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Jin K, Wang Y, Zhuo R, Xu J, Lu Z, Fan H, Huang B, Qiao G. TCP Transcription Factors Involved in Shoot Development of Ma Bamboo ( Dendrocalamus latiflorus Munro). FRONTIERS IN PLANT SCIENCE 2022; 13:884443. [PMID: 35620688 PMCID: PMC9127963 DOI: 10.3389/fpls.2022.884443] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 04/08/2022] [Indexed: 05/10/2023]
Abstract
Ma bamboo (Dendrocalamus latiflorus Munro) is the most widely cultivated clumping bamboo in Southern China and is valuable for both consumption and wood production. The development of bamboo shoots involving the occurrence of lateral buds is unique, and it affects both shoot yield and the resulting timber. Plant-specific TCP transcription factors are involved in plant growth and development, particularly in lateral bud outgrowth and morphogenesis. However, the comprehensive information of the TCP genes in Ma bamboo remains poorly understood. In this study, 66 TCP transcription factors were identified in Ma bamboo at the genome-wide level. Members of the same subfamily had conservative gene structures and conserved motifs. The collinear analysis demonstrated that segmental duplication occurred widely in the TCP transcription factors of Ma bamboo, which mainly led to the expansion of a gene family. Cis-acting elements related to growth and development and stress response were found in the promoter regions of DlTCPs. Expression patterns revealed that DlTCPs have tissue expression specificity, which is usually highly expressed in shoots and leaves. Subcellular localization and transcriptional self-activation experiments demonstrated that the five candidate TCP proteins were typical self-activating nuclear-localized transcription factors. Additionally, the transcriptome analysis of the bamboo shoot buds at different developmental stages helped to clarify the underlying functions of the TCP members during the growth of bamboo shoots. DlTCP12-C, significantly downregulated as the bamboo shoots developed, was selected to further verify its molecular function in Arabidopsis. The DlTCP12-C overexpressing lines exhibited a marked reduction in the number of rosettes and branches compared with the wild type in Arabidopsis, suggesting that DlTCP12-C conservatively inhibits lateral bud outgrowth and branching in plants. This study provides useful insights into the evolutionary patterns and molecular functions of the TCP transcription factors in Ma bamboo and provides a valuable reference for further research on the regulatory mechanism of bamboo shoot development and lateral bud growth.
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Lu Z, Qiu W, Jin K, Yu M, Han X, He X, Wu L, Wu C, Zhuo R. Identification and Analysis of bZIP Family Genes in Sedum plumbizincicola and Their Potential Roles in Response to Cadmium Stress. FRONTIERS IN PLANT SCIENCE 2022; 13:859386. [PMID: 35574076 PMCID: PMC9094143 DOI: 10.3389/fpls.2022.859386] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/29/2022] [Indexed: 05/23/2023]
Abstract
Sedum plumbizincicola (Crassulaceae), a cadmium (Cd)/zinc (Zn)/lead (Pb) hyperaccumulator native to Southeast China, is potentially useful for the phytoremediation of heavy metal-contaminated soil. Basic leucine zipper (bZIP) transcription factors play vital roles in plant growth, development, and abiotic stress responses. However, there has been minimal research on the effects of Cd stress on the bZIP gene family in S. plumbizincicola. In this study, 92 SpbZIP genes were identified in the S. plumbizincicola genome and then classified into 12 subgroups according to their similarity to bZIP genes in Arabidopsis. Gene structure and conserved motif analyses showed that SpbZIP genes within the same subgroup shared similar intron-exon structures and motif compositions. In total, eight pairs of segmentally duplicated SpbZIP genes were identified, but there were no tandemly duplicated SpbZIP genes. Additionally, the duplicated SpbZIP genes were mainly under purifying selection pressure. Hormone-responsive, abiotic and biotic stress-responsive, and plant development-related cis-acting elements were detected in the SpbZIP promoter sequences. Expression profiles derived from RNA-seq and quantitative real-time PCR analyses indicated that the expression levels of most SpbZIP genes were upregulated under Cd stress conditions. Furthermore, a gene co-expression network analysis revealed that most edge genes regulated by hub genes were related to metal transport, responses to stimuli, and transcriptional regulation. Because its expression was significantly upregulated by Cd stress, the hub gene SpbZIP60 was selected for a functional characterization to elucidate its role in the root response to Cd stress. In a transient gene expression analysis involving Nicotiana benthamiana leaves, SpbZIP60 was localized in the nucleus. The overexpression of SpbZIP60 enhanced the Cd tolerance of transgenic Arabidopsis plants by inhibiting ROS accumulation, protecting the photosynthetic apparatus, and decreasing the Cd content. These findings may provide insights into the potential roles of the bZIP family genes during the S. plumbizincicola response to Cd stress.
