Publications by authors named "Rong Fan"

509 Publications

Passivation of pyrite for reduced rates of acid and metalliferous drainage using readily available mineralogic and organic carbon resources: A laboratory mine waste study.

Chemosphere 2021 Jun 26;285:131330. Epub 2021 Jun 26.

Blue Minerals Consultancy, Wattle Grove, TAS, 7109, Australia. Electronic address:

Acid and metalliferous drainage (AMD) is a major environmental issue resulting largely from exposure to weathering of mine wastes containing pyrite (FeS). At-source strategies to reduce the rate of formation of AMD have potential to be more cost-effective and sustainable than post-generation downstream treatments. The objective of this study was to examine the efficacy of geochemical and microbial treatments for at-source control through pyrite surface passivation. Six kinetic leach columns (KLCs), using a mine waste containing 3.8 wt% pyrite, were subjected to various treatments: 1) untreated, 2) blended calcite, and applications of 3) calcite-saturated water, 4) lime-saturated water followed by calcite-saturated water, 5) biosolids extract water (providing a source of organic carbon to promote microbial growth) and 6) biosolids extract in calcite-saturated water. The untreated KLC leachate pH was on average 5.7 for the first 12 weeks, followed by a gradual decrease to pH 4.5 at week 52. This slow pH decrease is attributed to neutralisation released upon Mg-siderite dissolution. The leachate pH from all treated KLCs was near-neutral at the end of the tests. Pyrite was surface-passivated and leaching supressed by all treatments except for calcite-saturated water. Leaching of Mn and Zn from the untreated waste identified the potential for adverse environmental impact. No evidence was found for surface passivation of Zn- or Mn-containing minerals in the treated KLCs. Blended calcite addition and lime-saturated water followed by calcite-saturated water were most effective at reducing release of Zn and Mn, likely due to precipitation as hydroxides/carbonates.
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http://dx.doi.org/10.1016/j.chemosphere.2021.131330DOI Listing
June 2021

Wedelolactone alleviates acute pancreatitis and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis.

Free Radic Biol Med 2021 Jul 8;173:29-40. Epub 2021 Jul 8.

Department of Hepatobiliary and Pancreatic Surgery, The Second Hospital of Dalian Medical University, Dalian, Liaoning, PR China. Electronic address:

Acute pancreatitis (AP) is an inflammatory disorder associated with multiple organ failure. Pyroptosis and ferroptosis are two newly recognized cell death, and whether pyroptosis and ferroptosis are involved in AP remain largely elusive. The nature compound Wedelolactone (Wed) exhibits strong anti-inflammatory and antioxidant activities, the present study aims to investigate the effect of Wed on AP and unravel whether Wed could protect against AP and relevant lung injury against pyroptosis and ferroptosis. Our results showed that the pyroptosis inhibitor disulfiram or ferroptosis inhibitor ferrostatin-1 significantly alleviated AP and associated lung injury in the taurocholate or caerulein-induced murine AP model. Administration with Wed ameliorated AP and lung injury as evidenced by improved pathological injuries, reduced serum pancreatic digestive enzymes, and proinflammatory cytokines. The in vivo and in vitro data demonstrated that Wed broadly inhibited caspase1/caspase11 activation, reduced mature interleukin-1β (IL-1β) and N-terminal domain of gasdermin D (GSDMD-N) level. The oxidative stress and lipid peroxidation were also suppressed along with the up-regulation of the ferroptosis antagonism marker glutathione peroxidase-4 (GPX4) in Wed treatment group. Wed promoted the transcriptional activity and the selenium sensitivity of GPX4. Moreover, the protective effects of Wed in caerulein-stimulated pancreatic acinar cells were markedly abrogated by the down-regulation of GPX4. Collectively, our data suggest that pyroptosis and ferroptosis play crucial roles in AP. Wed mitigated AP and associated lung injury via GPX4 mediated suppression of pyroptosis and ferroptosis.
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http://dx.doi.org/10.1016/j.freeradbiomed.2021.07.009DOI Listing
July 2021

Association of central obesity with hepatocellular carcinoma in patients with chronic hepatitis B receiving antiviral therapy.

Aliment Pharmacol Ther 2021 Aug 22;54(3):329-338. Epub 2021 Jun 22.

Guangzhou, China.

Background: Obesity is typically associated with metabolic dysfunction, but its impact on hepatocellular carcinoma (HCC) remains unclear in patients with chronic hepatitis B (CHB).

Aim: To study the effect of obesity on HCC development in patients with CHB receiving antiviral therapy.

Methods: We included patients from a Chinese multicentre, prospective, observational, treated CHB cohort in this study. General obesity was evaluated by body-mass index (BMI). Central obesity was evaluated by waist circumference, waist-to-hip ratio and waist-to-height ratio.

Results: A total of 5754 nucleos(t)ide analogue treated patients were enrolled in the analysis. The 5-year cumulative incidence of HCC was 2.9%. Waist-to-height ratio performed better in predicting HCC development than BMI, waist circumference or waist-to-hip ratio. Patients with central obesity (defined as waist-to-height ratio >0.5) had significantly higher 5-year incidence of HCC than those without central obesity in the overall population (3.9% vs 2.1%, hazard ratio [HR]: 2.06, P = 0.0001) and 745 propensity score matched pairs (4.7% vs 2.3%, HR: 2.04, P = 0.026), respectively. Besides cirrhosis status and aMAP HCC risk score, central obesity was also independently associated with HCC risk (HR: 1.63, P = 0.013). Waist-to-height ratio gain within 1 year was associated with a significantly higher HCC risk with an adjusted HR value of 1.88 (95% confidence interval: 1.12-3.13, P = 0.017).

Conclusions: Central obesity, evaluated by the waist-to-height ratio, was associated with a twofold increase in HCC risk among CHB patients receiving antiviral treatment, highlighting the important role of abnormal metabolic function in the progression of liver disease.
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http://dx.doi.org/10.1111/apt.16469DOI Listing
August 2021

Integrated bioinformatics analysis and screening of hub genes in papillary thyroid carcinoma.

