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1.
J Antimicrob Chemother ; 79(1): 61-65, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37965874

RESUMEN

OBJECTIVES: To investigate the genetic context and transferability of the oxazolidinone resistance gene optrA in a Streptococcus parasuis isolate. METHODS: The optrA-carrying S. parasuis isolate SFJ45 was characterized by PCR, antimicrobial susceptibility testing, complete genome sequencing and bioinformatic analysis. The transferability of optrA was verified by conjugation, followed by SmaI-PFGE and Southern blotting. RESULTS: The S. parasuis isolate SFJ45 was positive for optrA, mef(A), msr(D), erm(B), tetAB(P)', tet(M), aadE, aphA3, catQ, dfrG and mdt(A), conferring an MDR phenotype. The optrA gene was flanked by ISS1N at both termini in the same orientation, representing a novel 8750 bp pseudo-compound transposon, organized as the ISS1N-hth-clb-4hp-optrA-2hp-ISS1N structure. The ISS1N-optrA-carrying transposon was further inserted within an integrative and conjugative element, ICESpsuSFJ45, at 3' end of the fda gene. Conjugative transfer of the ISS1N-optrA-carrying transposon with ICESpsuSFJ45 was observed from S. parasuis to Streptococcus suis at a frequency of (1.01 ± 3.12) × 10-7. CONCLUSIONS: ISS1N was found to be associated with optrA spreading for the first time. Integration of the ISS1N-optrA transposon within ICESpsuSFJ45 may lead to the co-selection of optrA with other antimicrobial resistance genes, contributing to its horizontal transfer from S. parasuis to clinically more important bacterial pathogens.


Asunto(s)
Antiinfecciosos , Streptococcus suis , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Antiinfecciosos/farmacología , Antibacterianos/farmacología
2.
Eur J Clin Pharmacol ; 80(2): 175-183, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37996536

RESUMEN

PURPOSE: The association between antidepressant use and the risk of seizures remains controversial. Therefore, this meta-analysis examined whether antidepressant use affects the risk of seizures. METHODS: To identify relevant observational studies, we conducted systematic searches in PubMed and Embase of studies published through May 2023. Random-effects models were used to estimate overall relative risk. RESULTS: Our meta-analysis included eight studies involving 1,709,878 individuals. Our results showed that selective serotonin reuptake inhibitors (SSRI) (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.32-1.66; P < 0.001) and selective noradrenalin reuptake inhibitors (SNRI) (OR 1.65, 95% CI 1.24-2.19; P = 0.001), but not tricyclic antidepressants (TCA) (OR 1.27, 95% CI 0.84-1.92; P = 0.249), were associated with an increased risk of seizures. Subgroup analyses revealed an OR of 2.35 (95% CI 1.7, 3.24; P < 0.001) among short-term (< 30 days) antidepressant users. CONCLUSIONS: The findings of this meta-analysis support an increased risk of seizures in new-generation antidepressant users, expanding previous knowledge by demonstrating a more pronounced risk in short-term users.


Asunto(s)
Antidepresivos , Inhibidores Selectivos de la Recaptación de Serotonina , Humanos , Antidepresivos/efectos adversos , Inhibidores Selectivos de la Recaptación de Serotonina/efectos adversos , Convulsiones/inducido químicamente , Convulsiones/epidemiología , Antidepresivos Tricíclicos/efectos adversos , Riesgo
3.
Chem Soc Rev ; 52(14): 4725-4754, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37382597

RESUMEN

The chemistry of polypyridyl Ru(II) and cyclometalated Ir(III) derivatives provides long-lasting interest to researchers due to the inherent advantage of their triplet states in a variety of photoactivities. The introduction of Ru(N^N)3 and Ir(C^N)2(X^N) modules into well-defined architectures extends the research areas of both photoactive metal complexes and network chemistry, generating a lot of new opportunities with interesting structural aesthetics and profound functional possibilities. The rapid development of research in integrating Ru(II) or Ir(III) metallotecons into the architectures has been apparent in recent years which makes this a fascinating subject for reviewing. This review focuses on the design and syntheses of Ru(N^N)3 and Ir(C^N)2(X^N) functionalized architectures of metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), metallasupramolecules, organic supramolecules and supramolecular organic frameworks (SOFs). Furthermore, the photocatalytic applications including the hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), photocatalytic oxidation and photoredox catalysis of organic transformation are also presented.

