Publications by authors named "Juan Huang"

661 Publications

The Role of m6A Epigenetic Modification in the Treatment of Colorectal Cancer Immune Checkpoint Inhibitors.

Front Immunol 2021 6;12:802049. Epub 2022 Jan 6.

Department of Hematology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.

Tumor immunotherapy, one of the efficient therapies in cancers, has been called to the scientific community's increasing attention lately. Among them, immune checkpoint inhibitors, providing entirely new modalities to treat cancer by leveraging the patient's immune system. They are first-line treatments for varieties of advanced malignancy, such as melanoma, gastrointestinal tumor, esophageal cancer. Although immune checkpoint inhibitors (ICIs) treatment has been successful in different cancers, drug resistance and relapses are common, such as in colorectal cancer. Therefore, it is necessary to improve the efficacy of immune checkpoint therapy for cancer patients who do not respond or lowly response to current treatments. N6-methyladenosine (m6A), as a critical regulator of transcript expression, is the most frequently internal modification of mRNA in the human body. Recently, it has been proposed that m6A epigenetic modification is a potential driver of tumor drug resistance. In this report, we will briefly outline the relevant mechanisms, general treatment status of immune checkpoint inhibitors in colorectal cancer, how m6A epigenetic modifications regulate the response of ICIs in CRC and provide new strategies for overcoming the resistance of ICIs in CRC.
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http://dx.doi.org/10.3389/fimmu.2021.802049DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8771774PMC
January 2022

UL11 Protein Is a Key Participant of the Duck Plague Virus in Its Life Cycle.

Front Microbiol 2021 4;12:792361. Epub 2022 Jan 4.

Research Center of Avian Diseases, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.

Tegument protein UL11 plays a critical role in the life cycle of herpesviruses. The UL11 protein of herpesviruses is important for viral particle entry, release, assembly, and secondary envelopment. Lipid raft is cholesterol-rich functional microdomains in cell membranes, which plays an important role in signal transduction and substance transport. Flotillin and prohibition, which are considered to be specific markers of lipid raft. However, little is known about the function of duck plague virus (DPV) UL11 in the life cycle of the viruses and the relationship between the lipid raft and UL11. In this study, an interference plasmid shRNA126 for UL11 was used. Results showed that UL11 is involved in the replication, cell to cell spread, viral particle assembly, and release processes. Furthermore, UL11 was verified that it could interact with the lipid raft through sucrose density gradient centrifugation and that function correlates with the second glycine of the UL11. When the lipid raft was depleted using the methyl-β-cyclodextrin, the release of the DPV was decreased. Moreover, UL11 can decrease several relative viral genes mRNA levels by qRT-PCR and Western blot test. Altogether, these results highlight an important role for UL11 protein in the viral replication cycle.
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http://dx.doi.org/10.3389/fmicb.2021.792361DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8764364PMC
January 2022

A Combination of Biomarkers Predict Response to Immune Checkpoint Blockade Therapy in Non-Small Cell Lung Cancer.

Front Immunol 2021 23;12:813331. Epub 2021 Dec 23.

Department of Hematology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.

Immune checkpoint blockade (ICB) therapy has provided clinical benefits for patients with advanced non-small-cell lung cancer (NSCLC), but the majority still do not respond. Although a few biomarkers of ICB treatment response have been developed, the predictive power of these biomarkers showed substantial variation across datasets. Therefore, predicting response to ICB therapy remains a challenge. Here, we provided a concise combinatorial strategy for predicting ICB therapy response and constructed the ICB treatment signature (ITS) in lung cancer. The prediction performance of ITS has been validated in an independent ICB treatment cohort of NSCLC, where patients with higher ITS score were significantly associated with longer progression-free survival and better response. And ITS score was more powerful than traditional biomarkers, such as TMB and PD-L1, in predicting the ICB treatment response in NSCLC. In addition, ITS scores still had predictive effects in other cancer data sets, showing strong scalability and robustness. Further research showed that a high ITS score represented comprehensive immune activation characteristics including activated immune cell infiltration, increased mutation load, and TCR diversity. In conclusion, our practice suggested that the combination of biomarkers will lead to a better prediction of ICB treatment prognosis, and the ITS score will provide NSCLC patients with better ICB treatment decisions.
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http://dx.doi.org/10.3389/fimmu.2021.813331DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8733693PMC
December 2021

Duck Plague Virus pUL48 Protein Activates the Immediate-Early Gene to Initiate the Transcription of the Virus Gene.

Front Microbiol 2021 23;12:795730. Epub 2021 Dec 23.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.

Duck plague caused by the duck plague virus (DPV) is an infectious disease that seriously harms the waterfowl breeding industry. The VP16 protein of α herpesvirus can bind to specific -acting elements upstream of the promoter of the immediate-early (IE, α) gene to promote the transcription of the IE gene, so it is also called the -inducer of IE gene (α-TIF). However, no studies on DPV α-TIF have been reported. This study investigated the DPV pUL48, a homolog of HSV-1 VP16, transcriptional activation region, target sequence, and viral protein affecting its transcriptional activation using a dual-luciferase reporter gene detection system, and pUL48 was identified as the α-TIF of DPV. (1) The regulation of pUL48 on DPV different gene promoters showed that pUL48 could activate all the promoters of IE genes (ICP4, ICP22, and ICP27) but not the promoters of early and late genes. (2) The activity of pUL48 to ICP4 and ICP22 promoters with different upstream lengths showed that pUL48 activated ICP4 and ICP22 promoters by acting on TAATGA (T) TAT element upstream of ICP4 promoter and TAATTATAT element upstream of ICP22 promoter, respectively. (3) Transcriptional activation of IE gene by truncated proteins of different lengths at the N-terminal of pUL48 was detected. The results showed that the transcriptional activation domain of pUL48 was amino acids 1-60 at the N-terminal, and amino acids 1-20 was its core region. In addition, it was found that pUL14, pUL46, and pUL47 significantly promoted the transcriptional activation of pUL48. The effects of loss of pUL47 and its nuclear localization signal on the nuclear entry and transcriptional activation function of pUL48 were further examined. The results showed that pUL47 could promote the nuclear entry of pUL48 through its nuclear localization signal at positions 40-50 and 768-777 amino acids, thus, enhancing the transcriptional activation function of pUL48 and synergistic promotion of viral gene transcription.
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http://dx.doi.org/10.3389/fmicb.2021.795730DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8733724PMC
December 2021

Clinical features of invasive fungal disease in children with no underlying disease.

