A new triterpenoid saponin and a new natural saponin from the roots of Bupleurum scorzonerifolium willd.

Sixteen triterpenoid saponins were isolated from the roots of Bupleurum scorzonerifolium Willd., including a new triterpenoid saponin and new natural saponin that was characterised by NMR for the first time, along with 14 known triterpenoid saponins. The structures of the compounds were established by 1D and 2D NMR spectroscopy, HR-ESI-MS, and comparison with the literature. The cytotoxic activity of the compounds against 4T1 cells was determined using the CCK8 method. Compounds 9 and 6 showed the strongest cytotoxic activity with IC50 values of 2.75 ± 0.86 and 3.78 ± 0.50 µM, respectively. Compounds 2-5 and 8 showed potent cytotoxic activity. Compounds 14 and 16 showed moderate cytotoxicity.

Cytotoxicity phenylpropanoid amides from the seed of Cannabis sativa L.

Two novel phenylpropanoid amides, namely huomarenamide A (1) and huomarenamide B (2), along with twelve known compounds (3-14), were isolated from the seeds of Cannabis sativa L. The structures with absolute configurations of new compounds were unequivocally determined by spectroscopic analyses and the ECD method. The identification of the known compounds was based on a comparison of their 1D NMR data with literature references. All compounds were assessed for cytotoxic activity against LN229 cells, revealing that compounds 2, 13, and 14 exhibited significant cytotoxicity with IC50 values ranging from 9.02 to 21.26 µM.

Seven new triterpenoids from the roots of Adenophora tetraphylla (Thub.) Fisch.

Seven new triterpenoids, named Adeterpenoids A-G (1-7) and eight known compounds (8-15), were isolated from 70% ethanol extract of the roots of Adenophora tetraphylla (Thub.) Fisch. The compounds from it were separated by column chromatography techniques such as silica gel, ODS, and preparative liquid chromatography. Their structures were clarified based on extensive spectral analysis (1D, 2D-NMR, HR-ESI-MS, IR, UV, and CD) and comparison with the literature. At the same time, all compounds were evaluated for their cytotoxic activity against the LN229 (human glioma cell line). The results showed that compounds 2, 5, 6, 13, and 14 had a significant inhibitory effect on LN229 cells.

Benzoylaconitine: A promising ACE2-targeted agonist for enhancing cardiac function in heart failure.

Benzoylaconitine is a natural product in the treatment of cardiovascular disease. However, its pharmacological effect, direct target protein, and molecular mechanisms for the treatment of heart failure are unclear. In this study, benzoylaconitine inhibited Ang II-induced cell hypertrophy and fibrosis in rat primary cardiomyocytes and rat fibroblasts, while attenuating cardiac function and cardiac remodeling in TAC mice. Using the limited proteolysis-mass spectrometry (LiP-MS) method, the angiotensin-converting enzyme 2 (ACE2) was confirmed as a direct binding target of benzoylaconitine for the treatment of heart failure. In ACE2-knockdown cells and ACE2-/- mice, benzoylaconitine failed to ameliorate cardiomyocyte hypertrophy, fibrosis, and heart failure. Online RNA-sequence analysis indicated p38/ERK-mediated mitochondrial reactive oxygen species (ROS) and nuclear factor kappa B (NF-κB) activation are the possible downstream molecular mechanisms for the effect of BAC-ACE2 interaction. Further studies in ACE2-knockdown cells and ACE2-/- mice suggested that benzoylaconitine targeted ACE2 to suppress p38/ERK-mediated mitochondrial ROS and NF-κB pathway activation. Our findings suggest that benzoylaconitine is a promising ACE2 agonist in regulating mitochondrial ROS release and inflammation activation to improve cardiac function in the treatment of heart failure.

New recessive compound heterozygous variants of RP1L1 in RP1L1 maculopathy.

