Publications by authors named "Feng Chen"

3,560 Publications

  • Page 1 of 1

A Deep-Learning Model With the Attention Mechanism Could Rigorously Predict Survivals in Neuroblastoma.

Front Oncol 2021 14;11:653863. Epub 2021 Jul 14.

Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Background: Neuroblastoma is one of the most devastating forms of childhood cancer. Despite large amounts of attempts in precise survival prediction in neuroblastoma, the prediction efficacy remains to be improved.

Methods: Here, we applied a deep-learning (DL) model with the attention mechanism to predict survivals in neuroblastoma. We utilized 2 groups of features separated from 172 genes, to train 2 deep neural networks and combined them by the attention mechanism.

Results: This classifier could accurately predict survivals, with areas under the curve of receiver operating characteristic (ROC) curves and time-dependent ROC reaching 0.968 and 0.974 in the training set respectively. The accuracy of the model was further confirmed in a validation cohort. Importantly, the two feature groups were mapped to two groups of patients, which were prognostic in Kaplan-Meier curves. Biological analyses showed that they exhibited diverse molecular backgrounds which could be linked to the prognosis of the patients.

Conclusions: In this study, we applied artificial intelligence methods to improve the accuracy of neuroblastoma survival prediction based on gene expression and provide explanations for better understanding of the molecular mechanisms underlying neuroblastoma.
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http://dx.doi.org/10.3389/fonc.2021.653863DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8317851PMC
July 2021

Targeting Tristetraprolin Expression or Functional Activity Regulates Inflammatory Response Induced by MSU Crystals.

Front Immunol 2021 16;12:675534. Epub 2021 Jul 16.

Institute of Rheumatology and Immunology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.

The RNA-binding protein tristetraprolin (TTP) is an anti-inflammatory factor that prompts the mRNA decay of target mRNAs and is involved in inflammatory diseases such as rheumatoid arthritis (RA). TTP is regulated by phosphorylation, and protein phosphatase 2A (PP2A) can dephosphorylate TTP to activate its mRNA-degrading function. Some small molecules can enhance PP2A activation. Short interfering RNA (siRNA) targeting TTP expression or PP2A agonist (Arctigenin) was administered to monosodium urate (MSU) crystal-induced J774A.1 cells, and the expression of inflammatory related genes was detected by RT-PCR and Western blot assays. The effects of Arctigenin in mouse models of acute inflammation induced by MSU crystals, including peritonitis and arthritis, were evaluated. The data indicated that TTP expression levels and endogenous PP2A activity were increased in MSU-crystal treated J774A.1 cells. TTP knockdown exacerbated inflammation-related genes expression and NLRP3 inflammasome activation. However, PP2A agonist treatment (Arctigenin) suppressed MSU crystal-induced inflammation in J774A.1 cells. Arctigenin also relieved mitochondrial reactive oxygen species (mtROS) production and improved lysosomal membrane permeability in MSU crystal-treated J774A.1 cells. Moreover, TTP knockdown reversed the anti-inflammatory and antioxidant effects of Arctigenin. Oral administration of Arctigenin significantly alleviated foot pad swelling, the number of inflammatory cells in peritoneal lavage fluids and the production of IL-1β in the mouse model of inflammation induced by MSU crystals. Collectively, these data imply that targeting TTP expression or functional activity may provide a potential therapeutic strategy for inflammation caused by MSU crystals.
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http://dx.doi.org/10.3389/fimmu.2021.675534DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8322984PMC
July 2021

The Efficacy and Safety of Acupuncture for Prophylaxis of Vestibular Migraine: A Study Protocol for a Randomized Controlled Trial.

Front Neurol 2021 15;12:709803. Epub 2021 Jul 15.

Department of Neurology, The First Affiliated Hospital of Jiaxing University, Jiaxing, China.

With a high incidence rate and low diagnosis rate, vestibular migraine (VM) can seriously affect the quality of life of patients, but it remains difficult to manage by current treatment options. Acupuncture may be a potential treatment option for VM prophylaxis, but the currently available evidence is still uncertain. Therefore, this trial aims to evaluate the efficacy and safety of acupuncture for VM prophylaxis. This is a 28-week parallel, randomized, controlled clinical trial including 4 weeks of baseline, 8 weeks of treatment, and 16 weeks of follow-up. A total of 72 participants will be randomly assigned to two groups. The participants will receive acupuncture in the experimental group, while the participants in the control group will be treated with venlafaxine. The primary outcome measures are change in vertigo/migraine days and vertigo/migraine attacks, vertigo severity, and migraine intensity per 4 weeks from baseline. The secondary outcome measures are change in doses of rescue medication, anxiety level, depression level, and quality of life per 4 weeks from baseline. Adverse events will be recorded for safety evaluation. This study will investigate the efficacy and safety of acupuncture for VM prophylaxis. The results will contribute to determining whether acupuncture can serve as an optional treatment strategy for treating VM. www.ClinicalTrials.gov, identifier: NCT0464088.
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http://dx.doi.org/10.3389/fneur.2021.709803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8319494PMC
July 2021

MicroRNA-670-3p suppresses ferroptosis of human glioblastoma cells through targeting ACSL4.

Free Radic Res 2021 Jul 29:1-22. Epub 2021 Jul 29.

Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan 430071, China.

Glioblastoma is one ofthe most frequent malignant tumors derived from the brain in adults with very poor prognosis. Ferroptosis is implicated in the initiation and progression of various tumors, includingtheglioblastoma. The present study aims to investigate the function of microRNA (miR)-670-3p in glioblastoma, and tries to demonstrate whether ferroptosis is involved in this process.Human glioblastoma cell lines, U87MG and A172, were transfected with the inhibitor, mimic and matched negative controlsof miR-670-3p to manipulate intracellular miR-670-3p level. To validate the involvement of ferroptosis in miR-670-3p inhibitor-mediated tumor suppressive effects, ferrostain-1 and liproxstatin-1 were used to inhibit ferroptosis in the presence of miR-670-3p inhibitor. In addition, the small interfering RNA against acyl-CoA synthase long chain family member 4 (ACSL4)was used to knock down endogenous ACSL4 expression. To validate thecombined effects between miR-670-3p inhibitor and temozolomide (TMZ), cells were pre-treated with TMZ and then transfected with or without miR-670-3p inhibitor.miR-670-3p level was elevated in human glioblastoma, but decreased upon ferroptotic stimulation. miR-670-3p inhibitor suppressed, while miR-670-3p mimic promotedglioblastoma cell growth through modulating ferroptosis. Mechanistically, ACSL4 was required for the regulation on ferroptosis andgrowth ofglioblastoma cells by miR-670-3p. Moreover, U87MG and A172 cells treated with miR-670-3p inhibitor showed an increased chemosensitivity to TMZ.We prove that miR-670-3p suppresses ferroptosis of human glioblastoma cells through targeting ACSL4, and that inhibiting miR-670-3p can be an alternative, at least adjuvant strategy to treat glioblastoma.
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http://dx.doi.org/10.1080/10715762.2021.1962009DOI Listing
July 2021

Allogeneic hematopoietic stem cell transplantation from nonsibling 10/10 HLA-matched related donors: a single-center experience.

