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1.
Int J Antimicrob Agents ; 63(4): 107101, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38325722

ABSTRACT

BACKGROUND: Resistance to extended-spectrum cephalosporins (ESCs) has become a public health concern with the spread of Neisseria gonorrhoeae and increasing antimicrobial resistance. Mutation of penA, encoding penicillin-binding protein 2, represents a mechanism of ESC resistance. This study sought to assess penA alleles and mutations associated with decreased susceptibility (DS) to ESCs in N. gonorrhoeae. MATERIALS AND METHODS: In 2021, 347 gonococci were collected in Guangdong, China. Minimum inhibitory concentations (MICs) of ceftriaxone and cefixime were determined, and whole-genome sequencing and phylogenetic analysis were performed. Multi-locus sequence typing (MLST) and conventional resistance determinants such as penA, mtrR, PonA and PorB were analysed. penA was genotyped and sequence-aligned using PubMLST. RESULTS: Genome-wide phylogenetic analysis revealed that the prevalence of DS to ESCs was highest in Clade 11.1 (100.0%), Clade 2 (66.7%) and Clade 0 (55.7%), and the leading cause was strains with penA-60.001 or new penA alleles in clades. The penA phylogenetic tree is divided into two branches: non-mosaic penA and mosaic penA. The latter contained penA-60.001, penA-10 and penA-34. penA profile analysis indicated that A311V and T483S are closely related to DS to ESCs in mosaic penA. The new alleles NEIS1753_2840 and NEIS1753_2837 are closely related to penA-60.001, with DS to ceftriaxone and cefixime of 100%. NEIS1753_2660, a derivative of penA-10 (A486V), has increased DS to ceftriaxone. NEIS1753_2846, a derivative of penA-34.007 (G546S), has increased DS to cefixime. CONCLUSION: This study identified critical penA alleles related to elevated MICs, and trends of gonococcus-evolved mutated penA associated with DS to ESCs in Guangdong.


Subject(s)
Ceftriaxone , Gonorrhea , Humans , Ceftriaxone/pharmacology , Cefixime/pharmacology , Neisseria gonorrhoeae/genetics , Anti-Bacterial Agents/pharmacology , Multilocus Sequence Typing , Alleles , Phylogeny , Gonorrhea/drug therapy , Gonorrhea/epidemiology , Microbial Sensitivity Tests , Cephalosporins/pharmacology , China/epidemiology
2.
Ann Clin Microbiol Antimicrob ; 22(1): 39, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37198645

ABSTRACT

BACKGROUND: Antimicrobial resistance (AMR) of untreatable gonococcal infection is an emerging threat, especially in Guangdong, a prosperous province in Southern China. METHODS: N.gonorrhoeae was isolated from 20 cities in Guangdong and determined antimicrobial susceptibility. Through whole-genome sequencing (WGS), multilocus sequence typing (MLST), N.gonorrhoeae multiantigen sequence typing (NG-MAST), and N.gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) were obtained based on the PubMLST database ( https://pubmlst.org/ ). Phylogenetic analysis was used for dissemination and tracking analysis. RESULTS: Antimicrobial susceptibility was performed on 347 isolates, and 50 isolates were identified as decreased susceptibility (DS) to cephalosporins. Of which 16.0% (8/50) were ceftriaxone DS, 38.0% (19/50) were cefixime DS, and 46.0% (23/50) were both ceftriaxone and cefixime DS. In all, the dual-resistant rate of the cephalosporin-DS isolates was 96.0% for penicillin and 98.0% for tetracycline-resistant, and 10.0% (5/50) were resistant to azithromycin. All cephalosporin-DS isolates were resistant to ciprofloxacin but sensitive to spectinomycin. The predominant MLSTs were ST7363 (16%, 8/50), ST1903 (14%, 7/50), ST1901 (12%, 6/50), and ST7365 (10%, 5/50). Besides some isolates that failed genotyping (NA), NG-STAR ST1143 (n = 6) and NG-MAST ST17748 (n = 4) were the most prevalent. Twelve isolates with mosaic penA-60.001 allele retained the most elevated cephalosporin MIC (Minimum Inhibitory Concentration). Phylogenetic analysis revealed that epidemic penA-60.001 clones, either domestic or foreign, had spread to nine cities in Guangdong, and 9/12 clones were from the Pearl River Delta region. CONCLUSIONS: N. gonorrhoeae with cephalosporins-DS was extensively disseminated in Guangdong, Southern China, requiring strict surveillance.


Subject(s)
Cephalosporins , Gonorrhea , Humans , Cephalosporins/pharmacology , Neisseria gonorrhoeae/genetics , Ceftriaxone/pharmacology , Cefixime/pharmacology , Multilocus Sequence Typing , Phylogeny , Cities , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Gonorrhea/epidemiology , Gonorrhea/drug therapy , Microbial Sensitivity Tests
3.
Cell Death Dis ; 14(4): 280, 2023 04 20.
Article in English | MEDLINE | ID: mdl-37080972

