Publications by authors named "Hao Dong"

322 Publications

Glyphosate exposure attenuates testosterone synthesis via NR1D1 inhibition of StAR expression in mouse Leydig cells.

Sci Total Environ 2021 Apr 25;785:147323. Epub 2021 Apr 25.

Northwest A&F University, Yangling 712100, Shaanxi, China; Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China. Electronic address:

Glyphosate is a broad-spectrum herbicide that impairs testosterone synthesis in mammals. Leydig cells (LCs), the primary producers of testosterone, demonstrate rhythmic expression of circadian clock genes both in vivo and in vitro. The nuclear receptor NR1D1 is an important clock component that constitutes the subsidiary transcriptional/translational loop in the circadian clock system. Nr1d1 deficiency resulted in diminished fertility in both male and female mice. However, whether NR1D1 is involved in the glyphosate-mediated inhibition of testosterone synthesis in LCs remains unclear. Here, the involvement of NR1D1 in glyphosate-mediated inhibition of testosterone synthesis was investigated both in vitro and in vivo. Glyphosate exposure of TM3 cells significantly increased Nr1d1 mRNA levels, but decreased Bmal1, Per2, StAR, Cyp11a1, and Cyp17a1 mRNA levels. Western blotting confirmed elevated NR1D1 and reduced StAR protein levels following glyphosate exposure. Glyphosate exposure also reduced testosterone production in TM3 cells. In primary LCs, glyphosate exposure also upregulated Nr1d1 mRNA levels and downregulated the mRNA levels of other clock genes (Bmal1 and Per2) and steroidogenic genes (StAR, Cyp17a1, Cyp11a1, and Hsd3b2), and inhibited testosterone synthesis. Moreover, glyphosate exposure significantly reduced the amplitude and shortened the period of PER2::LUCIFERASE oscillations in primary LCs isolated from mPer2 knock-in mice. Four weeks of oral glyphosate upregulated NR1D1 at both the mRNA and protein levels in mouse testes, and this was accompanied by a reduction in StAR expression. Notably, serum testosterone levels were also drastically reduced in mice treated with glyphosate. Moreover, dual-luciferase reporter and EMSA assays revealed that in TM3 cells NR1D1 inhibits the expression of StAR by binding to a canonical RORE element present within its promoter. Together, these data demonstrate that glyphosate perturbs testosterone synthesis via NR1D1 mediated inhibition of StAR expression in mouse LCs. These findings extend our understanding of how glyphosate impairs male fertility.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147323DOI Listing
April 2021

Stable isotopes verify geographical origin of Tibetan chicken.

Food Chem 2021 Apr 19;358:129893. Epub 2021 Apr 19.

Institute of Quality Standard & Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing 100081, China. Electronic address:

Due to the particularity of origin area, the yield and price of Tibetan chicken are different from those in the plain areas, which leads to chickens from the plains being disguised as Tibetan chickens. In present study, Tibetan chicken and chicken from other four provinces in plain areas were distinguished by stable isotopes and chemometric methods. The cross-validation rate was 97.6%. Secondly, correlation between mean δC, δN, δH and δO values in chicken samples and environmentalparameters was investigated. These indicators are closely related to geographical environment. δC and δN values were positively correlated with longitude (R = 0.955) and altitude (R = 0.796), respectively. δO and δH values were negatively correlated with latitude (R = 0.903) and altitude (R = 0.938), respectively. At last, we used stable isotopes to trace Tibetan chicken from the different area of Tibet. When four stable isotope ratios were combined, we can distinguish them.
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http://dx.doi.org/10.1016/j.foodchem.2021.129893DOI Listing
April 2021

Goose parvovirus and the protein NS1 induce apoptosis through the AIF-mitochondrial pathway in goose embryo fibroblasts.

Res Vet Sci 2021 Apr 22;137:68-76. Epub 2021 Apr 22.

College of Animal Science and Technology, Jilin Agricultural University, Changchun, Jilin Province 130118, China. Electronic address:

In this study, the effects of Goose parvovirus (GPV) infection as well as the possible role of NS1 protein on apoptosis induction in goose embryo fibroblast (GEF) cells were examined. Flow cytometry analysis and TUNEL assays revealed that GPV infection and NS1 transfection induced significant apoptosis in GEF cells compared to what was observed in mock-infected cells. Interestingly, the increase in the rate of apoptosis detected in GPV-infected GEFs was accompanied by an increased viral load in the cells. In addition, the apoptotic pathway was mediated by apoptosis-inducing factors (AIFs) and internal factors that influence the release of AIFs. The results indicated that the mitochondrial membrane potential was decreased, and AIF expression was increased in the nucleus (P < 0.01). Reactive oxygen species (ROS) increased gradually within 48 h (P < 0.001). Cathepsin D activities were also increased (P < 0.05). The results demonstrated that the AIF-mediated pathway is a new mitochondrial apoptotic pathway and that mitochondrial depolarization, ROS content, and cathepsin D activities are the key factors influencing apoptosis in GEF cells.
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http://dx.doi.org/10.1016/j.rvsc.2021.04.018DOI Listing
April 2021

Strengthening of Precast RC Frame to Mitigate Progressive Collapse by Externally Anchored Carbon Fiber Ropes.

Polymers (Basel) 2021 Apr 16;13(8). Epub 2021 Apr 16.

Department of Civil and Airport Engineering, Nanjing University of Aeronautics & Astronautics, Nanjing 211106, China.

