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1.
Clin Immunol ; 259: 109879, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38142901

RESUMO

The impact of Omicron infections on the clinical outcome and immune responses of myasthenia gravis (MG) remained largely unknown. From a prospective multicenter MG cohort (n = 189) with 197 myasthenic crisis (MC), we finally included 41 independent MG patients to classify into two groups: the Omicron Group (n = 13) and the Control Group (n = 28). In this matched cohort study, all-cause mortality was 7.69% (1/13) in Omicron Group and 14.29% (4/28) in Control Group. A higher proportion of elevated serum IL-6 was identified in the Omicron Group (88.89% vs 52.38%, P = 0.049). In addition, the proportions of CD3+CD8+T in lymphocytes and Tregs in CD3+CD4+ T cells were significantly elevated in the Omicron Group (both P = 0.0101). After treatment, the Omicron Group exhibited a marked improvement in MG-ADL score (P = 0.026) and MG-QoL-15 (P = 0.0357). MCs with Omicron infections were associated with elevated serum IL-6 and CD3+CD8+T response. These patients tended to present a better therapeutic response after fast-acting therapies and anti-IL-6 treatment.


Assuntos
Interleucina-6 , Miastenia Gravis , Humanos , Estudos Prospectivos , Estudos de Coortes , Qualidade de Vida , Miastenia Gravis/tratamento farmacológico
2.
Dermatology ; 237(1): 56-65, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32349003

RESUMO

BACKGROUND: Psoriasis is an immune-mediated inflammatory skin disease in conjunction with the systemic inflammatory process. It appears to be related to increased risks of cardiovascular disease events, especially in severe cases. The hemostatic balance is disrupted due to the prothrombotic bias in psoriasis, which might be mainly preserved by platelet hyperactivity. Platelets are also immune cells that initiate and regulate immune and inflammatory processes, except as the principal mediator of hemostasis and thrombosis, and platelet dysfunction is deeply involved in the pathogenesis of psoriasis. SUMMARY: The aim of this study is to perform a review that expounds abnormal platelet function in psoriasis and explains the important role of platelets in the pathogenic mechanism of psoriasis in order to provide new targets for comprehensive medical treatment.


Assuntos
Plaquetas/fisiologia , Ativação Plaquetária/fisiologia , Psoríase/etiologia , Humanos
3.
Clin Lab ; 65(7)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31307160

RESUMO

BACKGROUND: Reticulocyte count (RET) has been used for many years to estimate the erythropoietic activity of the bone marrow. Fully automated methods not only provide enhanced precision and accuracy, but also enable reliable measurements of mRNA content and cellular indices. However, problems still exist, such as interference. The aim of the present study was to investigate the interferents of Sysmex XN 9000 reticulocyte analysis and ensure the accuracy of the results. METHODS: We collected a total of 510 specimens from normal control patients and patients with various diseases including anemias, leukemias, infectious diseases, immune diseases, kidney disease, etc. Correlation of the agreement for reticulocytes between the new methylene blue (NMB) visual microscopy method and automated reticulocyte counting was evaluated by paired sample method according to the CLSI-ICSH document H44-A2-Methods for Reticulocyte Count. Blood smear microscopic examination was carried out on the disturbed samples, and the interferents were analyzed with the medical history, flagging algorithms, the warning information, and the microscopic examination. RESULTS: A total of 44 (8.6%) cases exhibited interference. The main interferents of spuriously high reticulocyte count were caused by parasites, such as malaria, as well as suspicious autofluorescence due to drugs, while the main interferents of spuriously low reticulocyte count were caused by RBC fragments. CONCLUSIONS: Detection of potential interferences may be accomplished through alarm information and flagging algorithms incorporated into the instrument and by examination of a blood film to ensure absence of relevant interferences.