ABSTRACT

Septins as GTPases in the cytoskeleton, are linked to a broad spectrum of cellular functions, including cell migration and the progression of hepatocellular carcinoma (HCC). However, roles of SEPT11, the new member of septin, have been hardly understood in HCC. In the study, the clinical significance and biological function of SEPT11 in HCC was explored. SEPT11 was screened out by combining ATAC-seq with mRNA-seq. Role of SEPT11 in HCC was further investigated by using overexpression, shRNA and CRISPR/Cas9-mediated SEPT11-knockout cells or in vivo models. We found RNA-seq and ATAC-seq highlights LncRNA AY927503 (AY) induced SEPT11 transcription, resulting in Rho GTPase activation and cytoskeleton actin aggregation. The GTP-binding protein SEPT11 is thus considered, as a downstream factor of AY, highly expressed in various tumors, including HCC, and associated with poor prognosis of the patients. In vitro, SEPT11 overexpression promotes the migration and invasion of HCC cells, while SEPT11-knockout inhibits migration and invasion. In vivo, SEPT11-overexpressed HCC cells show high metastasis incidents but don't significantly affect proliferation. Meanwhile, we found SEPT11 targets RhoA, thereby regulating cytoskeleton rearrangement and abnormal cell adhesion through ROCK1/cofilin and FAK/paxillin signaling pathways, promoting invasion and migration of HCC. Further, we found SEPT11 facilitates the binding of GEF-H1 to RhoA, which enhances the activity of RhoA. Overall, our study confirmed function of SEPT11 in promoting metastasis in HCC, and preliminarily explored its related molecular mechanism. SEPT11 acts as an oncogene in HCC, also draws further interest regarding its clinical application as a potential therapeutic target.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/pathology , Cell Adhesion/genetics , Cell Line, Tumor , Cell Movement/genetics , Cytoskeleton/metabolism , Liver Neoplasms/pathology , rho-Associated Kinases/genetics , rho-Associated Kinases/metabolism , rhoA GTP-Binding Protein/genetics , rhoA GTP-Binding Protein/metabolism
4.
Front Nutr ; 9: 1062671, 2022.
Article in English | MEDLINE | ID: mdl-36532523

ABSTRACT

Moringa oleifera leaves are a kind of new food raw materials, rich in functional factors, M. oleifera leaves aqueous extract have antioxidant activity and M. oleifera leave protein is an important active ingredient in the aqueous extract. Numerous studies have shown that peptides have strong antioxidant activity. To reveal the antioxidant effects of M. oleifera (MO) leaves peptides, MO leave antioxidant peptides were isolated and prepared to clarify their antioxidant activity. MLPH1 (<1 kDa), MLPH3 (1~3 kDa), MLPH5 (3~5 kDa), and MLPH10 (5~10 kDa) fractions were obtained by the membrane ultrafiltration classification of MO leaves proteolytic hydrolysate (MLPH). MLPH1 was further separated by centrifugal filters, and the fraction separated by <1 kDa (MLPH1-1) was identified and analyzed by LC-MS/MS. The purpose of this study was to investigate the effect of MO leaves antioxidant peptide pretreatment on H2O2-treated HepG2 cells and to refine the antioxidant activity. The results showed that MLPH1 had the strongest antioxidant activity, and three MO leaves antioxidant peptides (LALPVYN, LHIAALVFQ, and FHEEDDAKLF) were obtained. The peptide with the sequence LALPVYN and a molecular weight of 788.44 Da had the strongest antioxidant activity. After 24 h of LALPVYN pretreatment, the cell viability and the CAT, GSH-Px, and SOD enzyme activity were significantly increased, and the MDA, ROS, and apoptosis rates were significantly decreased. These results provide a theoretical basis for further research on the antioxidant mechanism of MO leaves peptides.

5.
Microbiol Spectr ; 10(6): e0157022, 2022 12 21.
Article in English | MEDLINE | ID: mdl-36377922

ABSTRACT

Currently, antibiotic resistance (especially ceftriaxone and azithromycin dual resistance) in Neisseria gonorrhoeae is the main obstacle affecting the efficacy of treatment. As analysis of drug sensitivity, molecular features, and dissemination of dual-resistant strains is important for gonococcal prevention and control, MIC, genotyping, and genome analysis were conducted to reveal the molecular characteristics and phylogeny of N. gonorrhoeae isolates. During 2016 to 2019, 5 out of 4,113 strains were defined as dual-resistant clones, with ceftriaxone MICs of 0.25 to ≥1 mg/L and azithromycin MICs of 2 to ≥2,048 mg/L. In particular, two strains with a ceftriaxone MIC above 0.5 mg/L were characterized as penA-60.001 FC428-related clones, and two isolates with a high-level azithromycin MIC above 1,024 mg/L featuring a 23S rRNA mutation were identified. Furthermore, phylogenetic analysis confirmed that the dual-resistant strains were closer to the evolutionary origin of F89 in France, global FC428-related clones, and high-level dual-resistant clones in Australia and the United Kingdom. Dual-resistant strains, including FC428-related clones and high-level azithromycin-resistant clones, have circulated in Guangdong, China. The ability of laboratories to perform real-time drug susceptibility and genetic analyses should be strengthened to monitor the spread of threatening strains. IMPORTANCE Here, we report five sporadic dual-resistant isolates, including FC428-related ceftriaxone-resistant clones with MICs of ≥0.5 mg/L and high-level azithromycin resistance with MICs of ≥1,024 mg/L. This study highlights that dual-resistant clones with the same evolutionary origin as FC428, A2735, and F89 have circulated in Guangdong, China, which suggests that the capacity for antibiotic resistance testing and genome analysis should be strengthened in daily epidemiological surveillance.