The robustness of precast reinforced concrete (RC) frames is relatively poor, while the precast RC frames are strengthened to mitigate progressive collapse, avoiding "strong beams and weak columns" and the anchorage failure of strengthening materials under large deformation condition are the key problems. Aiming to discuss these problems, this paper carried out an experimental research of strengthening on three half-scale assembled monolithic frame subassemblages to mitigate progressive collapse. One specimen was strengthened by implanting carbon fiber rope (CFR) with polymer into concrete, one specimen was strengthened by binding CFR with special knot, and the last one was not strengthened. The failure mode, collapse failure mechanism and strengthening effect of subassemblages were discussed. Analytical models of load capacity increment contributed by CFR and construction suggestions of precast RC frame to mitigate progressive collapse were proposed. The results indicated that none of the strengthened specimens had anchorage failure. The two strengthening methods significantly increased the load capacity of the subassemblages in the catenary action (CA) stage with little effect on the flexural action (FA) stage and compressive arch action (CAA) stage.
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http://dx.doi.org/10.3390/polym13081306DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072533PMC
April 2021

Electroacupuncture Ameliorates Depressive-Like Behaviors in Poststroke Rats via Activating the tPA/BDNF/TrkB Pathway.

Neuropsychiatr Dis Treat 2021 13;17:1057-1067. Epub 2021 Apr 13.

Beijing Bo'ai Hospital, China Rehabilitation Research Center, China Rehabilitation Science Institute, Beijing, People's Republic of China.

Background: Electroacupuncture (EA) is a form of physical therapy that has been widely used in clinical practice in China. Post-stroke depression (PSD) is the most common neuropsychiatric complication after stroke. EA has been shown to have beneficial effects on PSD patients. However, the potential mechanism underlying the protective effects of EA on PSD remains unclear. Here, we investigated whether tissue plasminogen activator (tPA)/brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) signaling pathway participates in the therapeutic effects of EA in a rat PSD model.

Methods: Experimental PSD was induced by combining middle cerebral artery occlusion (MCAO) with chronic unpredictable mild stimulation (CUMS) in adult male rats. Bodyweight gain, neurological score, sucrose preference, and open field test were determined at 0, 7, 14, and 35 days after completing MCAO. The protein expressions of tPA, precursor BDNF (proBDNF), mature BDNF (mBDNF), and TrkB were measured by immunofluorescence and Western blot analysis. The tPA inhibitor plasminogen inhibitor-1 (PAI-1) was used to explore whether tPA plays a crucial role in the protective effects of EA on PSD.

Results: Compared with the sham rats, the PSD rats showed decreased bodyweight, deteriorated neurological score, and significant depressive-like behaviors. EA remarkably reversed bodyweight loss, neurological deficit, and depressive-like behaviors in PSD rats. Immunofluorescence staining and Western blot analysis showed that PSD-induced decreased expression of tPA, mBDNF, and TrkB were prevented by EA. Furthermore, we found that the effects of EA against PSD-induced depressive-like behaviors were abolished by PAI-1, the specific inhibitor of tPA.

Conclusion: Our results suggest that the improvement in depressive-like behaviors induced by EA is likely achieved via activation of the tPA/BDNF/TrkB pathway.
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http://dx.doi.org/10.2147/NDT.S298540DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8053498PMC
April 2021

Preparation of an Amidated Graphene Oxide/Sulfonated Poly Ether Ether Ketone (AGO/SPEEK) Modified Atmosphere Packaging for the Storage of Cherry Tomatoes.

Foods 2021 Mar 7;10(3). Epub 2021 Mar 7.

School of Food Science and Technology, South China University of Technology, 381, Wushan Rd., Tianhe District, Guangzhou 510641, China.

The shelf life of cherry tomatoes is short so that new and efficient preservation techniques or procedures are required to reduce postharvest losses. This study focused on the development of a sulfonated poly ether ether ketone (SPEEK) film incorporated with amidated graphene oxide (AGO), for the storage of cherry tomatoes in modified atmosphere packaging. The mechanical properties, gas permeability, and moisture permeability were subsequently tested. The evolution of attributes related to shelf life, such as gas composition, physicochemical properties, and sensory properties were also monitored during storage trials. AGO, as an inorganic filler, increases the thermal stability and mechanical properties of SPEEK-based films, while it reduces the water absorption, swelling rate, and moisture permeability. Importantly, all the AGO/SPEEK films exhibited enhanced gas permeability and selective permeability of CO/O relative to the SPEEK film. Moreover, 0.9% () AGO/SPEEK film showed an enhanced permeability coefficient of CO, corresponding to an increase of 50.7%. It could further improve the selective coefficient of CO/O to 67.1%. The results of preservation at 8 °C revealed that: 0.9% () AGO/SPEEK film was significantly effective at maintaining the quality and extending the shelf life of cherry tomatoes from 15 to 30 days, thereby suggesting the potential for applying AGO-incorporated SPEEK films for food packaging materials.
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http://dx.doi.org/10.3390/foods10030552DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8001178PMC
March 2021

Shape optimization of acoustic horns for improved directivity control and radiation efficiency based on the multimodal method.

J Acoust Soc Am 2021 Mar;149(3):1411

Key Laboratory of Modern Acoustics (Ministry of Education) and Institute of Acoustics, Nanjing University, Nanjing 210093, China.

The multimodal method is used to develop an approach for optimizing the shape of axisymmetric acoustic horns for both well-controlled directivity and high radiation efficiency over a wide frequency range. A horn with an arbitrary profile can be efficiently modeled with the multimodal method by projecting the wave field over transverse modes in connected short cylinders; the radii of the cylinders are used directly as design variables. Many design variables are employed in the optimization process to ensure design flexibility and computational accuracy. The relative weights for the design objectives of constant directivity, high radiation efficiency, and acceptable shape smoothness are adjusted by two coefficients in the objective function. The optimization problem is solved with a gradient-based algorithm, which takes advantage of algebraic gradient expressions. Numerical experiments demonstrate that the optimization procedure generates smooth horn contours that exhibit considerably improved performance over the target frequency band. Interestingly, a high-quality horn produced with moderate weight coefficients is similar in shape to constant-directivity horns invented earlier while having good low-frequency loading properties. The proposed method provides an attractive alternative to conventional horn design approaches.
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http://dx.doi.org/10.1121/10.0003568DOI Listing
March 2021

Development of polymorphic microsatellite markers for the Tertiary relict tree species Taiwania cryptomerioides (Cupressaceae) in East Asia.