Assuntos
Automação Laboratorial/instrumentação , Contagem de Células Sanguíneas/instrumentação , Contagem de Reticulócitos/instrumentação , Reticulócitos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Automação Laboratorial/métodos , Contagem de Células Sanguíneas/métodos , Criança , Feminino , Humanos , Leucemia/sangue , Malária/sangue , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Contagem de Reticulócitos/métodos , Reticulócitos/citologia , Adulto Jovem
4.
Microbiol Spectr ; : e0058324, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869308

RESUMO

Malaria infection remains a serious threat to human health worldwide. Rapid and accurate detection technology is crucial for preventing malaria transmission and minimizing damage. We aimed to establish and validate a new rapid molecular detection method for malaria, called EasyNAT Malaria Assay, targeting Plasmodium vivax, Plasmodium falciparum, Plasmodium ovale, and Plasmodium malariae. The analytical performance of EasyNAT Malaria Assay was determined using positive materials. We identified 42 clinical samples as malaria positive and 95 negative samples. Each sample was examined by four methods: light microscopy, rapid diagnostic test, EasyNAT Malaria Assay, and digital PCR. Diagnostic accuracy and clinical performance were evaluated. The limit of detection (LOD)95% of EasyNAT Malaria was consistently 40 parasites/mL. It specifically amplified Plasmodium and performed with reliable repeatability and reproducibility. In 137 clinical samples, EasyNAT Malaria detected four more positive samples than microscopic examination and two more positive samples than rapid diagnostic test (RDT). One clinical sample was positive only under digital PCR. However, no significant differences statistically in sensitivity or specificity were observed. Compared with microscopy, the total, positive, and negative concordance rates of EasyNAT were 97.08%, 100%, and 95.79%, respectively. Enhanced diagnostic accuracy of EasyNAT Malaria in patients who had taken anti-malarial medication before their clinical appointment was observed. The EasyNAT Malaria Assay has good detection efficiency for clinical samples, presents a promising molecular detection tool in clinical practice, and is particularly suitable for rapid screening of high-risk populations in the emergency room. IMPORTANCE: This study established and validated EasyNAT Malaria Assay as a promising molecular detection tool for malaria screening of high-risk populations in clinical practice. This novel isothermal amplification method may effectively facilitate the rapid diagnosis of malaria and prevent its transmission.

5.
Pract Lab Med ; 40: e00411, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38846327

RESUMO

Background: Pandy's test is used to assess the globulin level in cerebrospinal fluid (CSF). As a semi-quantitative manual method, the practicality and clinical value of Pandy's test has been challenged. Objective: We tend to summarize the relationship between CSF total protein (CSF-TP) quantification and Pandy's results, providing a formula to estimate Pandy's results merely by CSF-TP value. Methods: This retrospective study involved 1090 cases hospitalized in Huashan Hospital during 1/1/2023 to 20/4/2023. All samples were divided into six group based on their Pandy's results. Their corresponding CSF-TP quantitative results were subsequently analyzed and summarized. Another 364 patients were also gathered for verification. Results: The turbidity of samples won't affect examiners'ocular inspection and interpretation of Pandy's tests in positive groups. The results of Pandy's tests can be deduced based on CSF-TP quantitative results according to following rules: CSF-TP quantitative results 0-614 mg/L for Pandy negative (-), 615-1322 mg/L for extremely weak positive (±), 1323-2953 mg/L for weak positive (1+), 2954-6561 mg/L for medium positive results (2+), 6562-13007 mg/L for strong positive results (3+) and CSF-TP results >13007 for strongest positive (4+). The quantitative range above was experimentally verified as effective and correct by calculating the agreement rate through another 364 samples and the R ratio of each Pandy group was greater than 90 %. Conclusion: There is an excellent correlation between CSF-TP and Pandy's test. Therefore, CSF-TP quantification test through PROT Slides can be used to infer the results of Pandy's test to accelerate the abolish of this traditional manual test.

