Soluble uric acid inhibits ß2 integrin-mediated neutrophil recruitment in innate immunity.

Neutrophils are key players during host defense and sterile inflammation. Neutrophil dysfunction is a characteristic feature of the acquired immunodeficiency during kidney disease. We speculated that the impaired renal clearance of the intrinsic purine metabolite soluble uric acid (sUA) may account for neutrophil dysfunction. Indeed, hyperuricemia (HU, serum UA of 9-12 mg/dL) related or unrelated to kidney dysfunction significantly diminished neutrophil adhesion and extravasation in mice with crystal- and coronavirus-related sterile inflammation using intravital microscopy and an air pouch model. This impaired neutrophil recruitment was partially reversible by depleting UA with rasburicase. We validated these findings in vitro using either neutrophils or serum from patients with kidney dysfunction-related HU with or without UA depletion, which partially normalized the defective migration of neutrophils. Mechanistically, sUA impaired ß2 integrin activity and internalization/recycling by regulating intracellular pH and cytoskeletal dynamics, physiological processes that are known to alter the migratory and phagocytic capability of neutrophils. This effect was fully reversible by blocking intracellular uptake of sUA via urate transporters. In contrast, sUA had no effect on neutrophil extracellular trap formation in neutrophils from healthy subjects or patients with kidney dysfunction. Our results identify an unexpected immunoregulatory role of the intrinsic purine metabolite sUA, which contrasts the well-known immunostimulatory effects of crystalline UA. Specifically targeting UA may help to overcome certain forms of immunodeficiency, for example in kidney dysfunction, but may enhance sterile forms of inflammation.

Ribosome footprint profiling enables elucidating the systemic regulation of fatty acid accumulation in Acer truncatum.

BACKGROUND: The accumulation of fatty acids in plants covers a wide range of functions in plant physiology and thereby affects adaptations and characteristics of species. As the famous woody oilseed crop, Acer truncatum accumulates unsaturated fatty acids and could serve as the model to understand the regulation and trait formation in oil-accumulation crops. Here, we performed Ribosome footprint profiling combing with a multi-omics strategy towards vital time points during seed development, and finally constructed systematic profiling from transcription to proteomes. Additionally, we characterized the small open reading frames (ORFs) and revealed that the translational efficiencies of focused genes were highly influenced by their sequence features. RESULTS: The comprehensive multi-omics analysis of lipid metabolism was conducted in A. truncatum. We applied the Ribo-seq and RNA-seq techniques, and the analyses of transcriptional and translational profiles of seeds collected at 85 and 115 DAF were compared. Key members of biosynthesis-related structural genes (LACS, FAD2, FAD3, and KCS) were characterized fully. More meaningfully, the regulators (MYB, ABI, bZIP, and Dof) were identified and revealed to affect lipid biosynthesis via post-translational regulations. The translational features results showed that translation efficiency tended to be lower for the genes with a translated uORF than for the genes with a non-translated uORF. They provide new insights into the global mechanisms underlying the developmental regulation of lipid metabolism. CONCLUSIONS: We performed Ribosome footprint profiling combing with a multi-omics strategy in A. truncatum seed development, which provides an example of the use of Ribosome footprint profiling in deciphering the complex regulation network and will be useful for elucidating the metabolism of A. truncatum seed oil and the regulatory mechanisms.

Utilization of laparoscopic and open inguinal hernia repair at a large hernia center in China: a single-center observational study.

