Publications by authors named "Xi Tang"

186 Publications

Erratum: usDSM: a novel method for deleterious synonymous mutation prediction using undersampling scheme.

Brief Bioinform 2021 Jun 15. Epub 2021 Jun 15.

GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, China.

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http://dx.doi.org/10.1093/bib/bbab247DOI Listing
June 2021

Tibetan Medicines and Tibetan Prescriptions for the Treatment of Diabetes Mellitus.

Evid Based Complement Alternat Med 2021 17;2021:5532159. Epub 2021 May 17.

School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.

Diabetes mellitus (DM) is one of the most serious diseases threatening human health and because of that, it is imperative to look for drugs to tackle it. The Tibetan medicine, a traditional medical system used in China, is currently being the focus of research towards the discovery of new effective drugs against several diseases. Based on the literature survey of Tibetan medicine monographs and drug standards, the Tibetan medicine, and Tibetan prescription used in the traditional Tibetan medical system, here, we summarise the methods indicated for DM treatment. In the Tibetan medical system, 56 types of Tibetan medicine and 25 Tibetan prescriptions were found for the treatment of DM. The most commonly used are Curcuma, Berberidis Cortex, and Carthami Flos. Their names, families, medicinal parts, phytochemical components, and pharmacological activities were described in detail in our research. These Tibetan medicines and prescriptions are valuable gifts from the Tibetan medicine to the world and may be the source of potential drugs for the treatment of DM. With the help of modern phytochemistry, pharmacology, metabonomics, and/or clinical trial methods, further research is needed to prove its medicinal value, identify bioactive components, elucidate potential mechanisms of action, and assess potential side effects or toxicity. This study provides the first available data compilation for the ethnic medical knowledge of Tibetan medicine for the treatment of DM, providing new ideas and sources for drugs against DM.
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http://dx.doi.org/10.1155/2021/5532159DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8149248PMC
May 2021

Prime-boost vaccination of mice and rhesus macaques with two novel adenovirus vectored COVID-19 vaccine candidates.

Emerg Microbes Infect 2021 Dec;10(1):1002-1015

Department of Transfusion Medicine, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, People's Republic of China.

COVID-19 vaccines are being developed urgently worldwide. Here, we constructed two adenovirus vectored COVID-19 vaccine candidates of Sad23L-nCoV-S and Ad49L-nCoV-S carrying the full-length gene of SARS-CoV-2 spike protein. The immunogenicity of two vaccines was individually evaluated in mice. Specific immune responses were observed by priming in a dose-dependent manner, and stronger responses were obtained by boosting. Furthermore, five rhesus macaques were primed with 5 × 10 PFU Sad23L-nCoV-S, followed by boosting with 5 × 10 PFU Ad49L-nCoV-S at 4-week interval. Both mice and macaques well tolerated the vaccine inoculations without detectable clinical or pathologic changes. In macaques, prime-boost regimen induced high titers of 10 anti-S, 10 anti-RBD binding antibody and 10 pseudovirus neutralizing antibody (pNAb) at 2 months, while pNAb decreased gradually to 10 at 7 months post-priming. Robust T-cell response of IFN-γ (712.6 SFCs/10 cells), IL-2 (334 SFCs/10 cells) and intracellular IFN-γ in CD4/CD8 T cell (0.39%/0.55%) to S peptides were detected in vaccinated macaques. It was concluded that prime-boost immunization with Sad23L-nCoV-S and Ad49L-nCoV-S can safely elicit strong immunity in animals in preparation of clinical phase 1/2 trials.
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http://dx.doi.org/10.1080/22221751.2021.1931466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172228PMC
December 2021

A novel Lnc408 maintains breast cancer stem cell stemness by recruiting SP3 to suppress CBY1 transcription and increasing nuclear β-catenin levels.

Cell Death Dis 2021 05 1;12(5):437. Epub 2021 May 1.

Department of Endocrine and Breast Surgery, The First Affiliated Hospital of Chongqing Medical University, 400016, Chongqing, China.

Tumor initiation, development, and relapse may be closely associated with cancer stem cells (CSCs). The complicated mechanisms underlying the maintenance of CSCs are keeping in illustration. Long noncoding RNAs (lncRNAs), due to their multifunction in various biological processes, have been indicated to play a crucial role in CSC renewal and stemness maintenance. Using lncRNA array, we identified a novel lncRNA (named lnc408) in epithelial-mesenchymal transition-related breast CSCs (BCSCs). The lnc408 is high expressed in BCSCs in vitro and in vivo. The enhanced lnc408 is critical to BCSC characteristics and tumorigenesis. Lnc408 can recruit transcript factor SP3 to CBY1 promoter to serve as an inhibitor in CBY1 transcription in BCSCs. The high expressed CBY1 in non-BCSC interacts with 14-3-3 and β-catenin to form a ternary complex, which leads a translocation of the ternary complex into cytoplasm from nucleus and degradation of β-catenin in phosphorylation-dependent pattern. The lnc408-mediated decrease of CBY1 in BCSCs impairs the formation of 14-3-3/β-catenin/CBY1 complex, and keeps β-catenin in nucleus to promote CSC-associated CD44, SOX2, Nanog, Klf4, and c-Myc expressions and contributes to mammosphere formation; however, restoration of CBY1 expression in tumor cells reduces BCSC and its enrichment, thus lnc408 plays an essential role in maintenance of BCSC stemness. In shortly, these findings highlight that the novel lnc408 functions as an oncogenic factor by recruiting SP3 to inhibit CBY1 expression and β-catenin accumulation in nucleus to maintain stemness properties of BCSCs. Lnc408-CBY1-β-catenin signaling axis might serve as a new diagnostic and therapeutic target for breast cancer.
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http://dx.doi.org/10.1038/s41419-021-03708-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8088435PMC
May 2021

Restoration and risk reduction of lead mining waste by phosphate-enriched biosolid amendments.

