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1.
Adv Mater ; : e2407138, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38887139

ABSTRACT

MXene aerogels, known for good electrical properties, offer immense potential for the development of high-sensitivity pressure sensors. However, the intrinsic challenges stemming from the poor self-assembly capability and high hydrophilicity of MXene impedes the natural drying process of MXene-based hydrogels, thereby constraining their application on a large-sacle in sensor technology. Herein, we propose a graphene-assisted approach aimed at modulating the hydrophobicity and enhancing framework strength of MXene through a well-designed prefreezing technique incorporating three-dimensional (3D) spherical macro-porous structures. This synergistic strategy enables the fabrication of naturally dried MXene aerogels across various size scales. Moreover, the integration of 3D spherical macro-porous structures improves elasticity and electrical responsiveness of aerogels. Consequently, the aerogel sensor exhibits great performances, including high sensitivity (1250 KPa-1), low detection limit (0.4 Pa), wide frequency response range (0.1-8 Hz), and excellent stability (1000 cycles). This sensor proves adept at monitoring pressure signals ranging from lightweight paper to human motion. Additionally, the application of customized laser engraving endows aerogels with unique functionalities, such as compressibility and immunity to strain, stretchability and resistance to compression, as well as wind detection. Thus, our proposed approach holds significant promise as a scalable method for the mass production of aerogels with versatile applications. This article is protected by copyright. All rights reserved.

2.
PLoS One ; 19(5): e0300586, 2024.
Article in English | MEDLINE | ID: mdl-38748718

ABSTRACT

In civil engineering, stability analysis of slope is one of the main content of design. By using the finite element limit analysis software OptumG2, a landslide geological model is established to simulate the failure process of the landslide in Huadu District, Guangzhou City, China. The analysis focused on the deformation and failure characteristics, as well as the mechanical mechanism of landslide; the landslide mode of homogeneous soil is circular sliding. Additionally, investigating the influencing factors affecting slope stability is crucial in engineering implementation; in which the five influencing factors are considered as follow: slope height, slope gradient, soil cohesion, soil internal friction angle, and soil unit weight, respectively. A stability calculation model for a soil slope is established under 25 working conditions based on strength reduction method and orthogonal experimental design, in which the relationship between the safety factor and slope height, slope gradient, soil cohesion, soil internal friction angle, and soil unit weight is obtained. As the slope height increases from 5m to 45m, the safety factor of soil slope gradually decreases from 2.21 to 0.94; As the slope gradient increases from 20° to 60°, the safety factor of soil slope decreases approximately linearly from 1.80 to 0.95; As the cohesion of soil increases from 10kpa to 30kpa, the safety factor of soil slope increases approximately linearly from 1.04 to 1.60; As the internal friction angle of soil increases from 10° to 30°, the safety factor of soil slope increases approximately linearly from 1.00 to 1.81; As the unit weight of soil increases from 13kN/m3 to 21kN/m3, the safety factor of soil slope decreases approximately linearly from 1.50 to 1.21. The influencing factors affecting the safety factor of soil slope in descending order are slope height, slope angle, soil internal friction angle, soil cohesion, and soil unit weight. The research has reference significance for studying the stability and failure laws of soil slopes and conducting landslide control on soil slopes.


Subject(s)
Landslides , Soil , Soil/chemistry , China , Models, Theoretical , Research Design
3.
PLoS One ; 19(2): e0298337, 2024.
Article in English | MEDLINE | ID: mdl-38330083