4.
Sensors (Basel) ; 24(6)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38544273

RESUMEN

Designed to meet the demands of AGV global optimal path planning and dynamic obstacle avoidance, this paper proposes a combination of an improved A* algorithm and dynamic window method fusion algorithm. Firstly, the heuristic function is dynamically weighted to reduce the search scope and improve the planning efficiency; secondly, a path-optimization method is introduced to eliminate redundant nodes and redundant turning points in the path; thirdly, combined with the improved A* algorithm and dynamic window method, the local dynamic obstacle avoidance in the global optimal path is realized. Finally, the effectiveness of the proposed method is verified by simulation experiments. According to the results of simulation analysis, the path-planning time of the improved A* algorithm is 26.3% shorter than the traditional A* algorithm, the search scope is 57.9% less, the path length is 7.2% shorter, the number of path nodes is 85.7% less, and the number of turning points is 71.4% less. The fusion algorithm can evade moving obstacles and unknown static obstacles in different map environments in real time along the global optimal path.

5.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38732884

RESUMEN

The performance of the tire has a very important impact on the safe driving of the car, and in the actual use of the tire, due to complex road conditions or use conditions, it will inevitably cause immeasurable wear, scratches and other damage. In order to effectively detect the damage existing in the key parts of the tire, a tire surface damage detection method based on image processing was proposed. In this method, the image of tire side is captured by camera first. Then, the collected images are preprocessed by optimizing the multi-scale bilateral filtering algorithm to enhance the detailed information of the damaged area, and the optimization effect is obvious. Thirdly, the image segmentation based on clustering algorithm is carried out. Finally, the Harris corner detection method is used to capture the "salt and pepper" corner of the target region, and the segmsegmed binary image is screened and matched based on histogram correlation, and the target region is finally obtained. The experimental results show that the similarity detection is accurate, and the damage area can meet the requirements of accurate identification.

6.
Altern Ther Health Med ; 29(6): 56-61, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37442190

RESUMEN

Objective: To investigate the effect of enhanced recovery after surgery-based respiratory function exercise in elderly lung cancer patients and its impact on postoperative functional recovery. Methods: A total of 109 elderly lung cancer patients admitted to our hospital between January 2020 and January 2021 were included in the study. The patients were randomly assigned to either the control group (n = 52), receiving conventional care, or the research group (n = 57), receiving enhanced recovery after surgery-based respiratory function exercise in addition to conventional care. Respiratory function, functional capacity, quality of life, and incidence of pulmonary complications were compared between the two groups before and after the intervention. Results: Following the intervention, the research group showed significant improvements in Forced Expiratory Volume in the first second, Forced Vital Capacity, and Forced Expiratory Volume in the first second/Forced Vital Capacity compared to the control group (P < .05). The research group also exhibited higher Barthel indices (indicating better functional capacity) and lower St George's Respiratory Questionnaire scores (indicating better quality of life) compared to the control group (P < .05). The incidence of pulmonary complications was significantly lower in the research group (5.26%) compared to the control group (21.15%) (P < .05). Conclusions: Enhanced recovery after surgery-based respiratory function exercise can improve respiratory function, promote postoperative functional recovery, enhance the quality of life, and reduce pulmonary complications in elderly lung cancer patients. These findings support its clinical application and wider adoption.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Neoplasias Pulmonares , Humanos , Anciano , Calidad de Vida , Neoplasias Pulmonares/cirugía , Volumen Espiratorio Forzado , Capacidad Vital
7.
J Asian Nat Prod Res ; 25(6): 571-580, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36125926