Sci Rep 2021 Apr 26;11(1):8965. Epub 2021 Apr 26.

Liaoning Academy of Agriculture Science, Shenyang, 110866, China.

Lead (Pb) contamination in environment has been identified as a threat to human health and ecosystems. In an effort to reduce the health and ecological risks associated with Pb mining wastes, a field study was conducted to stabilize Pb using phosphate (P)-enriched biosolid amendments in the contaminated mining wastes (average of 1004 mg Pb kg) located within the Jasper County Superfund Site, southwest Missouri. Experiments consisted of six biosolid amendment treatments, including Mizzou Doo compost (MD); Spent mushroom compost (SMC); Turkey litter compost (TLC); Composted chicken litter (CCL); Composted sewage sludge (CSS); and Triple superphosphate (TSP). Kentucky tall fescue seeds were planted following the treatments, and soil and plant samples were collected and analyzed 8-10 years post treatment. Results indicated that, in all cases, the biosolid treatments resulted in significant reductions in bioaccessible Pb (96.5 to 97.5%), leachable Pb (95.0 to 97.1%) and plant tissue Pb (45.5 to 90.1%) in the treated wastes, as compared with the control. The treatments had no significantly toxicological effect to soil microbial community. Analysis of the Pb fractionation revealed that the Pb risk reduction was accomplished by transforming labile Pb fractions to relatively stable species through the chemical stabilization reactions as induced by the treatments. The solid-phase microprobe analysis confirmed the formation of pyromorphite or pyromorphite-like minerals after the treatment. Among the six biosolid amendments examined, SMC and MD treatments were shown most effective in the context of Pb stabilization and risk reduction. This field study demonstrated that the treatment effectiveness of Pb stabilization and risk reduction in mining wastes by P-enriched biosolid amendments was long-term and environmental-sound, which could be potentially applied as a cost-effective remedial technology to restore contaminated mining site and safeguard human health and ecosystems from Pb contamination.
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http://dx.doi.org/10.1038/s41598-021-88576-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8076249PMC
April 2021

Mechanism and toxicity evaluation of catalytic ozonation over Cu/Ce-AlO system aiming at degradation of humic acid in real wastewater.

Sci Rep 2021 Apr 22;11(1):8748. Epub 2021 Apr 22.

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China.

Humic acid (HA) is the main component of organic matter in effluent from wastewater treatment. The effective removal of HA is significant. In this study, a novel catalyst was prepared using a transition metal oxide as the active component and AlO as a granular carrier. The mechanism of catalytic ozonation of HA under neutral pH conditions and its efficiency were investigated. Under the chosen conditions (an ozone concentration of 2.2 mg/L, 50 mg/L HA solution, catalyst dosage of 5 g/L and initial pH of 6.49), the Cu/Ce-AlO bimetallic catalyst led to 54.79% TOC removal rate after 30 min; the removal rate by ozone alone was only 20.49%. The characteristics of organic compounds determined by FT-IR and GC-MS showed that organic compounds were degraded significantly by the catalytic treatment. The addition of catalysts could effectively degrade toxic intermediates and reduce the acute toxicity produced by ozonation. Humic acid substances were largely removed and transformed into biodegradable intermediates. This study proposes a new and efficient ozonation catalyst for practical applications in advanced wastewater treatment.
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http://dx.doi.org/10.1038/s41598-021-83804-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062596PMC
April 2021

usDSM: a novel method for deleterious synonymous mutation prediction using undersampling scheme.

Brief Bioinform 2021 Apr 19. Epub 2021 Apr 19.

GMU-GIBH Joint School of Life Sciences, Guangzhou Medical University, China.

Although synonymous mutations do not alter the encoded amino acids, they may impact protein function by interfering with the regulation of RNA splicing or altering transcript splicing. New progress on next-generation sequencing technologies has put the exploration of synonymous mutations at the forefront of precision medicine. Several approaches have been proposed for predicting the deleterious synonymous mutations specifically, but their performance is limited by imbalance of the positive and negative samples. In this study, we firstly expanded the number of samples greatly from various data sources and compared six undersampling strategies to solve the problem of the imbalanced datasets. The results suggested that cluster centroid is the most effective scheme. Secondly, we presented a computational model, undersampling scheme based method for deleterious synonymous mutation (usDSM) prediction, using 14-dimensional biology features and random forest classifier to detect the deleterious synonymous mutation. The results on the test datasets indicated that the proposed usDSM model can attain superior performance in comparison with other state-of-the-art machine learning methods. Lastly, we found that the deep learning model did not play a substantial role in deleterious synonymous mutation prediction through a lot of experiments, although it achieves superior results in other fields. In conclusion, we hope our work will contribute to the future development of computational methods for a more accurate prediction of the deleterious effect of human synonymous mutation. The web server of usDSM is freely accessible at http://usdsm.xialab.info/.
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http://dx.doi.org/10.1093/bib/bbab123DOI Listing
April 2021

Hepatopulmonary syndrome delays postoperative recovery and increases pulmonary complications after hepatectomy.

Eur J Gastroenterol Hepatol 2021 Apr 9. Epub 2021 Apr 9.

Department of Anaesthesiology, Southwest Hospital, Army Medical University, Chongqing Department of Anesthesia, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China LBCMCP, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France Department of Anaesthesiology, Renji Hospital affiliated to Shanghai Jiao Tong University, Shanghai Department of Anaesthesiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.

Background: This study attempted to investigate the impact of hepatopulmonary syndrome (HPS) on postoperative outcomes in hepatitis B virus-induced hepatocellular carcinoma (HBV-HCC) patients.

Methods: HBV-HCC patients undergoing primary curative hepatectomy for HCC in our hospital were diagnosed with HPS by contrast-enhanced echocardiography (CEE) and arterial blood gas analysis. Patients were divided into HPS, intrapulmonary vascular dilation (IPVD) (patients with positive CEE results and normal oxygenation) and control (patients with negative CEE results) groups. Baseline information, perioperative clinical data and postoperative pulmonary complications (PPCs) were compared among all groups. Cytokines in patient serums from each group (n = 8) were also assessed.