Subject(s)
Ceftriaxone , Gonorrhea , Humans , Ceftriaxone/pharmacology , Ceftriaxone/therapeutic use , Azithromycin/pharmacology , Azithromycin/therapeutic use , Neisseria gonorrhoeae/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Phylogeny , Gonorrhea/epidemiology , Gonorrhea/drug therapy , Drug Resistance, Bacterial/genetics , Microbial Sensitivity Tests , Genomics , China/epidemiology
6.
Antioxidants (Basel) ; 11(11)2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36421438

ABSTRACT

Urotensin II (UII) could increase blood pressure and heart rate via increased central reactive oxygen species (ROS) levels. We reported previously that hydrogen sulfide (H2S) exerts an antihypertensive effect by suppressing ROS production. The aim of the current study is to further examine the effects of endogenous and exogenous H2S on UII-induced cardiovascular effects by using an integrated physiology approach. We also use cell culture and molecular biological techniques to explore the inhibitory role of H2S on UII-induced cardiovascular effects. In this study, we found that cystathionine-ß-synthase (CBS), the main H2S synthesizing enzyme in CNS, was expressed in neuronal cells of the rostral ventrolateral medulla (RVLM) area. Cellular distribution of CBS and urotensin II receptor (UT) in SH-SY5Y cells that are confirmed as glutamatergic were identified by immunofluorescent and Western blots assay. In Sprague-Dawley rats, administration of UII into the RVLM resulted in an increase in mean arterial pressure (MAP), heart rate (HR), ROS production, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, and phosphorylation of p47phox, extracellular signal-regulated protein kinase (ERK)1/2 and p38MAPK, but not stress-activated protein kinase/Jun N-terminal kinase (SAPK/JNK). These effects of UII were attenuated by application into the RVLM of endogenous (L-cysteine, SAM) or exogenous (NaHS) H2S. These results were confirmed in SH-SY5Y cells. UII-induced cardiovascular effects were also significantly abolished by pretreatment with microinjection of Tempol, Apocynin, SB203580, or PD98059 into the RVLM. Preincubated SH-SY5Y cells with Apocynin before administration of UII followed by Western blots assay showed that ROS is in the upstream of p38MAPK/ERK1/2. Gao activation assay in SH-SY5Y cells suggested that H2S may exert an inhibitory role on UII-induced cardiovascular effects by inhibiting the activity of Gαo. These results suggest that both endogenous and exogenous H2S attenuate UII-induced cardiovascular effects via Gαo-ROS-p38MAPK/ERK1/2 pathway.

7.
Int J Mol Sci ; 23(20)2022 Oct 17.
Article in English | MEDLINE | ID: mdl-36293262

ABSTRACT

Moringa oleifera leaves (MOL) are a new food resource, rich in functional factors. MOL polysaccharides are important active macromolecules within MOL. However, there are problems, such as low extraction rates and lack of evidence for functional activity. Therefore, in this experiment, single-factor experiments were carried out using MOL powder as the raw material, and the Plackett-Burman test was used to screen the significantly influential test factors. The extraction process of MOL polysaccharide was optimized by response surface methodology. The insulin resistance alleviating activity of MOLP polysaccharides was initially explored. The results showed that the extraction of Moringa oleifera leaves crude polysaccharides (MOLP) by ultrasonic assisted cellulase enzymatic digestion was (17.03 ± 1.03)%, and the obtained MOLP was a crude polysaccharide with an average molecular weight (Mw) of 279.48 kDa, consisting of fucose, rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. MOLP had an IC50 value of 8.02 mg/mL for α-glucosidase and scavenging activity against free radicals such as ABTS, DPPH, hydroxyl radicals, and superoxide anion with an IC50 value of 0.21 mg/mL 0.31 mg/mL 0.97 mg/mL 0.49 mg/mL. At the same time, MOLP significantly enhanced the glucose consumption, glycogen synthesis, CAT, SOD, GSH-Px activity, and reduced the MDA and ROS content in high glucose-induced insulin-resistant HepG2 (IR-HepG2) cells. This experiment improved the extraction rate of MOLP and demonstrated that MOLP has antioxidant activity and α-glucosidase inhibitory activity, which can alleviate the insulin resistance of high glucose-induced HepG2 cells. It provides partial data support for the possible hypoglycemic effect of MOLP by alleviating oxidative stress, and also provides new ideas for the in-depth study of basic research and industrial application of MOLP.


Subject(s)
Cellulase , Insulin Resistance , Insulins , Moringa oleifera , Humans , Antioxidants/pharmacology , Antioxidants/chemistry , alpha-Glucosidases , Hep G2 Cells , Ultrasonics , Fucose , Galactose , Reactive Oxygen Species , Arabinose , Rhamnose , Mannose , Superoxides , Xylose , Powders , Polysaccharides/pharmacology , Polysaccharides/chemistry , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/chemistry , Glucose , Glucuronic Acid , Glycogen , Superoxide Dismutase
8.
Antimicrob Agents Chemother ; 66(4): e0229421, 2022 04 19.
Article in English | MEDLINE | ID: mdl-35345891

