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991.
Neda N. Moghadam Pia Mai Thorshauge Torsten N. Kristensen Nadieh de Jonge Simon Bahrndorff Henrik Kjeldal 《Fly》2018,12(1):1-12
Physiological responses to changes in environmental conditions such as temperature may partly arise from the resident microbial community that integrates a wide range of bio-physiological aspects of the host. In the present study, we assessed the effect of developmental temperature on the thermal tolerance and microbial community of Drosophila melanogaster. We also developed a bacterial transplantation protocol in order to examine the possibility of reshaping the host bacterial composition and assessed its influence on the thermotolerance phenotype. We found that the temperature during development affected thermal tolerance and the microbial composition of male D. melanogaster. Flies that developed at low temperature (13°C) were the most cold resistant and showed the highest abundance of Wolbachia, while flies that developed at high temperature (31°C) were the most heat tolerant and had the highest abundance of Acetobacter. In addition, feeding newly eclosed flies with bacterial suspensions from intestines of flies developed at low temperatures changed the heat tolerance of recipient flies. However, we were not able to link this directly to a change in the host bacterial composition. 相似文献
992.
Anna Staffas Marina Burgos da Silva Ann E. Slingerland Amina Lazrak Curtis J. Bare Corey D. Holman Melissa D. Docampo Yusuke Shono Benjamin Durham Amanda J. Pickard Justin R. Cross Christoph Stein-Thoeringer Enrico Velardi Jennifer J. Tsai Lorenz Jahn Hillary Jay Sophie Lieberman Odette M. Smith Marcel R.M. van den Brink 《Cell host & microbe》2018,23(4):447-457.e4
993.
Variations in the major surface proteins (HBsAg) of hepatitis B virus (HBV) have been implicated in the high rate of reinfection in HBV-infected recipients of orthotopic liver transplantations (OLT). Sera from 6 OLT patients positive for HBsAg and from 3 recipients negative for it prior to transplantation were analyzed over several years, and 39 HBsAg sequences were compared. Despite anti-HBs immunoprophylaxis resulting in the disappearance of HBsAg, HBV DNA was detectable by a sensitive nested PCR in almost all sera. In 1 patient, a significant temporary shift in HBV subtypes was observed, indicating a mixed infection or the presence of multiple HBV populations in this patient; this was also true for other patients. Amino acid substitutions compared to wild-type HBV subtypes in 7 patients and variations within patients in 5 patients were detectable over time; the escape mutation at amino acid position 145 was detected in 2 patients. Our data suggest that the high rate of reinfection in OLT recipients seems not to be associated with specific sequence variations in the major HBs gene, but shows a remarkable inter- and intraindividual variability. Obviously, no correlation between heterogeneity in this gene and clinical outcome was present.The following investigators and institutions were members of the Liver Transplantation Group: U. Beuers, M. Bilzer, W. Caselmann, A. Gerbes, R. Hoffmann, C. Jung, G.R. Pape (Medical Department II), J. Briegel, J. Groh, M. Haller (Institute of Anesthesiology), H.J. Krämling, H. Rauh and M. Stangl (Department of Surgery). 相似文献
994.
van Dobbenburgh J. Onno Kasbergen Carina Slootweg Piet J. Ruigrok Tom J. C. van Echteld Cees J. A. 《Molecular and cellular biochemistry》1996,163(1):247-252
This study was undertaken to validate the potential of 31P magnetic resonance spectroscopy (MRS) as a noninvasive alternative for transvenous endomyocardial biopsy in detecting cardiac allograft rejection. Donor hearts from either Lewis rats (L) or Brown-Norway rats (BN) were transplanted into the neck of L rats resulting in a non-rejecting group L-L and a rejecting group L-BN. L-L and L-BN rats were serially studied by means of 31P MRS from postoperatine day 1–8. In addition, rejection was confirmed by histology. A similar, marked decrease in phosphocreative/-adenosinetriphosphate (PCr/ATP) ratio from day 1–3 was observed in both L-L and L-BN hearts. This ratio levelled off on postoperative day 3 and remained depressed on subsequent postoperative days in both groups, although histology showed an increase in the severity of rejection in L-BN. However, the PCr signal/noise ratio in L-BN started to decrease after day 4, coinciding with the histologic evidence of severe rejection (score IV), whereas in L-L hearts (score 0) this ratio remained unaltered until day 8. Since high-energy phosphate metabolism is affected by the unloaded status of the heterotopically transplanted heart, irrespective of rejection, the PCr/ATP ratio appears not to be a specific marker for the detection of acute rejection in this model. In contrast, the PCr S/N ratio appears to be a specific and sensitive marker of acute rejection, but only in a late, severe stage. 相似文献
995.