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Li S, Han X, Lu Z, Qiu W, Yu M, Li H, He Z, Zhuo R. MAPK Cascades and Transcriptional Factors: Regulation of Heavy Metal Tolerance in Plants. Int J Mol Sci 2022; 23:ijms23084463. [PMID: 35457281 PMCID: PMC9032930 DOI: 10.3390/ijms23084463] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/15/2022] [Accepted: 04/16/2022] [Indexed: 11/20/2022] Open
Abstract
In nature, heavy metal (HM) stress is one of the most destructive abiotic stresses for plants. Heavy metals produce toxicity by targeting key molecules and important processes in plant cells. The mitogen-activated protein kinase (MAPK) cascade transfers the signals perceived by cell membrane surface receptors to cells through phosphorylation and dephosphorylation and targets various effector proteins or transcriptional factors so as to result in the stress response. Signal molecules such as plant hormones, reactive oxygen species (ROS), and nitric oxide (NO) can activate the MAPK cascade through differentially expressed genes, the activation of the antioxidant system and synergistic crosstalk between different signal molecules in order to regulate plant responses to HMs. Transcriptional factors, located downstream of MAPK, are key factors in regulating plant responses to heavy metals and improving plant heavy metal tolerance and accumulation. Thus, understanding how HMs activate the expression of the genes related to the MAPK cascade pathway and then phosphorylate those transcriptional factors may allow us to develop a regulation network to increase our knowledge of HMs tolerance and accumulation. This review highlighted MAPK pathway activation and responses under HMs and mainly focused on the specificity of MAPK activation mediated by ROS, NO and plant hormones. Here, we also described the signaling pathways and their interactions under heavy metal stresses. Moreover, the process of MAPK phosphorylation and the response of downstream transcriptional factors exhibited the importance of regulating targets. It was conducive to analyzing the molecular mechanisms underlying heavy metal accumulation and tolerance.
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Xiao L, Hua F, Knops JMH, Zhao X, Mishra C, Lovari S, Alexander JS, Weckworth B, Lu Z. Spatial separation of prey from livestock facilitates coexistence of a specialized large carnivore with human land use. Anim Conserv 2022. [DOI: 10.1111/acv.12769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lu Z, Dong X, Fan Y, Liu W, Dai J, Han X, Liu J. Complete chloroplast genome of Toona ciliata Roem. var. pubescens (Franch.) Hand.-Mazz (Meliaceae), ‘Chinese mahogany’. Mitochondrial DNA B Resour 2022; 7:495-497. [PMID: 35311208 PMCID: PMC8933019 DOI: 10.1080/23802359.2022.2049987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Toona ciliata var. pubescens is classified as Toona subgenus of Meliaceae family, which belongs to a large deciduous tree species. It is also a kind of precious timber tree species and has a certain medicinal value. Here, the first complete chloroplast genome (cpDNA) sequence of T. ciliata var. pubescens was determined using the Illumina sequencing platform. The cpDNA genome is 159,481 bp in length, containing a large single-copy region (LSC) of 87,176 bp and a small single-copy region (SSC) of 18,381 bp, which were separated by a pair of inverted repeats (IRs) regions of 26,962 bp. The genome contains 138 genes, including 90 protein-coding genes, eight ribosomal RNA genes, and 40 transfer RNA genes. The phylogenetic analysis based on 19 cpDNA genomes showed a close relationship with Toona ciliate.
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Vanderpont AK, Lobson C, Lu Z, Luong K, Arentsen M, Vera T, Moore D, White MS, Prosser RS, Wong CS, Hanson ML. Fate of thiamethoxam from treated seeds in mesocosms and response of aquatic invertebrate communities. ECOTOXICOLOGY (LONDON, ENGLAND) 2022; 31:341-356. [PMID: 35000026 DOI: 10.1007/s10646-021-02500-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/23/2021] [Indexed: 06/14/2023]
Abstract
Thiamethoxam is a neonicotinoid insecticide widely applied in the Canadian Prairies. It has been detected in surface waters of agro-ecosystems, including wetlands, but the potential effects on non-target invertebrate communities in these wetlands have not been well characterized. In an effort to understand better the fate of thiamethoxam in wetlands and the response of invertebrates (zooplankton and emergent insects), model systems were used to mimic wetland flooding into planted fields. Outdoor mesocosms were treated with a single application of thiamethoxam-treated canola seeds at three treatment levels based on a recommended seeding rate (i.e., 6 kg/ha; 1×, 10×, and 100× seeding rate) and monitored over ten weeks. The mean half-life of thiamethoxam in the water column was 6.2 d. There was no ecologically meaningful impact on zooplankton abundances or community structure among treatments. Statistically significant differences were observed in aquatic insect abundance between control mesocosms and the two greatest thiamethoxam treatments (10× and 100× seeding rate). The observed results indicate exposure to thiamethoxam at environmentally relevant concentrations likely does not represent a significant ecological risk to abundance and community structure of wetland zooplankton and emergent insects.
