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Yizhi Jiang Dongping Huang Yuji Kondo Miao Jiang Zhenni Ma Lu Zhou Jian Su Xia Bai Changgeng Ruan Zhaoyue Wang Lijun Xia 《Journal of cellular and molecular medicine》2020,24(7):4356-4361
Hereditary thrombotic thrombocytopenic purpura (TTP) is an autosomal recessive thrombosis disorder, caused by loss-of-function mutations in ADAMTS13. Mutations in the CUB domains of ADAMTS13 are rare, and the exact mechanisms through which these mutations result in the development of TTP have not yet been fully elucidated. In this study, we identified two novel mutations in the CUB domains in a TTP family with an acceptor splice-site mutation (c.3569−1, G>A, intron 25) and a point missense mutation (c.3923, G>A, exon 28), resulting in a glycine to aspartic acid substitution (p.G1308D). In vitro splicing analysis revealed that the intronic mutation resulted in abnormal pre-mRNA splicing, and an in vitro expression assay revealed that the missense mutation significantly impaired ADAMTS13 secretion. Although both the patient and her brother displayed significantly reduced ADAMTS13 activity and increased levels of ultra-large VWF (ULVWF) multimers in plasma, only the female developed acute episodes of TTP. Our findings indicate the importance of the CUB domains for the protein stability and extracellular secretion of ADAMTS13. 相似文献
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Liu Y Wang M Xue M Li Y Li X Ruan J Liu K 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,873(1):41-50
The structural elucidation of metabolites of penehyclidine in rats, a novel anti-cholinergic drug, by the method of liquid chromatography-electrospray ionization mass spectrometry, gas chromatography-mass spectrometry with electron impact ion source and stable isotope ion cluster was described. Identification and elucidation of the phase I and phase II metabolites were performed by comparing the daughter ion pairs of stable isotope cluster, changes of the protonated molecular masses, full scan MS(n) spectra and retention times with those of the parent drug, penehyclidine and penehyclidine deuterium-labeled. Penehyclidine was easily biotransformed by the pathways of oxidative, hydroxylated, methoxylated and phase II conjugated reactions to form several metabolites that retained the some features of the parent molecules. Twelve metabolites (penehyclidine monoxide, hydroxypenehyclidine, penehyclidine dioxide, hydroxypenehyclidine monoxide, dihydroxypenehyclidine, dihydroxypenehyclidine (position isomer), dihydroxypenehyclidine monoxide, trihydroxypenehyclidine, methoxypenehyclidine dioxide, dimethoxypenehyclidine, trihydroxymethoxypenehyclidine and glucuronide conjugated hydroxypenehyclidine) were identified. The results from electrospray ion and electron impact ion data with the stable isotope cluster showed the qualitative differences in the mass spectral patterns, suggesting that these technologies should be used in parallel to ensure comprehensive metabolites detection and characterization. The described method has wide applicability to rapidly screen and provide structural information of metabolites. 相似文献
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The solenopsis mealybug, Phenacoccus solenopsis, has been recently recognized as an aggressively invasive pest in China, and is now becoming a serious threat to the cotton industry in the country. Thus, it is necessary to investigate the molecular mechanisms employed by cotton for defending against P. solenopsis before the pest populations reach epidemic levels. Here, we examined the effects of exogenous jasmonic acid (JA), salicylic acid (SA), and herbivory treatments on feeding behavior and on development of female P. solenopsis. Further, we compared the volatile emissions of cotton plants upon JA, SA, and herbivory treatments, as well as the time-related changes in gossypol production and defense-related genes. Female adult P. solenopsis were repelled by leaves from JA-treated plant, but were not repelled by leaves from SA-treated plants. In contrast, females were attracted by leaves from plants pre-infested by P. solenopsis. The diverse feeding responses by P. solenopsis were due to the difference in volatile emission of plants from different treatments. Furthermore, we show that JA-treated plants slowed P. solenopsis development, but plants pre-infested by P. solenopsis accelerated its development. We also show that P. solenopsis feeding inhibited the JA-regulated gossypol production, and prevented the induction of JA-related genes. We conclude that P. solenopsis is able to prevent the activation of JA-dependent defenses associated with basal resistance to mealybugs. 相似文献
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Jun-Jie Zhang Bing-Zhong Ren Xiao-Hua Yuan Lian-Sheng Zang Chang-Chun Ruan Guang-Zhi Sun Xi-Wen Shao 《BioControl》2014,59(2):159-166
The striped stem borer, Chilo suppressalis (Walker), is one of the most economically important rice pests worldwide. However, biological control of this pest using natural-enemy insects has been rarely documented to date. With the objective of screening suitable candidate species for controlling the striped stem borer, we investigated the effect of the age of host eggs on the host selection and suitability by four indigenous Trichogramma species on their native host, C. suppressalis. The results indicated that the differently aged eggs of C. suppressalis were all accepted by T. japonicum, T. dendrolimi and T. chilonis, and there was a clear tendency to parasitize older eggs less under no-choice and choice conditions. The number of parasitized host eggs by T. ostriniae also decreased with the increasing host age in the no-choice test, but more 2-day-old host eggs were parasitized in the choice test. When 0-, 2-day-old eggs were offered, T. dendrolimi, T. japonicum and T. chilonis exhibited similar parasitism ability, whereas T. ostriniae appeared to have a stronger ability to attack the older host eggs (4-day-old). Trichogramma japonicum developed and emerged on parasitized C. suppressalis eggs of all ages tested, while showing a better adaptation to younger host eggs with significantly faster developmental time, higher survival and more female progeny on 0-day-old eggs. No adults for each of the other three Trichogramma species emerged from parasitized 4-day-old host eggs, and they had similar developmental time, survival and female progeny on parasitized 0-, 2-day-old host eggs with an exception of female progeny for T. chilonis. On 0-day-old host eggs, T. japonicum developed faster and T. ostriniae had lower progeny survival than the other three Trichogramma species evaluated, respectively. The current study provides useful information to select suitable Trichogramma species for controlling the striped stem borer, C. suppressalis. 相似文献
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We consider a two-dimensional model of cell-to-cell spread of HIV-1 in tissue cultures, assuming that infection is spread
directly from infected cells to healthy cells and neglecting the effects of free virus. The intracellular incubation period
is modeled by a gamma distribution and the model is a system of two differential equations with distributed delay, which includes
the differential equations model with a discrete delay and the ordinary differential equations model as special cases. We
study the stability in all three types of models. It is shown that the ODE model is globally stable while both delay models
exhibit Hopf bifurcations by using the (average) delay as a bifurcation parameter. The results indicate that, differing from
the cell-to-free virus spread models, the cell-to-cell spread models can produce infective oscillations in typical tissue
culture parameter regimes and the latently infected cells are instrumental in sustaining the infection. Our delayed cell-to-cell
models may be applicable to study other types of viral infections such as human T-cell leukaemia virus type 1 (HTLV-1).
Received: 18 November 2000 /
Published online: 28 February 2003
RID="*"
ID="*" Research was partially supported by the NSERC and MITACS of Canada and a start-up fund from the College of Arts and
Sciences at the University of Miami. On leave from Dalhousie University, Halifax, Nova Scotia, Canada.
Current address: Department of Mathematics, Clarke College, Dubuque, Iowa 52001, USA
Key words or phrases: HIV-1 – Cell-to-cell spread – Time delay – Stability – Hopf bifurcation – Periodicity 相似文献
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