硬骨鱼类体细胞核移植的研究 总被引:6,自引:0,他引:6
本文用不同属、科、目的硬骨鱼类作材料进行体细胞核移植研究。鲫鱼(Carassiusauratus)、鲮鱼(Cirrhinusmolitorella)和尼罗罗非鲫(Tilapianilotica)的体细胞核(头肾细胞)移植到鲤鱼(Cyprinuscarpio)的成熟去核卵中,通过继代核移植,在鲫鱼体细胞核和鲤鱼去核卵的属间组合中,获得发育到血液循环期的幼鱼;在鲮鱼体细胞核和鲤鱼去核卵的亚科间组合中,获得发育到心脏跳动期的晚期胚胎;在尼罗非鲫体细胞核和鲤鱼去枚卵的目间组合中,获得发育到肌肉效应期的胚胎。由于是直接用成鱼体细胞核作供核体进行核移植,因而能够克服供体鱼和受体鱼不同步产卵的困难。实验结果表明,这对进行硬骨鱼类核质杂交研究无疑是一种简便而又有效的方法。 相似文献
996.
将稳定转染了大鼠酪氨酶羟化酶(Tyrosinehydroxylase,TH)基因的大鼠成肌细胞移植于帕金森病大鼠模型的纹状体,进行基因治疗研究。RT-PCR和免疫组织化学检测都证明转基因细胞可在纹状体内存活并表达TH,动物的不对称旋转行为明显改善,而且疗效可维持半年以上。 相似文献
997.
海马内移植颈上神经节组织改善穹窿-海马伞横切大鼠的记忆功能 总被引:3,自引:0,他引:3
38只Wistar大鼠双侧穹窿-海马伞损伤后.以被动回避反应为指标观察到记忆明显受损,与损伤前相比,有记忆动物自65.3%降至13.6%,两者差别非常显著。于穹窿-海马伞损伤后记忆丧失动物(n=15)自体一侧分离出颈上神经节(SCG),切为2-3块并在室温下孵育于20—50μg/ml2.5sNGF中1—2h,而后移植于自体双侧海马背侧,移植4周后观察到动物记忆明显恢复,恢复记忆的动物数占73.3%。在行为实验基础上应用荧光组化方法检查了移植细胞成活情况并测量了海马内去甲肾上腺素(NA)的含量。移植后2周海马内NA含量比损伤组有明显上升。移植后一个月,可见部分移植细胞成活并有神经纤维生长。实验表明.穹窿-海马伞损伤大鼠海马内自体移植SCG,通过神经递质的局部补充对动物丧失的记忆能力具有一定改善作用。 相似文献
998.
Maria S. Gonzlez Omar J. Rimoldi Rodolfo R. Brenner 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1995,110(4)
The function of Triatoma infestans very-high-density lipoprotein (VHDL) as a free fatty acid transport protein was analyzed. Lipophorin (HDLp) and VHDL are the unique hemolymphatic proteins able to transport free fatty acids (FFA). The transfer of this lipid species between HDLp and VHDL was studied using 14C-palmitic acid-labeled VHDL or 14C-palmitic acid-labeled HDLp as donor substrate and the same unlabeled lipoproteins as acceptor substrate. The VHDL is more effective as acceptor of 14C-FFA from HDLp rather than donor of 14C-FFA to HDLp. When 14C-palmitic acid-labeled VHDL was incubated with either fat body or testicle, it was observed that the 14C-palmitic acid was taken up by both tissues and incorporated into their lipid components. 相似文献
999.
Utilization of molasses for the production of fat by an oleaginous yeast,Rhodotorula glutinis IIP-30
Von W. Johnson Manjit Singh Virender S. Saini Dilip K. Adhikari Venkatrao Sista Natwarsinh K. Yadav 《Journal of industrial microbiology & biotechnology》1995,15(1):1-4
Summary
Rhodotorula glutinis is known to produce fat when cultivated under nitrogen-limiting conditions. Economically, molasses is an ideal substrate, however, due to the presence of nitrogen in molasses, the lipid yield obtained is much lower than that obtained from glucose or sucrose. Higher yields were obtained using molasses in a fed batch fermentation supplemented with glucose or sucrose during the lipid accumulation phase. The fatty acids profile of the lipids thus produced, using a very simple and economical medium, was similar to that obtained from glucose and sucrose. 相似文献
1000.
FactorsAffectingElectro-FusionandElectro-ActivationInSerialNuclearTransplantationInGoat(Carpahircus)EmbryoWANGYu-ge(王玉阁);ZOUX... 相似文献