Results: Eighty-seven patients undergoing hepatectomy from October 2019 to January 2020 were analyzed. The average time in the postanaesthesia care unit (112.10 ± 38.57 min) and oxygen absorption after extubation [34.0 (14.5-54.5) min] in the HPS group was longer than in IPVD [81.81 ± 26.18 min and 16.0 (12.3-24.0) min] and control [93.70 ± 34.06 min and 20.5 (13.8-37.0) min] groups. There were no significant differences in oxygen absorption time after extubation between HPS and control groups. The incidence of PPCs, especially bi-lateral pleural effusions in the HPS group (61.9%), was higher than in IPVD (12.5%) and control (30.0%) groups. Increased serum levels of the growth-regulated oncogene, monocyte chemoattractant protein, soluble CD40 ligand and interleukin 8 might be related to delayed recovery in HPS patients.

Conclusions: HPS patients with HBV-HCC suffer delayed postoperative recovery and are at higher risk for PPCs, especially bi-lateral pleural effusions, which might be associated with changes in certain cytokines.
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http://dx.doi.org/10.1097/MEG.0000000000002134DOI Listing
April 2021

The application of chimeric deep circumflex iliac artery perforator flap for oromandibular reconstruction: A case report.

Medicine (Baltimore) 2021 Apr;100(14):e25458

Department of Head and Neck Cancer Center.

Rationale: The free fibular flap is considered the gold standard, particularly for a mandibular defect combined with a significant soft tissue defect. However, the fibular flap has the disadvantages of a lack of height for postoperative dental restoration and donor site skin graft if the skin paddle is wider than 5 cm. The larger bone and soft tissue defects tend to be reconstructed using either a scapula or a combination of iliac artery and radial free flap. Few cases involving reconstruction using chimeric deep circumflex iliac artery perforator flap (DCIAPF) for mandibular defect combined with more significant soft tissue defects have been reported due to perforator variations. We successfully performed oromandibular reconstruction using chimeric DCIAPF.

Patient Concerns: A 56-year-old male patient was admitted due to "constant pain in the gradually enlarged right lower gingival mass since the previous four months." The patient had no other obvious symptoms, and no history of diabetes or hypertension was reported. The patient reported long-term smoking and drinking habits.

Diagnoses: Computed tomography (CT) revealed a neoplasm in the right buccal space, which is primarily considered a malignancy. The pathological results of a gingival mass biopsy presented squamous cell carcinoma.

Interventions: No operative contraindications were confirmed after regular tests and examinations were undertaken. The patient underwent a primary extent resection of a 6-cm-long mandible, including mass and suprascapulohyoid neck dissection. The oromandibular defects were then reconstructed with chimeric DCIAPF, simultaneously using the iliac crest bone flap to repair the mandibular lateral segment defect and the skin paddle to repair the intraoral soft tissue defect of 5 × 10 cm.

Outcomes: The total operating time was five and half hours and blood loss was approximately 500 ml. The operation was successful, with no infections or flap loss. Six months postoperatively, CT showed that the iliac crest bone had connected to the alveolar bone of the mandible. The height of the iliac crest bone was sufficient for postoperative dental restoration. The patient healed without obvious complications and no tumor recurrence.

Lessons: Chimeric DCIAPF is an excellent option for mandibular angle or body segment defects combined with significant soft tissue defects.
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http://dx.doi.org/10.1097/MD.0000000000025458DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8036069PMC
April 2021

Hydroxylamine addition enhances fast recovery of anammox activity suffering Cr(VI) inhibition.

Bioresour Technol 2021 Jun 2;329:124920. Epub 2021 Mar 2.

Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha 410083, China.

Hydroxylamine (NHOH), one of the most important intermediates of anammox was employed to test the recovery performance because of its stimulation to anammox bacteria. Batch test indicated simultaneous addition of 1.83 ~ 9.17 mg N /L NHOH relieved Cr(VI) inhibition because of extracellular reduction to Cr(III). The recovery efficiency (RE) was over 166%, with the effluent Cr(VI) and Cr(III) below 0.25 and 0.12 mg/L, respectively. Anammox activity after Cr(VI) inhibition was effectively recovered by 8 mg N/L NHOH with RE at 218%. The long-term operation showed 1 ~ 2 mg N/L NHOH accelerated the recover speed of nitrogen removal rate with 2.84 folds, as well as improving NH conversion ratio and reducing NO production. After 55 days recovery, extracellular polymeric substance concentration, anammox activity and heme content recovered better with NHOH addition. This study will provide the theoretical basis for rapid recovery of anammox activity by NHOH when suffering Cr(VI) inhibition.
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http://dx.doi.org/10.1016/j.biortech.2021.124920DOI Listing
June 2021

Metal-free [3 + 2 + 1] annulation of allylic alcohols, ketones, and ammonium acetate: radical-involving synthesis of 2,3-diarylpyridine derivatives.

Org Biomol Chem 2021 03;19(10):2277-2283

School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China.

A three-component [3 + 2 + 1] annulation strategy for the synthesis of biologically and pharmaceutically active 2,3-diarylpyridine derivatives by using a series of allylic alcohols, ketones, and ammonium acetate as substrates has been developed. The method proceeds efficiently under metal-free conditions, and the desired heterocycles could be obtained in a site-specific selectivity manner with good functional group tolerance.
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http://dx.doi.org/10.1039/d0ob02593cDOI Listing
March 2021

Hsa_circ_0102171 aggravates the progression of cervical cancer through targeting miR-4465/CREBRF axis.

J Cell Physiol 2021 Jul 7;236(7):4973-4984. Epub 2020 Dec 7.

The 5th Ward of Radiotherapy Department of Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, Guangdong, China.

