Genome-wide characterization and expression profiling of the NAC genes under abiotic stresses in Cucumis sativus.

The NAC (standing for no apical meristem [NAM], Arabidopsis transcription activation factor [ATAF] and cup-shaped cotyledon [CUC]) proteins pertain to one of the plant-specific transcription factor families that play important roles in plant development, abiotic stress resistance and signalling transduction. In the present study, the genomic features of the NAC genes in cucumber were analysed in depth using in silico tools. To reveal a tissue-specific, abiotic stress and hormone-responsive expression profile of CsNAC genes, RT-qPCR was performed under different treatments. Phylogenetic analyses and genome-wide annotation indicated that 82 high-confidence CsNAC genes were clustered into 13 sub-groups with uneven distribution in the cucumber genome. Furthermore, the CsNAC genes exhibited different tissue-specific expression patterns in 10 tissues under normal growth conditions, while 13 (16%) and 28 (34%) genes displayed preferential expression in roots and flowers, respectively. Moreover, CsNAC genes were more sensitive to salinity than other stresses; however, their responses were relatively rapid and transient to nutrition deprivation. Several CsNAC genes, including CsNAC35, which is an orthologue of the known stress-responsive Arabidopsis RD26, were identified as highly responsive to abiotic stresses and hormones. Overall, our findings revealed the genomic landscape and expression profiling of the CsNAC genes in response to multiple stresses and hormones, offering clues for further function analyses and molecular breeding.

Leaf Volatile Compounds and Associated Gene Expression during Short-Term Nitrogen Deficient Treatments in Cucumis Seedlings.

Nitrogen (N) is an important macronutrient for plant growth and development, but the regulatory mechanism of volatile compounds in response to N deficiency is not well understood, especially in cucumber, which consumes excessive N during growth. In this study, the major volatile compounds from cucumber leaves subjected to N deficiency were analyzed by GC-MS. A total of 24 volatile components were identified including 15 aldehydes, two ketones, two alkenes, and five other volatile compounds in 9930 leaves. Principal component analysis using volatile compounds from cucumber leaves provided good separation between N-sufficient and N-deficient treatments. The main volatiles in cucumber leaves were found to be C6 and C9 aldehydes, especially (E)-2-hexanal and (E,Z)-2,6-nonadienal. (E)-2-hexanal belonged to the C6 aldehyde and was the most abundant compound, whereas (E,Z)-2,6-nonadienal was the chief component of C9 aldehydes. During N-deficient treatment, short-chain volatile content was significantly improved at 5 day, other volatiles displayed significant reduction or no significantly changes in all sampling points. Improvement of short-chain volatiles was confirmed in the six other inbred lines at 5 day after N-deficient treatments. The expression analysis of 12 cucumber LOX genes and two HPL genes revealed that CsLOX19, CsLOX20, and CsLOX22 had common up-regulated expression patterns in response to N-deficient stress in most inbred lines; meanwhile, most sample points of CsHPL1 also had significant up-regulated expression patterns. This research focused on the relationship between volatiles in cucumber and different nitrogen environments to provide valuable insight into the effect of cultivation and management of the quality of cucumber and contributes to further research on volatile metabolism in cucumber.

Effect of nitrogen deficiency on ascorbic acid biosynthesis and recycling pathway in cucumber seedlings.

L-Ascorbic acid (AsA, ascorbate) is one of the most abundant natural antioxidants, and it is an important factor in the nutritional quality of cucumber. In this work, key enzymes involved in the ascorbic acid biosynthesis and recycling pathway in cucumber seedlings under nitrogen deficiency were investigated at the levels of transcription and enzyme activity. The activities of myo-inositol oxygenase (MIOX) and transcript levels of MIOXs increased dramatically, while the activities of ascorbate oxidase (AO) and glutathione reductase (GR) and transcript levels of AOs and GR2 decreased significantly in N-limited leaves, as did the ascorbate concentration, in nitrogen-deficient cucumber seedlings. The activities of other enzymes and transcript levels of other genes involved in the ascorbate recycling pathway and ascorbate synthesis pathways decreased or remained unchanged under nitrogen deficiency. These results indicate that nitrogen deficiency induced genes involved in the ascorbate-glutathione recycling and myo-inositol pathway in cucumber leaves. Thus, the AO, GR and MIOX involved in the pathways might play roles in AsA accumulation.

[Influence of the DNA integrity of optimized sperm on the embryonic development and clinical outcomes of in vitro fertilization and embryo transfer].