BACKGROUND: The utilization of laparoscopic and open inguinal hernia repair in China remains unclear. We aim to investigate the rates of laparoscopic and open inguinal hernia repairs and its associated factors at a large hernia center. METHODS: Data were obtained from the front sheet of medical records of Beijing Chaoyang hospital. Adult inguinal hernia inpatients who underwent hernia repairs between 2013 and 2020 were included. We calculated the overall rates of laparoscopic and open inguinal hernia repairs and compared the rate of laparoscopic repairs between different sex, age groups, types, and sides of inguinal hernias. Multivariable logistic regression was used to examine factors associated with the rate of laparoscopic repairs. RESULTS: 14,481 inpatients with inguinal hernia were included. 91.78% were male, 75.43% were more than 50 years, 75.20% were unilateral inguinal hernia, and 64.57% were indirect inguinal hernia. Overall, 49.47% underwent laparoscopic repairs and 50.53% underwent open repairs. Women had lower rate of laparoscopic repair than men, especially in those with unilateral hernias. Bilateral and direct inguinal hernia had higher rates of laparoscopic repair than unilateral and indirect inguinal hernia. Multivariable logistic regression showed that inpatients who were women, > 70 years, pantaloon inguinal hernia, with obstruction, and more comorbidities were less likely to have laparoscopic repairs. CONCLUSION: Around 50% of inguinal hernia patients at a large hernia center underwent laparoscopic repairs, which was more commonly performed in male, young, bilateral inguinal hernia, and inpatients without comorbidities. More efforts were needed to increase the safe and effective laparoscopic utilization among female patients with inguinal hernias.

Transcriptome profiling provides insights into leaf color changes in two Acer palmatum genotypes.

BACKGROUND: Ornamental trees with seasonally-dependent leaf color, such as Acer palmatum, have gained worldwide popularity. Leaf color is a main determinant of the ornamental and economic value of A. palmatum. However, the molecular mechanisms responsible for leaf color changes remain unclear. RESULTS: We chose A. palmatum cultivars with yellow ('Jinling Huangfeng') and red ('Jinling Danfeng') leaves as the ideal material for studying the complex metabolic networks responsible for variations in leaf coloration. The 24 libraries obtained from four different time points in the growth of 'Jinling Huangfeng' and 'Jinling Danfeng' was subjected to Illumina high-throughput sequencing. We observed that the difference in cyanidin and delphinidin content is the primary reason behind the varying coloration of the leaves. Transcriptomic analyses revealed 225,684 unigenes, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of differentially expressed genes (DEGs) confirmed that they were involved in 'anthocyanin biosynthesis.' Eighteen structural genes involved in anthocyanin biosynthesis were thought to be related to anthocyanin accumulation, whereas 46 MYBs, 33 basic helix-loop-helixs (bHLHs), and 29 WD40s were presumed to be involved in regulating anthocyanin biosynthesis. Based on weighted gene co-expression network analysis (WGCNA), three candidate genes (ApRHOMBOID, ApMAPK, and ApUNE10) were screened in the significant association module with a correlation coefficient (r2) of 0.86. CONCLUSION: In this study, the leaf color changes of two A. palmatum genotypes were analyzed. These findings provide novel insights into variations in leaf coloration and suggest pathways for targeted genetic improvements in A. palmatum.

Assembly and comparative analysis of the first complete mitochondrial genome of Acer truncatum Bunge: a woody oil-tree species producing nervonic acid.

BACKGROUND: Acer truncatum (purpleblow maple) is a woody tree species that produces seeds with high levels of valuable fatty acids (especially nervonic acid). The species is admired as a landscape plant with high developmental prospects and scientific research value. The A. truncatum chloroplast genome has recently been reported; however, the mitochondrial genome (mitogenome) is still unexplored. RESULTS: We characterized the A. truncatum mitogenome, which was assembled using reads from PacBio and Illumina sequencing platforms, performed a comparative analysis against different species of Acer. The circular mitogenome of A. truncatum has a length of 791,052 bp, with a base composition of 27.11% A, 27.21% T, 22.79% G, and 22.89% C. The A. truncatum mitogenome contains 62 genes, including 35 protein-coding genes, 23 tRNA genes and 4 rRNA genes. We also examined codon usage, sequence repeats, RNA editing and selective pressure in the A. truncatum mitogenome. To determine the evolutionary and taxonomic status of A. truncatum, we conducted a phylogenetic analysis based on the mitogenomes of A. truncatum and 25 other taxa. In addition, the gene migration from chloroplast and nuclear genomes to the mitogenome were analyzed. Finally, we developed a novel NAD1 intron indel marker for distinguishing several Acer species. CONCLUSIONS: In this study, we assembled and annotated the mitogenome of A. truncatum, a woody oil-tree species producing nervonic acid. The results of our analyses provide comprehensive information on the A. truncatum mitogenome, which would facilitate evolutionary research and molecular barcoding in Acer.

Fertility intentions to have a second or third child under China's three-child policy: a national cross-sectional study.

