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Relapse of childhood AML1-ETO (AE) acute myeloid leukemia is the most common cause of treatment failure. Optimized minimal residual disease monitoring methods is required to prevent relapse. In this study, we used next-generation sequencing to identify the breakpoints in the fusion gene and the DNA-based droplet digital PCR (ddPCR) method was used for dynamic monitoring of AE-DNA. The ddPCR technique provides more sensitive and precise quantitation of the AE gene during disease progression and relapse. Quantification of the AE fusion gene by ddPCR further contributes to improved prognosis. Our study provides valuable methods for dynamic surveillance of AE fusion DNA and assistance in determining the prognosis.  相似文献   
613.
Previous studies on Bacillus thuringiensis (Bt) resistance in the diamondback moth (DBM) Plutella xylostella have often focused on receptor proteins in the gut. In recent years, many studies have indicated that insect resistance to Bt is related to the immune system. Moreover, our group demonstrated that the expression of peptidoglycan recognition protein (PGRP) genes, which are located upstream of the insect humoral immune system signalling pathway, is significantly different between Cry1Ac-resistant and Cry1Ac-susceptible strains of DBM. Thus, whether antimicrobial peptides (AMPs), which are the major downstream effectors of the insect humoral immune system signalling pathway, are also related to the resistance of DBMs to Bt is a question worthy of in-depth study. In the present study, we sought to (a) clone the CDS of AMP genes expressed in DBMs and (b) explore the effect of the cloned AMPs on the biological characteristics and Bt resistance of DBMs. Here, we revealed three kinds of AMPs (PxDef, PxMor and PxCec), and each of their full-length CDSs was cloned. The recombinant PxDef, PxMor or PxCec proteins, which were expressed in a prokaryotic expression system, have a significant protective effect on DBMs in response to the complex microbial environment of the outside world but have no significant effect on the resistance of DBMs to Cry1Ac toxin. We believe that AMPs are not suitable as the primary entry point for studying the relationship between the immune system of DBMs and their resistance to Bt. This result will enable investigation of breakthrough ideas for further elucidating the mechanism of Bt impact on the insect immune system.  相似文献   
614.
Inflorescence ontogeny and morphology of the det mutant of Pisum sativum L. were investigated using scanning electron microscopy. This mutation causes the production of a limited number of axillary flowers followed by the formation of an apparent terminal flower slightly offset from the vertical. Our study indicates that the apparent terminal flower arises from an axillary meristem. The terminal meristem senesces and differentiates hairs, forming a rudimentary stub in the same manner as axillary meristems of conventional (Det) and det plants. Thus the dramatic effect of the det gene on inflorescence architecture results from early apical arrest rather than conversion of the terminal meristem to a flower as implied by the symbol det. This mutant will be valuable in elucidating regulation of apical arrest.  相似文献   
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Intrathymic maturation of T lymphocytes is characterized byvariable expression of O-linked Galß1,3GalNAc glycansreactive with peanut agglutinin (PNA) lectin. Recent studieson human thymocytes show that conversion from PNA+ to PNAphenotype is correlated with increased expression of  相似文献   
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