RESUMEN

A series of 4-(propargyloxy) benzenesulfonamide derivatives with different substituents on the benzene ring were synthesized and evaluated for their insecticidal activity. Some of the compounds showed good insecticidal activity against Mythimna separata, and the LC50 value of the most active compound B2.5 was 0.235 mg/ml. Ultrastructural changes in the midgut epithelial cells of Mythimna separata were observed using transmission electron microscopy, and severe structural damage was found in microvilli, mitochondria and rough endoplasmic reticulum. It indicates that the possible site of action of these benzenesulfonamides is the cytoplasmic membrane and endomembrane system of the midgut epithelial cells. The above provides a basis for the development of novel insecticidal active compounds with a novel mechanism of action.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Animales , Larva , Insecticidas/farmacología , Mariposas Nocturnas/ultraestructura , Estructura Molecular , Bencenosulfonamidas
8.
Sensors (Basel) ; 22(15)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35898043

RESUMEN

According to the characteristics of rail defects, a rail microcrack detection method based on magnetoacoustic coupling effect is proposed in this paper. Firstly, the basic principle of a rail microcrack detection method based on magnetoacoustic coupling effect is described, and then the model is analyzed theoretically. Through simulation calculation, the current density distribution and Lorentz force distribution generated by electromagnetic excitation, the motion characteristics of particles under Lorentz force and the sound field distribution characteristics of magnetoacoustic signals generated by Lorentz force are obtained. Finally, an experimental platform was set up and the steel ring model was preliminarily tested. The magnetic and acoustic signals of the two steel ring boundaries excited by an electromagnetic field were collected. These signals correspond to the position distribution of the steel ring. The state change of rail microstructure will cause a change in the conductivity characteristics of rail materials, and will affect the characteristics and distribution of sound pressure in the detection. Therefore, the detection method based on the magnetoacoustic coupling effect can detect the surface microcracks of high-speed rail. This method has great feasibility and development potential in the field of rail flaw detection.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Tomografía , Acústica , Simulación por Computador , Interpretación de Imagen Asistida por Computador/métodos , Acero , Tomografía/métodos
9.
Sensors (Basel) ; 22(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502047

RESUMEN

Traffic sign detection is an essential component of an intelligent transportation system, since it provides critical road traffic data for vehicle decision-making and control. To solve the challenges of small traffic signs, inconspicuous characteristics, and low detection accuracy, a traffic sign recognition method based on improved (You Only Look Once v3) YOLOv3 is proposed. The spatial pyramid pooling structure is fused into the YOLOv3 network structure to achieve the fusion of local features and global features, and the fourth feature prediction scale of 152 × 152 size is introduced to make full use of the shallow features in the network to predict small targets. Furthermore, the bounding box regression is more stable when the distance-IoU (DIoU) loss is used, which takes into account the distance between the target and anchor, the overlap rate, and the scale. The Tsinghua-Tencent 100K (TT100K) traffic sign dataset's 12 anchors are recalculated using the K-means clustering algorithm, while the dataset is balanced and expanded to address the problem of an uneven number of target classes in the TT100K dataset. The algorithm is compared to YOLOv3 and other commonly used target detection algorithms, and the results show that the improved YOLOv3 algorithm achieves a mean average precision (mAP) of 77.3%, which is 8.4% higher than YOLOv3, especially in small target detection, where the mAP is improved by 10.5%, greatly improving the accuracy of the detection network while keeping the real-time performance as high as possible. The detection network's accuracy is substantially enhanced while keeping the network's real-time performance as high as possible.


Asunto(s)
Algoritmos , Reconocimiento en Psicología , Análisis por Conglomerados , Transportes , Inteligencia
10.
J Asian Nat Prod Res ; 24(4): 361-370, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34042537

RESUMEN

In our previous studies, a kind of novel benzenesulfonamides was found to be a candidate insecticidal compounds. It was shown that propargyloxy and sulfonamide groups are pharmacodynamic groups. One hundred and twenty-six (126) naphthalenesulfonamides derivatives with propargyloxy functionality were designed and synthesized, and their insecticidal activities were determined. Some of them showed outstanding activity, with LC50 values as low as 0.202 mg ml-1, much lower than that of the positive control celangulin V (23.9 mg ml-1). In addition, the structure-activity relationships were discussed, and molecular docking was used to verify the binding mode of the compound and the target receptor.