PLoS One 2021 11;16(6):e0251962. Epub 2021 Jun 11.

Department of Operational Medicine, Tianjin Institute of Environmental and Operational Medicine, Tianjin, PR China.

Background: With the increasing incidence of papillary thyroid carcinoma (PTC), PTC continues to garner attention worldwide; however its pathogenesis remains to be elucidated. The purpose of this study was to explore key biomarkers and potential new therapeutic targets for, PTC.

Methods: GEO2R and Venn online software were used for screening of differentially expressed genes. Hub genes were screened via STRING and Cytoscape, followed by Gene Ontology and KEGG enrichment analysis. Finally, survival analysis and expression validation were performed using the UALCAN online software and immunohistochemistry.

Results: We identified 334 consistently differentially expressed genes (DEGs) comprising 136 upregulated and 198 downregulated genes. Gene Ontology enrichment analysis results suggested that the DEGs were mainly enriched in cancer-related pathways and functions. PPI network visualization was performed and 17 upregulated and 13 downregulated DEGs were selected. Finally, the expression verification and overall survival analysis conducted using the Gene Expression Profiling Interactive Analysis Tool (GEPIA) and UALCAN showed that LPAR5, TFPI, and ENTPD1 were associated with the development of PTC and the prognosis of PTC patients, and the expression of LPAR5, TFPI and ENTPD1 was verified using a tissue chip.

Conclusions: In summary, the hub genes and pathways identified in the present study not only provide information for the development of new biomarkers for PTC but will also be useful for elucidation of the pathogenesis of PTC.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0251962PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8195368PMC
June 2021

Influence of Ceramic Membrane Surface Characteristics on the Flux Behavior of a Complex Fermentation Broth.

Membranes (Basel) 2021 May 28;11(6). Epub 2021 May 28.

Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, 35390 Giessen, Germany.

The valorization of agro-industrial residues using yeasts as biocatalysts requires efficient methods for biomass separation. Filtration with ceramic membranes is suitable for this task, however, the challenge of flux decline and the unavoidable cleaning must be taken into account. We investigated the filtration of fermentation broth and its components using tubular microfiltration and ultrafiltration membranes, and hollow-fiber ultrafiltration membranes, with cut-offs of 30 and 200 nm. The steady-state flux was limited by fouling under comparable wall shear stress conditions but increased when the wall shear stress was higher. Single-component filtration with two 30 nm tubular ultrafiltration membranes, whose average surface roughness ranged from 1.0 to 3.9 µm, showed that smoother surfaces experience less biomass fouling under more intense hydrodynamic conditions. Furthermore, we showed experimentally and by scanning electron microscopy in filtration with 30 nm tubular membranes that the thickness of the first separation layer is responsible for the degree of irreversible resistance caused by the deposition of organic material in the membrane pores. The thickness of this layer should therefore be minimized without compromising mechanical stability.
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http://dx.doi.org/10.3390/membranes11060402DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8229547PMC
May 2021

Gualou Xiebai Banxia decoction ameliorates Poloxamer 407-induced hyperlipidemia.

Biosci Rep 2021 Jun;41(6)

Department of Operational Medicinal Research, Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China.

Ethnopharmacological Relevance: Gualou Xiebai Banxia (GLXBBX) decoction is a well-known traditional Chinese herbal formula that was first discussed in the Synopsis of the Golden Chamber by Zhang Zhongjing in the Eastern Han Dynasty. In traditional Chinese medicine, GLXBBX is commonly prescribed to treat cardiovascular diseases, such as coronary heart disease and atherosclerosis.

Objective: The present study aimed to examine GLXBBX's preventative capacity and elucidate the potential molecular mechanism of Poloxamer 407 (P407)-induced hyperlipidemia in rats.

Materials And Methods: Both the control and model groups received pure water, and the test group also received a GLXBBX decoction. For each administration, 3 ml of the solution was administered orally. To establish hyperlipidemia, a solution mixed with 0.25 g/kg P407 dissolved in 0.9% normal saline was injected slowly into the abdominal cavity. At the end of the study, the rats' plasma lipid levels were calculated using an automatic biochemical analyzer to evaluate the preventative capability of the GLXBBX decoction, and the serum and liver of the rats were collected.

Results: The GLXBBX decoction significantly improved P407-induced hyperlipidemia, including increased plasma triglycerides (TGs), aspartate aminotransferase (AST) elevation, and lipid accumulation. Moreover, GLXBBX decoction treatment increased lipoprotein lipase (LPL) activity and mRNA expression of LPL. Furthermore, GLXBBX significantly suppressed the mRNA expression of stearoyl-CoA desaturase (SCD1).

Conclusion: GLXBBX significantly improved P407-induced hyperlipidemia, which may have been related to enhanced LPL activity, increased LPL mRNA expression, and decreased mRNA expression of SCD1.
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http://dx.doi.org/10.1042/BSR20204216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8204229PMC
June 2021

Spatial multi-omics sequencing for fixed tissue via DBiT-seq.

STAR Protoc 2021 Jun 11;2(2):100532. Epub 2021 May 11.

Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA.

This protocol describes the use of the deterministic barcoding in tissue for spatial omics sequencing platform to construct a multi-omics atlas on fixed frozen tissue samples. This approach uses a microfluidic-based method to introduce combinatorial DNA oligo barcodes directly to the cells in a tissue section fixed on a glass slide. This technique does not directly resolve single cells but can achieve a near-single-cell resolution for spatial transcriptomics and spatial analysis of a targeted panel of proteins. For complete details on the use and execution of this protocol, please refer to Liu et al. (2020).
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http://dx.doi.org/10.1016/j.xpro.2021.100532DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8132129PMC
June 2021

Aroma and catechin profile and in vitro antioxidant activity of green tea infusion as affected by submerged fermentation with Wolfiporia cocos (Fu Ling).