AIM: To identify a maculopathy patient caused by new recessive compound heterozygous variants in RP1L1. METHODS: Comprehensive retinal morphological and functional examinations were evaluated for the patient with RP1L1 maculopathy. Targeted sequence capture array technique was used to screen potential pathologic variants. Polymerase chain reaction and Sanger sequencing were used to confirm the screening results. RESULTS: Fundus examination showed round macular lesions appeared in both eyes. Optical coherence tomography showed that the inner segment/outer segment continuity was disorganized and disruptive in the left eye, but it was uneven and slightly elevated in the right eye. Fundus autofluorescence showed patchy hyper-autofluorescence in the macula. Visual field examination indicates central defects in both eyes. Electroretinogram (ERG) and multifocal ERG showed no obvious abnormalities. Fundus fluorescein angiography in the macula showed obviously irregular hyper-fluorescence in the right eye and slightly hyper-fluorescence in the left eye. We found that the proband carried a missense variant (c.1972C>T) and a deletion variant (c.4717_4718del) of RP1L1, which were originated from the parents and formed compound heterozygous variants. Both variants are likely pathogenic according to the ACMG criteria. Multimodal imaging, ERG and detailed medical history are important diagnostic tools for differentiating between acquired and inherited retinal disorders. CONCLUSION: A maculopathy case with detailed retinal phenotype and new recessive compound heterozygous variants of RP1L1 is identified in a Chinese family, which expands the understanding of phenotype and genotype in RP1L1 maculopathy.

Loss of HRD functional phenotype impedes immunotherapy and can be reversed by HDAC inhibitor in ovarian cancer.

In recent years, homologous recombination deficiency (HRD) has not achieved the expected substantial promotion of immunotherapeutic efficacy in ovarian cancer. This study aims to explore the role of HRD functional phenotype as a powerful biomarker in identifying HRD patients who may benefit from immunotherapy. HRD functional phenotype, namely HRD-EXCUTE, was defined as the average level of the 15 hub genes upregulated in HRD ovarian cancer. A decision tree was plotted to evaluate the critical role of HRD-EXCUTE in HRD patients. Agents inducing HRD-EXCUTE were identified by CMAP web (Connectivity Map). The mechanisms and immunotherapeutic effect of PARPi and HDACi in promoting HRD-EXCUTE was examined in vitro and in vivo. The decision tree plotted on the basis of HRD and HRD-EXCUTE indicated the HRD patients without the HRD functional phenotype were largely unresponsive to immunotherapy, which was validated by the immunotherapeutic cohorts. Furthermore, loss of HRD-EXCUTE in the HRD patients attenuated immunogenicity and inhibited immune cells in tumor microenvironment. Moreover, Niraparib combined with Entinostat induced HRD-EXCUTE by activating the cGAS-STING pathway and increasing the histone acetylation. The combination therapy could enhance the cytotoxicity of immune cells, and promote pro-immune cells infiltrating into ascites, resulting in inhibited ovarian cancer growth. The HRD functional phenotype HRD-EXCUTE was set up as a potent biomarker to identify whether HRD patients can benefit from immunotherapy. Loss of HRD-EXCUTE in HRD patients were largely insensitive to immunotherapy. The combination of PARPi with HDACi could improve the efficacy of the PARPi-based immunotherapy in ovarian cancer by augmenting the HRD functional phenotype.

SoySNP618K array: A high-resolution single nucleotide polymorphism platform as a valuable genomic resource for soybean genetics and breeding.

Innovations in genomics have enabled the development of low-cost, high-resolution, single nucleotide polymorphism (SNP) genotyping arrays that accelerate breeding progress and support basic research in crop science. Here, we developed and validated the SoySNP618K array (618,888 SNPs) for the important crop soybean. The SNPs were selected from whole-genome resequencing data containing 2,214 diverse soybean accessions; 29.34% of the SNPs mapped to genic regions representing 86.85% of the 56,044 annotated high-confidence genes. Identity-by-state analyses of 318 soybeans revealed 17 redundant accessions, highlighting the potential of the SoySNP618K array in supporting gene bank management. The patterns of population stratification and genomic regions enriched through domestication were highly consistent with previous findings based on resequencing data, suggesting that the ascertainment bias in the SoySNP618K array was largely compensated for. Genome-wide association mapping in combination with reported quantitative trait loci enabled fine-mapping of genes known to influence flowering time, E2 and GmPRR3b, and of a new candidate gene, GmVIP5. Moreover, genomic prediction of flowering and maturity time in 502 recombinant inbred lines was highly accurate (>0.65). Thus, the SoySNP618K array is a valuable genomic tool that can be used to address many questions in applied breeding, germplasm management, and basic crop research.

