Publications by authors named "Hong Du"

423 Publications

Identification of a phage-derived depolymerase specific for KL64 capsule of Klebsiella pneumoniae and its anti-biofilm effect.

Virus Genes 2021 Jun 22. Epub 2021 Jun 22.

College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.

The increasing prevalence of Carbapenem-resistant Klebsiella pneumoniae (CRKP) poses a serious threat to global health. Phages and phage-derived enzymes gained increasing attention for controling CRKP infections. In this study, a lytic phage P510 infecting KL64 type K. pneumoniae was isolated and characterized. Whole genome analysis and electron microscopy analysis showed that phage P510 belonged to genus Przondovirus, family Autographiviridae, the order Caudovirales. The tail fiber protein of the phage was predicted to encode capsule depolymerase. Further analysis demonstrated that recombinant depolymerase P510dep had polysaccharide-degrading activity against KL64-types capsule of K. pneumoniae, and its lysis spectrum matched to host range of phage P510. We also demonstrated that the recombinant depolymerase was able to significantly inhibit biofilm formation. The discovery of the phage-derived depolymerase lays the foundation for controlling the spread of CRKPs.
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http://dx.doi.org/10.1007/s11262-021-01847-8DOI Listing
June 2021

Construction of an autophagy interaction network based on competitive endogenous RNA reveals the key pathways and central genes of SARS-CoV-2 infection in vivo.

Microb Pathog 2021 Jun 18:105051. Epub 2021 Jun 18.

Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address:

As of April 1, 2021, more than 2.8 million people have died of SARS-CoV-2 infection. In addition, the mutation of virus strains that have accompanied the pandemic has brought more severe challenges to pandemic control. Host microRNAs (miRNAs) are widely involved in a variety of biological processes of coronavirus infection, including autophagy in SARS-CoV-2 infection. However, the mechanisms underlying miRNAs involved in autophagy in SARS-CoV-2 infection have not been fully elucidated. In this study, the miRNA and messenger RNA (mRNA) expression profiles of patients with SARS-CoV-2 infection were investigated based on raw data from Gene Expression Omnibus (GEO) datasets, and potential novel biomarkers of autophagy were revealed by bioinformatics analyses. We identified 32 differentially expressed miRNAs and 332 differentially expressed mRNAs in patients with SARS-CoV-2 infection. Cytokine receptor related pathways were the most enriched pathways for differentially expressed miRNAs identified by pathway analysis. Most importantly, an autophagy interaction network, which was associated with the pathological processes of SARS-CoV-2 infection, especially with the cytokine storm, was constructed. In this network, hsa-miR-340-3p, hsa-miR-652-3p, hsa-miR-4772-5p, hsa-miR-192-5p, TP53INP2, and CCR2 may be biomarkers that predict changes in mild SARS-CoV-2 infection. Some molecules, including hsa-miR-1291 and CXCR4, were considered potential targets to predict the emergence of severe symptoms in SARS-CoV-2 infection. To our knowledge, this study provided the first profile analysis of an autophagy interaction network in SARS-CoV-2 infection and revealed several novel autophagy-related biomarkers for understanding the pathogenesis of SARS-CoV-2 infection in vivo.
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http://dx.doi.org/10.1016/j.micpath.2021.105051DOI Listing
June 2021

Emergence and genomics of OXA-232-Producing Klebsiella pneumoniae in a hospital, Yancheng, China.

J Glob Antimicrob Resist 2021 Jun 16. Epub 2021 Jun 16.

Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China. Electronic address:

Objectives: This study aims to infer phylogenetic relationship of OXA-232-producing Klebsiella pneumoniae (OXA232Kp) strains collected from a Chinese hospital, and to determine the composition and genetic background of antimicrobial resistance genes (ARGs) among these strains.

Methods: A total of three non-duplicated OXA232Kp strains were collected from a Chinese hospital. Whole genome sequencing (WGS) was used to determined their genome sequences, and then a genomic comparison of ARG-carrying genetic elements from these three strains with related sequences were performed. Phylogenetic analysis was conducted by constructing maximum-likelihood phylogenetic tree.

Results: Compared with other Chinese sequence type 15 (ST15)-OXA232Kp strains, three ST15-OXA232Kp strains in this study could be divided into a single subgroup in phylogenetic relationship. The composition and genetic background of ARGs were identical in these three strains. A total of three ARG-carrying genetic elements or multidrug resistance (MDR) regions were determined, including a truncated Tn2013-like IS-based transposition unit, a unit transposition Tn6867b and a 40.9-kb MDR region.

Conclusions: This study reported a clonal dissemination of ST15-OXA232Kp strains carrying multiple ARGs in a Chinese hospital. A comprehensive evolutionary and genomic analysis gained a deeper understanding of OXA232Kp. Further surveillance and study should be advocated to prevent the dissemination of OXA232Kp strains in China.
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http://dx.doi.org/10.1016/j.jgar.2021.05.015DOI Listing
June 2021

MicroRNA-135b/CAMK2D Axis Contribute to Malignant Progression of Gastric Cancer through EMT Process Remodeling.

Int J Biol Sci 2021 10;17(8):1940-1952. Epub 2021 May 10.

Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital, Fu-Cheng Road, Beijing, 100142, China.