Food Chem 2021 Nov 12;361:130065. Epub 2021 May 12.

University of Hohenheim, Institute of Food Science and Biotechnology, Department of Flavor Chemistry, Fruwirthstraße 12, 70599 Stuttgart, Germany. Electronic address:

In response to the increasing interest of western consumers in high antioxidant activity of green tea but their low acceptance of its green odor, we employed a new starter culture, Wolfiporia cocos to tune flavor of green tea infusion. After submerged fermentation for 17 h, W. cocos changed the characteristic green odor to an attractive floral, jasmine-like, and slightly citrus-like flavor while preserving most of in vitro antioxidant activity. By application of mSBSE-GC-MS-O combined with sensorial tests, the formed pleasant aroma was mainly attributed to methyl anthranilate (OAV 802), linalool (OAV 190), 2-phenylethanol (OAV165), and geraniol (OAV 118). Concurrently, the catechin profile determined by UHPLC-MS showed diverse reduction rates (10-50%) for the individual catechins after fermentation. Nevertheless, up to 80% of in vitro antioxidant activity in DPPH assay was preserved. Overall, our findings provide an innovative approach to naturally flavor green tea while retaining the antioxidant activity.
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http://dx.doi.org/10.1016/j.foodchem.2021.130065DOI Listing
November 2021

κ-opioid receptor stimulation alleviates rat vascular smooth muscle cell calcification via PFKFB3-lactate signaling.

Aging (Albany NY) 2021 05 20;13(10):14355-14371. Epub 2021 May 20.

Department of Physiology and Pathophysiology, National Key Discipline of Cell Biology, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.

In the present study, the effects and mechanism of action of U50,488H (a selective κ-opioid receptor agonist) on calcification of rat vascular smooth muscle cells (VSMCs) induced by β-glycerophosphate (β-GP) were investigated. VSMCs were isolated and cultured in traditional FBS-based media. A calcification model was established in VSMCs under hyperphosphatemia and intracellular calcium contents. Alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and lactate were detected in cell culture supernatants before and after treatment. Alizarin red staining was used to detect the degree of calcification of VSMCs. Expression levels of key molecules of osteogenic markers, fructose-2,6-biphosphatase 3 (PFKFB3), and proline hydroxylase 2 (PHD2), were determined using western blotting. Further, vascular calcification was induced by vitamin plus nicotine in rats and isolated thoracic aortas, calcium concentration was assessed in rat aortic rings . We demonstrated that U50,488H inhibited VSMC calcification in a concentration-dependent manner. Moreover, U50,488H significantly inhibited osteogenic differentiation and ALP activity in VSMCs pretreated with β-GP. Further studies confirmed that PFKFB3 expression, LDH level, and lactate content significantly increased during calcification of VSMCs; U50,488H reversed these changes. PHD2 expression showed the opposite trend compared to PFKFB3 expression. nor-BNI or 3-PO abolished U50,488H protective effects. Besides, U50,488H inhibited VSMC calcification in rat aortic rings . Collectively, our experiments show that κ-opioid receptor activation inhibits VSMC calcification by reducing PFKFB3 expression and lactate content, providing a potential drug target and strategy for the clinical treatment of vascular calcification.
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http://dx.doi.org/10.18632/aging.203050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8202865PMC
May 2021

Single-cell multiomics dissection of basal and antigen-specific activation states of CD19-targeted CAR T cells.

J Immunother Cancer 2021 May;9(5)

Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA

Background: Autologous T cells engineered to express a chimeric antigen receptor (CAR) specific for CD19 molecule have transformed the therapeutic landscape in patients with highly refractory leukemia and lymphoma, and the use of donor-generated allogeneic CAR T is paving the way for further breakthroughs in the treatment of cancer. However, it remains unknown how the intrinsic heterogeneities of these engineered cells mediate therapeutic efficacy and whether allogeneic products match the effectiveness of autologous therapies.

Methods: Using single-cell mRNA sequencing in conjunction with CITE-seq, we performed multiomics characterization of CAR T cells generated from healthy donor and patients with acute lymphoblastic leukemia. CAR T cells used in this study were manufactured at the University of Pennsylvania through lentiviral transduction with a CD19-4-1BB-CD3ζ construct. Besides the baseline condition, we engineered NIH-3T3 cells with human CD19 or mesothelin expression to conduct ex vivo antigen-specific or non-antigen stimulation of CAR T cells through 6-hour coculture at a 1:1 ratio.

Results: We delineated the global cellular and molecular CAR T landscape and identified that transcriptional CAR tonic signaling was regulated by a mixture of early activation, exhaustion signatures, and cytotoxic activities. On CD19 stimulation, we illuminated the disparities of CAR T cells derived from different origins and found that donor CAR T had more pronounced activation level in correlation with the upregulation of major histocompatibility complex class II genes compared with patient CAR T cells. This finding was independently validated in additional datasets from literature. Furthermore, GM-CSF() expression was found to be associated with functional gene productions, but it induced little impact on the CAR T activation.

Conclusions: Through integrated multiomics profiling and unbiased canonical pathway analyses, our results unveil heterogeneities in the transcriptional, phenotypic, functional, and metabolic profiles of donor and patient CAR T cells, providing mechanistic basis for ameliorating clinical outcomes and developing next-generation 'off- the-shelf' allogeneic products.
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http://dx.doi.org/10.1136/jitc-2020-002328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8137188PMC
May 2021

Single-cell Analysis Technologies for Immuno-oncology Research: from Mechanistic Delineation to Biomarker Discovery.

Genomics Proteomics Bioinformatics 2021 May 14. Epub 2021 May 14.

Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Yale Stem Cell Center and Yale Cancer Center, Yale School of Medicine, New Haven, CT 06511, USA; Human and Translational Immunology, Yale School of Medicine, New Haven, CT 06511, USA. Electronic address:

The successes with immune checkpoint blockade (ICB) and chimeric antigen receptor (CAR)-T-cell therapy in treating multiple cancer types have established immunotherapy as a powerful curative option for patients with advanced cancers. Unfortunately, many patients do not derive benefit or long-term responses, highlighting a pressing need to perform complete investigation of the underlying mechanisms and the immunotherapy-induced tumor regression or rejection. In recent years, a large number of single-cell technologies have leveraged advances in characterizing immune system, profiling tumor microenvironment, and identifying cellular heterogeneity, which establish the foundations for lifting the veil on the comprehensive crosstalk between cancer and immune system during immunotherapies. In this review, we introduce the applications of the most widely used single-cell technologies in furthering our understanding of immunotherapies in terms of underlying mechanisms and their association with therapeutic outcomes. We also discuss how single-cell analyses help to deliver new insights into biomarker discovery to predict patient response rate, monitor acquired resistance, and support prophylactic strategy development for toxicity management. Finally, we provide an overview of applying cutting-edge single-cell spatial-omics to point out the heterogeneity of tumor-immune interactions at higher level that can ultimately guide to the rational design of next-generation immunotherapies.
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http://dx.doi.org/10.1016/j.gpb.2021.02.004DOI Listing
May 2021

The Landscape of Cell-Free HBV Integrations and Mutations in Cirrhosis and Hepatocellular Carcinoma Patients.

Clin Cancer Res 2021 Jul 4;27(13):3772-3783. Epub 2021 May 4.

Berry Oncology Corporation. Beijing, PR China.

Purpose: Intratumoral hepatitis B virus (HBV) integrations and mutations are related to hepatocellular carcinoma (HCC) progression. Circulating cell-free DNA (cfDNA) has shown itself as a powerful noninvasive biomarker for cancer. However, the HBV integration and mutation landscape on cfDNA remains unclear.

Experimental Design: A cSMART (Circulating Single-Molecule Amplification and Resequencing Technology)-based method (SIM) was developed to simultaneously investigate HBV integration and mutation landscapes on cfDNA with HBV-specific primers covering the whole HBV genome. Patients with HCC ( = 481) and liver cirrhosis (LC; = 517) were recruited in the study.

Results: A total of 6,861 integration breakpoints including and were discovered in HCC cfDNA, more than in LC. The concentration of circulating tumor DNA (ctDNA) was positively correlated with the detection rate of these integration hotspots and total HBV integration events in cfDNA. To track the origin of HBV integrations in cfDNA, whole-genome sequencing (WGS) was performed on their paired tumor tissues. The paired comparison of WGS data from tumor tissues and SIM data from cfDNA confirmed most recurrent integration events in cfDNA originated from tumor tissue. The mutational landscape across the whole HBV genome was first generated for both HBV genotype C and B. A region from nt1100 to nt1500 containing multiple HCC risk mutation sites (OR > 1) was identified as a potential HCC-related mutational hot zone.

Conclusions: Our study provides an in-depth delineation of HBV integration/mutation landscapes at cfDNA level and did a comparative analysis with their paired tissues. These findings shed light on the possibilities of noninvasive detection of virus insertion/mutation.
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http://dx.doi.org/10.1158/1078-0432.CCR-21-0002DOI Listing
July 2021

Clinical Characteristics of Chinese Male Patients with Aquaporin-4 Antibody-Positive Late-Onset Neuromyelitis Optica Spectrum Disorder.

Neuroimmunomodulation 2021 4;28(2):61-67. Epub 2021 May 4.

Department of Neurology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

Background And Objective: Limited studies are available for male patients with anti-aquaporin-4 antibody (AQP4-Ab)-positive late-onset neuromyelitis optica spectrum disease (LONMOSD). The aim of this study was to investigate the clinical characteristics of Chinese male patients with AQP4-Ab-positive LONMOSD.

Methods: We retrospectively reviewed the medical records of 12 male patients with LONMOSD, 16 male patients with early-onset NMOSD (EONMOSD), and 64 female patients with LONMOSD. These enrolled patients were classified according to the age of onset: LONMOSD (≥50 years of age at onset) versus EONMOSD (<50 years of age at onset). Clinical characteristics and magnetic resonance imaging (MRI) findings were collected. All included patients were positive for AQP4 antibody.

Results: Compared with female LONMOSD patients, male LONMOSD patients had less frequent transverse myelitis (TM) at onset (8.33 vs. 53.13%, p = 0.004) and lower Expanded Disability Status Scale (EDSS) scores (median 1 vs. 4, p = 0.036). Compared with male EONMOSD patients, male LONMOSD patients had a shorter time from onset to diagnosis (0.85 months vs. 6.00 months, p = 0.04).

Conclusion: Less common TM at onset, less disease severity, and shorter time from onset to diagnosis probably occur in male LONMOSD patients.
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http://dx.doi.org/10.1159/000515555DOI Listing
May 2021

Single-cell dynamics of chromatin activity during cell lineage differentiation in Caenorhabditis elegans embryos.

Mol Syst Biol 2021 04;17(4):e10075

State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.

Elucidating the chromatin dynamics that orchestrate embryogenesis is a fundamental question in developmental biology. Here, we exploit position effects on expression as an indicator of chromatin activity and infer the chromatin activity landscape in every lineaged cell during Caenorhabditis elegans early embryogenesis. Systems-level analyses reveal that chromatin activity distinguishes cellular states and correlates with fate patterning in the early embryos. As cell lineage unfolds, chromatin activity diversifies in a lineage-dependent manner, with switch-like changes accompanying anterior-posterior fate asymmetry and characteristic landscapes being established in different cell lineages. Upon tissue differentiation, cellular chromatin from distinct lineages converges according to tissue types but retains stable memories of lineage history, contributing to intra-tissue cell heterogeneity. However, the chromatin landscapes of cells organized in a left-right symmetric pattern are predetermined to be analogous in early progenitors so as to pre-set equivalent states. Finally, genome-wide analysis identifies many regions exhibiting concordant chromatin activity changes that mediate the co-regulation of functionally related genes during differentiation. Collectively, our study reveals the developmental and genomic dynamics of chromatin activity at the single-cell level.
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http://dx.doi.org/10.15252/msb.202010075DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8073016PMC
April 2021

Hepatitis B surface antigen kinetics after discontinuation of and retreatment with oral antivirals in non-cirrhotic HBeAg-positive chronic hepatitis B.