Association between blood urea nitrogen and incidence of type 2 diabetes mellitus in a Chinese population: a cohort study.

To examine the association between blood urea nitrogen (BUN) and risk of type 2 diabetes (T2DM) among Chinese adults, we performed an ongoing cohort study of 38578 Chinese adults (56.3% males; average age, 41.6 y) who underwent repeated health check-up examinations between 2009 and 2016 and without T2DM at baseline. During follow-up, incident T2DM cases were identified based on self-report, medication use, measurements of fasting plasma glucose, 2 h post oral glucose, or haemoglobinA1c. 2009 (5.2%) cases confirmed with incident T2DM were identified during median follow-up of 3.1 years. With increasing quartiles of BUN levels, the incidences of T2DM gradually increased with 0.69%, 1.11%, 1.53%, and 1.87% for quartile 1 to quartile 4 (p trend <0.001). Compared with quartile 1, the multivariate-adjusted hazard ratios (HRs) and its 95% confidence intervals (95% CIs) for T2DM risk were 1.16 (0.97-1.38) for quartile 2, 1.28 (1.07-1.51) for quartile 3, and 1.28 (1.08-1.52) for quartile 4 (p trend = 0.005). HR for per each standard deviation increase in BUN level was 1.10 (1.04-1.16) (p trend <0.001). This association tended to be more pronounced in those with a lower body mass index at baseline (p-interaction <0.001). Our results suggested that BUN levels were positively associated with incident T2DM risk among Chinese adults. Future prospective investigations in other populations are necessary to confirm our findings.

The association between dietary fatty acid intake and the risk of developing preeclampsia: a matched case-control study.

The association between dietary fat intake during pregnancy and the risk of developing preeclampsia has been examined in many epidemiological studies, but the results remain inconsistent. The aim of this study was to clarify this association in pregnant Chinese women. After conducting 1:1 matching, 440 pairs consisting of pregnant women with preeclampsia and hospital-based, healthy pregnant women matched by gestational week (± 1 week) and age (± 3 years) were recruited. A 79-item semi-quantitative food frequency questionnaire administered during face-to-face interviews was used to estimate the participants' dietary intake of fatty acids. We found that the intakes of arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were inversely associated with the risk of developing preeclampsia. Compared with the lowest quartile intake, the multivariate-adjusted odds ratios (95% confidence interval) of the highest quartile intake were 0.42 (0.26-0.68, p-trend < 0.001) for EPA, 0.52 (0.3-0.83, p-trend = 0.005) for DHA, and 0.41 (0.19-0.88, p-trend = 0.007) for AA. However, we did not observe any significant associations between the intake of total fatty acids, saturated fatty acids, and mono-unsaturated fatty acids and the risk of developing preeclampsia. Our results showed that the dietary intake of long-chain polyunsaturated fatty acids (i.e., EPA, DHA, and AA) may protect pregnant Chinese women against the development of preeclampsia.

Effects of dairy products, calcium and vitamin D on ovarian cancer risk: a meta-analysis of twenty-nine epidemiological studies.