There is a continued need for investigating the roles of microRNAs (miRNAs) and their targets on the progression of gastric cancer (GC), especially metastasis. Here, we performed an integrated study to identify dysregulated miRNAs critical for GC development and progression. miR-135b was determined as a promising biomarker for GC. The expression level of miR-135b was increased among GC cell lines, patient tumor tissues, serum samples, and correlation with aggravation of the GC patients. The functional assays demonstrated overexpression of miR-135b promoted cell proliferation, migration and invasion in GC, while miR-135b inhibition led to the opposite results. CAMK2D was found to be the direct target of miR-135b, serving as a tumor suppressor in GC cells. Based on our and public datasets, we confirmed the attenuation of CAMK2D expression in GC tissues. And, the expression levels of miR-135b and CAMK2D were closely associated with prognosis of GC patients. Ectopic expression of miR-135b resulted in the down-regulation of CAMK2D. Additionally, CAMK2D was a prerequisite for miR-135b to promote GC cells proliferation and migration by regulating the EMT process, which was confirmed by the experiments. Importantly, injection of miR-135b antagomir significantly repressed the tumor growth and metastasis of xenograft models, which suggested that the miR-135b antagomir were promising for clinical applications. Taken together, these results indicate that miR-135b/CAMK2D axis drives GC progression by EMT process remodeling, suggesting that miR-135b may be utilized as a new therapeutic target and prognostic marker for GC patients.
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http://dx.doi.org/10.7150/ijbs.58062DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8193265PMC
May 2021

Effect of hydroxyethyl cellulose soluble hemostatic gauze on hemostasis in facial contouring surgery.

Medicine (Baltimore) 2021 May;100(19):e25847

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Shijingshan District, Beijing, China.

Background: In facial contour surgery, due to the narrow field of vision in the oral approach and the abundant blood supply to the maxillofacial area, hemostasis is not easy. The purpose of this study was to evaluate the hemostatic effect of soluble hemostatic gauze.

Methods: We organized a prospective randomized study of 282 patients receiving facial contouring surgery (4 types of procedures in total) during 2016.1.1 to 2018.12.30. For each type of procedure, patients were randomly divided into study group (received hemostatic gauze) and control group (received sterile gauze). Two groups were compared for each type of procedure regarding 5 major perioperative variables: intraoperative blood loss, operation time, 24-hour postoperative drainage volume, total postoperative drainage volume, and postoperative drainage time. Correlation between variables was analyzed.

Results: Compared with control group, the study group had higher amount of intraoperative blood loss in mandibular angle ostectomy (MAO) (P < .01) and mandibular angle-body-chin curved ostectomy procedures (P < .05), less total postoperative drainage volume in MAO (P < .01) but not in malarplasty with MAO and partial masseter muscle resection along with MAO procedures. No significant difference was observed between respective study and control groups regarding operation time, 24-hour postoperative drainage volume, and postoperative drainage time in any of the 4 types of surgery. In all 4 types of procedures, a strongly positive correlation was observed between total drainage volume and 24-hour drainage volume in both the study and control groups (r: 0.88-0.97, P < .01).

Conclusion: The effect of hydroxyethyl cellulose soluble hemostatic gauze on hemostasis in facial contouring surgery is associated with the type of surgery, which can reduce the risk of postoperative bleeding in MAO. However, for surgery with relatively large amount of intraoperative and postoperative bleeding, the hemostatic gauze had a limited postoperative hemostasis efficacy, which needs further evaluation.
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http://dx.doi.org/10.1097/MD.0000000000025847DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8133102PMC
May 2021

Correction to: Reduction Mandibuloplasty Along with Partial Masseter Muscle Resection: Masseter Muscle Response and Bone Regeneration.

Aesthetic Plast Surg 2021 Jun 8. Epub 2021 Jun 8.

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144, China.

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http://dx.doi.org/10.1007/s00266-021-02410-4DOI Listing
June 2021

Reduction Mandibuloplasty Along with Partial Masseter Muscle Resection: Masseter Muscle Response and Bone Regeneration.

Aesthetic Plast Surg 2021 May 24. Epub 2021 May 24.

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100144, China.

Objective: To compare the masseter muscle changes and bone regeneration between reduction mandibuloplasty along with partial masseter muscle resection and reduction mandibuloplasty alone.

Methods: Forty-seven patients who complained of prominent mandibular angle and hypertrophy masseter muscles (MMH) were divided into group 1 treated with reduction mandibuloplasty along with partial masseter muscle resection, and group 2 treated with reduction mandibuloplasty alone. Pre-5 days and long-term postoperative computed tomography data were collected, and the masseter muscle volume, hemi-mandible volume, and unilateral lower face width were measured. Patient satisfaction and complication were also evaluated.

Results: At long-term follow-up, group 1 showed a greater decrease in masseter volume (p < 0.001), and lower face width (p < 0.001), and less bone regeneration (p < 0.001) than group 2. Furthermore, patients in group 1 had higher satisfaction with the surgical outcome (p < 0.05).

Conclusion: Reduction mandibuloplasty along with partial masseter muscle resection can achieve a slender frontal appearance and significantly decrease bone generation. For patients with MMH, reduction mandibuloplasty along with partial masseter muscle resection is an effective and predictable lower face reshaping surgery.

Level Of Evidence Iv: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .
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http://dx.doi.org/10.1007/s00266-021-02356-7DOI Listing
May 2021

Safety and efficacy of meplazumab in healthy volunteers and COVID-19 patients: a randomized phase 1 and an exploratory phase 2 trial.

Signal Transduct Target Ther 2021 05 17;6(1):194. Epub 2021 May 17.

Department of Clinical Immunology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.

Recent evidence suggests that CD147 serves as a novel receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Blocking CD147 via anti-CD147 antibody could suppress the in vitro SARS-CoV-2 replication. Meplazumab is a humanized anti-CD147 IgG monoclonal antibody, which may effectively prevent SARS-CoV-2 infection in coronavirus disease 2019 (COVID-19) patients. Here, we conducted a randomized, double-blinded, placebo-controlled phase 1 trial to evaluate the safety, tolerability, and pharmacokinetics of meplazumab in healthy subjects, and an open-labeled, concurrent controlled add-on exploratory phase 2 study to determine the efficacy in COVID-19 patients. In phase 1 study, 59 subjects were enrolled and assigned to eight cohorts, and no serious treatment-emergent adverse event (TEAE) or TEAE grade ≥3 was observed. The serum and peripheral blood C and area under the curve showed non-linear pharmacokinetic characteristics. No obvious relation between the incidence or titer of positive anti-drug antibody and dosage was observed in each cohort. The biodistribution study indicated that meplazumab reached lung tissue and maintained >14 days stable with the lung tissue/cardiac blood-pool ratio ranging from 0.41 to 0.32. In the exploratory phase 2 study, 17 COVID-19 patients were enrolled, and 11 hospitalized patients were involved as concurrent control. The meplazumab treatment significantly improved the discharged (P = 0.005) and case severity (P = 0.021), and reduced the time to virus negative (P = 0.045) in comparison to the control group. These results show a sound safety and tolerance of meplazumab in healthy volunteers and suggest that meplazumab could accelerate the recovery of patients from COVID-19 pneumonia with a favorable safety profile.
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http://dx.doi.org/10.1038/s41392-021-00603-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8127508PMC
May 2021

Predictive value of pentraxin-3 on disease severity and mortality risk in patients with hemorrhagic fever with renal syndrome.