J Viral Hepat 2021 Aug 3;28(8):1121-1129. Epub 2021 May 3.

Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Guangzhou, China.

The outcome of nucleos(t)ide analogues (NAs) discontinuation and retreatment is still uncertain. We evaluated hepatitis B surface antigen (HBsAg) kinetics after NAs discontinuation and during retreatment due to off-treatment clinical relapse among non-cirrhotic HBeAg-positive CHB patients. Four groups were studied: 129 HBeAg-positive patients from a prospective cohort who stopped NAs therapy after achieving sustained response (Group A), 39 patients who received retreatment after off-treatment clinical relapse in the discontinuation group (Group B), 214 patients who maintained treatment after achieving sustained response (Group C) and 291 patients who firstly initiated antiviral treatment (Group D). During a 5-year follow-up, the cumulative incidence of HBsAg loss was significantly higher in Group A than Group C (22.3% vs. 1.6%, p < .001). The quantitative HBsAg (qHBsAg) level at enrolment and NAs discontinuation were independently associated with HBsAg loss. Additionally, patients in Group B showed significantly greater HBsAg loss than those in the Groups C and D, with 5-year cumulative incidences of 9.0%, 1.6% (p = .040) and 0.6% (p < .001), respectively. Moreover, patients in the Group B exhibited better virologic response (100% vs. 98.8%, p < .001) and HBeAg seroconversion (92.6% vs. 69.8%, p < .001) than those in Group D at year 5. Propensity score-matched analysis also showed the similar trend of HBsAg decline. NAs discontinuation with or without subsequent retreatment resulted in a more profound reduction of HBsAg in non-cirrhotic HBeAg-positive patients, suggesting that discontinuation may be a potential cure strategy for those with sustained virological suppression.
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http://dx.doi.org/10.1111/jvh.13526DOI Listing
August 2021

Genetic Causes of Non-pathogenic pv. Isolates in Kiwifruit Orchards.

Front Microbiol 2021 25;12:650099. Epub 2021 Mar 25.

Department of Plant Pathology, College of Agriculture, Guizhou University, Guiyang, China.

Bacterial canker disease has become the largest threat to kiwifruit cultivation and production. A monomorphic subpopulation of pv. biovar 3 (Psa3) is responsible for the pandemic worldwide. Diversity in pathogenicity has been found in the pandemic subpopulation and in other Psa3 subpopulations causing epidemics in China. However, the genetic bases have not yet been elucidated. In this study, 117 Psa3 isolates were identified by Psa- and Psa3-specific primers, and evaluated for pathogenicity. Three isolates G4, G40, and S2 are not pathogenic to kiwifruit and do not elicit hypersensitivity responses (HRs) in non-host leaves. Two isolates, G25 and G35, exhibited attenuated HR-eliciting activity in non-host , but they exhibited greatly and slightly reduced pathogenicity in host plants, respectively. The genomes of the five isolates were sequenced and compared with closely related isolates revealed by MLVA and whole-genome typing methods. The candidate genetic loci responsible for the changes in pathogenicity and HR elicitation, were further evaluated by allele replacement experiments. We found that the three non-pathogenic isolates were formed due to the independent, identical insertion events of ISPsy36 transposon in the gene, encoding a key regulator of type III secretion system (T3SS) and type III effectors (T3Es). In the symptomatic sample from which G4 was isolated, 27% HR negative isolates were detected. In isolate G25, transposon insertion of ISPsy32 at the non-coding sequence upstream of the gene was detected, similar to a previously reported low-virulent Psa3 strain M227. In isolate G35, we detected disruptions of T3Es hopBB1-1 and hopBB1-2, which induce HR in leaves revealed by infiltration. These phenotype-changed isolates were formed at low frequencies during the course of pathogen infection in host plants, supported by the binding assay of ISPsy32 and the non-coding DNA sequences upstream of the gene, the co-isolation of the virulent isolates belonging to the same MLVA clade, and the low levels of transcription of the transposon genes. Taken together, in terms of short-term field evolution, transposon insertions in the T3SS-related genes resulted in the formation of non-pathogenic and low-virulent Psa3 isolates.
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http://dx.doi.org/10.3389/fmicb.2021.650099DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027508PMC
March 2021

Source identification of particulate organic carbon using stable isotopes and n-alkanes: modeling and application.

Water Res 2021 Jun 22;197:117083. Epub 2021 Mar 22.

School of Geography, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, PR China; State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province), Nanjing 210023, PR China. Electronic address:

Particulate organic carbon (POC) sources, which regulate dissolved organic carbon, sediment organic carbon, and inorganic carbon via deposition, degradation, and mineralization, play an important role in lake ecosystems. Linear or Bayesian algorithms on isotope and n-alkanes have been widely used to identify the source proportion of organic carbon. However, the applicability of these methods is ambiguous because of the unilateral advantages of each model and trace factors. To test the applicability of the various methods for identifying POC sources, we analyzed dual isotopes and n-alkanes in surface water samples of Lake Taihu, and Multi-source mixing model and Bayesian mixing model were used to distinguish between endogenous and exogenous contributions. Carbon isotope presented a clear advantage in West Taihu (-21.85 ± 0.78‰) and Southwest Taih (-22.61 ± 1.35‰); nitrogen isotope also showed high values in Meiliang Bay (9.76 ± 0.92‰). The majority of the lake was dominated by short-chain n-alkanes, except for East Taihu Lake (dominated by medium-chain n-alkanes) and areas with riverine input (dominated by long-chain n-alkanes). Different principles between the Bayesian mixing model (based on the Markov Chain Monte Carlo algorithm) and the Multi-source mixing model (based on linear estimation) caused discrepancies in the estimations of source contributions. But the fraction of chemical compounds during the migration process, and the overlap of potential sources play important role in the inconsistency of results. The estimations from the different models were consistent in indicating the dominance of endogenous organic carbon in Lake Taihu (mean of 60.18 ± 20.26%), particularly in the north and western regions (West Taihu, Meiliang Bay, and Southwest Taihu). This was likely due to algal aggregation influenced by human activities and climatic factors.
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http://dx.doi.org/10.1016/j.watres.2021.117083DOI Listing
June 2021

