Publications by authors named "Chen Xing"

1,134 Publications

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Visual percepts evoked with an Intracortical 96-channel microelectrode array inserted in human occipital cortex.

J Clin Invest 2021 Oct 19. Epub 2021 Oct 19.

John Moran Eye Center and Biomedical Engineering, University of Utah, Salt Lake City, United States of America.

Background: A long-held dream of scientists is to transfer information directly to the visual cortex of blind individuals, thereby restoring a rudimentary form of sight. However, no clinically available cortical visual prosthesis yet exists.

Methods: We implanted an intracortical microelectrode array consisting of 96 electrodes in the visual cortex of a 57-year-old person with complete blindness for a six- month period. We measured thresholds and the characteristics of the visual percepts elicited by intracortical microstimulation.

Results: Implantation and subsequent explantation of intracortical microelectrodes were carried out without complications. The mean stimulation threshold for single electrodes was 66.8 ± 36.5 μA. We consistently obtained high-quality recordings from visually deprived neurons and the stimulation parameters remained stable over time. Simultaneous stimulation via multiple electrodes were associated with a significant reduction in thresholds (p<0.001, ANOVA test) and evoked discriminable phosphene percepts, allowing the blind participant to identify some letters and recognize object boundaries. Furthermore, we observed a learning process that helped the subject to recognize complex patterns over time.

Conclusions: Our results demonstrate the safety and efficacy of chronic intracortical microstimulation via a large number of electrodes in human visual cortex, showing its high potential for restoring functional vision in the blind.

Trial Registration: ClinicalTrials.gov identifier NCT02983370.

Funding: Funding was provided by grant RTI2018-098969-B-100 from the Spanish Ministerio de Ciencia Innovación y Universidades, by grant PROMETEO/2019/119 from the Generalitat Valenciana (Spain), by the Bidons Egara Research Chair of the University Miguel Hernández (Spain) and by the John Moran Eye Center of the University of Utah (US).
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http://dx.doi.org/10.1172/JCI151331DOI Listing
October 2021

Mitogenome and phylogenetic analyses support rapid diversification among species groups of small-eared shrews genus (Mammalia: Eulipotyphla: Soricidae).

Zool Res 2021 Nov;42(6):739-745

Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, and Guangdong Provincial Key Laboratory of Single Cell Technology and Application, Southern Medical University, Guangzhou, Guangdong 510515, China.

The small-eared shrew genus is the third largest in the family Soricidae and occurs in North, Central, and northern South America. In Mexico and Central and South America, most species inhabit geographically isolated moist, montane habitats at middle and high elevations in a typical sky-island pattern. The 49 recognized species have been partitioned into as many as six species groups based on morphological and molecular phylogenetic studies. The relationships among these species groups are poorly resolved, and their evolutionary histories, including migration patterns and locomotor adaptations, remain unclear. Herein, we provide a new phylogeny incorporating complete mitochondrial genomes (mitogenomes) and supermatrix approach. We compared different evolutionary scenarios using approximately unbiased (AU), Kishino-Hasegawa (KH), and Shimodaira-Hasegawa (SH) statistical tests. The phylogenetic hypothesis based on mitogenomes revealed novel relationships supporting a basal position for the -group in the genus, and a close relationship between and one clade of the -group. The former relationship is consistent with the least derived humerus morphology and northern distribution of the species. The latter relationship implies multiple migrations between Central and South America. The lack of fine resolution for the species group relationships may be due partly to the lack of taxon sampling. In contrast, multi-approach analyses suggest that the unresolved relationships may be a result of rapid diversification during the early stages of evolution.
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http://dx.doi.org/10.24272/j.issn.2095-8137.2021.199DOI Listing
November 2021

Polymorphonuclear neutrophils promote endothelial apoptosis by enhancing adhesion upon stimulation by intermittent hypoxia.

Sleep Breath 2021 Oct 11. Epub 2021 Oct 11.

Department of Respiratory and Critical Care Medicine, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China.

Purpose: This study explored the interactive effects between polymorphonuclear neutrophils (PMNs) and vascular endothelial cells under intermittent hypoxia (IH) and investigated the mechanisms underlying these effects.

Methods: Endothelial cells were co-cultured with PMNs isolated from rats exposed to normoxia or IH. The PMN apoptotic rate was determined using flow cytometry. Expression of apoptosis-related proteins in the endothelial cells were evaluated using Western blotting, and the levels of intercellular adhesion molecules in the co-culture supernatants were measured using enzyme-linked immunosorbent assay.

Results: The PMN apoptotic rate in the IH-exposed rat group was significantly lower than that of the normoxia control group. There was a positive relationship between the PMN apoptotic rate and IH exposure time. In endothelial cells co-cultured with PMNs isolated from IH-exposed rats, a significant increase in the protein expression levels of Bax, Bcl-2, and caspase-3 and a significant decrease in the Bcl-2/Bax ratio were observed. Furthermore, the intercellular cell adhesion molecule-1(ICAM-1) and E-select element (E-S) levels were elevated significantly in the co-cultured supernatants of endothelial cells and PMNs from IH-exposed rats compared to that from controls. The above IH-induced alterations were partially restored by tempol pretreatment.

Conclusions: The apoptotic rate was low in PMNs from IH-exposed rats, which consequently increased the apoptotic signals in endothelial cells in vitro. This may be associated with the increased levels of intercellular adhesion molecules. Further, tempol partially attenuates the PMN-mediated pro-apoptotic effects on endothelial cells under IH.
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http://dx.doi.org/10.1007/s11325-021-02503-zDOI Listing
October 2021

Hsp90-associated DNA replication checkpoint protein and proteasome-subunit components are involved in the age-related macular degeneration.

Chin Med J (Engl) 2021 Sep 20;134(19):2322-2332. Epub 2021 Sep 20.

Department of Ophthalmology, Peking University First Hospital, Beijing 100034, China.

Background: Age-related macular degeneration (AMD) is the leading cause of vision loss worldwide. However, the mechanisms involved in the development and progression of AMD are poorly delineated. We aimed to explore the critical genes involved in the progression of AMD.