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Diehl S, Kim A, Angelini G, Joo K, Adhikari S, Amaryan M, Arratia M, Atac H, Avakian H, Ayerbe Gayoso C, Baltzell NA, Barion L, Bastami S, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Brooks W, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clark L, Clary BA, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Dilks C, Djalali C, Dugger M, Dupre R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Filippi A, Forest T, Gavalian G, Gilfoyle GP, Girod FX, Glazier DI, Golubenko AA, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Hafidi K, Hakobyan H, Hattawy M, Hauenstein F, Hayward TB, Heddle D, Hicks K, Hobart A, Holtrop M, Hyde CE, Ireland DG, Isupov EL, Jo HS, Johnston R, Joosten S, Keller D, Khachatryan M, Khanal A, Kim W, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lee S, Lenisa P, Livingston K, Lu Z, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McKinnon B, Meziani ZE, Milner RG, Mineeva T, Mirazita M, Mokeev V, Moran P, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Naidoo P, Nanda S, Neupane K, Niccolai S, Niculescu G, O'Connell TR, Osipenko M, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Prok Y, Prokudin A, Raue BA, Ripani M, Ritman J, Rizzo A, Roberts CD, Rossi P, Rowley J, Sabatié F, Salgado C, Schmidt A, Segarra EP, Sharabian YG, Shrestha U, Simmerling P, Sokhan D, Soto O, Sparveris N, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Tezgin K, Thornton A, Tyler N, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei K, Wei X, Xu SS, Yale B, Zachariou N, Zhang J. Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region. PHYSICAL REVIEW LETTERS 2022; 128:062005. [PMID: 35213183 DOI: 10.1103/physrevlett.128.062005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 09/28/2021] [Accepted: 01/21/2022] [Indexed: 06/14/2023]
Abstract
High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7 GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.
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Huang Q, Qiu W, Yu M, Li S, Lu Z, Zhu Y, Kan X, Zhuo R. Genome-Wide Characterization of Sedum plumbizincicola HMA Gene Family Provides Functional Implications in Cadmium Response. PLANTS 2022; 11:plants11020215. [PMID: 35050103 PMCID: PMC8779779 DOI: 10.3390/plants11020215] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 11/26/2022]
Abstract
Heavy-metal ATPase (HMA), an ancient family of transition metal pumps, plays important roles in the transmembrane transport of transition metals such as Cu, Zn, Cd, and Co. Although characterization of HMAs has been conducted in several plants, scarcely knowledge was revealed in Sedum plumbizincicola, a type of cadmium (Cd) hyperaccumulator found in Zhejiang, China. In this study, we first carried out research on genome-wide analysis of the HMA gene family in S. plumbizincicola and finally identified 8 SpHMA genes and divided them into two subfamilies according to sequence alignment and phylogenetic analysis. In addition, a structural analysis showed that SpHMAs were relatively conserved during evolution. All of the SpHMAs contained the HMA domain and the highly conserved motifs, such as DKTGT, GDGxNDxP, PxxK S/TGE, HP, and CPx/SPC. A promoter analysis showed that the majority of the SpHMA genes had cis-acting elements related to the abiotic stress response. The expression profiles showed that most SpHMAs exhibited tissue expression specificity and their expression can be regulated by different heavy metal stress. The members of Zn/Co/Cd/Pb subgroup (SpHMA1-3) were verified to be upregulated in various tissues when exposed to CdCl2. Here we also found that the expression of SpHMA7, which belonged to the Cu/Ag subgroup, had an upregulated trend in Cd stress. Overexpression of SpHMA7 in transgenic yeast indicated an improved sensitivity to Cd. These results provide insights into the evolutionary processes and potential functions of the HMA gene family in S. plumbizincicola, laying a theoretical basis for further studies on figuring out their roles in regulating plant responses to biotic/abiotic stresses.
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Liu C, Lu Z, Chen L, Yang X, Xu J, Cui H, Zhu M. Predictive Value of Geriatric Nutritional Risk Index in Older Adult Cancer Patients. J Nutr Health Aging 2022; 26:153-156. [PMID: 35166307 DOI: 10.1007/s12603-022-1729-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIMS To compare the association of geriatric nutritional risk index (GNRI) and controlling nutritional status (CONUT) scores with malnutrition, and to study their association with clinical outcomes in older adult cancer patients. METHODS This retrospective analysis was conducted on 854 older adult cancer patients collected from 34 hospitals in 18 cities in China between June and September 2014. Anthropometric and hematological examination results at admission were collected, and subjective global assessment was used. Clinical outcomes, such as complications, length of hospital stays, and hospital costs, were recorded. Receiver operating characteristic curves were used to evaluate the accuracy of the two nutritional assessment tools for malnutrition. The association between GNRI and CONUT score and clinical outcomes was analyzed using the chi-square test, t-test, or rank sum test. RESULTS Among 854 patients with cancer, the prevalence of malnutrition was 42.7%. Compared with subjective global assessment, the GNRI had a significantly higher accuracy than the CONUT score in predicting malnutrition (area under the curve 0.704, 95% confidence interval, 0.658 - 0.750, P < 0.001). The GNRI was significantly associated with the occurrence of complications (χ2 = 4.985, P = 0.026), and low GNRI (≤98) was associated with a longer length of hospital stay (t = -2.179, P = 0.030). CONCLUSIONS The GNRI may be used to assess malnutrition in older adult cancer patients and can predict poor clinical outcomes in these patients.