Sci Rep 2022 Jan 7;12(1):208. Epub 2022 Jan 7.

Department of Pediatrics, Xiangya Hospital, Central South University, Xiangya Road, Changsha City, 410008, Hunan Province, People's Republic of China.

There is limited research into Invasive fungal disease (IFD) in children with no underlying disease. We undertook a retrospective study of children with IFD who did not suffer from another underlying disease, from June 2010 to March 2018 in Changsha, China. Nine children were identified. Eosinophil counts were elevated in six cases. The level of procalcitonin (PCT) was elevated in six cases. Fungal culture was positive in all patients, including eight cases of Cryptococcus neoformans and one case of Candida parapsilosis. 8.33 days following antifungal treatment, the body temperature of the eight patients affected by cryptococcal disease had returned to normal. Our study indicates that the primary pathogen in IFD was Cryptococcus neoformans in children who had no other underlying disease. Eosinophils can be considered to be indicators of cryptococcal infection. IFD in children with no other underlying disease has a satisfactory prognosis.
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http://dx.doi.org/10.1038/s41598-021-03099-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8742124PMC
January 2022

Association of , , Polymorphisms and Asthma in Chinese Han Children.

Front Cell Dev Biol 2021 15;9:759542. Epub 2021 Dec 15.

National Institution of Drug Clinical Trial, Xiangya Hospital, Central South University, Changsha, China.

Genome-wide association studies have identified interleukin 33 (), interleukin 1 receptor-like 1 (), interleukin 1 receptor accessory protein () as asthma susceptibility loci in Europeans. IL33, IL1RL1, and IL1RAP constitute a ligand-receptor complex. We analyzed associations of asthma susceptibility, eosinophilic airway inflammation, and response to inhaled corticosteroid (ICS) with single nucleotide polymorphisms (SNPs) of 3 genes encoding IL33, IL1RL1, and its coreceptor IL1RAP in Chinese Han nationality children. A total of 153 non-asthmatic children and 265 asthmatic children who visited the Xiangya Hospital between September 2015 and August 2019 were recruited for this study. Pulmonary function tests, peripheral blood eosinophil counts (PBEC), and fractional exhaled nitric oxide (FeNO) tests were performed before treatment, and 3 months after treatment. Each participant's DNA was extracted from the peripheral blood, and a Mass ARRAY system was used to genotype the SNPs. The T allele of rs4742170 in was associated with a risk of higher FeNO at baseline, and no improvement in FeNO and airway hyperresponsiveness was found after ICS treatment. The A allele of rs10208293 and C allele of rs13424006 in both were associated with lower susceptibility to asthma and lower FeNO. The TT genotype of rs1420101 and AA genotype of rs4142132 in were associated with a greater probability of improvement in PBEC after ICS treatment. IL33-IL1RL1-IL1RAP complex polymorphisms are associated with childhood asthma susceptibility, eosinophilic airway inflammation, and ICS response in Chinese Han children in Hunan. We speculate that IL33-IL1RL1-IL1RAP complex polymorphisms affect the development of asthma, airway inflammation, and subsequent ICS response in childhood.
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http://dx.doi.org/10.3389/fcell.2021.759542DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8714920PMC
December 2021

[Steroidogenic acute regulatory protein-related lipid transfer 4 (StarD4) promotes breast cancer cell proliferation and its mechanism].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2021 Dec;38(6):1118-1125

Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, P.R.China.

Oncogene StarD4 had the function of promoting proliferation and metastasis of triple-negative breast cancer (TNBC), but its clinical value and molecular mechanism are unknown. This paper found that StarD4 was highly expressed in cancer tissues of TNBC patients, and higher expression level of StarD4 in TNBC patient resulted in poorer prognosis. Based on transcriptomics of MDA-MB-231 cell model, the results of bioinformatics analysis showed that down-regulated expression level of StarD4 led to overall downregulation of cholesterol-relative genes and significant enrichment of cancer mechanism and pathway. Further analysis and investigation verified that StarD4 might cross-promote the protein stability of receptor ITGA5 through the cholesterol pathway to enhance TNBC progression, which provides guidance for clinical application of TNBC diagnosis and treatment.
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http://dx.doi.org/10.7507/1001-5515.202105008DOI Listing
December 2021

Characterization of Six Lactones in Cheddar Cheese and Their Sensory Interactions Studied by Odor Activity Values and Feller's Additive Model.

J Agric Food Chem 2022 Jan 27;70(1):301-308. Epub 2021 Dec 27.

Department of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai 201418, P.R. China.

To evaluate the perceptual interactions among important lactone compounds in cheddar cheese, a molecular-level flavoromic approach, in combination with perceptual interaction analysis, was applied. Six aroma-active lactones with flavor dilution factors ranging from 4 to 128 were identified in three cheddar samples by gas chromatography-olfactometry-mass spectrometry. Odor thresholds of these six aroma-active lactones were determined with values from 7.16 to 30.03 μg/kg using a deodorized cheddar matrix. The odor activity value approach demonstrated complicated interactions among the 15 binary mixtures of six important lactones, including additive, synergistic, or masking effects. Based on partial differential odor intensities, each lactone with similar degrees of perceptual interactions in binary mixtures tends to present synergistic or masking effects. Owing to the difference in the chemical structure and mixture composition, δ-dodecalactone and γ-dodecalactone caused promotive and inhibitory effects on the expression of lactone fruity aroma, respectively.
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http://dx.doi.org/10.1021/acs.jafc.1c07924DOI Listing
January 2022

The Broad Immunomodulatory Effects of IL-7 and Its Application In Vaccines.