Cervical cancer (CC) has caused numerous cancer-related deaths in women. Recent years, circular RNAs have been reported as vital factors in CC tumorigenesis. Our current study focused on the role of hsa_circ_0102171 (called circ_0102171 subsequently) in CC. At first, we applied reverse transcription polymerase chain reaction to detect the expression of circ_0102171 in CC tissues and cells. Subsequently, we silenced circ_0102171 to conduct loss-of-function assays, including cell counting kit-8 assay, 5-ethynyl-2'-deoxyuridine staining, Transwell assay, and flow cytometry analysis. Interestingly, we discovered that circ_0102171 expressed at a high level in CC tissues and cells. Functionally, silencing circ_0102171 prohibited cell proliferation, migration and invasion, and strengthened cell apoptosis in CC in vitro. Mechanistic investigations revealed that circ_0102171 could act as a sponge for miR-4465. Gain-of-function assays demonstrated that miR-4465 hindered the growth and migration of CC cells. Moreover, circ_0102171 enhanced the level of CREB3 regulatory factor (CREBRF) which was the downstream target of miR-4465. Rescue assays suggested that CREBRF and miR-4465 could involve in circ_0102171-mediated CC progression. Finally, in vivo data supported that silencing circ_0102171 hindered CC cell growth. In conclusion, circ_0102171 aggravates CC progression via targeting miR-4465/CREBRF axis.
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http://dx.doi.org/10.1002/jcp.30210DOI Listing
July 2021

Dose fusion and efficacy evaluation of different radical radiotherapy doses for cervical cancer.

Brachytherapy 2021 May-Jun;20(3):519-526. Epub 2021 Jan 21.

5th Ward of Radiotherapy Department, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, China. Electronic address:

Background: The recommended external beam radiotherapy (EBRT) dose for cervical cancer is 40-50 Gy, but there is no consensus. In this study, 45-Gy and 50.4-Gy treatment groups were compared for fused doses to target tumor areas and organs at risk (OARs), clinical efficacy, and quality of life.

Methods: Seventy-nine cases receiving radical radiotherapy within the past 3 years were retrospectively analyzed. EBRT and three-dimensional brachytherapy dose fusion values were calculated for target areas and OARs using Elastix V5.0. Clinical efficacy was assessed using Response Evaluation Criteria in Solid Tumors (RECIST), adverse events using Common Terminology Criteria for Adverse Events v4.03 (CTCAE4.03), and quality of life using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30).

Results: Minimum fused dose delivered to 90% of the high-risk clinical target volume (HRCTV D90) did not differ significantly between 45-Gy and 50.4-Gy groups, whereas D2cc values of rectum and bladder (OARs) were significantly lower in the 45-Gy group (both p < 0.05). Further analysis showed that these D2cc differences resulted primarily from EBRT. No grade III-IV adverse events were observed in either group during follow up. Short-term clinical efficacy, adverse events, and EORTC QLQ-C30 functional and symptom scales also did not differ significantly between groups (all p > 0.05). However, quality of life was markedly higher in the 45-Gy group (p < 0.05).

Conclusion: Appropriate EBRT dose reduction can reduce OAR irradiation without compromising total target area dose or clinical efficacy. Dose fusion can facilitate the judicious choice of EBRT to limit OAR exposure, reduce adverse events, and enhance the quality of life.
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http://dx.doi.org/10.1016/j.brachy.2020.12.001DOI Listing
January 2021

Role of core protein mutations in the development of occult HBV infection.

J Hepatol 2021 Jun 13;74(6):1303-1314. Epub 2021 Jan 13.

Department of Transfusion Medicine, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China. Electronic address:

Background & Aims: Occult HBV infection (OBI) is associated with transfusion-transmitted HBV infection and hepatocellular carcinoma. Studies on OBI genesis have concentrated on mutations in the S region and the regulatory elements. Herein, we aimed to determine the role of mutations in the core region on OBIs.

Methods: An OBI strain (SZA) carrying 9 amino acid (aa) substitutions in the core protein/capsid (Cp) was selected by sequence alignment and Western blot analysis from 26 genotype B OBI samples to extensively explore the impact of Cp mutations on viral antigen production in vitro and in vivo.

Results: A large panel of 30 Cp replicons were generated by a replication-competent pHBV1.3 carrying SZA or wild-type (WT) Cp in a 1.3-fold over-length of HBV genome, in which the various Cp mutants were individually introduced by repairing site mutations of SZA-Cp or creating site mutations of WT-Cp by site-directed mutagenesis. The expression of HBcAg, HBeAg, and HBsAg and viral RNA was quantified from individual SZA and WT Cp mutant replicons in transfected Huh7 cells or infected mice, respectively. An analysis of the effect of Cp mutants on intracellular or extracellular viral protein production indicated that the W62R mutation in Cp had a critical impact on the reduction of HBcAg and HBeAg production during HBV replication, whereas P50H and/or S74G mutations played a limited role in influencing viral protein production invivo.

Conclusions: W62R and its combination mutations in HBV Cp might massively affect HBcAg and HBeAg production during viral replication, which, in turn, might contribute to the occurrence of OBI.

Lay Summary: Occult hepatitis B virus infections (OBIs) have been found to be associated with amino acid mutations in the S region of the HBV, but the role of mutations in the core protein (Cp) remains unclear. In this study, an OBI strain (SZA) carrying 9 amino acid substitutions in Cp has been examined comprehensively in vitro and in vivo. The W62R mutation in Cp majorly reduces HBcAg and HBeAg production during HBV replication, potentially contributing to the occurrence of OBI.
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http://dx.doi.org/10.1016/j.jhep.2020.12.023DOI Listing
June 2021

Deciphering bacterial social traits via diffusible signal factor (DSF) -mediated public goods in an anammox community.

Water Res 2021 Mar 2;191:116802. Epub 2021 Jan 2.

