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1.
Phys Rev Lett ; 132(2): 027201, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38277594

RESUMO

We developed an exact theory of the superregular breathers (SRBs) of Manakov equations. We have shown that the vector SRBs do exist both in the cases of focusing and defocusing Manakov systems. The theory is based on the eigenvalue analysis and on finding the exact links between the SRBs and modulation instability. We have shown that in the focusing case the localized periodic initial modulation of the plane wave may excite both a single SRB and the second-order SRBs involving four fundamental breathers.

2.
Antimicrob Agents Chemother ; 66(5): e0025122, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35465683

RESUMO

The continued emergence of Neisseria gonorrhoeae isolates which are resistant to first-line antibiotics has reinvigorated interest in alternative therapies such as expanded use of gentamicin (Gen). We hypothesized that expanded use of Gen promotes emergence of gonococci with clinical resistance to this aminoglycoside. To understand how decreased susceptibility of gonococci to Gen might develop, we selected spontaneous low-level Gen-resistant (GenR) mutants (Gen MIC = 32 µg/mL) of the Gen-susceptible strain FA19. Consequently, we identified a novel missense mutation in fusA, which encodes elongation factor G (EF-G), causing an alanine (A) to valine (V) substitution at amino acid position 563 in domain IV of EF-G; the mutant allele was termed fusA2. Transformation analysis showed that fusA2 could increase the Gen MIC by 4-fold. While possession of fusA2 did not impair either in vitro gonococcal growth or protein synthesis, it did result in a fitness defect during experimental infection of the lower genital tract in female mice. Through bioinformatic analysis of whole-genome sequences of 10,634 international gonococcal clinical isolates, other fusA alleles were frequently detected, but genetic studies revealed that they could not decrease Gen susceptibility in a similar manner to fusA2. In contrast to these diverse international fusA alleles, the fusA2-encoded A563V substitution was detected in only a single gonococcal clinical isolate. We hypothesize that the rare occurrence of fusA2 in N. gonorrhoeae clinical isolates is likely due to a fitness cost during infection, but compensatory mutations which alleviate this fitness cost could emerge and promote GenR in global strains.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Substituição de Aminoácidos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Feminino , Gentamicinas/farmacologia , Gentamicinas/uso terapêutico , Gonorreia/tratamento farmacológico , Camundongos , Testes de Sensibilidade Microbiana , Fator G para Elongação de Peptídeos
3.
Neural Plast ; 2022: 6472475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915650

RESUMO

Low-intensity focused ultrasound (LIFU) is a potential noninvasive method to alleviate allodynia by modulating the central nervous system. However, the underlying analgesic mechanisms remain unexplored. Here, we assessed how LIFU at the anterior cingulate cortex (ACC) affects behavior response and central plasticity resulting from chronic constrictive injury (CCI). The safety of LIFU stimulation was assessed by hematoxylin and eosin (H&E) and Fluoro-Jade C (FJC) staining. A 21-day ultrasound exposure therapy was conducted from day 91 after CCI surgery in mice. We assessed the 50% mechanical withdrawal threshold (MWT50) using Von Frey filaments (VFFs). The expression levels of microtubule-associated protein 2 (MAP2), growth-associated protein 43 (GAP43), and tau were determined via western blotting (WB) and immunofluorescence (IF) staining to evaluate the central plasticity in ACC. The regions of ACC were activated effectively and safely by LIFU stimulation, which significantly increased the number of c-fos-positive cells (P < 0.05) with no bleeding, coagulative necrosis, and neuronal loss. Under chronic neuropathic pain- (CNP-) induced allodynia, MWT50 decreased significantly (P < 0.05), and overexpression of MAP2, GAP43, and tau was also observed. After 3 weeks of treatment, significant increases in MWT50 were found in the CCI+LIFU group compared with the CCI group (P < 0.05). WB and IF staining both demonstrated a significant reduction in the expression levels of MAP2, GAP43, and tau (P < 0.05). LIFU treatment on ACC can effectively attenuate CNP-evoked mechanical sensitivity to pain and reverse aberrant central plasticity.