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Shen X, Dong H, Jiang H, Cao H, Dowling R, Feng J, Lei Z, Zhao Y, Nui Z, Pu B, Lu Z, Gan Y. The global prevalence of sexual violence against pregnant women: a systematic review and meta-analysis. Women Health 2021; 62:37-45. [PMID: 34886757 DOI: 10.1080/03630242.2021.2011824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
When committed against pregnant women, sexual violence may have adverse health consequences for both the mother and the unborn child. To date, no studies have systematically summarized the global prevalence of sexual violence against pregnant women. We conducted a comprehensive search of PubMed, Embase and Web of Science from inception dates to January 2021 for studies reporting the prevalence of sexual violence against pregnant women. Prevalence was estimated using a random-effects meta-analysis. Heterogeneity was evaluated using the I2 statistic. Differences by study level characteristics were estimated through subgroup analysis and meta-regression. A total of 10 cross-sectional studies (a total of 8,439 participants) were included. The pooled proportion of sexual violence was 0.31 (95% CI: 0.22-0.40). Subgroup analyses showed higher prevalence of sexual violence against pregnant women in the 2010-2019 period (0.35, 95% CI0.15-7.53) and developing countries (0.32, 95% CI0.19-0.45). Almost one in three (31%) pregnant women around the world has been a victim of sexual violence in their lifetime. Sexual violence against pregnant women continues to be a major public health challenge. The global prevalence of sexual violence against pregnant women warrants the collective attention of the entire society.
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Lu Z, Hua K, Chen Y, Hu C. Standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery for sacrocolpopexy. BJOG 2021; 129:1004-1007. [PMID: 34839566 DOI: 10.1111/1471-0528.17030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2021] [Indexed: 02/03/2023]
Abstract
We describe the standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for sacrocolpopexy in women with uterine prolapse. In this video, we demonstrate the key techniques: identifying the right hypogastric nerve (rHN) before opening the pelvic peritoneum; removing the fat and loose connective tissue along the rHN to expose the presacral fascia; incising the presacral fascia to reach the presacral space to expose the middle sacral vasculature and the anterior longitudinal ligament (ALL) of the first sacral vertebra (S1) below the promontory; attaching the mesh to the ALL to avoid vessel injury; and completing the peritonealisation.
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Li K, Feng J, Yuan X, Gan L, Lu Z, Xiong R. Study on a new manner of the magnetization switching actuated by a unidirectional pulse current. NANOTECHNOLOGY 2021; 33:025001. [PMID: 34614479 DOI: 10.1088/1361-6528/ac2d48] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 10/06/2021] [Indexed: 06/13/2023]
Abstract
A new writing scheme with a unidirectional pulse current is proposed for spin transfer torque (STT) based magnetic random-access memory (MRAM). To investigate the feasibility of the writing scheme, bilayered nano-pillars composed of a soft layer with small in-plane shape anisotropy and a hard layer with either large perpendicular anisotropy (PMA) or in-plane anisotropy (IMA) are designed and their switching behaviors are studied. It is found that in either type of bilayered nano-pillars, with the aid of the attached hard layer, the magnetization of the soft layer can be switched back and forth under a unidirectional pulse current. In an IMA/IMA nano-pillar, the magnetization of the free layer (FL) can achieve excellent alignment, which is in contrast to the IMA/PMA nano-pillar. By optimizing the dimensions and magnetic parameters of the IMA/IMA nano-pillar, a decently low switching current density (4.3 × 1011A m-2) and ultrashort switching time (<1 ns) can be reached. Based on these results, the unidirectional writing scheme is practical if an IMA/IMA bilayer is used to replace the FL in a magnetic tunnel junction. Considering that a unidirectional writing scheme can enable the application of materials with high spin polarization such as half metals, and avoid the injection of writing current into junction using a special design, it may be very promising for STT-MRAM.
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Lu Z, Tilly MJ, Aribas E, Bos D, De Knegt R, Ikram MA, De Groot NMS, Voortman T, Kavousi M. Imaging-based body fat depots and new-onset atrial fibrillation in general population. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Background
Obesity is a well-established risk factor for incident atrial fibrillation (AF). Whether different body fat depots differentially associate with AF development remains largely unknown.
Purpose
We aimed to investigate the associations between various body fat depots and the risk of new-onset AF among middle-aged and elderly individuals from general population.
Methods
In the prospective population-based cohort study, body composition was assessed using dual-energy X-ray absorptiometry (DXA) and total body mass, lean mass, fat mass, android and gynoid fat were analyzed (N=3468). Liver fat and epicardial fat were assessed using computed tomography (CT) (N=2145). A body fat score was defined by adding tertiles of each fat depot. All participants were followed for the occurrence of AF until 1st Jan. 2014. Principle component analysis was conducted to identify body fat distribution patterns. Time-to-event analyses were performed using Cox proportional hazards regression analysis. Hazard ratios (HR) and 95% confidence-intervals (95% CI), adjusted for cardiovascular risk factors, were calculated.
Results
Mean (standard deviation) of age for participants in DXA study and CT study was 74.42 (6.85) and 68.66 (6.41) years, respectively. AF incidence rate was 13.1 per 1000 person-years during a median follow-up time of 9.62 years. In the adjusted model, fat mass (HR; 95% CI: 1.33; 1.05–1.68), lean mass (1.40; 1.15–1.72), gynoid fat mass (1.36; 1.12–1.65), and total body mass (1.51; 1.21–1.89) were significantly associated with new-onset AF. Of note, android-to-gynoid fat ratio was inversely associated with incident AF (HR; 95% CI: 0.81; 0.70–0.94). Larger body fat score was associated with increased risk of incident AF (P for trend <0.01). Two fat distribution patterns were identified. Adherence to the fat- and gynoid fat- pattern (P for trend = 0.035), but not muscle- and visceral fat- pattern (P for trend = 0.35), was significantly associated with larger risk of new-onset AF.