Front Immunol 2021 10;12:680442. Epub 2021 Dec 10.

Research Center of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, China.

Interleukin-7 (IL-7) is produced by stromal cells, keratinocytes, and epithelial cells in host tissues or tumors and exerts a wide range of immune effects mediated by the IL-7 receptor (IL-7R). IL-7 is primarily involved in regulating the development of B cells, T cells, natural killer cells, and dendritic cells the JAK-STAT, PI3K-Akt, and MAPK pathways. This cytokine participates in the early generation of lymphocyte subsets and maintain the survival of all lymphocyte subsets; in particular, IL-7 is essential for orchestrating the rearrangement of immunoglobulin genes and T-cell receptor genes in precursor B and T cells, respectively. In addition, IL-7 can aid the activation of immune cells in anti-virus and anti-tumor immunity and plays important roles in the restoration of immune function. These biological functions of IL-7 make it an important molecular adjuvant to improve vaccine efficacy as it can promote and extend systemic immune responses against pathogens by prolonging lymphocyte survival, enhancing effector cell activity, and increasing antigen-specific memory cell production. This review focuses on the biological function and mechanism of IL-7 and summarizes its contribution towards improved vaccine efficacy. We hope to provide a thorough overview of this cytokine and provide strategies for the development of the future vaccines.
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http://dx.doi.org/10.3389/fimmu.2021.680442DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8702497PMC
December 2021

Mesenchymal stem cells after the proprocessing of tanshinone IIA attenuate cognitive deficits and oxidative stress injury in an amyloid β-peptide (25-35)-induced rodent model of Alzheimer's disease.

Neuroreport 2022 01;33(2):61-71

Department of Neurology, The Third Affiliated Hospital of Zunyi Medical University, The First People's Hospital of Zunyi, Zunyi.

Objectives: To verify whether mesenchymal stem cells cocultured with tanshinone IIA may ameliorate Alzheimer's disease by inhibiting oxidative stress.

Methods: Sixty male Sprague-Dawley rats were randomly divided into 4 groups named Sham, Aβ25-35, mesenchymal stem cells, and mesenchymal stem cells (tanshinone IIA). The rats were treated according to different groups. The neurobehavioral performance of Sprague-Dawley rats was evaluated via Morris water maze test. Histological changes were checked via hematoxylin-eosin staining. The levels of total antioxidant activity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and malondialdehyde in hippocampus were assayed by ELISA kit. The levels of Aβ, p-tau/tau, and p-AMP-activated protein kinase/AMP-activated protein kinase in hippocampus were checked by Western blot.

Results: Our research showed that the injection of mesenchymal stem cells (tanshinone IIA) into the hippocampus alleviated learning and memory deficits and reduced hippocampal neuronal injury in the Alzheimer's disease rats. Moreover, mesenchymal stem cells (tanshinone IIA) treatment suppressed oxidative stress, attenuated Aβ accumulation reduced Tau hyperphosphorylation, and enhanced the activity of AMP-activated protein kinase in the hippocampus of the Alzheimer's disease rats. However, there were almost no significant difference between the mesenchymal stem cells and Aβ25-35 groups.

Conclusions: Mesenchymal stem cells (tanshinone IIA) transplantation may be a potential treatment for curing Alzheimer's disease, which may be related to the inhibition of oxidative stress.
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http://dx.doi.org/10.1097/WNR.0000000000001755DOI Listing
January 2022

A Comparative Study of Different Stem Cell Transplantation for Spinal Cord Injury: A Systematic Review and Network Meta-Analysis.

World Neurosurg 2021 Dec 22. Epub 2021 Dec 22.

Medical School, Hangzhou Normal University, Hangzhou, China. Electronic address:

Objective: In the present study, we evaluated the efficacy and safety of different stem cell types for spinal cord injury (SCI) therapy to determine the superior treatment of SCI.

Methods: A systematic literature search was performed using PubMed, Embase, the Cochrane Library, Web of Science, VIP, Chinese National Knowledge Infrastructure, and Wan Fang databases from initiation to January 30, 2021. A Bayesian network meta-analysis was performed using ADDIS (Aggregate Data Drug Information System) software. The PROSPERO registration number was CRD42020129635.

Results: We included 12 studies with 642 patients in the present study. A network meta-analysis revealed that bone mesenchymal stem cells (BMSCs) combined with rehabilitation training were significantly more effective than rehabilitation training alone in improving the American Spinal Injury Association (ASIA) impairment scale grade (odds ratio, 94.25; 95% confidence interval [CI], 6.71-9321.95), ASIA motor score (weighted mean difference [WMD], 6.67; 95% CI, 0.83-12.73), ASIA sensory functional score (WMD, 12.41; 95% CI, 3.42-21.72), and Barthel index (WMD, 7.24; 95% CI, 0.21-14.30). However, no statistically significant differences were observed between bone marrow mononuclear cells (MNCs) combined with rehabilitation training, umbilical cord-derived mesenchymal stem cells (UCMSCs) combined with rehabilitation training, or UCMSCs alone and rehabilitation alone for all indicators. In terms of safety, there were no serious and permanent adverse effects after transplantation of BMSCs, MNCs, or UCMSCs.

Conclusions: BMSCs plus rehabilitation might be superior to other stem cell treatments of SCI in improving the ASIA impairment scale grade, ASIA motor score, ASIA sensory functional score, and Barthel index. The therapeutic effects of UCMSCs and MNCs remain to be confirmed.
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http://dx.doi.org/10.1016/j.wneu.2021.12.035DOI Listing
December 2021

Predictive roles of D-dimer for mortality of patients with community-acquired pneumonia: a systematic review and meta-analysis.

J Bras Pneumol 2021 15;47(6):e20210072. Epub 2021 Dec 15.

. Department of Preventive Medicine, Shantou University Medical College, Shantou, Guangdong, China.

Objective: To explore the predictive roles of D-dimer for the mortality of patients with community-acquired pneumonia (CAP).