OBJECTIVE: To investigate the influence of the DNA integrity of optimized sperm on the embryonic development and clinical outcomes of in vitro fertilization and embryo transfer (IVF-ET). METHODS: This study included 605 cycles of conventional IVF-ET for pure oviductal infertility performed from January 1, 2013 to December 31, 2014. On the day of retrieval, we examined the DNA integrity of the sperm using the sperm chromatin dispersion method. According to the ROC curve and Youden index, we grouped the cycles based on the sperm DNA fragmentation index (DFI) threshold value for predicting implantation failure, early miscarriage, and fertilization failure, followed by analysis of the correlation between DFI and the outcomes of IVF-ET. RESULTS: According to the DFI threshold values obtained, the 605 cycles fell into four groups (DFI value < 5%, 5-10%, 10-15%, and ≥ 15%). Statistically significant differences were observed among the four groups in the rates of fertilization, cleavage, high-quality embryo, implantation, clinical pregnancy, early miscarriage, and live birth (P < 0.05), but not in the rates of multiple pregnancy, premature birth, and low birth weight (P > 0.05). DFI was found to be correlated negatively with the rates of fertilization (r = -0.32, P < 0.01), cleavage (r = -0.19, P < 0.01), high-quality embryo (r = -0.40, P < 0.01), clinical pregnancy (r = -0.20, P < 0.01), and live birth (r = -0.09 P = 0.04), positively with the rate of early miscarriage (r = 0.23, P < 0.01), but not with the rates of multiple pregnancy (r = -0.01, P = 0.83), premature birth (r = 0.04, P = 0.54), and low birth weight (r = 0.03, P = 0.62). CONCLUSION: The DNA integrity of optimized sperm influences fertilization, embryonic development, early miscarriage, and live birth of IVF-ET, but its correlation with premature birth and low birth weight has to be further studied.

[Values of the sperm deformity index, acrosome abnormity rate, and sperm DNA fragmentation index of optimized sperm in predicting IVF fertilization failure].

OBJECTIVE: To investigate the values of the sperm deformity index (SDI), acrosome abnormity rate (AAR), and DNA fragmentation index (DFI) of optimized sperm in the prediction of fertilization failure (fertilization rate < 25%) in conventional in vitro fertilization (IVF). METHODS: We selected 695 cycles of conventional IVF for pure oviductal infertility in this study, including 603 cycles of normal fertilization and 92 cycles of fertilization failure. On the day of oocyte retrieval, we examined sperm morphology, acrosome morphology, and DNA fragmentation using the Diff-Quik, PSA-FITC and SCD methods. We established the joint predictor (JP) by logistic equation and analyzed the values of different parameters in predicting fertilization failure with the receiver operating characteristic (ROC) curve. RESULTS: The fertilization rate was negatively correlated with SDI (r = - 0.07; P = 0.03), AAR (r = -0.49; P < 0.01), and DFI (r = -0. 21; P < 0.01). The SDI, AAR, and DFI in the normal fertilization group were 1.24 ± 0.20, (7.75 ± 2.28)%, and (7.87 ± 3.15)%, and those in the fertilization failure group were 1.42 ± 0.15, (12.02 ± 3.06)%, and (13.32 ± 4.13)%, respectively, all with statistically significant differences between the two groups (P < 0.05). SDI, AAR, and DFI were all risk factors of fertilization failure ( OR = 2.68, 14.11, and 3.85; P = 0.01, < 0.01, and < 0.01). The areas under the ROC curves for SDI, AAR, DFI, and JP were 0.651 ± 0.033, 0.895 ± 0.019, 0.789 ± 0.022, and 0.915 ± 0.017, respectively. According to the Youden index, the optimal cut-off values of SDI, AAR, and DFI obtained for the prediction of fertilization failure were approximately 1.45, 10%, and 12%. CONCLUSION: The SDI, AAR and DFI of optimized sperm are closely associated with the fertilization rate, and all have the value for predicting fertilization failure in IVF. The AAR is more valuable than the other single predictors, but JP is more effective than the AAR.

[Correlation of the DNA fragmentation index and malformation rate of optimized sperm with embryonic development and early spontaneous abortion in IVF-ET].