6.
Clin Chim Acta ; 562: 119879, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39029646

RESUMO

BACKGROUND: The diagnostic utility of cerebrospinal fluid (CSF) cytology encounters impediments stemming from variability in cell collection techniques and pathologists' morphological acumen, resulting in wide-ranging CSF positivity rates for primary central nervous system lymphomas (PCNSL). Such disparity impacts patient evaluation, treatment stratagem, and prognostication. Thus, this study endeavors to explore liquid biomarkers complementary to CSF cytology or immunophenotype analysis in the diagnosis of CSF involvement. METHODS: 398 newly diagnosed PCNSL patients were categorized into CSF involvement and non-involvement groups based on CSF cytology and immunophenotype analysis. Binary logistic regression analysis was performed on 338 patients to investigate factors predicting CSF involvement and to develop a joint prediction model. An additional cohort of 60 PCNSL patients was recruited for model validation. Statistical analyses included the Mann-Whitney U test for comparing various CSF parameters between two groups. ROC curve analyses were performed for each biomarker to identify PCNSL CSF involvement. RESULTS: The cytokine IL-10 level in CSF has emerged as the most promising biomarker for CSF evaluation, boasting an ROC AUC of 0.922. C-TNFα and soluble C-IL2R demonstrate efficacy in quantifying tumor burden within the CSF. Logistic regression identified C-IL10lg (OR = 30.103, P < 0.001), C-TNC (OR = 1.126, P < 0.001), C-IL2Rlg (OR = 3.743, P = 0.029) as independent predictors for CSF involvement, contributing to a joint predictive model with an AUC of 0.935, sensitivity of 74.1 %, and specificity of 93.0 %. Validation of the model in an independent cohort confirmed its effectiveness, achieving an AUC of 0.9713. CONCLUSIONS: The identification of these feasible biomarkers and the development of an accurate prediction model may facilitate the precise evaluation of CSF status in PCNSL, offering significant advancements in patient management.


Assuntos
Neoplasias do Sistema Nervoso Central , Citocinas , Linfoma , Humanos , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Modelos Logísticos , Citocinas/líquido cefalorraquidiano , Linfoma/líquido cefalorraquidiano , Linfoma/diagnóstico , Idoso , Adulto , Biomarcadores Tumorais/líquido cefalorraquidiano
7.
Clin Chim Acta ; 555: 117801, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38296220

RESUMO

BACKGROUND: This study investigated the performance of the MC-100i, a pre-commercial digital morphology analyzer utilizing a convolutional neural network algorithm, in a multicentric setting involving up to 11 tertiary hospitals in China. METHODS: Blood smears were analyzed by MC-100i, verified by morphologists, and manually differentiated. The classification performance on WBCs and RBCs was evaluated by comparing the classification results using different methods. The PLT and PLT clump counting performance was also assessed. The total assay time including hands-on time was evaluated. RESULTS: The agreements between pre- and post-classification were high for normal WBCs (κ > 0.96) and lower for overall abnormal WBCs (κ = 0.90). The post-classification results correlated well with manual differentials for both normal and abnormal WBCs (r > 0.93), except for basophils (r = 0.8480) and atypical lymphocytes (r = 0.8211). The clinical sensitivity and specificity of each RBC abnormality after verification were above 90 % using microscopy reviews as the reference. The PLTs counted by the MC-100i before and after verification correlated well with those measured by the PLT-O mode (r = 0.98). Moreover, PLT clumps were successfully classified by the analyzer in EDTA-dependent pseudothrombocytopenia blood samples. CONCLUSIONS: The MC-100i is an accurate and reliable digital cell morphology analyzer, offering another intelligent option for hematology laboratories.


Assuntos
Hematologia , Leucócitos , Humanos , Centros de Atenção Terciária , Eritrócitos , China , Reprodutibilidade dos Testes
8.
Clin Chim Acta ; 544: 117338, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37060988

RESUMO

Drugs targeting DNA repair have developed rapidly in cancer therapy, and numerous inhibitors have already been utilized in preclinical and clinical stages. To optimize the selection of patients for treatment, it is essential to discover biomarkers to anticipate chemotherapy response. The DNA mismatch repair (MMR) pathway is closely correlated with cancer susceptibility and plays an important role in the occurrence and development of cancers. Here, we give a concise introduction of the MMR genes and focus on the potential biomarkers of chemotherapeutic response and resistance. It has been clarified that the status of MMR may affect the outcome of chemotherapy. However, the specific underlying mechanisms as well as contradictory results continue to raise considerable controversy and concern. In this review, we summarize the current literature to provide a general overview.


Assuntos
Reparo de Erro de Pareamento de DNA , Neoplasias , Humanos , Reparo do DNA , Neoplasias/genética , Biomarcadores , Resistencia a Medicamentos Antineoplásicos
9.
Clin Chim Acta ; 539: 70-78, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36495929