Mol Biol Rep 2021 Mar 23;48(3):3031-3036. Epub 2021 Mar 23.

School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, China.

Taiwania cryptomerioides Hayata is an endangered relict tree species which is endemic to mainland China, Taiwan, Myanmar, and northern Vietnam. It is an economically important tree species and has been used for reforestation in mountain areas of mainland China and Taiwan. In order to investigate its genetic diversity for conservation and restoration, we developed and characterized 15 nuclear microsatellite markers based on next-generation sequencing data. A total of 100 microsatellite primer pairs were initially designed and tested based on the restriction-site associated DNA sequencing data. 60 of 100 loci (60%) were successfully amplified, of which 42 loci exhibited polymorphism. Fifteen polymorphic microsatellite loci with clear peaks were selected for further analyses in four T. cryptomerioides populations sampled from China (Hubei, Fujian, Guizhou, and Yunnan). The number of alleles per locus ranged from 2 to 24, and the levels of observed and expected heterozygosity ranged from 0.000 to 0.950 and from 0.000 to 0.860, respectively. This set of microsatellite markers will be useful for future population genetic studies of T. cryptomerioides in East Asia.
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http://dx.doi.org/10.1007/s11033-021-06287-zDOI Listing
March 2021

The Morphology of Hydroxyapatite Nanoparticles Regulates Cargo Recognition in Clathrin-Mediated Endocytosis.

Front Mol Biosci 2021 4;8:627015. Epub 2021 Mar 4.

Kuang Yaming Honors School, Nanjing University, Nanjing, China.

The clathrin-associated protein adaptin-2 (AP2) is a distinctive member of the hetero-tetrameric clathrin adaptor complex family. It plays a crucial role in many intracellular vesicle transport pathways. The hydroxyapatite (HAp) nanoparticles can enter cells through clathrin-dependent endocytosis, induce apoptosis, and ultimately inhibit tumor metastasis. Exploring the micro process of the binding of AP2 and HAp is of great significance for understanding the molecular mechanism of HAp's anti-cancer ability. In this work, we used molecular modeling to study the binding of spherical, rod-shaped, and needle-shaped HAps toward AP2 protein at the atomic level and found that different nanoparticles' morphology can determine their binding specificity through electrostatic interactions. Our results show that globular HAp significantly changes AP2 protein conformation, while needle-shaped HAP has more substantial binding energy with AP2. Therefore, this work offers a microscopic picture for cargo recognition in clathrin-mediated endocytosis, clarifies the design principles and possible mechanisms of high-efficiency nano-biomaterials, and provides a basis for their potential anti-tumor therapeutic effects.
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http://dx.doi.org/10.3389/fmolb.2021.627015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969717PMC
March 2021

EMBRYO SAC DEVELOPMENT 1 affects seed setting rate in rice by controlling embryo sac development.

Plant Physiol 2021 Mar 5. Epub 2021 Mar 5.

College of Agronomy, Hunan Agricultural University, Changsha 410128, China.

Seed setting rate is one of the critical factors that determine rice yield. Grain formation is a complex biological process, whose molecular mechanism is yet to be improved. Here we investigated the function of an OVATE family protein, Embryo Sac Development 1 (ESD1), in the regulation of seed setting rate in rice (Oryza sativa) by examining its loss-of-function mutants generated via clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated9 (Cas9) technology. ESD1 was predominantly expressed at Stage 6 of panicle development, especially in the ovules. esd1 mutants displayed reduced seed setting rates with normal stamen development and pollen tube growth but abnormal pistil group. Investigation of embryo sacs revealed that during the mitosis of functional megaspores, some egg cells degraded during differentiation in esd1 mutants, thereby hindering subsequent fertilization process and reducing seed setting rate. In addition, the transcriptional level of O. sativa anaphase-promoting complex 6, a reported embryo sac developing gene, was significantly reduced in esd1 mutants. These results support that ESD1 is an important modulator of ESD and seed setting rate in rice. Together, this finding demonstrates that ESD1 positively regulates the seed setting rate by controlling ESD in rice and has implications for the improvement of rice yield.
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http://dx.doi.org/10.1093/plphys/kiab106DOI Listing
March 2021

Sleep and circadian rhythm disturbances in intensive care unit (ICU)-acquired delirium: a case-control study.

J Int Med Res 2021 Mar;49(3):300060521990502

Department of Pulmonary and Critical Care Medicine, Binzhou Medical University Hospital, Binzhou, China.

Objective: The relationships among sleep, circadian rhythm, and intensive care unit (ICU)-acquired delirium are complex and remain unclear. This study aimed to examine the pathophysiological mechanisms of sleep and circadian rhythm disturbances in patients with ICU-acquired delirium.

Methods: This study included critical adult patients aged 18 to 75 years who were treated in the ICU. Twenty-four-hour polysomnography was performed and serum melatonin and cortisol levels were measured six times during polysomnography. Receiver operating characteristic curves and binomial logistic regression were used to evaluate the potential of sleep, melatonin, and cortisol as indicators of delirium in the ICU.

Results: Patients with delirium (n = 24) showed less rapid eye movement (REM) sleep compared with patients without delirium (n = 24, controls). Melatonin levels were lower and cortisol levels were higher in the delirium group than in the control group. REM sleep, melatonin, and cortisol were significantly associated with delirium. The optimal cutoff values of REM sleep and mean melatonin and cortisol levels that predicted delirium were ≤1.05%, ≤422.09 pg/mL, and ≥212.14 ng/mL, respectively.

Conclusions: REM sleep, and melatonin and cortisol levels are significantly associated with the risk of ICU-acquired delirium. Improved sleep and readjustment of circadian rhythmicity may be therapeutic targets of ICU-acquired delirium.
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http://dx.doi.org/10.1177/0300060521990502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7983249PMC
March 2021

Ultrasonic seed treatment improved morpho-physiological and yield traits and reduced grain Cd concentrations in rice.