Methods: This was a systematic review and meta-analysis. We searched the following databases: PubMed, EMBASE, Web of Science, Ovid MEDLINE, and Cochrane Library from their inception to July 26, 2020. Studies exploring the relationship between blood D-dimer levels and CAP-related mortality were selected. In this meta-analysis, we calculated mortality rates, sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios.

Results: The search identified 1,073 articles, 8 of which (a total of 2,126 patients) were included in this meta-analysis. The pooled mortality rate of the overall sample was 0.10 (95% CI, 0.08-0.14). The levels of blood D-dimer in the nonsurvivors were significantly higher than those in the survivors (weighted mean difference = 1.03 mg/L [95% CI, 0.81-1.26]; p < 0.00001). The area under the summary ROC curve for the optimal cutoff value of D-dimer as a predictor of mortality was 0.848 (SE = 0.046), and the pooled negative likelihood ratio for D-dimer within the normal range was 0.24 (95% CI, 0.11-0.53).

Conclusions: Blood D-dimer might be helpful for the initial assessment of mortality risk of patients with CAP. D-dimer levels within the normal range indicate low risk of mortality. Because of the small sample size in our study, our findings should be further explored and validated in future studies with larger sample sizes.
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http://dx.doi.org/10.36416/1806-3756/e20210072DOI Listing
December 2021

Hydrogen/Deuterium Exchange Aiding Metabolite Identification in Single-Cell Nanospray High-Resolution Mass Spectrometry Analysis.

Anal Chem 2022 Jan 21;94(2):650-657. Epub 2021 Dec 21.

State Key Laboratory of Biogeology and Environmental Geology, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.

The identification of metabolites in single-cell or small-volume tissue samples using single-cell mass spectrometry (MS) is challenging. In this study, hydrogen/deuterium (H/D) exchange was combined with microsampling nanospray high-resolution mass spectrometry (HRMS) to improve the efficiency and confidence level of metabolite identification in a single cell using commercial software. A nanospray ion source showed an improved reaction depth of 8% for H/D exchange compared with an electrospray ion source. In total, 273 metabolites were identified in L. single cells by searching commercial databases. Generally, more than one candidate is given for a precursor ion by MS or tandem MS (MS) databases such as ChemSpider, MetDNA, MassBank, and mzCloud. With the help of the H/D exchange technique, the number of candidates decreased and reduction of the search space by a factor of 8 was achieved. In addition, two enzymolysis products of isoalliin, the transient intermediate and its isomer, were tracked at the single-cell level using the proposed method.
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http://dx.doi.org/10.1021/acs.analchem.1c02057DOI Listing
January 2022

Hierarchical cortical networks of "voice patches" for processing voices in human brain.

Proc Natl Acad Sci U S A 2021 Dec;118(52)

Tsinghua Laboratory of Brain and Intelligence (THBI), Tsinghua University, Beijing 100084, China;

Humans have an extraordinary ability to recognize and differentiate voices. It is yet unclear whether voices are uniquely processed in the human brain. To explore the underlying neural mechanisms of voice processing, we recorded electrocorticographic signals from intracranial electrodes in epilepsy patients while they listened to six different categories of voice and nonvoice sounds. Subregions in the temporal lobe exhibited preferences for distinct voice stimuli, which were defined as "voice patches." Latency analyses suggested a dual hierarchical organization of the voice patches. We also found that voice patches were functionally connected under both task-engaged and resting states. Furthermore, the left motor areas were coactivated and correlated with the temporal voice patches during the sound-listening task. Taken together, this work reveals hierarchical cortical networks in the human brain for processing human voices.
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http://dx.doi.org/10.1073/pnas.2113887118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8719861PMC
December 2021

ICP22/IE63 Mediated Transcriptional Regulation and Immune Evasion: Two Important Survival Strategies for Alphaherpesviruses.

Front Immunol 2021 2;12:743466. Epub 2021 Dec 2.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.

In the process of infecting the host, alphaherpesviruses have derived a series of adaptation and survival strategies, such as latent infection, autophagy and immune evasion, to survive in the host environment. Infected cell protein 22 (ICP22) or its homologue immediate early protein 63 (IE63) is a posttranslationally modified multifunctional viral regulatory protein encoded by all alphaherpesviruses. In addition to playing an important role in the efficient use of host cell RNA polymerase II, it also plays an important role in the defense process of the virus overcoming the host immune system. These two effects of ICP22/IE63 are important survival strategies for alphaherpesviruses. In this review, we summarize the complex mechanism by which the ICP22 protein regulates the transcription of alphaherpesviruses and their host genes and the mechanism by which ICP22/IE63 participates in immune escape. Reviewing these mechanisms will also help us understand the pathogenesis of alphaherpesvirus infections and provide new strategies to combat these viral infections.
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http://dx.doi.org/10.3389/fimmu.2021.743466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8674840PMC
December 2021

The LORF5 Gene Is Non-essential for Replication but Important for Duck Plague Virus Cell-to-Cell Spread Efficiently in Host Cells.

Front Microbiol 2021 2;12:744408. Epub 2021 Dec 2.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.

Duck plague virus (DPV) can cause high morbidity and mortality in many waterfowl species within the order Anseriformes. The DPV genome contains 78 open reading frames (ORFs), among which the LORF2, LORF3, LORF4, LORF5, and SORF3 genes are unique genes of avian herpesvirus. In this study, to investigate the role of this unique LORF5 gene in DPV proliferation, we generated a recombinant virus that lacks the LORF5 gene by a two-step red recombination system, which cloned the DPV Chinese virulent strain (DPV CHv) genome into a bacterial artificial chromosome (DPV CHv-BAC); the proliferation law of LORF5-deleted mutant virus on DEF cells and the effect of LORF5 gene on the life cycle stages of DPV compared with the parent strain were tested. Our data revealed that the LORF5 gene contributes to the cell-to-cell transmission of DPV but is not relevant to virus invasion, replication, assembly, and release formation. Taken together, this study sheds light on the role of the avian herpesvirus-specific gene LORF5 in the DPV proliferation life cycle. These findings lay the foundation for in-depth functional studies of the LORF5 gene in DPV or other avian herpesviruses.
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http://dx.doi.org/10.3389/fmicb.2021.744408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8674210PMC
December 2021

The lysine at position 151 of the duck hepatitis A virus 1 2C protein is critical for its NTPase activities.