RESUMO

BACKGROUND: Blood smear examination through traditional optical microscopy is the gold standard for malaria diagnosis. However, it imposes strict requirements for operational staff and its sensitivity cannot perfectly satisfy the needs of clinical requirements. More sensitive and accurate modern technologies should be applied to this field. Digital PCR (dPCR), as an absolute quantification detection method, can serve as an effective tool to facilitate the diagnosis and classification of different malaria species. OBJECTIVE: We aimed to establish a new multiplex dPCR detection system for four main Plasmodium species: P. vivax, P. falciparum, P. ovale and P. malariae, which can distinguish exact species of malaria by one PCR reaction. METHODS: A total of 39 patients were identified as malaria-positive by microscopic examination in Huashan Hospital from 2016 to 2021; seventy blood samples from these patients were collected. Additionally, 20 healthy individuals, 20 patients with fever and 6 patients with other types of blood parasites infection were also included in this study. Each blood sample was subjected to examination by both blood smears and dPCR. By optimizing four different fluorescence-labeled probes in one reaction system, dPCR permitted the performance of accurate quantitation and working out the exact number of copies of malaria DNA per microliter in whole blood. Rapid diagnostic tests were also conducted to verify part of the results obtained by dPCR. RESULTS: The dPCR system was able to make rapid diagnosis and quantification of malaria DNA samples. The analytical sensitivity of multiplex dPCR was as low as 0.557 copies/µL (95% CI 0.521 to 0.607), and it had a sensitivity of 98.0% and a specificity of 100% in clinical samples. Additionally, three multiple malaria co-infection samples have been detected by this dPCR system, including one triple malaria infection case. By testing consecutive daily blood samples of Patient 39, dPCR facilitated monitoring the efficacy of drug treatment. It showed that the DNA concentrations of P. falciparum ranged from 5474 copies/µL to 0 copies/µL, which can reflect the efficacy of antimalarials in real time. This study also found that haemocyte samples (plasma removed) rather than whole blood had higher malaria detection capability and an enhanced positive rate. CONCLUSION: The multiplex dPCR system newly established here made a substantial contribution in detecting malaria infection at low concentrations. It is suitable for mixed-infection diagnosis and multi-sample continuous monitoring, and presents a promising candidate as an absolute quantitative tool in clinical practice.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Parasitos , Animais , Humanos , Parasitos/genética , Sensibilidade e Especificidade , Malária/diagnóstico , Malária/parasitologia , Malária Vivax/diagnóstico , Malária Vivax/parasitologia , Reação em Cadeia da Polimerase Multiplex/métodos , Plasmodium vivax/genética , Plasmodium falciparum/genética
10.
Epigenomics ; 15(24): 1293-1308, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38126139

RESUMO

Aims: The systematic identification of molecular features correlated with the clinical status of gastric cancer (GC) in patients is significant, although such investigation remains insufficient. Methods: GC subtyping based on RNA sequencing, copy number variation and DNA methylation data were derived from The Cancer Genome Atlas program. Prognostics lncRNA biomarkers for GC were identified by univariate Cox, LASSO and SVM-RFE analysis. Results: Three molecular subtypes with significant survival discrepancies, and their specific DEmRNAs and DElncRNAs were identified. Three reliable prognostic-associated lncRNA, including LINC00670, LINC00452 and LINC00160, were selected for GC. Conclusion: Our findings expanded the understanding on the regulatory network of lncRNAs in GC, providing potential targets for prognosis and treatment of GC patients.


Assuntos
RNA Longo não Codificante , Neoplasias Gástricas , Humanos , Prognóstico , RNA Longo não Codificante/genética , Multiômica , Neoplasias Gástricas/genética , Variações do Número de Cópias de DNA , Redes Reguladoras de Genes , Biomarcadores Tumorais/genética
11.
Ann Med ; 53(1): 1370-1376, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34405745

RESUMO

BACKGROUND: To the best of our knowledge, the association of inflammatory parameters with hepatic hydatid disease (HD) has not been investigated in a single study. We aimed to evaluate the potential value of inflammatory indices in this disorder. METHODS: The retrospective study including 114 patients was performed from January 2016 to November 2019. Clinical characteristics and laboratory data for all participants were collected and analysed. The levels of inflammatory parameters were compared in the patient and control group, the predictive value of these inflammatory parameters was assessed by the logistic regression analysis and receiver operating characteristic curve, and differences between pre- and post-surgical operations were compared by pair tests. RESULTS: Significantly higher levels of platelet distribution width (PDW), eosinophil percentage (EOS %), neutrophil to lymphocyte ratio (NLR), gamma-glutamyl transpeptidase to platelet ratio (GPR) and alkaline phosphatase to platelet ratio (APPR) and lower levels of platelet (PLT) and prognostic nutritional index (PNI) were observed in patients than in controls. Multivariate analyses showed that hydatid could induce the abnormal levels of these parameters, of which APPR and PNI had more obvious changes as compared to other parameters. The levels of PDW and APPR significantly decreased after surgical treatment. CONCLUSIONS: Inflammatory parameters closely associated with the hepatic HD could be used in the evaluation of treatment as assistant indexes.KEY MESSAGEHydatid disease (HD) seriously endangers public health and economic development.Inflammatory parameters that are readily available and acceptable in routine clinical practice could be closely associated with HD.Inflammatory parameters could be used in the evaluation of disease development by combing with histological and radiological results in future studies.