Ecotoxicol Environ Saf 2021 May 11;214:112119. Epub 2021 Mar 11.

State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Agriculture, South China Agricultural University, Guangzhou 510642, China; Scientific Observing and Experimental Station of Crop Cultivation in South China, Ministry of Agriculture and Rural Affairs, Guangzhou 510642, China; Guangzhou Key Laboratory for Science and Technology of Fragrant Rice, Guangzhou 510642, China. Electronic address:

Rice cultivation under cadmium (Cd) contaminated soil often results in reduced growth with excess grain Cd concentrations. A pot experiment was conducted to assess the potential of ultrasonic seed treatment to alleviate Cd stress in rice. Seeds of two aromatic rice cultivars i.e., Xiangyaxiangzhan and Meixiangzhan 2 and two non-aromatic rice cultivars i.e., Huahang 31 and Guangyan 1 were exposed to ultrasonic waves for 1.5 min in 20-40 KHz mixing frequency. The experimental treatments were comprised of untreated seeds (U0) and ultrasonic treated seeds (U1) transplanted in un-contaminated soil (H0) and Cd-contaminated soil (H1). Results revealed that Cd contents and Cd accumulation in grain in U1 were 33.33-42.31% and 12.86-57.58% lower than U0 for fragrant rice cultivars under H1. Meanwhile, biomass production was higher in U1 than U0 under H0 and better yield was assessed in U1 for all cultivars under H1. The activity of peroxidase (POD) in flag leaves was increased by 8.28-115.65% for all cultivars while malondialdehyde (MDA) contents were significantly decreased in U1 compared with U0 under H0. Conclusively, ultrasonic treatment modulated Cd distribution and accumulation in different parts while improved physiological performance as well as yield and grain quality of rice under Cd contaminated conditions.
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http://dx.doi.org/10.1016/j.ecoenv.2021.112119DOI Listing
May 2021

Alterations in intestinal microbiota diversity, composition, and function in patients with sarcopenia.

Sci Rep 2021 Feb 25;11(1):4628. Epub 2021 Feb 25.

Department of Geriatrics, Peking Union Medical College Hospital, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China.

16S rRNA sequencing of human fecal samples has been tremendously successful in identifying microbiome changes associated with both aging and disease. A number of studies have described microbial alterations corresponding to physical frailty and nursing home residence among aging individuals. A gut-muscle axis through which the microbiome influences skeletal muscle growth/function has been hypothesized. However, the microbiome has yet to be examined in sarcopenia. Here, we collected fecal samples of 60 healthy controls (CON) and 27 sarcopenic (Case)/possibly sarcopenic (preCase) individuals and analyzed the intestinal microbiota using 16S rRNA sequencing. We observed an overall reduction in microbial diversity in Case and preCase samples. The genera Lachnospira, Fusicantenibacter, Roseburia, Eubacterium, and Lachnoclostridium-known butyrate producers-were significantly less abundant in Case and preCase subjects while Lactobacillus was more abundant. Functional pathways underrepresented in Case subjects included numerous transporters and phenylalanine, tyrosine, and tryptophan biosynthesis suggesting that protein processing and nutrient transport may be impaired. In contrast, lipopolysaccharide biosynthesis was overrepresented in Case and PreCase subjects suggesting that sarcopenia is associated with a pro-inflammatory metagenome. These analyses demonstrate structural and functional alterations in the intestinal microbiota that may contribute to loss of skeletal muscle mass and function in sarcopenia.
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http://dx.doi.org/10.1038/s41598-021-84031-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7907362PMC
February 2021

Engineering bioscaffolds for enzyme assembly.

Biotechnol Adv 2021 Feb 23:107721. Epub 2021 Feb 23.

Department of Bioproducts and Biosystems Engineering, University of Minnesota, St Paul, MN 55108, USA. Electronic address:

With the demand for green, safe, and continuous biocatalysis, bioscaffolds, compared with synthetic scaffolds, have become a desirable candidate for constructing enzyme assemblages because of their biocompatibility and regenerability. Biocompatibility makes bioscaffolds more suitable for safe and green production, especially in food processing, production of bioactive agents, and diagnosis. The regenerability can enable the engineered biocatalysts regenerate through simple self-proliferation without complex re-modification, which is attractive for continuous biocatalytic processes. In view of the unique biocompatibility and regenerability of bioscaffolds, they can be classified into non-living (polysaccharide, nucleic acid, and protein) and living (virus, bacteria, fungi, spore, and biofilm) bioscaffolds, which can fully satisfy these two unique properties, respectively. Enzymes assembled onto non-living bioscaffolds are based on single or complex components, while enzymes assembled onto living bioscaffolds are based on living bodies. In terms of their unique biocompatibility and regenerability, this review mainly covers the current advances in the research and application of non-living and living bioscaffolds with focus on engineering strategies for enzyme assembly. Finally, the future development of bioscaffolds for enzyme assembly is also discussed. Hopefully, this review will attract the interest of researchers in various fields and empower the development of biocatalysis, biomedicine, environmental remediation, therapy, and diagnosis.
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http://dx.doi.org/10.1016/j.biotechadv.2021.107721DOI Listing
February 2021

Long-Lasting Bioluminescence Imaging of the Fibroblast Activation Protein by an Amphiphilic Block Copolymer-Based Probe.

Anal Chem 2021 03 18;93(8):3726-3732. Epub 2021 Feb 18.

Hunan Provincial Key Laboratory of Cytochemistry, School of Chemistry and Food Engineering, Changsha University of Science and Technology, Changsha 410114, P. R. China.

