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81.
It has been demonstrated that neural precursor cell expressed developmentally downregulated protein (NEDD) plays crucial roles in tumorigenesis and may serve as potential biomarkers in cancer diagnosis and prognosis. However, few studies systematically investigated the expression of NEDD family members in acute myeloid leukaemia (AML). We systemically determined the expression of NEDD family members in AML and determined their clinical significance. We identified that NEDD9 expression was the only member among NEDD family which was significantly increased in AML. NEDD9 overexpression was more frequently classified as FAB-M4/M5 (= 0.008 and 0.013, respectively), hardly as FAB-M2/M3. Moreover, NEDD9 overexpression was significantly associated with complex karyotype and TP53 mutation. The significant association between NEDD9 overexpression and survival was also observed in whole-cohort AML and non-M3 AML patients. Notably, AML patients with NEDD9 overexpression may benefit from hematopoietic stem cell transplantation (HSCT), whereas those cases without NEDD9 overexpression did not. Finally, a total of 822 mRNAs and 31 microRNAs were found to be differentially expressed between two groups. Among the microRNAs, miR-381 was also identified as a microRNA that could direct target NEDD9. Taken together, our findings demonstrated that NEDD9 overexpression is associated with genetic abnormalities as well as prognosis and might act as a potential biomarker guiding the choice between HSCT and chemotherapy in patients with AML after achieving complete remission.  相似文献   
82.
Molecular Breeding - The stem color of young mung bean is a very useful tool in germplasm identification. Flowering time and plant height (PH) are known to be strongly correlated with crop adaption...  相似文献   
83.
The current study was undertaken to investigate anticancer activity of coumestrol phytoestrogen against human skin cancer. MTT assay was performed for cell viability assessment and clonogenic assay for cell colony formation assessment. Apoptosis was analysed by Annexin V/FITC staining, AO/EB staining and western blotting assays. Effects on the m-TOR/PI3K/AKT signalling pathway were investigated by western blotting. Results indicated that coumestrol induced significant toxicity in human skin cancer cells in contrast to mouse skin cancer cells. The proliferation rate in normal skin cells remained almost intact. Annexin V-FITC and AO/EB staining assays indicated coumestrol induced cytotoxicity in skin cancer cells is mediated through apoptosis stimulation. The apoptosis in skin cancer cells was mediated through caspase-activation. Cell migration and invasion was inhibited by coumestrol in human skin cancer cells via inhibition of MMP-2 and MMP-9 expressions. Moreover, m-TOR/PI3K/AKT signalling pathway in SKEM-5 cells was blocked by coumestrol.  相似文献   
84.
竹叶菜的组织培养研究   总被引:1,自引:0,他引:1  
竹叶菜为百合科鹿药属一种多年生草本植物,因做菜口感好,且营养丰富、药用价值高而成为深受人们喜爱的一种野生蔬菜.有关竹叶菜及其同属的组织培养研究均未见报道.本文以竹叶菜的顶芽为外植体,通过器官发生途径,初步探索了竹叶菜的组织培养技术,结果表明:芽诱导的合适培养基为:MS +6-BA 1.5 +NAA 0.05+0.6%琼脂+3%蔗糖;芽继代培养的合适培养基为:MS+6-BA 1.2 +NAA 0.05 +0.6%琼脂+3%蔗糖;无菌小苗生根的合适培养基为:MS+ IAA 1.5+ NAA 0.2+ 0.6%琼脂+3%蔗糖.为竹叶菜今后较大规模地栽培或生产提供种苗及技术贮备,为实现竹叶菜资源的可持续性开发利用奠定了基础.  相似文献   
85.
86.
The live morphology, infraciliature, and morphogenesis of a new oxytrichid ciliate, Notohymena apoaustralis n. sp. collected from a freshwater pond in Qingdao (Tsingtao), China, were studied in vivo and after protargol impregnation. Notohymena apoaustralis n. sp. is characterized as follows: undulating membranes in Notohymena‐pattern; cortical granules yellow‐green, grouped around the marginal cirri and dorsal bristles, and in short irregular rows elsewhere in the cell; single contractile vacuole positioned at anterior 1/3 of the body length; two macronuclear nodules and one micronucleus; about 39 adoral membranelles; 18 frontoventral transverse cirri in typical Oxytricha‐pattern; one right and one left marginal row, almost confluent posteriorly; dorsal ciliature in typical Oxytricha‐pattern; 8–10 caudal cirri arranged in three rows, one each at the posterior end of dorsal kineties 1, 2, and 4, indistinguishable from marginal cirri in life. The morphogenetic process in N. apoaustralis n. sp. is consistent with that of the type species, Notohymena rubescens Blatterer and Foissner, 1988. Phylogenetic analyses based on small subunit rDNA sequence data suggest a sister relationship between N. apoaustralis n. sp. and Paraurostyla weissei, which cluster in a clade with Rubrioxytricha ferruginea.  相似文献   
87.