BMC Infect Dis 2021 May 17;21(1):445. Epub 2021 May 17.

Center for Infectious Diseases, Second Affiliated Hospital of Air Force Medical University, 569 Xinsi Rd, Baqiao District, Xi'an, 710038, Shaanxi, China.

Background: Hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus is characterized by systemic immunopathological injury. Pentraxin-3 is an acute-phase reactant involved in the processes of inflammation and infection. This study aimed to investigate the levels of plasma pentraxin-3 and evaluate its predictive value on disease severity and mortality risk in patients with HFRS.

Methods: This was a prospective real-world observational study. The concentrations of plasma pentraxin-3 were measured by enzyme linked immunosorbent assay (ELISA) in 105 HFRS patients and 27 healthy controls. We analyzed the clinical relevance between pentraxin-3 and clinical subtyping, hospital stay and conventional laboratory parameters of HFRS patients. Considering the prognosis (death) as the primary endpoint, the levels of pentraxin-3 between survivors and non-survivors were compared, and its association with mortality was assessed by Kaplan-Meier survival analysis. The predictive potency of pentraxin-3 for mortality risk in HFRS patients was evaluated by receiver operating characteristic (ROC) curve analysis.

Results: The levels of pentraxin-3 during the acute phase were increased with the aggravation of the disease, and showed the highest expression in critical-type patients (P < 0.05). Pentraxin-3 demonstrated significant correlations with conventional laboratory parameters (WBC, PLT, AST, ALB, APTT, Fib) and the length of hospital stay. Compared with the survivors, non-survivors showed higher levels of pentraxin-3 and worse expressions of conventional laboratory parameters during the acute phase. The Kaplan-Meier survival curves showed that high levels of pentraxin-3 during the acute phase were significantly associated with the death in HFRS patients. Pentraxin-3 demonstrated significant predictive value for the mortality risk of HFRS patients, with the area under ROC curve (AUC) of 0.753 (95%CI: 0.593 ~ 0.914, P = 0.003).

Conclusions: The detection of plasma pentraxin-3 might be beneficial to the evaluation of disease severity and to the prediction of mortality risk in HFRS patients.
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http://dx.doi.org/10.1186/s12879-021-06145-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8130374PMC
May 2021

Identification of potential autophagy-associated lncRNA in prostate cancer.

Aging (Albany NY) 2021 05 10;13(9):13153-13165. Epub 2021 May 10.

Department of Urology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.

Background: Long non-coding RNAs (lncRNAs) have been linked to autophagy. It is urgent to identify and assess the hub autophagy-associated lncRNA in prostate cancer.

Methods: Differentially expressed lncRNAs associated with autophagy were identified in prostate cancer based on The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA-PRAD) data. An autophagy-mediated competing endogenous RNA network was constructed to screen for autophagy-associated lncRNA, and the preselected lncRNAs were further validated using Gene Expression Omnibus (GEO) datasets. Furthermore, a prognostic lncRNA signature was established and assessed. Additionally, Gene Set Enrichment Analysis (GSEA) revealed the underlying molecular mechanisms.

Results: Using a competing endogenous RNA network, 66 differentially expressed lncRNAs associated with autophagy were identified, and the differential expression of 7 lncRNAs were verified using the TCGA-PRAD, GSE21034, and GSE94767 datasets. Additionally, a lncRNA signature associated with autophagy, including MKNK1-AS1 and INE1, was identified as an independent indicator of survival with a C-index of 0.882. The GSEA analysis indicated that several autophagy-related signaling pathways were enriched in different risk groups.

Conclusions: The lncRNAs associated with autophagy were identified, and a prediction model was developed that could be used as a prognostic predictor for prostate cancer, indicating the critical role of lncRNA in the regulation of prostate cancer autophagy regulation.
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http://dx.doi.org/10.18632/aging.202997DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8148478PMC
May 2021

LncRNA TUG1 silencing enhances proliferation and migration of ox-LDL-treated human umbilical vein endothelial cells and promotes atherosclerotic vascular injury repairing via the Runx2/ANPEP axis.

Int J Cardiol 2021 May 8. Epub 2021 May 8.

Department of Cardiology, Second Hospital of Hebei Medical University, NO.215 Hepingxi Road, Xinhua District, Shijiazhuang, Hebei, China.

The role of vascular endothelial cell injury in the course of atherosclerosis (AS) has attracted increasing attention. Long non-coding RNAs (LncRNAs) are demonstrated to be the biomarker for the diagnosis of AS. This study investigated the mechanism of lncRNA taurine upregulated gene 1 (TUG1) in AS. Microarray data of AS obtained from GEO database showed that lncRNA TUG1 was differentially expressed in AS samples. TUG1 expression was upregulated in ox-LDL-treated human umbilical vein endothelial cells (HUVECs). Oxidized low density lipoprotein (ox-LDL)-treated HUVECs were then transfected with sh-TUG1. TUG1 silencing promoted proliferation and migration of ox-LDL-treated HUVECs. TUG1 bound to Runt-related transcription factor 2 (Runx2). Runx2 silencing promoted proliferation and migration of HUVECs. The downstream genes of Runx2 were predicted by hTFtarget database. The binding site of Runx2 and Aminopeptidase N (ANPEP) was determined. Runx2 silencing reversed the repression effect of overexpressing ANPEP on cell proliferation and migration. TUG1 silencing inhibited ANPEP expression via Runx2 to promote HUVEC proliferation and migration. A mouse model of AS was established. The area of atherosclerotic lesions of mouse aorta was detected, and vascular re-endothelialization was evaluated. TUG1 silencing promoted vascular injury repairing and inhibited AS in vivo. In conclusion, TUG1 silencing enhanced proliferation and migration of ox-LDL-treated HUVECs and promoted vascular injury repairing in vivo via the Runx2/ANPEP axis.
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http://dx.doi.org/10.1016/j.ijcard.2021.05.014DOI Listing
May 2021

Letter comments on: "A comparison of the efficacy of autologous fibrin glue/platelet-poor plasma versus suction drainage in preventing hematoma and seroma in rhytidectomy: A randomized, double-blind, controlled study".

