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1.
J Magn Reson Imaging ; 59(5): 1820-1831, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37830268

RESUMO

BACKGROUND: The impact of left ventricular mechanical dyssynchrony (LVMD) on the long-term prognosis of ST-segment elevation myocardial infarction (STEMI) is unclear. HYPOTHESIS: MR uniformity ratio estimates (URE) can detect LVMD and assess STEMI prognosis. STUDY TYPE: Retrospective analysis of a prospective multicenter registry (EARLY-MYO trial, NCT03768453). POPULATION: Overall, 450 patients (50 females) with first-time STEMI were analyzed, as well as 40 participants without cardiovascular disease as controls. FIELD STRENGTH/SEQUENCE: 3.0-T, balanced steady-state free precession cine and late gadolinium enhancement imaging. ASSESSMENT: MRI data were acquired within 1 week of symptom onset. Major adverse cardiovascular events (MACEs), including cardiovascular death, nonfatal re-infarction, hospitalization for heart failure, and stroke, were the primary clinical outcomes. LVMD was represented by circumferential URE (CURE) and radial URE (RURE) calculated using strain measurements. The patients were grouped according to clinical outcomes or URE values. Patients' clinical characteristics and MR indicators were compared. STATISTICAL TESTS: The Student's t-test, Mann-Whitney U test, chi-square test, Fisher's exact test, receiver operating characteristic curve analysis with area under the curve, Kaplan-Meier analysis, Cox regression, logistic regression, intraclass correlation coefficient, c-index, and integrated discrimination improvement were used. P < 0.05 was considered statistically significant. RESULTS: CURE and RURE were significantly lower in patients with STEMI than in controls. The median follow-up was 60.5 months. Patients with both lower CURE and RURE values experienced a significantly higher incidence of MACEs by 3.525-fold. Both CURE and RURE were independent risk factors for MACEs. The addition of UREs improved diagnostic efficacy and risk stratification based on infarct size and left ventricular ejection fraction (LVEF). The indicators associated with LVMD included male sex, serum biomarkers (peak creatine phosphokinase and cardiac troponin I), infarct size, and LVEF. DATA CONCLUSION: CURE and RURE may be useful to evaluate long-term prognosis after STEMI. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Humanos , Masculino , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Volume Sistólico , Função Ventricular Esquerda , Estudos Prospectivos , Meios de Contraste , Estudos Retrospectivos , Gadolínio , Imageamento por Ressonância Magnética/métodos , Prognóstico , Intervenção Coronária Percutânea/efeitos adversos , Imagem Cinética por Ressonância Magnética/métodos
2.
J Bacteriol ; 205(8): e0018723, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37439688

RESUMO

The development of novel antibiotic adjuvants is imminent because of the frequent emergence of resistance in Gram-negative bacteria, which severely restricts the efficiency and longevity of commonly used clinical antibiotics. It is reported that famotidine, a clinical inhibitor of gastric acid secretion, enhances the antibacterial activity of rifamycin antibiotics, especially rifampicin, against Gram-negative bacteria and reverses drug resistance. Studies have shown that famotidine disrupts the cell membrane of Acinetobacter baumannii and inhibits the expression of the outer membrane protein ompA gene, while causing a dissipation of the plasma membrane potential, compensatively upregulating the pH gradient and ultimately increasing the accumulation of reactive oxygen species by leading to increased bacterial mortality. In addition, famotidine also inhibited the efflux pump activity and the biofilm formation of A. baumannii. In the Galleria mellonella and mouse infection models, the combination of famotidine and rifampicin increased the survival rate of infected animals and decreased the bacterial load in mouse organs. In conclusion, famotidine has the potential to be a novel rifampicin adjuvant, providing a new option for the treatment of clinical Gram-negative bacterial infections. IMPORTANCE In this study, famotidine was discovered for the first time to have potential as an antibiotic adjuvant, enhancing the antibacterial activity of rifamycin antibiotics against A. baumannii and overcoming the limitations of drug therapy. With the discovery of novel applications for the guanidine-containing medication famotidine, the viability of screening prospective antibiotic adjuvants from guanidine-based molecules was further explored. In addition, famotidine exerts activity by affecting the OmpA protein of the cell membrane, indicating that this protein might be used as a therapeutic drug target to treat A. baumannii infections.