88.
The affinity digestion process for cellulase purification consisting of binding to amorphous cellulose, and amorphous cellulose hydrolysis in the presence of dialysis (Morag et al., 1991), was optimized to obtain high activity recoveries and consistent protein recoveries in the isolation of Clostridium thermocellum cellulase. Experiments were conducted using crude supernatant prepared from C. thermocellum grown on either Avicel or cellobiose. While no difference was observed between Avicel-grown or cellobiose-grown cellulase in the adsorption step, differences were observed during the hydrolysis step. The optimal amorphous cellulose loading was found to be 3 mg amorphous cellulose per milligram supernatant protein. At this loading, 90–100% of activity in the crude supernatant was adsorbed. Twenty-four-hour incubation with the amorphous cellulose during the adsorption stage was found to result in maximal and stable adsorption of activity to the substrate. By fitting the adsorption data to the Langmuir model, an adsorption constant of 410 L/g and a binding capacity of 0.249 g cellulase/g cellulose were obtained. The optimal length of time for hydrolysis was found to be 3 hr for cellulase purified from Avicel cultures and 4 hr for cellulase purified from cellobiose cultures. These loadings and incubation times allowed for more than 85% activity recovery.  相似文献   
89.
Melanaphis sacchari causes serious damage to sorghum (Sorghum bicolor (L.) Moench) growth, development and productivity in many countries. A dominant gene (RMES1) conferring resistance to M. sacchari has been found in the grain sorghum variety Henong 16 (HN16), but fine mapping of the RMES1 locus remains to be reported. In this study, genetic populations segregating for RMES1 were prepared with HN16 and BTx623 as parental lines. The latter had been used for sorghum genome sequencing but was found to be susceptible to M. sacchari in this work. A total of 11 molecular markers were mapped to the short arm of chromosome 6 harboring RMES1. The closest markers flanking the RMES1 locus were Sb6m2650 and Sb6rj2776, which delimited a chromosomal region of about 126 kb containing five predicted genes. The utility of the newly identified DNA markers for tagging RMES1 in molecular breeding of M. sacchari resistance, and further efforts in cloning RMES1, are discussed.  相似文献   
90.
1,3-Butadiene (BD) has been classified as a human carcinogen, group I; however, the relationship between polymorphisms of glutathione S-transferases that metabolize BD and chromosomal damage is not clear. The present study used sister chromatid exchange (SCE) and cytokinesis-block micronucleus (CBMN) assays to detect chromosomal damage in peripheral lymphocytes of 44 BD-exposed workers and 39 non-exposed healthy controls. PCR and PCR-RFLP were employed to detect three known glutathione S-transferase polymorphisms GSTT1, GSTM1, and GSTP1 (Ile105Val). The data demonstrated that the micronucleus (CBMN) frequency in BD-exposed workers was significantly higher than that in controls (frequency ratio (FR) = 1.48, 95% CI: 1.14–1.91, P < 0.01), and the CBMN frequency was higher in workers exposed to higher cumulative BD levels (FR = 1.70, 95% CI: 1.28–2.27, P < 0.01). However, differences in SCE frequency were not observed (FR = 1.14, 95% CI: 0.81–1.61, P > 0.05). Among exposed workers, chromosomal damage was related to BD exposure levels (FR = 1.35, 95% CI: 1.02–1.80, P < 0.05); age, older workers exhibited higher MN frequencies than younger workers (FR = 1.45, 95% CI: 1.14–1.84, P < 0.05); and years of work, those with more years of work exhibited higher MN frequencies than those with fewer years (FR = 1.40, 95% CI: 1.10–1.77, P < 0.05). Multivariate Poisson regression analysis showed that those who carried GSTM1 (?) (FR = 1.48, 95% CI: 1.14–1.92) or GSTT1 (?) (FR = 1.42, 95% CI: 1.10–1.83) genotypes, and especially those who carried both (FR = 2.10, 95% CI: 1.43–3.09) exhibited significantly higher MN frequencies than those carrying GSTM1 (+), GSTT1 (+) genotypes or their combination. The GSTP1 Val genotype did not affect MN frequency (P > 0.05). Our results suggested that higher levels of BD exposure in the workplace resulted in increased chromosomal damage, and that polymorphisms in GSTT1 and GSTM1 genes might modulate the genotoxic effects of BD exposure. Furthermore, the GSTT1 and GSTM1 polymorphisms exhibited an additive effect. Finally, urinary DHBMA was found to provide a biomarker that correlated with airborne BD levels.  相似文献   
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