ABSTRACT

The emergence of multidrug resistance in Neisseria gonorrhoeae is concerning, especially the cooccurrence of azithromycin resistance and decreased susceptibility to extended-spectrum cephalosporin. This study aimed to confirm the antibiotic resistance trends and provide a solution for N. gonorrhoeae treatment in Guangdong, China. A total of 5,808 strains were collected for assessment of antibiotic MICs. High resistance to penicillin (53.80 to 82%), tetracycline (88.30 to 100%), ciprofloxacin (96 to 99.8%), cefixime (6.81 to 46%), and azithromycin (8.60 to 20.03%) was observed. Remarkably, spectinomycin and ceftriaxone seemed to be the effective choices, with resistance rates of 0 to 7.63% and 2.00 to 16.18%, respectively. Moreover, the rates of azithromycin resistance combined with decreased susceptibility to ceftriaxone and cefixime reached 9.28% and 8.64%, respectively. Furthermore, genotyping identified NG-STAR-ST501, NG-MAST-ST2268, and MLST-ST7363 as the sequence types among representative multidrug-resistant isolates. Evolutionary analysis showed that FC428-related clones have spread to Guangdong, China, which might be a cause of the rapid increase in extended-spectrum cephalosporin resistance currently. Among these strains, the prevalence of N. gonorrhoeae was extremely high, and single-dose ceftriaxone treatment might be a challenge in the future. To partially relieve the treatment pressure, a susceptibility test for susceptibility to azithromycin plus extended-spectrum cephalosporin dual therapy was performed. The results showed that all the representative isolates could be effectively killed with the coadministration of less than 1 mg/liter azithromycin and 0.125 mg/liter extended-spectrum cephalosporin, with a synergistic effect according to a fractional inhibitory concentration (FIC) of <0.5. In conclusion, dual therapy might be a powerful measure to treat refractory N. gonorrhoeae in the context of increasing antibiotic resistance in Guangdong, China.


Subject(s)
Gonorrhea , Neisseria gonorrhoeae , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Azithromycin/pharmacology , Azithromycin/therapeutic use , Cefixime/pharmacology , Ceftriaxone/pharmacology , Ceftriaxone/therapeutic use , Cephalosporin Resistance , Cephalosporins/pharmacology , Cephalosporins/therapeutic use , China/epidemiology , Drug Resistance, Bacterial , Gonorrhea/drug therapy , Gonorrhea/epidemiology , Humans , Microbial Sensitivity Tests , Multilocus Sequence Typing
9.
Emerg Microbes Infect ; 11(1): 344-350, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34994305

ABSTRACT

Background: After Neisseria gonorrhoeae FC428 was first found in Japan, ceftriaxone-resistant strains disseminated globally, and the gonococcal resistance rate increased remarkably. Epidemiological investigations are greatly significant for the analysis of antimicrobial resistance (AMR) trends, molecular features and evolution. Objectives: To clarify the AMR trend from 2016-2019 and reveal the molecular characteristics and evolution of ceftriaxone-resistant penA 60.001 isolates. Methods: The minimum inhibitory concentrations (MICs) of antibiotics against 4113 isolates were detected by the agar dilution method. N. gonorrhoeae multiantigen sequence typing (NG-MAST), multilocus sequence typing (MLST) and N.gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) were used to identify the sequence types. Genome analysis was conducted to analyze resistance genes, virulence factors, and evolutionary sources. Results: Isolates with decreased ceftriaxone susceptibility have increased from 2.05% (2016) to 16.18% (2019). Six ceftriaxone-resistant isolates possessing penA 60.001 appeared in Guangdong Province, and were resistant to ceftriaxone, penicillin, tetracycline, ciprofloxacin and cefixime, but susceptible to azithromycin and spectinomycin. Single-nucleotide polymorphisms (SNPs) in the porB gene were the major cause of different NG-MAST types. ST1903 was the main NG-STAR genotype and only strain-ZH545 was ST7365, with molecular features consistent with the MICs. Furthermore, different MLSTs suggested diverse evolutionary sources. Genome analysis revealed a set of virulence factors along with the resistance genes "penA" and "blaTEM-1B". Half of penA 60.001 strains were fully mixed with global FC428-related strains. Conclusions: Global FC428-related clones have disseminated across Guangdong, possibly causing decreased ceftriaxone susceptibility. Enhanced gonococcal surveillance will help elucidate the trajectory of transmission and curb further dissemination.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ceftriaxone/pharmacology , Gonorrhea/microbiology , Neisseria gonorrhoeae/drug effects , Azithromycin/pharmacology , China/epidemiology , Ciprofloxacin/pharmacology , Drug Resistance, Bacterial , Genome, Bacterial , Gonorrhea/drug therapy , Humans , Microbial Sensitivity Tests , Molecular Epidemiology , Multilocus Sequence Typing , Neisseria gonorrhoeae/classification , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/isolation & purification , Spectinomycin/pharmacology
10.
Biomed Res Int ; 2021: 4873678, 2021.
Article in English | MEDLINE | ID: mdl-34337013

ABSTRACT

LIHC (liver hepatocellular carcinoma) mostly occurs in patients with chronic liver disease. It is primarily induced by a vicious cycle of liver injury, inflammation, and regeneration that usually last for decades. The G protein nucleolar 2 (GNL2), as a protein-encoding gene, is also known as NGP1, Nog2, Nug2, Ngp-1, and HUMAUANTIG. Few reports are shown towards the specific biological function of GNL2. Meanwhile, it is still unclear whether it is related to the pathogenesis of carcinoma up to date. Here, our study attempts to validate the role and function of GNL2 in LIHC via multiple databases and functional assays. After analysis of gene expression profile from The Cancer Genome Atlas (TCGA) database, GNL2 was largely heightened in LIHC, and its overexpression displayed a close relationship with different stages and poor prognosis of carcinoma. After enrichment analysis, the data revealed that the genes coexpressed with GNL2 probably participated in ribosome biosynthesis which was essential for unrestricted growth of carcinoma. Cell functional assays presented that GNL2 knockdown by siRNA in LIHC cells MHCC97-H and SMCC-7721 greatly reduced cell proliferation, migration, and invasion ability. All in all, these findings capitulated that GNL2 could be a promising treatment target and prognosis biomarker for LIHC.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/therapy , GTP-Binding Proteins/metabolism , Liver Neoplasms/metabolism , Liver Neoplasms/therapy , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Down-Regulation/genetics , GTP-Binding Proteins/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Gene Ontology , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Prognosis , Reproducibility of Results , Signal Transduction/genetics
11.
Infect Drug Resist ; 13: 1775-1780, 2020.
Article in English | MEDLINE | ID: mdl-32606827