STUDY QUESTION: What proportion of people want to have a second or third child after the enactment of the three-child policy in China? SUMMARY ANSWER: Under the three-child policy, fertility intention to have a second child was ∼60% (56% of women vs 65% of men), and fertility intention to have a third child was 13% (10% of women vs 17% of men) among the Chinese population. WHAT IS KNOWN ALREADY: The Chinese government announced the three-child policy on 31 May 2021, allowing all couples to have up to three children. At present, there is a lack of national surveys on the fertility intentions of women and men to have a second or third child under the three-child policy in China. STUDY DESIGN, SIZE, DURATION: In June 2021, a national cross-sectional survey including 9243 respondents aged 18-49 years was conducted online from 31 provinces in China's mainland using a random sampling method. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data on the intention to have a second or third child were collected by anonymous questionnaire. Descriptive statistics were performed to assess fertility intentions. Multivariate and multinomial logistic regression analyses were used to assess the association between fertility intentions and the investigated factors. MAIN RESULTS AND THE ROLE OF CHANCE: Approximately 60% (5493/9243) of the investigated people (55.6% women vs 64.7% men) intended to have a second child, and 13.0% (1203/9243) of them (10.0% women vs 17.1% men) intended to have a third child under China's three-child policy. For non-child respondents, 46.8% of women and 60.4% of men intended to have a second child. For one-child respondents, 47.8% of women and 53.8% of men intended to have a second child. For two-child respondents, 14.4% of women and 25.9% of men intended to have a third child. The mean desired family size was 1.58 children per woman, which was lower than the 1.76 children per man. Notably, the age-specified fertility intentions of men were always higher than those of women. Women with a college or higher degree (adjusted odds ratio [aOR] 0.60, 95% CI 0.42-0.88) and a high-middle (aOR 0.71, 95% CI 0.53-0.95) or high (aOR 0.64, 95% CI 0.48-0.85) household income, as well as men living in urban areas (aOR 0.71, 95% CI 0.58-0.87) and having a high-middle household income (aOR 0.68, 95% CI 0.52-0.90), were associated with a lower intention to have a third child (all P < 0.05). In contrast, men of public service personnel had a higher intention to have a third child than factory workers (aOR 1.44, 95% CI 1.02-2.04, P < 0.05). Meanwhile, approximately one out of five two-child respondents intended to have a third child, while one out of four two-girl respondents (aOR 2.09, 95% CI 1.44-3.04) were willing to have a third child with a strong preference for boys (12.7% for boys vs 2.7% for girls). Economic and childrearing barriers were the leading barriers to having one more child. LIMITATIONS, REASONS FOR CAUTION: The online survey might limit the representativeness of the present study's sample. A large sample size was enrolled and a random sampling method was used to increase the sample diversity and representativeness. WIDER IMPLICATIONS OF THE FINDINGS: This study will assist in estimating the impact on population demographic of the three-child policy in China. Multiple efforts are needed to create a fertility-friendly environment for couples, thereby increasing fertility intentions to have one more child and increasing fertility rates. STUDY FUNDING/COMPETING INTEREST(S): No funding. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Soluble Uric Acid Is an Intrinsic Negative Regulator of Monocyte Activation in Monosodium Urate Crystal-Induced Tissue Inflammation.

Although monosodium urate (MSU) crystals are known to trigger inflammation, published data on soluble uric acid (sUA) in this context are discrepant. We hypothesized that diverse sUA preparation methods account for this discrepancy and that an animal model with clinically relevant levels of asymptomatic hyperuricemia and gouty arthritis can ultimately clarify this issue. To test this, we cultured human monocytes with different sUA preparation solutions and found that solubilizing uric acid (UA) by prewarming created erroneous results because of UA microcrystal contaminants triggering IL-1ß release. Solubilizing UA with NaOH avoided this artifact, and this microcrystal-free preparation suppressed LPS- or MSU crystal-induced monocyte activation, a process depending on the intracellular uptake of sUA via the urate transporter SLC2A9/GLUT9. CD14+ monocytes isolated from hyperuricemic patients were less responsive to inflammatory stimuli compared with monocytes from healthy individuals. Treatment with plasma from hyperuricemic patients impaired the inflammatory function of CD14+ monocytes, an effect fully reversible by removing sUA from hyperuricemic plasma. Moreover, Alb-creERT2;Glut9 lox/lox mice with hyperuricemia (serum UA of 9-11 mg/dl) showed a suppressed inflammatory response to MSU crystals compared with Glut9 lox/lox controls without hyperuricemia. Taken together, we unravel a technical explanation for discrepancies in the published literature on immune effects of sUA and identify hyperuricemia as an intrinsic suppressor of innate immunity, in which sUA modulates the capacity of monocytes to respond to danger signals. Thus, sUA is not only a substrate for the formation of MSU crystals but also an intrinsic inhibitor of MSU crystal-induced tissue inflammation.