Haematologica 2021 Jul 29. Epub 2021 Jul 29.

National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, China; Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China; Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, Suzhou, China; State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou.

Not available.
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http://dx.doi.org/10.3324/haematol.2021.278933DOI Listing
July 2021

Illuminating key microbial players and metabolic processes involved in the remineralization of particulate organic carbon in the ocean's twilight zone by metaproteomics.

Appl Environ Microbiol 2021 Jul 28:AEM0098621. Epub 2021 Jul 28.

State Key Laboratory of Marine Environmental Science/College of the Environment and Ecology, Xiamen University, Xiamen 361005, China.

The twilight zone (from the base of the euphotic zone to the depth of 1000 m) is the major area of particulate organic carbon (POC) remineralization in the ocean, and heterotrophic microbes contribute to more than 70% of the estimated remineralization. However, little is known about the microbial community and metabolic activity directly associated with POC remineralization in this chronically understudied realm. Here, we characterized the microbial community proteomes of POCs collected from the twilight zone of three contrasting sites in the Northwest Pacific Ocean using a metaproteomic approach. The particle-attached bacteria from Alteromonadales, Rhodobacterales, and Enterobacteriales were the primary POC remineralizers. Hydrolytic enzymes, including proteases and hydrolases, that degrade proteinaceous components and polysaccharides, the main constituents of POC, were abundant and taxonomically associated with these bacterial groups. Furthermore, identification of diverse species-specific transporters and metabolic enzymes implied niche specialization for nutrient acquisition among these bacterial groups. Temperature was the main environmental factor driven the active bacterial groups and metabolic processes, and Enterobacteriales replaced Alteromonadales as the predominant group under low temperature. This study provides insight into the key bacteria and metabolic processes involved in POC remineralization, and niche complementarity and species substitution among bacterial groups are critical for efficient POC remineralization in the twilight zone. The Ocean's twilight zone is a critical zone where more than 70% of the sinking particulate organic carbon (POC) are remineralized. Therefore, the twilight zone determines the size of biological carbon storage in the ocean, and regulates the global climate. Prokaryotes are major players that govern remineralization of POC in this region. However, knowledge of microbial community structure and metabolic activity is still lacking. This study unveiled microbial communities and metabolic activities of POCs collected from the twilight zone of three contrasting environments in the Northwest Pacific Ocean using a metaproteomic approach. Alteromonadales, Rhodobacterales and Enterobacteriales were the major remineralizers of POC. They excreted diverse species-specific hydrolytic enzymes to split POC to solubilized POC or dissolved organic carbon. Temperature played a crucial role in regulating the community composition and metabolism. Furthermore, niche complementarity or species substitution among bacterial groups guaranteed the efficient remineralization of POC in the twilight zone.
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http://dx.doi.org/10.1128/AEM.00986-21DOI Listing
July 2021

miR-30a-5p Regulates Viability, Migration, and Invasion of Lung Adenocarcinoma Cells via Targeting ECT2.

Comput Math Methods Med 2021 7;2021:6241469. Epub 2021 Jul 7.

Department of Respiratory Medicine, Taizhou Municipal Hospital, Taizhou 318000, China.

Objective: The abnormal expression of epithelial cell transforming sequence 2 (ECT2) is often considered the driving factor for the growth and invasion of tumors. This study was performed to investigate the regulatory effect of miR-30a-5p and ECT2 on lung adenocarcinoma (LUAD), which provides a basis for the effective clinical treatment of LUAD.

Methods: The mature miRNAs, expression data of mRNAs, and clinical data of LUAD were downloaded from The Cancer Genome Atlas (TCGA). The expression levels of ECT2 mRNA and miR-30a-5p in cancer cell lines were detected by qRT-PCR. Western blot was performed to test the expression of ECT2 protein. The targeting relationship between miR-30a-5p and ECT2 was verified by dual-luciferase assay. The CCK-8 method and Transwell assay were conducted to test the viability, migratory, and invasive abilities of cells.

Results: ECT2 expression was upregulated in LUAD and was significantly correlated with the LUAD clinical stage and pathologic T stage, and the expression of its upstream regulatory gene miR-30a-5p was downregulated. miR-30a-5p targeted ECT2 in LUAD. Downregulation of ECT2 could inhibit the viability, migration, and invasion of LUAD cells, which could be reversed by simultaneously suppressing the expression of miR-30a-5p.

Conclusion: Our results suggested that miR-30a-5p repressed the malignant progression of LUAD via downregulating ECT2. miR-30a-5p and ECT2 may be effective targets for LUAD patients.
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http://dx.doi.org/10.1155/2021/6241469DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279846PMC
July 2021

Bioorthogonal Chemical Signature Enabling Amplified Visualization of Cellular Oxidative Thymines.

Anal Chem 2021 Jul 22. Epub 2021 Jul 22.

Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xianning West Road, Xi'an 710049, Shaanxi, P. R. China.