ABSTRACT

INTRODUCTION: Antimicrobial resistance (AMR) of Neisseria gonorrhoeae (N. gonorrhoeae) becomes a grave public health problem in the world. A strengthened Antimicrobial Resistance Surveillance Program is needed to track the trend of AMR development. However, the lack of a proper antimicrobial susceptibility test (AST) method is a barrier to expand the AMR surveillance in China. Traditional agar dilution (AD) method is laborious and E-test strips have no approval license for clinical use. Herein, a Chinese group modified the microdilution (MD) method for clinical ASTs. The objective of this study is to compare the MD method with the AD method for N. gonorrhoeae AST. MATERIALS AND METHODS: A total of 166 clinical isolates were tested for antimicrobial susceptibility of ceftriaxone, spectinomycin, azithromycin, ciprofloxacin, tetracycline, and penicillin using MD and AD method simultaneously. Results of MD method were read manually or automatically. Rates of essential agreement (EA), category agreement (CA), minor error, and very major error were compared. RESULTS: The total EAs (compared with results read manually) of penicillin, tetracycline, ciprofloxacin, spectinomycin, ceftriaxone, and azithromycin were 90.4%, 97.0%, 85.5%, 100.0%, 94%, and 72.3%; and CAs were 82.5%, 94.0%, 100%, 100%, 95.2%, and 94%, respectively. CONCLUSION: We conclude that the MD method might be an alternative for clinical AST of N. gonorrhoeae in China. In particular, MD method has the potency of accurate differentiation of isolates resistant to ceftriaxone or azithromycin, which were empirically recommended for gonococcal treatment, but its quality remained suboptimal, and further improvement is needed for clinical use.

12.
Int J Antimicrob Agents ; 54(6): 757-765, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31425792

ABSTRACT

The prevalence of Neisseria gonorrhoeae infections has increased rapidly since 2015 in China. Antimicrobial resistance and molecular mobilisation in N. gonorrhoeae are two important factors driving this increasing prevalence. This study explored changes in antimicrobial susceptibility and molecular characteristics of N. gonorrhoeae collected in Guangdong, China (2013-2017). A total of 704 isolates were collected in two cities in Guangdong. MICs of major antimicrobials were determined. Penicillinase-producing N. gonorrhoeae (PPNG) and tetracycline-resistant N. gonorrhoeae (TRNG) were characterised, and N. gonorrhoeae multiantigen sequence typing (NG-MAST) was performed. High resistance to penicillin (68.2%), tetracycline (85.7%) and ciprofloxacin (98.2%) was observed. Spectinomycin, ceftriaxone and azithromycin appeared effective, with susceptibilities of 100%, 96.4% and 90.7%, respectively. Resistance to penicillin decreased significantly from 78.4% to 73.6% and to azithromycin from 11.9% to 3.7%. Total prevalence of PPNG, TRNG and PPNG/TRNG was 25.4%, 33.1% and 13.4%, respectively. Rates of PPNG decreased significantly from 37.3% to 23.9%, TRNG from 50.0% to 31.3%, and PPNG/TRNG from 23.5% to 11.7%. However, the ratio of African-type PPNG increased significantly (18.4% to 64.1%) compared with decreasing Asian-type PPNG (81.6% to 33.3%), and the ratio of American-type TRNG increased significantly (0% to 13.7%) compared with decreasing Dutch-type TRNG (100% to 86.3%). A total of 271 sequence types (STs) were identified by NG-MAST from 380 isolates collected in 2013, 2014 and 2017, with 145 novel STs. African-type PPNG is increasing and replacing Asian-type, and novel STs have emerged. Gonococcal isolates with new genotypes might contribute to the rising gonorrhoea epidemic in this area.


Subject(s)
Epidemics , Gonorrhea/epidemiology , Gonorrhea/microbiology , Neisseria gonorrhoeae/drug effects , Anti-Bacterial Agents/pharmacology , China/epidemiology , Drug Resistance, Multiple, Bacterial , Genotype , Humans , Microbial Sensitivity Tests , Molecular Epidemiology , Neisseria gonorrhoeae/genetics , Prevalence , Time Factors
13.
J Glob Antimicrob Resist ; 16: 202-209, 2019 03.
Article in English | MEDLINE | ID: mdl-30321622