Methods: The differentially expressed genes (DEGs) in AMD retinal pigment epithelial (RPE)/choroid tissues were identified using the microarray datasets GSE99248 and GSE125564, which were downloaded from the gene expression omnibus database. The overlapping DEGs from the two datasets were screened to identify DEG-related biological pathways using gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses. The hub genes were identified from these DEGs through protein-protein interaction network analyses. The expression levels of hub genes were evaluated by quantitative real-time polymerase chain reaction following the induction of senescence in ARPE-19 with FK866. Following the identification of AMD-related key genes, the potential small molecule compounds targeting the key genes were predicted by PharmacoDB. Finally, a microRNA-gene interaction network was constructed.

Results: Microarray analyses identified 174 DEGs in the AMD RPE compared to the healthy RPE samples. These DEGs were primarily enriched in the pathways involved in the regulation of DNA replication, cell cycle, and proteasome-mediated protein polyubiquitination. Among the top ten hub genes, HSP90AA1, CHEK1, PSMA4, PSMD4, and PSMD8 were upregulated in the senescent ARPE-19 cells. Additionally, the drugs targeting HSP90AA1, CHEK1, and PSMA4 were identified. We hypothesize that Hsa-miR-16-5p might target four out of the five key DEGs in the AMD RPE.

Conclusions: Based on our findings, HSP90AA1 is likely to be a central gene controlling the DNA replication and proteasome-mediated polyubiquitination during the RPE senescence observed in the progression of AMD. Targeting HSP90AA1, CHEK1, PSMA4, PSMD4, and/or PSMD8 genes through specific miRNAs or small molecules might potentially alleviate the progression of AMD through attenuating RPE senescence.
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http://dx.doi.org/10.1097/CM9.0000000000001773DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8510006PMC
September 2021

Environmental geochemical characteristics of rare-earth elements in surface waters in the Huainan coal mining area, Anhui Province, China.

Environ Geochem Health 2021 Oct 8. Epub 2021 Oct 8.

Anhui Province Engineering Laboratory for Mine Ecological Remediation, Hefei, 230601, Anhui, China.

This study investigated the environmental geochemical characteristics of rare-earth elements (REEs) in surface waters in the Huainan mining area, Anhui Province, China. The REEs concentrations were determined by ICP-MS, and the inorganic species of dissolved REEs in the river and coal mining subsidence area water samples were calculated by using the Visual MINTEQ (version 3.1) code. On this basis, the distribution and geochemical characteristics of REEs in the surface waters were systematically analyzed, and the main inorganic species of REEs were investigated. The results showed the following: (1) The REEs concentrations in the surface waters were relatively low, ranging from 0.1361 to 0.3536 μg/L, and the average ∑REEs concentration was 0.2062 μg/L. Compared with light rare-earth elements (LREEs), heavy rare-earth elements (HREEs) were significantly enriched, with an average enrichment factor of 1.4642. Due to the interaction of high pH values and high cation concentrations, the ∑REEs content in the subsidence area water was significantly lower than that in the river water. (2) The distribution pattern of REEs in the surface waters normalized against the North American Shale Composite (NASC) showed that the REEs in the study area had different degrees of cerium (Ce) and europium (Eu) anomalies. The negative Ce anomalies were probably closely related to the pH conditions, whereas the positive Eu anomalies were mainly attributed to preferential chemical weathering and the dissolution of feldspar minerals. (3) The simulation results obtained by using Visual MINTEQ code showed that the dominant and typically inorganic complex form of REEs in the surface waters was carbonate complexes, and this form was one of the reasons for the enrichment of HREEs in the surface water.
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http://dx.doi.org/10.1007/s10653-021-01121-8DOI Listing
October 2021

TpIRT1 from Polish wheat (Triticum polonicum L.) enhances the accumulation of Fe, Mn, Co, and Cd in Arabidopsis.

Plant Sci 2021 Nov 16;312:111058. Epub 2021 Sep 16.

Triticeae Research Institute, Sichuan Agricultural University, Wenjiang, 611130, Sichuan, China. Electronic address:

Uptake and internal transport of micronutrients are essential for plant growth, development, and yield. In this regard, Iron Regulated Transporters (IRTs) from the Zinc Regulated Transporter (ZRT)/IRT-related protein (ZIP) family play an important role in transition metal uptake. Most studies have been focused on IRT1-like proteins in diploid species. Information on IRT1-like proteins in polyploids is limited. Here, we studied the function of TpIRT1A and TpIRT1B homoeologs in a tetraploid crop, Polish wheat (Triticum polonicum L.). Our results highlighted the importance of TpIRT1 in mediating the uptake and translocation of Fe, Mn, Co, and Cd with direct implications for wheat yield potential. Both TpIRT1A and TpIRT1B were located at the plasma membrane and internal vesicle-like organelle in protoplasts of Arabidopsis thaliana L. and increased Cd and Co sensitivity in yeast. The over-expression of TpIRT1B in A. thaliana increased Fe, Mn, Co, and Cd concentration in its tissues and improved plant growth under Fe, Mn, and Co deficiencies, while increased the sensitivity to Cd compared to wild type. Functional analysis of IRT1 homoeologs from tetraploid and diploid ancestral wheat species in yeast disclosed four distinct amino acid residues in TdiIRT1B (T. dicoccum L. (Schrank)) and TtuIRT1B (T. turgidum L.). Together, our results increase the knowledge of IRT1 function in a globally important crop, wheat.
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http://dx.doi.org/10.1016/j.plantsci.2021.111058DOI Listing
November 2021

Emerging Role of Mitophagy in the Heart: Therapeutic Potentials to Modulate Mitophagy in Cardiac Diseases.

Oxid Med Cell Longev 2021 23;2021:3259963. Epub 2021 Sep 23.

Department of Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.