Assuntos
Acinetobacter baumannii , Rifampina , Animais , Camundongos , Rifampina/farmacologia , Acinetobacter baumannii/metabolismo , Famotidina/metabolismo , Estudos Prospectivos , Antibacterianos/metabolismo , Modelos Animais de Doenças , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla
3.
J Magn Reson Imaging ; 58(4): 1084-1097, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36688928

RESUMO

BACKGROUND: Differentiating hypertrophic cardiomyopathy (HCM) from hypertensive heart disease (HHD) is challenging. PURPOSE: To identify differences between HCM and HHD on a patient basis using MRI. STUDY TYPE: Retrospective. POPULATION: A total of 219 subjects, 148 in phase I (baseline data and algorithm development: 75 HCM, 33 HHD, and 40 controls) and 71 in phase II (algorithm validation: 56 HCM and 15 HHD). FIELD STRENGTH/SEQUENCE: Contrast-enhanced inversion-prepared gradient echo and cine-balanced steady-state free precession sequences at 3.0 T. ASSESSMENT: MRI parameters assessed included left ventricular (LV) ejection fraction (LVEF), LV end systolic and end diastolic volumes (LVESV and LVEDV), mean maximum LV wall thickness (MLVWT), LV global longitudinal and circumferential strain (GRS, GLS, and GCS), and native T1. Parameters, which were significantly different between HCM and HHD in univariable analysis, were entered into a principal component analysis (PCA). The selected components were then introduced into a multivariable regression analysis to model an integrated algorithm (IntA) for screening the two disorders. IntA performance was assessed for patients with and without LGE in phase I (development) and phase II (validation). STATISTICAL TESTS: Univariable regression, PCA, receiver operating curve (ROC) analysis. A P value <0.05 was considered statistically significant. RESULTS: Derived IntA formulation included LVEF, LVESV, LVEDV, MLVWT, and GCS. In LGE-positive subjects in phase l, the cutoff point of IntA ≥81 indicated HCM (83% sensitivity and 91% specificity), with the area under the ROC curve (AUC) of 0.900. In LGE-negative subjects, a higher possibility of HCM was indicated by a cutoff point of IntA ≥84 (100% sensitivity and 82% specificity), with an AUC of 0.947. Validation of IntA in phase II resulted in an AUC of 0.846 in LGE-negative subjects and 0.857 in LGE-positive subjects. DATA CONCLUSION: A per-patient-based IntA algorithm for differentiating HCM and HHD was generated from MRI data and incorporated FT, LGE and morphologic parameters. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 2.


Assuntos
Cardiomiopatia Hipertrófica , Cardiopatias , Hipertensão , Humanos , Estudos Retrospectivos , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Função Ventricular Esquerda , Hipertensão/complicações , Hipertensão/diagnóstico por imagem , Meios de Contraste , Imagem Cinética por Ressonância Magnética
4.
Fish Shellfish Immunol ; 135: 108660, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36940784

RESUMO

Aeromonas veronii is an important aquatic zoonotic, which elicits a range of diseases, such as haemorrhagic septicemia. To develop an effective oral vaccine against Aeromonas veronii infection in carp, the Aeromonas veronii adhesion (Aha1) gene was used as a target molecule to attach to intestinal epithelial cells. Two anchored recombinant. Lactic acid bacteria strains (LC-pPG-Aha1 1038 bp and LC-pPG-Aha1-LTB 1383 bp) were constructed by fusing them with the E. coli intolerant enterotoxin B subunit (LTB) gene and using Lactobacillus casei as antigen delivery vector to evaluate immune effects of these in carp. Western blotting and immunofluorescence were used to confirm that protein expression was successful. Additionally, levels of specific IgM in serum and the activities of ACP, AKP, SOD, LYS, C3, C4, and lectin enzymes-were assessed. Cytokines IL-10, IL-1ß, TNF-α, IgZ1, and IgZ2 were measured in the liver, spleen, kidney, intestines, and gills tissue by qRT-PCR, which showed an increasing trend compared with the control group (P < 0.05). A colonization assay showed that the two L. casei recombinants colonized the middle and hind intestines of immunized fish. When immunized carp were experimentally challenged with Aeromonas veronii the relative percentage protection of LC-pPG-Aha1 was 53.57%, and LC-pPG-Aha1-LTB was 60.71%. In conclusion, these results demonstrate that Aha1 is a promising candidate antigen when it is displayed on lactic acid bacteria (Lc-pPG-Aha1 and Lc-pPG-Aha1-LTB) seems promising for a mucosal therapeutic approach. We plan to investigate the molecular mechanism of the L. casei recombinant in regulating the intestinal tissue of carp in future studies.