College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; International Joint Laboratory for Regional Pollution Control, Ministry of Education of China, Beijing 100871, China. Electronic address:

Both the benefits of bacterial quorum sensing (QS) and cross-feeding for bio-reactor performance in wastewater treatment have been recently reported. As the social traits of microbial communities, how bacterial QS regulating bacterial trade-off by cross-feeding remains unclear. Here, we find diffusion signal factor (DSF), a kind of QS molecules, can bridge bacterial interactions through regulating public goods (extracellular polymeric substances (EPS), amino acids) for metabolic cross-feedings. It showed that exogenous DSF-addition leads to change of public goods level and community structure dynamics in the anammox consortia. Approaches involving meta-omics clarified that anammox and a Lautropia-affiliated species in the phylum Proteobacteria can supply costly public goods for DSF-Secretor species via secondary messenger c-di-GMP regulator (Clp) after sensing DSF. Meanwhile, DSF-Secretor species help anammox bacteria scavenge extracellular detritus, which creates a more suitable environment for the anammox species, enhances the anammox activity, and improves the nitrogen removal rate of anammox reactor. The trade-off induces discrepant metabolic loads of different microbial clusters, which were responsible for the community succession. It illustrated the potential to artificially alleviate metabolic loads for certain bacteria. Deciphering microbial interactions via QS not only provides insights for understanding the social behavior of microbial community, but also creates new thought for enhancing treatment performance through regulating bacterial social traits via quorum sensing-mediated public goods.
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http://dx.doi.org/10.1016/j.watres.2020.116802DOI Listing
March 2021

Development and simulation of a struvite crystallization fluidized bed reactor with enhanced external recirculation for phosphorous and ammonium recovery.

Sci Total Environ 2021 Mar 8;760:144311. Epub 2020 Dec 8.

Key Lab of Water Pollution Control Technology of Hunan Province, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China. Electronic address:

Recovering nitrogen and phosphorus from waste water in the form of struvite is an effective way to recycle resources. The insufficient purity of the resulting struvite and the large loss of nitrogen and phosphorus are the challenges at present. Therefore, it is urgent to develop innovative method in struvite crystallization process for efficient nitrogen and phosphorus recovery. This study proposed a crystallization method to reduce the loss of nitrogen and phosphorus by a struvite fluidized bed reactor (FBR) with optimized structure and operation conditions. The properties of struvite obtained under various conditions in the reactor were studied, and the internal operating conditions of the reactor were simulated with COMSOL Multiphysics to verify the effectiveness of the reactor optimization. This reactor achieved stable operation under the conditions of N/P = 1:1 and pH = 9.0. The purity of struvite obtained reached 98.5%, the conversion rate of ammonia nitrogen reached 97.2%, and struvite crystals could grow to 84 μm within 24 h. The simulation results showed that the Venturi tubes installed at multiple locations increased the turbulent energy to 4 × 10 m/s, which greatly improved the mass transfer efficiency. The trajectory of the crystal particles was consistent with the fluid flow field, which promoted the purification and growth of the crystal. In general, the new FBR with enhanced external recirculation would be a very feasible way to improve crystal growth and crystal purification of struvite, and it could enhance the recovery efficiency of nitrogen and phosphorus with reduced cost.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144311DOI Listing
March 2021

Salivary microbiome in patients undergoing hemodialysis and its associations with the duration of the dialysis.

BMC Nephrol 2020 09 29;21(1):414. Epub 2020 Sep 29.

State Key Laboratory of Oral Diseases & National Clinical Research Centre for Oral Diseases, West China Hospital of Stomatology, Sichuan University, No. 14, Section 3, Renmin South Road, Chengdu, 610041, Sichuan, China.

Background: Chronic kidney disease (CKD) patients, especially those with end stage renal disease (ESRD) undergoing hemodialysis (HD), exhibit high prevalence of periodontitis. This cross-sectional study aimed to investigate the periodontal status of HD patients and its relationship with salivary microbiome.

Methods: One hundred eight HD patients and one hundred healthy control individuals were recruited. They were subjected to periodontal examination followed by saliva samples collection for 16S rRNA gene sequencing.

Results: The HD patients were with worse periodontal health status, and exhibited higher salivary microbial diversity and lower richness. The periodontal pathogens were significantly enriched in the HD patients. The inferred functional analyze showed microbes enriched in the HD patients were mainly related to metabolism. Despite the periodontal status and overall structure of the microbiome were not significantly altered as the HD duration prolonged, the abundance of Lachnospiraceae [G-2] sp. |HMT_096| is positively correlated with the duration of HD and the community periodontal index (CPI). Five OTUs (operational taxonomic units) belonging to the phyla Firmicutes were enriched as the duration prolonged, and four OTUs originated from the phyla Proteobacteria were negatively related with the CPI index. ESRD patients undergoing HD exhibited microbiota structural, compositional and functional differences compared with the healthy controls. And the species changed as the duration of hemodialysis prolonged.

Conclusions: End stage renal disease changes salivary microbiome and is a risk factor for oral dysbiosis.
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http://dx.doi.org/10.1186/s12882-020-02009-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7523083PMC
September 2020

The kinetics of viral load and antibodies to SARS-CoV-2.

Clin Microbiol Infect 2020 Dec 6;26(12):1690.e1-1690.e4. Epub 2020 Sep 6.

Guangdong Provincial Centre for Disease Control and Prevention, Guangzhou, China. Electronic address:

Objectives: The aim was to understand persistence of the virus in body fluids the and immune response of an infected host to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), an agent of coronavirus disease 2019 (COVID-19).

Methods: We determined the kinetics of viral load in several body fluids through real time reverse transcription polymerase chain reaction, serum antibodies of IgA, IgG and IgM by enzyme-linked immunosorbent assay and neutralizing antibodies by microneutralization assay in 35 COVID-19 cases from two hospitals in Guangdong, China.