The normal function of the mitochondria is crucial for most tissues especially for those that demand a high energy supply. Emerging evidence has pointed out that healthy mitochondrial function is closely associated with normal heart function. When these processes fail to repair the damaged mitochondria, cells initiate a removal process referred to as mitophagy to clear away defective mitochondria. In cardiomyocytes, mitophagy is closely associated with metabolic activity, cell differentiation, apoptosis, and other physiological processes involved in major phenotypic alterations. Mitophagy alterations may contribute to detrimental or beneficial effects in a multitude of cardiac diseases, indicating potential clinical insights after a close understanding of the mechanisms. Here, we discuss the current opinions of mitophagy in the progression of cardiac diseases, such as ischemic heart disease, diabetic cardiomyopathy, cardiac hypertrophy, heart failure, and arrhythmia, and focus on the key molecules and related pathways involved in the regulation of mitophagy. We also discuss recently reported approaches targeting mitophagy in the therapy of cardiac diseases.
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http://dx.doi.org/10.1155/2021/3259963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8483925PMC
September 2021

Redox-responsive glycosylated combretastatin A-4 derivative as novel tubulin polymerization inhibitor for glioma and drug delivery.

Drug Dev Res 2021 Sep 29. Epub 2021 Sep 29.

Department of Translational Medicine Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.

Combretastatin A-4 (CA4), a tubulin inhibitor, binds to the colchicine site of tubulin, inhibits tubulin polymerization, and leads to the apoptosis of tumor cells. However, the poor hydrophilicity and blood-brain barrier (BBB) penetration ability of CA4 hampers its application in the treatment of glioma. In this study, a novel combretastatin A-4 derivative (CA4D) was designed and developed, which was further conjugated with glucose via disulfide-bond-bridged (CA4D-SS-Glu) to enhance the BBB penetration capacity. The obtained CA4D-SS-Glu conjugate displayed a suitable water partition coefficient and the superior ability across BBB in vitro and in vivo. In addition, the CA4D-SS-Glu exhibited rapid redox-responsive drug release in the presence of glutathione, enhanced in vitro cytotoxicity, and cell apoptosis. Our data further confirmed that CA4D-SS-Glu inhibited proliferation, and restrained migration via affecting microtubule stabilization. Additionally, the conjugate also showed the highest antiproliferative and antitumor action on glioma in vivo as compared to CA4D and CA4. Taken together, the novel CA4D-SS-Glu conjugate possess improved physicochemical property and BBB penetration ability, reduction triggered release of CA4D, and efficient antiproliferative activity. These results provided a novel and effective entry to the treatment of glioma.
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http://dx.doi.org/10.1002/ddr.21889DOI Listing
September 2021

Roles of alkali metal dopants and surface defects on polymeric carbon nitride in photocatalytic peroxymonosulfate activation towards water decontamination.

J Hazard Mater 2021 Sep 25;424(Pt A):127292. Epub 2021 Sep 25.

School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, China; Key Laboratory of Nanominerals and Pollution Control of Higher Education Institutes, Hefei University of Technology, Hefei 230009, China.

Polymeric carbon nitride (PCN) has been extensively employed in peroxymonosulfate (PMS) activation for water decontamination. However, limited photocatalytic efficiency can be achieved by pristine PCN due to its intrinsic deficiencies like high electron-hole recombination rate and resistance to charge transfer. Herein, in a two-stage thermal treatment process, the nontoxic and stable Na and K were successfully anchored among the PCN skeleton with surface defects created, leading to an elevated photocatalytic activity for PMS activation. The SO· and O were identified as the dominant reactive oxygen species, which were generated from electron transfer processes between PMS and catalyst. Experimental and theoretical analyses suggested that the defective structures and metal dopants improved the optical properties of catalyst, endowing it a wider light absorption range and a lower energy barrier for electron transitions. The modified structures were also beneficial to electron transfer processes due to the weaker electron confinement effect, accelerating the production of SO· on the defective sites and O on the metal sites. The synergy of radical and non-radical species weakened the influence of side reactions between radicals from PMS and coexisting inorganic anions in practical water, hence to promote the resistance of modified catalysts in complex water matrices.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127292DOI Listing
September 2021

Ferromagnetic resonance modes of a synthetic antiferromagnet at low magnetic fields.

J Phys Condens Matter 2021 Sep 27. Epub 2021 Sep 27.

Department of Optical Science and Engineering, Fudan University, 220 Handan Rd, Wu Jiao Chang, Yangpu District, Shanghai, Shanghai, 200433, CHINA.

One key advantage of antiferromagnets over ferromagnets is the high magnetic resonance frequencies that enable ultrafast magnetization switching and oscillations. Among a variety of antiferromagnets, the synthetic antiferromagnet (SAF) is a promising candidate for high-speed spintronic devices design. In this paper, micromagnetic simulations are employed to study the resonance modes in a SAF structure consisting of two identical CoFeB ferromagnetic (FM) layers that are antiferromagnetically coupled via interlayer exchange coupling. When the external bias magnetic field is small enough to ensure the magnetizations of two ferromagnetic sublayers remain antiparallel alignments, we find that there exist two resonance modes with different precession chirality, namely y-component synchronized mode and z-component synchronized mode, respectively. These two resonance modes show different features from the conventional in-phase acoustic mode and out-of-phase optic mode. The simulation results are in good agreement with our theoretical analyses.
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http://dx.doi.org/10.1088/1361-648X/ac2a79DOI Listing
September 2021

Understanding the experiences of patients with cancers in hospitals during COVID-19 pandemic in China: A qualitative research study.

Nurs Open 2021 Sep 26. Epub 2021 Sep 26.

Department of Gynecology Oncology, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China.

Aim: To explore the experiences of patients with cancers in hospitals during the COVID-19 pandemic.

Design: A qualitative research study.

Methods: Using a phenomenological approach, we enrolled 22 patients with cancers in the Hunan Cancer Hospital from 20 February 2020 to 10 April 2020. The interviews were conducted face-to-face and were analysed by Colaizzi's 7-step method. This study aligns with the COREQ checklist.

Results: The experiences of patients with cancers in hospitals during the COVID-19 pandemic can be categorized into four major themes: (1) emotional changes; (2) delays in visiting hospital; (3) barriers to accessing medical care services, and (4) inconvenience related to logistics services.
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http://dx.doi.org/10.1002/nop2.1073DOI Listing
September 2021

Effect of ultrasound on the properties of rice bran protein and its chlorogenic acid complex.