J Plast Reconstr Aesthet Surg 2021 Apr 22. Epub 2021 Apr 22.

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100144, PR China. Electronic address:

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http://dx.doi.org/10.1016/j.bjps.2021.03.128DOI Listing
April 2021

A New Forceps for Suture Removal After Double Eyelid Blepharoplasty.

Aesthetic Plast Surg 2021 May 4. Epub 2021 May 4.

16th Department, Plastic Surgery Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, 33 Badachu Road, Shijingshan District, Beijing, China.

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http://dx.doi.org/10.1007/s00266-021-02328-xDOI Listing
May 2021

Apramycin resistance in epidemic carbapenem-resistant Klebsiella pneumoniae ST258 strains.

J Antimicrob Chemother 2021 May 3. Epub 2021 May 3.

Center for Discovery and Innovation, Hackensack-Meridian Health, Nutley, NJ, USA.

Background: Recent studies indicated that the monosubstituted deoxystreptamine aminoglycoside apramycin is a potent antibiotic against a wide range of MDR Gram-negative pathogens.

Objectives: To evaluate the in vitro activity of apramycin against carbapenem-resistant Klebsiella pneumoniae (CRKp) isolates from New York and New Jersey, and to explore mechanisms of apramycin resistance.

Methods: Apramycin MICs were determined by broth microdilution for 155 CRKp bloodstream isolates collected from 2013 to 2018. MLST STs, wzi capsular types and apramycin resistance gene aac(3')-IV were examined by PCR and Sanger sequencing. Selected isolates were further characterized by conjugation experiments and WGS.

Results: Apramycin MIC50/90 values were 8 and >128 mg/L for CRKp isolates, which are much higher than previously reported. Twenty-four isolates (15.5%) were apramycin resistant (MIC ≥64 mg/L) and they were all from the K. pneumoniae ST258 background. The 24 apramycin-resistant K. pneumoniae ST258 strains belonged to six different capsular types and 91.7% of them harboured the apramycin resistance gene aac(3')-IV. Sequencing analysis showed that different ST258 capsular type strains shared a common non-conjugative IncR plasmid, co-harbouring aac(3')-IV and blaKPC. A novel IncR and IncX3 cointegrate plasmid, p59494-RX116.1, was also identified in an ST258 strain, demonstrating how apramycin resistance can be spread from a non-conjugative plasmid through cointegration.

Conclusions: We described a high apramycin resistance rate in clinical CRKp isolates in the New York/New Jersey region, mainly among the epidemic K. pneumoniae ST258 strains. The high resistance rate in an epidemic K. pneumoniae clone raises concern regarding the further optimization and development of apramycin and apramycin-like antibiotics.
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http://dx.doi.org/10.1093/jac/dkab131DOI Listing
May 2021

Virulence Factors in Hypervirulent .

Front Microbiol 2021 8;12:642484. Epub 2021 Apr 8.

Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, China.

Hypervirulent (hvKP) has spread globally since first described in the Asian Pacific Rim. It is an invasive variant that differs from the classical (cKP), with hypermucoviscosity and hypervirulence, causing community-acquired infections, including pyogenic liver abscess, pneumonia, meningitis, and endophthalmitis. It utilizes a battery of virulence factors for survival and pathogenesis, such as capsule, siderophores, lipopolysaccharide, fimbriae, outer membrane proteins, and type 6 secretion system, of which the former two are dominant. This review summarizes these hvKP-associated virulence factors in order to understand its molecular pathogenesis and shed light on new strategies to improve the prevention, diagnosis, and treatment of hvKP-causing infection.
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http://dx.doi.org/10.3389/fmicb.2021.642484DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8060575PMC
April 2021

Environmental factors shape the epiphytic bacterial communities of Gracilariopsis lemaneiformis.

Sci Rep 2021 Apr 21;11(1):8671. Epub 2021 Apr 21.

Institute of Marine Sciences, Guangdong Provincial Key Laboratory of Marine Biotechnology and STU-UNIVPM Joint Algal Research Center, College of Science, Shantou University, Shantou, China.

Macroalgae host various symbionts on their surface, which play a critical role in their growth and development processes. However, there is still incomplete understanding of this epiphytic bacteria-host algae interactions. This study comprehensively analysed variation of the epiphytic bacterial communities (EBC) composition of red macroalga Gracilariopsis lemaneiformis at different geographic locations and environmental factors (i.e., nitrogen and phosphorus), which shape the EBC composition of G. lemaneiformis. The composition and structure of EBC were characterized using high throughput sequencing of the V3-V4 hypervariable region of the 16S rRNA gene. The results revealed that epiphytic bacteria varied significantly among three different geographic locations in China, i.e., Nan'ao Island (NA), Lianjiang County (LJ), and Nanri Island (NR). Redundancy analysis (RDA) showed that the relative abundance of Bacteroidetes, Firmicutes, Verrucomicrobia, and Epsilonbacteraeota at NR were strongly positively correlated with total nitrogen (TN), total phosphorus (TP), nitrate nitrogen (NO-N), and dissolved inorganic nitrogen (DIN), but negatively correlated with nitrite nitrogen (NO-N). The relative abundance of Cyanobacteria at NA and LJ were strongly positively correlated with NO-N, but negatively correlated with TN, TP, NO-N, and DIN. Besides, the Mantel test results indicated that the EBC composition was significantly correlated with these environmental factors, which was also confirmed by Spearman correlation analysis. Thus, environmental factors such as NO-N and DIN play a key role in the community composition of epiphytic bacteria on G. lemaneiformis. This study provides important baseline knowledge on the community composition of epiphytic bacteria on G. lemaneiformis and shows correlation between different epiphytic bacteria and their surrounding environmental factors.
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http://dx.doi.org/10.1038/s41598-021-87977-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8060329PMC
April 2021

BATF Regulates T Regulatory Cell Functional Specification and Fitness of Triglyceride Metabolism in Restraining Allergic Responses.