ABSTRACT

This paper investigates the sliding surface failure characteristics, earth pressure distribution law and stability safety factor of inverted T-type retaining wall by using the finite element limit analysis software OptumG2, the effects of width of wall heel plate, width of wall toe plate, thickness of bottom plate, soil-wall interface friction angle, soil cohesion and soil internal friction angle of filling on the failure characteristics of sliding surface, the earth pressure distribution law and stability safety factor of retaining walls are analyzed, The stability safety factor of the retaining wall showed a gradually increasing trend as the width of wall heel plate and wall toe plate increased; as the bottom plate thickness increases, the stability safety factor of the retaining wall gradually increases; as the soil-wall interface element reduction coefficient rises, that is, the internal friction angle of the soil-wall gradually increases to the soil internal friction angle, the stability safety factor of the retaining wall gradually increases; as the soil cohesion and internal friction angle increase, the stability safety factor of the retaining wall progressively increases. The safety factor of retaining wall increases by 0.45 for every 0.5m increase in the width of the wall heel plate; the safety factor of the retaining wall increases by 0.29 when the width of the wall toe plate increases by 0.5m; for every 0.5m increase in the width of wall plate thickness, the safety factor of the retaining wall is increased by 0.62; for every 0.25 increase in soil-wall interface element reduction coefficient, the safety factor of the retaining wall increases by 0.29; for every increase of 5KPa in soil cohesion, the safety factor of the retaining wall increased by 1.16; for every 5° increases in soil internal friction angle, the safety factor of retaining wall increases by 0.6. The research is significant for studying the failure laws and stability of retaining walls and providing references for retaining wall design.


Subject(s)
Bone Plates , Soil , Finite Element Analysis , Friction
4.
PNAS Nexus ; 3(2): pgae053, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38380057

ABSTRACT

The effective utilization of cellulose and hemicellulose, the main components of plant biomass, is a key technical obstacle that needs to be overcome for the economic viability of lignocellulosic biorefineries. Here, we firstly demonstrated that the thermophilic cellulolytic fungus Myceliophthora thermophila can simultaneously utilize cellulose and hemicellulose, as evidenced by the independent uptake and intracellular metabolism of cellodextrin and xylodextrin. When plant biomass serviced as carbon source, we detected the cellodextrin and xylodextrin both in cells and in the culture medium, as well as high enzyme activities related to extracellular oligosaccharide formation and intracellular oligosaccharide hydrolysis. Sugar consumption assay revealed that in contrast to inhibitory effect of glucose on xylose and cellodextrin/xylodextrin consumption in mixed-carbon media, cellodextrin and xylodextrin were synchronously utilized in this fungus. Transcriptomic analysis also indicated simultaneous induction of the genes involved in cellodextrin and xylodextrin metabolic pathway, suggesting carbon catabolite repression (CCR) is triggered by extracellular glucose and can be eliminated by the intracellular hydrolysis and metabolism of oligosaccharides. The xylodextrin transporter MtCDT-2 was observed to preferentially transport xylobiose and tolerate high cellobiose concentrations, which helps to bypass the inhibition of xylobiose uptake. Furthermore, the expression of cellulase and hemicellulase genes was independently induced by their corresponding inducers, which enabled this strain to synchronously utilize cellulose and hemicellulose. Taken together, the data presented herein will further elucidate the degradation of plant biomass by fungi, with implications for the development of consolidated bioprocessing-based lignocellulosic biorefinery.

5.
BMC Biotechnol ; 23(1): 50, 2023 11 29.
Article in English | MEDLINE | ID: mdl-38031036

ABSTRACT

BACKGROUND: Filamentous fungi are efficient degraders of plant biomass and the primary producers of commercial cellulolytic enzymes. While the transcriptional regulation mechanisms of cellulases have been continuously explored in lignocellulolytic fungi, the induction of cellulase production remains a complex multifactorial system, with several aspects still largely elusive. RESULTS: In this study, we identified a Zn2Cys6 transcription factor, designated as Clr-5, which regulates the expression of cellulase genes by influencing amino acid metabolism in Neurospora crassa during growth on cellulose. The deletion of clr-5 caused a significant decrease in secreted protein and cellulolytic enzyme activity of N. crassa, which was partially alleviated by supplementing with yeast extract. Transcriptomic profiling revealed downregulation of not only the genes encoding main cellulases but also those related to nitrogen metabolism after disruption of Clr-5 under Avicel condition. Clr-5 played a crucial role in the utilization of multiple amino acids, especially leucine and histidine. When using leucine or histidine as the sole nitrogen source, the Δclr-5 mutant showed significant growth defects on both glucose and Avicel media. Comparative transcriptomic analysis revealed that the transcript levels of most genes encoding carbohydrate-active enzymes and those involved in the catabolism and uptake of histidine, branched-chain amino acids, and aromatic amino acids, were remarkably reduced in strain Δclr-5, compared with the wild-type N. crassa when grown in Avicel medium with leucine or histidine as the sole nitrogen source. These findings underscore the important role of amino acid metabolism in the regulation of cellulase production in N. crassa. Furthermore, the function of Clr-5 in regulating cellulose degradation is conserved among ascomycete fungi. CONCLUSIONS: These findings regarding the novel transcription factor Clr-5 enhance our comprehension of the regulatory connections between amino acid metabolism and cellulase production, offering fresh prospects for the development of fungal cell factories dedicated to cellulolytic enzyme production in bio-refineries.