Assuntos
Carpas , Doenças dos Peixes , Lacticaseibacillus casei , Animais , Aeromonas veronii , Escherichia coli , Imunização , Adjuvantes Imunológicos/farmacologia , Doenças dos Peixes/prevenção & controle
5.
BMC Vet Res ; 19(1): 255, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053138

RESUMO

BACKGROUND: Multidrug resistance in Enterobacteriaceae including resistance to quinolones is rising worldwide. The development of resistance may lead to the emergence of new transmission mechanisms. In this study, the collection of different E. coli was performed from animals and subjected to subsequent procedures including pulsed-field gel electrophoresis, micro-broth dilution method, polymerase chain reaction. Whole genome sequencing of E. coli C3 was performed to detect the affinity, antimicrobial resistance and major carriers of the isolates. RESULTS: A total of 66 E. coli were isolated and their antibiotic resistance genes, frequency of horizontal transfer and genetic environment of E. coli C3 were determined. The results showed there were both different and same types in PFGE typing, indicating clonal transmission of E. coli among different animals. The detection of antimicrobial resistance and major antibiotic resistance genes and the plasmid transfer results showed that strains from different sources had high levels of resistance to commonly used clinical antibiotics and could be spread horizontally. Whole-genome sequencing discovered a novel ICE mobile element. CONCLUSION: In summary, the antimicrobial resistance of E. coli in northeast China is a serious issue and there is a risk of antimicrobial resistance transmission. Meanwhile, a novel ICE mobile element appeared in the process of antimicrobial resistance formation.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Escherichia coli/veterinária , Enterobacteriaceae , China , Testes de Sensibilidade Microbiana/veterinária , Plasmídeos , Eletroforese em Gel de Campo Pulsado/veterinária , beta-Lactamases/genética
6.
Radiol Med ; 128(11): 1372-1385, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37640898

RESUMO

BACKGROUND: The prognostic role of diastolic dysfunction measured by the circumferential peak early diastolic strain rate (PEDSR) on ST-elevation myocardial infarction (STEMI) is not completely established. OBJECTIVES: We aimed to investigate the prognostic value of diastolic function by measuring PEDSR within 1 week after STEMI. METHODS: The cardiac magnetic resonance (CMR) pictures of 420 subjects from a clinical registry study (NCT03768453) were analyzed and the composite major adverse cardiac events (MACEs) were followed up. RESULTS: The PEDSR of patients was significantly lower compared with that of control subjects (P < 0.001). Within the median follow-up period of 52 months, PEDSR of patients who experienced MACEs deceased more significantly than that of patients without MACEs (P < 0.001). After adjusting with clinical or CMR indexes, per 0.1/s reduction of PEDSR increased the risks of MACEs to 1.402 or 1.376 fold and the risk of left ventricular (LV) remodeling to 1.503 or 1.369 fold. When PEDSR divided by best cutoff point, significantly higher risk of MACEs (P < 0.001) and more remarkable LV remodeling (P < 0.001) occurred in patients with PEDSR ≤ 0.485/s. Moreover, when adding the PEDSR to the conventional prognostic factors such as LV ejection fraction and infarction size, better prognostic risk classification models were created. Finally, aging, tobacco use, remarkable LV remodeling, and a low LV ejection fraction were factors related with the reduction of PEDSR. CONCLUSIONS: Diastolic dysfunction has an important prognostic effect on patients with STEMI. Measurement of the PEDSR in the acute phase could serve as an effective index to predict the long-term risk of MACEs and cardiac remodeling.


Assuntos
Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Coração , Imageamento por Ressonância Magnética , Função Ventricular Esquerda , Volume Sistólico , Remodelação Ventricular , Valor Preditivo dos Testes
7.
Int J Mol Sci ; 24(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37240435

RESUMO

Antibiotic tolerance has become an increasingly serious crisis that has seriously threatened global public health. However, little is known about the exogenous factors that can trigger the development of antibiotic tolerance, both in vivo and in vitro. Herein, we found that the addition of citric acid, which is used in many fields, obviously weakened the bactericidal activity of antibiotics against various bacterial pathogens. This mechanistic study shows that citric acid activated the glyoxylate cycle by inhibiting ATP production in bacteria, reduced cell respiration levels, and inhibited the bacterial tricarboxylic acid cycle (TCA cycle). In addition, citric acid reduced the oxidative stress ability of bacteria, which led to an imbalance in the bacterial oxidation-antioxidant system. These effects together induced the bacteria to produce antibiotic tolerance. Surprisingly, the addition of succinic acid and xanthine could reverse the antibiotic tolerance induced by citric acid in vitro and in animal infection models. In conclusion, these findings provide new insights into the potential risks of citric acid usage and the relationship between antibiotic tolerance and bacterial metabolism.