Assuntos
Hiperalgesia , Neuralgia , Animais , Giro do Cíngulo/metabolismo , Hiperalgesia/metabolismo , Hiperalgesia/terapia , Camundongos , Neuralgia/metabolismo , Neuralgia/terapia , Plasticidade Neuronal , Ratos , Ratos Sprague-Dawley
4.
Phys Rev Lett ; 127(9): 094102, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34506207

RESUMO

Nonlinear waves become asymmetric when asymmetric physical effects are present within the system. One example is the self-steepening effect. When exactly balanced with dispersion, it leads to a fully integrable system governed by the Chen-Lee-Liu equation. The latter provides a natural basis for the analysis of asymmetric wave dynamics just as nonlinear Schrödinger or Korteweg-de Vries equations provide the basis for analyzing solitons with symmetric profile. In this work, we found periodic wave trains of the Chen-Lee-Liu equation evolved from fully developed modulation instability and analyzed a highly nontrivial spectral evolution of such waves in analytic form that shows strong asymmetry of its components. We present the conceptual basis for finding such spectra that can be used in analyzing asymmetric nonlinear waves in other systems.

5.
J Formos Med Assoc ; 120(4): 1090-1099, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33183879

RESUMO

BACKGROUND/PURPOSE: The evidence provided by syntheses of the preventative effects of gabexate mesilate against pancreatitis among patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) is limited and highly heterogeneous. To enhance the understanding of this topic, this study aimed to provide overview of gabexate mesilate on preventing post ERCP pancreatitis (PEP) by synthesizing all relevant randomized controlled trials (RCTs). METHODS: We searched three databases for relevant RCTs. Two authors independently extracted data of pancreatitis incidence after ERCP, abdominal pain within 48 hours, and hyperamylasemia for quality assessment and meta-analysis. RESULTS: Thirteen RCTs with 3718 patients undergoing ERCP met the eligibility criteria and were included. The results revealed that the use of gabexate mesilate led to lower PEP (Peto odds ratio: 0.66, 95% confidence interval [CI]: 0.49 to 0.89), especially in the subgroup of gabexate mesilate infusion starting more than 30 min (Risk ratio: 0.45, 95% CI: 0.29 to 0.72). CONCLUSION: The present synthesis found that gabexate mesilate could be an option of prophylactic treatment of pancreatitis for patients undergoing ERCP, and reveals that it is favorable to administer it starting 30 min before the ERCP. This evidence may improve the clinical prevention of PEP.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Gabexato , Pancreatite , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Gabexato/uso terapêutico , Humanos , Pancreatite/etiologia , Pancreatite/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Somatostatina
6.
J Craniofac Surg ; 32(3): 878-882, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038187

RESUMO

BACKGROUND: Advances in the understanding of wrinkling crow's feet while improving the safety and efficacy of botulinum toxin type A injection has pointed to drug dispersion in the lateral orbital wrinkles as a cause of adverse events of botulinum toxin type A injection. The purpose of this study is to identify the distribution of temporal and zygomatic branches of facial nerve in the orbicularis oculi muscles. METHODS: Anatomical dissection of cadavers was performed in 31 cadavers, 13 females and 18 males, with ages ranging from 20 to 60 years, which of all had been embalmed by 10% formalin solution. The facial nerve was identified within subcutaneous tissue close periorbital region and both traced proximal and distal. Its temporal branch, zygomatic branch, facial and muscular entrance were located and accurately measured relative to established surface landmarks. RESULTS: Dissection of the facial nerve revealed 2 to 6 entrances of the temporal branch into the orbicularis oculi and 1 to 5 entrances of the zygomatic branch into the orbicularis oculi. Concerning the measurements of neural entering points, distance and angle from orbicularis oculi muscle to lateral ocular angle, a distribution map of its muscular entrance and their patterns of distribution were constructed. According to the dense area of the coordinate map, there were 3 points determined as the muscular entrance points to established surface landmarks. CONCLUSIONS: An anatomical dissection of cadavers was performed to identify the distribution of temporal and zygomatic branches of the facial nerve in the orbicularis oculi. According to the dense area of the coordinate map, the surface landmarks of 3 points were established as the muscular entrance of the facial nerve (MEF).