Results: We found higher viral loads and prolonged shedding of virus RNA in severe cases of COVID-19 in nasopharyngeal (1.3 × 10 vs 6.4 × 10, p < 0.05; 7∼8 weeks) and throat (6.9 × 10 vs 2.9 × 10, p < 0.05; 4∼5 weeks), but similar in sputum samples (5.5 × 10 vs 0.9 × 10, p < 0.05; 4∼5 weeks). Viraemia was rarely detected (2.8%, n = 1/35). We detected early seroconversion of IgA and IgG at the first week after illness onset (day 5, 5.7%, n = 2/35). Neutralizing antibodies were produced in the second week, and observed in all 35 included cases after the third week illness onset. The levels of neutralizing antibodies correlated with IgG (r = 0.85, p < 0.05; kappa = 0.85) and IgA (r = 0.64, p < 0.05; kappa = 0.61) in severe, but not mild cases (IgG, r = 0.42, kappa = 0.33; IgA, r = 0.32, kappa = 0.22). No correlation with IgM in either severe (r = 0.17, kappa = 0.06) or mild cases (r = 0.27, kappa = 0.15) was found.

Discussion: We revealed a prolonged shedding of virus RNA in the upper respiratory tract, and evaluated the consistency of production of IgG, IgA, IgM and neutralizing antibodies in COVID-19 cases.
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http://dx.doi.org/10.1016/j.cmi.2020.08.043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7474805PMC
December 2020

Glomerular C4 deposition and glomerulosclerosis predict worse renal outcomes in Chinese patients with IgA nephropathy.

Ren Fail 2020 Nov;42(1):629-637

Division of Nephrology, West China Hospital, Kidney Research Institute, Sichuan University, Chengdu, P.R. China.

Background: Immunoglobulin A nephropathy (IgAN) is a clinical and pathological syndrome with heterogenous manifestation and progression. Complement activation is involved in the disease. However, the clinical significance of C4 deposition in IgAN is obscure.

Methods: A multicenter retrospective study was conducted in biopsy-proven IgAN patients. Based on mesangial C4 deposition, patients were divided into two groups. The baseline clinical data and immunopathological phenotypes were compared. The composite endpoint was defined as eGFR decline greater than 50%, doubling of baseline serum creatinine, the occurrence of end-stage renal disease (ESRD).

Results: A total of 642 IgAN patients were recruited, with 41 patients showing mesangial C4 deposition. The mesangial C4 positive group showed lower serum albumin, higher proteinuria, and a higher rate of IgG, IgM, and C1q mesangial deposition. After a median follow-up of 43.18 months, 81 (12.62%) patients achieved the composite endpoint. The multivariate Cox regression models identified glomerular C4 deposition (hazard ratios [HR] = 3.22, 95% confidence intervals [CI] = 1.51-6.87,  < 0.01), global sclerosis (G1 vs. G0, HR = 1.90, 95%CI = 1.02-3.52,  = 0.04; G2 vs. G0, HR = 3.72, 95%CI = 1.98-7.00,  < 0.01), male (HR = 1.80, 95%CI = 1.10-2.97,  = 0.02), serum creatinine (HR = 1.01, 95%CI = 1.00-1.01,  < 0.01), triglyceride (HR = 1.17, 95%CI = 1.01-1.35,  = 0.04), proteinuria (HR = 1.07, 95%CI = 1.01-1.13,  = 0.02), serum C3 level (HR = 0.05, 95%CI = 0.01-0.25,  < 0.01), and serum C4 level (HR = 99.59, 95%CI = 8.69-1140.89,  < 0.01) as independent risk factors for poor renal outcomes.

Conclusions: Glomerular mesangial C4 deposition and global sclerosis are independent predictors for poor prognosis in IgAN patients.
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http://dx.doi.org/10.1080/0886022X.2020.1786400DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7470092PMC
November 2020

Metabolic acclimation of anammox consortia to decreased temperature.

Environ Int 2020 10 8;143:105915. Epub 2020 Jul 8.

Department of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, Qinghai, China. Electronic address:

Widespread application of anammox process has been primarily limited to the high sensitivity of anammox consortia to fluctuations of temperature. However, the metabolic acclimation of anammox consortia to decreased temperature remains unclear, which is the core of developing potential strategies for improving their low-temperature resistance. Here, we operated anammox reactors at 25 °C and 35 °C to explore the acclimation mechanism of anammox consortia in terms of metabolic responses and cross-feedings. Accordingly, we found that the adaptation of anammox consortia to ambient temperature (25 °C) was significantly linked to energy conservation strategy, resulting in decreased extracellular polymeric substance secretion, accumulation of ATP and amino acids. The expression patterns of cold shock proteins and core enzymes caused the apparent metabolic advantage of Candidatus Brocadia fulgida for acclimation to ambient temperature compared to other anammox species. Importantly, strengthened cross-feedings of amino acids, nitrite and glycine betaine benefited adaptation of anammox consortia to ambient temperature. Our work not only uncovers the temperature-adaptive mechanisms of anammox consortia, but also emphasizes the important role of metabolic cross-feeding in the temperature adaptation of microbial community.
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http://dx.doi.org/10.1016/j.envint.2020.105915DOI Listing
October 2020

A Phase II Trial of Alisertib (MLN8237) in Salvage Malignant Mesothelioma.

Oncologist 2020 10 19;25(10):e1457-e1463. Epub 2020 Jul 19.

Department of Thoracic/Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.

Lessons Learned: Treatment with the Aurora kinase A inhibitor yields often durable disease control, but limited tumor regression, in heavily pretreated patients with unresectable malignant pleural or peritoneal mesothelioma. In a limited sample size, MYC copy-number gain or gene amplification, a candidate predictive biomarker for alisertib, did not correlate with improved response numbers or patient outcomes.