Asunto(s)
Insecticidas , Diseño de Fármacos , Insecticidas/farmacología , Simulación del Acoplamiento Molecular , Estructura Molecular , Naftalenos/farmacología , Relación Estructura-Actividad , Sulfonamidas/farmacología
11.
Psychol Health Med ; 27(3): 698-706, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34758658

RESUMEN

The rapid development of the coronavirus disease 2019 (COVID-19) outbreak has brought great harm to physical and mental health of the public. This study aims to investigate the psychological status and sleep quality of the Chinese public during the outbreak of the COVID-19 and its related factors. The survey was conducted from February 17th to February 26th, 2020 in southwestern China. The snowball sampling method was used to invite subjects. Demographic data were collected, and mental status and sleep quality were assessed by the Generalized Anxiety Disorder-7 Scale (GAD-7), the Patient Health Questionnaire-9 (PHQ-9), and the Pittsburgh Sleep Quality Index (PSQI). Descriptive, univariate, and correlation analyses were used to investigate risk factors for psychological status and sleep patterns. A total of 1509 adults (713 males and 796 females) were enrolled in this study. The overall prevalence of anxiety, depression, and decreased sleep quality were 22.3%, 32.2% and 35.4%, respectively. Compared with females, male population has witnessed a higher prevalence of anxiety symptoms (25.1% vs 20.4%, P= 0.007) and depressive symptoms (34.6% vs 30.0%, P= 0.027). In addition, age, marital status, living situation, involvement in anti-pandemic work, basic health status and work status were significant risk factors for anxiety or depression (P< 0.05). During the COVID-19 outbreak, psychological problems and sleep disorders were prevalent among the Chinese public. More attention should be paid to males, the elderly, the solitary, the unemployed, front-line workers in pandemic prevention, and patients with chronic diseases.


Asunto(s)
COVID-19 , Trastornos del Sueño-Vigilia , Adulto , Anciano , Ansiedad/epidemiología , Ansiedad/psicología , Trastornos de Ansiedad/epidemiología , COVID-19/epidemiología , China/epidemiología , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Brotes de Enfermedades , Femenino , Humanos , Internet , Masculino , Prevalencia , Factores de Riesgo , SARS-CoV-2 , Trastornos del Sueño-Vigilia/epidemiología , Encuestas y Cuestionarios
12.
Artículo en Inglés | MEDLINE | ID: mdl-33046498

RESUMEN

Tetracyclines are widely used in veterinary medicine and food animal production. Campylobacter members are major foodborne pathogens, and their resistance to tetracycline has been widely reported in different countries. To date, Tet(O), a ribosomal protection protein, is the only confirmed Tet resistance determinant in Campylobacter spp. Here, we reported the detection and characterization of a novel Tet resistance element in Campylobacter spp. of chicken origin. This gene is identified to be a variant of tet(L), which encodes an efflux pump for Tet resistance. The variant was detected in 14 of the 82 tetracycline-resistant Campylobacter isolates collected from chickens in Henan, China. Cloning of the tet(L) variant into tetracycline-susceptible Campylobacter jejuni NCTC 11168 confirmed its function in conferring resistance to tetracycline and doxycycline. In addition, this tet(L) variant elevated the MIC (4-fold increase) of tigecycline in the heterologous Escherichia coli host. Sequencing analysis indicated the tet(L) variant was located within a multidrug-resistance genomic island (MDRGI) containing tet(L) variant IS1216E-ORF1-fexA-Δtnp-IS1216E-tet(O)-tnpV-repA This MDRGI is inserted into conserved gene potB on the chromosome. Multilocus sequence type (MLST) analysis revealed that both clonal expansion and horizontal transfer were involved in the dissemination of the tet(L) variant. These findings reveal the emergence of a new Tet resistance determinant in Campylobacter spp., which may facilitate their adaptation to the antimicrobial selection pressure in chickens.