ABSTRACT

OBJECTIVES: The aim of the study is to identify ceftriaxone resistance-related genes in Neisseria gonorrhoeae. METHODS: Differences in gene expression were compared between ceftriaxone-susceptible N. gonorrhoeae isolates [minimum inhibitory concentration (MIC)=0.002-0.004mg/L] and isolates with decreased ceftriaxone susceptibility (MIC=0.125-0.5mg/L) using RNA-Seq (RNA sequencing). RESULTS: Total RNA of 10 clinical isolates was used to make libraries and generated an average of 24.07Mb reads per sample; these were assembled into 1871 mRNA genes. Moreover, 21 differentially expressed genes (DEGs) were found between the N. gonorrhoeae isolates with susceptibility and decreased susceptibility to ceftriaxone with a fold change of ≥2 (P<0.05), among which 11 were upregulated and 10 were downregulated. Furthermore, all DEGs were verified by quantitative reverse transcription PCR (qRT-PCR), which detected 25 clinical isolates with decreased ceftriaxone susceptibility and 21 ceftriaxone-susceptible isolates. In addition, seven DEGs revealed relative expression levels by 2-ΔΔCt and showed a statistical significance (P≤0.05). Analysis of Gene Ontology (GO) terms and KEGG pathway for functional enrichment showed that six DEGs were related to the cellular component and one DEG was related to the biosynthesis of antibiotics, and these results might be related to ceftriaxone resistance. CONCLUSIONS: Examining ceftriaxone resistance-related genes in N. gonorrhoeae is necessary owing to the high morbidity and antimicrobial resistance of N. gonorrhoeae, especially its eventual resistance to third-generation extended-spectrum cephalosporins (cefixime and ceftriaxone). Moreover, this report provides a new direction for the study and control of ceftriaxone-resistant N. gonorrhoeae.


Subject(s)
Anti-Bacterial Agents/pharmacology , Ceftriaxone/pharmacology , Drug Resistance, Bacterial/genetics , Neisseria gonorrhoeae/genetics , Gene Expression , Gonorrhea/microbiology , Humans , Microbial Sensitivity Tests , Neisseria gonorrhoeae/drug effects , Polymerase Chain Reaction , RNA-Seq
14.
Diagn Microbiol Infect Dis ; 92(4): 325-331, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30292397

ABSTRACT

A microdilution method for the antibiotic susceptibility testing of Neisseria gonorrhoeae was established and improved, and the antibiotic resistance of N. gonorrhoeae samples isolated from 8 cities of Guangdong in 2016 was determined. The improved microdilution method was compared with the agar dilution method recommend by the World Health Organization (WHO) Western Pacific Region by testing the susceptibility of 100 clinical N. gonorrhoeae isolates. The essential agreement (EA), categorical agreement (CA), very major error (VME), major error (ME), and minor error (MIE) levels of the two methods were analyzed; the acceptable performance rates were measured as follows: ≥90% for EA or CA, ≤3% for VME or ME, and ≤7% for MIE. The EA, CA, VME, ME, and MIE of each method for 7 antibiotics, penicillin, tetracycline, ciprofloxacin, spectinomycin, ceftriaxone, cefixime, and azithromycin, were 96%-100%, 94%-100%, 0%-3%, 0%-2%, and 0%-6%, respectively. The Wilcoxon signed-rank test results indicated 94%-100% agreement between the 2 methods after excluding off-scale values (P > 0.05). The susceptibility of 634 N. gonorrhoeae strains to the 7 antibiotics above were tested through the microdilution method. The resistant rates of the isolates against ciprofloxacin, tetracycline, penicillin, and azithromycin were 99.8%, 88.3%, 53.8%, and 11%, and the percentages of the isolates with decreased susceptibility to ceftriaxone (minimum inhibitory concentration [MIC] ≥0.125 µg/mL) and cefixime (MIC ≥0.25 µg/mL) were 2.1% and 12%, respectively, in Guangdong. Among 8 cities, Shenzhen had the highest rates of resistance against penicillin (77.8%) and decreased susceptibility against ceftriaxone (5.6%). Zhuhai had the highest rates of decreased susceptibility against cefixime (30.1%), and Jiangmen had the highest azithromycin-resistant isolates (16.8%). The findings from this study indicated that the improved microdilution method is an alternative for testing the antimicrobial susceptibility of N. gonorrhoeae. The resistance rates of N. gonorrhoeae against penicillin, tetracycline, and ciprofloxacin were high. While ceftriaxone, cefixime, and spectinomycin remained effective against N. gonorrhoeae, their effectiveness seemed to be decreasing over time. Azithromycin therapy requires timely susceptibility test results.


Subject(s)
Anti-Bacterial Agents/pharmacology , Gonorrhea/microbiology , Microbial Sensitivity Tests , Neisseria gonorrhoeae/drug effects , Anti-Bacterial Agents/therapeutic use , China , Cities , Drug Resistance, Bacterial , Female , Gonorrhea/diagnosis , Gonorrhea/epidemiology , Humans , Male , Microbial Sensitivity Tests/methods , Neisseria gonorrhoeae/isolation & purification
15.
AMB Express ; 7(1): 48, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28233287

ABSTRACT

BACKGROUND AND OBJECTIVE: Gonorrhea is a sexually transmitted disease caused by the bacterium Neisseria gonorrhoeae. Rapid detection is crucial for effective prevention and treatment. This study developed and tested a low-cost effective method for detecting N. gonorrhoeae, especially in developing countries. METHODS: DNA from a N. gonorrhoeae standard strain, as well as from 26 genital secretion samples of gonorrhea patients, were isolated and used for loop-mediated isothermal amplification (LAMP) assay, which was conducted using either an automatic real-time PCR analyzer or a water bath. The amplified porA pseudogene sequence was compared with the NCBI database and the LAMP results were compared with that of the traditional culture method for its sensitivity and specificity. RESULTS: LAMP was able to detect Neisseria DNA at a concentration as low as 1 pg/µL (1 × 103 CFU/mL cells). The LAMP assay results obtained using an automatic real-time PCR analyzer was similar to that of the water bath. Relative to traditional culture, the sensitivity and specificity of the LAMP assay were 94.7 and 85.7%, respectively. CONCLUSION: LAMP was sensitive and reliable for detecting the porA gene of N. gonorrhoeae. It could be used as a rapid, low cost, and effective method for detecting N. gonorrhoeae.

