Search

Introduction. Little is known about the epidemiology of Enterobacter cloacae strains producing a carbapenemase or metallo-beta-lactamase in Vietnamese hospitals. Aim. This study analysed E. cloacae strains resistant to imipenem or meropenem that had been isolated from patients admitted to one of the largest hospitals in Vietnam in 2014-2017. Methodology. Eighteen Vietnamese (VN) strains were subjected to whole-genome sequencing and their sequences compared with those of 17 E. cloacae strains carrying a carbapenemase or metallo-beta-lactamase in the database (db strains). Results. Although the distribution of virulence factors did not differ significantly between VN and db strains, all 18 VN isolates harboured blaNDM-1 , phylogenetic analysis revealed a high clonality of the VN strains. Bayesian phylogenetic analysis suggested that the VN strains speciated relatively recently. Conclusions. Several prevalent clones of carbapenem-resistant E. cloacae have circulated within Vietnamese hospitals. Adequate measures are needed to prevent their further spread. more...

Background: Long-term monitoring data is helpful to understand the fluctuation of susceptibility and pattern of cross resistance in insecticide resistance management. After the occurrence of imidacloprid resistance, the brown planthopper (BPH) has gradually developed resistance to thiamethoxam and clothianidin since 2010, but not to dinotefuran and nitenpyram. Here, we analyzed susceptibilities data of five neonicotinoids during 2005-2017 in East Asia and Vietnam to conduct cross-resistance patterns among neonicotinoids. To determine the factors of development of cross resistance in laboratory bioassays, we used the imidacloprid resistant and control strains that were selected from filed populations in the Philippines and Vietnam., Results: The Linear Mixed Models (LMM) analyses of insecticide susceptibility data showed that the slope values of imidacloprid resistance effects were 0.68 and 1.09 for resistance to thiamethoxam and clothianidin, respectively. Laboratory bioassay results showed that the LD 50 values for thiamethoxam and clothianidin in resistant strains (1.4-5.5 μg g -1 ) were 3.2-16.4 times higher than those in the control strains (0.28-1.5 μg g -1 ). However, the increase in the LD 50 values for imidacloprid was not related to that for dinotefuran and nitenpyram based on the results of the LMM analysis and laboratory bioassay., Conclusion: Our results demonstrate that the development of imidacloprid resistance result in strong-cross resistance to some neonicotinoids, thiamethoxam and clothianidin, but not to others, dinotefuran and nitenpyram. We anticipate that our findings will be a starting point for understanding mechanism of the different trend of cross resistance by analyzing long-term susceptibility data and laboratory bioassays in insect pests. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.) more...

Background: The two rice planthoppers, Nilaparvata lugens and Sogatella furcifera, have different life cycles in the regions of East Asia, the Red River Delta, and the Mekong Delta. The susceptibilities of these species to a range of insecticides have not previously been compared among the three regions over multiple years. Here, we describe the differences and similarities in insecticide susceptibilities of the two species among the three regions in 2006-2011., Results: In all three regions in 2006 - 2011, N. lugens developed high and moderate levels of resistance to imidacloprid and thiamethoxam, respectively, but this species did not develop resistance to fipronil. In contrast, S. furcifera developed a high level of resistance to fipronil. The ranges in 50% lethal dose (LD 50 ) values for N. lugens treated with both imidacloprid and thiamethoxam were similar over time between East Asia and the Red River Delta, and were different in the Mekong Delta., Conclusion: The results support the idea that resistant populations migrate from the Red River Delta region to East Asia. Therefore, continuous monitoring of the susceptibility of N. lugens to insecticides in the Red River Delta is very important for insecticide resistance management in East Asia. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.) more...

We present a novel and highly efficient method for exfoliating of graphite to produce graphene via the synergistic effects of in-situ plasma induced electrochemical exfoliation with ultrasonic energy, called ultrasonic-assisted cathodic electrochemical discharge. This method can work at moderate temperatures without the need of acidic media or expensive ionic electrolyte. The produced graphene exhibited a large lateral dimension of approximately 6μm and a thickness of 2.5nm, corresponding to approximately seven layers of graphene. An exfoliating mechanism of graphite to produce graphene sheets is also proposed in this study., (Copyright © 2016 Elsevier B.V. All rights reserved.) more...

