Sentinel lymph node mapping by near‐infrared fluorescence imaging and contrast‐enhanced ultrasound in healthy dogs

Sentinel lymph node (SLN) mapping is a valuable and crucial diagnostic procedure in staging malignancies. We compared two non‐invasive techniques, near‐infrared (NIR) fluorescence imaging and contrast‐enhanced ultrasound (CEUS), to identify the SLNs in three superficial anatomical regions in an animal model. Six healthy laboratory dogs were included in a proof‐of‐concept trial. A NIR fluorescent dye (Indocyanine Green) and microbubbles (Sonovue) were consecutively injected subdermally in the Inguinal, axillary and popliteal region to map the SLNs. Transcutaneous NIR fluorescence imaging identified SLNs in 17 out of a total of 18 occasions. CEUS identified SLNs in all regions (18/18). Whereas NIR fluorescence imaging performed better in the visualization of the afferent lymphatic tract, CEUS demonstrated different filling patterns of the SLNs, a feature potentially critical for the concept of SLN mapping in cancer patients. Both NIR fluorescence imaging and CEUS are safe, non‐invasive, practical and accurate methods to perform real‐time transcutaneous SLN mapping with potential in a clinical setting.     

Genetic Analysis and Mapping of TWH Gene in Rice Twisted Hull Mutant

A mutant with twisted hulls was found in a breeding population of rice (Oryza sativa L.). The mutant shows less grain weight and inferior grain quality in addition to twisted hulls. Genetic analysis indicated that the phenotype of mutant was controlled by a single recessive gene (temporarily designated as TWH). To map the TWH gene, an F2 population was generated by crossing the twh mutant to R725, an indica rice variety with normal hulls. For bulked segregant analysis, the bulk of mutant plants was prepared by mixing equal amount of plant tissue from 10 twisted-hull plants and the bulk of normal plants was obtained by pooling equal amount tissue of 10 normal-hull plants. Two hundred and seven pairs of simple sequence repeat (SSR) primers, which are distributed on 12 rice chromosomes, were used for polymorphism analysis of the parents and the two bulks. The TWH locus was initially mapped close to the SSR marker RM526 on chromosome 2. Therefore, further mapping was performed using 50 pairs of SSR primers around the marker RM526. The TWH was delimited between the SSR markers RM14128 and RM208 on the long arm of chromosome 2 at the genetic distances of 1.4 cM and 2.7 cM, respectively. These results provide the foundation for further fine mapping, cloning and functional analysis of the TWH gene.     

不同水分环境下玉米叶面积QTL定位及候选基因分析

玉米叶面积的大小及分布特征不仅影响其光合效率、蒸腾速率,而且与其耐旱性、耐密性、抗倒伏性及产量形成紧密相关。深入剖析不同水旱环境下玉米不同生育时期不同叶位叶面积的分子遗传机理对玉米耐旱高产新品种的选育具有重要意义。本研究以构建的2套F_2∶3群体为试材,在8种水分环境下,采用复合区间作图法（CIM）和基于混合线性模型的复合区间作图法（MCIM）对玉米相应叶（V₁₈时期第10片叶、R₁时期穗三叶）叶面积进行单环境和多环境联合QTL分析;参考玉米基因组B73 RefGen_v3挖掘稳定表达的QTLs （sQTLs）区间内的候选基因,并对其进行功能分析。结果表明,采用CIM法,单环境下2个生育时期2套F_2∶3群体间总共定位到了7个玉米相应叶叶面积QTLs,主要受显性（81.0%）、部分显性（14.3%）和超显性（4.7%）等遗传效应的调控,其中在干旱环境下定位到了5个QTLs。采用MCIM法,在2套F_2∶3群体间总共检测到6个相应叶叶面积的联合QTLs,其中1个表现为显著的QTL与环境的互作（QTL×E, Bin 2.08~2.09）,1对QTLs （Bin 1.08~1.10与 Bin 2.08~2.09）参与了显著的加性与加性（AA）上位性互作。结合CIM和MCIM法进一步分析在2套F_2∶3群体间检测到了6个sQTLs,其分别位于Bin 1.08~1.10、Bin 2.08~2.09、Bin 4.08~4.09、Bin 6.05、Bin 8.03和Bin 10.03处,并在这些sQTLs区间内确定了12个玉米叶发育相关候选基因。采用生物信息学,总共收集了75个玉米叶发育相关候选基因,通过系统进化树分析表明,这些候选基因划分为3大进化分支,且上述检测到的12个候选基因分布于这3大进化分支上。这些结果为系统地解析玉米不同生育时期不同水旱环境下相应叶叶面积的分子遗传机理提供理论依据,检测到的sQTLs可作为叶面积改良的重要染色体区段,检测到的候选基因为其进一步克隆、功能分析及育种应用提供了信息参考。     

面向对象多层次多尺度分割的农用大棚类型信息提取

为对不同农用大棚类型信息进行识别分类和精细化提取,以内蒙古河套灌区不同大棚类型为研究对象,基于Sentinel-2A卫星数据,采用面向对象结合多层多尺度分割技术和阈值分类方法,对大棚类型信息进行提取并对最终提取结果展开精度评价和分析研究。首先利用尺度参数估计（Estimation of Scale Parameter2, ESP2）方法进行了分层分割并优选出最佳分割尺度,在各层最优分割尺度上进行光谱、指数、几何、纹理等特征的提取与优化,获取最优特征组合;然后运用多层多尺度分割阈值分类方法提取不同大棚类型信息。结果表明不同大棚类型信息总体精度达94.8%,kappa系数达0.93。其中：塑料大棚的制图精度和用户精度分别为95.3%和96.6%;单屋面温室大棚制图精度和用户精度分别为88.5%和92.6%。基于多层多尺度分割分类的信息提取方法分别考虑了不同地物最优分割尺度,在不同地物各自的最优分割尺度上提取其信息,以抑制过度分割或亚分割现象,从而降低错分或漏分。因此,高分辨率卫星数据与面向对象多层多尺度分割分类的信息提取方法能够有效提高大棚类型信息提取精度,且能为地物信息精细提取技术体系提供一定参考思路。     