Assuntos
Antibacterianos , Estresse Oxidativo , Animais , Antibacterianos/farmacologia , Bactérias , Ciclo do Ácido Cítrico
8.
Int Heart J ; 64(1): 81-84, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36682766

RESUMO

Epicardial right-sided accessory pathway (AP) ablation is challenging. In rare cases, the atrial insertion of the AP is related to unconventional sites and associated with repeated and complex ablation procedures. In this study, we report a case of right free wall diverticulum-related AP with a distinct surface electrocardiogram (ECG).A 45-year-old male patient with repetitive palpitation for 2 years was referred for an electrophysiological (EP) study. His resting surface ECG showed manifest ventricular preexcitation with a negative delta wave and a "QS" wave in precordial lead V1, which is most consistent with right mid-septal AP.In the EP study, orthodromic atrioventricular reentrant tachycardia could be easily induced with the earliest atrial activation at the right atrium (RA) free wall, but the AP failed to be blocked by ablating the earliest activation on the tricuspid annulus edge. An epicardial free wall AP was then suspected.Inadvertent catheter manipulation into a narrow and long chamber was noted on the RA geometry. Angiography via contrast injection from the ablation tip revealed a diverticulum extending from the RA to the right ventricle side. The epicardial AP was suspected to be related to this diverticulum. The earliest atrial activation, as shown through a detailed activation mapping, was located at the entrance of the diverticulum. Subsequent ablation at the atrial insertion site successfully abolished the antegrade and retrograde AP conduction without any complication. A postprocedural computed tomography scan proved the presence of a free wall diverticulum associated with the right atrial appendage.A diverticulum-related AP at RA free wall might exhibit surface ECGs mimicking that of an AP at the RA septum. The approach targeting the atrial insertion of the epicardial AP is effective and might be facilitated by clarification of structural malformations prior to the ablation procedure.


Assuntos
Feixe Acessório Atrioventricular , Ablação por Cateter , Taquicardia Supraventricular , Masculino , Humanos , Pessoa de Meia-Idade , Fascículo Atrioventricular , Arritmias Cardíacas , Átrios do Coração , Taquicardia Supraventricular/cirurgia , Feixe Acessório Atrioventricular/diagnóstico , Feixe Acessório Atrioventricular/cirurgia , Eletrocardiografia , Ablação por Cateter/métodos
9.
Arch Microbiol ; 204(1): 112, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982208

RESUMO

In this study, a bacteriocin PA996 isolated from Pseudomonas azotoformans (P. azotoformans) was purified to homogeneity by ammonium sulphate precipitation and SP-Sepharose column chromatography. P. azotoformans began to grow at 6 h, reached exponential phase at 12-18 h. Bacteriocin PA996 was produced at 18 h and reached a maximum level of 2400 AU/mL. The molecular mass of purified bacteriocin PA996 was estimated by SDS-PAGE and its molecular mass was approximately 50 kDa. By screening in vitro, the bacteriocin PA996 showed an antimicrobial activity against Pasteurella multocida (P. multocida). The bacteriocin PA996 showed antibacterial activity in the range of pH2-10 and it was heat labile. The inhibitory activities were diminished after treatment with proteinase K, trypsin and papain, respectively, while catalase treatment was ineffective. The minimal inhibitory concentration (MIC) and bactericidal kinetics curves showed that the bacteriocin PA996 had a good inhibitory ability against P. multocida. Our data indicate that bacteriocin PA996 could inhibit the growth of P. maltocida and it may have the potential to apply as an alternative therapeutic drug.


Assuntos
Antibacterianos , Bacteriocinas , Pasteurella multocida/efeitos dos fármacos , Pseudomonas , Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana
10.
BMC Cardiovasc Disord ; 21(1): 538, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34772362