The prevalence of barriers to rearing children aged 0-3 years following China's new three-child policy: a national cross-sectional study.

BACKGROUND: To further optimize birth policy, China implemented a new three-child policy to allow per couple to have up to three children on May 31, 2021. METHODS: A national cross-sectional survey was conducted among 18 to 49-year-old Chinese parents who had at least one child in June 2021. We calculated the prevalence of self-reported childrearing barriers and used univariate logistic regression and multivariate logistic regression to analyze associated factors. RESULTS: 94.7% of the respondents self-reported barriers to rearing children aged 0-3 years, and the biggest barrier included high time cost (39.3%), high parenting cost (36.5%) and high education cost (13.5%). Women (aOR 1.49, 95%CI 1.13,1.96) and people with college degree or above (aOR 3.46, 95%CI 2.08, 5.75) were associated with higher prevalence of childrearing barriers, and people who intended to have a second child (aOR 0.58, 95%CI 0.40, 0.83) and people who intended to have a third child (aOR 0.51,95%CI 0.37, 0.71) were less likely to report childrearing barriers. The biggest barrier was more likely to be high time cost for parents one of whom is only child (aOR1.21, 95%CI 1.03, 1.42) and physical factors for parents both of whom are only child (aOR 1.56,95%CI 1.08, 2.26). CONCLUSIONS: The prevalence of barriers to rearing children aged 0-3 years was high among Chinese people of childbearing age who had children. Full consideration should be given to the barriers of people with different sociodemographic characteristics and people with fertility intention, thus making targeted childrearing policies and supporting measures to reduce the burden on people of childbearing age, encourage suitable couples to have a second or third child and then cope with China's aging population.

The Acer truncatum genome provides insights into nervonic acid biosynthesis.

Acer truncatum (purpleblow maple) is a woody tree species that produces seeds with high levels of valuable fatty acids (especially nervonic acid). However, the lack of a complete genome sequence has limited both basic and applied research on A. truncatum. We describe a high-quality draft genome assembly comprising 633.28 Mb (contig N50 = 773.17 kb; scaffold N50 = 46.36 Mb) with at least 28 438 predicted genes. The genome underwent an ancient triplication, similar to the core eudicots, but there have been no recent whole-genome duplication events. Acer yangbiense and A. truncatum are estimated to have diverged about 9.4 million years ago. A combined genomic, transcriptomic, metabonomic, and cell ultrastructural analysis provided new insights into the biosynthesis of very long-chain monounsaturated fatty acids. In addition, three KCS genes were found that may contribute to regulating nervonic acid biosynthesis. The KCS paralogous gene family expanded to 28 members, with 10 genes clustered together and distributed in the 0.27-Mb region of pseudochromosome 4. Our chromosome-scale genomic characterization may facilitate the discovery of agronomically important genes and stimulate functional genetic research on A. truncatum. Furthermore, the data presented also offer important foundations from which to study the molecular mechanisms influencing the production of nervonic acids.

Systematic analysis of MYB gene family in Acer rubrum and functional characterization of ArMYB89 in regulating anthocyanin biosynthesis.