Subject(s)
Cellulase , Cellulases , Neurospora crassa , Cellulase/metabolism , Neurospora crassa/genetics , Neurospora crassa/metabolism , Histidine/genetics , Histidine/metabolism , Leucine/genetics , Leucine/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Cellulose/metabolism , Cellulases/genetics , Nitrogen/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal
6.
Nat Microbiol ; 8(10): 1880-1895, 2023 10.
Article in English | MEDLINE | ID: mdl-37640963

ABSTRACT

Cell-intrinsic defences constitute the first line of defence against intracellular pathogens. The guanosine triphosphatase RAB32 orchestrates one such defence response against the bacterial pathogen Salmonella, through delivery of antimicrobial itaconate. Here we show that the Parkinson's disease-associated leucine-rich repeat kinase 2 (LRRK2) orchestrates this defence response by scaffolding a complex between RAB32 and aconitate decarboxylase 1, which synthesizes itaconate from mitochondrial precursors. Itaconate delivery to Salmonella-containing vacuoles was impaired and Salmonella replication increased in LRRK2-deficient cells. Loss of LRRK2 also restored virulence of a Salmonella mutant defective in neutralizing this RAB32-dependent host defence pathway in mice. Cryo-electron tomography revealed tether formation between Salmonella-containing vacuoles and host mitochondria upon Salmonella infection, which was significantly impaired in LRRK2-deficient cells. This positions LRRK2 centrally within a host defence mechanism, which may have favoured selection of a common familial Parkinson's disease mutant allele in the human population.


Subject(s)
Parkinson Disease , Salmonella Infections , Humans , Mice , Animals , Parkinson Disease/genetics , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Salmonella Infections/microbiology , Salmonella/metabolism
7.
Hum Exp Toxicol ; 42: 9603271231173382, 2023.
Article in English | MEDLINE | ID: mdl-37125703

ABSTRACT

Peripheral neurotoxicity injury caused by local anesthetics is a common complication of clinical anesthesia. The study of its mechanism is helpful to prevent and treat the neurotoxic injury of local anesthetics. Previous studies on peripheral neurotoxicity injury caused by local anesthetics have mainly focused on in vitro cell experiments. Due to the lack of an animal model of peripheral neurotoxicity damage caused by local anesthetics, there are few in vivo experimental studies regarding this topic. Herein, 1% ropivacaine hydrochloride was injected into the sciatic nerve by direct incision and exposure of the sciatic nerve to create a local anesthetic neurotoxic injury model. The results showed that 1% ropivacaine hydrochloride could reduce the lower limb motor score and mechanical paw withdrawal threshold in mice 48 hours after injection. Pathological sections showed that 48 hours after treatment with 1% ropivacaine hydrochloride, the sciatic nerve showed increased axonal edema and degeneration, edema between nerve fiber bundles, increased degeneration of axon and myelin sheath vacuoles, edema of nerve bundle membrane and local degeneration and necrosis, and a large number of inflammatory cells around the nerve adventitia were soaked. The above results show that under open vision, 1% ropivacaine hydrochloride can cause injury to the sciatic nerve after 48 h of treatment, which can simulate the neurotoxic damage of local anesthetics. This animal model provides a research tool for studying the mechanism of neurotoxic injury caused by local anesthetics.