Findings for the roles of dairy products, Ca and vitamin D on ovarian cancer risk remain controversial. We aimed to assess these associations by using an updated meta-analysis. Five electronic databases (e.g. PubMed and Embase) were searched from inception to 24 December 2019. Pooled relative risks (RR) with 95 % CI were calculated. A total of twenty-nine case-control or cohort studies were included. For comparisons of the highest v. lowest intakes, higher whole milk intake was associated with increased ovarian cancer risk (RR 1·35; 95 % CI 1·15, 1·59), whereas decreased risks were observed for higher intakes of low-fat milk (RR 0·84; 95 % CI 0·73, 0·96), dietary Ca (RR 0·71; 95 % CI 0·60, 0·84) and dietary vitamin D (RR 0·80; 95 % CI 0·67, 0·95). Additionally, for every 100 g/d increment, increased ovarian cancer risks were found for total dairy products (RR 1·03; 95 % CI 1·01, 1·04) and for whole milk (RR 1·07; 95 % CI 1·03, 1·11); however, decreased risks were found for 100 g/d increased intakes of low-fat milk (RR 0·95; 95 % CI 0·91, 0·99), cheese (RR 0·87; 95 % CI 0·76, 0·98), dietary Ca (RR 0·96; 95 % CI 0·95, 0·98), total Ca (RR 0·98; 95 % CI 0·97, 0·99), dietary vitamin D (RR 0·92; 95 % CI 0·87, 0·97) and increased levels of circulating vitamin D (RR 0·84; 95 % CI 0·72, 0·97). These results show that whole milk intake might contribute to a higher ovarian cancer risk, whereas low-fat milk, dietary Ca and dietary vitamin D might reduce the risk.

Analysis of Soybean Somatic Embryogenesis Using Chromosome Segment Substitution Lines and Transcriptome Sequencing.

Soybean is an important cash crop that is widely used as a source of vegetable protein and edible oil. The regeneration ability of soybean directly affects the application of biotechnology. In this study, we used the exogenous hormone 2,4-D to treat immature embryos. Different levels of somatic incidence were selected from the chromosome segment substitution lines (CSSLs) constructed by SN14 and ZYD00006. Transcriptome sequencing of extreme materials was performed, and 2666 differentially expressed genes were obtained. At the same time, a difference table was generated by combining the data on CSSL rearrangement. In the extreme materials, a total of 93 differentially expressed genes were predicted and were then analyzed by cluster analysis and Gene Ontology (GO) annotation. After screening and annotating the target genes, three differentially expressed genes with hormone pathways were identified. The expression patterns of the target genes were verified by real-time quantitative PCR (qRT-PCR). Haplotype polymorphism detection and linkage disequilibrium analysis were performed on the candidate gene Glyma.09g248200. This study provided more information on the regulation network of soybean somatic embryogenesis and regeneration processes, and further identified important genes in the soybean regeneration process and provided a theoretical basis for accelerating the application of biotechnology to soybean for improving its breeding efficiency.

Admission serum sodium and potassium levels predict survival among critically ill patients with acute kidney injury: a cohort study.

BACKGROUND: Patients suffering from acute kidney injury (AKI) were associated with impaired sodium and potassium homeostasis. We aimed to investigate how admission serum sodium and potassium independently and jointly modified adverse clinical outcomes among AKI patients. METHODS: Patient data were extracted from the Multiparameter Intelligent Monitoring in Intensive Care Database III. Participants were categorized into three groups according to admission serum sodium and potassium, and the cut-off values were determined using smooth curve fitting. The primary outcome was 90-day mortality in the intensive care unit (ICU). Cox proportional hazards models were used to evaluate the prognostic effects of admission serum sodium and potassium levels. RESULTS: We included 13,621 ICU patients with AKI (mean age: 65.3 years; males: 55.4%). The middle category of admission serum sodium and potassium levels were 136.0-144.9 mmol/L and 3.7-4.7 mmol/L through fitting smooth curve. In multivariable Cox models, compared with the middle category, patients with hyponatremia or hypernatremia were associated with excess mortality and the HRs and its 95%CIs were 1.38 (1.27, 1.50) and 1.56 (1.36, 1.79), and patients with either hypokalemia or hyperkalemia were associated with excess mortality and the hazard ratios (HRs) and its 95% confidential intervals (95% CIs) were 1.12 (1.02, 1.24) and 1.25 (1.14, 1.36), respectively. Significant interactions were observed between admission serum sodium and potassium levels (P interaction = 0.001), with a higher serum potassium level associated with increased risk of 90-day mortality among patients with hyponatremia, whereas the effects of higher sodium level on prognostic effects of potassium were subtle. CONCLUSIONS: Admission serum sodium and potassium were associated with survival in a U-shaped pattern among patients with AKI, and hyperkalemia predict a worse clinical outcome among patients with hyponatremia.