The v-myb avian myeloblastosis viral oncogene homolog (MYB) family of transcription factors is extensively distributed across the plant kingdom. However, the functional significance of red maple (Acer rubrum) MYB transcription factors remains unclear. Our research identified 393 MYB transcription factors in the Acer rubrum genome, and these ArMYB members were unevenly distributed across 34 chromosomes. Among them, R2R3 was the primary MYB sub-class, which was further divided into 21 sub-groups with their Arabidopsis homologs. The evolution of the ArMYB family was also investigated, with the results revealing several R2R3-MYB sub-groups with expanded membership in woody species. Here, we report on the isolation and characterization of ArMYB89 in red maple. Quantitative real-time PCR analysis revealed that ArMYB89 expression was significantly up-regulated in red leaves in contrast to green leaves. Sub-cellular localization experiments indicated that ArMYB89 was localized in the nucleus. Further experiments revealed that ArMYB89 could interact with ArSGT1 in vitro and in vivo. Overexpression of ArMYB89 in tobacco enhances the anthocyanin content of transgenic plants. In conclusion, our results contribute to the elucidation of a theoretical basis for the ArMYB gene family, and provide a foundation for further characterization of the biological roles of MYB genes in the regulation of Acer rubrum leaf color.

The association between periconceptional folic acid supplementation and the risk of preterm birth: a population-based retrospective cohort study of 200,000 women in China.

PURPOSE: The aim of this study was to examine the association between periconceptional folic acid (FA) supplementation and risk of preterm birth. METHODS: We conducted a retrospective cohort study in women aged 18-49 who participated in the NFPHEP from 2010 to 2018, and had a singleton livebirth in 129 counties in southwest China. Participants were divided into four groups according to the time period starting FA use: no use, after the last menstrual period, at least 1-2 months before the last menstrual period, at least 3 months before the last menstrual period. The outcomes were preterm birth (gestation < 37 weeks) and early preterm birth (gestation < 34 weeks). RESULTS: 201,477 women were included and 191,809 (95.2%) had taken FA during periconception. Compared with women who did not take FA, women who started taking FA 1-2 months before their last menstrual period had a 15% lower risk of preterm birth (aOR = 0.85, 95% CI 0.79-0.92), and women who started taking FA at least 3 months before their last menstrual period had a 20% lower risk of preterm birth (aOR = 0.80, 95% CI 0.75-0.87), but women who started taking FA after their last menstrual period did not appear to reduce the risk of preterm birth. CONCLUSIONS: In this study of 200,000 Chinese women, periconceptional supplementation with FA was associated with a lower risk of preterm birth. Women who started taking FA at least 3 months before their last menstrual period were more likely to reduce the risk of preterm birth.

Only Hyperuricemia with Crystalluria, but not Asymptomatic Hyperuricemia, Drives Progression of Chronic Kidney Disease.

BACKGROUND: The roles of asymptomatic hyperuricemia or uric acid (UA) crystals in CKD progression are unknown. Hypotheses to explain links between UA deposition and progression of CKD include that (1) asymptomatic hyperuricemia does not promote CKD progression unless UA crystallizes in the kidney; (2) UA crystal granulomas may form due to pre-existing CKD; and (3) proinflammatory granuloma-related M1-like macrophages may drive UA crystal-induced CKD progression. METHODS: MALDI-FTICR mass spectrometry, immunohistochemistry, 3D confocal microscopy, and flow cytometry were used to characterize a novel mouse model of hyperuricemia and chronic UA crystal nephropathy with granulomatous nephritis. Interventional studies probed the role of crystal-induced inflammation and macrophages in the pathology of progressive CKD. RESULTS: Asymptomatic hyperuricemia alone did not cause CKD or drive the progression of aristolochic acid I-induced CKD. Only hyperuricemia with UA crystalluria due to urinary acidification caused tubular obstruction, inflammation, and interstitial fibrosis. UA crystal granulomas surrounded by proinflammatory M1-like macrophages developed late in this process of chronic UA crystal nephropathy and contributed to the progression of pre-existing CKD. Suppressing M1-like macrophages with adenosine attenuated granulomatous nephritis and the progressive decline in GFR. In contrast, inhibiting the JAK/STAT inflammatory pathway with tofacitinib was not renoprotective. CONCLUSIONS: Asymptomatic hyperuricemia does not affect CKD progression unless UA crystallizes in the kidney. UA crystal granulomas develop late in chronic UA crystal nephropathy and contribute to CKD progression because UA crystals trigger M1-like macrophage-related interstitial inflammation and fibrosis. Targeting proinflammatory macrophages, but not JAK/STAT signaling, can attenuate granulomatous interstitial nephritis.