Assuntos
Nervo Facial , Envelhecimento da Pele , Adulto , Cadáver , Pálpebras , Face , Músculos Faciais , Nervo Facial/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
J Antimicrob Chemother ; 75(9): 2499-2502, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32473014

RESUMO

BACKGROUND: Ceftriaxone resistance in Neisseria gonorrhoeae has become an imminent threat to effective control of gonorrhoea globally. In recent years, the ceftriaxone-resistant FC428 clone has shown international dissemination. After our first report of the FC428 clone in China in 2016, we now describe another six cases of FC428-related ceftriaxone-resistant N. gonorrhoeae isolates from 2017 and 2018. OBJECTIVES: To identify the phenotypic and molecular characteristics of newly reported ceftriaxone-resistant isolates in China and to investigate the relationship between these isolates and FC428 clones reported globally. METHODS: Antimicrobial susceptibility to ceftriaxone, cefixime, azithromycin, spectinomycin, penicillin, ciprofloxacin and tetracycline was determined by the agar dilution method. N. gonorrhoeae multi-antigen sequence typing (NG-MAST), MLST and N. gonorrhoeae sequence typing for antimicrobial resistance (NG-STAR) were performed for genotyping and SNPs extracted from whole-genome sequences were used for phylogenetic analysis. RESULTS: All isolates were resistant to ceftriaxone, cefixime, penicillin, tetracycline and ciprofloxacin, but were susceptible to azithromycin and spectinomycin. NG-MAST, MLST and NG-STAR genotyping showed that all isolates shared identical or similar STs (<10 bp difference) to FC428 (NG-MAST ST3435, MLST ST1903, NG-STAR ST233) and contained the same mosaic penA allele 60.001. Phylogenetic analysis showed the Chinese isolates spreading in the whole phylogenetic tree and fully mixed with other international isolates. Half of the Chinese isolates were more closely related (<100 SNPs) to Japanese isolates than other international isolates. CONCLUSIONS: The newly reported cases in China were related to the internationally spreading FC428 clone. These isolates might have played a central role in international transmission of the FC428 clone. High ceftriaxone doses (1-2 g) still provide effective therapy.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ceftriaxona/farmacologia , China/epidemiologia , Células Clonais , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/genética , Filogenia
8.
Emerg Infect Dis ; 25(7): 1427-1429, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30900979

RESUMO

In 2016, we identified a ceftriaxone-resistant Neisseria gonorrhoeae isolate in China. The strain genotype was identical to the resistant clone FC428 that originated in Japan. Enhanced international collaborative surveillance programs are crucial to track the transmission of the ceftriaxone-resistant clones.


Assuntos
Antibacterianos/farmacologia , Ceftriaxona/farmacologia , Farmacorresistência Bacteriana , Gonorreia/epidemiologia , Gonorreia/microbiologia , Neisseria gonorrhoeae/efeitos dos fármacos , China/epidemiologia , Resistencia a Medicamentos Antineoplásicos , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/genética
9.
Emerg Infect Dis ; 24(4): 804-806, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29553336

RESUMO

Cephalosporin-resistant Neisseria gonorrhoeae is a major public health concern. N. gonorrhoeae of multiantigen sequence type G1407 and multilocus sequence type 1901 is an internationally spreading cephalosporin-resistant clone. We detected 4 cases of infection with this clone in China and analyzed resistance determinants by using N. gonorrhoeae sequence typing for antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Farmacorresistência Bacteriana , Gonorreia/epidemiologia , Gonorreia/microbiologia , Neisseria gonorrhoeae/efeitos dos fármacos , China/epidemiologia , Genes Bacterianos , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/genética
10.
PLoS Med ; 15(2): e1002499, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29408881