Subject(s)
Anesthetics, Local , Models, Animal , Neurotoxicity Syndromes , Animals , Mice , Anesthetics, Local/adverse effects , Anesthetics, Local/toxicity , Edema , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/pathology , Ropivacaine/toxicity , Sciatic Nerve/pathology
8.
Front Oncol ; 13: 1122982, 2023.
Article in English | MEDLINE | ID: mdl-37064141

ABSTRACT

Head and neck squamous cell carcinoma (HNSCC) is the sixth most prevalent malignancy worldwide. Accumulating evidence suggests that persistent HPV infection is closely related to a subset of HNSCC types, and the incidence of human papillomavirus (HPV)-positive HNSCC has been annually increasing in recent decades. Although the carcinogenesis of HPV-positive HNSCC has not been completely elucidated, it has been well confirmed that E6 and E7, the main viral oncoproteins are responsible for the maintenance of malignant transformation, promotion of cell proliferation, and increase in tumor invasion. Moreover, compared with HPV-negative HNSCC, HPV-positive HNSCC shows some special clinical-pathological features, which are possibly related to HPV infection and their specific regulatory mechanisms. Non-coding RNA (ncRNA) is a class of RNA lacking the protein-coding function and playing a critical regulatory role via multiple complex molecular mechanisms. NcRNA is an important regulatory pattern of epigenetic modification, which can exert significant effects on HPV-induced tumorigenesis and progression by deregulating downstream genes. However, the knowledge of ncRNAs is still limited, hence, a better understanding of ncRNAs could provide some insights for exploring the carcinogenesis mechanism and identifying valuable biomarkers in HPV-positive HNSCC. Therefore, in this review, we mainly focused on the expression profile of ncRNAs (including lncRNA, miRNA, and circRNA) and explored their regulatory role in HPV-positive HNSCC, aiming to clarify the regulatory mechanism of ncRNAs and identify valuable biomarkers for HPV-positive HNSCC.

10.
Int Immunopharmacol ; 100: 108142, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34555644

ABSTRACT

The chronic phase following toxin-induced acute kidney injury (AKI) is characterized by robust inflammation and progressive kidney fibrosis. Interferon regulatory factor 4 (IRF-4) is a type of multifunctional transcription factor that has been deeply linked to inflammation and fibrotic diseases. However, the role of IRF-4 in kidney damage and renal fibrosis after toxin-induced AKI remain to be explored. In this work, we examined the effect of IRF-4 deficiency on inflammation and kidney fibrosis in an AKI-chronic kidney disease (CKD) transition model induced by folic acid (FA) injury. We showed that FA treatment resulted in severe acute tubular injury followed by inflammatory reaction and interstitial fibrosis in wild-type mice. A sharp elevation of IRF-4 levels was observed in FA-injured kidneys. IRF-4 knockout led to a substantial reduction of extracellular matrix (ECM) proteins deposition and inhibited myofibroblasts transformation in the kidneys of mice subjected to FA treatment. In addition, IRF-4 ablation impaired F4/80+ macrophages and CD3+ T lymphocytes infiltration into the FA-injured kidneys. Loss of IRF-4 reduced the production of inflammatory molecules such as CXCL16, IL-18, IL-6, and TGF-ß1 in the kidneys in response to FA stress. Following FA injury, the kidneys of IRF-4 knockout mice had fewer bone marrow-derived myofibroblasts than wild-type controls. Moreover, IRF-4 disruption inhibited macrophages to myofibroblasts differentiation in the kidneys in response to FA stimuli. In vitro, IL-4 stimulated expression of α-smooth muscle actin and ECM proteins and promoted M2 macrophages to myofibroblasts transition in mouse bone marrow-derived monocytes, which was abolished in the absence of IRF-4. Thus, we identified an important role of IRF-4 in the pathogenesis of progressive CKD following FA-induced AKI.


Subject(s)
Acute Kidney Injury/metabolism , Interferon Regulatory Factors/deficiency , Kidney/metabolism , Nephritis/metabolism , Renal Insufficiency, Chronic/metabolism , Acute Kidney Injury/chemically induced , Acute Kidney Injury/pathology , Animals , Cell Transdifferentiation , Cells, Cultured , Cytokines/metabolism , Disease Models, Animal , Disease Progression , Extracellular Matrix Proteins/metabolism , Fibrosis , Folic Acid , Inflammation Mediators/metabolism , Interferon Regulatory Factors/genetics , Kidney/pathology , Macrophages/metabolism , Macrophages/pathology , Male , Mice, Inbred C57BL , Mice, Knockout , Myofibroblasts/metabolism , Myofibroblasts/pathology , Nephritis/chemically induced , Nephritis/pathology , Renal Insufficiency, Chronic/chemically induced , Renal Insufficiency, Chronic/pathology
11.
J Vis Exp ; (173)2021 07 16.
Article in English | MEDLINE | ID: mdl-34338666

