Capnographic documentation of nasoesophageal and nasogastric feeding tube placement in dogs

Objective: To evaluate the ability of capnography to document proper placement of nasoesophageal (NE) and nasogastric (NG) feeding tubes. This study was conducted in 3 phases. Phase I of this study was designed in order to test the efficacy of capnography to distinguish placement of a feeding tube in the alimentary tract versus the respiratory tract. Phase II was designed in order to document that carbon dioxide (CO₂) could be measured through a polyvinyl chloride (PVC) feeding tube. Phase III was performed in order to evaluate the technique of continuous monitoring during insertion of the feeding tube into the esophagus and stomach as would be performed during a clinical‐tube placement. Design: Prospective study. Setting: Research laboratory. Animals: 24 adult dogs. Interventions: In Phase I, sedated dogs were instrumented with an intratracheal catheter and an 8 French feeding tube placed nasally into the distal esophagus and later advanced into the stomach. In Phase II, dogs were anesthetized and an 8 French feeding tube was placed down the endotracheal tube, then into the esophagus and later advanced into the stomach. In Phase III, sedated dogs were instrumented with an 8 French feeding tube inserted intranasally and then advanced to the level of the nasopharynx, distal esophagus and, lastly, the stomach. Fluoroscopy was used in order to determine location of the feeding tube. Measurements and main results: Phase I measurements included respiratory rate and CO₂ from the trachea, esophagus, and stomach and pH of gastric fluid sample. Phase II measurements included respiratory rate and CO₂ from the endotracheal tube, feeding tube in the endotracheal tube, feeding tube in the distal esophagus, and feeding tube in the stomach. Phase III data collection included respiratory rate and CO₂ as the tube was passed through the nasal cavity, nasopharynx, esophagus and stomach. Phase I fluid samples were collected from 5 of the 9 dogs and had pH values from 1.68 to 4.20. In both phases, values for the respiratory rate and CO₂ from the esophagus and stomach were 0 ± 0, significantly lower (P < 0.001) than the values from the trachea. In Phase II, there was no significant difference between the respiratory rates (P = 0.886) and CO₂ (P = 0.705) readings obtained from the endotracheal tube compared to readings from the feeding tube in the endotracheal tube. In Phase III, there was a significant difference (P < 0.001) between the respiratory rates and CO₂ readings obtained from the nasal cavity and the nasopharynx when compared to those readings obtained from the esophagus and stomach. Measurement of CO₂ and respiratory rate resulted in a reading of 0 every time the feeding tube was in the esophagus or stomach. Conclusions: Capnography may be used in order to detect airway placement of NE and NG tubes.     

The integration and insertion site of GbVe1 gene in the genome of transgenic cotton (Gossypium hirsutum)

[Objective] The aim of this study was to obtain the flanking sequences of T-DNA in the transgenic cotton containing a GbVe1 over-expression cassette. [Method] The T-DNA insertion copy number in the transgenic GbVe1 cotton was analyzed by southern blot. Flanking sequences of the transgenic lines with putative single T-DNA insertion copy were obtained using high-efficiency Thermal asymmetric interlaced polymerase chain reaction (hiTAIL-PCR). The T-DNA insertion sites were further confirmed by PCR with specific primers. [Result] RB-flanking sequences (119-1 018 bp) and LB-flanking sequences (243-516 bp) were obtained from three transgenic lines with low copy number of T-DNA insertion. The AT content was more than 63% in these flanking sequences. A same single insertion site in the intron of Gohir.D01G157600.1 was found in the two transgenic lines 7/100826-152 and 12/100826-393, while two separated insertion sites, one also in the intron of Gohir.-D01G157600.1 and the other in the intergenic region of A12 chromosome, were found in the transgenic line 1/w-ch14. A deletion of 21 bp was found in the insertion site in the intron of Gohir.D01G157600.1. The T-DNA insertion in the intron of Gohir.D01G157600.1 was further confirmed by the specific PCR. [Conclusion] The flanking sequences of T-DNA in the transgenic GbVe1 cotton were obtained and the specific transformation event in the intron of Gohir.D01G157600.1 was further confirmed by PCR.     

一个新的水稻生育期延迟T-DNA插入突变体

从水稻突变体库中筛选到一个生育期延迟突变体,主要表现为生育期延迟、植株矮化、叶色变深、叶角张大、根系变短。遗传分析表明该突变体受1对隐性单基因控制。对突变体及其后代分离群体做Basta抗性检测,证实该突变体是由T-DNA插入引起的,突变性状与T-DNA共分离。PCR和Southern杂交结果进一步证实了上述观点。该材料可用于插入座位的基因克隆和生育期调控机理的研究。     

蔬菜移栽机斜插夹钵式取投苗装置研制

针对目前中国蔬菜穴盘苗全自动移栽作业,取投苗装置复杂、易失败等问题,该文设计了一种斜插夹钵式取投苗装置。通过对取投苗装置原理的分析,运用投影法对装置进行设计,确定了装置各结构参数。为保证装置具有良好的取投苗效果,对苗盘倾斜角度及苗夹入穴参数进行了设计,同时分析其运动过程,对比仿真轨迹曲线和试验实际轨迹曲线,验证了方案的可行性。综合考虑影响取投苗效果的因素,以取投苗成功率作为取投苗效果评价指标,选取弹簧刚度系数、主动杆转速、苗盘倾斜角度为试验因素,进行正交试验。试验结果表明:在给定因素水平下,当弹簧刚度系数为500 N/m,主动杆转速为12 r/min,苗盘倾斜角度为45°时,取投苗效果最佳,此时基质破碎率为3.13%,钵苗脱落率为2.43%,取投苗成功率为94.44%,装置的可靠性较高。研究结果可为全自动化移栽研究提供参考。     