Cellular oxidative thymines, 5-hydroxymethyluracil (5hmU) and 5-formyluracil (5fU), are found in the genomes of a diverse range of organisms, the distribution of which profoundly influence biological processes and living systems. However, the distribution of cellular oxidative thymines has not been explored because of lacking both specific bioorthogonal labeling and sensitivity methods for single-cell analysis. Herein, we report a bioorthogonal chemical signature enabling amplified visualization of cellular oxidative thymines in single cells. The synthesized ATP-γ-alkyne, an ATP analogue with bioorthogonal tag modified on γ-phosphate can be specifically linked to cellular 5hmU by chemoenzymatic labeling. DNA with 5-alkynephosphomethyluracil were then clicked with azide (N)-modified 5hmU-primer. Identification of 5fU is based on selective reduction from 5fU to 5hmU, subsequent chemoenzymatic labeling of the newly generated 5hmU, and cross-linking with N-modified 5fU-primer via click chemistry. Then, all of the 5hmU and 5fU sites are encoded with respective circularized barcodes. These barcodes are simultaneously amplified for multiplexed single-molecule imaging. The above two kinds of barcodes can be simultaneously amplified for differentiated visualization of 5hmU and 5fU in single cells. We find these two kinds of cellular oxidative thymines are spatially organized in a cell-type-dependent style with cell-to-cell heterogeneity. We also investigate their multilevel subcellular information and explore their dynamic changes during cell cycles. Further, using DNA sequencing instead of fluorescence imaging, our proposed bioorthogonal chemical signature holds great potential to offer the sequence information of these oxidative thymines in cells and may provide a reliable chemical biology approach for studying the whole-genome oxidative thymines profiles and insights into their functional role and dynamics in biology.
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http://dx.doi.org/10.1021/acs.analchem.1c01285DOI Listing
July 2021

A lacto-ovo-vegetarian dietary pattern is protective against sarcopenic obesity: A cross-sectional study of elderly Chinese people.

Nutrition 2021 Jun 7;91-92:111386. Epub 2021 Jun 7.

Department of Gerontology and Geriatrics, Shengjing Hospital of China Medical University. Electronic address:

Objectives: The purpose of this study was to investigate the correlation between dietary patterns and the risk of sarcopenic obesity (SO) in community-dwelling elderly people.

Methods: SO was defined as the coexistence of sarcopenia and obesity. Participants with low skeletal muscle index, low muscle strength, or low physical performance were diagnosed with sarcopenia, whereas obesity was defined as waist circumference ≥85 cm in men and ≥80 cm in women. Dietary patterns were determined by principal component analysis. Multinomial logistic regression analysis was used to evaluate the relationship between dietary patterns and SO.

Results: Among 3795 Chinese participants, 112 (3.0%) were diagnosed with SO. After adjustment for confounding variables, lacto-ovo-vegetarian dietary pattern was negatively associated with risk of SO. The odds ratio for SO was 0.79 (95% confidence interval, 0.65-0.97; P = 0.027) for the lacto-ovo-vegetarian dietary pattern, whereas meat-fish and junk food dietary patterns were not associated with the risk of SO.

Conclusions: We suggest that older people should have a balanced daily diet such as a lacto-ovo-vegetarian dietary pattern to prevent the occurrence and progression of SO.
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http://dx.doi.org/10.1016/j.nut.2021.111386DOI Listing
June 2021

Clinical Observation of Gene Polymorphism of Olanzapine or Aprepitant in Prevention of CINV.

Pharmgenomics Pers Med 2021 15;14:867-875. Epub 2021 Jul 15.

Department of Medical Oncology, Ordos Central Hospital, Ordos, 017000, People's Republic of China.

Objective: The present study aims to investigate the correlation between the gene polymorphisms of the multidrug resistance protein 1 (ABCB1), the intron region of transcriptional factor (GTF2E1) and catechol--methyltransferase (COMT), dopamine receptor (DRD2), and the control of chemotherapy-induced nausea and vomiting (CINV) by olanzapine or aprepitant in a Chinese population under a fractionated cisplatin dosing pattern.

Methods: Antiemetic treatment with 5 mg of olanzapine or aprepitant triplet therapy was conducted in 210 patients with malignancies receiving cisplatin multi-day chemotherapy. The general data on the patients were collected with the evaluation of the rate of complete protection (TP), complete remission (CR), complete control (TC), and time to first vomiting, the functional living index-emesis (FLIE) scale, and side effects in the acute and delayed phases. The DNA mass spectrometry detected the gene polymorphisms of ABCB1, GTF2E1, COMT, and DRD2, and the correlation with TP was analyzed.

Results: 1) There were no statistically significant differences in the TP, CR, TC, time of first vomiting, and FLIE index at different phases between the 5mg of olanzapine group and the aprepitant group (P > 0.05). 2) The main side effect in the olanzapine group was drowsiness (P = 0.00), and in the aprepitant group was constipation (P = 0.02). 3) The distributions of each genotype were in the Hardy-Weinberg (H-W) equilibrium. Univariate analysis showed that in the olanzapine group, delayed-phase TP was correlated with the ABCB1 rs1045642 non-TT (P = 0.01) genotype.

Conclusion: The present study revealed that females and the rs1045642TT genotype were independent risk factors for delayed-phase CINV in the northern Chinese population, which provided a scientific basis for subsequent CINV-related analysis of high-risk factors in Chinese patients.
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http://dx.doi.org/10.2147/PGPM.S317229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8289460PMC
July 2021

Toward Unusual-High Hole Mobility of p-Channel Field-Effect-Transistors.

Small 2021 Jul 19:e2102323. Epub 2021 Jul 19.

School of Physics, School of Microelectronics, State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, P. R. China.

The relative low hole mobility of p-channel building block device challenges the continued miniaturization of modern electronic chips. Metal-semiconductor junction is always an efficient strategy to control the carrier concentration of channel semiconductor, benefiting the carrier mobility regulation of building block device. In this work, complementary metal oxide semiconductor (CMOS)-compatible metals are selected to deposit on the surface of the important p-channel building block of GaSb nanowire field-effect-transistors (NWFETs), demonstrating the efficient strategy of hole mobility enhancement by metal-semiconductor junction. When deposited with lower work function metal of Al, the peak hole mobility of GaSb NWFET can be enhanced to as high as ≈3372 cm V s , showing three times than the un-deposited one. The as-studied metal-semiconductor junction is also efficient for the hole mobility enhancement of other p-channel devices, such as GaAs NWFET, GaAs film FET, and WSe FET. With the enhanced mobility, the as-constructed CMOS inverter shows good invert characteristics, showing a relatively high gain of ≈18.1. All results may be regarded as important advances to the next-generation electronics.
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http://dx.doi.org/10.1002/smll.202102323DOI Listing
July 2021

CaMKII and Ca3.2 T-type calcium channel mediate Connexin-43-dependent inflammation by activating astrocytes in vincristine-induced neuropathic pain.