Long-term specific tracing of the fibroblast activation protein (FAP) has been of great importance because it is heavily expressed by stromal fibroblasts of multiple diseases, and several disorders associated with FAP are chronical. Bioluminescence (BL) imaging has its advantages to detect FAP since no external excitation is required, but the current FAP-responsive BL probe was constructed by covalently masking the firefly luciferase substrate and easily secreted out from the animal, resulting in transient BL imaging of FAP. To circumvent this problem, a peptide-linked amphiphilic block copolymer-based probe (PABC) was developed and applied to the long-lasting BL image of FAP . For this purpose, an amphiphilic block copolymer containing an FAP-responsive peptide was fabricated to self-assemble into micelles, which act as a depot to load amounts of d-luciferin for constructing the BL probe. Upon reaction with FAP, the micelle would be destroyed to release the internal d-luciferin for BL emission by a luciferase-catalyzed reaction. By virtue of the high loading capability of micelles, the FAP was determined from 0.5 to 10 ng/mL with a detection limit of 0.105 ng/mL, and the high sensitivity makes the PABC capable of distinguishing cancer cells from normal ones. Importantly, compared with free d-luciferin, PABC can be used to persistently image the FAP in living cells and . This characteristic of long-lasting specific tracing of the FAP makes us envision that this BL probe could be used for screening of FAP inhibitors and diagnosing various FAP-related diseases in future.
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http://dx.doi.org/10.1021/acs.analchem.0c03638DOI Listing
March 2021

Orientation Switching of Single Molecules on Surface Excited by Tunneling Electrons and Ultrafast Laser Pulses.

J Phys Chem Lett 2021 Feb 18;12(7):2011-2016. Epub 2021 Feb 18.

Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

We investigate the orientation switching of individual azobenzene molecules adsorbed on a Au(111) surface using a laser-assisted scanning tunneling microscope (STM). It is found that the rotational motion of the molecule can be regulated by both sample bias and laser wavelength. By measuring the switching rate and state occupation as a function of both bias voltage and photon energy, the threshold in sample bias and the minimal photon energy are derived. It has been revealed that the tip-induced local electrostatic potential remarkably contributes to the reduction in hopping barrier. We also find that the tunneling electrons and photons play distinct roles in controlling rotational dynamics of single azobenzene molecules on the surface, which are useful for understanding dynamic behaviors in similar molecular systems.
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http://dx.doi.org/10.1021/acs.jpclett.0c03838DOI Listing
February 2021

Association of the Expression Levels of Long-Chain Noncoding RNA TUG1 and Its Gene Polymorphisms with Knee Osteoarthritis.

Genet Test Mol Biomarkers 2021 Feb;25(2):102-110

Department of Orthopedics, Chengdu First People's Hospital, Chengdu, China.

To study the association of the expression levels of long noncoding RNA Taurine-upregulated gene 1 (lncRNA TUG1) and TUG1 polymorphisms with knee osteoarthritis (KOA). A total of 255 KOA patients and 255 controls from May 2017 to December 2019 were selected for the study. Sanger sequencing was conducted to detect the genotypes of the TUG1 rs5749201, rs7284767, and rs886471 loci in all study subjects. Unconditional logistic regression analysis was used to calculate odds ratios and 95% confidence intervals, and the associations between the rs574901, rs7284767 and rs886471 loci and KOA risk were analyzed. Multifactor dimensionality reduction was used to analyze the interactions among alleles at the three loci examined. Quantitative real-time polymerase chain reaction was used to evaluate the expression levels of lncRNA in plasma. A total of 255 KOA patients and 255 control subjects completed the study. After adjusting for the factors of gender, age, body mass index, smoking history, drinking history, and family history, we found that the carriers of the A allele of the TUG1 rs5749201 locus were 1.36 times more likely to develop KOA than the carriers of the T allele (95% confidence interval [CI] = 1.05-1.75,  = 0.02); the G allele of the rs7284767 locus was a protective factor for KOA (odds ratio [OR] = 0.71, 95% CI = 0.54-0.92,  = 0.01); and the allelic variation at rs886471 G > T led to an increased risk of KOA by 2.34 times (95% CI = 1.53-3.57,  < 0.01). We also found that the GAG haplotype for the three loci was significantly associated with the increased risk of KOA (OR = 2.77, 95% CI = 1.67-4.57,  < 0.01). There was no correlation found between the TUG1 rs886471, rs5749201, and rs7284767 single nucleotide polymorphisms loci and the severity of KOA. The allelic variation at TUG1 rs5749201 T > A, rs886471 T > G were associated with decreased levels of lncRNA in the plasma of the subjects, while the allelic variation at rs7284767 A > G was associated with increased levels of lncRNA in plasma ( = 0.01,  < 0.01,  < 0.01). Plasma lncRNA levels and loci at the rs5749201, rs7284767, and rs886471 loci are associated with KOA risk.
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http://dx.doi.org/10.1089/gtmb.2020.0208DOI Listing
February 2021

Study on the Electrochemical Removal Mechanism of Oxytetracycline by a Ti/IrO-TaO Plate.

Int J Environ Res Public Health 2021 02 10;18(4). Epub 2021 Feb 10.

College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Ji'nan 250353, China.

In this study, a Ti/IrO-TaO anode was prepared by a hydrothermal method, and the prepared electrode was characterized by techniques such as scanning electron microscopy, X-ray diffraction, and electron dispersive spectroscopy. At the same time, the anode characteristics before and after electrochemical experiments were analyzed. The electrode gradation mechanism of oxytetracycline is discussed. In the whole experimental process, the range of electrolysis conditions was determined by single factor experiment, and then the optimal removal condition of oxytetracycline was determined by orthogonal experiments. The removal rate of oxytetracycline reached 99.02% after 20 min of electrolysis under the following optimal conditions: a current of 0.500 A, plate spacing of 2 cm, NaSO electrolyte concentration of 4 g/L, and solution pH of 3. Additionally, the mechanism of oxytetracycline removal was explored, free radical scavenging experiments were performed, and the degradation mechanism was inferred based on the changes in the ultraviolet absorption of the oxytetracycline solution before and after electrolysis. Then, based on the liquid chromatography-mass spectrometry data, seven possible compounds and five possible removal pathways were proposed.
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http://dx.doi.org/10.3390/ijerph18041708DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7916611PMC
February 2021

Chinese herbal medicine injections (CHMIs) for chronic pulmonary heart disease: A protocol for a Bayesian network meta-analysis.