J Immunol 2021 May 19;206(9):2088-2100. Epub 2021 Apr 19.

Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN;

Preserving appropriate function and metabolism in regulatory T (Treg) cells is crucial for controlling immune tolerance and inflammatory responses. Yet how Treg cells coordinate cellular metabolic programs to support their functional specification remains elusive. In this study, we report that BATF couples the T2-suppressive function and triglyceride (TG) metabolism in Treg cells for controlling allergic airway inflammation and IgE responses. Mice with Treg-specific ablation of BATF developed an inflammatory disorder characterized by T2-type dominant responses and were predisposed to house dust mite-induced airway inflammation. Loss of BATF enabled Treg cells to acquire T2 cell-like characteristics. Moreover, BATF-deficient Treg cells displayed elevated levels of cellular TGs, and repressing or elevating TGs, respectively, restored or exacerbated their defects. Mechanistically, TCR/CD28 costimulation enhanced expression and function of BATF, which sustained IRF4 activity to preserve Treg cell functionality. Thus, our studies reveal that BATF links Treg cell functional specification and fitness of cellular TGs to control allergic responses, and suggest that therapeutic targeting of TG metabolism could be used for the treatment of allergic disease.
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http://dx.doi.org/10.4049/jimmunol.2001184DOI Listing
May 2021

Changes of Mineralogical Properties and Biological Activities of Gypsum and Its Calcined Products with Different Phase Structures.

Evid Based Complement Alternat Med 2021 9;2021:6676797. Epub 2021 Mar 9.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China.

Raw gypsum (RG) and calcined gypsum (CG) are widely used in traditional Chinese medicine (TCM). RG is usually taken orally to resolve heat and diminish inflammation, while CG is only used externally to treat ulcerations and empyrosis. Calcination at different temperatures, three phase CG structures, namely, bassanite, anhydrite III, and anhydrite II, may be generated. We herein investigated the relationship between the phase structure and the efficacy of CG and the optimum phase structure for CG. RG has a compact structure, small pore size, weak anti-inflammatory effect, but no antibacterial effect, and has almost no effect on the repair of scalds. CG150 (bassanite) has a loose texture, large pore size and specific surface area, and certain antibacterial and anti-inflammatory effects, but it has a poor repair effect on scalds. CG750 (anhydrite II) has a compact structure, small pore size and specific surface area, and low antibacterial and anti-inflammatory effects, but it has a certain repair effect on scalds. Only CG350 (anhydrite III) has good performance in texture, pore size, specific surface area, antibacterial, anti-inflammatory, and scald repair. Our research has proved that the mineral properties and biological activities of CG are different due to different phase structures. CG350, namely, anhydrite III, is considered by our research to be the optimal phase structure as CG.
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http://dx.doi.org/10.1155/2021/6676797DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969087PMC
March 2021

Attenuated TGFB signalling in macrophages decreases susceptibility to DMBA-induced mammary cancer in mice.

Breast Cancer Res 2021 Mar 24;23(1):39. Epub 2021 Mar 24.

Discipline of Surgery, Adelaide Medical School, The Queen Elizabeth Hospital, University of Adelaide, Adelaide, Australia.

Background: Transforming growth factor beta1 (TGFB1) is a multi-functional cytokine that regulates mammary gland development and cancer progression through endocrine, paracrine and autocrine mechanisms. TGFB1 also plays roles in tumour development and progression, and its increased expression is associated with an increased breast cancer risk. Macrophages are key target cells for TGFB1 action, also playing crucial roles in tumourigenesis. However, the precise role of TGFB-regulated macrophages in the mammary gland is unclear. This study investigated the effect of attenuated TGFB signalling in macrophages on mammary gland development and mammary cancer susceptibility in mice.

Methods: A transgenic mouse model was generated, wherein a dominant negative TGFB receptor is activated in macrophages, in turn attenuating the TGFB signalling pathway specifically in the macrophage population. The mammary glands were assessed for morphological changes through wholemount and H&E analysis, and the abundance and phenotype of macrophages were analysed through immunohistochemistry. Another cohort of mice received carcinogen 7,12-dimethylbenz(a)anthracene (DMBA), and tumour development was monitored weekly. Human non-neoplastic breast tissue was also immunohistochemically assessed for latent TGFB1 and macrophage marker CD68.

Results: Attenuation of TGFB signalling resulted in an increase in the percentage of alveolar epithelium in the mammary gland at dioestrus and an increase in macrophage abundance. The phenotype of macrophages was also altered, with inflammatory macrophage markers iNOS and CCR7 increased by 110% and 40%, respectively. A significant decrease in DMBA-induced mammary tumour incidence and prolonged tumour-free survival in mice with attenuated TGFB signalling were observed. In human non-neoplastic breast tissue, there was a significant inverse relationship between latent TGFB1 protein and CD68-positive macrophages.

Conclusions: TGFB acts on macrophage populations in the mammary gland to reduce their abundance and dampen the inflammatory phenotype. TGFB signalling in macrophages increases mammary cancer susceptibility potentially through suppression of immune surveillance activities of macrophages.
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http://dx.doi.org/10.1186/s13058-021-01417-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992865PMC
March 2021

A Modified Procedure for Single-eyelid Asian Females with Lacrimal Gland Prolapse: Lacrimal Gland Reposition combined with Fat Transposition in Double-eyelid Operation.