RESUMO

BACKGROUND: Macro-reentrant atrial tachycardias (MATs) are a common complication after cardiac valve surgery. The MAT types and the effectiveness of MAT ablation might differ after different valve surgery. Data comparing the electrophysiological characteristics and the ablation results of MAT post-tricuspid or mitral valve surgery are limited. METHODS: Forty-eight patients (29 males, age 56.1 ± 13.3 years) with MAT after valve surgery were assigned to tricuspid valve (TV) group (n = 18) and mitral valve (MV) group (n = 30). MATs were mapped and ablated guided by a three-dimensional navigation system. The one-year clinical effectiveness was compared in two groups. RESULTS: Nineteen MATs were documented in TV group, including 16 cavo-tricuspid isthmus (CTI)-dependent AFL and 3 other MATs at right atrial (RA) free wall, RA septum and left atrial (LA) roof. Thirty-nine MATs were identified in MV group, including15 CTI-dependent AFL, 8 RA free wall scar-related, 2 RA septum scar-related, 8 peri-mitral flutter, 3 LA roof-dependent, 2 LA anterior scar-related, and 1 right pulmonary vein-related MAT. Compared with TV group, MV group had significantly lower prevalence of CTI-dependent AFL (38.5% vs. 84.2%), higher prevalence of left atrial MAT (35.9 vs.5.3%) and higher proportion of patients with left atrial MAT (40 vs. 5.6%), P = 0.02, 0.01 and 0.01, respectively. The acute success rate of MAT ablation (100 vs. 93.3%) and the one-year freedom from atrial tachy-arrhythmias (72.2 vs. 76.5%) was comparable in TV and MV group. No predictor for recurrence was identified. CONCLUSION: Although the types of MATs differed significantly in patients with prior TV or MV surgery, the acute and mid-term effectiveness of MAT ablation was comparable in two groups. TRIAL REGISTRATION: This study was registered as a part of EARLY-MYO-AF clinical trial at the website ClinicalTrials. gov (NCT04512222).


Assuntos
Ablação por Cateter , Eletrocardiografia , Átrios do Coração/fisiopatologia , Valva Mitral/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Taquicardia/fisiopatologia , Valva Tricúspide/cirurgia , Diagnóstico Diferencial , Técnicas Eletrofisiológicas Cardíacas , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia/etiologia , Taquicardia/cirurgia
11.
Fish Shellfish Immunol ; 104: 269-278, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32439515

RESUMO

Aeromonas veronii is a major pathogenic bacterium in humans and animals. When it causes outbreaks, there are enormous economic losses to the aquaculture industry. An effective live attenuated vaccine strain, ΔhisJ, was obtained in our previous studies by gene knockout in Aeromonas veronii TH0426 using the suicide vector pRE112. Here, we evaluated whether the live attenuated vaccine ΔhisJ was suitable for prevention of Aeromonas veronii infection by injection and immersion in loaches. Compared with that of the TH0426 wild-type strain, the virulence of the live vaccine was significantly weakened. Vaccine safety assessment results also indicated that 1 × 107 CFU/mL live vaccine was safe and did not induce clinical symptoms or obvious pathological changes. Additionally, after challenging loaches with Aeromonas veronii TH0426, the relative percent survival of the IN3 injection group was 65.66%, and that of the IM group was 50.78%. Our data show that the live attenuated vaccine ΔhisJ can improve the immune protection rate of loaches. Furthermore, increased enzyme activity parameters (SOD, LZM, ACP, and AKP) in the skin mucus, increased enzyme activity parameters (SOD, LZM, ACP, AKP, and GPx) in the serum, increased specific IgM antibodies and cytokine IL-1ß contents in the serum, and increased cytokine (IL-15, pIgR, IL-1ß, and TNF-α) expression in the liver and spleen were observed. These data are the first to indicate that the live attenuated vaccine ΔhisJ is suitable for the development of a safe and effective vaccine against Aeromonas veronii infection in loach aquaculture.


Assuntos
Aeromonas veronii/imunologia , Vacinas Bacterianas/administração & dosagem , Cipriniformes/imunologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/prevenção & controle , Vacinas Atenuadas/administração & dosagem , Animais , Anticorpos Antibacterianos/sangue , Citocinas/sangue , Citocinas/genética , Citocinas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Imunoglobulina M/sangue , Dose Letal Mediana , Fígado/imunologia , Pele/imunologia , Baço/imunologia
12.
Int J Mol Sci ; 21(3)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046328

RESUMO

Antimicrobial peptides (AMPs) have a unique action mechanism that can help to solve global problems in antibiotic resistance. However, their low therapeutic index and poor stability seriously hamper their development as therapeutic agents. In order to overcome these problems, we designed peptides based on the sequence template XXRXXRRzzRRXXRXX-NH2, where X represents a hydrophobic amino acid like Phe (F), Ile (I), and Leu (L), while zz represents Gly-Gly (GG) or d-Pro-Gly (pG). Showing effective antimicrobial activity against Gram-negative bacteria and low toxicity, designed peptides had a tendency to form an α-helical structure in membrane-mimetic environments. Among them, peptide LRpG (X: L, zz: pG) showed the highest geometric mean average treatment index (GMTI = 73.1), better salt, temperature and pH stability, and an additive effect with conventional antibiotics. Peptide LRpG played the role of anti-Gram-negative bacteria through destroying the cell membrane. In addition, peptide LRpG also exhibited an anti-inflammatory activity by effectively neutralizing endotoxin. Briefly, peptide LRpG has the potential to serve as a therapeutic agent to reduce antibiotic resistance owing to its high therapeutic index and great stability.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Peptídeos Catiônicos Antimicrobianos/química , Bactérias/efeitos dos fármacos , Dicroísmo Circular , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura
13.
Biotechnol Lett ; 41(8-9): 1023-1031, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203568