Medicine (Baltimore) 2021 Jan;100(3):e24128

Department of Geriatrics, Liaocheng People's Hospital, Liaocheng, Shandong Province, PR China.

Background: Chinese herbal medicine injections (CHMIs) are frequently used for various refractory diseases including chronic pulmonary heart disease (CPHD). However, due to the diversity of CHMIs treatments, its relative effectiveness and safety remain unclear. In our study, Bayesian network meta-analysis will be used to identify differences in efficacy and safety between diverse CHMI for CPHD.

Methods: Relevant randomized controlled trials (RCTs) and prospective controlled clinical trials published in PubMed, Google Scholar, Excerpt Medica Database, Medline, Cochrane Library, Web of Science, China Scientific Journal Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database and Wanfang Database will be systematic searched to identify eligible studies from their establishment to December 2020. The methodological qualities, including the risk of bias, will be evaluated using the Cochrane risk of bias assessment tool. Stata14.2 and WinBUGS 1.4.3 software were used for data synthesis. The evidentiary grade of the results will be also evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

Results: The results of this study will be published in a peer-reviewed journal, and provide reliable evidence for different CHMIs on CPHD.

Conclusions: The findings will provide reference for evaluating the efficacy and safety of different CHMIs for CPHD, and provide a helpful evidence for clinicians to formulate the best adjuvant treatment strategy for CPHD patients.

Trial Registration Number: INPLASY2020120004.
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http://dx.doi.org/10.1097/MD.0000000000024128DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7837975PMC
January 2021

Lanthanide-Doped Upconversion Nanoparticles for Super-Resolution Microscopy.

Front Chem 2020 15;8:619377. Epub 2021 Jan 15.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.

Super-resolution microscopy offers a non-invasive and real-time tool for probing the subcellular structures and activities on nanometer precision. Exploring adequate luminescent probes is a great concern for acquiring higher-resolution image. Benefiting from the atomic-like transitions among real energy levels, lanthanide-doped upconversion nanoparticles are featured by unique optical properties including excellent photostability, large anti-Stokes shifts, multicolor narrowband emissions, tunable emission lifetimes, etc. The past few years have witnessed the development of upconversion nanoparticles as probes for super-resolution imaging studies. To date, the optimal resolution reached 28 nm (λ/36) for single nanoparticles and 82 nm (λ/12) for cytoskeleton structures with upconversion nanoparticles. Compared with conventional probes such as organic dyes and quantum dots, upconversion nanoparticle-related super-resolution microscopy is still in the preliminary stage, and both opportunities and challenges exist. In this perspective article, we summarized the recent advances of upconversion nanoparticles for super-resolution microscopy and projected the future directions of this emerging field. This perspective article should be enlightening for designing efficient upconversion nanoprobes for super-resolution imaging and promote the development of upconversion nanoprobes for cell biology applications.
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http://dx.doi.org/10.3389/fchem.2020.619377DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7843451PMC
January 2021

Desilylation Induced by Metal Fluoride Nanocrystals Enables Cleavage Chemistry In Vivo.

J Am Chem Soc 2021 Feb 31;143(5):2250-2255. Epub 2021 Jan 31.

Beijing National Laboratory for Molecular Sciences, Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.

Metal fluoride nanocrystals are widely used in biomedical studies owing to their unique physicochemical properties. The release of metal ions and fluorides from nanocrystals is intrinsic due to the solubility equilibrium. It used to be considered as a drawback because it is related to the decomposition and defunction of metal fluoride nanocrystals. Many strategies have been developed to stabilize the nanocrystals, and the equilibrium concentrations of fluoride are often <1 mM. Here we make good use of this minimum amount of fluoride and unveil that metal fluoride nanocrystals could effectively induce desilylation cleavage chemistry, enabling controlled release of fluorophores and drug molecules in test tubes, living cells, and tumor-bearing mice. Biocompatible PEG (polyethylene glycol)-coated CaF nanocrystals have been prepared to assay the efficiency of desilylation-induced controlled release of functional molecules. We apply the strategy to a prodrug activation of monomethyl auristatin E (MMAE), showing a remarkable anticancer effect, while side effects are almost negligible. In conclusion, this desilylation-induced cleavage chemistry avails the drawback on empowering metal fluoride nanocrystals with a new function of perturbing or activating for further biological applications.
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http://dx.doi.org/10.1021/jacs.0c10399DOI Listing
February 2021

Binding Peptide-Guided Immobilization of Lipases with Significantly Improved Catalytic Performance Using BL21(DE3) Biofilms as a Platform.

ACS Appl Mater Interfaces 2021 Feb 27;13(5):6168-6179. Epub 2021 Jan 27.

Department of Bioproducts and Biosystems Engineering, University of Minnesota, St Paul, Minnesota 55108, USA.

Developing novel immobilization methods to maximize the catalytic performance of enzymes has been a permanent pursuit of scientific researchers. Engineered biofilms have attracted great concern as surface display platforms for enzyme immobilization. However, current biological conjugation methods, such as the SpyTag/SpyCatcher tagging pair, that immobilize enzymes onto biofilms seriously hamper enzymatic performance. Through phage display screening of lipase-binding peptides (LBPs) and co-expression of CsgB (nucleation protein of curli nanofibers) and LBP2-modified CsgA (CsgALBP2, major structural subunit of curli nanofibers) proteins, we developed BL21::ΔCsgA-CsgB-CsgALBP2 (LBP2-functionalized) biofilms as surface display platforms to maximize the catalytic performance of lipase (Lip181). After immobilization onto LBP2-functionalized biofilm materials, Lip181 showed increased thermostability, pH, and storage stability. Surprisingly, the relative activity of immobilized Lip181 increased from 8.43 to 11.33 U/mg through this immobilization strategy. Furthermore, the highest loading of lipase on LBP2-functionalized biofilm materials reached up to 27.90 mg/g of wet biofilm materials, equivalent to 210.49 mg/g of dry biofilm materials, revealing their potential as a surface with high enzyme loading capacity. Additionally, immobilized Lip181 was used to hydrolyze phthalic acid esters, and the hydrolysis rate against dibutyl phthalate was up to 100%. Thus, LBP2-mediated immobilization of lipases was demonstrated to be far more advantageous than the traditional SpyTag/SpyCatcher strategy in maximizing enzymatic performance, thereby providing a better alternative for enzyme immobilization onto biofilms.
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http://dx.doi.org/10.1021/acsami.0c18298DOI Listing
February 2021