RESUMO

BACKGROUND: Gonorrhea remains one of the most common sexually transmitted diseases worldwide. Successful treatment has been hampered by emerging resistance to each of the antibiotics recommended as first-line therapies. We retrospectively analyzed the susceptibility of gonorrhea to azithromycin and ceftriaxone using data from the China Gonococcal Resistance Surveillance Programme (China-GRSP) in order to provide evidence for updating the treatment recommendations in China. METHODS AND FINDINGS: In this study, we included 3,849 isolates collected from patients with a confirmed positive Neisseria gonorrhoeae (N. gonorrhoeae) culture at clinic visits during the period of 1 January 2013 through 31 December 2016 in 7 provinces. Antimicrobial susceptibility testing of gonorrhea isolates using agar dilution was conducted to determine minimum inhibitory concentration (MIC). Resistance to azithromycin (RTA) was defined as MIC ≥ 1.0 mg/l, and decreased susceptibility to ceftriaxone (DSC) was defined as MIC ≥ 0.125 mg/l. The prevalence of isolates with RTA was 18.6% (710/3,827; 95% CI 17.4%-19.8%). The percentage of patients with DSC fluctuated between 9.7% and 12.2% over this period. The overall prevalence of isolates with both RTA and DSC was 2.3% (87/3,827; 95% CI 1.9%-2.8%) and it increased from 1.9% in 2013 to 3.3% in 2016 (chi-squared test for trend, P = 0.03). Study limitations include the retrospective study design and potential biases in the sample, which may overrepresent men with symptomatic infection, coastal residents, and people reporting as heterosexual. CONCLUSIONS: To our knowledge, this is the first national study on susceptibility of N. gonorrhoeae to azithromycin and ceftriaxone in China. Our findings indicate high rates of RTA and DSC from 2013 to 2016. Although dual therapy with azithromycin and ceftriaxone has been recommended by WHO and many countries to treat gonorrhea, reevaluation of this therapy is needed prior to its introduction in China.


Assuntos
Azitromicina/uso terapêutico , Ceftriaxona/uso terapêutico , Farmacorresistência Bacteriana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Neisseria gonorrhoeae/efeitos dos fármacos , Adulto , Antibacterianos/uso terapêutico , China/epidemiologia , Monitoramento Epidemiológico , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/patogenicidade , Prevalência , Estudos Retrospectivos
11.
Sex Transm Dis ; 44(4): 197-201, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28282644

RESUMO

OBJECTIVE: This study aimed to gain information on the antimicrobial susceptibility and molecular epidemiological typing of Neisseria gonorrhoeae (NG) isolates in China in 2012. METHODS: A total of 244 NG isolates were consecutively recovered from patients with uncomplicated gonorrhea attending sexually transmitted disease clinics in 3 Chinese cities-Guangzhou, Nanjing, and Tianjin-in 2012. Neisseria gonorrhoeae susceptibilities to penicillin and tetracycline were examined by detecting penicillinase-producing NG (PPNG) and high-level tetracycline-resistant NG, and NG susceptibilities to ciprofloxacin, spectinomycin, ceftriaxone, and cefixime were determined using an agar dilution method. Neisseria gonorrhoeae isolates were typed by multiple-locus variable number tandem repeat analysis. We conducted a χ analysis to compare clusters with Bonferroni correction and Kruskal-Wallis test. RESULTS: Neisseria gonorrhoeae isolates gathered from the 3 cities differed significantly in the prevalence of tetracycline-resistant NG (P < 0.001) and NG treated with ceftriaxone with a minimum inhibitory concentration of 0.125 mg/L or higher (P < 0.001). The analysis of the combination of the 7 variable number of tandem repeats loci for all of the 244 isolates yielded 110 multiple-locus variable number tandem repeat analysis types falling into 5 clusters. Cluster III was associated with PPNG, whereas cluster II was associated with non-PPNG (P < 0.05) and NG treated with ceftriaxone with a minimum inhibitory concentration of 0.125 mg/L or higher (P < 0.05). CONCLUSIONS: Antimicrobials that can be used with confidence to treat NG infection currently in China include ceftriaxone and spectinomycin, but not penicillin, tetracycline, ciprofloxacin, and cefixime. Moreover, some of the resulting clusters were associated with PPNG and NG with decreased ceftriaxone susceptibility.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Gonorreia/tratamento farmacológico , Gonorreia/microbiologia , Neisseria gonorrhoeae/efeitos dos fármacos , Adulto , Cefixima/farmacologia , Ceftriaxona/farmacologia , Colo do Útero/microbiologia , Distribuição de Qui-Quadrado , China/epidemiologia , Ciprofloxacina/farmacologia , Feminino , Gonorreia/epidemiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Repetições Minissatélites , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Penicilinas/farmacologia , Prevalência , Espectinomicina/farmacologia , Tetraciclina/farmacologia , Uretra/microbiologia , Adulto Jovem
12.
J Antimicrob Chemother ; 71(1): 92-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26472770