Aesthetic Plast Surg 2021 Mar 15. Epub 2021 Mar 15.

16th department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, #33 Badachu Road, Shijingshan District, 100144, Beijing, China.

Background: The awareness and treatment of lacrimal gland prolapse (LGP) have been primarily improved with a further understanding of lateral eyelid bulging over the decades. However, for Asian single-eyelid females with LGP, a tailor-made procedure applicable to their comparatively young puffy eyes is needed.

Methods: This is a retrospective study. From Jan. 2009 to Jan. 2019, two hundred and three Asian single-eyelid females with LGP, who met the inclusion criteria, underwent double-eyelid surgeries and adjunctive lacrimal gland repositions with preaponeurotic fat transposition. Pertinent demographics, complications, pre-and post-operative photography were collected.

Results: A total of 167 patients completed the 4-24 months' follow-up (average: 16.3 months). One hundred and thirty-two cases (79.0%) were diagnosed as LGP preoperatively, and the rest (35/167, 21.0%) were diagnosed intraoperatively. All patients (average: 28.4 years old) received modified blepharoplasty. Postoperative symptoms involving local mild pain (2.9%, 5/167), upper eyelid tightness (3.6%, 6/167), and moderate epiphora (9.0%, 15/167) were all recovered spontaneously within one month. Prolapse recurrence and severe complications such as dry eye syndrome were not observed.

Conclusions: We proposed a modified procedure to enhance the diagnosis and treatment of LGP during Asian blepharoplasty. The lacrimal gland suspension and fat transposition assured the cosmetic outcome for selected young, puffy Asian eyes. The supratarsal creases were satisfactory, and the complication rate was low. Furthermore, the rearrangement of preaponeurotic fat smoothed the contour transition and preserved the orbital volume. Therefore, this is a safe and effective technique worth recommending.
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http://dx.doi.org/10.1007/s00266-021-02213-7DOI Listing
March 2021

High Definition Lipoabdominoplasty.

Aesthetic Plast Surg 2021 Feb 25. Epub 2021 Feb 25.

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Shijingshan District, 33 Badachu Road, Beijing, 100144, China.

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http://dx.doi.org/10.1007/s00266-021-02153-2DOI Listing
February 2021

Insulin gene enhancer protein 1 mediates glycolysis and tumorigenesis of gastric cancer through regulating glucose transporter 4.

Cancer Commun (Lond) 2021 Mar 11;41(3):258-272. Epub 2021 Feb 11.

Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Division of Gastrointestinal Cancer Translational Research Laboratory, Peking University Cancer Hospital & Institute, Beijing, 100142, P. R. China.

Background: Insulin gene enhancer protein 1, (ISL1), a LIM-homeodomain transcription factor, is involved in multiple tumors and is associated with insulin secretion and metabolic phenotypes. However, the role of ISL1 in stimulating glycolysis to promote tumorigenesis in gastric cancer (GC) is unclear. In this study, we aimed to characterize the expression pattern of ISL1 in GC patients and explore its molecular biological mechanism in glycolysis and tumorigenesis.

Methods: We analyzed the expression and clinical significance of ISL1 in GC using immunohistochemistry and real-time polymerase chain reaction (PCR). Flow cytometry and IncuCyte assays were used to measure cell proliferation after ISL1 knockdown. RNA-sequencing was performed to identify differentially expressed genes, followed by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene Set Enrichment Analysis (GSEA) to reveal key signaling pathways likely regulated by ISL1 in GC. Alteration of the glycolytic ability of GC cells with ISL1 knockdown was validated by measuring the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) and by detecting glucose consumption and lactate production. The expression of glucose transporter 4 (GLUT4) and ISL1 was assessed by Western blotting, immunohistochemistry, and immunofluorescent microscopy. The luciferase reporter activity and chromatin immunoprecipitation assays were performed to determine the transcriptional regulation of ISL1 on GLUT4.

Results: High levels of ISL1 and GLUT4 expression was associated with short survival of GC patients. ISL1 knockdown inhibited cell proliferation both in vitro and in vivo. KEGG analysis and GSEA for RNA-sequencing data indicated impairment of the glycolysis pathway in GC cells with ISL1 knockdown, which was validated by reduced glucose uptake and lactate production, decreased ECAR, and increased OCR. Mechanistic investigation indicated that ISL1 transcriptionally regulated GLUT4 through binding to its promoter.

Conclusion: ISL1 facilitates glycolysis and tumorigenesis in GC via the transcriptional regulation of GLUT4.
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http://dx.doi.org/10.1002/cac2.12141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7968886PMC
March 2021

Endoplasmic Reticulum-Mediated Protein Quality Control and Endoplasmic Reticulum-Associated Degradation Pathway Explain the Reduction of N-glycoprotein Level Under the Lead Stress.

Front Plant Sci 2020 13;11:598552. Epub 2021 Jan 13.

Guangdong Provincial Key Laboratory of Marine Biotechnology, STU-UNIVPM Joint Algal Research Center, College of Sciences, Institute of Marine Sciences, Shantou University, Shantou, China.