RESUMO

OBJECTIVE: The present study evaluated the antibacterial activity and mode of action of fibrauretine on Escherichia coli (E. coli) and Staphylococcus aureus, and synergistic effect with kanamycin against multi-drug resistant E. coli. RESULTS: The fibrauretine exhibited inhibitory effect on the growth of the tested bacteria with minimum inhibitory concentration (MIC) and minimum bactericidal concentration of 2.5-5 and 5-10 mg/ml, respectively. Morphological changes of cell microstructure were observed after adding fibrauretine at MIC. The mode of action was further confirmed by measuring release of 260-nm absorbing materials and extracellular potassium ions. Checkerboard dilution test suggested that fibrauretine exhibited synergistic activity when combined with kanamycin (FICI ranging from 0.5625 to 0.625). CONCLUSIONS: Our results indicated that fibrauretine exerted synergistic effect with kanamycin and its antibacterial mode of action mainly attributed to disruption of cell membrane integrity.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Canamicina/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos
14.
Int J Mol Sci ; 20(11)2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31159463

RESUMO

M. avium subsp. paratuberculosis (MAP) is the causative pathogen of Johne's disease, a chronic granulomatous enteritis that principally affects ruminants and can survive, proliferate and disseminate in macrophages. MicroRNAs (miRNAs) are important regulators of gene expression and can impact the processes of cells. To investigate the role of miRNAs in monocyte-derived macrophages (MDMs) during MAP infection, we used high-throughput sequencing technology to analyze small RNA libraries of MAP-infected and control MDMs. The results showed that a total of 21 miRNAs were differentially expressed in MDMs after MAP infection, and 8864 target genes were predicted. A functional analysis showed that the target genes were mainly involved in the MAPK signaling pathway, Toll-like receptor signaling pathway, NF-kappa B signaling pathway and apoptosis. In addition, using a dual-luciferase reporter assay, flow cytometry, and a small interfering (si)RNA knockdown assay, the role of miR-150 in regulating macrophage apoptosis by targeting the programmed cell death protein-4 (PDCD4) was demonstrated. These results provide an experimental basis to reveal the regulatory mechanism of MAP infection and suggest the potential of miRNAs as biomarkers for the diagnosis of Johne's disease in bovines.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose/genética , Macrófagos/metabolismo , Macrófagos/microbiologia , MicroRNAs/genética , Mycobacterium avium subsp. paratuberculosis/fisiologia , Transcriptoma , Animais , Bovinos , Mapeamento Cromossômico , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Macrófagos/imunologia , Camundongos , Paratuberculose/genética , Paratuberculose/microbiologia , Interferência de RNA
15.
Trop Anim Health Prod ; 51(7): 2099-2103, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31104226

RESUMO

Trueperella pyogenes (T. pyogenes) is a worldwide known pathogen of domestic ruminants and pigs causing a wide variety of infections. The objective of this study was to report the presence of major virulence genes in T. pyogenes isolated from pigs with respiratory clinical signs and determine their resistance to antibiotics at the same time. A total of 27 T. pyogenes strains were obtained from Jilin Province, and the nanH, nanP, cbpA, fimC, and fimE virulence genes were detected in 7 (25.9%), 14 (51.9%), 18 (66.7%), 8 (29.6%), and 16 (59.3%) isolates, respectively. All isolates were observed to harbor plo and fimA genes. However, 27 T. pyogenes strains tested negative for fimG gene. Antibiotic susceptibility tests revealed that the isolated strains had extensive drug resistance, all isolates were sensitive to fluoroquinolones and penicillins antibiotics, and high levels of resistance were found to gentamicin (77.8%), amikacin (74.1%), erythromycin (85.2%), and azithromycin (85.2%). These results highlights the need for prudent use of specific antimicrobial agents in veterinary clinical treatment.