Analysis of miRNAs Targeted Storage Regulatory Genes during Soybean Seed Development Based on Transcriptome Sequencing.

Soybeans are an important cash crop and are widely used as a source of vegetable protein and edible oil. MicroRNAs (miRNA) are endogenous small RNA that play an important regulatory role in the evolutionarily conserved system of gene expression. In this study, we selected four lines with extreme phenotypes, as well as high or low protein and oil content, from the chromosome segment substitution line (CSSL) constructed from suinong (SN14) and ZYD00006, and planted and sampled at three stages of grain development for small RNA sequencing and expression analysis. The sequencing results revealed the expression pattern of miRNA in the materials, and predicted miRNA-targeted regulatory genes, including 1967 pairs of corresponding relationships between known-miRNA and their target genes, as well as 597 pairs of corresponding relationships between novel-miRNA and their target genes. After screening and annotating genes that were targeted for regulation, five specific genes were identified to be differentially expressed during seed development and subsequently analyzed for their regulatory relationship with miRNAs. The expression pattern of the targeted gene was verified by Real-time Quantitative PCR (RT-qPCR). Our research provides more information about the miRNA regulatory network in soybeans and further identifies useful genes that regulate storage during soy grain development, providing a theoretical basis for the regulation of soybean quality traits.

Cationic liposomes induce cytotoxicity in HepG2 via regulation of lipid metabolism based on whole-transcriptome sequencing analysis.

BACKGROUD: Cationic liposomes (CLs) can be used as non-viral vectors in gene transfer and drug delivery. However, the underlying molecular mechanism of its cytotoxicity has not been well elucidated yet. METHODS: We herein report a systems biology approach based on whole-transcriptome sequencing coupled with computational method to identify the predominant genes and pathways involved in the cytotoxicity of CLs in HepG2 cell line. RESULTS: Firstly, we validated the concentration-dependent cytotoxicity of CLs with an IC50 of 120 µg/ml in HepG2 exposed for 24 h. Subsequently, we used whole-transcriptome sequencing to identify 220 (77 up- and 143 down-regulated) differentially expressed genes (DEGs). Gene ontology (GO) and pathway analysis showed that these DEGs were mainly related to cholesterol, steroid, lipid biosynthetic and metabolic processes. Additionally, "key regulatory" genes were identified using gene act, pathway act and co-expression network analysis, and expression levels of 11 interested altered genes were confirmed by quantitative real time PCR. Interestingly, no cell cycle arrest was observed through flow cytometry. CONCLUSIONS: These data are expected to provide deep insights into the molecular mechanism of CLs cytotoxicity.

A Comparison between Three-Dimensional Visualization Guided Hepatectomy and Ultrasonography Guided Radiofrequency Ablation in the Treatment of Small Hepatocellular Carcinoma within the Milan Criteria.

Background. Treatment selection for small hepatocellular carcinoma (sHCC) is controversial. We aimed to compare the outcomes of medical imaging three-dimensional visualization system (MI-3DVS) guided surgical resection (SR) and ultrasonography guided radiofrequency ablation (RFA) for sHCC. Methods. In total, 194 patients who underwent SR or RFA in our hospital between January 2006 and May 2010 were retrospectively enrolled. Overall survival (OS), recurrence-free survival (RFS), and postoperative complications were compared. Cox regression was used to estimate the benefits of MI-3DVS-guided SR on OS and RFS. Results. Ninety-two patients underwent SR and 102 underwent RFA. The SR group experienced more complications (41.3% versus 19.6%) and longer hospital stay (18.04 ± 7.11 versus 13.06 ± 5.59) (both p < 0.05). The 1-, 2-, 3-, 4-, and 5-year OS was 96.7%, 95.7%, 93.5%, 83.5%, and 61.1% in the SR group and 95.0%, 88.1%, 72.7%, 56.9%, and 39.5% in the RFA group. Corresponding RFS was 95.7%, 94.6%, 84.7%, 59.8%, and 40.2% in SR group and 91.2%, 80.3%, 60.5%, 32.3%, and 22.3% in RFA group. The 5-year OS and RFS were higher in SR group (both p < 0.001). Interestingly, there was no significance in OS and RFS among subgroups aged >60 years. Independent predictors of OS and RFS, respectively, were intervention (HR, 2.769 and 1.933), tumor number (HR, 5.128 and 3.903), and serum alpha-fetoprotein (AFP) (HR, 1.871 and 1.474) (all p < 0.05). Conclusions. MI-3DVS based hepatectomy should be considered primary treatment while RFA can be treated as alternative therapy for older patients. Intervention, tumor number, and AFP are independent predictors for both survival and recurrence.