The effects of flux on the clearance of minute virus of mice during constant flux virus filtration.

Biotechnol Bioeng 2021 Apr 3. Epub 2021 Apr 3.

Department of Biomedical Engineering, University of Arkansas, Fayetteville, Arkansas, USA.

Constant flux virus filtration experiments were conducted to evaluate minute virus of mice retention behavior of four commercial virus filters for continuous bioprocessing applications. Fluxes chosen were guided by the Peclet number and the processing logistics as well as based on the filter characteristics. At the low flux condition of 5 (LMH) when diffusive force dominates, a significant breakthrough was observed for all the filtrate fractions for the filtration of a low fouling monoclonal antibody for three of the four filters. When both diffusive and convective forces are equally important at 40 LMH, virus breakthrough in buffer chase was observed only in one of the four filters investigated. When convective force dominates at 60 LMH or above, a high degree of virus clearance was observed for all three parvovirus filters investigated. Our work shed light on virus clearance during constant flux virus filtration for future continuous biomanufacturing.
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http://dx.doi.org/10.1002/bit.27778DOI Listing
April 2021

Methodology-dependent performance of serum HBV RNA in predicting treatment outcomes in chronic hepatitis B patients.

Antiviral Res 2021 05 10;189:105037. Epub 2021 Mar 10.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China. Electronic address:

Background: Whether different serum HBV RNA detection assays can consistently predict treatment outcomes in patients with chronic hepatitis B remains controversial.

Methods: We enrolled 188 patients who had stopped nucleos(t)ide analogues (NAs) (STOP cohort-1, -2) and 78 receiving entecavir (ETV) therapy (ETV cohort) and used double-target (targeting both 5' and 3' ends of the HBV pregenome RNA [DT-RNA]) and three single-target (targeting the S-region [S-RNA], X-region [X-RNA], and poly-A tail of HBV RNA [PolyA-RNA]) assays to predict treatment outcomes.

Results: In STOP cohorts, DT-RNA, S-RNA and X-RNA at NAs cessation showed higher predictive powers for clinical relapse (time-dependent areas under the curve [AUCs] for years 1, 2, 3, and 4 ranged between 0.724 and 0.772 in cohort-1, and between 0.741 and 0.824 in cohort-2) than the PolyA-RNA (AUCs between 0.604 and 0.611 in cohort-1; and between 0.530 and 0.584 in cohort-2). The predictive power for 2-year HBeAg loss of the four targeted RNAs in the ETV cohort at 6 months were similar (AUCs, 0.848, 0.838, 0.825, and 0.801), and superior to that of the HBV DNA level at 6 months (AUC, 0.721).

Conclusion: The outcome prediction performance of serum HBV RNAs is methodology-dependent. PolyA-RNA detection was not recommended to predict off-treatment relapses.
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http://dx.doi.org/10.1016/j.antiviral.2021.105037DOI Listing
May 2021

and to Gene Distribution Characteristics in Gut Specimens from Different Regions of China.

Antibiotics (Basel) 2021 Feb 25;10(3). Epub 2021 Feb 25.

State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.

Antibiotic resistance has become a global public health concern. To determine the distribution characteristics of and in China, gene screening was conducted directly from gut specimens sourced from livestock and poultry, poultry environments, human diarrhea patients, and wild animals from 10 regions, between 2010-2020. The positive rate was 5.09% (356/6991) for and 0.41% (29/6991) for , as detected in gut specimens from seven regions, throughout 2010 to 2019, but not detected in 2020. The detection rate of showed significant differences among various sources: livestock and poultry (14.81%) > diarrhea patients (1.43%) > wild animals (0.36%). The detection rate of was also higher in livestock and poultry (0.88%) than in diarrhea patients (0.17%), and this was undetected in wildlife. This is consistent with the relatively high detection rate of multiple genotypes in livestock and poultry. All instances of coexistence of the and genes, as well as coexistence of genotypes within single specimens, and most new subtypes came from livestock, and poultry environments. Our study indicates that the emergence of and genes in China is closely related to the selective pressure of carbapenem and polymyxin. The gene-based strategy is proposed to identify more resistance genes of concern, possibly providing guidance for the prevention and control of antimicrobial resistance dissemination.
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http://dx.doi.org/10.3390/antibiotics10030233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996585PMC
February 2021

Infestation and seasonal fluctuation of chigger mites on the Southeast Asian house rat () in southern Yunnan Province, China.

Int J Parasitol Parasites Wildl 2021 Apr 11;14:141-149. Epub 2021 Feb 11.

Vector Laboratory, Institute of Pathogens and Vectors, Yunnan Provincial Key Laboratory for Zoonosis Control and Prevention, Dali University, Dali, Yunnan Province, 671000, China.