Cell Biol Toxicol 2021 Jul 20. Epub 2021 Jul 20.

School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing, 210009, China.

Vincristine (VCR), an alkaloid isolated from vinca, is a commonly used chemotherapeutic drug. However, VCR therapy can lead to dose-dependent peripheral neurotoxicity, mainly manifesting as neuropathic pain, which is one of the dominant reasons for limiting its utility. Experimentally, we discovered that VCR-induced neuropathic pain (VINP) was accompanied by astrocyte activation; the upregulation of phospho-CaMKII (p-CaMKII), Ca3.2, and Connexin-43 (Cx43) expression; and the production and release of inflammatory cytokines and chemokines in the spinal cord. Similar situations were also observed in astrocyte cultures. Interestingly, these alterations were all reversed by intrathecal injection of KN-93 (a CaMKII inhibitor) or L-Ascorbic acid (a Ca3.2 inhibitor). In addition, KN-93 and L-Ascorbic acid inhibited the increase in [Ca] associated with astrocyte activation. We also verified that knocking down or inhibiting Cx43 level via intrathecal injection of Cx43 siRNA or Gap27 (a Cx43 mimetic peptide) relieved pain hypersensitivity and reduced the release of inflammatory factors; however, they did not affect astrocyte activation or p-CaMKII and Ca3.2 expression. Besides, the overexpression of Cx43 through the transfection of the Cx43 plasmid did not affect p-CaMKII and Ca3.2 expressions in vitro. Therefore, CaMKII and Ca3.2 may activate astrocytes by increasing [Ca], thereby mediating Cx43-dependent inflammation in VINP. Moreover, we demonstrated that the CaMKII signalling pathway was involved in VCR-induced inflammation, apoptosis, and mitochondrial damage. Collectively, our findings show a novel mechanism by which CaMKII and Ca3.2 mediate Cx43-dependent inflammation by activating astrocytes in neuropathic pain induced by VCR.
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http://dx.doi.org/10.1007/s10565-021-09631-yDOI Listing
July 2021

Danshensu inhibits the IL-1β-induced inflammatory response in chondrocytes and osteoarthritis possibly via suppressing NF-κB signaling pathway.

Mol Med 2021 Jul 20;27(1):80. Epub 2021 Jul 20.

Shengli Clinical Medical College of Fujian Medical University, Fuzhou, 350004, Fujian Province, People's Republic of China.

Purpose: Osteoarthritis (OA) is the most common inflammatory disease associated with pain and cartilage destruction. Interleukin (IL)-1β is widely used to induce inflammatory response in OA models. This study aimed to explore the role of Danshensu (DSS) in IL-1β-induced inflammatory responses in OA.

Methods: IL-1β was used to induce chondrocyte inflammation. Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay. IL-6, COX-2, TNF-α, and iNOS mRNA levels were detected by qRT-PCR. MMP3, MMP13, ADAMTS4, ADAMTS5, Aggrecan, Collagen, p-IκBα, and p-p65 protein levels were detected by Western blot. An OA mouse model was established by surgical destabilization of the medial meniscus (DMM), and the Osteoarthritis Research Society International (OARSI) score was evaluated by H&E staining.

Results: DSS did not affect the levels of inflammatory indicators including IL-6, COX-2, TNF-α, iNOS, PEG2, and NO but suppressed COX-2 and iNOS protein expression in IL-1β treated chondrocytes. In addition, DSS downregulated IL-1β-enhanced expression of MMP3, MMP13, ADAMTS4, and ADAMTS5 and upregulated aggrecan and collagen expression. Moreover, DSS significantly inhibited IL-1β-induced phosphorylation of p-IκBα and p-p65 in a dose-dependent manner in chondrocytes, suggesting it plays a role in the NF-κB signaling pathway. Furthermore, DSS significantly reduced DMM-induced cartilage OARSI score in mice, further demonstrating its protective role in OA progression in vivo.

Conclusions: Our study revealed the protective role of DSS in OA, suggesting that DSS might act as a potential treatment for OA.
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http://dx.doi.org/10.1186/s10020-021-00329-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8290616PMC
July 2021

Dose tailoring of tacrolimus based on a non-linear pharmacokinetic model in children with refractory nephrotic syndrome.

Int Immunopharmacol 2021 Jul 17;98:107827. Epub 2021 Jul 17.

Department of Pharmacy, Shanghai Chest Hospital, Shanghai, China. Electronic address:

The population pharmacokinetics (PPK) of tacrolimus (TAC) in children with refractory nephrotic syndrome (RNS) have not been well-characterized. This study aimed to investigate the significant factors affecting the TAC PPK characteristics of children with RNS and to optimize the dosing regimen. A total of 494 concentrations from 108 children were obtained from routine therapeutic drug monitoring between 2016 and 2018. Information regarding the demographic features, laboratory test results, genetic polymorphisms of CYP3A5 (rs776746) and co-therapy medications were collected. PPK analysis was performed using the nonlinear mixed-effects modelling (NONMEM) software and two modelling strategies (the linear one-compartment model and nonlinear Michaelis-Menten model) were evaluated and compared. CYP3A5 genotype, weight, daily dose of TAC and daily dose of diltiazem were retained in the final linear model. The absorption rate constant (Ka) was set at 4.48 h in the linear model, and the apparent clearance (CL/F) and volume of distribution (V/F) in the final linear model were 14.2 L/h and 172 L, respectively. CYP3A5 genotype, weight and daily dose of diltiazem were the significant factors retained in the final nonlinear model. The maximal dose rate (V) and the average steady-state concentration at half-Vmax (K) in the final nonlinear model were 2.15 mg/day and 0.845 ng/ml, respectively. The nonlinear model described the pharmacokinetic data of TAC better than the linear model in children with RNS. A dosing regimen was proposed based on weight, CYP3A5 genotype and daily dose of diltiazem according to the final nonlinear PK model, which may facilitate individualized drug therapy with TAC.
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http://dx.doi.org/10.1016/j.intimp.2021.107827DOI Listing
July 2021

Tannic Acid: A green and efficient stabilizer of Au, Ag, Cu and Pd nanoparticles for the 4-Nitrophenol Reduction, Suzuki-Miyaura coupling reactions and click reactions in aqueous solution.