RESUMO

OBJECTIVES: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major public health concern worldwide. This is the first nationwide study, performed within the China Gonococcal Antimicrobial Susceptibility Programme (China-GASP), regarding AMR, including ceftriaxone genetic resistance determinants, and molecular epidemiology of gonococci in China. METHODS: Gonococcal isolates (n = 1257) from consecutive patients were collected at 11 sentinel sites distributed across China during 2012-13. Susceptibility to ceftriaxone, spectinomycin, ciprofloxacin and tetracycline was determined using the agar dilution method. Ceftriaxone resistance determinants penA and penB were examined using sequencing. N. gonorrhoeae multiantigen sequence typing (NG-MAST) was performed for molecular epidemiology. RESULTS: Among isolates, 0.2% were resistant to spectinomycin, 4.4% to ceftriaxone, 42.9% to tetracyclines (high-level resistance) and 99.8% to ciprofloxacin. Among 890 sequenced isolates, 16 (1.8%) possessed a penA mosaic allele; 4 of these isolates belonged to the MDR internationally spread NG-MAST genogroup G1407 (first description in China). Non-mosaic penA alleles with an A501T mutation and an A102D alteration in porB1b were statistically associated with decreased susceptibility/resistance to ceftriaxone. NG-MAST G10339, G1424 and G1053 were associated with decreased susceptibility/resistance to ceftriaxone. CONCLUSIONS: In China, ceftriaxone and spectinomycin can continue to be recommended for gonorrhoea treatment, with the possible exception of Hainan and Sichuan provinces where ceftriaxone resistance exceeded 5% and AMR surveillance needs to be strengthened. Molecular approaches including genotyping and AMR determinant analysis can be valuable to supplement and enhance conventional surveillance of gonococcal AMR in China.


Assuntos
Antibacterianos/farmacologia , Ceftriaxona/farmacologia , Gonorreia/epidemiologia , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/efeitos dos fármacos , Resistência beta-Lactâmica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Genes Bacterianos , Genótipo , Gonorreia/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Análise de Sequência de DNA , Adulto Jovem
13.
J Antimicrob Chemother ; 69(11): 2959-65, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25011655

RESUMO

OBJECTIVES: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major problem worldwide. This study investigated the AMR, genetic ceftriaxone resistance determinants and molecular epidemiology of N. gonorrhoeae in Nanjing, China. METHODS: N. gonorrhoeae isolates were collected in 2007 (n = 198) and 2012 (n = 80). The susceptibility to ceftriaxone, spectinomycin, ciprofloxacin and tetracycline was determined using an agar-dilution method. The ceftriaxone resistance determinants penA, mtrR and penB were examined using sequencing. N. gonorrhoeae multi-antigen sequence typing (NG-MAST) was performed for molecular epidemiology. RESULTS: All isolates were resistant to ciprofloxacin, 42.4% produced ß-lactamase and 34.9% showed high-level resistance to tetracycline (MIC ≥16 mg/L). In total, 5.4% of isolates were resistant to ceftriaxone; however, all of these isolates were obtained in 2007 and the susceptibility to ceftriaxone appeared to have increased. All isolates were susceptible to spectinomycin. No penA mosaic alleles were found. Non-mosaic penA alleles with A501T and G542S alterations, an H105Y alteration in mtrR and an A102D/N alteration in porB1b were statistically associated with decreased susceptibility or resistance to ceftriaxone. The most prevalent NG-MAST sequence types (STs) were ST568 (n = 13), ST270 (n = 9) and ST421 (n = 7). ST270 was the most common ST in isolates with decreased susceptibility or resistance to ceftriaxone. CONCLUSIONS: Ceftriaxone, ideally 500 mg and together with azithromycin (1-2 g), should be recommended for treatment of gonorrhoea in Nanjing, China. However, N. gonorrhoeae strains with resistance to ceftriaxone have been found in Nanjing. NG-MAST and ceftriaxone resistance determinant analysis can be valuable to supplement the antimicrobial resistance surveillance in China, which needs to be further strengthened.