Conclusions
Various body fat depots were associated with new-onset AF. Larger values of total body mass carried the highest risk for incident AF. The inverse association between android to gynoid fat ratio with AF presents a novel finding. A significant dose-response relationship between body fat accumulation and risk of new-onset AF was observed, implying a collective impact of fat depots on AF development. Findings also suggest that various fat depots, characterized by different fat distribution patterns, may exert differential combined effect on the risk of incident AF.
Funding Acknowledgement
Type of funding sources: None. Fat depots and atrial fibrillation
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Zhang B, Yu D, Lu Z. Constipation is associated with worse prognosis of thrombolytic AIS: a single-center prospective study. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Background and purpose
Previous clinical studies have found that constipation was associated with the prognosis of ischemic stroke patients. This information may provide new ideas for thrombolytic AIS (acute cerebral arterial thrombosis) patients' short-term prognostic assessment. Our study was designed to investigate the risk factors of constipation and its association with the prognosis in thrombolytic AIS patients.
Methods
The prospective cohort study included 97 AIS patients treated with intravenous thrombolysis. Three days without defecation in thrombolytic patients was recorded as constipation in clinic. The risk factors for constipation included demographics, clinical characteristics, laboratory parameters and partial treatments. Scores of NIHSS and mRS and length of stay (LOS) in ICU and hospital were used to evaluate the effect of constipation on patients' neurological function and short-term prognosis.
Results
The incidence of constipation was 49.48% in the first three days after intravenous thrombolysis. The use of stomach tube and antibiotics made patients more prone to constipation (odds ratio OR: 5.01, 95% CI: 2.04–12.32, P=0.000; odds ratio: 6.06, 95% CI: 2.35–15.61, P=0.000). The occurrence of constipation resulted in significantly longer ICU and hospital LOS (2.29±1.63 versus 4.75±4.22, P=0.000; 11.08±10.01 versus 15.73±12.36, P=0.044). Moreover, constipation worsened the thrombolytic AIS patients' short-term neurological recovery (mRS at 3 months: 1.53±1.72 versus 2.41±1.92, P=0.02). Oral probiotics for constipation during hospitalization not only prolonged patients' stay in the ICU (2.91±2.28 versus 6.44±4.88, P=0.003), but also resulted in poorer short-term neurological functional outcomes (mRS at 3 months: 1.57±1.53 versus 3.26±1.91, P=0.002).
Conclusions
The occurrence of constipation in the first three days was associated with the longer ICU and hospital stay and a worse short-term prognosis, suggesting that constipation may be a predictor of thrombolytic AIS patients' prognosis. Further studies of constipation and its appropriate therapy strategy are needed to solve the plight of thrombolytic AIS with constipation.
Funding Acknowledgement
Type of funding sources: None.
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Tilly MJ, Lu Z, Geurts S, Ikram MA, De Maat MPM, Ikram MK, De Groot NMS, Kavousi M. Distribution and risk profile of atrial fibrillation patterns among women and men from the general population. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
In a clinical setting, atrial fibrillation (AF) subgroups are defined, including paroxysmal, persistent, and permanent AF. These subgroups differ in terms of clinical characteristics, management strategy, and long-term outcomes. Application of clinical classifications in population-based settings is challenging as they are based on the duration of symptoms, recurrence, and treatment.
Purpose
We aim to develop an objective and standardized classification for AF patterns in the general population and examine the associated cardiovascular risk profiles and outcomes for the identified AF patterns.
Methods
Participants with only one reported AF episode were categorized as single-documented AF, if at least two separate AF episodes were reported as multiple-documented AF and as longstanding persistent AF if at least two consecutive ECG's at the research center showed AF, not followed by an ECG showing sinus rhythm. We fitted mixed effect models with age as time scale to characterize sex-specific cardiovascular risk factor trajectories preceding each AF pattern. We further used Cox proportional hazard modelling to describe the risk of coronary heart disease (CHD), heart failure (HF), stroke, and all-cause mortality following AF.
Results
We included 14,620 men and women aged ≥45 years. 1137 participants were categorized as single-documented AF, 208 as multiple-documented AF, and 57 as longstanding persistent AF. We identified significant differences in the preceding trajectories of weight, body mass index, systolic blood pressure, diastolic blood pressure, waist circumference, hip circumference, and waist-hip ratio with various AF patterns. In general, both men and women with persistent-elevated levels of these risk factors were prone to longstanding persistent AF.
AF was associated with a large risk for subsequent CHD, HF, stroke, and mortality in the general population. Among the different AF patterns, single-documented AF conferred the largest risk of CHD [hazard ratio, 95% confidence interval: 1.92 (1.19–3.03)] and mortality [1.70 (1.41–2.07)] as compared to multiple-documented AF, and as compared to longstanding persistent AF [1.45 (0.72–2.90) and 3.66 (2.25–5.95), respectively].