J Colloid Interface Sci 2021 Jul 8;604:281-291. Epub 2021 Jul 8.

College of polymer science and engineering, Sichuan University, Chengdu 610065, China. Electronic address:

Due to the good electrical, optical, magnetic, catalytic properties, transition metal nanoparticles (TMNPs) have been becoming more and more interesting in the fileds of environment, material, biomedicine, catalysis, and so on. Here, tannic acid (TA) is used as a green and efficient stabilizer to fabricate all kinds of TMNPs including AuNPs, AgNPs, CuNPs and PdNPs. These TMNPs possess small sizes ranging from 1 nm to 6 nm, which is conducive to several catalytic reactions in aqueous solution, such as 4-nitrophenol (4-NP) reduction, CuAAC reactions and Suzuki-Miyaura coupling reactions. AuNPs and PdNPs are found to have distinctly higher catalytic activities than AgNPs and CuNPs in the 4-NP reduction process. Especially, PdNPs show the highest catalytic activities with TOF up to 7200 h in the 4-NP reduction. Furthermore, PdNPs also exhibit satisfying catalytic performance in the Suzuki-Miyaura coupling process, and CuNPs are catalytically active in the copper-catalyzed azide alkyne cycloaddition (CuAAC) reactions. The applicability and generality of PdNPs and CuNPs are respectively confirmed via the reaction between different substrates in the Suzuki-Miyaura coupling reactions and the CuAAC reactions. This work present a simple, fast, green and efficient strategy to synthesize TMNPs for multiple catalysis.
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http://dx.doi.org/10.1016/j.jcis.2021.07.015DOI Listing
July 2021

Detection of cell-surface sialic acids and photodynamic eradication of cancer cells using dye-modified polydopamine-coated gold nanobipyramids.

J Mater Chem B 2021 Jul;9(29):5780-5784

Department of Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong, China.

A nanoprobe based on polydopamine-coated gold nanobipyramids surface modified with molecules of a phenylboronic acid-substituted distyryl boron dipyrromethene has been fabricated and characterised using various physical and spectroscopic methods. It serves as an ultrasensitive sensor for sialic acids on the surface of cancer cells based on its dual surface-enhanced Raman scattering and fluorescence response. This biomarker can also trigger the photodynamic activity of these nanobipyramids, effectively eradicating the cancer cells mainly through apoptosis as shown by various bioassays.
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http://dx.doi.org/10.1039/d1tb01274fDOI Listing
July 2021

Genetically encoded FRET fluorescent sensor designed for detecting MOF histone acetyltransferase activity in vitro and in living cells.

Anal Bioanal Chem 2021 Jul 16. Epub 2021 Jul 16.

Hefei National Laboratory for Physical Sciences at Microscale, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230027, Anhui, China.

Acetylation of lysine in the histone H4 N-terminal is one of the most significant epigenetic modifications in cells. Aberrant changes involving lysine acetylation modification are commonly reported in multiple types of cancers. Currently, whether it is for in vivo or in vitro, there are limited approaches for the detection of H4 lysine acetylation levels. In particular, the main problems are the high cost and the cumbersome detection process, such as for radioactive C isotope detection. Therefore, there is an important need to develop a simple, fast, and low-cost means of detection. In this study, we reported the development of a gene-coding protein sensor. This protein sensor was designed based on the mechanism of fluorescence resonance energy transfer (FRET). The four kinds of sensors, varying from substrate and linker length, were evaluated, with ~20% increases in response efficiency. Next, sensors with different lysine mutation sites in the substrate sequence or mutation of key amino acids in the binding domain were also analyzed to determine site specificity. We found single-site lysine mutant could not cause a significant decrease in response efficiency. Furthermore, addition of MG149, a histone acetyltransferase inhibitor, resulted in a decrease in the ratio change value. Moreover, histone deacetylase1 HDAC1 was also found to reduce the ratio change values when added to reaction system. Finally, the optimized sensor was applied to living cells and established to provide a sensitive response with overexpression and knockdown of MOF (males absent on the first). These results indicated that the sensor can be used for screening chemical drugs regulating H4 N-terminal lysine acetylation level in vitro, as well as monitoring dynamic changes of lysine acetylation levels in living cells.
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http://dx.doi.org/10.1007/s00216-021-03528-9DOI Listing
July 2021

Meat species identification accuracy improvement using sample set portioning based on joint x-y distance and laser-induced breakdown spectroscopy.

Appl Opt 2021 Jul;60(20):5826-5831

Laser-induced breakdown spectroscopy (LIBS) was suitable for the identification of meat species due to fast and less sample preparation. However, the problem of low accuracy rate of the recognition model caused by improper selection of training set samples by random split has severely restricted the development of LIBS in meat detection. Sample set portioning based on the joint x-y distance (SPXY) method was applied for dividing the meat spectra into a training set and a test set. Then, the five kinds of meat samples (shrimp, chicken, beef, scallop, and pig liver) were classified by the support vector machine (SVM). With the random split method, Kennard-Stone method, and SPXY method, the recognition accuracies of the SVM model were 90.44%, 91.95%, and 94.35%, respectively. The multidimensional scaling method was used to visualize the results of the sample split for the interpretation of the classification. The results showed that the identification performance of the SPXY method combined with the SVM model was best, and the accuracy rates of shrimp, chicken, beef, scallop, and pig liver were 100.00%, 100.00%, 100.00%, 78.57%, and 92.00%, respectively. Moreover, to verify the broad adaptability of the SPXY method, the linear discriminant analysis model, the K-nearest neighbor model, and the ensemble learning model were applied as the meat species identification model. The results demonstrated that the accuracy rate of the classification model can be improved with the SPXY method. In light of the findings, the proposed sample portioning method can improve the accuracy rate of the recognition model using LIBS.
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http://dx.doi.org/10.1364/AO.430980DOI Listing
July 2021

Clinical features and survival analysis of 97 coronavirus disease 2019 (COVID-19) patients.

Ann Palliat Med 2021 Jul 5. Epub 2021 Jul 5.

Department of Chronic Disease Management Center, Beijing Youan Hospital, Capital Medical University, Beijing, China.

Background: We aim to investigate the clinical characteristics and survival rate of coronavirus disease 2019 (COVID-19) patients.

