12.7 +/- 1.0 to 21.1 +/- 3.0 breaths/min, body temperature from 37.4 +/- 0.3 to 38.9 +/- 0.6 degrees C, and tumor necrosis factor-alpha concentrations from 6.6 +/- 3.5 to 507 +/- 260 pg/mL (P < .05). White blood cell count decreased significantly from 7570 +/- 600 to 1960 +/- 560 cells/ microL. Serum concentrations of Ca2+ decreased from 6.5 +/- 0.3 to 6.0 +/- 0.3 mg/dL, of Mg2+ from 0.53 +/- 0.06 to 0.43 +/- 0.04 mM, of tMg from 0.78 +/- 0.05 to 0.62 +/- 0.08 mM, of K+ from 4.3 +/- 0.4 to 3.0 +/- 0.5 mEq/L, and of Pi from 3.4 +/- 0.5 to 1.7 +/- 0.5 mg/dL (all P < .05). PTH increased significantly from 1.3 +/- 0.4 to 6.0 +/- 5.2 pM; however, in some horses (n=2), PTH did not increase despite hypocalcemia. Insulin increased significantly from 9.4 +/- 3.6 to 50.5 +/- 9.6 microIU/mL (n=3). Urinary fractional excretion of Ca2+ decreased significantly from 4.7 +/- 1.4 to 1.7 +/- 1.2%, of Mg2+ from 36.6 +/- 6.5 to 11.7 +/- 7.3%, and of K+ from 37.9 +/- 11.3 to 17.7 +/- 6.2%. Fractional excretion of Pi increased from 0.02 +/- 0.02 to 0.14 +/- 0.07% and of Na+ from 0.26 +/- 0.13% to 1.2 +/- 0.5%. No changes were found in serum tCa, Na+, and Cl- concentrations. In conclusion, endotoxemia in horses resulted in electrolyte abnormalities that included hypocalcemia, hypomagnesemia, hypokalemia, hypophosphatemia, and increased serum PTH and insulin concentrations.