Vet Microbiol 2022 Jan 7;264:109300. Epub 2021 Dec 7.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, PR China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, PR China.

The duck hepatitis A virus 1 (DHAV-1) 2C protein was predicted to be a superfamily III helicase member and includes nucleotide binding (NTB) and putative RNA helicase activity motifs. To study whether DHAV-1 2C protein has NTB activity, we expressed DHAV-1 2C protein with maltose binding protein (MBP) to solve its poor solubility in a prokaryotic expression system. We showed that the DHAV-1 2C protein has nucleoside triphosphatase (NTPase) activity by measuring the released phosphate. The NTPase of the DHAV-1 2C protein is Mg indispensable and affected by other biochemical characteristics such as Mn, Ca, Zn, Na and pH. Guanidine hydrochloride (GdnHCl), a potent inhibitor of viral RNA replication, inhibited ATPase activity of the DHAV-1 2C protein in a dose-dependent manner. Finally, we constructed three mutants to identify the key site for the ATPase activity of the DHAV-1 2C protein. These results indicate that lysine at position 151 of the DHAV-1 2C protein is very important for NTPase activity. Here, we demonstrated and partially characterized that the DHAV-1 2C protein has NTPase activity and showed that mutation of the lysine in the conserved Walker A impairs that activity. The results serve to confirm what is readily predicted from previous work on picornavirus 2C proteins. It also provides a basis for further study of the 2C protein and the function of NTPase activity on the viral life cycle.
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http://dx.doi.org/10.1016/j.vetmic.2021.109300DOI Listing
January 2022

Preliminary Study on Hepatoprotective Effect and Mechanism of (-)-Epigallocatechin-3-gallate against Acetaminophen-induced Liver Injury in Rats.

Iran J Pharm Res 2021 ;20(3):46-56

College of Biological Science and Engineering, Fuzhou University, Fuzhou 350116, China.

Antipyretic acetaminophen (APAP) is a commonly used drug that generally associates with liver injury. (-)-Epigallocatechin-3-gallate (EGCG), an active polyphenol extracted from green tea, is extensively reported to have the potential to impact a variety of human diseases. However, few studies were reported regarding the protective effect of EGCG on APAP-induced liver injury and the mechanism is still unclear. In this study, and experiments were carried out to verify the hepatoprotective effect of EGCG against APAP-induced liver injury and explore the potential mechanism. Results indicated that EGCG effectively relieved the liver injury caused by APAP, as well as APAP-induced mitochondrial dysfunction. The protective role of EGCG was not only attributed to its antioxidant capacity; but also might be related to the protective effect on hepatic mitochondrial impairment; based on that, EGCG could improve the membrane potential and activities of the respiratory chain complexes in liver mitochondria. Our study casts a new light on the mechanism of EGCG's hepatoprotective effect and suggests that EGCG has considerable potential in developing tonics for relieving APAP-induced liver injury.
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http://dx.doi.org/10.22037/ijpr.2020.112727.13918DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8653645PMC
January 2021

Inhibiting YAP in Endothelial Cells From Entering the Nucleus Attenuates Blood-Brain Barrier Damage During Ischemia-Reperfusion Injury.

Front Pharmacol 2021 26;12:777680. Epub 2021 Nov 26.

State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of TCM Evaluation and Translational Research, Department of Pharmacology of Chinese Material Medical, School of Traditional Pharmacy, China Pharmaceutical University, Nanjing, China.

Blood-brain barrier (BBB) damage is a critical event in ischemic stroke, contributing to aggravated brain damage. Endothelial cell form a major component of the BBB, but its regulation in stroke has yet to be clarified. We investigated the function of Yes-associated protein 1 (YAP) in the endothelium on BBB breakdown during cerebral ischemia/reperfusion (I/R) injury. The effects of YAP on BBB dysfunction were explored in middle cerebral artery occlusion/reperfusion (MCAO/R)-injury model mice and using brain microvascular endothelial cells (BMEC) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) injury. The degree of brain injury was estimated using staining (2,3,5-Triphenyltetrazolium chloride, hematoxylin and eosin) and the detection of cerebral blood flow. BBB breakdown was investigated by examining the leakage of Evans Blue dye and evaluating the expression of tight junction (TJ)-associated proteins and matrix metallopeptidase (MMP) 2 and 9. YAP expression was up-regulated in the nucleus of BMEC after cerebral I/R injury. Verteporfin (YAP inhibitor) down-regulated YAP expression in the nucleus and improved BBB hyperpermeability and TJ integrity disruption stimulated by cerebral I/R. YAP-targeted small interfering RNA (siRNA) exerted the same effects in BMEC cells exposed to OGD/R injury. Our findings provide new insights into the contributions made by YAP to the maintenance of BBB integrity and highlight the potential for YAP to serve as a therapeutic target to modulate BBB integrity following ischemic stroke and related cerebrovascular diseases.
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http://dx.doi.org/10.3389/fphar.2021.777680DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8662521PMC
November 2021

An automated chemiluminescent immunoassay (CLIA) detects SARS-CoV-2 neutralizing antibody levels in COVID-19 patients and vaccinees.

Int J Infect Dis 2022 Feb 10;115:116-125. Epub 2021 Dec 10.

Shenzhen Medcaptain Medical Technology Co., Ltd. Shenzhen, China.

Objectives: A specific and sensitive automated chemiluminescent immunoassay (CLIA) was developed to detect neutralizing antibody (NAb) levels. This assay can be used for the diagnosis of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, treatment and vaccine evaluation.

Methods: The SARS-CoV-2 receptor-binding domain (RBD) and a stabilized version of the spike ectodomain as antigens were detected by CLIA. Sera NAb titers and concentrations from 860 SARS-CoV-2 vaccinees, 232 SARS-CoV-2 convalescent patients and 675 healthy individuals were tested by microneutralization test (MNT) and CLIA, respectively. Mathematical models were established to evaluate the relationship between two variables in different groups.