Conclusion
We developed a classification for AF patterns within a general population. We identified differences in risk factor trajectories preceding each AF pattern, which implies differences in pathophysiological mechanisms underlying AF. Participants with single-documented AF showed worse prognosis than those with multiple AF episodes. This might be due to the subgroup definition, since participants should live for a longer period of time to be categorized in the multiple-documented AF and longstanding persistent AF groups. This can also imply that participants suffering from multiple AF episodes are more frequently monitored, and treated for other risk factors. However, this could also suggest that singular AF episodes are not as innocent as commonly thought.
Funding Acknowledgement
Type of funding sources: Public hospital(s). Main funding source(s): - Erasmus MC Mrace grant. - Netherlands Organization for the Health Research and Development (ZonMw) Figure 1Figure 2. Progosis of various AF patterns
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Zhang B, Zhu Q, Lu Z. Prognostic nutrition index predicts outcomes in critically ill stroke patients: a database-based cohort study. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Although there are many indicators to assess nutritional status, a more comprehensive and objective indicator is still needed in clinical practice. In this study, we evaluated the relationship between the prognostic nutritional index (PNI) and clinical outcomes in patients with critically ill stroke.
Methods
Subjects who were diagnosed as stroke in the Beth Israel Deaconess Medical Center between 2001 and 2012 were identified from the Medical Information Mart for Intensive Care (MIMIC) III database. PNI was calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm3). The multivariate logistic regression and the Cox regression analysis were performed to assess the impact of PNI on 3-month and 4-year mortality in stroke patients.
Results
A total of 624 subjects were included in this study. Compared with the high-PNI group, those in the Low PNI group had lower body mass index (BMI), hemoglobin, neutrophil count, lymphocyte count and albumin. On the contrary, Age, Blood urea nitrogen (BUN), Creatinine (Cre), simplified acute physiologic scoreII (SAPSII) score and sequential organ failure assessment (SOFA) score of the low PNI group were higher than the high PNI group. After adjusting for other confounders, PNI was independently associated with 3-month mortality (adjusted odds ratio = 1.910; 95% confidence interval, 1.244–2.933; P=0.003). By the Kaplan-Meier analysis, patients in the low PNI group presented significantly shorter survival time and higher death rate. The Cox regression model indicated low PNI as an independent risk factor of 4-year all-cause mortality of stroke patients (hazard ratio = 1.824; 95% CI, 1.340–2.483; P<0.001).
Conclusions
Low PNI is independently associated with short-term and long-term prognosis in patients with critically ill stroke.
Funding Acknowledgement
Type of funding sources: None.
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Lu Z, Tilly M, Aribas E, Roeters Van Lennep J, Ikram M, De Groot N, Van Rosmalen J, Kavousi M. Trajectories of metabolic risk factors and risk of new-onset atrial fibrillation among men and women. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.0584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Atrial fibrillation (AF) is the most common cardiac arrhythmia with major public health impact. Obesity and hypertension are among the most important risk factors to AF development. The link between AF and its pathogenetic factors are complex and comprehensive assessment of the impact of various long-term trajectories of anthropometric measures and blood pressure on incident AF among men and women is sparse.
Purpose
To investigate sex-specific trajectories of various anthropometric measures and blood pressure at population level, and further assess the impact of these trajectories on incident AF.
Methods
We included 5263 participants (mean age 72.1 years) with available repeated assessments measured 2 to 4 times for weight, body mass index (BMI), hip circumference (HC), waist circumference (WC), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) and mean arterial pressure (MAP). Latent class linear mixed model with age as the time scale were fitted to identify the potential various classes in each risk factor. Cox proportional hazards regression models were used to assess the association between risk factors' trajectories and risk of new-onset AF, with the most favorable trajectory as a reference. Models were adjusted for traditional cardiovascular risk factors.
Results
2159 (41.0%) of all participants were men. Median follow-up time was 9.76 years during which the incidence rate of AF was 16.2 per 1000 person-years for men, and 11.3 per 1000 person-years for women. In full-adjusted model, various trajectories of BMI, HC, and MAP were significantly associated with incident AF among men, and trajectories of weight, BMI, WC, HC, SBP, PP and MAP were significantly associated with incident AF among women. For BMI, persistent-increasing BMI trajectory carried the highest risk for AF with hazard ratio (HR) and 95% confidence interval (95% CI) of 1.39 (1.05–1.85) in men and 1.60 (1.19–2.15) in women. Also, persistently increasing trajectories of weight [1.69 (1.20–2.37)], WC [1.39 (1.04–1.86)] and HC [1.56 (1.05–2.34)] among women conferred the largest risks. For SBP, the persistently hypertensive trajectory carried the largest risk for AF among women [2.06 (1.25–3.39)], while intensively increasing SBP trajectory conferred the largest risk among men [1.34 (0.89–2.02)], albeit non-significant. Similar associations were observed for MAP among men and women; associated risks were 1.77 (1.25–2.51) for the persistent-hypertensive trajectory in women and 1.64 (1.16–2.33) for the intensive-increasing trajectory in men.