Assuntos
Antibacterianos/farmacologia , Ceftriaxona/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Infecciosos/farmacologia , China/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Adulto Jovem
14.
BMC Infect Dis ; 14: 454, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25149062

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major concern worldwide. It has been recently feared that the blaTEM-1 gene is, via blaTEM-135, evolving into an extended-spectrum ß-lactamase (ESBL), which could degrade all cephalosporins including ceftriaxone. The aims of the present study were to characterize the blaTEM genes, types of ß-lactamase plasmids, the degradation of ampicillin by TEM-135 compared to TEM-1, and to perform molecular epidemiological typing of ß-lactamase-producing N. gonorrhoeae strains internationally. METHODS: ß-lactamase producing N. gonorrhoeae isolates (n = 139) cultured from 2000 to 2011 in 15 countries were examined using antibiograms, blaTEM gene sequencing, ß-lactamase plasmid typing, and N. gonorrhoeae multiantigen sequence typing (NG-MAST). Furthermore, the blaTEM gene was sequenced in the first described Toronto plasmid (pJD7), one of the first Asian plasmids (pJD4) and African plasmids (pJD5) isolated in Canada. The degradation of ampicillin by TEM-135 compared to TEM-1 was examined using a MALDI-TOF MS hydrolysis assay. RESULTS: Six different blaTEM sequences were identified (among isolates with 125 different NG-MAST STs), i.e. blaTEM-1 (in 104 isolates), blaTEM-135 (in 30 isolates), and four novel blaTEM sequences (in 5 isolates). The blaTEM-1 allele was only found in the African and Asian plasmids, while all Rio/Toronto plasmids possessed the blaTEM-135 allele. Most interesting, the first described gonococcal Toronto plasmid (pJD7), identified in 1984, also possessed the highly conserved blaTEM-135 allele. The degradation of ampicillin by TEM-135 compared to TEM-1 was indistinguishable in the MALDI-TOF MS hydrolysis assay. CONCLUSIONS: blaTEM-135, encoding TEM-135, is predominantly and originally associated with the Rio/Toronto plasmid and prevalent among the ß-lactamase producing gonococcal strains circulating globally. blaTEM-135 does not appear, as previously hypothesized, to have recently evolved due to some evolutionary selective pressure, for example, by the extensive use of extended-spectrum cephalosporins worldwide. On the contrary, the present study shows that blaTEM-135 existed in the Toronto plasmid from its discovery and that blaTEM-135 is highly conserved (not further evolved in the past >30 years). Nevertheless, international studies for monitoring the presence of different blaTEM alleles, the possible evolution of the blaTEM-135 allele, and the types of ß-lactamase producing plasmids, remain imperative.


Assuntos
Farmacorresistência Bacteriana , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Plasmídeos/genética , beta-Lactamases/genética , Ceftriaxona/farmacologia , Cefalosporinas/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem Molecular , Neisseria gonorrhoeae/efeitos dos fármacos , Prevalência
15.
Clin Infect Dis ; 56(5): 659-65, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23132172

RESUMO

BACKGROUND: Rapid point-of-care (POC) syphilis tests based on simultaneous detection of treponemal and nontreponemal antibodies (dual POC tests) offer the opportunity to increase coverage of syphilis screening and treatment. This study aimed to conduct a multisite performance evaluation of a dual POC syphilis test in China. METHODS: Participants were recruited from patients at sexually transmitted infection clinics and high-risk groups in outreach settings in 6 sites in China. Three kinds of specimens (whole blood [WB], fingerprick blood [FB], and blood plasma [BP]) were used for evaluating sensitivity and specificity of the Dual Path Platform (DPP) Syphilis Screen and Confirm test using its treponemal and nontreponemal lines to compare Treponema pallidum particle agglutination (TPPA) assay and toluidine red unheated serum test (TRUST) as reference standards. RESULTS: A total of 3134 specimens (WB 1323, FB 488, and BP 1323) from 1323 individuals were collected. The sensitivities as compared with TPPA were 96.7% for WB, 96.4% for FB, and 94.6% for BP, and the specificities were 99.3%, 99.1%, and 99.6%, respectively. The sensitivities as compared with TRUST were 87.2% for WB, 85.8% for FB, and 88.4% for BP, and the specificities were 94.4%, 96.1%, and 95.0%, respectively. For specimens with a TRUST titer of 1:4 or higher, the sensitivities were 100.0% for WB, 97.8% for FB, and 99.6% for BP. CONCLUSIONS: DPP test shows good sensitivity and specificity in detecting treponemal and nontreponemal antibodies in 3 kinds of specimens. It is hoped that this assay can be considered as an alternative in the diagnosis of syphilis, particularly in resource-limited areas.