OBJECTIVE: To investigate the effects of the DNA fragmentation index (DFI) and malformation rate (SMR) of optimized sperm on embryonic development and early spontaneous abortion in conventional in vitro fertilization and embryo transfer (IVF-ET). METHODS: We selected 602 cycles of conventional IVF-ET for pure oviductal infertility that had achieved clinical pregnancies, including 505 cycles with ongoing pregnancy and 97 cycles with early spontaneous abortion. On the day of ovum retrieval, we examined the DNA integrity and morphology of the rest of the optimized sperm using the SCD and Diff-Quik methods, established the joint predictor (JP) by logistic equation, and assessed the value of DFI and SMR in predicting early spontaneous abortion using the ROC curve. RESULTS: The DFI, SMR, and high-quality embryo rate were (15.91±3.69)%, (82.85±10.24)%, and 46.53% (342/735) in the early spontaneous abortion group and (9.30±4.22)%, (77.32±9.19)%, and 56.43% (2263/4010) respectively in the ongoing pregnancy group, all with statistically significant differences between the two groups (P<0.05 ). Both the DFI and SMR were the risk factors of early spontaneous abortion (OR = 5.96 and 1.66; both P< 0.01). The areas under the ROC curve for DFI, SMR and JP were 0.893±0.019, 0.685±0.028, and 0.898±0.018, respectively. According to the Youden index, the optimal cut-off values of the DFI and SMR obtained for the prediction of early spontaneous abortion were approximately 15% and 80%. The DFI was correlated positively with SMR (r= 0.31, P<0.01) but the high-quality embryo rate negatively with both the DFI (r= －0.45, P<0.01) and SMR (r= －0.22, P<0.01). CONCLUSIONS: The DFI and SMR of optimized sperm are closely associated with embryonic development in IVF. The DFI has a certain value for predicting early spontaneous abortion with a threshold of approximately 15%, but SMR may have a lower predictive value.

[Overview of organic agriculture development.] / 有机农业发展概述.

This paper introduced the concepts of organic agriculture as defined by different international organizations, origin and theoretical development of organic agriculture, as well as its developing trajectory in China (i.e. a late start followed by rapid growth compared to developed countries). The differences between domestic and international organic agriculture were illustrated by scale, crop types, production standards, inputs and planting techniques. Constraints limiting improvements to organic agriculture in aspects of standards, technology, marketing, certification, environmental pollution, enterprise reputation, and national policies were discussed. Future directions and strategies for developing healthy organic agriculture in China were provided.

[A clinicopathologic and prognosis study of Epstein-Barr virus positive diffuse large B-cell lymphoma in west-southern China].

OBJECTIVE: To investigate the clinicopathologic features, immunophenotype, and the prognosis related factors of Epstein-Barr virus (EBV) positive diffuse large B-cell lymphoma (DLBCL) in west-southern China. METHODS: There were 42 cases of EBV+ DLBCL in a total 586 DLBCL, the clinical and pathologic profiles of these patients were evaluated. Immunohistochemical study and in situ hybridization (ISH) of EBER1/2 were performed on formalin fixed tissues by tissue chips. The prognosis related factors were analyzed. RESULTS: The median age of these 42 EBV+ DLBCL patients was 62.5 years. The male-to-female ratio was 2.23 : 1. The site of occurrence included lymph node (69.05%) and spleen, stomach, tonsil, nasal cavity and nasopharynx. The mostly common initial clinical presentations were non-specific symptoms, such as lymphadenopathy, splenomegaly, hepatomegaly, fever, and fatigue. Morphologically, the majority (90.48%, 38/42) were pleomorphic subtypes and only 4 cases (9.52%) were simplex subtypes. Immunophenotype showed non-GCB type of DLBCL was predominance (83.33%, 35/42) by Hans classification. The expression of CD30, CD5, BCL-2, P53 and NF-kappaB/ P65 were 52.38% (22/42), 54.76% (23/42), 54.76% (23/42), 87.5% (35/40) and 0% (0/40) respectively. Follow-up data was available in 23 (54.76%) patients, 14 (60.87%) patients died of the tumor. 5-years overall survival was 16.5%. The median survival time was 40 months. The expression of BCL-2, increased LDH level and starry-sky morphologic character were associated with a poor prognosis. CONCLUSION: EBV positive DLBCL is not uncommon. Most lesions locate in lymph nodes. Pleomorphic histologic subtype is predominant. The tumor has worse prognosis with increased LDH level, starry-sky morphologic character and BCL-2 expression.

Characterization and expression profiling of cucumber kinesin genes during early fruit development: revealing the roles of kinesins in exponential cell production and enlargement in cucumber fruit.