Insertion site of FLAG on foot-and-mouth disease virus VP1 G-H loop affects immunogenicity of FLAG

The G-H loop of the foot-and-mouth disease virus(FMDV) virion contains certain dominant immunogenic epitopes, as well as an arginine-glycine-aspartic acid(RGD) motif that is recognized by cell surface integrin receptors. Previous experiments indicate that it is critical to maintain virus structural integrity when inserting an exogenous epitope into the surface of an FMDV structural protein. However, it remains to be determined how factors such as different insertion positions affect interactions among the virus, cells and host immune system. In this study, one infectious c DNA clone of the swine FMDV Cathay topotype strain O/CHA/90 was constructed. Then, a FLAG marker(DYKDDDDK) was inserted upstream(–4) or downstream(+10) of the RGD motif to generate tagged viruses vFLAG-O/CHA/90 or vO/CHA/90-FLAG, investigating the possibility of expressing foreign antigen and effect on its immunogenicity. Compared to the parental virus, both tagged viruses exhibited similar plaque phenotypes, suckling mouse pathogenicity and antigenicity. Additionally, the FLAGtag insertion position did not change the use of integrin-mediated cell entry by the tagged viruses. Interestingly, both tagged vaccines protected pigs against challenge with the parental virus O/CHA/90 and induced immune responses against FMDV in BALB/c mice and pigs, but only vaccination with vFLAG-O/CHA/90 generated anti-FLAG antibodies. Our findings demonstrated that two sites(RGD–4 and RGD+10) tolerated the insertion of an exogenous gene in the swine FMDV O/CHA/90 strain. However, only RGD–4 was a novel and appropriate inserting site which could tolerate exogenous FLAG. The resultant tagged virus is a promising candidate for FMD vaccine which can be differentiating infected from vaccinated animals(DIVA).     

Morphological Basis of Resistance in Cotton to the WhiteflyBemisia Tabaci

The morphological basis of resistance to the whiteflyBemisia tabaci Genn. (Aleyrodidae: Hemiptera) was studied. The plant characters examined were leaf area, thickness of leaf lamina, hair density, hair length, angle of insertion of leaf hair, and density of gossypol glands. Hair density and leaf thickness were positively correlated with the population ofB. tabaci, and a positive correlation was obtained between the adult whitefly population and gossypol glands on stem internodes. Cotton genotype USA-22 (sparsely hairy) was found to be more tolerant toB. tabaci than was genotype USA-13 (velvety hairy). The use of thinner and glabrous leaved cotton varieties is suggested to minimize the whitefly menace in cotton.     

一例金毛犬胫骨斜骨折的髓内针逆向插入法联合钢丝内固定术治疗

通过对一例金毛犬胫骨斜骨折进行内固定术,详细介绍了髓内针逆向插法联合钢丝进行内固定术的手术要点,为同行进行犬胫骨斜骨折内固定术治疗提供参考。     

Wide mapping of a T-DNA insertion site in oilseed rape using bulk segregant analysis and comparative mapping

Doubled haploid oilseed rape lines segregating for a transgene inducing herbicide resistance (bar gene) were investigated for the wide mapping of the T-DNA insertion site. Bulk segregant analysis using presence/absence and intensity polymorphisms between the bulks, as well as comparative mapping with a linkage group deriving from another cross, led to the identification of 11 random amplified polymorphic DNA (RAPD) markers tightly or loosely linked to the bar gene. Ten RAPD loci out of 11 were located on the same side of the bar locus, strongly suggesting that the T-DNA integrated in a telomeric or subtelomeric position. The eleventh RAPD marker exhibited a strong segregation distortion, which could be the result of a heteroduplex formation. Comparison of the linkage groups obtained from the two crosses showed different recombination rates between markers, possibly reflecting differences in parental genetic backgrounds. Consequences and potential applications in transgene dispersal safety assessment studies are discussed.     

数据等概率分档统计插入排序算法

提出了一种按数据等概率分档的排序算法，此算法应用现代统计学的一些知识和技巧，结合传统的排序算法，对具有一般分布的数据进行排序，使排序的运算量为O（n），达到了排序运算量的下限，实验表明，在n较大时此算法效率要优于现有的同类排序算法。     

水稻拔节至抽穗期叶片着生状态的数学模型模拟比较研究

[目的]为了寻找描述水稻叶片着生状态特性的最佳数学模型,更好地揭示水稻生长过程中株形特性。[方法]以杂交稻品种B优827为试验对象,用Logistic、渐进回归、二次曲线、S曲线、逻辑斯蒂和Gauss 6个方程分别对水稻叶片着生角度进行拟合,并比较了不同方程的拟合效果。[结果]6个方程对B优827的叶片着生角度都能拟合且达到极显著水平(P<0.01)。相比之下,Gauss模型拟合决定系数最大。[结论]Gauss模型拟合效果最好,能更好地反映品种的叶片着生状态特性。