[Construction and evaluation of the epidemiological injury criteria based on the combination of 'Hurt' and 'Harm'].

OBJECTIVE: To construct and evaluate the criteria of injury based on the theoretical model that 'Injury' is the combination of 'Hurt' and 'Harm', in order to provide theoretical basis for scientific and rational research on injury in future epidemiological survey. METHODS: The criteria of epidemiological injury was consected by analyzing documents and consulting experts, then Delphi method was used to evaluate its rationality. RESULTS: The epidemiological definition for 'Injury'is the combination of 'Hurt' and 'Harm'. 'Hurt' means the wound in clinical medicine, while 'Harm' means the damage from the views of public health. The active coefficients of two rounds Delphi Method were both 100%. The authority coefficients of two rounds were 0.88 and 0.87, respectively. The coordination coefficients were 0.44 and 0.62 (P<0.05), respectively. After two rounds consulting, all scores of rationality for definition of 'Hurt', definition of 'Harm', 'Injury' being the combination of 'hurt' and 'harm', 'Injury' should be graded, Graded based on the 'Injured' time were above 3, and all values of CV for those index were below 0.25 except Graded based on the 'Injured' time. CONCLUSION: The rationality of Definition of 'Hurt', Definition of 'Harm', 'Injury' being the combination of 'hurt' and 'harm', 'Injury' should be graded and Graded based on the 'Injured' time is good. There is still a certain degree of divergence about Graded based on the 'Injured' time.

Body Mass Index and Stump Morphology Predict an Increased Incidence of Pancreatic Fistula After Pancreaticoduodenectomy.

BACKGROUND: A majority of factors associated with the occurrence of clinical relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy (PD) can only be identified intra- or postoperatively. There are no reports for assessing the morphological features of pancreatic stump and analyzing its influence on CR-POPF risk after PD preoperatively. METHOD: A total of 90 patients underwent PD between April 2012 and May 2014 in our hospital were included. Preoperative computed tomographic (CT) images were imported into the Medical Image Three-Dimensional Visualization System (MI-3DVS) for acquiring the morphological features of pancreatic stump. The demographics, laboratory test and morphological features of pancreatic stump were recorded prospectively. The clinical course was evaluated focusing on the occurrence of pancreatic fistula as defined by the International Study Group on Pancreatic Fistula (ISGPF). Logistic regression analysis was used to identify independent predictors of CR-POPF. RESULTS: CR-POPF occurred in 18 patients (14 grade B, 4 grade C). In univariate analysis, male gender (P = 0.026), body mass index (BMI) ≥ 25.3 kg/m(2) (P = 0.002), main pancreas duct diameter (MPDD) < 3.1 mm (P = 0.005), remnant pancreatic parenchymal volume (RPPV) > 27.8 mL (P < 0.001), and area of cut surface (AOCS) > 222.3 mm(2) (P < 0.001) were associated with an increased risk of CR-POPF. In multivariate analysis, BMI ≥ 25.3 kg/m(2) (OR 12.238, 95 % CI 1.822-82.215, P = 0.010) and RPPV > 27.8 mL (OR 12.907, 95 % CI 1.602-104.004, P = 0.016) were the only independent risk factors associated with CR-POPF. A cut-off value of 27.8 mL for RPPV established based on the receiver operating characteristic (ROC) curve, which was the strongest single predictive factor for CR-POPF, with a sensitivity and specificity of 77.8 and 86.1 %, respectively. The area under the ROC curve of RPPV was 0.770 (95 % CI 0.629-0.911, P < 0.001). CONCLUSIONS: Our study demonstrated that CR-POPF is correlated with BMI and RRPV. MI-3DVS provides us a novel and convenient method for measuring the RPPV. Preoperative acquisition of RPPV and BMI may help the surgeons in fitting postoperative management to patient's individual risk after PD.