Rapid cell division and expansion in early fruit development are important phases for cucumber fruit yield and quality. Kinesin proteins are microtubule-based motors responsible for modulating cell division and enlargement. In this work, the candidate kinesin genes involved in rapid cell division and expansion during cucumber fruit development were investigated. The morphological and cellular changes during early fruit development were compared in four cucumber genotypes with varied fruit size. The correlation between the expression profiles of cucumber kinesin genes and cellular changes in fruit was investigated. Finally, the biochemical characteristics and subcellular localizations of three candidate kinesins were studied. The results clarified the morphological and cellular changes during early cucumber fruit development. This study found that CsKF2-CsKF6 were positively correlated with rapid cell production; CsKF1 and CsKF7 showed a strongly positive correlation with rapid cell expansion. The results also indicated that CsKF1 localized to the plasma membrane of fast-expanding fruit cells, that CsKF2 might play a role in fruit chloroplast division, and that CsKF3 is involved in the function or formation of phragmoplasts in fruit telophase cells. The results strongly suggest that specific fruit-enriched kinesins are specialized in their functions in rapid cell division and expansion during cucumber fruit development.

The expression profiling of the lipoxygenase (LOX) family genes during fruit development, abiotic stress and hormonal treatments in cucumber (Cucumis sativus L.).

Lipoxygenases (LOXs) are non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids and lipids to initiate the formation of a group of biologically active compounds called oxylipins. Plant oxylipins play important and diverse functions in the cells. In the current study, expression analysis during cucumber development using semi-quantitative RT-PCR revealed that 13 of 23 CsLOX genes were detectable, and were tissue specific or preferential accumulation. In total, 12 genes were found to be differentially expressed during fruit development and have different patterns of expression in exocarp, endocarp and pulp at day 5 after anthesis. The expression analysis of these 12 cucumber LOX genes in response to abiotic stresses and plant growth regulator treatments revealed their differential transcript in response to more than one treatment, indicating their diverse functions in abiotic stress and hormone responses. Results suggest that in cucumber the expanded LOX genes may play more diverse roles in life cycle and comprehensive data generated will be helpful in conducting functional genomic studies to understand their precise roles in cucumber fruit development and stress responses.

[Research on predicting modeling for chlorophyll contents of greenhouse tomato leaves based on multi-spectral imaging].

Traditional spectrum analysis technology has low accuracy for forecasting chlorophyll content of plants. Research based on 3CCD camera has the limitations of high cost and the number of sensitive wavelengths not adjustable. The present paper develops a new approach to forecasting the chlorophyll content of tomato leaves by the image gray value of the selected sensitive wavelengths (532, 610 and 700 nm). Three common methods such as multi-linear regression, principal component analysis and partial least square regression were employed in forecast modeling, the good results were obtained, and both Rc2 and Rv2 reached about 0.9. The method has proven effective and feasible for prediction of chlorophyll contents of tomato leaves, which also lays the foundation for the development of testing instruments for the growing of crops.

[Effect of cisplatin on expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 and their correlations in Lewis lung cancer in mice].

BACKGROUND AND OBJECTIVE: Metastasis of lung cancer is the leading cause of disease progression and treatment failure. Matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) are related to the metastasis of lung cancer via regulating the degradation of extracellular matrix. This study was to observe the impacts of cisplatin (DDP) on the expression of MMP-9 and TIMP-1 in Lewis lung cancer, and explore their correlations and roles in metastasis. METHODS: Lewis lung cancer model was established in C57BL/6 mice. DDP group was given intraperitoneal DDP injection, and compared with normal control and tumor-bearing groups. The expression of MMP-9 and TIMP-1 were determined by ELISA in serum and detected by immunohistochemistry in tumor tissues. RESULTS: The inhibition rates of tumor growth and metastasis were 41.2% and 39.0% in DDP group, respectively. The positive rates of MMP-9 and TIMP-1 were 100% in tumor-bearing group, and their serum concentrations were significantly higher in tumor-bearing group than in normal control group (P<0.05). Serum concentrations of MMP-9 and TIMP-1, and positive rate of MMP-9 were all significantly lower in DDP group than in tumor-bearing group (P<0.05). Serum concentration of MMP-9 and positive rates of MMP-9 and TIMP-1 were positively correlated to tumor weight (r=0.665, 0.749 and 0.615, all P<0.05) and lung metastasis (r=0.668, 0.545 and 0.664, all P<0.05). MMP-9 expression was positively correlated to TIMP-1 expression both in serum and tumor (r=0.617 and 0.695, all P<0.05). The ratio of sMMP-9/TIMP-1 became a constant in normal distribution, with a mean of 1.72. CONCLUSIONS: Both MMP-9 and TIMP-1 are highly expressed in Lewis lung cancer, correlated to tumor invasion and metastasis. DDP may suppress tumor metastasis via down-regulating the expression of MMP-9 and TIMP-1 in serum and tumor.