Asunto(s)
Campylobacter coli , Campylobacter jejuni , Campylobacter , Animales , Antibacterianos/farmacología , Campylobacter/genética , Campylobacter coli/genética , Campylobacter jejuni/genética , Pollos , China , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus
13.
Blood Purif ; 48(2): 175-182, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30485840

RESUMEN

BACKGROUND: The incidence of central venous catheter-related bloodstream infection (CRBSI) for continuous renal replacement therapy (CRRT) in kidney intensive care unit (ICU) patients is worthy of particular attention and recently, we analyzed clinical characteristics and risk factors of CRBSI for CRRT in our kidney ICU patients. METHODS: To be part of this retrospective study, 1,523 patients who had a central venous catheter (CVC) for CRRT during the period April 2010 to May 2015 in our centre were enrolled. The clinical features and pathogens of CRBSI patients were investigated. Patients who also had CRRT of kidney ICU hospitalization without CRBSI were enrolled in a 1: 2 ratio as control. Risk factors of the CRBSI were analyzed. RESULTS: A total of 57 patients had central venous CRBSI. The incidence of the infection was 3.7%. The mean rate of CRBSI was 3.9 per 1,000 catheter days, and the catheter median indwelling time was 14 (7-30) days. The most common pathogens were Gram-positive bacteria, which were noted in 29 cases (50.9%), followed by Gram-negative bacteria (36.8%). The most common pathogens causing CRBSI were Staphylococcus aureus (10 cases) and sewer enterobacteriaceae (10 cases) followed by Staphylococcus epidermidis (9 cases). CVC insertion sites included internal jugular vein (33 cases) and femoral vein (24 cases), accounting for 2.9% of internal jugular vein catheterization (1,140 cases) and 6.3% of femoral vein catheterization (383 cases) respectively. In total, 16, 20, 7 and 14 cases of CRBSI were noted in Spring, Summer, Autumn and Winter, accounting for 28.1, 35.1, 12.3 and 24.6% respectively. The most common infectious manifestations were chills (68.4%), fever (100%), and septic shock (49.1%). Multivariate analysis showed that catheterization of the femoral vein, long catheter indwelling time, low CD4+ lymphocytes and high acute physiology and chronic health evaluation (APACHE) II scores were independent factors associated with CRBSI. CONCLUSIONS: The incidence of CRBSI in our kidney ICU was 3.7%. Central venous CRBSI for CRRT was associated with catheterization of the femoral vein, long catheter indwelling time, compromised immune function and high APACHE II scores. Understanding pathogens and risk factors for central venous CRBSI in kidney ICU can help doctors prevent and treat CRBSI earlier.


Asunto(s)
Infecciones Relacionadas con Catéteres/etiología , Catéteres Venosos Centrales/efectos adversos , Terapia de Reemplazo Renal Continuo/efectos adversos , Adulto , Infecciones Relacionadas con Catéteres/sangre , Infecciones Relacionadas con Catéteres/microbiología , Cateterismo Venoso Central/efectos adversos , Femenino , Humanos , Incidencia , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
15.
Dalton Trans ; 52(48): 18133-18136, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37997776

RESUMEN

Anderson-type polyoxometalates have exhibited remarkable catalytic capabilities in a wide range of reactions. This discourse delves into the distinct categories of Anderson POMs and their respective catalytic reactions, which are examined in separate segments. These encompass the straightforward {XMo6} POMs, the organic grafting {XMo6} POMs, and the integration of POMs into POM cluster organic frameworks. It is important to highlight that specific catalytic functionalities can solely be accomplished via the utilization of Anderson-type POMs, thus emphasizing their indispensable role in future explorations.