Methods: Ninety-seven COVID-19 patients were enrolled. The laboratory results, lung imaging and medical treatment were compared. Patients were followed up after 1 year, and the Kaplan-Meier test was used for survival analysis.

Results: Compared with the non-severe group, the age of the severe group was older, and the proportion of concomitant diseases were higher. As fever was the primary clinical manifestation, dyspnea and anorexia were more common in severe patients. Lung imaging manifestations and laboratory indicators were worse in the severe group. Accordingly, the treatment of glucocorticoid, antibiotics, and advanced life support were in high proportion. Of the 97 patients with COVID-19, 4 severe patients died within one month during the 1-year follow-up, with the median survival time of 47.0 weeks (95% CI: 45.1-48.9).

Conclusions: Severe cases of COVID-19 are characterized by advanced age, more concomitant diseases and complications, which lead to a decreased short-term survival rate. However, there were no deaths after one month, which implied a good prognosis if the risk period were passed smoothly.
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http://dx.doi.org/10.21037/apm-21-393DOI Listing
July 2021

A Plasmon-Enhanced SnSe Photodetector by Non-Contact Ag Nanoparticles.

Small 2021 Jul 14:e2102351. Epub 2021 Jul 14.

School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, China.

The 2D layered materials are promising candidates for broadband, low-cost photodetectors. One deficiency of 2D materials is the relatively low absorbance of light, limiting the applications of the 2D photodetectors. Doping of plasmonic nanoparticles into 2D materials may enhance the optical absorbance owing to the localized surface plasmonic resonance (LSPR) effect; however, considerable defects may be introduced into the 2D materials at the same time, resulting in certain degradation of device performance. Here, a novel design of 2D photodetectors with enhanced photoresponsivity by non-contact plasmonic nanoparticles (NPs) is proposed, consisting of a hybrid structure of few-layer SnSe transferred a fused silica (SiO ) plate with embedded Ag NPs. The system of Ag NPs-in-SiO shows strong LSPR effect with significantly enhanced optical absorption, acting on SnSe in a non-contact configuration. Benefiting from well-preserved intrinsic features of SnSe and LSPR effect, the responsivity of the photodetector is enhanced by 881 times with the bias voltage of 0.1 V, which is superior to previously reported results of plasmon-enhanced 2D photodetectors. Moreover, the SiO with embedded Ag NPs is recyclable and can be easy to be recombined with different 2D materials. This work offers additional strategy for development of efficient, low-cost 2D photodetectors by using plasmonic NPs.
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http://dx.doi.org/10.1002/smll.202102351DOI Listing
July 2021

Asphyxia caused by delayed subglottic stenosis after neck trauma.

Forensic Sci Med Pathol 2021 Jul 14. Epub 2021 Jul 14.

Department of Forensic Medicine, Nanjing Medical University, Nanjing, 211166, Jiangsu, China.

Delayed subglottic stenosis (SGS) is an unusual complication. Here, we report a particular case of delayed SGS. A 17-year-old female suffered extensive injuries including severe neck trauma in a car accident, and complained of dyspnea after 30 days. Tracheal stenosis was observed by fiber optic bronchoscopy, but no specific treatment was administered to the patient. While being transferred to a tertiary hospital 3 days later, the patient fell into deep coma due to hypoxia, and died of hypoxic-ischemic encephalopathy and severe pulmonary infection in the intensive care unit (ICU) 58 days later. Postmortem autopsy and pathological investigation revealed tracheal stenosis 3.0 cm below the vocal cords with a diameter of 0.5 cm, which was caused by a cricoid cartilage fracture, fibrous tissue proliferation and inflammatory cell infiltration. We believed that external forces caused the cricoid fracture and mucosal damage, and after a month of fibrous repair, scar tissue formed the stenosis and caused her death. This report describes a rare condition in which slowly progressive intralaryngeal stenosis formation after external neck trauma could cause asphyxial death in a previously asymptomatic adult.
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http://dx.doi.org/10.1007/s12024-021-00391-zDOI Listing
July 2021

Identification of a Novel Immune-Related CpG Methylation Signature to Predict Prognosis in Stage II/III Colorectal Cancer.

Front Genet 2021 28;12:684349. Epub 2021 Jun 28.

Department of Radiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.

With the increasing incidence of colorectal cancer (CRC) and continued difficulty in treating it using immunotherapy, there is an urgent need to identify an effective immune-related biomarker associated with the survival and prognosis of patients with this disease. DNA methylation plays an essential role in maintaining cellular function, and changes in methylation patterns may contribute to the development of autoimmunity, aging, and cancer. In this study, we aimed to identify a novel immune-related methylated signature to aid in predicting the prognosis of patients with CRC. We investigated DNA methylation patterns in patients with stage II/III CRC using datasets from The cancer genome atlas (TCGA). Overall, 182 patients were randomly divided into training ( = 127) and test groups ( = 55). In the training group, five immune-related methylated CG sites (cg11621464, cg13565656, cg18976437, cg20505223, and cg20528583) were identified, and CG site-based risk scores were calculated using univariate Cox proportional hazards regression in patients with stage II/III CRC. Multivariate Cox regression analysis indicated that methylated signature was independent of other clinical parameters. The Kaplan-Meier analysis results showed that CG site-based risk scores could significantly help distinguish between high- and low-risk patients in both the training ( = 0.000296) and test groups ( = 0.022). The area under the receiver operating characteristic curve in the training and test groups were estimated to be 0.771 and 0.724, respectively, for prognosis prediction. Finally, stratified analysis results suggested the remarkable prognostic value of CG site-based risk scores in CRC subtypes. We identified five methylated CG sites that could be used as an efficient overall survival (OS)-related biomarker for stage II/III CRC patients.
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http://dx.doi.org/10.3389/fgene.2021.684349DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8273301PMC
June 2021

Customized bus passenger boarding and deboarding planning optimization model with the least number of contacts between passengers during COVID-19.

Physica A 2021 Nov 8;582:126244. Epub 2021 Jul 8.

School of Economics & Management, Wuyi University, Guangdong, 529020, China.