Assuntos
Equinococose/complicações , Inflamação , Linfócitos , Adulto , Fosfatase Alcalina/sangue , Plaquetas , Estudos de Casos e Controles , Equinococose/imunologia , Humanos , Contagem de Leucócitos , Pessoa de Meia-Idade , Neutrófilos , Curva ROC , Estudos Retrospectivos , gama-Glutamiltransferase/sangue
12.
Cell Death Dis ; 12(5): 485, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986248

RESUMO

Long noncoding RNAs (lncRNAs) have emerged as a new class of regulatory molecules implicated in therapeutic resistance, yet the mechanisms underlying lncRNA-mediated oxaliplatin resistance in colorectal cancer (CRC) are poorly understood. In this study, lncRNA P53 inHibiting LncRNA (PiHL) was shown to be highly induced in oxaliplatin-resistant CRC cells and tumor tissues. In vitro and in vivo models clarified PiHL's role in conferring resistance to oxaliplatin-induced apoptosis. PiHL antagonized chemosensitivity through binding with EZH2, repressing location of EZH2 to HMGA2 promoter, and downregulating methylation of histone H3 lysine 27 (H3K27me3) level in HMGA2 promoter, thus activating HMGA2 expression. Furthermore, HMGA2 upregulation induced by PiHL promotes PI3K/Akt phosphorylation, which resulted in increased oxaliplatin resistance. We also found that transcription factor KLF4 was downregulated in oxaliplatin-resistant cells, and KLF4 negatively regulated PiHL expression by binding to PiHL promoter. In vivo models further demonstrated that treatment of oxaliplatin-resistant CRC with locked nucleic acids targeting PiHL restored oxaliplatin response. Collectively, this study established lncRNA PiHL as a chemoresistance promoter in CRC, and targeting PiHL/EZH2/HMGA2/PI3K/Akt signaling axis represents a novel choice in the investigation of drug resistance.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Oxaliplatina/uso terapêutico , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Humanos , Fator 4 Semelhante a Kruppel , Camundongos , Camundongos Nus , Oxaliplatina/farmacologia , Prognóstico , Transfecção
13.
Infect Genet Evol ; 70: 84-89, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30807842

RESUMO

Carbapenemase-producing Klebsiella pneumoniae has emerged and spread widely throughout the world. The mechanisms involved remain unclear. To provide insight, five plasmids were obtained from carbapenemase-producing K. pneumoniae clinical isolates. The five sequences were acquired, aligned and analyzed. In addition to the blaKPC-2 gene, which encodes beta lactamase, essentially all the plasmids contained a putative anti-restriction protein-encoding gene, KlcAHS. The KlcAHS gene was found in 98.2% of the blaKPC-2-positive, imipenem-resistant K. pneumoniae clinical isolates and in <1% of the blaKPC-2-negative control group. A searched of the GenBank database indicated that KlcAHS was mainly submitted by Chinese investigators beginning in 2010. Seventeen different KlcA amino acid sequences were found in the database using the restricting words: KlcA and Klebsiella pneumoniae. These sequences were used to generate a phylogenetic tree via MEGA6 software, revealing a distant evolutionary relationship between KlcAHS and other KlcAs. The secondary structure of KlcAHS, predicted with PROMALS3D software, exhibited highly conserved α-helices and ß-strands. KlcAHS expressed anti-restriction activity in vivo. In summary, KlcAHS genes are ubiquitous in blaKPC-2-positive Klebsiella pneumoniae clinical isolates collected at Huashan Hospital, China. The KlcAHS protein possesses a secondary structure similar to that exhibited by anti-restriction proteins and displays anti-restriction activity. As such, KlcAHS is a probable factor in the accelerated spread of blaKPC-2 and carbapenem-resistance among clinical, K. pneumoniae isolates.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Proteínas Virais/genética , beta-Lactamases/genética , China , Humanos , Epidemiologia Molecular , Filogenia , Plasmídeos/genética
14.
Front Microbiol ; 9: 542, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29628918