Conclusions: With the RBD-based CLIA protocol, CLIA can be used to replace MNT to test SARS-CoV-2 NAb. Vaccine effectiveness, protectiveness and durability can be evaluated effectively by mathematical models. It is RESULTS: Analysing the relationship between NAb titers and concentrations, R for the decision-making tree was 0.870 and that of progressive linear fitting was 0.821. The receiver operating characteristic curve indicated specificity of 78.1%, sensitivity of 87.4%, cut-off value of 6.43 AU/mL and borderline range of 5.79-7.07 AU/mL for CLIA. Three-quarters (75.4%) of vaccinees were found to be NAb positive, and 5.35% vaccinees had NAb protective capability. The half-life of NAb in vaccinees was 10-11 weeks.for vaccinees to take a NAb assay periodically.
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http://dx.doi.org/10.1016/j.ijid.2021.12.316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8660141PMC
February 2022

[The Genotypes and Clinical Characteristics of Thalassemia on Children in Wuhan Region].

Zhongguo Shi Yan Xue Ye Xue Za Zhi 2021 Dec;29(6):1875-1880

Department of Pediatric Hematology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430070, Hubei Province, China,E-mail:

Objective: To investigate the genotypes and clinical characteristics of thalassemia on children in Wuhan region.

Methods: A total of 159 patients diagnosed as thalassemia in Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology from December 2017 to December 2019. The patients were retrospectively analyzed for their types of mutations, detection rates and clinical characteristics.

Results: Among the 422 samples, 159 samples were finally diagnosed as thalassemia through genetic testing, the total detection rate was 37.68%. The detection rate of α, β and αβ-thalassemia was 17.30%, 20.14% and 0.24% respectively. Among α-thalassemia, αα/-SEA was the most common one, with a composition ratio of 68.49%(50/73), followed by αα/-α3.7 (19.18%), αα/-α4.2 (6.85%) and αα/ QS (1.37%). 9 types of β-thalassemia gene mutations were detected, and the most common three mutations were IVSII-654(C→T), with a composition ratio of 40.00%, CD41-42(-TTCT) (20.00%) and CD17(A→T)(16.47%). Two novel mutations of β-thalassemia, HBB: c.92-2A>T and HBB:c.-23A>G were detected. Among all the positive patients, 134 (84.28%) were 0-3 years old, 19 (11.95%) were 4-6 years old, and 6 (3.77%) were 7 years of age or older. There were 147 patients with mild anemia (92.45%), 11 patients with moderate anemia (6.92%), and 1 patients with severe anemia (0.63%). The MCV of 94(59.12%) patients was lower than 65 fL, and that of 51(32.08%) patients was between 65 fL and 80 fL, while 14(8.81%) patients was higher than 80 fL. MCV in β-thalassemia group was lower than that in α-thalassemia group, and the difference showed statistically significant (P<0.05).

Conclusion: The genotypes of thalassemia in children in Wuhan area are diverse, and most of them are mild thalassemia, and diagnosed under 3 years old. Children with β-thalassemia have smaller red blood cell volumes than those with α-thalassemia.
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http://dx.doi.org/10.19746/j.cnki.issn.1009-2137.2021.06.031DOI Listing
December 2021

DHAV-1 Blocks the Signaling Pathway Upstream of Type I Interferon by Inhibiting the Interferon Regulatory Factor 7 Protein.

Front Microbiol 2021 12;12:700434. Epub 2021 Nov 12.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.

Duck hepatitis A virus (DHAV), which mainly infects 1- to 4-week-old ducklings, has a fatality rate of 95% and poses a huge economic threat to the duck industry. However, the mechanism by which DHAV-1 regulates the immune response of host cells is rarely reported. This study examined whether DHAV-1 contains a viral protein that can regulate the innate immunity of host cells and its specific regulatory mechanism, further exploring the mechanism by which DHAV-1 resists the host immune response. In the study, the dual-luciferase reporter gene system was used to screen the viral protein that regulates the host innate immunity and the target of this viral protein. The results indicate that the DHAV-1 3C protein inhibits the pathway upstream of interferon (IFN)-β by targeting the interferon regulatory factor 7 (IRF7) protein. In addition, we found that the 3C protein inhibits the nuclear translocation of the IRF7 protein. Further experiments showed that the 3C protein interacts with the IRF7 protein through its N-terminus and that the 3C protein degrades the IRF7 protein in a caspase 3-dependent manner, thereby inhibiting the IFN-β-mediated antiviral response to promote the replication of DHAV-1. The results of this study are expected to serve as a reference for elucidating the mechanisms of DHAV-1 infection and pathogenicity.
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http://dx.doi.org/10.3389/fmicb.2021.700434DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8633874PMC
November 2021

Development of an indirect ELISA method based on the VP4 protein for detection antibody against duck hepatitis A virus type 1.

J Virol Methods 2022 Feb 30;300:114393. Epub 2021 Nov 30.

Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, PR China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan, 611130, PR China.

In Picornavirus, the VP4 gene is located inside the viral capsid, but the antibodies it produces have neutralizing activity. At the same time, we know that the VP4 gene is relatively conserved among the four structural proteins, which makes the usage VP4 protein-based antigen potentially meaningful. Therefore, we used purified duck hepatitis A virus type 1 (DHVA-1) recombinant VP4 protein as the coating antigen to establish an indirect method. The optimal antigen, serum and enzyme-labeled antibody dilutions were 1:400 (3.375 μg/mL), 1:80 and 1:1600, respectively. The optimal blocking buffer was 1% skimmed milk powder. The cutoff value was determined to be 0.203, and the analytical sensitivity was 1:1600. The established ELISA method has good specificity, repeatability and sensitivity. It has a high coincidence rate of 70.8 % with the DHVA-1 as the coating antigen. So, it can be used for the detection of DHAV-1 serum antibodies.
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http://dx.doi.org/10.1016/j.jviromet.2021.114393DOI Listing
February 2022

A pilot study of the association between leukoaraiosis and cerebral atherosclerosis using synthetic magnetic resonance imaging.