Prevalence of anemia and sociodemographic characteristics among pregnant and non-pregnant women in southwest China: a longitudinal observational study.

BACKGROUND: Globally, the prevalence of anemia among women of reproductive age is about 29.4%, and anemia impacts about 40% of pregnant women and more than 20% of non-pregnant women. We conducted a longitudinal observational study of anemia in pregnant and non-pregnant women, and analyzed the association between the prevalence of anemia and sociodemographic characteristics of women in southwest China. METHODS: This study was a longitudinal observational study which involved 640,672 women aged 18-49 years from 129 counties in southwest China. Data were from databases of National Free Preconception Health Examination Project (NFPHEP) and electronic medical records of local hospitals. We adjusted the diagnostic thresholds of anemia for altitude. The prevalence of anemia was expressed in percentages and 95% confidence intervals (95% CI). The association between the prevalence of anemia and sociodemographic characteristics of pregnant and non-pregnant women were analyzed using univariate and multivariate logistic regression method, expressed in crude odds ratio (cOR), adjusted odds ratio (aOR) and 95%CI. RESULTS: Of the 640,672 participants, 121,254 women suffered from anemia, with the prevalence of 18.9% (95%CI: 18.8-19.0%). From 2014 to 2018, the prevalence of anemia declines from 23.0-16.4%.The prevalence was 21.6% in the first trimester, higher than women in non-pregnancy (17.4%) and women in the third trimester (10.5%). Results from the multivariable logistic regression showed that women aged 18-20 (aOR = 1.28) or over 35 years old (aOR = 1.07), being farmers (aOR = 1.42), being ethnic minorities (aOR: 1.19 ~ 1.73), during the first trimester (aOR = 1.32) were more likely to be anemic. CONCLUSIONS: Although the anemia prevalence of women of reproductive age has been decreasing in recent years, the prevalence of anemia is still high in pregnant and non-pregnant women in southwest China, especially during the first trimester. Women who were older or younger, being farmers, being ethnic minorities were at high risk of anemia. Anemia in women of reproductive age cannot be neglected.

Complete chloroplast genome sequence of a major economic species, Ziziphus jujuba (Rhamnaceae).

Ziziphus jujuba is an important woody plant with high economic and medicinal value. Here, we analyzed and characterized the complete chloroplast (cp) genome of Z. jujuba, the first member of the Rhamnaceae family for which the chloroplast genome sequence has been reported. We also built a web browser for navigating the cp genome of Z. jujuba ( http://bio.njfu.edu.cn/gb2/gbrowse/Ziziphus_jujuba_cp/ ). Sequence analysis showed that this cp genome is 161,466 bp long and has a typical quadripartite structure of large (LSC, 89,120 bp) and small (SSC, 19,348 bp) single-copy regions separated by a pair of inverted repeats (IRs, 26,499 bp). The sequence contained 112 unique genes, including 78 protein-coding genes, 30 transfer RNAs, and four ribosomal RNAs. The genome structure, gene order, GC content, and codon usage are similar to other typical angiosperm cp genomes. A total of 38 tandem repeats, two forward repeats, and three palindromic repeats were detected in the Z. jujuba cp genome. Simple sequence repeat (SSR) analysis revealed that most SSRs were AT-rich. The homopolymer regions in the cp genome of Z. jujuba were verified and manually corrected by Sanger sequencing. One-third of mononucleotide repeats were found to be erroneously sequenced by the 454 pyrosequencing, which resulted in sequences of 1-4 bases shorter than that by the Sanger sequencing. Analyzing the cp genome of Z. jujuba revealed that the IR contraction and expansion events resulted in ycf1 and rps19 pseudogenes. A phylogenetic analysis based on 64 protein-coding genes showed that Z. jujuba was closely related to members of the Elaeagnaceae family, which will be helpful for phylogenetic studies of other Rosales species. The complete cp genome sequence of Z. jujuba will facilitate population, phylogenetic, and cp genetic engineering studies of this economic plant.

IGDD: a database of intronless genes in dicots.