Background: The influenza virus is one of the most critical threats to public health with major economic impact. Though annual influenza vaccination is currently the most effective prevention strategy against flu epidemics and pandemics, the mutational evolution of the influenza virus tends to reduce the effectiveness of strain-specific vaccines., Methods: For past decades, a broad spectrum of potentially universal influenza vaccines has been thoroughly investigated to suppress different strains and subtypes of influenza virus concomitantly. Universal influenza vaccines were attempted to be designed to target conserved regions of surface receptors to provide the necessary preventive strategy against new influenza outbreaks., Conclusions: Notably, the influenza hemagglutinin (HA) receptor has evolutionary conserved domains that can serve as basis for the rational design of a universal influenza vaccine. In this review, we examine recent studies on HA-based universal influenza vaccines and address their molecular mechanism. more...

Background: Despite the increasing prevalence of type 2 diabetes in urban areas, relatively little has been known about its actual prevalence and its associations in rural areas, Vietnam. The purpose of this study was to evaluate the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), diabetes and their risk factors in a rural province, Vietnam., Methods: A cross-sectional study with a representative sample was designed to estimate the hyperglycemia prevalence, using 75-g oral glucose tolerance test. Potential risk factors for hyperglycemia were analyzed using multinomial logistic regression, taken into account influences of socio-economic status, anthropometric measures, and lifestyle-related factors., Results: The age and sex-adjusted prevalence rates (95% CI) of isolated IFG, isolated IGT, combined IFG-IGT, and diabetes were 8.7 (7.0-10.5), 4.3 (3.2-5.4), 1.6 (0.9-2.3), and 3.7% (2.7-4.7%), respectively. There were still 73% of diabetic subjects without knowing the condition. Blood pressure, family history of diabetes, obesity-related measures (waist circumference, waist-hip ratio, body fat percentage, and abdominal obesity) were the independent risk factors for hyperglycemia (IFG, IGT, and diabetes)., Conclusions: The prevalence of hyperglycemia in rural areas has not been as sharply increased as that reported in urban cities, Vietnam. Blood pressure and obesity-related measures were the most significant predictors for hyperglycemia level and they can be taken into account in building prognosis models to early detection of diabetes in rural Vietnamese populations. more...

Background: The Feet for Walking clubfoot project from Australia formally introduced the Ponseti technique in Vietnam in 2004 and is based at the Da Nang Orthopedic and Rehabilitation Centre in central Vietnam., Methods: We provide an initial overview of the management of infant clubfoot deformity using the nonsurgical Ponseti method., Results: Early indicators of the outcome of implementing this clubfoot project are largely positive but also require ongoing review. Further analyses of the use of the Ponseti method (or obstacles preventing the same) following training of personnel is underway., Conclusions: Recent research has improved and refined the technique that must now be both appreciated and incorporated by clinicians. This technique is used across the world in both developed and developing countries and is universally regarded as the best management method for clubfoot deformities. more...

Background: In 2003 the development of insecticide resistance against neonicotinoids in the brown planthopper (BPH), Nilaparvata lugens (Stål) (Homoptera: Delphacidae), was first observed in Thailand and has since been found in other Asian countries such as Vietnam, China and Japan. However, the LD(50) values of BPH and the whitebacked planthopper (WBPH), Sogatella furcifera (Horváth), against both neonicotinoid and phenylpyrazole insecticides have been poorly reported in many Asian countries., Results: The topical LD(50) values for imidacloprid in the BPH populations collected from East Asia (Japan, China, Taiwan) and Vietnam in 2006 were 4.3-24.2 microg g(-1) and were significantly higher than those collected from the Philippines (0.18-0.35 microg g(-1)). The BPH populations indicated a positive cross-resistance between imidacloprid and thiamethoxam. Almost all the WBPH populations from Japan, Taiwan, China, Vietnam and the Philippines had extremely large LD(50) values (19.7-239 microg g(-1) or more) for fipronil, except for several populations from the Philippines and China., Conclusion: Species-specific changes in insecticide susceptibility were found in Asian rice planthoppers (i.e. BPH for imidacloprid and WBPH for fipronil). Insecticide resistance in BPH against imidacloprid occurred in East Asia and Indochina, but not in the Philippines. In contrast, insecticide resistance in WBPH against fipronil occurred widely in East and South-east Asia., (Copyright (c) 2008 Society of Chemical Industry.) more...