Manganese supported on controlled dealumination Y-zeolite for ozone catalytic oxidation of low concentration toluene at low temperature.

Chemosphere 2021 May 9;271:129604. Epub 2021 Jan 9.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing, 210023, China; Quanzhou Institute for Environmental Protection Industry, Nanjing University, Beifeng Road, Quanzhou, 362000, China. Electronic address:

Low-temperature catalytic degradation of VOCs with ozone has received widespread attention recently. In this work, a combination method of steam and nitric acid was used to control the dealuminization of Y zeolite, and then manganese oxide was loaded on the Y zeolite by impregnation method. It was found that MnO was highly dispersed in the dealumination zeolite, and the adsorbed oxygens were more easily activated in the active oxygen vacancies. The MnO supported on dealumination Y zeolite showed better catalytic effect than that supported on the parent Y. At low humidity (0.8%) in 30 °C, the degradation efficiency of toluene reached above 94% by using the catalyst with mild dealumination. When more water vapor was introduced, the degradation of toluene was inhibited. However, the catalytic performance of the catalyst with deep dealumination was not affected. With the help of in-situ DRIFTS, it was observed that the intermediates and reaction by-products had changed under different humidity conditions.
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http://dx.doi.org/10.1016/j.chemosphere.2021.129604DOI Listing
May 2021

Gating and regulation of the calcium release-activated calcium channel: Recent progress from experiments and molecular modeling.

Authors:
Jun Huo Hao Dong

Biopolymers 2020 Oct 10;111(10):e23392. Epub 2020 Sep 10.

Kuang Yaming Honors School, Nanjing University, Nanjing, China.

Calcium release-activated calcium (CRAC) channels are highly calcium ion (Ca)-selective channels in the plasma membrane. The transient drop of endoplasmic reticulum Ca level activates its calcium sensor stromal interaction molecule (STIM) and then triggers the gating of the CRAC channel pore unit Orai. This process involves a variety of activities of the immune system. Therefore, understanding how the activation and regulation of the CRAC channel can be accomplished is essential. Here we briefly summarize the recent progress on Orai gating and its regulation by 2-aminoethoxydiphenylborate (2-APB) obtained from structural biology studies, biochemical and electrophysiological measurements, as well as molecular modeling. Indeed, integration between experiments and computations has further deepened our understanding of the channel gating and regulation.
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http://dx.doi.org/10.1002/bip.23392DOI Listing
October 2020

Ablation efficiency of a novel Thulium fiber laser: an in vitro study on laser setting and fiber usage.

J Endourol 2021 Jan 6. Epub 2021 Jan 6.

Changhai Hospital, 12520, Urology, Shanghai, Shanghai, China;

Introduction: To investigate the ablation efficiency of Super-pulse Thulium fiber laser (SPTFL) with different laser setting and fiber usage.

Materials And Methods: SPTFL machine was attached with different fibers. Artificial stones were fixed in water, while laser fiber was driven on a platform for ablation. Pulse energy, frequency, fiber moving speed, fiber-to-stone distance and fiber size were adjusted in each trial. The cross-sectional area of craters on the lateral stone surface was measured for comparison of ablation rate, combined with fiber moving speed.

Results: There was a trend that the ablation rate increased as pulse energy or frequency increased. When pulse energy was set as 0.2 J and frequency was increased from 50 HZ to 150 HZ, the cross-sectional area of the crater was enlarged from 0.21 mm2 to 0.37 mm2 (p < 0.05); when the frequency was set as 100 HZ and pulse energy was increased from 0.1 J to 0.3 J, the crater was enlarged from 0.10 mm2 to 0.45 mm2 (p < 0.05). Furthermore, energy demonstrated greater impact on ablation rate and the crater was enlarged from 0.20 mm2 in 0.1 J × 300 HZ group to 0.44 mm2 in 0.3 J × 100 HZ group (p < 0.05). Then fiber was set at different moving speed with the same laser setting, the ablation rate of 3 mm/s group was 3.64 times higher than 0.5 mm/s group (p < 0.05). Ablation diminished as fiber-to-stone distance grew up. 200 μm fiber produced thinner and deeper fissure than 272 µm and 550 µm fiber, and the ablation rate was the highest for 200 μm fiber.

Conclusion: Pulse energy is a more important factor in influencing ablation efficiency compared with frequency. Closer fiber-to-stone distance, faster fiber movement and smaller fiber size increase ablation efficiency.
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http://dx.doi.org/10.1089/end.2020.1116DOI Listing
January 2021

Structures and Spectroscopic Properties of Large Molecules and Condensed-Phase Systems Predicted by Generalized Energy-Based Fragmentation Approach.

Acc Chem Res 2021 Jan 22;54(1):169-181. Epub 2020 Dec 22.

Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.