ABSTRACT

Instead of using genetic methods like RNA interference (RNAi) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated endonuclease Cas9, a physical barrier was microsurgically inserted between the testes of Spodoptera litura to study the impact of this microsurgery on its growth and reproduction. After inserting aluminum foil between the testes, insect molting during metamorphosis proceeded normally. Insect growth and development were not remarkably altered; however, the number of sperm bundles changed if testes fusion was stopped by the microsurgery. These findings imply that blocking testicular fusion can influence male reproduction capability. The method can be further applied to interrupt communication between organs to study the function of specific signaling pathways. Compared to conventional surgery, microsurgery only requires freezing anesthetization, which is preferable to carbon dioxide anesthetization. Microsurgery also minimizes the surgery site area and facilitates wound healing. However, the selection of materials with specific functions needs further investigation. Avoiding tissue injury is crucial when making incisions during the operation.


Subject(s)
CRISPR-Cas Systems , Testis , Animals , Endonucleases , Gene Editing , Male , Spermatozoa , Spodoptera/genetics , Testis/surgery
12.
Oxid Med Cell Longev ; 2021: 8882130, 2021.
Article in English | MEDLINE | ID: mdl-34336116

ABSTRACT

Cardiac microvascular endothelial cell (CMEC) dysfunction is considered as a major contributor to the cardiovascular complications in diabetes mellitus, with oxidative stress caused by hyperglycemia playing a critical role in the progression of CMEC dysfunction. Melatonin is a kind of hormone well known for its antioxidant properties, which has potential protective effects against diabetes mellitus and its complications. However, the role of melatonin on CMEC dysfunction caused by hyperglycemia and its molecular mechanisms underlying these effects has not been clarified. Herein, we investigate the protective effects of melatonin on high glucose- (HG-) evoked oxidative stress and apoptosis in CMECs and underlying mechanisms. Our results revealed that melatonin ameliorated the injury caused by HG in primary cultured rat CMECs. Injury can be accompanied by reduced reactive oxygen species (ROS) and malondialdehyde (MDA) production, and enhanced superoxide dismutase (SOD) activity. Meanwhile, melatonin treatment significantly inhibited HG-induced CMEC apoptosis. Moreover, melatonin increased the activity of the AMPK/SIRT1 signaling axis in CMECs under HG condition, whereas administration of the AMPK inhibitor compound C or SIRT1 silencing partially abrogated the beneficial effects of melatonin. In streptozotocin- (STZ-) evoked diabetic mice, melatonin notably ameliorated cardiac dysfunction and activated the AMPK/SIRT1 signaling. In conclusion, our findings revealed that melatonin attenuates HG-induced CMEC oxidant stress, apoptosis injury, and STZ-induced cardiac dysfunction through regulating the AMPK/SIRT1 signaling pathway.


Subject(s)
AMP-Activated Protein Kinases/drug effects , Antioxidants/therapeutic use , Cardiomyopathies/drug therapy , Melatonin/therapeutic use , Sirtuin 1/drug effects , Animals , Antioxidants/pharmacology , Disease Models, Animal , Humans , Male , Melatonin/pharmacology , Mice , Oxidative Stress , Signal Transduction
13.
Cardiovasc Diagn Ther ; 10(5): 1270-1279, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33224751