BACKGROUND: Intronless genes are a significant characteristic of prokaryotes. Systematic identification and annotation are primary and crucial steps for determining the functions of intronless genes and understanding their occurrence in eukaryotes. DESCRIPTION: In this paper, we describe the construction of the Intronless Genes Database in Dicots (IGDD; available at http://bio.njfu.edu.cn/igdd/ ), which contains data for five well-annotated plants including Arabidopsis thaliana, Carica papaya, Populus trichocarpa, Salix suchowensis and Vitis vinifera. Using highly visual settings, IGDD displays the structural and functional annotations, the homolog groups, the syntenic relationships, the expression patterns, and the statistical characteristics of intronless genes. In addition, useful tools such as an advanced search and local BLAST are available through a user-friendly and intuitive web interface. CONCLUSION: In conclusion, the IGDD provides a comprehensive and up-to-date platform for researchers to assist the exploration of intronless genes in dicot plants.

Trimeric autotransporter adhesins contribute to Actinobacillus pleuropneumoniae pathogenicity in mice and regulate bacterial gene expression during interactions between bacteria and porcine primary alveolar macrophages.

Actinobacillus pleuropneumoniae is an important pathogen that causes respiratory disease in pigs. Trimeric autotransporter adhesin (TAA) is a recently discovered bacterial virulence factor that mediates bacterial adhesion and colonization. Two TAA coding genes have been found in the genome of A. pleuropneumoniae strain 5b L20, but whether they contribute to bacterial pathogenicity is unclear. In this study, we used homologous recombination to construct a double-gene deletion mutant, ΔTAA, in which both TAA coding genes were deleted and used it in in vivo and in vitro studies to confirm that TAAs participate in bacterial auto-aggregation, biofilm formation, cell adhesion and virulence in mice. A microarray analysis was used to determine whether TAAs can regulate other A. pleuropneumoniae genes during interactions with porcine primary alveolar macrophages. The results showed that deletion of both TAA coding genes up-regulated 36 genes, including ene1514, hofB and tbpB2, and simultaneously down-regulated 36 genes, including lgt, murF and ftsY. These data illustrate that TAAs help to maintain full bacterial virulence both directly, through their bioactivity, and indirectly by regulating the bacterial type II and IV secretion systems and regulating the synthesis or secretion of virulence factors. This study not only enhances our understanding of the role of TAAs but also has significance for those studying A. pleuropneumoniae pathogenesis.

Preparation, Identification and Antioxidant Properties of Black-Bone Silky Fowl (Gallus gallus domesticus Brisson) Iron(II)-Oligopeptide Chelate.

Black-bone silky fowl iron(II)-oligopeptide chelate was synthesized from iron(II) solution and the black-bone silky fowl oligopeptide, which was extracted from the muscle protein of black-bone silky fowl (Gallus gallus domesticus Brisson). Orthogonal array analysis was used to determine the optimal conditions for the iron(II)-oligopeptide chelate preparation. Ultraviolet-visible (UV-Vis) spectroscopy, electron microscopy, and Fourier transform infrared (FTIR) spectroscopy were used to identify the structure of iron(II)-oligopeptide chelate. 2-Diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging assays were performed to compare the antioxidant abilities of the black-bone silky fowl oligopeptide and iron(II)-oligopeptide chelate. The optimal conditions for iron(II)-oligopeptide chelate preparation were 4% of the black-bone silky fowl oligopeptide and a ratio of the black- -bone silky fowl oligopeptide to FeCl2·4H2O of 5:1 at pH=4. Under these conditions, the chelation rate was (84.9±0.2) % (p<0.05), and the chelation yield was (40.3±0.1) % (p<0.05). The structures detected with UV-Vis spectroscopy, electron microscopy and FTIR spectra changed significantly after chelation, suggesting that Fe(II) ions formed coordinate bonds with carboxylate (-RCOOZ) and amino (-NH2) groups in the oligopeptides, confirming that this is a new oligopeptide-iron chelate. The iron(II)-oligopeptide chelate had stronger scavenging activity towards DPPH and superoxide radicals than did the black-bone silky fowl oligopeptide.

Optimised extraction of ß-carotene from Spirulina platensis and hypoglycaemic effect in streptozotocin-induced diabetic mice.