The COVID-19 epidemic has had a major impact on people's normal travel. Optimizing the control of the number of passengers boarding and deboarding the customized bus (CB) at CB stops can reduce the contact between passengers in the course of travel, which is meaningful for COVID-19 epidemic prevention and control. In this paper, a dynamic programming model based on nonlinear integer programming (NIP) is established to study the problem of boarding and alighting planning at various CB stops under the influence of COVID-19. Using Gurobi 9.1.1 solver, the optimal plan for passengers boarding and deboarding CB buses could be obtained. Besides, the mathematical model established in this paper can obtain the minimum value of the total number of contacts between passengers during travel under different CB numbers. It is found that the model solution results eventually form a Pareto frontier. When the number of CB buses increases, the total number of contacts between passengers will decrease This study has positive significance for ensuring the normal travel of passengers during the COVID-19 epidemic, and provides useful references for the studies about the planning of the customized bus.
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http://dx.doi.org/10.1016/j.physa.2021.126244DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8265187PMC
November 2021

Systematic mining of fungal chimeric terpene synthases using an efficient precursor-providing yeast chassis.

Proc Natl Acad Sci U S A 2021 Jul;118(29)

Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education, Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, People's Republic of China;

Chimeric terpene synthases, which consist of C-terminal prenyltransferase (PT) and N-terminal class I terpene synthase (TS) domains (termed PTTSs here), is unique to fungi and produces structurally diverse di- and sesterterpenes. Prior to this study, 20 PTTSs had been functionally characterized. Our understanding of the origin and functional evolution of genes is limited. Our systematic search of sequenced fungal genomes among diverse taxa revealed that genes were restricted to Dikarya. Phylogenetic findings indicated different potential models of the origin and evolution of genes. One was that genes originated in the common Dikarya ancestor and then underwent frequent gene loss among various subsequent lineages. To understand their functional evolution, we selected 74 genes for biochemical characterization in an efficient precursor-providing yeast system employing chassis-based, robot-assisted, high-throughput automatic assembly. We found 34 genes that encoded active enzymes and collectively produced 24 di- and sesterterpenes. About half of these di- and sesterterpenes were also the products of the 20 known PTTSs, indicating functional conservation, whereas the PTTS products included the previously unknown sesterterpenes, sesterevisene (1), and sesterorbiculene (2), suggesting that a diversity of PTTS products awaits discovery. Separating functional PTTSs into two monophyletic groups implied that an early gene duplication event occurred during the evolution of the PTTS family followed by functional divergence with the characteristics of distinct cyclization mechanisms.
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http://dx.doi.org/10.1073/pnas.2023247118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8307374PMC
July 2021

Accurate transcriptome assembly by Nanopore RNA sequencing reveals novel functional transcripts in hepatocellular carcinoma.

Cancer Sci 2021 Jul 13. Epub 2021 Jul 13.

The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, China.

The long reads of Nanopore sequencing permit accurate transcript assembly and ease in discovering novel transcripts with potentially important functions in cancers. The wide adoption of Nanopore sequencing for transcript quantification, however, is largely limited by high costs. To address this issue, we developed a bioinformatics software, NovelQuant, that can specifically quantify long-read-assembled novel transcripts with short-read sequencing data. Nanopore Direct RNA Sequencing was carried out on three hepatocellular carcinoma (HCC) patients' tumor, matched portal vein tumor thrombus, and peritumor to reconstruct the HCC transcriptome. Then, based on the reconstructed transcriptome, NovelQuant was applied on Illumina RNA sequencing data of 59 HCC patients' tumor and paired peritumor to quantify novel transcripts. Our further analysis revealed 361 novel transcripts dysregulated in HCC and that 101 of them were significantly associated with prognosis. There were 19 novel prognostic transcripts predicted to be long noncoding RNAs (lncRNAs), and some of them had regulatory targets that were reported to be associated with HCC. Additionally, 42 novel prognostic transcripts were predicted to be protein-coding mRNAs, and many of them could be involved in xenobiotic metabolism. Moreover, the tumor-suppressive roles of two representative novel prognostic transcripts, CDO1-novel (lncRNA) and CYP2A6-novel (protein-coding mRNA), were further functionally validated during HCC progression. Overall, the current study shows a possibility of combining long- and short-read sequencing to explore functionally important novel transcripts in HCC with accuracy and cost-efficiency, which expands the pool of molecular biomarkers that could enhance our understanding of the molecular mechanisms of HCC.
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http://dx.doi.org/10.1111/cas.15058DOI Listing
July 2021

The Effect of the Antimicrobial Peptide Plectasin on the Growth Performance, Intestinal Health, and Immune Function of Yellow-Feathered Chickens.

Front Vet Sci 2021 23;8:688611. Epub 2021 Jun 23.

Lingnan Guangdong Laboratory of Modern Agriculture, College of Animal Science, South China Agricultural University, Guangzhou, China.

The goal of the study was to test the effects of an antibiotic substitute, plectasin, on the growth performance, immune function, intestinal morphology and structure, intestinal microflora, ileal mucosal layer construction and tight junctions, ileal immune-related cytokines, and blood biochemical indices of yellow-feathered chickens. A total of 1,500 one-day-old yellow-feathered chicks were randomly divided into four dietary treatment groups with five replicates in each group and 75 yellow-feathered chicks in each replication, as follows: basal diet (group A); basal diet supplemented with 10 mg enramycin/kg of diet (group B), basal diet supplemented with 100 mg plectasin/kg of diet (group C), and basal diet supplemented with 200 mg plectasin/kg of diet (group D). It was found that the dietary antimicrobial peptide plectasin could improve the ADG and had better F/G for the overall period of 1-63 days. Dietary plectasin can enhance H9N2 avian influenza virus (AIV) and Newcastle disease virus (NDV) antibody levels of yellow-feathered chickens at 21, and 35 days of age. Dietary plectasin can enhance the intestine structure, inhibit and proinflammatory cytokines in the ileum, and ameliorate the blood biochemical indices of yellow-feathered chickens at 21 days of age. This study indicates that the antimicrobial peptide plectasin has beneficial effects on the growth performance, intestinal health and immune function of yellow-feathered chickens.
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http://dx.doi.org/10.3389/fvets.2021.688611DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8260853PMC
June 2021

Genetics of Resistance to Common Root Rot (Spot Blotch), Crown Rot, and Sharp Eyespot in Wheat.

Front Genet 2021 23;12:699342. Epub 2021 Jun 23.

State Key Laboratory of North China Crop Improvement and Regulation, College of Plant Protection, Hebei Agricultural University, Baoding, China.