ABSTRACT

BACKGROUND: Endothelial progenitor cells (EPCs) play an important role in the re-endothelialization of ischemic cerebrovascular disease. However, the current acquisition method has some deficiencies. This study aimed to design a new and practical method for obtaining EPCs. METHODS: Bone marrow was obtained autologously from the right tibia of living rats. Briefly, the right tibia bone was carefully exposed and two holes (1 mm in diameter) were made in the tuberosity and lower one-third of the tibia, respectively. A PE-50 catheter and syringe (5 mL) were inserted through the holes to aspirate the bone marrow. Bone marrow mononuclear cells (BMMCs) were isolated by density-gradient centrifugation with Ficoll and counted. Adherent cell culture continued for 2 weeks, and the medium was replaced every 3 days. RESULTS: During the first days of culture, adherent cells formed a monolayer, consisting predominantly of small-sized cells. Single large cells with endothelial morphology were observed. On day 4, the nonadherent cells were removed, and the adherent cells were left for further culture. On day 6-7, a proliferating population of round cells formed clusters in the culture chamber, and morphological analysis revealed a homogeneous population of colony-forming units (CFUs). Large, flat cells with endothelial morphology sprouted from the CFUs, which had nearly disappeared by day 14 of culture. The adherent cells were positive for CD133 and vascular endothelial growth factor receptor 2 (VEGFR2), internalized acetylated low-density lipoprotein, and bound ulex europaeus-agglutinin-I, but were negative for CD45, which correlated with the endothelial morphology and ability to form capillaries of EPCs. CONCLUSIONS: Our results are direct evidence that mononuclear cells (MCS) from living rat bone marrow can be used to culture EPCs in vitro under certain culture conditions, providing a new method for the further study of autologous EPC transplantation.

14.
Science ; 369(6502): 450-455, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32703879

ABSTRACT

The guanosine triphosphatase (GTPase) Rab32 coordinates a cell-intrinsic host defense mechanism that restricts the replication of intravacuolar pathogens such as Salmonella Here, we show that this mechanism requires aconitate decarboxylase 1 (IRG1), which synthesizes itaconate, a metabolite with antimicrobial activity. We find that Rab32 interacts with IRG1 on Salmonella infection and facilitates the delivery of itaconate to the Salmonella-containing vacuole. Mice defective in IRG1 rescued the virulence defect of a S. enterica serovar Typhimurium mutant specifically defective in its ability to counter the Rab32 defense mechanism. These studies provide a link between a metabolite produced in the mitochondria after stimulation of innate immune receptors and a cell-autonomous defense mechanism that restricts the replication of an intracellular bacterial pathogen.


Subject(s)
Hydro-Lyases/immunology , Salmonella Infections/immunology , Salmonella enterica , Salmonella typhimurium , rab GTP-Binding Proteins/immunology , Animals , Cell Line , Host-Pathogen Interactions , Humans , Hydro-Lyases/metabolism , Mice , Salmonella Infections/metabolism , Salmonella Infections/microbiology , Succinates , Virulence , rab GTP-Binding Proteins/metabolism
15.
Adv Sci (Weinh) ; 7(1): 1901261, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31921549

ABSTRACT

The noncanonical NF-κB signaling pathway plays a critical role in a variety of biological functions including chronic inflammation and tumorigenesis. Activation of noncanonical NF-κB signaling largely relies on the abundance as well as the processing of the NF-κB family member p100/p52. Here, TRIM14 is identified as a novel positive regulator of the noncanonical NF-κB signaling pathway. TRIM14 promotes noncanonical NF-κB activation by targeting p100/p52 in vitro and in vivo. Furthermore, a mechanistic study shows that TRIM14 recruits deubiquitinase USP14 to cleave the K63-linked ubiquitin chains of p100/p52 at multiple sites, thereby preventing p100/p52 from cargo receptor p62-mediated autophagic degradation. TRIM14 deficiency in mice significantly impairs noncanonical NF-κB-mediated inflammatory responses as well as acute colitis and colitis-associated colon cancer development. Taken together, these findings establish the TRIM14-USP14 axis as a crucial checkpoint that controls noncanonical NF-κB signaling and highlight the crosstalk between autophagy and innate immunity.