Chigger mites are the common ectoparasites of rodents and the exclusive vector of scrub typhus. The Southeast Asian house rat () is an important reservoir host and infectious source of some zoonoses including scrub typhus. From April 2016 to March 2017, a 12-month consecutive investigation was made at Jingha village in southern Yunnan of China, which is an important focus of scrub typhus. The infestation and seasonal fluctuation of chigger mites on were studied based on the investigation. From 2,053 captured , a total of 99,221 chiggers were collected and identified as comprising 102 species with very high species diversity. The richness (), diversity index (), evenness () and dominance index () of the chigger community on the rat varied in different months. Of the 102 chigger species, five main species accounted for 84.81% of the total chiggers (84,147/99,221). The five main chiggers were (.) (32.65%), (24.68%), (.) (19.02%), (.) (4.63%) and (.) (3.83%). Of the five chigger species, (.) and (.) are the most important vectors of scrub typhus in China. The five chigger species showed different patterns of seasonal fluctuation. The seasonal fluctuation of (.) belonged to summer-autumn type with the highest peak in July, but (.) mainly appeared in winter and spring with the peak from January to February. The temperature and rainfall were two key factors which influenced the seasonal fluctuation of chigger mites.
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http://dx.doi.org/10.1016/j.ijppaw.2021.02.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7898075PMC
April 2021

Risk and Protective Factors of Generalized Anxiety Disorder of Elite Collegiate Athletes: A Cross-Sectional Study.

Front Public Health 2021 10;9:607800. Epub 2021 Feb 10.

Faculty of Athletic Training, Guangzhou Sport University, Guangzhou, China.

The aim of this study was to examine the prevalence of Generalized Anxiety Disorder (GAD) and its risk and protective factors in elite collegiate athletes. A cross-sectional survey was conducted during the 2019 in-season. A sample of elite collegiate athletes ( = 285) from China completed a self-report form assessing GAD and potential predictors including age, gender, sport type, sport achievement, sport injury, attention deficit hyperactivity disorder (ADHD), fear of failure, mental toughness, and satisfaction in sport. The overall prevalence of GAD symptoms was 22%. The results of zero-order correlation showed that age, gender, sport type, and sport achievement were not significantly related to GAD. However, athletes with a history of sport injury, a high risk of ADHD, and a high level of fear of failure had a significant and positive association with GAD ( = 0.14-0.54). Meanwhile, high levels of mental toughness and satisfaction in sport were significantly and negatively related to GAD ( = -0.22 to -0.24). The results of multiple regression analysis indicated that sport injury, ADHD, and fear of failure were significant risk factors of GAD (β = 0.10-0.40). These findings suggest the necessity to understand the GAD symptoms in elite collegiate athletes. Further research is needed to better understand and support the mental health of this target group.
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http://dx.doi.org/10.3389/fpubh.2021.607800DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7902705PMC
May 2021

The Effect on the Kidney in Patients With Anti-N-methyl D-aspartate Receptor Antibody Encephalitis.

Front Neurol 2021 12;12:601495. Epub 2021 Feb 12.

Department of Neurology, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

The function of the N-methyl-D-aspartate receptor (NMDAR) in the kidney has been studied. However, the effect on the kidney from anti-NAMDAR antibody encephalitis has not been investigated thus far. Case data were collected from 82 patients with anti-NMDAR antibody encephalitis and 166 age- and sex-matched healthy controls (HCs). Clinical characteristics, urinalysis [including urine pH and urine specific gravity (SG)], serum creatinine (Scr), and estimated glomerular filtration rate (eGFR) based on Cr levels were evaluated. At initial admission, urine pH levels and urine SG levels in anti-NMDAR antibody encephalitis patients were significantly higher and lower, respectively, than HCs (both < 0.001). There were no significant differences in Scr and eGFR between anti-NMDAR antibody encephalitis patients and HCs. Urine pH levels in patients with anti-NMDAR antibody <1:32 were significantly lower than those in patients with anti-NMDAR antibody ≥1:32 ( = 0.029). Urine pH levels were significantly lower ( = 0.004) and urine SG levels were significantly higher ( = 0.027) in a follow-up evaluation 3 months after treatment. The changes in urinalysis occur in patients with anti-NMDAR antibody encephalitis. The pathophysiological changes in anti-NMDAR antibody encephalitis were not limited to the CNS.
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http://dx.doi.org/10.3389/fneur.2021.601495DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7907499PMC
February 2021

Knockdown of the DJ-1 (7) gene sensitizes pancreatic cancer to erlotinib inhibition.

Mol Ther Oncolytics 2021 Mar 26;20:364-372. Epub 2021 Jan 26.

Department of Gastroenterology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.

The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib, in combination with gemcitabine, has been shown to be a promising therapy in the treatment of pancreatic cancer. Our previous study showed that DJ-1 promotes invasion and metastasis of pancreatic cancer cells by activating SRC/extracellular signal-regulated kinase (ERK)/uPA. The aim of this study was to evaluate whether knockdown of DJ-1 expression can sensitize pancreatic cancer cells to erlotinib treatment. Knockdown of DJ-1 expression accelerated erlotinib-induced cell apoptosis and improved the inhibitory effect of erlotinib on pancreatic cancer cell proliferation (for the BxPC-3, PANC-1, and MiaPACa-2 cell lines, regardless of KRAS mutation status) and in xenograft tumor growth . Knockdown of DJ-1 decreased K-RAS expression, membrane translocation, and activity in BxPC-3 cells. Knockdown of DJ-1 also decreased K-RAS, H-RAS, and N-RAS expression in PANC-1 and MiaPACa-2 cells. Knockdown of DJ-1 synergistically inhibited AKT and ERK1/2 phosphorylation with erlotinib in pancreatic cancer cells. These findings indicate that DJ-1 may activate the RAS pathway, reinforcing erlotinib drug resistance. Therefore, blocking DJ-1 in combination with the EGFR tyrosine kinase inhibitor erlotinib may be an attractive therapeutic target in pancreatic cancer.
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http://dx.doi.org/10.1016/j.omto.2021.01.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7878983PMC
March 2021

Genetic ablation of fas-activated serine/threonine kinase ameliorates alcoholic liver disease through modulating HuR-SIRT1 mRNA complex stability.