Acta Radiol 2021 Dec 1:2841851211044970. Epub 2021 Dec 1.

Radiology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, PR China.

Background: Leukoaraiosis is a type of lesion characterized by tissue rarefaction or myelin pallor resulting from axons loss and gliosis. Synthetic magnetic resonance imaging (MRI) could yield quantitative T1, T2, proton density (PD) values of leukoaraiosis in addition to information on the volume of the lesion.

Purpose: To investigate the feasibility of quantifying leukoaraiosis using synthetic MRI and to explore the association between leukoaraiosis and cerebral small vascular diseases and cerebral atherosclerosis.

Material And Methods: Patients with acute ischemic stroke were enrolled in this study. All participants underwent a conventional T2-weighted image, brain volume, CUBE fluid attenuated inversion recovery, and synthetic MRI acquisition using a 3.0-T MR system. A time-of-flight magnetic resonance angiography was also obtained. We evaluated the T1, T2, PD values and leukoaraiosis volume.

Results: Analysis of the leukoaraiosis volume ratios demonstrated a positive association with T2 values, a negative association with T1 values, and no association with PD values. Leukoaraiosis volume ratios were independently correlated with age ( < 0.001), lacunes ( = 0.022), and cerebral microbleeds ( = 0.010). A statistical association was found between both age ( < 0.001) and lacunes ( = 0.047) and leukoaraiosis T2 values.

Conclusion: Synthetic MRI may enhance the evaluation of leukoaraiosis, in addition to providing information on its volume. Leukoaraiosis may represent a type of cerebral small vascular disease rather than cerebral atherosclerosis and may share the same pathological mechanism as lacunes and cerebral microbleeds.
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http://dx.doi.org/10.1177/02841851211044970DOI Listing
December 2021

Sorting nexins: role in the regulation of blood pressure.

FEBS J 2021 Nov 30. Epub 2021 Nov 30.

Department of Clinical Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China.

Sorting nexins (SNXs) are a family of proteins that regulate cellular cargo sorting and trafficking, maintain intracellular protein homeostasis, and participate in intracellular signaling. SNXs are also important in the regulation of blood pressure via several mechanisms. Aberrant expression and dysfunction of SNXs participate in the dysregulation of blood pressure. Genetic studies show a correlation between SNX gene variants and the response to antihypertensive drugs. In this review, we summarize the progress in SNX-mediated regulation of blood pressure, discuss the potential role of SNXs in the pathophysiology and treatment of hypertension, and propose novel strategies for the medical therapy of hypertension.
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http://dx.doi.org/10.1111/febs.16305DOI Listing
November 2021

Toward understanding submersed macrophyte Vallisneria natans-microbe partnerships to improve remediation potential for PAH-contaminated sediment.

J Hazard Mater 2022 03 22;425:127767. Epub 2021 Nov 22.

Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 210096, China.

Rhizodegradation using submersed macrophytes Vallisneria natans (V. natans) is a promising biotechnology with the potential to restore polycyclic aromatic hydrocarbon (PAH)-contaminated sediments. However, how different sediment types influence the rhizoremediation outcome and the characterization of microbial community along the sediment-V. natans continuum is poorly understood. Here, we collect V. natans, sediments and overlying water from two types of vegetation zones with different levels of PAHs pollutions and set up sediment microcosms for phytoremediation tests. V. natans presence was particularly useful for PAHs remediation in the highly contaminated sites and had a significant effect on PAHs rhizodegradation and microbial communities, especially rhizosphere sediments. The structural composition of microbial communities along the sediment-plant continuum was shaped predominantly by compartment niche of V. natans. Moreover, selective enrichment of specific microbial taxa like Herbaspirillum (relative abundance = 94.80%) in endosphere of V. natans was observed. Herbaspirillum could use PAH as carbon source and promote the growth of plants. In the highly contaminated sediment, V. natans could recruit these bacteria for toxicant degradation into the root interior. Thus, understanding the complex V. natans-microbe interactions could help set up novel decontamination strategies based on the rhizosphere and root interior interactions between plants and their microbial associates.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127767DOI Listing
March 2022

Aberrant expression of SPAG6 may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative myeloproliferative neoplasms.

Oncol Lett 2022 Jan 10;23(1):10. Epub 2021 Nov 10.

Department of Hematology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400042, P.R. China.

Sperm-associated antigen 6 (SPAG6) is a newly identified cancer-testis antigen that has been revealed to contribute to the occurrence and development of various types of human cancer, such as ovarian, bladder, breast and lung cancer. However, to the best of our knowledge, the expression levels of SPAG6 in breakpoint cluster region (BCR)/ABL1-negative myeloproliferative neoplasms (MPNs) have not been investigated previously. Using reverse transcription-quantitative PCR and different tissue staining techniques, the present study revealed that SPAG6 was expressed by MPN cells, both at the mRNA and protein levels, and that nucleated erythroid precursors and megakaryocytes expressed the highest levels of SPAG6. In addition, SPAG6, which is known as a microtubule-associated protein, was found to exhibit nucleic, cytoplasmic or both cytoplasmic and nucleic subcellular localization patterns within the same patient or cell type; however, it did not always co-localize with β-tubulin. Furthermore, SPAG6 expression was revealed to be associated with fewer splenomegaly [P=0.015 for polycythemia vera (PV) and essential thrombocythemia (ET); and P=0.012 for primary myelofibrosis (PMF)] and myelofibrosis events (P=0.014 for PV and ET; and P=0.004 for PMF). In patients with PMF, upregulated expression levels of SPAG6 were also found to be associated with lower white blood cell counts (P=0.042) and lactate dehydrogenase levels (P=0.012), and higher hemoglobin levels (P=0.031) and platelet counts (P=0.025). In addition, the receiver operating characteristic curve analysis indicated that SPAG6 may be a potential biomarker for distinguishing MPN cases from healthy individuals. In conclusion, to the best of our knowledge, the present study is the first to report that aberrant SPAG6 expression may affect the disease phenotype and serve as a tumor biomarker in BCR/ABL1-negative MPNs.
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http://dx.doi.org/10.3892/ol.2021.13128DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8607346PMC
January 2022

Unexpected high retention of N-labeled nitrogen in a tropical legume forest under long-term nitrogen enrichment.

