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111.
Kanae SHIOKAWA Chandika D. GAMAGE Nobuo KOIZUMI Yoshihiro SAKODA Kenta SHIMIZU Yoshimi TSUDA Kumiko YOSHIMATSU Jiro ARIKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):221-230
The applicability of the recombinant LipL32 for serodiagnosis of leptospiral infection in field rodents was
assessed in this study. An immunodominant region of LipL32 was determined by monoclonal antibodies, and then,
truncated LipL32 (tLipL32) was designed to contain the region (87–188th amino acid). The tLipL32 was compared
between two recombinant expression hosts Escherichia coli and Pichia
pastoris in ELISA. With field rat sera, tLipL32 expressed by P. pastoris
(tLipL32p) had high antigenicity without background reactions, while tLipL32 expressed by E.
coli (tLipL32e) showed high background reactions, which were reduced by pre-adsorption of sera with
E. coli. To evaluate tLipL32-ELISA, field rat sera were tentatively divided into a
Leptospira infection positive (12 sera) and a negative group (12 sera) based on the results
from flaB gene PCR of kidney samples and WB with whole Leptospira cell.
Consequently, the sensitivity of tLipL32p-ELISA for field rat sera was 83% . A similar result was obtained
from tLipL32e-ELISA with adsorbed sera, (92%). However, sensitivity of tLipL32e-ELISA using sera without an
adsorption treatment was 50%. Regardless of the expression host, tLipL32-ELISA had 100% specificity and
sensitivity in experimentally infected laboratory rats. These results suggest that recombinant LipL32
expressed by P. pastoris is more applicable for serodiagnosis in field rats due to a lack of
background reaction. 相似文献
112.
Expression dynamics of bovine MX genes in the endometrium and placenta during
early to mid pregnancy
Takahiro SHIROZU Keisuke SASAKI Manabu KAWAHARA Yojiro YANAGAWA Masashi NAGANO Nobuhiko YAMAUCHI Masashi TAKAHASHI 《The Journal of reproduction and development》2016,62(1):29-35
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has
antiviral activity. MX has at least two isoforms, known as MX1 and
MX2, in mammals. Moreover, bovine MX1 has been found to have alternative
splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is
temporarily produced from the conceptus before implantation and induces MX expression in the
endometrium. However, the expression dynamics of MX after implantation are not clear. In the
present study, we investigated the expression of MX1-a, MX1B and
MX2 in the endometrium and placenta before and after implantation along with the expression
of IFN-α, type I receptors (IFNAR1 and IFNAR2) and
interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were
divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples
were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P).
Although all the MX expressions were significantly higher in the IC and C at days 14–18,
presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C
and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC.
RT-PCR indicated IFNAR1, IFNAR2, IRF3 and
IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the
MX genes are affected by the type I IFN pathway during pregnancy and are involved in an
immune response to protect the mother and fetus. 相似文献
113.
This study sought to determine whether an increase in resistance of Rhodococcus equi to the antibiotics rifampin and erythromycin occurred over a 10-year period. This was carried out by the use of E test strips for rifampin and erythromycin to determine the MIC (minimum inhibitory concentration) values of Rhodococcus equi to this combination of antibiotics.The findings of this study indicated that there was an increase in resistance of Rhodococcus equi to rifampin and erythromycin over the 10-year period. The MIC for rifampin increased from 0.081 μg/ml in 1996 to 0.187 μg/ml in 2006 and from 0.258 μg/ml for erythromycin during the years prior to 2000 to 0.583 μg/ml in 2006.This finding suggests that there may be a problem in the treatment of Rhodococcus equi infections in foals in the future, particularly as the number of drugs available for treatment of Rhodococcus equi infection is limited because of the intracellular capabilities of this bacterium. Antibiotics used in its treatment have to be able to penetrate the polysaccharide cell wall of Rhodococcus equi as well as the alveolar macrophages in which the bacterium is capable of surviving. 相似文献
114.
以4个引种燕麦(Avena sativa)为典型代表,对其不同生育时期根、茎、叶中的C、N、P含量及其化学计量学特征进行测定,探讨不同生育时期燕麦C、N、P元素含量及其化学计量比的变化规律,为燕麦饲草的科学收获提供理论依据。结果表明:燕麦全株C、N、P含量分别为322.30~333.97、17.42~75.62、2.74~5.42 mg·g-1,燕麦根C、N、P含量分别为298.42~317.92、11.47~73.71、2.82~3.42 mg·g-1,燕麦茎C、N、P含量分别为311.25~338.86、10.15~75.16、2.44~5.06 mg·g-1,燕麦叶C、N、P含量分别为330.80~372.47、30.64~113.80、2.59~8.65 mg·g-1;各器官间C、N、P含量表现为叶>茎>根。此外,燕麦各器官C、N、P含量的积累过程具有一定季节特征,C含量积累过程受生育时期影响较小,表现出较强的稳定性;而N和P含量的积累过程受生育时期影响较大,其在拔节期~抽穗期均... 相似文献
115.
为加强兽药检验检测机构能力建设,进一步提升检测技术水平,组织开展了全国省级兽药检验机构磺胺间甲氧嘧啶钠注射液含量测定的能力比对。依据《中国兽药典》2020年版一部附录0701电位滴定法与永停滴定法以及中国合格评定国家认可委员会(CNAS)规定的程序进行本次能力比对。分别采用单因子方差分析法和Ss≤0.3σ准则对测试样品进行均匀性检验,采用t检验方法和■准则对样品进行稳定性考察,采用Z比分数评价各参加实验室的测试结果。参加本次能力比对的36家兽药检测实验室中,33家结果为满意,满意率91.7%。 相似文献
116.
117.
土质边坡稳定安全系数的计算值主要与采用的简化计算方法和土工参数有关。采用正交试验法计算分析了不同的计算方法、材料参数、水位及其相关荷载、地震作用等对边坡安全系数计算值的影响,进而对设计中的计算方法和材料参数提出了一些有益的建议,并提出了在工程运行管理中应尽量避免低水位或水位骤降情况的意见,为土石坝类工程的设计与运行管理提供了重要参考。 相似文献
118.
119.
The study in molecular morphology is given with a highresolution Atomic Force Microscope AFM.IPC-208B.By taking TiN thim film prepared by magnerton sputtering method and polymide(PI) fibre for examples,the preferenthal growing plme of TiN thin film,the atomic arranges of TiN thin film on the preferential growing plme and the surficial micro-structure can be ascertained form the three-dimensional images obtamed by AFM.IPC-208B.These experiments not only identify small structures of the materials,but also affirm that AFM.IPC-208B holds the precision of atomic level and potential application in micro-structure field,at the same time it establishs the groundwork for the application in micro-process kingdom. 相似文献
120.
A video Monitor &Control system of tunnel based on DSP/BIOS is proposed,which is different from traditional video Monitor & Control system.It uses DSP to process image,and uses enhanced video input processor to qcquire image.This system satisfies all requirements of video supervision,and is a low cost system.It has a good application foreground.The system has been confirmed as a good veracity and practicability system through testing in the Zhongliang Mountain tunnel of Chongqing. 相似文献