Different anthropogenic activities result in the continuous increase of metal lead (Pb) in the environment and adversely affect living organisms. Therefore, it is important to investigate the tolerance mechanism in a model organism. is an important green eukaryotic model microalga for studying different kinds of biological questions. In this study, the responses of were revealed via a comprehensive approach, including physiological, genomic, transcriptomic, glycomic, and bioinformatic techniques. Physiological results showed that the growth rate and soluble protein content were significantly reduced under the high lead stress. Also, the results obtained from the genomic and transcriptomic analyses presented that the endoplasmic reticulum-mediated protein quality control (ERQC) system and endoplasmic reticulum-associated degradation (ERAD) pathway were activated under the third day of high lead stress. The unique upregulated protein disulfide isomerase genes on the ERQC system were proposed to be important for the protein level and protein quality control. The accumulation of specific N-glycans indicated that specific N-glycosylation of proteins might alter the biological functions of proteins to alleviate the Pb stress in alga and/or lead to the degradation of incomplete/misfolded proteins. At the same time, it was observed that genes involved in each process of ERAD were upregulated, suggesting that the ERAD pathway was activated to assist the degradation of incomplete/misfolded proteins. Therefore, it is reasonable to speculate that the reduction of protein level under the high lead stress was related to the activated ERQC system and QRAD pathway. Our findings will provide a solid and reliable foundation and a proposed ERAD working model for further in-depth study of the ERQC system and ERAD pathway under the Pb stress and even other biotic and abiotic stresses.
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http://dx.doi.org/10.3389/fpls.2020.598552DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7838096PMC
January 2021

[Influence of different sintering temperatures on mesoporous structure and ectopic osteogenesis of biphasic calcium phosphate ceramic granule materials].

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi 2021 Jan;35(1):95-103

The 16th Department of Plastic Surgery, Plastic Surgery Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100144, P.R.China.

Objective: To detect the difference in the osteogenesis ability of biphasic calcium phosphate (BCP) ceramic granular materials with different mesoporous diameters prepared at different sintering temperatures through and experiments, so as to provide evidence for screening BCP materials with better clinical application parameters.

Methods: Three kinds of BCP (materials 1, 2, 3) were prepared by mixing hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) at a ratio of 8∶2 and sintered at 1 050, 1 150, and 1 250℃ for 3 hours, respectively. The internal porosity and the diameter, volume, and area of the mesopore were measured by Brunauer-Emmett-Teller test (BET); the composition of the material was evaluated by X-ray diffraction (XRD); the microscopic surface morphology of the material was observed by scanning electron microscopy (SEM). The 3rd generation bone marrow mesenchymal stem cells (BMSCs) from Sprague-Dawley rats were co-cultured with the materials 1, 2, and 3 for 7 days respectively (groups A, B, and C), and the cells adhesion on the materials was observed by SEM and phalloidine staining, respectively. Cell proliferation activity was measured by cell counting kit 8 method. , 9 muscle bags were made in dorsal muscles of 9 beagles, respectively. The muscle bags were randomly divided into 3 groups (3 per beagle in each group) and materials 1, 2, and 3 were placed into the muscle bags of groups A, B, and C, respectively. After 1, 2, and 3 months of operation, 3 beagles were anesthetized and the samples were stained with HE, Masson, and Safranin, and the bone formation area ratio in the BCP gap was calculated. Real-time fluorescence quantitative PCR (qRT-PCR) was performed to detect the expressions of bone-related genes [including alkaline phosphatase (ALP), osteopontin (OPN), and osteocalcin (OC)].

Results: The BET test showed that with the increase of sintering temperature, the internal porosity of the particles did not change significantly, but the diameter, volume, and area of the mesopores gradually decreased. The XRD detection showed that the XRD waves of HA and β-TCP could be seen in all 3 kinds of materials; SEM showed that there were widely distributed macropores on the surface of 3 kinds of BCPs, and the interpores connected with the others. , BMSCs adhered and proliferated on the surfaces of 3 kinds of BCPs, and the cell biocompatibility of the materials in groups B and C was better than that in group A. , obvious osteoid tissue deposition could be observed in the intergranular space of 3 kinds of BCPs from 2 months after implantation. The bone formation area ratio of each group increased with time. The bone formation area ratio in group A was significantly higher than that in groups B and C at 2 and 3 months after implantation, and in group A than in group B at 1 month ( <0.05). qRT-PCR showed that the expressions of osteogenic related genes peaked at 2 months in group A, and gradually increased with time in groups B and C. The relative expressions of ALP and OPN mRNAs in group A were significantly higher than those in groups B and C at 1 month after implantation, the relative expression of OC mRNA in group A was significantly higher than that in groups B and C at 2 months after operation, the relative expression of ALP mRNA in groups B and C and the relative expression of OPN mRNA in group B were significantly higher than those in group A, all showing significant differences ( <0.05); there was no significant difference in the relative expression of each gene among the other groups at each time point ( >0.05).

Conclusion: The mesoporous diameter of BCP decreases with the increase of sintering temperature. Different mesoporous diameters lead to different ectopic osteogenesis of BCP materials. BCP material with mesoporous diameter of 12.57 nm has better osteogenic ability which can activate the osteogenic gene earlier. The mesoporous diameter is expected to be an adjustable index for optimizing the osteogenic capacity of BCP materials.
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http://dx.doi.org/10.7507/1002-1892.202007074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8171604PMC
January 2021

Letter to the editor.

Int J Pediatr Otorhinolaryngol 2021 02 1;141:110603. Epub 2021 Jan 1.

The Sixteenth Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Shijingshan District, Beijing, PR China.

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http://dx.doi.org/10.1016/j.ijporl.2020.110603DOI Listing
February 2021

Phylotranscriptomics reveals the complex evolutionary and biogeographic history of the genus Tsuga with an East Asian-North American disjunct distribution.

Mol Phylogenet Evol 2021 04 31;157:107066. Epub 2020 Dec 31.

State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:

The disjunct distribution between East Asia and North America is one of the best established biogeographic patterns. A robust phylogeny is fundamental for understanding the biogeographic histories of taxa with this distribution pattern. Tsuga (hemlock) is a genus of Pinaceae with a typical intercontinental disjunct distribution in East Asia and eastern and western North America, and its phylogeny has not been completely reconstructed in previous studies. In this study, we reconstructed a highly resolved phylogeny of Tsuga using 881 nuclear genes, 60 chloroplast genes and 23 mitochondrial genes and explored its biogeographic and reticulate evolutionary history. The results of phylogenetic analysis, molecular dating and ancestral area reconstruction indicate that Tsuga very likely originated from North America in the late Oligocene and dispersed from America to East Asia via the Bering Land Bridge during the middle Miocene. In particular, we found complex reticulate evolutionary pattern among the East Asian hemlock species. T. sieboldii possibly originated from hybridization with the ancestor of T. chinensis from mainland China and T. forrestii as the paternal donor and the ancestor of T. diversifolia and T. ulleungensis as the maternal donor. T. chinensis (Taiwan) could have originated by hybridization together with T. sieboldii and then evolved independently after dispersal to the Taiwan Island, subsequently experiencing mitochondrial DNA introgression with T. chinensis from mainland China. Moreover, our study found that T. chinensis from western China is more closely related to T. forrestii than to T. chinensis from eastern China. The nonmonophyletic T. chinensis needs taxonomic reconsideration.
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http://dx.doi.org/10.1016/j.ympev.2020.107066DOI Listing
April 2021

Polymyxin resistance in carbapenem-resistant Enterobacteriaceae isolates from patients without polymyxin exposure: a multicentre study in China.