16.
Eur J Clin Microbiol Infect Dis ; 37(2): 363-369, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29214503

ABSTRACT

Human coronaviruses (HCoV) OC43, 229E, NL63, and HKU1 are common respiratory viruses which cause various respiratory diseases, including pneumonia. There is a paucity of evidence on the epidemiology and clinical manifestations of these four HCoV strains worldwide. We collected 11,399 throat swabs from hospitalized children with acute respiratory tract infection from July 2009 to June 2016 in Guangzhou, China. These were tested for four strains of HCoV infection using real-time polymerase chain reaction (PCR). HCoV-positive patients were then tested for 11 other respiratory pathogens. 4.3% (489/11399) of patients were positive for HCoV, of which 3.0% were positive for OC43 (346/11399), 0.6% for 229E (65/11399), 0.5% for NL63 (60/11399), and 0.3% for HKU1 (38/11399). Patients aged 7-12 months had the highest prevalence of HCoV and OC43 when compared with other age groups (p < 0.001). The peak seasons of infection varied depending on the HCoV strain. Patients infected with a single strain of HCoV infection were less likely to present fever (≥ 38 °C) (p = 0.014) and more likely to present pulmonary rales (p = 0.043) than those co-infected with more than one HCoV strain or other respiratory pathogens. There were also significant differences in the prevalence of certain symptoms, including coughing (p = 0.032), pneumonia (p = 0.026), and abnormal pulmonary rales (p = 0.002) according to the strain of HCoV detected. This retrospective study of the prevalence of four HCoV strains and clinical signs among a large population of pediatric patients in a subtropical region of China provides further insight into the epidemiology and clinical features of HCoV.


Subject(s)
Coronavirus 229E, Human/isolation & purification , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Coronavirus NL63, Human/isolation & purification , Coronavirus OC43, Human/isolation & purification , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Adolescent , Child , Child, Preschool , China/epidemiology , Coronavirus Infections/virology , Female , Humans , Infant , Infant, Newborn , Male , Prevalence , Real-Time Polymerase Chain Reaction , Respiratory Tract Infections/virology , Retrospective Studies
17.
Mol Cell ; 64(1): 105-119, 2016 10 06.
Article in English | MEDLINE | ID: mdl-27666593

ABSTRACT

Cyclic GMP-AMP synthase (cGAS) is an essential DNA virus sensor that triggers type I interferon (IFN) signaling by producing cGAMP to initiate antiviral immunity. However, post-translational regulation of cGAS remains largely unknown. We report that K48-linked ubiquitination of cGAS is a recognition signal for p62-depdendent selective autophagic degradation. The induction of TRIM14 by type I IFN accelerates cGAS stabilization by recruiting USP14 to cleave the ubiquitin chains of cGAS at lysine (K) 414. Knockout of TRIM14 impairs herpes simplex virus type 1 (HSV-1)-triggered antiviral responses in a cGAS-dependent manner. Due to impaired type I IFN production, Trim14-/- mice are highly susceptible to lethal HSV-1 infection. Taken together, our findings reveal a positive feedback loop of cGAS signaling generated by TRIM14-USP14 and provide insights into the crosstalk between autophagy and type I IFN signaling in innate immunity.


Subject(s)
Herpes Simplex/genetics , Immunity, Innate , Nucleotidyltransferases/genetics , Protein Processing, Post-Translational , Sequestosome-1 Protein/genetics , Trans-Activators/genetics , Ubiquitin Thiolesterase/genetics , Animals , Autophagy/drug effects , Feedback, Physiological , HEK293 Cells , Herpes Simplex/immunology , Herpes Simplex/mortality , Herpes Simplex/virology , Herpesvirus 1, Human/growth & development , Herpesvirus 1, Human/immunology , Host-Pathogen Interactions , Humans , Interferon Type I/pharmacology , Intracellular Signaling Peptides and Proteins , Lung/drug effects , Lung/immunology , Lung/virology , Mice , Mice, Knockout , Nucleotidyltransferases/immunology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Sequestosome-1 Protein/immunology , Signal Transduction , Survival Analysis , Trans-Activators/immunology , Tripartite Motif Proteins , Ubiquitin Thiolesterase/antagonists & inhibitors , Ubiquitin Thiolesterase/deficiency
18.
PLoS One ; 10(9): e0138684, 2015.
Article in English | MEDLINE | ID: mdl-26406339