Background: Malignant mesothelioma is an aggressive disease for which few effective therapies are available. The Aurora family kinases are critical for mitotic fidelity and highly expressed in mesothelioma, wherein their inhibition leads to growth arrest in vitro. We evaluated the efficacy of alisertib, an Aurora A kinase inhibitor, in relapsed malignant mesothelioma.

Methods: Twenty-six patients with previously treated, unresectable pleural or peritoneal mesothelioma were enrolled on a single-arm, single-institution phase II trial of alisertib at a dosage of 50 mg twice daily for 7 of every 21 days. The primary endpoint was 4-month disease control rate. Secondary endpoints included overall response rate, progression free survival, overall survival, safety/toxicity, and correlation of endpoints with MYC copy number.

Results: Of the 25 evaluable patients treated on study, 8 (32%) experienced 4-month disease control, surpassing the futility endpoint. There were no confirmed partial or complete responses. Median progression-free and overall survival were 2.8 months and 6.3 months, respectively. No associations between MYC copy number and outcomes were observed.

Conclusion: Alisertib has modest activity in this unselected malignant mesothelioma population. Several patients achieved durable disease control. Although the study did meet its prespecified futility endpoint, the sponsor elected to close the trial at the interim analysis.
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http://dx.doi.org/10.1634/theoncologist.2020-0610DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7543335PMC
October 2020

An 'asymptomatic' driver with COVID-19: atypical suspected myocarditis by SARS-CoV-2.

Cardiovasc Diagn Ther 2020 Apr;10(2):242-243

Department of Radiology, The Second Affiliated Hospital of Kunming Medical University, Kunming 650101, China.

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http://dx.doi.org/10.21037/cdt.2020.03.08DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7225419PMC
April 2020

Prolonged Persistence of SARS-CoV-2 RNA in Body Fluids.

Emerg Infect Dis 2020 08 8;26(8):1834-1838. Epub 2020 May 8.

We prospectively assessed 49 coronavirus disease cases in Guangdong, China, to estimate the frequency and duration of detectable severe acute respiratory syndrome coronavirus 2 RNA in human body fluids. The prolonged persistence of virus RNA in various body fluids may guide the clinical diagnosis and prevention of onward virus transmission.
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http://dx.doi.org/10.3201/eid2608.201097DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7392422PMC
August 2020

Genomic Epidemiology of SARS-CoV-2 in Guangdong Province, China.

Cell 2020 05 30;181(5):997-1003.e9. Epub 2020 Apr 30.

Guangzhou Center for Disease Control and Prevention, Guangzhou 510440, China.

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 infection and was first reported in central China in December 2019. Extensive molecular surveillance in Guangdong, China's most populous province, during early 2020 resulted in 1,388 reported RNA-positive cases from 1.6 million tests. In order to understand the molecular epidemiology and genetic diversity of SARS-CoV-2 in China, we generated 53 genomes from infected individuals in Guangdong using a combination of metagenomic sequencing and tiling amplicon approaches. Combined epidemiological and phylogenetic analyses indicate multiple independent introductions to Guangdong, although phylogenetic clustering is uncertain because of low virus genetic variation early in the pandemic. Our results illustrate how the timing, size, and duration of putative local transmission chains were constrained by national travel restrictions and by the province's large-scale intensive surveillance and intervention measures. Despite these successes, COVID-19 surveillance in Guangdong is still required, because the number of cases imported from other countries has increased.
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http://dx.doi.org/10.1016/j.cell.2020.04.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7192124PMC
May 2020

Novel hepatitis B virus surface antigen mutations associated with occult genotype B hepatitis B virus infection affect HBsAg detection.

J Viral Hepat 2020 09 11;27(9):915-921. Epub 2020 May 11.

Department of Transfusion Medicine, School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China.

The causative factors of occult hepatitis B infection are complicated and not yet been fully elucidated. Mutations in hepatitis B virus (HBV) S gene are one of the factors may contributing to occult infection. In this study, 89 blood donors with genotype B occult HBV infection were investigated. Fifty-seven hepatitis B surface antigen (HBsAg)-positive/HBV DNA-positive blood donors served as control group for comparison. Occult HBV-related mutations with a high incidence (P < .05) in the S gene were identified. To further verify these occult infection-related mutations, a conservative full-gene expression vector of HBV B genotype (pHBV1.3B) was constructed. Then, the mutant plasmids on the basis of pHBV1.3B were constructed and transfected into HepG2 cells. Extracellular as well as intracellular HBsAg was analysed by electrochemical luminescence and cellular immunohistochemistry. Ten occult infection-related mutations (E2G, Q101R, K122R, M133T, D144E, G145R, V168A, S174N, L175S and I226S) were significantly more frequent in the occult infection group (P < .05). Five of the ten mutations (E2G, D144E, G145R, V168A and S174N) strongly decreased extracellular HBsAg level (P < .05) in the transfection system. Notably, the E2G mutation had the most significant impact on the ratio of extracellular HBsAg (3.8% vs pHBV1.3B) and intracellular HBsAg (239.3% vs pHBV1.3B) (P < .05), and the fluorescence density of E2G mutant HBsAg was significantly higher than that of pHBV1.3B (P < .0001). Hence, ten mutations were associated with genotype B occult HBV infection; E2G and V168A were novel mutations which we confirmed significantly affect HBsAg detection. E2G might cause HBsAg secretion impairment that results in intracellular accumulation and a decrease in HBsAg secretion.
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http://dx.doi.org/10.1111/jvh.13309DOI Listing
September 2020

LINC02535 co-functions with PCBP2 to regulate DNA damage repair in cervical cancer by stabilizing RRM1 mRNA.

J Cell Physiol 2020 10 23;235(10):7592-7603. Epub 2020 Apr 23.

The 5th Ward of Radiotherapy Department of Affiliated Cancer Hospital, Institute of Guangzhou Medical University, Guangzhou, Guangdong, China.