Int J Antimicrob Agents 2021 Feb 23;57(2):106262. Epub 2020 Dec 23.

(a)Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, PR China. Electronic address:

Polymyxins were recently approved for the clinical treatment of carbapenem-resistant Enterobacteriaceae (CRE) infections in China. The aim of this study was to determine the prevalence and molecular mechanisms of polymyxin-resistant CRE prior to the clinical application of polymyxin and to evaluate the potential for emerging polymyxin resistance in China. A total of 504 unique CRE isolates were collected from six tertiary-care hospitals in China between October 2016 and September 2017. All isolates underwent antimicrobial susceptibility testing. Clinical, demographic, antimicrobial exposure and infection data were collected from patients' medical charts. PCR detection, Sanger sequencing and reverse transcription real-time fluorescence quantitative PCR (RT-qPCR) were used to investigate the molecular mechanism of polymyxin resistance. A total 19 (3.8%) polymyxin-resistant isolates were identified, including Klebsiella pneumoniae, Escherichia coli, Klebsiella aerogenes and Enterobacter cloacae. Genetic analysis in K. pneumoniae strains identified insertion sequence (IS) elements (n = 3), a stop codon (n = 1) and gene deletion (n = 2) in mgrB and a pmrB missense mutation (T157P) (n = 1). Two E. coli isolates contained mcr-1 and an E. cloacae strain harboured a frameshift in mgrB. Further transcriptional analysis showed that pmrA, pmrB, pmrC and pmrK were significantly upregulated in polymyxin-resistant isolates. Despite the lack of polymyxin exposure, 3.8% of CRE were resistant to polymyxin in China. Both chromosomal and plasmid-encoded mechanisms were identified. Our study suggests that clinical practice should be alert to pre-existing polymyxin resistance among CRE isolates to avoid further dissemination of polymyxin resistance.
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http://dx.doi.org/10.1016/j.ijantimicag.2020.106262DOI Listing
February 2021

Prevention of Umbilical Sagging After Medium Definition Liposuction.

Aesthet Surg J 2021 03;41(4):NP142-NP145

16th Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.

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http://dx.doi.org/10.1093/asj/sjaa279DOI Listing
March 2021

Scattered Multilayered Retinal Hemorrhage Secondary to Anterior Chamber Paracentesis, Mimicking a Hematological Disorder.

JAMA Ophthalmol 2020 12 10;138(12):e202389. Epub 2020 Dec 10.

Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.

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http://dx.doi.org/10.1001/jamaophthalmol.2020.2389DOI Listing
December 2020

Genetic diversity and characteristics of high-level tigecycline resistance Tet(X) in Acinetobacter species.

Genome Med 2020 12 7;12(1):111. Epub 2020 Dec 7.

National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.

Background: The recent emergence and dissemination of high-level mobile tigecycline resistance Tet(X) challenge the clinical effectiveness of tigecycline, one of the last-resort therapeutic options for complicated infections caused by multidrug-resistant Gram-negative and Gram-positive pathogens. Although tet(X) has been found in various bacterial species, less is known about phylogeographic distribution and phenotypic variance of different genetic variants.

Methods: Herein, we conducted a multiregional whole-genome sequencing study of tet(X)-positive Acinetobacter isolates from human, animal, and their surrounding environmental sources in China. The molecular and enzymatic features of tet(X) variants were characterized by clonal expression, microbial degradation, reverse transcription, and gene transfer experiments, while the tet(X) genetic diversity and molecular evolution were explored by comparative genomic and Bayesian evolutionary analyses.

Results: We identified 193 tet(X)-positive isolates from 3846 samples, with the prevalence ranging from 2.3 to 25.3% in nine provinces in China. The tet(X) was broadly distributed in 12 Acinetobacter species, including six novel species firstly described here. Besides tet(X3) (n = 188) and tet(X4) (n = 5), two tet(X5) variants, tet(X5.2) (n = 36) and tet(X5.3) (n = 4), were also found together with tet(X3) or tet(X4) but without additive effects on tetracyclines. These tet(X)-positive Acinetobacter spp. isolates exhibited 100% resistance rates to tigecycline and tetracycline, as well as high minimum inhibitory concentrations to eravacycline (2-8 μg/mL) and omadacycline (8-16 μg/mL). Genetic analysis revealed that different tet(X) variants shared an analogous ISCR2-mediated transposon structure. The molecular evolutionary analysis indicated that Tet(X) variants likely shared the same common ancestor with the chromosomal monooxygenases that are found in environmental Flavobacteriaceae bacteria, but sequence divergence suggested separation ~ 9900 years ago (7887 BC), presumably associated with the mobilization of tet(X)-like genes through horizontal transfer.

Conclusions: Four tet(X) variants were identified in this study, and they were widely distributed in multiple Acinetobacter spp. strains from various ecological niches across China. Our research also highlighted the crucial role of ISCR2 in mobilizing tet(X)-like genes between different Acinetobacter species and explored the evolutionary history of Tet(X)-like monooxygenases. Further studies are needed to evaluate the clinical impact of these mobile tigecycline resistance genes.
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http://dx.doi.org/10.1186/s13073-020-00807-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7722449PMC
December 2020