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Background: Parthenocarpy is an important trait for yield and quality in many plants. But due to its complex interactions with genetic and physiological factors, it has not been adequately understood and applied to breeding and production. Finding novel and effective quantitative trait loci (QTLs) is a critical step towards understanding its genetic mechanism. Cucumber (Cucumis sativus L.) is a typical parthenocarpic plant but the QTLs controlling parthenocarpy in cucumber were not mapped on chromosomes, and the linked markers were neither user-friendly nor confirmed by previous studies. Hence, we conducted a two-season QTL study of parthenocarpy based on the cucumber genome with 145 F2:3 families derived from a cross between EC1 (a parthenocarpic inbred line) and 8419 s-1 (a non-parthenocarpic inbred line) in order to map novel QTLs. Whole genome re-sequencing was also performed both to develop effective linked markers and to predict candidate genes. Results: A genetic linkage map, employing 133 Simple Sequence Repeats (SSR) markers and nine Insertion/Deletion (InDel) markers spanning 808.1 cM on seven chromosomes, was constructed from an F2 population. Seven novel QTLs were identified on chromosomes 1, 2, 3, 5 and 7. Parthenocarpy 2.1 (Parth2.1), a QTL on chromosome 2, was a major-effect QTL with a logarithm of odds (LOD) score of 9.0 and phenotypic variance explained (PVE) of 17.0 % in the spring season and with a LOD score of 6.2 and PVE of 10.2 % in the fall season. We confirmed this QTL using a residual heterozygous line97-5 (RHL97-5). Effectiveness of linked markers of the Parth2.1 was validated in F3:4 population and in 21 inbred lines. Within this region, there were 57 genes with nonsynonymous SNPs/InDels in the coding sequence. Based on further combined analysis with transcriptome data between two parents, CsARF19, CsWD40, CsEIN1, CsPPR, CsHEXO3, CsMDL, CsDJC77 and CsSMAX1 were predicted as potential candidate genes controlling parthenocarpy. Conclusions: A major-effect QTL Parth2.1 and six minor-effect QTLs mainly contribute to the genetic architecture of parthenocarpy in cucumber. SSR16226 and Indel-T-39 can be used in marker-assisted selection (MAS) of cucumber breeding. Whole genome re-sequencing enhances the efficiency of polymorphic marker development and prediction of candidate genes. [ABSTRACT FROM AUTHOR]

Objective: To analyze the expression level of miR-429 in patients with acute lymphoblastic leukemia(ALL) and its clinical prognostic value., Methods: One hundred and Twenty-six patients with ALL treated in our hospital from April 2016 to February 2018 were selected, and 100 healthy persons in the same period were selected as control group. Bone marrow mononuclear cells were collected. The expression level of miR-429 in bone marrow mononuclear cells was detected by RT-PCR, and the correlation of miR-429 expression with clinical characteristics and therapeutic efficacy was analyzed. Kaplan-Meier method and multi-factorial Cox regression model were used to analyze the correlation between the level of microRNA-429 and the prognosis of ALL patients., Results: The relative level of miR-429 in ALL patients was 2.47±0.07, which was signifi-cantly higher than that in control group (P<0.05). The level of miR-429 significantly correlated with the leucocyte level（r=0.994）, LDH（r=0.992）, the ratio of bone marrow primordial cells（r=0.995） and risk grade of ALL patients（r=0.991). The level of miR-429 not correlate with the age, sex, Hb level, Plt level and immunophenotype of ALL patients (P>0.05). The level of miR-429 was not significantly different between CR patients and control group (P>0.05); the level of miR-429 in PR patients was higher than that in control group and CR patients (P<0.05). The level of miR-429 in NR patients was higher than that in other groups (P<0.05). Kaplan-Meier survival analysis showed that the overall survival rate of ALL patients with low expression of miR-429 was better than that of ALL patients with high expression of miR-429 (P<0.05). Univariate Cox regression analysis showed that leukocyte level, ratio of bone marrow primordial cells, Hb and LDH level, risk grading and miR-429 were the factors influencing overall survival rate in ALL patients (P<0.05). Multivariate Cox regression analysis showed that leukocyte level, ratio of bone marrow primordial cells, risk grading, and miR-429 were the factors influencing overall survival rate (P<0.05)., Conclusion: The expression of miR-429 is high in ALL patients, which closely relates to the curative effect and pro-gnosis of ALL patients, and can be used as a reference index for evaluation of clinical prognosis of ALL patients.