Conclusions
Various trajectories of metabolic risk factors were associated with new-onset AF among men and women. Sex-specific associations between SBP and MAP with AF could imply the differential long-term impact of vascular function on AF development among men and women. This highlights the importance of sex-specific preventive strategies for AF in general population.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): Gender and Prevention grant, ZonMwCSC scholarship for PhD research
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Zhou C, Xiong A, Miao L, Chen J, Li K, Liu H, Ma Z, Wang H, Lu Z, Shen J, Zhao J, Li W, Bi M, Zhang J, Xing L. P51.03 Oritinib (SH-1028), a Third-generation EGFR-TKI in Advanced NSCLC Patients with Positive EGFR T790M: Results of a Single-arm Phase Ib Trial. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Sun J, Liu H, Dang L, Liu J, Wang J, Lu Z, Lu Y. Genome shuffling of Lactobacillus plantarum 163 enhanced antibacterial activity and usefulness in preserving orange juice. Lett Appl Microbiol 2021; 73:741-749. [PMID: 34562034 DOI: 10.1111/lam.13566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/25/2021] [Accepted: 09/17/2021] [Indexed: 01/04/2023]
Abstract
Lactic acid bacteria have been used to inhibit the growth of spoilage bacteria in food and animal feeds. For instance, Lactobacillus plantarum 163 can inhibit efficiently the growth of both gram-positive and gram-negative bacteria. In our study, the antibacterial activity of L. plantarum 163 was further improved significantly by genome shuffling. The optimal conditions for protoplast formation and regeneration were 20 mg ml-1 lysozyme and 5 mg ml-1 mutanolysin for 30 min at 37°C using 0·5 mol l-1 sucrose as stabilizer. The protoplasts were inactivated under ultraviolet light for 120 s or heated at 58°C for 20 min. After two rounds of genome shuffling, the inhibitory activity of strain F2-14 was improved by 2·45- and 1·99-fold, respectively, as compared to their parent strains. The prepared antibacterial peptides supernatant (APS) was added to the orange juice to inhibit spores of Alicyclobacillus acidoterrestris (SAA) at 45 and 28°C. Results showed that the growth of A. acidoterrestris was significantly inhibited, and the decrease in total soluble solids, OD value and pH value was also delayed. After treatment with APS, the thermal sensitivity of spores was increased and its D value was reduced to 13·78, 3·87 and 1·47 min at 80, 90 and 95°C respectively.
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Zhang Y, Betran AP, Li X, Liu D, Yuan N, Shang L, Lin W, Tu S, Wang L, Wu X, Zhu T, Zhang Y, Lu Z, Zheng L, Gu C, Fang J, Liu Z, Ma L, Cai Z, Yang X, Li H, Zhang H, Zhao X, Yan L, Wang L, Sun X, Luo Q, Liu L, Zhu J, Qin W, Yao Q, Dong S, Yang Y, Cui Z, He Y, Feng X, He L, Zhang H, Zhang L, Wang X, Souza JP, Qi H, Duan T, Zhang J. What is an appropriate caesarean delivery rate for China: a multicentre survey. BJOG 2021; 129:138-147. [PMID: 34559941 PMCID: PMC9297886 DOI: 10.1111/1471-0528.16951] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2021] [Indexed: 11/30/2022]
Abstract
Objective To assess the current status of caesarean delivery (CD) in China, propose reference CD rates for China overall, and by regions, investigate the main indications for CDs and identify possible areas for safe reduction. Design A multicentre cross‐sectional study. Setting A total of 94 hospitals across 23 provinces in China. Population A total of 73 977 randomly selected deliveries. Methods We used a modified Robson classification to characterise CDs in subgroups and by regions, and the World Health Organization (WHO) C‐Model to calculate reference CD rates. Main outcome measures CD rates in China. Results In 2015–2016, the overall CD rate in China was 38.9% (95% CI 38.6–39.3%). Considering the obstetric characteristics of the population, the multivariable model‐based reference CD rate was estimated at 28.5% (95% CI 28.3–28.8%). Accordingly, an absolute reduction of 10.4% (or 26.7% relative reduction) may be considered. The CD rate varied substantially by region. Previous CD was the most common indication in all regions, accounting for 38.2% of all CDs, followed by maternal request (9.8%), labour dystocia (8.3%), fetal distress (7.7%) and malpresentation (7.6%). Overall, 12.7% of women had prelabour CDs, contributing to 32.8% of the total CDs. Conclusions Nearly 39% of births were delivered by caesarean in China but a reduction of this rate by a quarter may be considered attainable. Repeat CD contributed more than one‐third of the total CDs. Given the large variation in maternal characteristics, region‐specific or even hospital‐specific reference CD rates are needed for precision management of CD. Tweetable abstract The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%. The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%. Linked article This article is commented on by M Varner, p. 148 in this issue. To view this mini commentary visit https://doi.org/10.1111/1471-0528.16953.
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Zhao R, Lu Z, Cai S, Gao T, Xu S. Whole genome survey and genetic markers development of crocodile flathead Cociella crocodilus. Anim Genet 2021; 52:891-895. [PMID: 34486145 DOI: 10.1111/age.13136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 11/30/2022]
Abstract
Flatheads in family Platycephalidae are ecologically and commercially important marine fish species in the Indo-West Pacific. Due to similar morphological characters, the taxonomy and phylogenetics of flatheads are in confusion. Studies on phylogenetics and molecular marker development are required to discriminate congeners of flatheads. In the present study, we performed whole genome survey sequencing of crocodile flathead Cociella crocodilus to provide genomic information and genetic markers of this species. In total, 54.03 Gb of clean genomic data were generated. The genome size was estimated to be 732.99 Mb with the heterozygosity ratio of 0.73% and the repeat sequence ratio of 33.48%. The preliminary assembled genome sequences were 794.07 Mb with contig N50 of 1504 bp. We detected 2 624 875 genome-wide SNPs with transition/transversion ratio of 1.422. A total of 313 842 microsatellite motifs were identified, most of which were dinucleotide motifs with a frequency of 74.89%. In addition, we assembled the complete mitogenome of C. crocodilus and subsequent phylogenetic analysis were performed. Phylogenetic analyses revealed numbers of polyphyletic groups in family Platycephalidae. The reported genomic data and genetic markers in our study should be useful in further phylogeny and phylogenomics studies of flathead species.