Assuntos
Infecções por Actinomycetales/veterinária , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Pneumonia Bacteriana/veterinária , Infecções por Actinomycetales/tratamento farmacológico , Infecções por Actinomycetales/microbiologia , Animais , Eritromicina/farmacologia , Testes de Sensibilidade Microbiana , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/microbiologia , Suínos , Virulência , Fatores de Virulência/genética
16.
Trop Anim Health Prod ; 51(4): 987-992, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30535896

RESUMO

Pasteurella multocida (P. multocida) is an important pathogen that causes bovine respiratory disease (BRD) in China and other countries. To investigate the antimicrobial susceptibility of P. multocida isolated from different provinces in China, we analyzed antimicrobial susceptibility phenotypes and pulsed-field gel electrophoresis (PFGE) types of P. multocida; then, we sequenced the complete genome of strain found to be multidrug-resistant. The isolates exhibited resistance to many antimicrobial agents, especially amikacin, sulfamethoxazole, sulfachloropyridazinesodium, macrolides, and fluoroquinolones. Pulsed-field gel electrophoresis analysis showed that a clonal spread of multidrug-resistant isolates occurred in various provinces. All of the isolates carried class I integron.


Assuntos
Anti-Infecciosos/farmacologia , Doenças dos Bovinos/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Pasteurella/veterinária , Pasteurella multocida/efeitos dos fármacos , Pasteurella multocida/genética , Animais , Bovinos , China , Genótipo , Testes de Sensibilidade Microbiana/veterinária , Tipagem Molecular/veterinária , Infecções por Pasteurella/microbiologia , Pasteurella multocida/isolamento & purificação , Fenótipo
17.
BMC Vet Res ; 13(1): 169, 2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28599670

RESUMO

BACKGROUND: In recent years, highly frequent swine respiratory diseases have been caused by extraintestinal pathogenic Escherichia coli (ExPEC) in China. Due to this increase in ExPECs, this bacterial pathogen has become a threat to the development of the Chinese swine industry. To investigate ExPEC pathogenesis, we isolated a strain (named SLPE) from lesioned porcine lungs from Changchun in China, reported the draft genome and performed comparative genomic analyses. RESULTS: Based on the gross post-mortem examination, bacterial isolation, animal regression test and 16S rRNA gene sequence analysis, the pathogenic bacteria was identified as an ExPEC. The SLPE draft genome was 4.9 Mb with a G + C content of 51.7%. The phylogenomic comparison indicated that the SLPE strain belongs to the B1 monophyletic phylogroups and that its closest relative is Avian Pathogenic Escherichia coli (APEC) O78. However, the distribution diagram of the pan-genome virulence genes demonstrated significant differences between SLPE and APEC078. We also identified a capsular polysaccharide synthesis gene cluster (CPS) in the SLPE strain genomes using blastp. CONCLUSIONS: We isolated the ExPEC (SLPE) from swine lungs in China, performed the whole genome sequencing and compared the sequence with other Escherichia coli (E. coli). The comparative genomic analysis revealed several genes including several virulence factors that are ExPEC strain-specific, such as fimbrial adhesins (papG II), ireA, pgtP, hlyF, the pix gene cluster and fecR for their further study. We found a CPS in the SLPE strain genomes for the first time, and this CPS is closely related to the CPS from Klebsiella pneumoniae.


Assuntos
Infecções por Escherichia coli/veterinária , Escherichia coli Extraintestinal Patogênica/genética , Genoma Bacteriano , Pneumonia Bacteriana/veterinária , Doenças dos Suínos/microbiologia , Animais , Cápsulas Bacterianas/metabolismo , China , DNA Bacteriano , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Escherichia coli Extraintestinal Patogênica/classificação , Escherichia coli Extraintestinal Patogênica/efeitos dos fármacos , Escherichia coli Extraintestinal Patogênica/isolamento & purificação , Fazendas , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Testes de Sensibilidade Microbiana , Família Multigênica , Filogenia , Pneumonia Bacteriana/microbiologia , Polissacarídeos Bacterianos/biossíntese , Análise de Sequência de DNA/veterinária , Sorotipagem , Suínos , Doenças dos Suínos/patologia , Virulência/genética
18.
J Electrocardiol ; 48(2): 241-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25601408