Glob Chang Biol 2022 Feb 28;28(4):1529-1543. Epub 2021 Nov 28.

Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.

The responses of forests to nitrogen (N) deposition largely depend on the fates of deposited N within the ecosystem. Nitrogen-fixing legume trees widely occur in terrestrial forests, but the fates of deposited N in legume-dominated forests remain unclear, which limit a global evaluation of N deposition impacts and feedbacks on carbon sequestration. Here, we performed the first ecosystem-scale N labeling experiment in a typical legume-dominated forest as well as in a nearby non-legume forest to determine the fates of N deposition between two different forest types and to explore their underlying mechanisms. The N was sprayed bimonthly for 1 year to the forest floor in control and N addition (50 kg N ha  year for 10 years) plots in both forests. We unexpectedly found a strong capacity of the legume forest to retain deposited N, with 75 ± 5% labeled N recovered in plants and soils, which was higher than that in the non-legume forest (56 ± 4%). The higher N recovery in legume forest was mainly driven by uptake by the legume trees, in which N recovery was approximately 15% more than that in the nearby non-legume trees. This indicates higher N-demand by the legume than non-legume trees. Mineral soil was the major sink for deposited N, with 39 ± 4% and 34 ± 3% labeled N retained in the legume and non-legume forests, respectively. Moreover, N addition did not significantly change the N recovery patterns of both forests. Overall, these findings indicate that legume-dominated forests act as a strong sink for deposited N regardless of high soil N availability under long-term atmospheric N deposition, which suggest a necessity to incorporate legume-dominated forests into N-cycling models of Earth systems to improve the understanding and prediction of terrestrial N budgets and the global N deposition effects.
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http://dx.doi.org/10.1111/gcb.16005DOI Listing
February 2022

Characterization of metabolic pathways for biosynthesis of the flavor compound 3-methylbutanal by Lactococcus lactis.

J Dairy Sci 2022 Jan 28;105(1):97-108. Epub 2021 Oct 28.

School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai 201418, P.R. China. Electronic address:

3-Methylbutanal is a key volatile compound that imparts a nutty flavor to Cheddar cheese. Lactococcus lactis has been successfully applied as a starter to increase the level of 3-methylbutanal produced during the ripening of cheese. However, the mechanism of action and genetic diversity of this bacterium for 3-methylbutanal biosynthesis remains unclear. In this study, we investigated the association between the L. lactis genotype and phenotype in the biosynthesis of 3-methylbutanal via both direct and indirect pathways. Fourteen strains of L. lactis were screened for the capacity to produce 3-methylbutanal, and strain 408 (>140 μM) produced the highest among all tested strains, which exhibited both α-keto acid decarboxylase and α-ketoacid dehydrogenase activities. Furthermore, the results of a sodium meta-arsenite inhibition experiment showed that the 3-methylbutanal-producing capacities of each strain declined to various degrees. The kdcA gene, which encodes the direct pathway component α-ketoacid decarboxylase, was detected in 4 of the 14 strains, of which only strain 408 contained the full-length gene. We then characterized the genes associated with the indirect pathway by detecting the expression levels of the pdh gene cluster, ack, and pta, which were expressed at relatively higher levels in a high-yield strain than in a low-yield strain. As a result, these L. lactis strains were divided into 3 categories according to gene diversity, gene expression, and 3-methylbutanal production. The results of this study refine our knowledge of the genetic determinants of 3-methylbutanal biosynthesis in L. lactis and explain the effect of both synthesis pathways on 3-methylbutanal production.
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http://dx.doi.org/10.3168/jds.2021-20779DOI Listing
January 2022

DNA barcode reference library construction and genetic diversity and structure analysis of Lour. (Zingiberaceae) populations in Guangdong Province.

PeerJ 2021 20;9:e12325. Epub 2021 Oct 20.

The Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, China.

Background: Lour. is the plant that produces the famous traditional Chinese medicine Amomi Fructus. Frequent habitat destruction seriously threatens germplasm resources. Genetic diversity is very important to the optimization of germplasm resources and population protection, but the range of inherited traits within is unclear. In this study, we analyzed the genetic diversity and genetic structures of populations in Guangdong and constructed a local reference DNA barcode library as a resource for conservation efforts.

Methods: DNA barcoding and Inter-Simple Sequence Repeat (ISSR) markers were used to investigate the population genetics of Five universal DNA barcodes were amplified and used in the construction of a DNA barcode reference library. Parameters including percentage of polymorphic sites (PPB), number of alleles (Na), effective number of alleles (Ne), Nei's gene diversity index (H), and Shannon's polymorphism information index (I) were calculated for the assessment of genetic diversity. Genetic structure was revealed by measuring Nei's gene differentiation coefficient (Gst), total population genetic diversity (Ht), intra-group genetic diversity (Hs), and gene flow (Nm). Analysis of molecular variance (AMOVA), Mantel tests, unweighted pair-group method with arithmetic mean (UPGMA) dendrogram, and principal co-ordinates (PCoA) analysis were used to elucidate the genetic differentiation and relationship among populations.

Results: A total of 531 sequences were obtained from the five DNA barcodes with no variable sites from any of the barcode sequences. A total of 66 ISSR bands were generated from populations using the selected six ISSR primers; 56 bands, 84.85% for all the seven populations were polymorphic. The populations showed high genetic diversity ( = 0.3281,  = 0.4895), whereas the gene flow was weak (Nm = 0.6143). Gst (0.4487) and AMOVA analysis indicated that there is obvious genetic differentiation among populations and more genetic variations existed within each population. The genetic relationship of each population was relatively close as the genetic distances were between 0.0844 and 0.3347.
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http://dx.doi.org/10.7717/peerj.12325DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8541303PMC
October 2021
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