Pan-genome of Citrullus genus highlights the extent of presence/absence variation during domestication and selection.

The rich genetic diversity in Citrullus lanatus and the other six species in the Citrullus genus provides important sources in watermelon breeding. Here, we present the Citrullus genus pan-genome based on the 400 Citrullus genus resequencing data, showing that 477 Mb contigs and 6249 protein-coding genes were absent in the Citrullus lanatus reference genome. In the Citrullus genus pan-genome, there are a total of 8795 (30.5%) genes that exhibit presence/absence variations (PAVs). Presence/absence variation (PAV) analysis showed that a lot of gene PAV were selected during the domestication and improvement, such as 53 favorable genes and 40 unfavorable genes were identified during the C. mucosospermus to C. lanatus landrace domestication. We also identified 661 resistance gene analogs (RGAs) in the Citrullus genus pan-genome, which contains 90 RGAs (89 variable and 1 core gene) located on the pangenome additional contigs. By gene PAV-based GWAS, 8 gene presence/absence variations were found associated with flesh color. Finally, based on the results of gene PAV selection analysis between watermelon populations with different fruit colors, we identified four non-reference candidate genes associated with carotenoid accumulation, which had a significantly higher frequency in the white flesh. These results will provide an important source for watermelon breeding.

A cross-sectional study on the effect of dietary zinc intake on the relationship between serum vitamin D3 and HOMA-IR.

Introduction: Serum vitamin D3 concentration is associated with the risk of insulin resistance. Zinc has also been reported to be associated with a lower risk of insulin resistance. In addition, zinc is an essential cofactor in the activation of vitamin D3. However, the effect of dietary zinc intake on the relationship between vitamin D3 and insulin resistance risk has not been fully studied. Therefore, we designed this cross-sectional study to assess the impact of changes in zinc intake on the relationship between vitamin D3 and insulin resistance risk. Study design and methods: This study analyzed data from the national Health and Nutrition Examination Survey (NHANES) from 2005 to 2018, involving 9,545 participants. Participants were stratified by zinc intake category (low zinc intake <9.58 mg/ day; High zinc intake: ≥9.58 mg/ day). Results: In this cross-sectional study, serum vitamin D3 levels were independently associated with the risk of insulin resistance in both the low and high Zinc intakes (ß: -0.26, 95%Cl: -0.56~0.04 vs. ß: -0.56, 95%Cl: -1.01~-0.11). In addition, this association was influenced by different dietary zinc intakes (interaction P < 0.05). Conclusions: Our results suggest that zinc intake may influence the association between serum vitamin D3 and the risk of insulin resistance. Further randomized controlled trials are needed to provide more evidence of this finding.

The main component of the aphid alarm pheromone (E)-ß-farnesene affects the growth and development of Spodoptera exigua by mediating juvenile hormone-related genes.

The (E)-ß-farnesene (EßF) is one of the most important secondary metabolites in some plants and provides indirect defense against aphids. However, the direct effect of EßF against pests is still unclear. In this study, various concentrations of EßF (0.16, 0.8, and 4 g/kg) were provided in an artificial diet to determine the direct effects of EßF on Spodoptera exigua. The results showed that an artificial diet containing 4 g/kg of EßF reduced the final survival of the S. exigua larvae and per female fecundity of adults significantly when compared with CK and SC controls (p < 0.05), then ultimately it also significantly affected the intrinsic rate of increase (p < 0.05). Furthermore, the results of the EßF bioassay in an artificial diet also indicated that the proliferation of the S. exigua population was inhibited by the ingestion of EßF in a dose-dependent manner. Combined differential RNA-seq data and RT-qPCR analysis, it was found that four key genes involved in juvenile hormone degradation significantly upregulated in S. exigua larvae treated by EßF at a dose of 0.8 and 4 g/kg when compared with two controls (p < 0.05). This indicated that EßF could disturb the normal function of juvenile hormones and reduce the survival rate of S. exigua larvae. Additionally, two key genes that regulate per fecundity of S. exigua females, including SeVg and SeVgR, were significantly downregulated in adult females (p < 0.05) when they were treated with 0.8 and 4 g/kg of EßF at the larval stage, relative to the expression of these genes after treatment with controls. These findings suggested that EßF first disturbed the normal function of juvenile hormone by upregulating key degradation genes, and then inhibited the expression of SeVg/SeVgR genes and proteins, thus reducing the population size of S. exigua by increasing larval mortality and inhibiting per female fecundity.

[Application value of Provider-Initiated HIV Testing and Counseling in dermatology].

OBJECTIVE: To explore the clinical application value of Provider-Initiated HIV Testing and Counseling (PITC) by analyzing the positive rate of HIV tests for people in need of PITC and that of routine HIV tests. METHODS: We retrospectively analyzed the demographic and epidemiologic data about the patients seeking PITC services or undergoing routine HIV tests in Nanjing Drum Tower Hospital between January and December 2013. RESULTS: The positive rate of initial HIV screening was 1.98% in the PITC group and 0.24% in the routine test group, while that of confirmed HIV was 0. 40% in the former and 0.07% in the latter, both with statistically significant differences between the two groups (P < 0.01). The positive rate of HIV was markedly higher in males than in females, particularly in the PITC group. CONCLUSION: PITC has a high clinical value in HIV detection for targeted subjects and therefore deserves general application in dermatology.

[Identification of Puumala like viruses in China].

BACKGROUND: To confirm if Puumala like viruses exist in China. METHODS: RNA was extracted from lungs of bank voles captured in the Northeast China, partial S segments genome of Puumala viruses were amplified and sequenced. RESULTS: 926 bp cDNA of S segments of Puumala like virus was amplified and sequenced. The phylogenetic analysis revealed that the Puumala like viruses found in China were most close to that found in Far East region of Russia. CONCLUSIONS: Puumala like virus does exist in Northeast China, and the nucleotides sequence of the viruses have high homolog to Puumala viruses found in Russia.