Assuntos
Anticorpos Antibacterianos/sangue , Sistemas Automatizados de Assistência Junto ao Leito , Sorodiagnóstico da Sífilis/métodos , Sífilis/diagnóstico , Treponema pallidum/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Aglutinação , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Sífilis/imunologia , Adulto Jovem
16.
Sex Transm Dis ; 40(11): 872-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24113411

RESUMO

BACKGROUND: This study aimed to investigate the prevalence of penicillinase-producing Neisseria gonorrhoeae (PPNG) and their blaTEM-135 gene variant in 2007 and 2012 in Nanjing, China. In addition, molecular epidemiological typing of all isolates was performed to elucidate the genetic relationships of the PPNG strains. METHODS: A total of 199 and 77 N. gonorrhoeae isolates were collected at the National Center for STD Control in 2007 and 2012, respectively. Nitrocefin tests were performed to identify PPNG. Mismatch amplification mutation assay was used to identify blaTEM-135. All isolates were genotyped using N. gonorrhoeae multiantigen sequence typing (NG-MAST), and additionally, porB-based phylogenetic analysis was performed for the PPNG isolates. RESULTS: The total prevalence of PPNG isolates was 41% (114/276) and 58% (66/114) of these PPNG isolates possessed bla(TEM-135). In 2007, 45% (90/199) produced ß-lactamase, and of those PPNG, 58% (52/90) possessed bla(TEM-135). In 2012, 31% (24/77) were PPNG, and 58% (14/24) of those isolates contained bla(TEM-135). There were 162 NG-MAST STs among the 276 isolates, and 89 of those were novel STs. A strong association between specific NG-MAST STs and bla(TEM-135) was found, and the porB-based phylogenetic analysis showed a distant evolutionary relationship between isolates in 2007 and isolates in 2012. CONCLUSIONS: A high prevalence of PPNG and blaTEM-135 was found in Nanjing, China. bla(TEM-135) might be a precursor in the evolution into an extended-spectrum ß-lactamase that can degrade ceftriaxone, which stresses the need to continuously monitor PPNG, blaTEM-135, and additional evolving blaTEM gene variants.


Assuntos
Gonorreia/epidemiologia , Neisseria gonorrhoeae/isolamento & purificação , Penicilinase/farmacologia , China/epidemiologia , Resistência Microbiana a Medicamentos/genética , Feminino , Variação Genética , Gonorreia/genética , Gonorreia/microbiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Tipagem Molecular , Neisseria gonorrhoeae/genética , Filogenia , Vigilância da População , Sorotipagem
17.
Infect Drug Resist ; 16: 1441-1448, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36942021

RESUMO

Objective: This study aimed to assess the drug susceptibility of clinical isolates of Neisseria gonorrhoeae to spectinomycin, ceftriaxone and azithromycin. Moreover, the temporal trends in the minimum inhibitory concentration (MIC) of five antibiotics from Zhejiang, China, are also in the scope of this study. Methods: A total of 1710 gonococcal clinical strains were collected between 2007 and 2021 from health-care institutions in Zhejiang. The MICs of ceftriaxone, azithromycin, spectinomycin, penicillin and ciprofloxacin were assessed by agar dilution method on 1710 Neisseria gonorrhoeae isolates. Count data were expressed as strains and rates, and MICs distribution was elucidated using descriptive statistics. Results: The total resistance rates of gonococci to azithromycin, spectinomycin, penicillin and ciprofloxacin in this study were 19.3%, 0.3%, 75.4% and 99.7%, respectively. Conclusion: The in vitro results showed a high prevalence of resistance to ciprofloxacin and penicillin. Azithromycin resistance rate has exceeded 5%, suggested a high prevalence of resistance. Ceftriaxone and spectinomycin are suggested based on this study for the treatment of Neisseria gonorrhoeae in Zhejiang.