RESUMO

AIMS: To evaluate the relationships between ST-segment resolution (STR) and echocardiography-determined left ventricular (LV) global and regional function and deformation in the sub-acute phase of STEMI. METHODS AND RESULTS: STR, defined as either complete (≥70%) or incomplete (<70%), was evaluated 60minutes after primary percutaneous coronary intervention (PCI) of 84 STEMI patients. Conventional two-dimensional (2D) echocardiography and 2D speckle-tracking echocardiography (STE) were performed at 3-7days after reperfusion. LV deformation [including the infarction-related regional longitudinal (RLS), circumferential (RCS), and radial (RRS) strains, and global longitudinal (GLS), circumferential (GCS), and radial (GRS) strains] was measured by 2D STE. LV segmental function was assessed by wall motion score index (WMSI). Patients in incomplete vs. complete STR groups had higher WMSI (p<0.001); decreased peak amplitude of RLS (p<0.001), RCS (p=0.008), RRS (p=0.002); and decreased peak amplitude of GLS (p<0.001), GCS (p<0.001), GRS (p=0.003). RLS (r=0.27, p=0.015) and GLS (r=0.33, p=0.003) were best correlates of STR at the regional and global level, respectively. CONCLUSIONS: STR correlated with global and regional LV function and deformation in patients with sub-acute phase of STEMI after PCI. RLS and GLS were the strongest correlates of STR at the regional and global levels, respectively.


Assuntos
Ecocardiografia/métodos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/cirurgia , Reperfusão Miocárdica/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Angiografia Coronária , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea
19.
Heart Rhythm ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885753

RESUMO

BACKGROUND: The electrocardiogram-based algorithm for predicting para-septal atrial tachycardia (PSAT) is limited by the significant overlaps in the P-wave morphology originating from various para-septal sites. OBJECTIVE: The aim of this study was to investigate the endocardial activation characteristics of PSAT and to seek an endocardial activation-derived predictor for the ablation site. METHODS: Forty-four patients (11 males, average 62.6±14.7 years) with PSAT ablation in four tertiary medical centers were assigned into three groups according to the ablation site: right atrial (RA) para-Hisian region (Group 1, n=10), the noncoronary cusp (NCC) (Group 2, n=13) and left atrial (LA) para-septal areas (Group 3, n=21). Multiple-chamber activation mapping was performed guided by a 3D navigation system. The discrepancies in the earliest activation time between two of three chambers (ΔRA-LA, ΔRA-NCC and ΔLA-NCC) were calculated in each group and used for pairwise comparisons. RESULTS: There was significant difference in ΔRA-LA, ΔRA-NCC, and ΔLA-NCC compared among three groups. ΔRA-LA was the only parameter which could consistently predict the ablation site of PSAT with good accuracy (AUC 1.000, sensitivity 100%/ specificity 100%, and cut-off value 7ms for predicting right para-Hisian or NCC ablation; AUC 0.974, sensitivity 92.3%/specificity 95.2%, and cut-off value -4 ms for predicting NCC or left para-septal ablation). Based on two cut-off values, A two-step algorithm was developed to predict the ablation site of PSAT with positive predictive value of 95.4% and negative predictive value of 97.0%. CONCLUSIONS: ΔRA-LA is a useful endocardial activation-derived parameter for predicting the successful ablation site of PSAT.

20.
One Health ; 18: 100765, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855194

RESUMO

In recent years, aerosols have been recognized as a prominent medium for the transmission of antibiotic-resistant bacteria and genes. Among these, particles with a particle size of 2 µm (PM2.5) can directly penetrate the alveoli. However, the presence of antibiotic-resistant genes in aerosols from pet hospitals and the potential risks posed by antibiotic-resistant bacteria in these aerosols to humans and animals need to be investigated. In this study, cefotaxime-resistant bacteria were collected from 5 representative pet hospitals in Changchun using a Six-Stage Andersen Cascade Impactor. The distribution of bacteria in each stage was analyzed, and bacteria from stage 5 and 6 were isolated and identified. Minimal inhibitory concentrations of isolates against 12 antimicrobials were determined using broth microdilution method. Quantitative Polymerase Chain Reaction was employed to detect resistance genes and mobile genetic elements that could facilitate resistance spread. The results indicated that ARBs were enriched in stage 5 (1.1-2.1 µm) and stage 3 (3.3-4.7 µm) of the sampler. A total of 159 isolates were collected from stage 5 and 6. Among these isolates, the genera Enterococcus spp. (51%), Staphylococcus spp. (19%), and Bacillus spp. (14%) were the most prevalent. The isolates exhibited the highest resistance to tetracycline and the lowest resistance to cefquinome. Furthermore, 56 (73%) isolates were multidrug-resistant. Quantitative PCR revealed the expression of 165 genes in these isolates, with mobile genetic elements showing the highest expression levels. In conclusion, PM2.5 from pet hospitals harbor a significant number of antibiotic-resistant bacteria and carry mobile genetic elements, posing a potential risk for alveolar infections and the dissemination of antibiotic resistance genes.

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