RESUMO

Streptococcus pyogenes, also known as group A Streptococcus (GAS), is one of the top 10 infectious causes of death worldwide. Macrolide and tetracycline resistant GAS has emerged as a major health concern in China coinciding with an ongoing scarlet fever epidemic. Furthermore, increasing rates of fluoroquinolone (FQ) non-susceptibility within GAS from geographical regions outside of China has also been reported. Fluoroquinolones are the third most commonly prescribed antibiotic in China and is an therapeutic alternative for multi-drug resistant GAS. The purpose of this study was to investigate the epidemiological and molecular features of GAS fluoroquinolone (FQ) non-susceptibility in Shanghai, China. GAS (n = 2,258) recovered between 2011 and 2016 from children and adults were tested for FQ-non-susceptibility. Efflux phenotype and mutations in parC, parE, gyrA, and gyrB were investigated and genetic relationships were determined by emm typing, pulsed-field gel electrophoresis and phylogenetic analysis. The frequency of GAS FQ-non-susceptibility was 1.3% (30/2,258), with the phenotype more prevalent in GAS isolated from adults (14.3%) than from children (1.2%). Eighty percent (24/30) of FQ-non-susceptible isolates were also resistant to both macrolides (ermB) and tetracycline (tetM) including the GAS sequence types emm12, emm6, emm11, and emm1. Genomic fingerprinting analysis of the 30 isolates revealed that non-susceptibility may arise in various genetic backgrounds even within a single emm type. No efflux phenotype was observed in FQ non-susceptible isolates, and molecular analysis of the quinolone resistance-determining regions (QRDRs) identified several sequence polymorphisms in ParC and ParE, and none in GyrA and GyrB. Expansion of this analysis to 152 publically available GAS whole genome sequences from Hong Kong predicted 7.9% (12/152) of Hong Kong isolates harbored a S79F ParC mutation, of which 66.7% (8/12) were macrolide and tetracycline resistant. Phylogenetic analysis of the parC QRDR sequences suggested the possibility that FQ resistance may be acquired through inter-species lateral gene transfer. This study reports the emergence of macrolide, tetracycline, and fluoroquinolone multidrug-resistant clones across several GAS emm types including emm1 and emm12, warranting continual surveillance given the extensive use of fluoroquinolones in clinical use.

15.
Front Microbiol ; 7: 1308, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27625635

RESUMO

Streptococcus agalactiae, a colonizing agent in pregnant women and the main cause of neonatal sepsis and meningitis, has been increasingly associated with invasive disease in nonpregnant adults. We collected a total of 87 non-repetitive S. agalactiae isolates causing community-acquired (CA) and hospital-acquired (HA) infections in nonpregnant adults from a teaching hospital in Shanghai between 2009 and 2013. We identified and characterized their antibiotic resistance, sequence type (ST), serotype, virulence, and biofilm formation. The most frequent STs were ST19 (29.9%), ST23 (16.1%), ST12 (13.8%), and ST1 (12.6%). ST19 had significantly different distributions between CA- and HA-group B Streptococci (GBS) isolates. The most frequent serotypes were III (32.2%), Ia (26.4%), V (14.9%), Ib (13.8%), and II (5.7%). Serotype III/ST19 was significantly associated with levofloxacin resistance in all isoates. The HA-GBS multidrug resistant rate was much higher than that of CA-GBS. Virulence genes pavA, cfb were found in all isolates. Strong correlations exist between serotype Ib (CA and HA) and surface protein genes spb1 and bac, serotype III (HA) and surface protein gene cps and GBS pilus cluster. The serotype, epidemic clone, PFGE-based genotype, and virulence gene are closely related between CA-GBS and HA-GBS, and certain serotypes and clone types were significantly associated with antibiotic resistance. However, CA-GBS and HA-GBS still had significant differences in their distribution of clone types, antibiotic resistance, and specific virulence genes, which may provide a basis for infection control.

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