16.
Front Neurol ; 14: 1176920, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37265460

RESUMEN

Background: Evidence suggests that there is an increased risk of stroke after herpes zoster (HZ). However, reports on the effects of HZ vaccination (HZV) and antiviral treatment on stroke risk are inconsistent. Thus, we examined these associations in a meta-analysis. Methods: To identify relevant studies, we searched three databases for articles published up to January 2023. Random-effect models were examined to determine overall pooled estimates and 95% confidence intervals (CIs). Results: This review included 12 observational studies (six on HZV and seven on antiviral treatment). When comparing vaccinated and unvaccinated patients, vaccination was found to be associated with a lower risk of stroke (OR, 0.78; 95% CI 0.68-0.9; P = 0.001). A meta-analysis of self-controlled case series (SCCS) revealed evidence of a reduced OR in individuals who received the vaccine (OR, 1.14; 95% CI 0.94-1.37; P = 0.181) compared with unvaccinated individuals (OR, 1.36; 95% CI 1.15-1.61; P < 0.001). Compared with untreated patients, antiviral therapy was not associated with a reduced risk of stroke (OR, 1.13; 95% CI 0.94-1.36; P = 0.201). The meta-analysis of the SCCS showed no evidence of a reduced OR in individuals who received antiviral therapy (OR, 1.33; 95% CI 1.17-1.51; P < 0.001) compared to untreated individuals (OR, 1.45; 95% CI 1.25-1.69; P < 0.001). Conclusions: This meta-analysis suggests that the HZV, but not antiviral treatment, decreases the odds of developing stroke.

17.
Front Vet Sci ; 9: 1002149, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36246313

RESUMEN

Tigecycline and carbapenems are last-resort antimicrobial agents to treat serious infections caused by multi-drug resistant bacterial pathogens. However, the co-occurrence of tigecycline and carbapenem resistance determinants challenges the clinical efficacy of these antimicrobial agents. In this study, we report the co-existence of tet(X4), bla NDM-1 and bla OXA-58 genes in the porcine Acinetobacter towneri isolate 19110F47. Sequence analysis revealed that tet(X4) gene, along with the florfenicol resistance gene floR, was flanked by three copies of IS91-like elements, which can form three different translocatable units (TUs), and were located in a 41,098-bp multidrug resistance region (MDRR) within a novel 100,354-bp genomic island (GI) region. TUs comprising floR-virD2-ISVsa3, hp-abh-tet(X4)-ISVsa3 and virD2-floR-ISVsa3-hp-abh-tet(X4)-ISVsa3 can be looped out from the chromosomal DNA and facilitate the transfer of the TU-based resistance genes into other plasmidic or chromosomal sites. In addition, the carbapenemase genes bla NDM-1 and bla OXA-58 were found on different non-conjugative multiresistance plasmids in this isolate, with the genetic contexts ISAba125-bla NDM-1-ble MBL-tnpR and ΔISAba3-bla OXA-58 -ISAba3, respectively. The simultaneous occurrence of tet(X4), bla NDM-1 and bla OXA-58 in the same porcine A. towneri isolate emphasizes the importance of antimicrobial resistance surveillance in food-producing animals.

18.
Pest Manag Sci ; 78(5): 1946-1952, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35085420

RESUMEN

BACKGROUND: Powdery mildew is one of the fungal diseases commonly occurring in the process of cucurbits protected and open cultivation. Cucumbers, melons and pumpkins are extremely susceptible. The secondary metabolites produced by plants are important sources of fungicides with low toxicity and environment-friendly characteristics. The aim of this study was to reveal the main active ingredient in the crude extracts of Disporopsis aspera rhizomes that inhibit cucurbits powdery mildew and evaluate its activities. RESULTS: In this study, the crude extracts of Disporopsis aspera rhizomes were found to exhibit excellent antifungal activity aganist Podosphaera xanthii, a causal agent of cucurbits powdery mildew. Based on the bioassay-guided method, l-azetidine-2-carboxylic acid (l-Aze) was isolated from this genus for the first time. l-Aze showed unique curative and eradicative activity against Podosphaera xanthii in vivo, which has never been reported before. Microscopic observation revealed that the curative spraying of l-Aze could effectively inhibit the mycelial growth, resulting in hollow parts of the mycelia, not forming conidiophores, and interrupting the life cycle of powdery mildew. The eradicative spraying of l-Aze caused the fracture of mycelia and deformity of conidiophores, which could not continue to produce conidia. CONCLUSION: l-Aze was the main active ingredient of D. aspera against Podosphaera xanthii, which had both curative and eradicative effects. The results provided a strong possibility of using the crude extracts of D. aspera rhizomes and its main effective component, l-Aze as biocontrol agents to control cucurbits powdery mildew.