Ultrason Sonochem 2021 Sep 17;79:105758. Epub 2021 Sep 17.

School of Food Science, Northeast Agricultural University, Harbin 150030, China. Electronic address:

Ultrasound technology was used to treat rice bran protein (RBP), and the structural and functional properties of ultrasonically treated RBP (URBP) and its chlorogenic acid (CA) complex were studied. When ultrasonic power of 200 W was applied for 10 min, the maximum emission peak λ of the URBP-CA complex in the fluorescence spectrum was red-shifted by 3.6 nm compared to that of the untreated complex. The atomic force microscope (AFM) analysis indicated that the surface roughness of the complex was minimized (3.89 nm) at the ultrasonic power of 200 W and treatment time of 10 min. Under these conditions, the surface hydrophobicity (H) was 1730, the contents of the α-helix and β-sheet in the complex were 2.97% and 6.17% lower than those in the untreated sample, respectively, the particle size decreased from 106 nm to 18.2 nm, and the absolute value of the zeta-potential increased by 11.0 mV. Therefore, ultrasonic treatment and the addition of CA changed the structural and functional properties of RBP. Moreover, when ultrasonic power of 200 W was applied for 10 min, the solubility, emulsifying activity index (EAI), and emulsion stability index (ESI) were 68%, 126 m/g, and 37 min, respectively.
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http://dx.doi.org/10.1016/j.ultsonch.2021.105758DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8473761PMC
September 2021

Emulsion gels stabilized by soybean protein isolate and pectin: Effects of high intensity ultrasound on the gel properties, stability and β-carotene digestive characteristics.

Ultrason Sonochem 2021 Sep 16;79:105756. Epub 2021 Sep 16.

School of Food Science, Northeast Agricultural University, Harbin, 150030, China. Electronic address:

In this study, soybean protein isolate (SPI) and pectin emulsion gels were prepared by thermal induction, and the effects of high intensity ultrasound (HIU) at various powers (0, 150, 300, 450 and 600 W) on the structure, gel properties and stability of emulsion gels were investigated. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) showed that the interaction between SPI and pectin was enhanced and the crystallinity of the emulsion gels was changed due to the HIU treatment. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) observations revealed that the particle size of the emulsion gels was decreased significantly by HIU treatment. The emulsion gel structure became more uniform and denser, which was conducive to storage stability. In addition, according to the low field nuclear magnetic resonance (LF-NMR) analysis, HIU treatment had no obvious impact on the content of bound water as the power increased to 450 W, while the content of free water decreased gradually and became immobilized water, which indicated that the water holding capacity of the emulsion gels was enhanced. Compared with untreated emulsion gel, differential scanning calorimetry (DSC) analysis showed that the denaturation temperature reached 131.9 ℃ from 128.2 ℃ when treated at 450 W. The chemical stability and bioaccessibility of β-carotene in the emulsion gels were improved significantly after HIU treatment during simulated in vitro digestion.
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http://dx.doi.org/10.1016/j.ultsonch.2021.105756DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8473777PMC
September 2021

Evolution of the Toroidal Flux of CME Flux Ropes during Eruption.

Innovation (N Y) 2020 Nov 5;1(3):100059. Epub 2020 Nov 5.

School of Astronomy and Space Science, Nanjing University, Nanjing 210046, China.

Coronal mass ejections (CMEs) are large-scale explosions of the coronal magnetic field. It is believed that magnetic reconnection significantly builds up the core structure of CMEs, a magnetic flux rope, during the eruption. However, the quantitative evolution of the flux rope, particularly its toroidal flux, is still unclear. In this paper, we study the evolution of the toroidal flux of the CME flux rope for four events. The toroidal flux is estimated as the magnetic flux in the footpoint region of the flux rope, which is identified by a method that simultaneously takes the coronal dimming and the hook of the flare ribbon into account. We find that the toroidal flux of the CME flux rope for all four events shows a two-phase evolution: a rapid increasing phase followed by a decreasing phase. We further compare the evolution of the toroidal flux with that of the Geostationary Operational Environmental Satellites soft X-ray flux and find that they are basically synchronous in time, except that the peak of the former is somewhat delayed. The results suggest that the toroidal flux of the CME flux rope may be first quickly built up by the reconnection mainly taking place in the sheared overlying field and then reduced by the reconnection among the twisted field lines within the flux rope, as enlightened by a recent 3D magnetohydrodynamic simulation of CMEs.
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http://dx.doi.org/10.1016/j.xinn.2020.100059DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8454547PMC
November 2020

Species diversity and community structure of crustacean zooplankton in the highland small waterbodies in Northwest Yunnan, China.

PeerJ 2021 2;9:e12103. Epub 2021 Sep 2.

State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.

Small waterbodies are a unique aquatic ecosystem with an increasing recognition for their important role in maintaining regional biodiversity and delivering ecosystem services. However, small waterbodies in Northwest Yunnan, one of the most concerned global biodiversity hot-spots, remain largely unknown. Here, we investigated the community structure of crustacean zooplankton and their relationships with limnological, morphometric and spatial variables in the highland small waterbodies in Northwest Yunnan in both the dry (October 2015) and rainy (June 2016) seasons. A total of 38 species of crustacean zooplankton were identified in our study, which is significantly higher than many other reported waterbodies in the Yunnan-Guizhou plateau as well as in the Yangtze River basin. This suggests that the highland small waterbodies are critical in maintaining regional zooplankton diversity in Northwest Yunnan. Meanwhile, we found limnological variables could explain most variation of crustacean zooplankton community, comparing to the morphometric and spatial variables in both the rainy and dry seasons. Our study revealed the diversity and community structure of crustacean zooplankton in the highland small waterbodies in Northwest Yunnan and highlighted the importance of small waterbodies in maintaining regional biodiversity.
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http://dx.doi.org/10.7717/peerj.12103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8418800PMC
September 2021

Unmarked gene editing in Clavibacter michiganensis using CRISPR/Cas9 and 5-fluorocytosine counterselection.

Mol Plant Microbe Interact 2021 Sep 20. Epub 2021 Sep 20.