Cervical cancer (CC) is one of the commonest malignant cancers among women with high morbidity and mortality. Despite encouraging advances had been found in diagnostic and therapeutic strategies, effective therapeutic strategy and further exploration of the mechanism underlying in CC is still needed. We searched The Cancer Genome Atlas database and found that long noncoding RNA LINC02535 was highly expressed in CC. LINC02535 has not been studied in CC, and its molecular regulation mechanism remains unknown. Based on starBase database, LINC02535 could potentially bind poly (rC) binding protein 2 (PCBP2). In the present study, we discovered a significant increase of the LINC02535 and PCBP2 expression in CC tissues and cells as compared with the adjacent normal tissues and normal cervical epithelial cells. LINC02535 and PCBP2 can bind with each other and were colocated in cytoplasm. LINC02535 and PCBP2 promoted cell proliferation, migration, invasion, and suppressed apoptosis in CC. LINC02535 and PCBP2 facilitated the repair of DNA damage to promote CC progression. LINC02535 cooperated with PCBP2 to enhance the stability of RRM1 messenger RNA (mRNA). RRM1 promoted the repair of DNA damage and epithelial-to-mesenchymal transition (EMT) process in CC cells. LINC02535 regulated tumorigenesis in vivo. In conclusion, LINC02535 cooperated with PCBP2, regulated stability of RRM1 mRNA to promote cell proliferation and EMT process in CC cells by facilitating the repair of DNA damage, providing a potential biomarker for CC.
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http://dx.doi.org/10.1002/jcp.29667DOI Listing
October 2020

Optical Trapping with Focused Surface Waves.

Ann Phys 2020 Apr 24;532(4). Epub 2020 Feb 24.

Department of Optics and Optical Engineering, Institute of Photonics, University of Science and Technology of China, Hefei, Anhui 230026, China.

Near-field optical trapping can be realized with focused evanescent waves that are excited at the water-glass interface due to the total internal reflection, or with focused plasmonic waves excited on the water-gold interface. Herein, the performance of these two kinds of near-field optical trapping techniques is compared using the same optical microscope configuration. Experimental results show that only a single-micron polystyrene bead can be trapped by the focused evanescent waves, whereas many beads are simultaneously attracted to the center of the excited region by focused plasmonic waves. This difference in trapping behavior is analyzed from the electric field intensity distributions of these two kinds of focused surface waves and the difference in trapping behavior is attributed to photothermal effects due to the light absorption by the gold film.
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http://dx.doi.org/10.1002/andp.201900497DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8189021PMC
April 2020

Performance, microbial community and inhibition kinetics of long-term Cu stress on an air-lift nitritation reactor with self-recirculation.

J Environ Sci (China) 2020 May 6;91:117-127. Epub 2020 Feb 6.

Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha, 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha, 410083, China.

Biological nitrogen removal process could be affected due to the presence of heavy metals owing to their toxicity and accumulation in the sludge. In this study, the impact of Cu shock on a long-term nitritation operation was investigated in an air-lift reactor with self-recirculation. Both the dynamics of microbial community and inhibition kinetics under Cu stress were ascertained. The results showed that Cu exerted severe inhibition on nitritation performance of an air-lift reactor (ALR) at 25 mg/L. The corresponding NH-N removal efficiency decreased to below 50%, which was mainly due to the variation of microbial community structure, especially the inhibition of nitrifiers like Nitrosomonas (the relative abundance decreased from 30% to 1% after Cu inhibition). Kinetic parameters were obtained and compared after fitting the Haldane model. The long-term Cu stress on the ALR aggravated the ammonium affinity and the resistance to substrate self-inhibition of the nitritation sludge, but reduced the resistance to Cu inhibition. Furthermore, Cu acted as uncompetitive inhibitor on nitritation process. Our results provide new insights into the nitritation characteristics under long-term Cu stress.
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http://dx.doi.org/10.1016/j.jes.2020.01.021DOI Listing
May 2020

Quantitative determination of cavitation formation and sludge flotation in Anammox granules by using a new diffusion-reaction integrated mathematical model.

Water Res 2020 May 19;174:115632. Epub 2020 Feb 19.

Department of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha, 410083, China; National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution, Changsha, 410083, China. Electronic address:

The granulation of anaerobic ammonium oxidation (Anammox) biomass plays a key role in high rate performance of upflow-type Anammox reactors. However, the formation of cavitation inside granules may result in sludge flotation problem, which negatively affects the operation stability. For quantitative evaluation of the Anammox granules flotation in upflow reactors, an integrated mathematical model was formulated based on the principles that the limitation of substrate diffusion would result in bacterial starvation, lysis and subsequently aiding the formation of cavitation in the inner zone of granules. The proposed model is used to investigate the possible mechanism of cavitation formation and granules flotation. The combined modelling and experimental results showed that the model predictions matched well with the actual floating behavior of granules (R = 0.83 for settled sludge and 0.76 for floating sludge). Based on the model results, the granule flotation could be divided into three zones namely (i) no-flotation zone (no flotation occurrence), (ii) transition zone (flotation with a part of granules), and (iii) flotation zone (inevitable flotation occurrence). The floating behavior of granules was mainly influenced by granule diameter (2.5-4.5 mm) and substrate concentration (NO-N, 50-250 mg/L) in the transition zone. The optimum granule diameter to avoid flotation but with excellent settling performance was identified around 2.5 mm. Additionally, the granule size is more sensitivity to flotation than substrate concentration. Hence, controlling the size of granules is more important to alleviate granule flotation in Anammox reactors' operation.
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http://dx.doi.org/10.1016/j.watres.2020.115632DOI Listing
May 2020

The regulation of nitric oxide in tumor progression and therapy.

J Int Med Res 2020 Feb;48(2):300060520905985

Department of Oncology, Jingzhou Central Hospital, Jingzhou, Hubei, P. R. China.

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http://dx.doi.org/10.1177/0300060520905985DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7110915PMC
February 2020
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