Asunto(s)
Antifúngicos , Ácido Azetidinocarboxílico , Ascomicetos , Mezclas Complejas , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Rizoma
19.
Vet Microbiol ; 262: 109218, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34481222

RESUMEN

The emergence and rapid increase of carbapenem-resistant Enterobacteriaceae among food-producing animals poses a serious threat to public health. The aim of this study was to investigate the presence and dissemination of blaNDM-5 in porcine Klebsiella pneumoniae isolates. Of 19 meropenem-resistant K. pneumoniae isolates, 18 were blaNDM-5-positive and one carried blaNDM-1. Susceptibility testing indicated that all blaNDM-carrying K. pneumoniae showed a multiple drug resistance (MDR) profile. The blaNDM-5 gene was located on a conjugative IncX3 plasmid of ∼46-kb in all 18 blaNDM-5-carrying isolates. MLST analysis revealed that ST340 (n = 8), a member of the worldwide existing high-risk epidemic clonal group 258 (CG258), was predominant. Furthermore, whole genome sequence (WGS) analysis for one representative ST340 K. pneumoniae Kp19110124 showed a MDR profile for a wide range of antimicrobial agents, including meropenem, various cephalosporins, azteonam, gentamicin, ciprofloxacin, and florfenicol. Phylogenetic analysis exhibited that K. pneumoniae ST340 strains were clustered into one branch, which had spread across host species and across continents. Among them, K. pneumoniae Kp19110124 displayed a very close relationship with a clinical isolate collected from a patient in Canada. In conclusion, these results reveal the presence of a blaNDM-5-carrying conjugative IncX3 type plasmid into K. pneumoniae ST340 clone, which then may accelerate the dissemination of the blaNDM-5 gene in porcine K. pneumoniae isolates. The detection of high-risk blaNDM-5-carrying K. pneumoniae ST340 in food-producing animal poses a serious threat to public health.


Asunto(s)
Farmacorresistencia Bacteriana , Infecciones por Klebsiella , Klebsiella pneumoniae , Enfermedades de los Porcinos , beta-Lactamasas , Animales , Antibacterianos/farmacología , Células Clonales , Farmacorresistencia Bacteriana/genética , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/veterinaria , Klebsiella pneumoniae/clasificación , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana/veterinaria , Tipificación de Secuencias Multilocus/veterinaria , Filogenia , Plásmidos/genética , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , beta-Lactamasas/genética
20.
Front Microbiol ; 11: 1610, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32793144

RESUMEN

Carbapenems and tigecycline are two important classes of antimicrobial agents to treat the infections caused by Enterobacterales. Here, we reported a plasmid carrying both bla IMP-26 and tet(A) variant in clinical Klebsiella pneumoniae KP-1572. MIC results showed that K. pneumonia KP-1572 was resistant to a wide range of antimicrobials. The bla IMP-26 and tet(A) variant were located on an identical plasmid, which was indicated by S1-PFGE and southern blotting hybridization and can be successfully transferred by electroporation. Whole-plasmid sequencing and analysis revealed that a 142,993-bp-sized plasmid, designated pIMP1572, contains an IncFIIk backbone and a variable region harboring bla IMP-26 and tet(A) variant. The plasmid pIMP1572 was apparently originated from a tet(A)-carrying IncFIIk plasmid but with a deletion length of 6,216-bp and a multiple drug resistance region (MDRR) insertion of 25,259 bp. The plasmid pIMP1572 in the present study represents the first report of the IncFIIk plasmid co-carrying bla IMP and tet(A) variant, which should be monitored.

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