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Bacillus spp. are probiotics and can secrete a variety of natural antimicrobiol active substances, of which lipopeptides are an important class. Up to now, about 90 lipopeptides have been identified, and most of them are cyclic lipopeptides. surfactin, iturin, fengycin, bacillomycin and polymyxins are widely studied, and the first three have huge potential for application due to their properties of surfactants and anti-fungal, anti-bacterial, anti-viral, anti-tumor and anti-inflammatory functions. In this paper, the research progress in the structure, function, synthesis regulation, separation, purification and production of surfactin, iturin and fengycin was reviewed. Synthetic biology is a vital means to increase the yield of lipopeptides, and in the future, lipopeptides can be used in crop cultivation, animal farming, food, medicine and petroleum industries as well as environmental protection. Future research should be strengthened on the discovery of new lipopeptides, synthesis of high-activity lipopeptides, economical production of lipopeptides on a large scale and their safety evaluation.

Background: During the bread wheat speciation by polyploidization, a series of genome rearrangement and sequence recombination occurred. Simple sequence repeat (SSR) sequences, predominately located in heterochromatic regions of chromosomes, are the effective marker for tracing the genomic DNA sequence variations. However, to date the distribution dynamics of SSRs on chromosomes of bread wheat and its donors, including diploid and tetraploid Triticum urartu, Aegilops speltoides, Aegilops tauschii, Triticum turgidum ssp. dicocoides, reflecting the genome evolution events during bread wheat formation had not been comprehensively investigated., Results: The genome evolution was studied by comprehensively comparing the distribution patterns of (AAC) n , (AAG) n , (AGC) n and (AG) n in bread wheat Triticum aestivum var. Chinese Spring and its progenitors T. urartu, A. speltoides, Ae. tauschii, wild tetroploid emmer wheat T. dicocoides, and cultivated emmer wheat T. dicoccum. Results indicated that there are specific distribution patterns in different chromosomes from different species for each SSRs. They provided efficient visible markers for identification of some individual chromosomes and SSR sequence evolution tracing from the diploid progenitors to hexaploid wheat. During wheat speciation, the SSR sequence expansion occurred predominately in the centromeric and pericentromeric regions of B genome chromosomes accompanied by little expansion and elimination on other chromosomes. This result indicated that the B genome might be more sensitive to the "genome shock" and more changeable during wheat polyplodization., Conclusions: During the bread wheat evolution, SSRs including (AAC) n , (AAG) n , (AGC) n and (AG) n in B genome displayed the greatest changes (sequence expansion) especially in centromeric and pericentromeric regions during the polyploidization from Ae. speltoides S genome, the most likely donor of B genome. This work would enable a better understanding of the wheat genome formation and evolution and reinforce the viewpoint that B genome was originated from S genome.

Background: We have shown that genetic overexpression of cell cycle proteins can increase the proliferation of transplanted cardiomyocytes derived from human induced-pluripotent stem cells (hiPSC-CMs) in animal models of myocardial infarction (MI). Here, we introduce a new, non-genetic approach to promote hiPSC-CM cell cycle activity and proliferation in transplanted human cardiomyocyte patches (hCMPs)., Methods: Mice were randomly distributed into 5 experimental groups (n = 10 per group). One group underwent Sham surgery, and the other 4 groups underwent MI induction surgery followed by treatment with hCMPs composed of hiPSC-CMs and nanoparticles that contained CHIR99021 and FGF1 (the NP CF -hCMP group), with hCMPs composed of hiPSC-CMs and empty nanoparticles (the NP E -hCMP group); with patches containing the CHIR99021/FGF-loaded nanoparticles but lacking hiPSC-CMs (the NP CF -Patch group), or patches lacking both the nanoparticles and cells (the E-Patch group). Cell cycle activity was evaluated via Ki67 and Aurora B expression, bromodeoxyuridine incorporation, and phosphorylated histone 3 levels (immunofluorescence); engraftment via human cardiac troponin T or human nuclear antigen expression (immunofluorescence) and bioluminescence imaging; cardiac function via echocardiography; infarct size and wall thickness via histology; angiogenesis via isolectin B4 expression (immunofluorescence); and apoptosis via TUNEL and caspace 3 expression (immunofluorescence)., Results: Combined CHIR99021- and FGF1-treatment significantly increased hiPSC-CM cell cycle activity both in cultured cells (by 4- to 6-fold) and in transplanted hCMPs, and compared to treatment with NP E -hCMPs, NP CF -hCMP transplantation increased hiPSC-CM engraftment by ~4-fold and was associated with significantly better measurements of cardiac function, infarct size, wall thickness, angiogenesis, and hiPSC-CM apoptosis four weeks after MI induction., Conclusions: Nanoparticle-mediated CHIR99021 and FGF1 delivery promotes hiPSC-CM cell cycle activity and proliferation, as well as the engraftment and regenerative potency of transplanted hCMPs, in a mouse MI model., Competing Interests: Declaration of Competing Interest The authors have declared that no conflict of interest exists., (Copyright © 2020. Published by Elsevier Ltd.)