The evolution of soybean mosaic virus: An updated analysis by obtaining 18 new genomic sequences of Chinese strains/isolates.

Soybean mosaic virus (SMV) is widely recognized as a highly damaging pathogen of soybean, and various strains/isolates have been reported to date. However, the pathogenic differences and phylogenetic relationships of these SMV strains/isolates have not been extensively studied. In the present work, by first obtaining 18 new genomic sequences of Chinese SMV strains/isolates and further compiling these with available data, we have explored the evolution of SMV from multiple aspects. First, as in other potyviruses, recombination has occurred frequently during SMV evolution, and a total of 32 independent events were detected. Second, using a maximum-likelihood method and removing recombinant fragments, a phylogeny covering 83 SMV sequences sampled from all over the world was reconstructed and the results showed four separate SMV clades, with clade I and II recovered for the first time. Third, the population structure analysis of SMV revealed significant genetic differentiations between China and two other countries (Korea and U.S.A.). Fourth, certain SMV-encoded genes, such as P1, HC-Pro and P3, exhibited higher non-synonymous substitution rate (dN) than synonymous substitution rate (dS), indicating that positive selection has influenced these genes. Finally, four Chinese SMV strains/isolates were selected for inoculation of both USA and Chinese differential soybean cultivars, and their pathogenic phenotypes were significantly different from that of the American strains. Overall, these findings have further broadened our understanding on SMV evolution, which would assist researchers to better deal with this harmful virus.

Multi-environment mapping and meta-analysis of 100-seed weight in soybean.

100-Seed weight (100-SW) of soybean is an important but complicated quantitative trait to yield. This study was focus on the quantitative trait loci (QTLs) of soybean 100-SW from 2006 to 2010, using recombination inbred lines population that was derived from a cross between Charleston and Dongnong 594. A total of 23 QTLs for 100-SW were detected in the linkage group C2, D1a, F, G and O. Nine QTLs were identified by composite interval mapping including one QTL with the minimum confidence interval (CI) of 1.3 cM, while 14 QTLs by multiple interval mapping. Furthermore, 94 reported QTLs of 100-SW were integrated with our QTL mapping results using BioMercator. As a result, 15 consensus QTLs and their corresponding markers were identified. The minimum CI was reduced to 1.52 cM by the combination of meta-analysis. These findings may merit fine-mapping of these QTL in soybean.

Dissection of genetic overlap of drought and low-temperature tolerance QTLs at the germination stage using backcross introgression lines in soybean.

Northeast of China is the main soybean production area, drought and low-temperature tolerance are both main factors involved in reducing soybean yield and limiting planting regions, the most effective way to solve this problem is to breed cultivars with drought and low-temperature tolerance. A set of the BC(2)F(3) lines was constructed with Hongfeng 11 as recurrent parent and Harosoy as donor parent, and screened in drought and low-temperature condition at the germination stage. Related QTLs were obtained by Chi-test and ANOVA analysis with genotypic and phenotypic data. Eighteen QTLs of drought tolerance and 23 QTLs of low-temperature tolerance were detected. Among them, 12 QTLs were correlated with both drought and low-temperature tolerance, which showed a partial genetic overlap between drought and low-temperature tolerance at the germination stage in soybean. Among the 12 genetic overlap QTLs, Satt253, Satt513, Satt693, Satt240, Satt323, and Satt255 were detected by at least one method for both drought and low-temperature tolerance. Satt557, Satt452, Sat_331, Satt338, Satt271, and Satt588 were detected by only one analysis method. The QTLs detected above were significant loci for drought or low-temperature tolerance in soybean. This will play an important role in MAS for development of both drought and low-temperature tolerance variety.