ABSTRACT

BACKGROUND: Respiratory tract infections (RTIs) are a heavy burden on society. However, due to the complex etiology of RTIs, the clinical diagnosis, treatment, and prevention of these infections remain challenging, especially in developing countries. METHODS: To determine the epidemiological and clinical characteristics of 18 respiratory pathogens, we analyzed 12,502 patients with acute respiratory infections (ARIs) by performing polymerase chain reaction (PCR) on patient pharyngeal swabs. RESULTS: Samples positive for at least 1 pathogen were obtained from 48.42% of the total patients. Of these pathogen-positive patients, 17.99% were infected with more than 1 pathogen. Of the 18 pathogens analyzed, four were detected with a positive detection rate (PDR) > 5%: influenza A virus (IAV) > respiratory syncytial virus (RSV) >Mycoplasma pneumoniae (MP) > human coronavirus (HCoV). The pathogens with the 4 highest co-infection rates (CIRs) were as follows: HCoV > human bocavirus (HBoV) > enterovirus (EV) > parainfluenza virus (PIV). The overall positive detection rate (PDR) varied significantly according to patient age, the season and year of detection, and the disease subgroup, but not according to patient sex. The individual PDRs of the pathogens followed 3 types of distributions for patient sex, 4 types of distributions for patient age, 4 types of seasonal distributions, 2 types of seasonal epidemic trends, 4 types of yearly epidemic trends, and different susceptibility distributions in the disease subgroups. Additionally, the overall CIR showed significantly different distributions according to patient sex, patient age, and the disease subgroup, whereas the CIRs of individual pathogens suggested significant preference characteristics. CONCLUSION: IAV remains the most common pathogen among the pathogens analyzed. More effort should be directed toward the prevention and control of pathogens that show a trend of increasing incidence such as HCoV, human adenovirus (ADV), and RSV. Although clinically distinguishing specific pathogens responsible for RTIs is difficult, the epidemiological and clinical characteristics of the various RTI-causing agents could provide clues for clinicians, thereby informing decisions regarding prevention and medication and guiding appropriate public health strategies.


Subject(s)
Bacteria/classification , Pharynx/microbiology , Respiratory Tract Infections/classification , Respiratory Tract Infections/epidemiology , Viruses/classification , Adolescent , Adult , Bacteria/genetics , Bacteria/isolation & purification , Child , Child, Preschool , China/epidemiology , Female , Hospitalization , Humans , Infant , Infant, Newborn , Male , Middle Aged , Respiratory Tract Infections/microbiology , Seasons , Viruses/genetics , Viruses/isolation & purification , Young Adult
19.
Aust N Z J Obstet Gynaecol ; 52(4): 387-90, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22676439

ABSTRACT

AIMS: To analyse the optimal laparoscopic surgical techniques for the treatment of interstitial pregnancy to minimise bleeding during the operative procedure and the safety of the subsequent pregnancy. METHODS: Advanced bipolar coagulator was used to achieve haemostasis. RESULTS: The mean gestational age was 55 ± 5.1 days. All 17 women with an interstitial pregnancy were successfully treated by laparoscopic surgery without any complication. No surgery was converted to laparotomy. The mean pre-operative beta-human chorionic gonadotropin (ß-hCG) serum concentration was 14 696 ± 11 705 mIU/mL. This value decreased to 1911 ± 1769 mIU/mL at 3-day post-operation. Among women who underwent laparoscopic surgery, a cornual resection was performed in 16 (94.1%) cases. One (5.8%) woman underwent a laparoscopic evacuation of the conceptus and received a local injection of 10 mg methotrexate. The volume of blood loss was <25 mL in 16 cases. However, one woman experienced a rupture at the beginning of the operation and lost 250 mL of blood. The mean hospital stay was 4.5 days. Four of the nine women who chose to retain their reproductive function had subsequent normal pregnancies, but all received an elective caesarean delivery prior to labour. CONCLUSIONS: The laparoscopic management of women with unruptured interstitial pregnancy can frequently be performed without haemorrhage or complication using advanced bipolar coagulation. The small sample of successful subsequent pregnancies demonstrates the safety and effectiveness of this technique, but this finding should be confirmed by further investigations.


Subject(s)
Laparoscopy/methods , Methotrexate/therapeutic use , Pregnancy, Ectopic/surgery , Abortifacient Agents, Nonsteroidal/therapeutic use , Adult , Blood Loss, Surgical/prevention & control , Female , Gestational Age , Humans , Laparoscopy/adverse effects , Postoperative Period , Pregnancy , Pregnancy, Ectopic/drug therapy , Retrospective Studies , Treatment Outcome
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