18.
Sex Transm Dis ; 39(5): 354-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22504598

RESUMO

OBJECTIVES: To determine the prevalence and risk factors of herpes simplex virus type 2 (HSV-2) infection and its coinfection with human immunodeficiency virus (HIV) in men who have sex with men (MSM) in China. METHODS: A convenience sample of 1462 MSM were recruited from different settings (an STD clinic, a health center, and MSM venues) in 3 cities in China. Blood specimens were collected for testing for antibodies to HSV-2 and HIV to determinate the seroprevalence of HSV-2 infection and HSV-2/HIV coinfection. Information on sociodemographic and behavioral characteristics was collected to determine the risk factors associated with the infections. RESULTS: The prevalence of HSV-2 infection in 1462 MSM was 16.0% (95% confidence interval [CI], 14.2%-18.0%), the prevalence of HIV infection in this population was 9.5% (95% CI, 8.1%-11.1%), and the rate of coinfection of HSV-2 and HIV was 3.2% (95% CI, 2.4%-4.3%). Multivariate logistic regression analysis showed that risk factors for HSV-2 infection included age older than 30 years, education level lower than senior high school, involvement in commercial sex work, and HIV-positive status. Education level lower than junior high school and history of sexual abuse were associated with HSV-2/HIV coinfection. CONCLUSIONS: The high prevalence of HSV-2 infection and HSV-2/HIV coinfection among MSM in China suggests that an increased focus on HSV control is warranted within China's prevention and intervention programs targeted toward MSM.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Herpes Genital/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Adolescente , Adulto , Western Blotting , China/epidemiologia , Coinfecção , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Humanos , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
19.
Front Cell Neurosci ; 16: 882127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634464

RESUMO

Low-intensity focused ultrasound (LIFU) has been shown to provide effective activation of the spinal cord neurocircuits. The aim of this study was to investigate the effects of LIFU in order to alleviate spasticity following spinal cord injury (SCI) by activating the spinal neurocircuits and increasing the expression of the neuronal K-Cl cotransporter KCC2. Adult male Sprague Dawley (SD) rats (220-300 g) were randomly divided into a sham control group, a LIFU- group, and a LIFU+ group. The mechanical threshold hold (g) was used to evaluate the behavioral characteristics of spasm. Electromyography (EMG) was used to assess activation of the spinal cord neurocircuits and muscle spontaneous contraction. Spasticity was assessed by frequency-dependent depression (FDD). The expression of KCC2 of the lumbar spinal cord was determined via western blot (WB) and immunofluorescence (IF) staining. The spinal cord neurocircuits were activated by LIFU simulation, which significantly reduced the mechanical threshold (g), FDD, and EMG recordings (s) after 4 weeks of treatment. WB and IF staining both demonstrated that the expression of KCC2 was reduced in the LIFU- group (P < 0.05). After 4 weeks of LIFU stimulation, expression of KCC2 had significantly increased (P < 0.05) in the LIFU+ group compared with the LIFU- group. Thus, we hypothesized that LIFU treatment can alleviate spasticity effectively and upregulate the expression of KCC2 in the L4-L5 section of SCI rats.

20.
J Pers Med ; 12(3)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35330449

RESUMO

(1) Background: Our study investigated whether monocyte distribution width (MDW) could be used in emergency department (ED) settings as a predictor of prolonged length of stay (LOS) for patients with COVID-19. (2) Methods: A retrospective cohort study was conducted; patients presenting to the ED of an academic hospital with confirmed COVID-19 were enrolled. Multivariable logistic regression models were used to obtain the odds ratios (ORs) for predictors of an LOS of >14 days. A validation study for the association between MDW and cycle of threshold (Ct) value was performed. (3) Results: Fever > 38 °C (OR: 2.82, 95% CI, 1.13−7.02, p = 0.0259), tachypnea (OR: 4.76, 95% CI, 1.67−13.55, p = 0.0034), and MDW ≥ 21 (OR: 5.67, 95% CI, 1.19−27.10, p = 0.0269) were robust significant predictors of an LOS of >14 days. We developed a new scoring system in which patients were assigned 1 point for fever > 38 °C, 2 points for tachypnea > 20 breath/min, and 3 points for MDW ≥ 21. The optimal cutoff was a score of ≥2. MDW was negatively associated with Ct value (ß: −0.32 per day, standard error = 0.12, p = 0.0099). (4) Conclusions: Elevated MDW was associated with a prolonged LOS.

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