China Agricultural University, 34752, Plant Pathology, Yuanmingyuan West Rd. Haidian District, Beijing, China, 100193;

Plant pathogenic bacteria in the genus Clavibacter are important quarantine species that cause considerable economic loss worldwide. The development of effective gene editing techniques and additional selectable markers is essential to expedite gene functional analysis in this important Gram-positive genus. The current study details a highly efficient unmarked CRISPR/Cas9-mediated gene editing system in Clavibacter michiganensis (Cm), which couples the expression of cas9 and sgRNA with homology-directed repair templates and the negative selectable marker codA::upp within a single plasmid. Initial experiments indicated that CRISPR/Cas9-mediated transformation could be utilized for both site directed mutagenesis, in which an A to G point mutation was introduced at the 128th nucleotide of the Cm rpsL gene to generate a streptomycin resistant mutant, and complete gene knockout, in which the deletion of the Cm celA or katA genes resulted in transformants that lacked cellulase and catalase activity, respectively. In subsequent experiments the introduction of the codA::upp cassette into the transformation vector facilitated the counterselection of unmarked transformants by incubation in the absence of the selective antibiotic, followed by plating on M9 agar containing 100 μg/ml 5-fluorocytosine (5-FC), in which an unmarked katA mutant lacking the transformation vector was recovered. Compared to conventional homologous recombination, the unmarked CRISPR/Cas9-mediated system was more useful and convenient as it allowed the template plasmid to be reused repeatedly to facilitate the editing of multiple genes, which constitutes a major advancement that could revolutionize research into Cm and other Clavibacter species.
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http://dx.doi.org/10.1094/MPMI-07-21-0179-TADOI Listing
September 2021

Epidemiological characteristics and clinical manifestations of pediatric patients with COVID-19 in China: A multicenter retrospective study.

Pediatr Investig 2021 Aug 12:e12282. Epub 2021 Aug 12.

Chinese University of Hong Kong Shatin Hong Kong China.

Importance: The Coronavirus disease 2019 (COVID-19) global pandemic poses a considerable challenge for pediatricians.

Objective: This study aimed to identify the epidemiological characteristics and clinical features of pediatric patients with COVID-19 in China.

Methods: This multicenter retrospective study included pediatric patients from 46 hospitals in China, covering 12 provinces and two municipalities. Epidemiological, demographic, clinical, laboratory, treatment, and outcome data were analyzed.

Results: In total, 211 pediatric patients with COVID-19 were included in this study. The median age was 7.0 years (range: 22 days to 18 years). Approximately 16.3% of the patients exhibited asymptomatic infections, 23.0% had upper respiratory tract infections, and 60.7% had pneumonia, including two with severe pneumonia and one with critical illness. Approximately 78.7% of the pediatric patients occurred in familial clusters. The most three common symptoms or signs at onset in children with COVID-19 were fever (54.5%), cough (49.3%), and pharyngeal congestion (20.8%). Only 17.6% of the patients presented with decreased lymphocyte count, whereas 13.6% had increased lymphocyte count. Among the patients with pneumonia who exhibited abnormal chest computed tomography findings, 18.2% (23/127) of the patients had no other symptoms. Generally, the chest radiographs showed abnormalities that affected both lungs (49.6%); ground-glass opacity (47.2%) was the most common manifestation. The cure and improvement rates were 86.7% (183/211) and 13.3% (28/211), respectively. Only one patient with an underlying condition received invasive mechanical ventilation; none of the patients died.

Interpretation: Similar to adults, children of all age groups are susceptible to COVID-19. Fortunately, most pediatric patients have mild symptoms or remain asymptomatic, despite the high incidence of pneumonia. Decreased proportions of white blood cells and lymphocytes are less frequent in children than in adults.
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http://dx.doi.org/10.1002/ped4.12282DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8441896PMC
August 2021

NLRP3 Inflammasome-Dependent Increases in High Mobility Group Box 1 Involved in the Cognitive Dysfunction Caused by Tau-Overexpression.

Front Aging Neurosci 2021 3;13:721474. Epub 2021 Sep 3.

Department of Army Occupational Disease, State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing, China.

Tau hyperphosphorylation is a characteristic alteration present in a range of neurological conditions, such as traumatic brain injury (TBI) and neurodegenerative diseases. Treatments targeting high-mobility group box protein 1 (HMGB1) induce neuroprotective effects in these neuropathologic conditions. However, little is known about the interactions between hyperphosphorylated tau and HMGB1 in neuroinflammation. We established a model of TBI with controlled cortical impacts (CCIs) and a tau hyperphosphorylation model by injecting the virus encoding human P301S tau in mice, and immunofluorescence, western blotting analysis, and behavioral tests were performed to clarify the interaction between phosphorylated tau (p-tau) and HMGB1 levels. We demonstrated that p-tau and HMGB1 were elevated in the spatial memory-related brain regions in mice with TBI and tau-overexpression. Animals with tau-overexpression also had significantly increased nucleotide-binding oligomerization domain-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome activation, which manifested as increases in apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), activating caspase-1 and interleukin 1 beta (IL-1β) levels. In addition, NLRP3 mice and the HMGB1 inhibitor, glycyrrhizin, were used to explore therapeutic strategies for diseases with p-tau overexpression. Compared with wild-type (WT) mice with tau-overexpression, downregulation of p-tau and HMGB1 was observed in NLRP3 mice, indicating that HMGB1 alterations were NLRP3-dependent. Moreover, treatment with glycyrrhizin at a late stage markedly reduced p-tau levels and improved performance in the Y- and T-mazes and the ability of tau-overexpressing mice to build nests, which revealed improvements in spatial memory and advanced hippocampal function. The findings identified that p-tau has a triggering role in the modulation of neuroinflammation and spatial memory in an NLRP3-dependent manner, and suggest that treatment with HMGB1 inhibitors may be a better therapeutic strategy for tauopathies.
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http://dx.doi.org/10.3389/fnagi.2021.721474DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8446370PMC
September 2021

Co-occurrence of chromophytic phytoplankton and the Vibrio community during Phaeocystis globosa blooms in the Beibu Gulf.