Background: Cardiomyocytes that have been differentiated from CCND2-overexpressing human induced-pluripotent stem cells (hiPSC-CCND2 OE CMs) can proliferate when transplanted into mouse hearts after myocardial infarction (MI). However, it is unknown whether remuscularization can replace the thin LV scar and if the large muscle graft can electrophysiologically synchronize to the recipient myocardium. Our objectives are to evaluate the structural and functional potential of hiPSC-CCND2 OE CMs in replacing the LV thin scar., Methods: NOD/SCID mice were treated with hiPSC-CCND2 OE CMs (i.e., the CCND2 OE group), hiPSC-CCND2 WT CMs (the CCND2 WT group), or an equal volume of PBS immediately after experimentally-induced myocardial infarction. The treatments were administered to one site in the infarcted zone (IZ), two sites in the border zone (BZ), and a fourth group of animals underwent Sham surgery., Results: Six months later, engrafted cells occupied >50% of the scarred region in CCND2 OE animals, and exceeded the number of engrafted cells in CCND2 WT animals by ~8-fold. Engrafted cells were also more common in the IZ than in the BZ for both cell-treatment groups. Measurements of cardiac function, infarct size, wall thickness, and cardiomyocyte hypertrophy were significantly improved in CCND2 OE animals compared to animals from the CCND2 WT or PBS-treatment groups. Measurements in the CCND2 WT and PBS groups were similar, and markers for cell cycle activation and proliferation were significantly higher in hiPSC-CCND2 OE CMs than in hiPSC-CCND2 WT CMs. Optical mapping of action potential propagation indicated that the engrafted hiPSC-CCND2 OE CMs were electrically coupled to each other and to the cells of the native myocardium. No evidence of tumor formation was observed in any animals., Conclusions: Six months after the transplantation, CCND2-overexpressing hiPSC-CMs proliferated and replaced >50% of the myocardial scar tissue. The large graft hiPSC-CCND2 OE CMs also electrically integrated with the host myocardium, which was accompanied by a significant improvement in LV function., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We evaluated the efficacy of bioresorbable sternal reinforcement device (poly-L-lactide sternal pins) on sternal healing after median sternotomy in young children (with body weight less than 10 kg) with congenital heart disease (CHD). Data from 85 patients, who underwent CHD surgery through median sternotomy from October 2016 to May 2018, were collected and analyzed. Sternal pins were utilized in 85 patients (10 mm × 1 mm × 1 mm for patients with body weights less than 5 kg and 15 mm × 2 mm × 2 mm for those weighing between 5 and 10 kg) in addition to sternum closure with Ethicon PDS TM II running sutures (Group A), while 84 patients received the Ethicon sternal closure (Group B) with no pins. The occurrence of sternal dehiscence, anterior-posterior displacement, and high-low displacement was evaluated by physical examination and three-dimensional computed tomography at one month postoperatively. No anterior-posterior sternal displacement (0%) was observed in Group A, while 10 anterior-posterior displacements (11.9%) were observed in Group B (P < 0.01). The number of sternal caudal-cranial displacements in Groups A and B was 4 (4.71%) and 5 (5.35%), respectively (P = 0.870). While no sternal dehiscence (0%) was observed in Group A, 7 out of 84 patients (8.33%) in Group B exhibited obvious sternal dehiscence (P < 0.01). The bioresorbable poly-L-lactide sternal pins reduced an anterior-posterior sternal displacement and sternal dehiscence, which was accompanied by a significant improvement of an early sternal fixation.

The demand for alternatives to antibiotics to improve the growth performance of food animals is increasing. Defensins constitute the first line of defence against pathogens in the innate immune system of animals and humans. A transgenic Chlorella ellipsoidea strain producing mNP-1 (a mutated rabbit defensin NP-1) was previously obtained in our laboratory. In this study, a process for producing the transgenic strain on a large scale was developed, and the C. ellipsoidea strain producing mNP-1 was used as a feed additive to improve the health and growth performance of chickens. The volume of C. ellipsoidea producing mNP-1 can be scaled up to 10,000 L with approximately 100 g/L dry biomass, and the mNP-1 content of transgenic microalgal powder (TMP) was 90-105 mg/L. A TMP-to-regular feed ratio of 1‰, as the optimal effective dose, can promote the growth of broiler chickens by increasing weight by 9.27-12.95%. mNP-1 can improve duodenum morphology by promoting long and thin villi and affect the microbial community of the duodenum by increasing the diversity and abundance of beneficial microbes. These results suggested that transgenic Chlorella producing mNP-1 can be industrially produced and used as an effective feed additive and an alternative to antibiotics for improving the health and growth performance of broiler chickens or other types of food animals/poultry.