Free Radic Biol Med 2021 04 18;166:201-211. Epub 2021 Feb 18.

Department of Physiology and Pathophysiology, National Key Discipline of Cell Biology, Basic Medicine School, China. Electronic address:

Chronic alcoholism often causes liver injuries characterized by hepatic steatosis, inflammation as well as oxidative stress and finally leads to advanced cirrhosis and liver cancer. Fas-activated serine/threonine kinase (FASTK) and its homologs are gradually known as multifunctional proteins involved in various biological processes; however, the role of FASTK and its family members in alcoholic liver disease (ALD) is still unexplored. Here we found that, among FASTK family members, the expression of FASTK was specifically induced both in livers of mice received chronic ethanol ingestion and in ethanol-stimulated hepatocytes. Animal studies showed that genetic deletion of FASTK attenuated chronic ethanol ingestion-induced liver damage, steatosis, and inflammation. Moreover, FASTK deficiency was associated with improved oxidative/anti-oxidative system homeostasis and reduced reactive oxygen species (ROS) generation in livers upon chronic ethanol stimulation. Importantly, FASTK ablation preserved hepatic sirtuin-1 (SIRT1) expression/activity upon chronic ethanol ingestion and SIRT1 silencing via adenovirus-mediated small interfering RNA transfer diminished FASTK deletion-elicited beneficial effects on alcohol-associated hepatic steatosis, inflammation, and oxidative stress. Mechanistically, ethanol increased the phosphorylation of human antigen R (HuR, a RNA binding protein that stabilizes SIRT1 mRNA) and triggered the dissociation of HuR-SIRT1 mRNA complex, in turn promoting SIRT1 mRNA decay. Genetic deletion of FASTK diminished ethanol-induced HuR phosphorylation and HuR-SIRT1 mRNA complex dissociation, thereby enhancing SIRT1 mRNA stability. Collectively, these findings for the first time highlight a critical role of FASTK in the pathogenesis of ALD and implicate HuR-SIRT1 mRNA complex involves in this process.
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http://dx.doi.org/10.1016/j.freeradbiomed.2021.02.002DOI Listing
April 2021

Stereolithography (SLA) 3D printing of carbon fiber-graphene oxide (CF-GO) reinforced polymer lattices.

Nanotechnology 2021 Mar 16;32(23). Epub 2021 Mar 16.

Department of Mechanical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, People's Republic of China.

Insufficient mechanical properties of stereolithography (SLA)-printed architected polymer metamaterial limits its wide applications such as in the areas of biomedicine and aerospace. One effective solution is to reinforce the structures with micro- or nano- fibers/particles, but their interfaces are critical for the reinforcement. In this work, a carbon fiber-graphene oxide (CF-GO) polymer composite resin and a mild annealing postprocess have been rationally designed and applied into the manufacturing of oct-truss (OCT) lattices.carbon fiber pulling-out experiment was conducted to exhibit the improve effect of GO on the crosslink of the CF and the polymer matrix interface. We found that the maximum reinforcement was realized when the CF-GO (CF: GO is about 3: 1) content is about 0.8 wt%, followed with annealing. Compared with pure polymer lattices, the compression strength of the CF-GO polymer OCT lattices has been significantly increased from ∼0.22 to ∼2.4 MPa, almost 10 times enhancement. Importantly, the compression strength of the CF-GO polymer OCT lattice (3.08 MPa) further increased by ∼30% after optimized annealing. This work suggests an efficient reinforce strategy for SLA-printed metamaterials, and thus can be valuable for advancing various practical applications of mechanical metamaterials.
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http://dx.doi.org/10.1088/1361-6528/abe825DOI Listing
March 2021

Purification of Crude Fructo-Oligosaccharide Preparations Using Probiotic Bacteria for the Selective Fermentation of Monosaccharide Byproducts.

Front Microbiol 2020 26;11:620626. Epub 2021 Jan 26.

Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Giessen, Germany.

Probiotics are microbes that promote health when consumed in sufficient amounts. They are present in many fermented foods or can be provided directly as supplements. Probiotics utilize non-digestible prebiotic oligosaccharides for growth in the intestinal tract, contributing to a healthy microbiome. The oligosaccharides favored by probiotics are species-dependent, as shown by the selective utilization of substrates in mixed sugar solutions such as crude fructo-oligosaccharides (FOS). Enzymatically produced crude FOS preparations contain abundant monosaccharide byproducts, residual sucrose, and FOS varying in chain length. Here we investigated the metabolic profiles of four probiotic bacteria during the batch fermentation of crude FOS under controlled conditions. We found that rapidly utilized most of the monosaccharides but little sucrose or FOS. We therefore tested the feasibility of a microbial fed-batch fermentation process for the purification of FOS from crude preparations, which increased the purity of FOS from 59.2 to 82.5% with a final concentration of 140 g·l. We also tested cell immobilization in alginate beads as a means to remove monosaccharides from crude FOS. This encapsulation concept establishes the basis for new synbiotic formulations that combine probiotic microbes and prebiotic oligosaccharides.
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http://dx.doi.org/10.3389/fmicb.2020.620626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7874009PMC
January 2021

Hf(OTf)-Catalyzed 1,6-Conjugate Addition of 2-Alkyl-azaarenes to -Quinone Methides.

J Org Chem 2021 Feb 1;86(4):3615-3624. Epub 2021 Feb 1.

Department of Organic Chemistry, College of Chemistry, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.

Herein we reported a Hf(OTf)-catalyzed carbon-carbon bond formation reaction between 2-alkyl-azaarenes and -quinone methides (-QMs). This 1,6-conjugate addition protocol offered rapid access to a large array of triarylethane products in good yields. The catalyst loading could be reduced to 1 mol %. Studies pertinent to scale-up reaction and product derivatization were also presented.
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http://dx.doi.org/10.1021/acs.joc.0c02982DOI Listing
February 2021
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