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Wang C, Liu Z, Chen X, Qiao J, Li L, Lu Z, Sun X. 179P Neoadjuvant camrelizumab plus nab-paclitaxel and epirubicin for early triple-negative breast cancer: A single-arm, open-label, phase II study. Ann Oncol 2021. [DOI: 10.1016/j.annonc.2021.08.460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Ji J, Zhou L, Xu Z, Ma L, Lu Z. Two atypical gram-negative bacteria-binding proteins are involved in the antibacterial response in the pea aphid (Acyrthosiphon pisum). INSECT MOLECULAR BIOLOGY 2021; 30:427-435. [PMID: 33928689 DOI: 10.1111/imb.12708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/26/2021] [Accepted: 04/21/2021] [Indexed: 06/12/2023]
Abstract
The activation of immune pathways is triggered by the recognition of pathogens by pattern recognition receptors (PRRs). Gram-negative bacteria-binding proteins (GNBPs)/β-1,3-glucan recognition proteins (βGRPs) are a conserved family of PRRs in insects. Two GNBPs are predicted in the genome database of pea aphids; however, little is known about their functions in the aphid immune system. Here, we show that pea aphid GNBPs possess domain architectures and sequence features distinct from those of typical GNBPs/βGRPs and that their expression is induced by bacterial infection. Knockdown of their expression by dsRNA resulted in lower phenoloxidase activity, higher bacterial loads and higher mortality in aphids after infection. Our data suggest that these two atypical GNBPs are involved in the antibacterial response in the pea aphid, likely acting as PRRs in the prophenoloxidase pathway.
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Xu D, Lu Z, Jin K, Qiu W, Qiao G, Han X, Zhuo R. SPDE: A Multi-functional Software for Sequence Processing and Data Extraction. Bioinformatics 2021; 37:3686-3687. [PMID: 33848326 DOI: 10.1093/bioinformatics/btab235] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/18/2021] [Accepted: 04/10/2021] [Indexed: 11/14/2022] Open
Abstract
SUMMARY Sequence Processing and Data Extraction (SPDE) has eight modules comprising 100 basic functions ranging from sequence extraction, format conversion to data reorganization and mining, and all of these functions can be completed by point-and-click icons. SPDE also incorporates eight public analyses tools; thus, SPDE is a comprehensive bioinformatics platform for big biological data analysis. AVAILABILITY AND IMPLEMENTATION SPDE built by Python can run on 32-bit, 64-bit Windows and MacOS systems. It can be downloaded from https://github.com/simon19891216/SPDEv1.2.git. SUPPLEMENTARY INFORMATION The test data and video tutorials can be downloaded from https://github.com/simon19891216/SPDEv1.2.git.
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Sun J, Liu Y, Lin F, Lu Z, Lu Y. CodY, ComA, DegU and Spo0A controlling lipopeptides biosynthesis in Bacillus amyloliquefaciens fmbJ. J Appl Microbiol 2021; 131:1289-1304. [PMID: 33460520 DOI: 10.1111/jam.15007] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 01/09/2023]
Abstract
AIM In the study, we investigated the regulatory effects of these genes (codY, comA, degU and spo0A) on the biosynthesis of three lipopeptides (bacillomycin D, fengycin and surfactin) in Bacillus amyloliquefaciens. METHODS AND RESULTS The codY, comA, degU and spo0A genes in B. amyloliquefaciens fmbJ were knocked out. The results showed that the productions of bacillomycin D were significantly reduced compared with that of fmbJ. Their deletion induced great changes in the levels of transcripts specifying metabolic pathways, quorum sensing system and substance transport system in fmbJ. Moreover, overexpression of these genes improved the productions of bacillomycin D. In particular, the overexpression of spo0A enhanced bacillomycin D yield up to 648·9 ± 60·9 mg l-1 from 277·3 ± 30·5 mg l-1 . In addition, the yields of surfactin in fmbJΔcodY and fmbJΔdegU were significantly improved, and the regulatory factor CodY had no significant effect on the synthesis of fengycin. CONCLUSIONS These genes positively regulated the expression of bacillomycin D and fengycin synthase genes in strain fmbJ. However, codY and degU negatively regulated surfactin biosynthesis. Moreover, it was found that CodY had a concentration dependence on bacillomycin D synthesis. Spo0A might play a direct regulatory role in the synthesis and secretion of bacillomycin D. SIGNIFICANCE AND IMPACT OF THE STUDY This study indicated that genetic engineering of regulatory genes was an effective strategy to improve the yields of antimicrobial lipopeptides and provided promising strains for industrial production of lipopeptides.
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