The BES1 transcription factor family play a central role in brassinosteroid signaling pathway that regulates a wide range of plant growth and developmental processes, as well as resistances to various stresses. However, no comprehensive study of the BES1 gene family in soybean has been reported. In this work, 16 GmBES1 -like genes were identified in soybean, which could be divided into two clades based on their phylogenetic relationships, gene structures and motif compositions. We then examined their duplication status and evolutionary models. The result showed that most of the GmBES1 -like genes have duplicated counterparts generated from the recent Glycine WGD event, and these genes are originated from 6 distinct ancestors before the Gamma WGT event. We further studied the expression profiles of GmBES1 -like genes, and found their spatio-temporal and stressed expression patterns varied tremendously. For example, GmBES1-5 and GmBES1-6 were highly expressed in almost every sample, whereas GmBES1-7 and GmBES1-8 were not expressed. Additionally, interaction network analysis revealed the presence of 3 clusters between GmBES1- like genes and other associated genes, implying that they have both the conserved and divergent functions. Lastly, we analyzed the genetic diversity of GmBES1- like genes in 302 resequenced wild, landrace and improved soybean accessions. It showed that most of these genes are well conserved, and they are not changed during domestication and improvement. These results provide insights into the characterization of GmBES1 family and lay the foundation for further functional study of such genes.

Background: Rodent hearts can regenerate myocardium lost to apical resection or myocardial infarction for up to 7 days after birth, but whether a similar window for myocardial regeneration also exists in large mammals is unknown., Methods: Acute myocardial infarction (AMI) was surgically induced in neonatal pigs on postnatal days 1, 2, 3, 7, and 14 (ie, the P1, P2, P3, P7, and P14 groups, respectively). Cardiac systolic function was evaluated before AMI and at 30 days post-AMI via transthoracic echocardiography. Cardiomyocyte cell cycle activity was assessed via immunostaining for proliferation and mitosis markers, infarct size was evaluated histologically, and telomerase activity was measured by quantitative polymerase chain reaction., Results: Systolic function at day 30 post-AMI was largely restored in P1 animals and partially restored in P2 animals, but significantly impaired when AMI was induced on postnatal day 3 or later. Hearts of P1 animals showed little evidence of scar formation or wall thinning on day 30 after AMI, with increased measures of cell-cycle activity seen 6 days after AMI (ie, postnatal day 7) compared with postnatal day 7 in noninfarcted hearts., Conclusions: The neonatal porcine heart is capable of regeneration after AMI during the first 2 days of life. This phenomenon is associated with induction of cardiomyocyte proliferation and is lost when cardiomyocytes exit the cell cycle shortly after birth.

Haplotype is the combination of a series of genetic mutations that coexist on a single chromosome, each of which has its own unique haplotypes. As a common data analysis method, the analysis of haplotype is effective for the localization of heterozygosis SNPs on single chromosome, the excavation of disease genes and the search of maladies treatments. It mainly includes indirect computational inferential method and direct experimental method. In this review we introduced various haplotype analysis methods and applications, especially two important ones: single-molecule dilution and contiguity-preserving transposition sequencing common technology. Meanwhile, further research prospects on haplotype sequencing were proposed.

The full cDNA of Mi-ace-3 encoding an acetylcholinesterase (AChE) in Meloidogyne incognita was cloned and characterized. Mi-ace-3 had an open reading frame of 1875 bp encoding 624 amino acid residues. Key residues essential to AChE structure and function were conserved. The deduced Mi-ACE-3 protein sequence had 72% amino acid similarity with that of Ditylenchus destructor Dd-AChE-3. Phylogenetic analyses using 41 AChEs from 24 species showed that Mi-ACE-3 formed a cluster with 4 other nematode AChEs. Our results revealed that the Mi-ace-3 cloned in this study, which is orthologous to Caenorhabditis elegans AChE, belongs to the nematode ACE-3/4 subgroup. There was a significant reduction in the number of galls in transgenic tobacco roots when Mi-ace-1, Mi-ace-2, and Mi-ace-3 were knocked down simultaneously, whereas little or no effect were observed when only one or two of these genes were knocked down. This is an indication that the functions of these three genes are redundant., (Copyright © 2017. Published by Elsevier Inc.)

Defensins are small cationic peptides that constitute the first line of defense against pathogens and are involved in immune regulation. In this study, their role in peripheral nerve regeneration was investigated. Rat sciatic nerves were transected and the two nerve stumps were bridged by a chitin conduit with a gap of 5mm between the stumps. The animals were injected intramuscularly with mutated rabbit neutrophil peptide 1 (defensin mNP-1), the positive control nerve growth factor (NGF) or the negative control saline, for 7 consecutive days after repair. After 6 weeks, the sciatic functional index (SFI), MNCV (motor nerve conductive velocity) and morphological parameters including myelinated fiber amounts, fiber diameter, axon diameter, myelin thickness and G-ratio were measured. Compared to the SFI of saline group, the NGF and mNP-1 groups had an increase of 18.3% and 18.8%, respectively. The numbers of myelinated fibers in the distal nerve of NGF and mNP-1 groups were 1.45- and 1.32-fold higher than in the saline group. The MNCVs of NGF and mNP-1 groups were 7.3 and 4.4 times of that of saline group. Fiber diameter, axon diameter, myelin thickness and G-ratio in the NGF and mNP-1 groups were also significantly higher than those of saline group. Our results demonstrate that, like NGF, the defensin mNP-1 can promote regeneration after a peripheral nerve cut., (Copyright © 2016. Published by Elsevier Ireland Ltd.)