16.
PLoS One ; 11(7): e0159658, 2016.
Article in English | MEDLINE | ID: mdl-27434536

ABSTRACT

BACKGROUND: Chlamydia trachomatis is one of the most prevalent bacterial sexually transmitted infection in China. Although C. trachomatis genotypes can be discriminated by outer membrane protein gene (ompA) sequencing, currently available methods have limited resolutions. This study used a high-resolution genotyping method, namely, multilocus variable number tandem-repeat analysis with ompA sequencing (MLVA)-ompA, to investigate the local epidemiology of C. trachomatis infections among men who have sex with men (MSM) and men who have sex with women (MSW) attending a sexually transmitted diseases (STD) clinic in Guangzhou, China. METHODS: Rectal specimens from MSM and urethral specimens from MSW were collected between January 2013 and July 2014 at the Guangdong Provincial Center STD clinic. The specimens were sent to the laboratory for analyses. All specimens that were tested positive for C. trachomatis by the commercial nucleic acid amplification tests were genotyped by MLVA-ompA. RESULTS: Fifty-one rectal specimens from MSM and 96 urethral specimens from MSW were identified with C. trachomatis. One hundred and forty-four of the 147 specimens were fully genotyped by MLVA-ompA. Rectal specimens from MSM were divided into four ompA genotypes and urethral specimens from MSW into nine genotypes. No mixed infections were found among all specimens. The most frequent genotypes were D, G, J, E and F. All specimens were further divided into 46 types after ompA genotyping was combined with MLVA. Genotypes D-8.7.1 and G-3.4a.3 were the most frequent among MSM, whereas genotypes D-3.4a.4, E-8.5.1, F-8.5.1, and J-3.4a.2 were the most frequent subtypes among MSW. The discriminatory index D was 0.90 for MLVA, 0.85 for ompA, and 0.95 for MLVA-ompA. CONCLUSIONS: The most prevalent MLVA-ompA genotypes were significantly different between MSM and MSW from Guangzhou, China. Moreover, MLVA-ompA represented a more favorable degree of discrimination than ompA and could be a reliable complement for ompA for the routine subtypes of C. trachomatis.


Subject(s)
Bacterial Outer Membrane Proteins/genetics , Chlamydia Infections/epidemiology , Chlamydia trachomatis/genetics , Genotype , Homosexuality, Male , Sexual Partners , Adolescent , Adult , China/epidemiology , Chlamydia Infections/diagnosis , Chlamydia Infections/microbiology , Chlamydia trachomatis/classification , Chlamydia trachomatis/isolation & purification , Female , Gene Expression , Humans , Male , Middle Aged , Multilocus Sequence Typing , Phylogeny , Rectum/microbiology , Tandem Repeat Sequences , Urethra/microbiology
17.
BMC Infect Dis ; 15: 412, 2015 Oct 09.
Article in English | MEDLINE | ID: mdl-26453557

ABSTRACT

BACKGROUND: Gonococcal antimicrobial resistance is a global problem. Different resistance plasmids have emerged and spread among the isolates of Neisseria gonorrhoeae worldwide and in China. We conducted this study to monitor the plasmid-mediated penicillin and tetracycline resistance among N. gonorrhoeae isolates in Guangzhou from 2002 to 2012. METHODS: Consecutive isolates of N. gonorrhoeae were collected from outpatients with gonorrhea attending the STD clinic in Guangdong Provincial Centre for Skin Diseases and STIs Control and Prevention. Penicillinase-producing N. gonorrhoeae (PPNG) isolates were analyzed by the paper acidometric method. Plasmid-mediated resistance to tetracycline in N. gonorrhoeae (TRNG) isolates was screened by the agar plate dilution method. Plasmid types were determined for TRNG and PPNG isolates using polymerase chain reaction (PCR). Minimum inhibitory concentrations (MICs) to penicillin and tetracycline were detected by the agar plate dilution. RESULTS: Of 1378 consecutive N. gonorrhoeae isolates, 429 PPNG and 639 TRNG isolates were identified. The prevalence of PPNG, TRNG, and PPNG/TRNG increased from 18.3 to 47.1 % (χ (2) = 31.57, p < 0.001), from 29.4 to 52.1 % (χ (2) = 16.28, p < 0.001) and from 10.0 to 26.2 % (χ (2) = 10.46, p < 0.001) between 2002 and 2012, respectively. Genotyping of plasmids among PPNGs showed that the majority (93.7 %) of the isolates were the Asian type plasmids, while the African type plasmid emerged in 2008 and rapidly increased to 14.0 % in 2012 (χ (2) = 25.03, p < 0.001). For TRNGs, all 639 isolates carried the Dutch type plasmid. MICs of penicillin G and tetracycline persisted at high levels and the MIC90s were 32-fold higher than the resistant cutoff point over 11 years. The prevalence rates of penicillin- and tetracycline-resistant N. gonorrhoeae varied from 90.9 to 91.1 % and from 88.3 to 89.3 % during 2002 to 2012, respectively. CONCLUSIONS: Resistance to penicillin and tetracycline among N. gonorrhoeae isolates remained at high levels in Guangzhou. The Asian type PPNG continued to spread and Dutch type TRNG was still the dominant strain. The African type PPNG has emerged and is spreading rapidly.