Sci Total Environ 2021 Sep 11;805:150303. Epub 2021 Sep 11.

Key Laboratory of Ministry of Education for Environment Change and Resources Use in Beibu Gulf, Guangxi Key Laboratory of Earth Surface Processes and Intelligent Simulation, Nanning Normal University, 175 East Mingxiu Road, Nanning 530001, Guangxi, People's Republic of China. Electronic address:

Accumulating research evidence has revealed that harmful algal blooms (HABs) can substantially affect the community structures of phytoplankton and heterotrophic bacteria in marine ecosystems. However, little is known about their species-specific interactions between phytoplankton and heterotrophic bacteria during the HABs period and about their interaction shifts in response to blooms. From this perspective, we investigated the co-occurrence of chromophytic phytoplankton and Vibrio during Phaeocystis globosa blooms in the Beibu Gulf. The results showed that Vibrio communities were distinct during the blooms, and P. globosa blooms resulted in a decline in phytoplankton alpha diversity, revealing that the blooms could affect their community compositions. The regression lines between the Shannon indices and Bray-Curtis distances of phytoplankton and Vibrio showed positive correlations with each other (p < 0.001), suggesting that they may have intrageneric symbiotic interactions overall. In addition, network analysis further demonstrated that relationships between phytoplankton and Vibrio were dominated by positive correlations, and more interaction modules were observed during the blooms, revealing that the blooms intensified synergistic association and mutual symbiotic interactions between them. Environmental factors (SiO, NH, NO and TN,) and P. globosa density more deeply affected network interactions between phytoplankton and Vibrio during the periods of P. globosa blooms than those before the blooms and after the blooms. This study provided new insight to elucidate community structure and interaction relationships between phytoplankton and Vibrio in response to P. globosa blooms and their ecological effects in marine ecosystems.
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http://dx.doi.org/10.1016/j.scitotenv.2021.150303DOI Listing
September 2021

In situ remediation of Cr(VI) contaminated groundwater by ZVI-PRB and the corresponding indigenous microbial community responses: a field-scale study.

Sci Total Environ 2021 Sep 11;805:150260. Epub 2021 Sep 11.

Nanjing Kangdi Environmental Protection Technology Co., LTD, Nanjing 21000, China.

The performance of a permeable reactive barrier (PRB) for the in situ remediation of hexavalent chromium [Cr(VI)] contaminated groundwater, and the resulted responses in the indigenous microbial community, were investigated in a field-scale study. The PRB consisted of a mixture of zero-valent iron (ZVI), gravel and sand. The results showed that the PRB segment with 20% active reaction medium (ZVI) was able to successfully reduce Cr(VI) via chemical reduction from 27.29-242.65 mg/L to below the clean-up goal of 0.1 mg/L, and can be scaled-up under field conditions. It was found that the ZVI induced significant changes in the indigenous microbial community structure and compositions in the area of the PRB and those areas downgradient. The competitive growth among Cr(VI)-reducing bacteria (the reduced abundance of Hydrogenophaga, Pseudomonas, Exiguobacterium and Rhodobacter, along with the enrichment of Rivibacter and Candidatus_Desulforudis) were observed in PRB. In addition, Cr(VI)-reducing bacteria (Hydrogenophaga, Pseudomonas, Exiguobacterium and Rhodobacter) were enriched in the downgradient of PRB, indicating that Cr(VI) can be further bio-reduced to Cr(III). The Cr(VI) bio-reduction could serve as a secondary mechanism for further removal of Cr(VI) from contaminated groundwater, suggesting that the actual lifetime of a PRB can be prolonged, which is important for the design and economic assessment of a PRB. Further analysis revealed that pH, dissolved oxygen, Cr(VI) level, the oxidation-reduction potential, and temperature were the main environmental factors influencing the subsurface microbial community compositions.
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http://dx.doi.org/10.1016/j.scitotenv.2021.150260DOI Listing
September 2021

Efficacy of Huaiqihuang granules as adjuvant therapy for bronchial asthma in children: a real-world study.

Zhongguo Dang Dai Er Ke Za Zhi 2021 Sept 15;23(9):877-881

Children's Hospital of Capital Institute of Pediatrics, Beijing 100020, China(LiuC-H, Email:

Objectives: To study the efficacy of Huaiqihuang granules as adjuvant therapy for bronchial asthma in children.

Methods: A multicenter, prospective, and registered real-world study was performed for the children, aged 2-5 years, who had a confirmed diagnosis of bronchial asthma in the outpatient service of 21 hospitals in China. Among these children, the children treated with medications for long-term asthma control (inhaled corticosteroid and/or leukotriene receptor antagonist) without Huaiqihuang granules were enrolled as the control treatment group, and those treated with medications for long-term asthma control combined with Huaiqihuang granules were enrolled as the combined treatment group. The medical data of all children were collected. Outpatient or telephone follow-up was performed at weeks 4, 8, 12, 20, 28, and 36 after treatment, including asthma attacks and rhinitis symptoms. A statistical analysis was performed for the changes in these indices.

Results: There was no significant difference in the frequency of asthma attacks or rhinitis attacks between the two groups before treatment (>0.05). After treatment, the combined treatment group had significantly lower frequencies of asthma attacks, severe asthma attacks, and rhinitis attacks compared with the control treatment group (<0.05). There was no signification difference in the incidence rate of adverse reactions between the two groups (=0.667).

Conclusions: Huaiqihuang granules in addition to medications for long-term asthma control can alleviate the symptoms of bronchial asthma and rhinitis and improve the level of asthma control in children with bronchial asthma, with good safety and little adverse effect. .
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http://dx.doi.org/10.7499/j.issn.1008-8830.2106028DOI Listing
September 2021

An Amorphous-Crystalline Nanosheet Arrays Structure for Ultrahigh Electrochemical Performance Supercapattery.

Small 2021 Oct 12;17(41):e2102565. Epub 2021 Sep 12.

School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 611731, P. R. China.