ConspectusThe structures and spectroscopic properties of molecules and condensed-phase systems are usually experimentally characterized by X-ray, infrared (IR), Raman, nuclear magnetic resonance (NMR), and electronic absorption/emission spectra. Quantum mechanics (QM) calculations are critical in quantitatively understanding the relationship between the structure and physicochemical properties of various chemical systems. However, it is very challenging to apply traditional QM methods to large molecules and condensed-phase systems with large unit cells due to their steep computational scaling with the system size. To overcome this difficulty, theoretical chemists have developed various linear (or low) scaling QM methods, among which energy-based fragmentation methods have achieved great success for large molecules or clusters. One of the most popular energy-based fragmentation methods is the generalized energy-based fragmentation (GEBF) approach developed by us.In this approach, the ground-state energy of a large molecule can be evaluated from the ground-state energies of a series of embedded subsystems. In this Account, we focus on the recent developments and applicability of the GEBF approach for the structures and spectroscopic properties of complicated large molecules and condensed-phase systems. With new fragmentation schemes, the GEBF approach can now describe ionic liquid clusters and metal-containing supramolecular systems accurately and can provide accurate binding energies for host-guest complexes. In addition, the GEBF approach is now available for describing the localized excited states of large systems including a chromophore. More importantly, the GEBF approach under periodic boundary conditions (PBC-GEBF) has been developed to deal with periodic molecular crystals and liquids. Then, the ground-state energy (or property) per unit cell of a periodic condensed phase system can be predicted with QM calculations on nonperiodic embedded subsystems. This feature enables accurate electron correlation calculations on molecular crystals and liquids to be feasible on ordinary workstations. The PBC-GEBF approach has been applied to predict the crystal structures, lattice energies, and spectroscopic properties of some typical molecular crystals and solutions. By combining the GEBF method and machine learning (ML) method, a GEBF-ML force field has been developed for long normal alkanes, and the IR spectra of long alkanes can be obtained from the GEBF-ML molecular dynamics (MD) simulations. The GEBF and its periodic variant are expected to play increasingly important roles in investigating real-life chemical systems of broad interests at the levels.
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http://dx.doi.org/10.1021/acs.accounts.0c00580DOI Listing
January 2021

Using Deep Learning to Detect Defects in Manufacturing: A Comprehensive Survey and Current Challenges.

Materials (Basel) 2020 Dec 16;13(24). Epub 2020 Dec 16.

Key Laboratory of Advanced Manufacturing Technology of Ministry of Education, Guizhou University, Guiyang 550025, China.

The detection of product defects is essential in quality control in manufacturing. This study surveys stateoftheart deep-learning methods in defect detection. First, we classify the defects of products, such as electronic components, pipes, welded parts, and textile materials, into categories. Second, recent mainstream techniques and deep-learning methods for defects are reviewed with their characteristics, strengths, and shortcomings described. Third, we summarize and analyze the application of ultrasonic testing, filtering, deep learning, machine vision, and other technologies used for defect detection, by focusing on three aspects, namely method and experimental results. To further understand the difficulties in the field of defect detection, we investigate the functions and characteristics of existing equipment used for defect detection. The core ideas and codes of studies related to high precision, high positioning, rapid detection, small object, complex background, occluded object detection and object association, are summarized. Lastly, we outline the current achievements and limitations of the existing methods, along with the current research challenges, to assist the research community on defect detection in setting a further agenda for future studies.
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http://dx.doi.org/10.3390/ma13245755DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7766692PMC
December 2020

Potential carcinogenic heterocyclic aromatic amines (HAAs) in foodstuffs: Formation, extraction, analytical methods, and mitigation strategies.

Compr Rev Food Sci Food Saf 2020 03 22;19(2):365-404. Epub 2020 Jan 22.

College of Light Industry and Food Sciences, Zhongkai University of Agriculture and Engineering, Guangzhou, China.

During the heat treatment of proteinaceous food, heterocyclic aromatic amines (HAAs), a kind of strong mutagens/carcinogens are formed. HAAs can be classified into two major groups based on the heating temperature, which are thermic HAAs generally formed in 150 to 300 °C and pyrolytic HAAs produced above 300 °C. This review focuses on the formation mechanisms of HAAs and identifies different mechanisms of the formation of HAAs in foodstuffs. Moreover, an overview of the available extraction, purification methods, and instrumental analytical methods in the last two decades is shown to determine the HAAs in various foodstuffs. Finally, based on the factors that affect the formation of HAAs in heat-processed foodstuffs, such as the cooking method, food type, the recipe, and the content of substances with enhancing or inhibiting effects on the formation of HAAs, this review also highlights the most promising strategies for mitigating HAAs, which include adjusting cooking methods or process conditions, adding natural product extracts, antioxidants or other compounds, or reasonable selection of types of foodstuff. The review intends to provide a broad but comprehensive understanding of the formation, extraction, purification, analytical methods, and possible mitigation strategies for isolated and identified HAAs.
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http://dx.doi.org/10.1111/1541-4337.12527DOI Listing
March 2020

Stable and Efficient Agrobacterium-Mediated Genetic Transformation of Larch Using Embryogenic Callus.

Front Plant Sci 2020 25;11:584492. Epub 2020 Nov 25.

State Key laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China.

or larch is an economically important coniferous tree species with rapid growth in the early stages, strong adaptability, and a short time to harvest. The genetic improvement of larch has garnered considerable attention in recent years for reclaiming timber forests. However, traditional breeding methods are largely ineffective for achieving rapid genetic improvement of . Studies show that the efficiency of plant regeneration can be improved by optimizing somatic embryogenesis. On this basis, we devised a stable, fast and efficient -mediated genetic transformation method using suspended embryogenic calluses as explants and β-glucuronidase as the reporter. We evaluated the effects of the load, co-culture period, and addition of acetosyringone and transformant screening antibiotic on the transformation efficiency. In addition, we tested the pCAMBIA 1300-HCA 2-1 promoter-GUS binary expression vector, which contains the GUS gene ORF under the control of high cambial activity HCA 2-1 promoter, and observed the tissue-specific expression of the GUS gene in the somatic embryos of transgenic larch. This novel technique can not only accelerate the generation of superior transgenic strains of but also aid in future gene functional studies.
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http://dx.doi.org/10.3389/fpls.2020.584492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723890PMC
November 2020