Identification of QTLs related to sugar and organic acid composition in melon using near-isogenic lines

The soluble sugar and organic acid composition of melon (Cucumis melo L.) fruit flesh has become a major focus of plant breeding worldwide in an attempt to improve taste. Thus, sugar and organic acid profiles were characterized using near-isogenic lines (NILs) derived from the Spanish cultivar Piel de Sapo (PS) and the exotic Korean accession Shongwan Charmi (PI 161375). Fruits were cultivated in only one environment. These data were used to map 60 quantitative trait loci (QTLs): 18 for individual sugars, eight for sucrose equivalents, five for the glucose-to-fructose ratio, seven for the total sugar content and 21 for organic acids. Within the QTLs that were associated with the sugar profile, 27 defined the sugar content: eight for fructose, six for glucose, four for sucrose, and nine for sucrose equivalents. Although increased sweetness of selected NILs compared with the parental PS was achieved by an increased glucose or fructose content, only glucose heritability was above 0.5. A total of 21 QTLs (two with positive effects and nineteen with detrimental effects compared with the PS levels) controlled the organic acid profile: l-glutamic, ascorbic and succinic acids (the principal ones) and fumaric, citric, oxalacetic, and isocitric acids. The levels of sugars imparted by the PI 161375 introgression frequently decreased the score grades given to NILs by consumers. Within the 32 QTLs mapped for sensory traits, 27 were associated with lower scores in taste (nine QTLs), sweetness (eight QTLs) or global quality appreciation (nine QTLs); two with increased fruit sourness or sweetness and three with increased fruit bitterness. The QTLs defined herein may assist breeders to understand the overall organoleptic balance (sweetness, sourness, and umami taste) in melon fruit, particularly those located within linkage groups III, V, VI, and VIII to XI.     

Bibliometric Profile of an Agbioscience Research Enhancement Grant Program

This study is a bibliometric analysis of journal articles generated from an intramural grant program in the agbiosciences. Using citation analysis and bibliometric mapping, the study analyzes 515 journal articles published from 1999 to 2017. Results show the growth of journal article output, identify the major research fields and topics, describe national and international authorial and institutional collaborations, and quantify the performance and impact of the article output. The grant program’s journal article output presents a multi-disciplinary range of scholarly publications that reflect the disciplines of The Ohio State University’s College of Food, Agricultural, and Environmental Sciences, which houses the grant program.     

一个调控水稻叶绿素合成基因wl-1的精细定位

为改良优异两系不育系株1S (Z1S)的株型特征,利用甲基磺酸乙酯(EMS)诱变技术处理株1S (Z1S),得到一个苗期为白条纹的突变体,命名为wl-1。以该突变体与粳稻品种日本晴杂交,得F1种子,进而获得自交F2群体。遗传分析表明wl-1受单个隐性基因控制。利用图位克隆技术将wl-1初定位于水稻第3号染色体上RM15851和RM15880两个标记之间。进一步扩大遗传定位群体,最终将wl-1精细定位于标记inedl3和indel4之间的122 kb区域内。生物信息学分析表明该区域有12个ORF。对这12个ORF编码区逐个测序分析表明,其第10个ORF (LOC-03g52170),编码4-羟基-3-甲基丁-2-烯基二磷酸还原酶的第2个外显子上的第165位碱基处存在1个碱基A替换为T的突变。基因表达分析表明,在幼苗期与野生型株1S相比,突变体中LOC-03g52170的表达量显著低于相应的野生型;同时突变体中叶绿素合成相关基因、光合作用相关基因以及叶绿体发育相关基因的表达量发生了显著变化。对叶色基因wl-1 (LOC-03g52170)的挖掘,有利于进一步阐释叶绿体和叶绿素合成的生物学机理,同时为水稻高光效育种提供理论和技术支撑。     

Genetic Analysis and Preliminary Mapping of a Highly Male-Sterile Gene in Foxtail Millet（Setaria italica L.Beauv.） Using SSR Markers

Breeding of male-sterile lines has become the mainstream for the heterosis utilization in foxtail millet,but the genetic basis of most male-sterile lines used for the hybrid is still an area to be elucidated.In this study,a highly male-sterile line Gao146A was investigated.Genetic analysis indicated that the highly male-sterile phenotype was controlled by a single recessive gene a single recessive gene.Using F 2 population derived from cross Gao146A/K103,one gene controlling the highly male- sterility,tentatively named as ms1,which linked to SSR marker b234 with genetic distance of 16.7 cM,was mapped on the chromosome VI.These results not only laid the foundation for fine mapping of this highly male-sterile gene,but also helped to accelerate the improvement of highly male-sterile lines by using molecular marker assisted breeding method.     

结球甘蓝抽薹性遗传规律和QTL定位分析

以早抽薹‘S-1’与晚抽薹‘G-1’为亲本,构建F1、BC1、BC2和F2群体,采用植物数量性状主基因 + 多基因混合遗传模型分析法对结球甘蓝抽薹性状进行遗传分析,并采用SLAF-BSA方法对抽薹时间进行QTL定位分析。结果显示,结球甘蓝抽薹性状是由2对加性—显性—上位性主基因 + 加性—显性多基因遗传控制;主基因 + 多基因平均遗传率是93.41%。共检测到2个QTL,分别为2号染色体上的2.31 ~ 3.09 Mb和33.57 ~ 34.40 Mb,总长度为1.61 Mb。