Hybrid supercapacitors (HSCs), also called supercapattery, which can substitute for low power density batteries have attracted extensive interest. However, when HSCs comes to commercial applications, there is still space for improvement in energy density. It seems that designing of electrode with high capacity is an effective measure. Herein, amorphous-crystalline MoO -Ni S /NF-0.5 nanosheet arrays are developed as battery-type electrodes. Specifically, the sheet-like structure of crystalline Ni S can achieve rich structural nanocrystallization, improving the redox reaction efficiency. Meanwhile, the disordered structure and irregular surface of the amorphous MoO are conducive to maximize the contact between the electrode and electrolyte, slowing down the volume change caused by the continuous charge-discharge process. As a result, it displays an ultrahigh areal specific capacity of 8.52 C cm at 5 mA cm , and superior lifespan up to 7500 cycles with 90.0% retention. Further, when assembled into HSCs, the specific capacity reaches 1.47 C cm , corresponding to an energy density of 4.18 mWh cm at a power density of 0.34 mW cm . Totally, the design of the unique structure displays a valuable measure for rational development of high energy density hybrid energy storage devices that are not limited to supercapacitors.
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http://dx.doi.org/10.1002/smll.202102565DOI Listing
October 2021

Attenuation of cerebral edema facilitates recovery of glymphatic system function after status epilepticus.

JCI Insight 2021 Sep 8;6(17). Epub 2021 Sep 8.

Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China.

Status epilepticus (SE) is a neurological emergency usually accompanied by acute cerebral edema and long-term cognitive impairment, and is characterized by neurodegeneration and aberrant hyperphosphorylated tau protein (p-tau) aggregation. The glia-lymphatic (glymphatic) system plays a central role in facilitating the clearance of metabolic waste from the brain, but its relationship with cerebral edema and cognitive dysfunction after SE is unclear. We hypothesized that cerebral edema after SE might impair glymphatic system function through compression, thus leading to impaired removal of metabolic waste, and ultimately affecting long-term cognitive function. Our results showed that glymphatic system function was temporarily impaired, as evidenced by 2-photon imaging, MRI enhancement, imaging of brain sections, and astrocytic water channel aquaporin 4 (AQP4) protein polarization. The severity of cerebral edema on MRI correlated well with glymphatic system dysfunction within 8 days following SE. Moreover, when cerebral edema was alleviated by glibenclamide treatment or genetic deletion of Trpm4, post-SE glymphatic system function recovered earlier, along with fewer p-tau-deposited neurons and neuronal degeneration and better cognitive function. These findings suggest that SE-induced cerebral edema may cause glymphatic system dysfunction and render the post-SE brain vulnerable to p-tau aggregation and neurocognitive impairment.
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http://dx.doi.org/10.1172/jci.insight.151835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8492308PMC
September 2021

Cathepsin C inhibitors as anti-inflammatory drug discovery: Challenges and opportunities.

Eur J Med Chem 2021 Sep 3;225:113818. Epub 2021 Sep 3.

Engineering Research Center of Biomass Conversion and Pollution Prevention of Anhui Educational Institutions, Fuyang Normal University, Fuyang, 236037, PR China; School of Pharmacy, Anhui Medical University, Hefei, 230032, China. Electronic address:

Cathepsin C, an important lysosomal cysteine protease, mediates the maturation process of neutrophil serine proteases, and participates in the inflammation and immune regulation process associated with polymorphonuclear neutrophils. Therefore, cathepsin C is considered to be an attractive target for treating inflammatory diseases. With INS1007 (trade name: brensocatib) being granted a breakthrough drug designation by FDA for the treatment of Adult Non-cystic Fibrosis Bronchiectasis and Coronavirus Disease 2019, the development of cathepsin C inhibitor will attract attentions from medicinal chemists in the future soon. Here, we summarized the research results of cathepsin C as a therapeutic target, focusing on the development of cathepsin C inhibitor, and provided guidance and reference opinions for the upcoming development boom of cathepsin C inhibitor.
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http://dx.doi.org/10.1016/j.ejmech.2021.113818DOI Listing
September 2021

The genomics of heart failure: design and rationale of the HERMES consortium.

ESC Heart Fail 2021 Sep 3. Epub 2021 Sep 3.

Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.

Aims: The HERMES (HEart failure Molecular Epidemiology for Therapeutic targetS) consortium aims to identify the genomic and molecular basis of heart failure.

Methods And Results: The consortium currently includes 51 studies from 11 countries, including 68 157 heart failure cases and 949 888 controls, with data on heart failure events and prognosis. All studies collected biological samples and performed genome-wide genotyping of common genetic variants. The enrolment of subjects into participating studies ranged from 1948 to the present day, and the median follow-up following heart failure diagnosis ranged from 2 to 116 months. Forty-nine of 51 individual studies enrolled participants of both sexes; in these studies, participants with heart failure were predominantly male (34-90%). The mean age at diagnosis or ascertainment across all studies ranged from 54 to 84 years. Based on the aggregate sample, we estimated 80% power to genetic variant associations with risk of heart failure with an odds ratio of ≥1.10 for common variants (allele frequency ≥ 0.05) and ≥1.20 for low-frequency variants (allele frequency 0.01-0.05) at P < 5 × 10 under an additive genetic model.

Conclusions: HERMES is a global collaboration aiming to (i) identify the genetic determinants of heart failure; (ii) generate insights into the causal pathways leading to heart failure and enable genetic approaches to target prioritization; and (iii) develop genomic tools for disease stratification and risk prediction.
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http://dx.doi.org/10.1002/ehf2.13517DOI Listing
September 2021

Radical-Driven Decomposition of Graphitic Carbon Nitride Nanosheets: Light Exposure Matters.

Environ Sci Technol 2021 09 1;55(18):12414-12423. Epub 2021 Sep 1.

Department of Civil and Environmental Engineering, The George Washington University, Washington, District of Columbia 20052, United States.