Subject(s)
Drug Resistance, Bacterial/genetics , Gonorrhea/epidemiology , Gonorrhea/microbiology , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/genetics , Penicillins/pharmacology , Anti-Bacterial Agents/pharmacology , China/epidemiology , Gonorrhea/drug therapy , Humans , Microbial Sensitivity Tests , Neisseria gonorrhoeae/isolation & purification , Penicillin G , Penicillinase/genetics , Penicillinase/metabolism , Plasmids , Polymerase Chain Reaction , Tetracycline Resistance/genetics , beta-Lactamases/genetics
18.
Jpn J Infect Dis ; 67(4): 288-91, 2014.
Article in English | MEDLINE | ID: mdl-25056075

ABSTRACT

Antibiotic susceptibility of Neisseria gonorrhoeae in Guangzhou during 2002-2011 showed that resistance to penicillin and ciprofloxacin was high, while ceftriaxone remained effective although there was a trend towards reduced sensitivity.


Subject(s)
Anti-Bacterial Agents/pharmacology , Gonorrhea/microbiology , Neisseria gonorrhoeae/drug effects , Chi-Square Distribution , China/epidemiology , Cohort Studies , Drug Resistance, Bacterial , Gonorrhea/epidemiology , Humans , Microbial Sensitivity Tests
19.
Int J Radiat Oncol Biol Phys ; 88(4): 955-60, 2014 Mar 15.
Article in English | MEDLINE | ID: mdl-24606854

ABSTRACT

PURPOSE: Ataxia telangiectasia mutated (ATM) protein is important in the DNA damage response because it repairs radiation-induced damage in cancers. We examined the effect of microRNA-223 (miR-223), a regulator of ATM expression, on radiation sensitivity of cancer cells. METHODS AND MATERIALS: Human embryonic kidney 293 T (293T) cells were infected with pLL3.7-miR-223 plasmid to generate the pLL3.7-miR-223 and -empty virus (EV) lentivirus (miR-223 and EV). A dual luciferase assay in which the reporter contained wild-type 3' untranslated region (UTR) of ATM was performed. U87MG cells were infected with miR-223 or EV to establish the overexpressed stable cell lines (U87-223 or U87-EV, respectively). Cells were irradiated in vitro, and dose enhancement ratios at 2 Gy (DER2) were calculated. Hind legs of BALB/c athymic mice were injected with U87-223 or U87-EV cells; after 2 weeks, half of the tumors were irradiated. Tumor volumes were tracked for a total of 5 weeks. RESULTS: The dual luciferase reporter assay showed a significant reduction in luciferase activity of 293T cells cotransfected with miR-223 and the ATM 3'UTR compared to that in EV control. Overexpression of miR-223 in U87MG cells showed that ATM expression was significantly downregulated in the U87-223 cells compared to that in U87-EV (ATM/ß-actin mRNA 1.0 vs 1.5, P<.05). U87-223 cells were hypersensitive to radiation compared to U87-EV cells in vitro (DER2 = 1.32, P<.01). Mice injected with miR-223-expressing tumors had almost the same tumors after 3 weeks (1.5 cm(3) vs 1.7 cm(3)). However, irradiation significantly decreased tumor size in miR-223-expressing tumors compared to those in controls (0.033 cm(3) vs 0.829 cm(3)). CONCLUSIONS: miR-223 overexpression downregulates ATM expression and sensitizes U87 cells to radiation in vitro and in vivo. MicroRNA-223 may be a novel cancer-targeting therapy, although its cancer- and patient-specific roles are currently undefined.


Subject(s)
Ataxia Telangiectasia Mutated Proteins/metabolism , MicroRNAs/physiology , Radiation Tolerance/physiology , Animals , Cell Line, Tumor , Down Syndrome , Genes, Reporter , Heterografts , Humans , Luciferases/metabolism , Mice , Mice, Inbred BALB C , Mice, Nude
20.
Mol Oncol ; 8(2): 366-77, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24388360

ABSTRACT

In our previous study, we identified 1241 loci with somatic copy number alterations in human hepatocellular carcinoma (HCC) using Affymetrix SNP 6.0 arrays, and a putative cancer gene SERPINA5 was uncovered in a novel chromosomal region with recurrent copy number loss at 14q31.1-32.13. The SERPINA5 was reported to be deregulated in renal, breast, prostate and ovarian cancers. However, the roles of SERPINA5 in cancer remain greatly elusive. In this study, we found that the DNA dosage and expression level of the SERPINA5 gene were significantly decreased in HCC by quantitative real-time PCR. Notably, the expression levels of SERPINA5 negatively correlated with malignant progression of HCC. The SERPINA5 gene was further observed to reduce in vitro and in vivo metastatic potential of HCC cells. Moreover, secreted SERPINA5 protein also could inhibit the metastatic ability of HCC cells. Finally, we discovered that one of the mechanisms explaining SERPINA5 inhibition of HCC metastasis is through direct interaction with fibronectin and disruption of the fibronectin-integrin signaling pathway. These findings highlight an important role of SERPINA5 in the regulation of migratory and metastatic potentials of HCC and suggest a potential application of SERPINA5 in cancer treatment.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Integrin beta1/metabolism , Liver Neoplasms/metabolism , Neoplasm Proteins/metabolism , Protein C Inhibitor/metabolism , Signal Transduction , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Fibronectins/genetics , Fibronectins/metabolism , Gene Expression Regulation, Neoplastic/genetics , Humans , Integrin beta1/genetics , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Neoplasm Proteins/genetics , Protein C Inhibitor/genetics
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