BACKGROUND: Spirulina platensis is rich in ß-carotene, which possesses many important biological activities. This study investigated the ultrasound-assisted extraction and purification of ß-carotene from Spirulina platensis by using response surface methodology (RSM), determined its antioxidant capacity in vitro and explored its hypoglycaemic effect in diabetic mice. RESULTS: The raw ß-carotene extract with a concentration of 1942.14 ± 10.03 µg mL(-1) was obtained at the optimised condition by RSM (0.40 of the solid-liquid ratio, 51% of the extraction power, and 17 min of the extraction time), and the purity of evaporated ß-carotene extract reached 816.32 ± 10.57 mg g(-1) after purified by a NKA-9 resin with a sampling and elution rate of 1 mL min(-1) . The ß-carotene extract scavenged 1,1-diphenyl-2-picrylhydrazyl and hydroxyl free radicals with the highest ratios of 44 ± 0.26% and 35 ± 0.45% respectively, and exhibited strong inhibiting capacity on anti-lipid peroxidation. The blood glucose level of streptozotocin-induced diabetic mice was significantly reduced from 15.81 ± 1.71 mmol L(-1) to 8.10 ± 0.88 mmol L(-1) after 10 d administration of the ß-carotene extract [100 mg kg(-1) body weight (BW)], and the increased food and water intakes in the diabetic mice were also significantly relieved after ß-carotene treatment. CONCLUSION: Our results suggested that extraction of ß-carotene from Spirulina platensis had potential prospects in scaled-up industrialisation and healthcare applications.

Macrophages largely contribute to heterologous anti-Propionibacterium acnes antibody-mediated protection from Actinobacillus pleuropneumoniae infection in mice.

Actinobacillus pleuropneumoniae is the causative agent of acute and chronic pleuropneumonia. Propionibacterium acnes is a facultative anaerobic gram-positive corynebacterium. We have previously found that anti-P. acnes antibodies can prevent A. pleuropneumoniae infections in mice. To investigate the role of macrophages in this process, affinity-purified anti-P. acnes IgG and anti-A. pleuropneumoniae IgG were used in opsonophagocytosis assays. Additionally, the efficacy of passive immunization with P. acnes serum against A. pleuropneumoniae was tested in macrophage-depleted mice. It was found that anti-P. acnes IgG had an effect similar to that of anti-A. pleuropneumoniae IgG (P > 0.05), which significantly promotes phagocytosis of A. pleuropneumoniae by macrophages (P < 0.01). It was also demonstrated that, after passive immunization with anti-P. acnes serum, macrophage-replete mice had the highest survival rate (90%), whereas the survival rate of macrophage-depleted mice was only 40% (P < 0.05). However, macrophage-depleted mice that had been passively immunized with naïve serum had the lowest survival rate (20%), this rate being lower than that of macrophage-replete mice that had been passively immunized with naïve serum. Overall, anti-P. acnes antibodies did not prevent A. pleuropneumoniae infection under conditions of macrophage depletion (P > 0.05). Furthermore, in mice that had been passively immunized with anti-P. acnes serum, macrophage depletion resulted in a greater A. pleuropneumoniae burden and more severe pathological features of pneumonia in lung tissues than occurred in macrophage-replete mice. It was concluded that macrophages are essential for the process by which anti-P. acnes antibody prevents A. pleuropneumoniae infection in mice.

Identification and characterization of nucleotide variations in the genome of Ziziphus jujuba (Rhamnaceae) by next generation sequencing.

In this study, single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) in the genome of Ziziphus jujuba were identified using sequences generated by the Roche 454 GS-FLX sequencer. A total of, 573,141 reads were produced with an average read length of 360 bp. After quality control, 258,754 of the filtered reads were assembled into 23,864 contigs, and 293,458 remained as singletons. Using the contig assemblies as a reference, 17,160 SNPs and 478 InDels were identified. Among the SNPs, transitions occurred three times more frequently than transversions. In transitions, the number of C/T and G/A transitions was similar. Among the transversions, A/T was the most abundant, and C/G was much rarer than any of the other types of transversions, accounting for only about half the numbers of A/C, A/T and G/T transversions. For the InDels, mononucleotide changes amounted to 64.4% of the total number of InDels. In general, the frequency of detected InDels decreased as the length of the InDels increased. This study provides valuable marker resources for future genetic studies of Ziziphus spp.