Due to soil changes, high density planting, and the use of straw-returning methods, wheat common root rot (spot blotch), crown rot (FCR), and sharp eyespot (sheath blight) have become severe threats to global wheat production. Only a few wheat genotypes show moderate resistance to these root and crown rot fungal diseases, and the genetic determinants of wheat resistance to these devastating diseases are poorly understood. This review summarizes recent results of genetic studies of wheat resistance to common root rot, crown rot, and sharp eyespot. Wheat germplasm with relatively higher resistance are highlighted and genetic loci controlling the resistance to each disease are summarized.
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http://dx.doi.org/10.3389/fgene.2021.699342DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8260946PMC
June 2021

GhMYB7 promotes secondary wall cellulose deposition in cotton fibers by regulating GhCesA gene expression through three distinct cis-elements.

New Phytol 2021 Jul 10. Epub 2021 Jul 10.

Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.

Cotton fiber is the most important source for natural textiles. The secondary cell walls (SCWs) of mature cotton fibers contain the highest proportion of cellulose content (> 90%) in any plant. The onset and progression of SCW cellulose synthesis need to be tightly controlled to balance fiber elongation and cell wall deposition. However, regulatory mechanisms that control cellulose synthesis during cotton fiber growth remain elusive. Here, we conducted genetic and functional analyses demonstrating that the R2R3-MYB GhMYB7 controls cotton fiber cellulose synthesis. Overexpression of GhMYB7 in cotton sped up SCW cellulose biosynthesis in fiber cells, and led to shorter fiber with thicker walls. By contrast, RNA interference (RNAi) silencing of GhMYB7 delayed fiber SCW cellulose synthesis and made elongated fiber with thinner walls. Furthermore, we demonstrate that GhMYB7 regulates cotton fiber SCW cellulose synthases by directly binding to three distinct cis-elements in respective GhCesA4, GhCesA7 and GhCesA8 promoters. We found that this regulatory mechanism of cellulose synthesis was hi-jacked also by other GhMYBs. Together, our findings uncover a hitherto-unknown mechanism that cotton fiber employs to regulate SCW cellulose synthesis. Our results also provide a strategy for genetic improvement of SCW thickness of cotton fiber.
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http://dx.doi.org/10.1111/nph.17612DOI Listing
July 2021

Sesquiterpene biosynthesis in a leafy liverwort Radula lindenbergiana Gottsche ex C. Hartm.

Phytochemistry 2021 Jul 6;190:112847. Epub 2021 Jul 6.

Department of Plant Sciences, University of Tennessee, Knoxville, TN, 37996, USA. Electronic address:

Liverworts (Marchantiophyta) are among the earliest diverging lineages of extant land plants. Among their unique features, most liverworts contain membrane-bound oil bodies, organelles that accumulate diverse secondary metabolites, especially terpenoids. In contrast to the rich information on liverwort terpenoid chemistry, little is known about their biosynthesis. Recently, terpenoid biosynthesis was studied in a model thalloid species Marchantiapolymorpha, in which sesquiterpenes and monoterpenes are biosynthesized by a new type of terpene synthases termed microbial terpene synthase-like (MTPSL) proteins. Here we study terpenoid biosynthesis in a leafy liverwort Radula lindenbergiana. Vegetative plants of R.lindenbergiana were found to contain a mixture of sesquiterpenes, with (E,E)-α-farnesene/β-curcumene and (Z)-β-bisabolene being the most abundant constituents. From the analysis of the R. lindenbergiana transcriptome, five full-length MTPSL genes were identified. They were designated RlMTPSL1-5, respectively. Recombinant RlMTPSL proteins were produced in Escherichia coli and tested for sesquiterpene synthase activities using farnesyl diphosphate (FPP) as substrate. All except RlMTPSL5 were demonstrated to catalyze the formation of different sesquiterpenes. RlMTPSL1 produced multiple sesquiterpenes with eremophilene and an unidentified sesquiterpene as major products. The major products of RlMTPSL2 and RlMTPSL3 were β-elemene and an unidentified sesquiterpene, respectively. RlMTPSL4 was also a multi-product sesquiterpene synthase with an unidentified sesquiterpene being the major product. Homology-based structural modeling was performed to understand the structural basis underlying different product profiles of the RlMTPSLs proteins. Most of the sesquiterpene products of the four active RlMTPSLs were also detected in R. lindenbergiana plants. Expression levels of the four RlMTPSL genes encoding active enzymes in vegetative plants were compared. In phylogenetic analysis, RlMTPSL genes were found to cluster together, indicating lineage-specific expansion of MTPSL genes in lineages leading to R.lindenbergiana and M. polymorpha. This study strengthens evidence for the contribution of MTPSL genes to terpenoid biosynthesis in liverworts.
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http://dx.doi.org/10.1016/j.phytochem.2021.112847DOI Listing
July 2021

Development of pullulan/carboxylated cellulose nanocrystal/tea polyphenol bionanocomposite films for active food packaging.

Int J Biol Macromol 2021 Jul 5;186:405-413. Epub 2021 Jul 5.

College of Life Sciences, Fujian Normal University, Fuzhou 350117, China. Electronic address:

In this study, novel active films based on pullulan and carboxylated cellulose nanocrystal (C-CNC) incorporated with tea polyphenol (TP) was prepared by solution casting method. The effect of TP addition on the microstructural, mechanical, barrier, optical, functional properties of the resultant pullulan/C-CNC/TP (PC-TP) bionanocomposite films was systematically evaluated. Scanning electron microscopy showed that an appropriate TP adding was well distributed within the PC-TP bionanocomposite matrix. Fourier-transform infrared further revealed that new hydrogen bond was formed among the pullulan, C-CNC, TP. Addition of TP at an appropriate level (3%, w/w, on a dry basis of the weight of pullulan and C-CNC) led to stronger intermolecular interactions and more compact microstructure, and thus enhanced the water barrier properties, thermal stability and tensile strength of the resultant bionanocomposite films. Nevertheless, overloading of TP in the bionanocomposite films might produce some aggregations and thus have negative effects on their performance. In addition, the incorporation of TP significantly improved the UV-barrier properties, antioxidant activity and antimicrobial activity of PC-TP bionanocomposite films, while induced a decrease in the transmittance. These results revealed that PC-TP bionanocomposite films with TP at appropriate levels had potential to be used as active food packaging.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.07.025DOI Listing
July 2021
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