Understanding the transformation of graphitic carbon nitride (g-CN) is essential to assess nanomaterial robustness and environmental risks. Using an integrated experimental and simulation approach, our work has demonstrated that the photoinduced hole (h) on g-CN nanosheets significantly enhances nanomaterial decomposition under OH attack. Two g-CN nanosheet samples D and M2 were synthesized, among which M2 had more pores, defects, and edges, and they were subjected to treatments with OH alone and both OH and h. Both D and M2 were oxidized and released nitrate and soluble organic fragments, and M2 was more susceptible to oxidation. Particularly, h increased the nitrate release rate by 3.37-6.33 times even though the steady-state concentration of OH was similar. Molecular simulations highlighted that OH only attacked a limited number of edge-site heptazines on g-CN nanosheets and resulted in peripheral etching and slow degradation, whereas h decreased the activation energy barrier of C-N bond breaking between heptazines, shifted the degradation pathway to bulk fragmentation, and thus led to much faster degradation. This discovery not only sheds light on the unique environmental transformation of emerging photoreactive nanomaterials but also provides guidelines for designing robust nanomaterials for engineering applications.
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http://dx.doi.org/10.1021/acs.est.1c03804DOI Listing
September 2021

Substituent Modulation for Highly Bright 9-Borafluorene Derivatives with Carbazole Pendant.

Org Lett 2021 Sep 31;23(18):7236-7241. Epub 2021 Aug 31.

Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.

A series of 3,6-di--butyl carbazole-functionalized 9-borafluorene derivatives have been prepared with outstandingly strong photoluminescence with quantum yields up to ca. 100 and 94% for in solution and film, respectively. 1,3,5-Tris(trifluoromethyl)benzene (Mes)-substituted compounds exhibit enhanced Lewis acidity with coordination to weak nucleophiles like tetrahydrofuran, resulting in a long afterglow at low temperature. The large two-photon absorption cross-section of ca. 1103 GM for at 800 nm in CHCl indicated its potential application in bioimaging.
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http://dx.doi.org/10.1021/acs.orglett.1c02619DOI Listing
September 2021

Corosolic acid and its structural analogs: A systematic review of their biological activities and underlying mechanism of action.

Phytomedicine 2021 Oct 13;91:153696. Epub 2021 Aug 13.

Research Division of Clinical Pharmacology, the First Affiliated Hospital of Nanjing Medical University & Jiangsu Province Hospital, Nanjing, China; Department of Pharmacy, Jiangsu Shengze Hospital, Nanjing Medical University, Suzhou, China. Electronic address:

Background: The corosolic acid (CA), also known as plant insulin, is a pentacyclic triterpenoid extracted from plants such as Lagerstroemia speciosa. It has been shown to have anti-diabetic, anti-inflammatory and anti-tumor effects. Its structural analogs ursolic acid (UA), oleanolic acid (OA), maslinic acid (MA), asiatic acid (AA) and betulinic acid (BA) display similar individual pharmacological activities to those of CA. However, there is no systematic review documenting pharmacological activities of CA and its structural analogues. This study aims to fill this gap in literature.

Purpose: This systematic review aims to summarize the medical applications of CA and its analogues.

Methods: A systematic review summarizes and compares the extraction techniques, pharmacokinetic parameters, and pharmacological effects of CA and its structural analogs. Hypoglycemic effect is one of the key inclusion criteria for searching Web of Science, PubMed, Embase and Cochrane databases up to October 2020 without language restrictions. 'corosolic acid', 'ursolic acid', 'oleanolic acid', 'maslinic acid', 'asiatic acid', 'betulinic acid', 'extraction', 'pharmacokinetic', 'pharmacological' were used to extract relevant literature. The PRISMA guidelines were followed.

Results: At the end of the searching process, 140 articles were selected for the systematic review. Information of CA and five of its structural analogs including UA, OA, MA, AA and BA were included in this review. CA and its structural analogs are pentacyclic triterpenes extracted from plants and they have low solubilities in water due to their rigid scaffold and hydrophobic properties. The introduction of water-soluble groups such as sugar or amino groups could increase the solubility of CA and its structural analogs. Their biological activities and underlying mechanism of action are reviewed and compared.

Conclusion: CA and its structural analogs UA, OA, MA, AA and BA are demonstrated to show activities in lowering blood sugar, anti-inflammation and anti-tumor. Their oral absorption and bioavailability can be improved through structural modification and formulation design. CA and its structural analogs are promising natural product-based lead compounds for further development and mechanistic studies.
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http://dx.doi.org/10.1016/j.phymed.2021.153696DOI Listing
October 2021

Comprehensive insights into the occurrence, source, distribution and risk assessment of polycyclic aromatic hydrocarbons in a large drinking reservoir system.

Environ Sci Pollut Res Int 2021 Aug 27. Epub 2021 Aug 27.

School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.

The resource, environment, and ecological value of drinking reservoirs have received widespread concerns due to the pollution of persistent organic pollutants such as polycyclic aromatic hydrocarbons (PAHs). Therefore, we comprehensively studied the occurrence, source, distribution, and risk assessment of representative PAHs in Fengshuba Reservoir (FSBR) (large drinking reservoir, China). The total concentrations of 16 USEPA PAHs in the water phase, porewater phase, sediment phase, and soil phase were in ranges of 109.72-393.19 ng/L, 5.75-35.15 μg/L, 364.4-743.71 μg/kg, and 367.81-639.89 μg/kg, respectively. The naphthalene (Nap) was the dominant PAHs in the water phase, while it was Nap and phenanthrene (Phe) in porewater, sediment, and soil phase. The main sources of PAHs in FSBR were biomass combustion. Redundancy analysis indicated that the NTU, NO, NH, Chl-α, and IC were the dominant factors influencing the PAH distribution in water phase, and the PAHs in sediment phase was affected by T and NO. Pseudo-partitioning coefficients indicated that the PAHs in the porewater phase were more likely to migrate to the sediment phase. Risk assessment indicated that the PAHs both in the water and sediment phases were generally in a low-risk state, while the PAHs in the soil phase were in a moderate-risk state, and the Nap was in a high-risk state, and exposure to the PAHs in FSBR through drinking and skin exposure had little impact on consumers' health. In summary, Nap could be used as a key indicator to evaluate the existence and potential risk of PAHs in FSBR.
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http://dx.doi.org/10.1007/s11356-021-16142-0DOI Listing
August 2021
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