Development of quenching and washing protocols for quantitative intracellular metabolite analysis of uninfected and baculovirus-infected insect cells

Metabolomics refer to the global analysis of small molecule metabolites in a biological system, and can be a powerful tool to elucidate and optimize cellular processes, particularly when integrated into a systems biology framework. Determining the endometabolome in cultured animal cells is especially challenging, due to the conflicting demands for rapid quenching of metabolism and retention of membrane integrity, while cells are separated from the complex medium. The challenge is magnified in virus infected cells due to increased membrane fragility. This paper describes an effective methodology for quantitative intracellular metabolite analysis of the baculovirus-insect cell expression system, an important platform for the production of heterologous proteins and baculovirus-based biopesticides. These two applications were represented by Spodoptera frugiperda (Sf9) and Helicoverpa zea (HzAM1) cells infected with recombinant Autographa californica and wild-type Helicoverpa armigera nucleopolyhedroviruses (AcMNPV and HaSNPV), respectively. Specifically, an ice-cold quenching solution comprising 1.1% w/v NaCl and 0.2% w/v Pluronic® F-68 (NaCl + P) was found to be efficacious in preserving cell viability and minimizing cell leakage during quenching and centrifugation-based washing procedures (prior to extraction using cold 50% v/v acetonitrile). Good recoveries of intracellular adenosine triphosphate, total adenosine phosphates and amino acids were obtained after just one wash step, for both uninfected and infected insect cells. The ability to implement wash steps is critical, as insect cell media are metabolites-rich, while infected insect cells are much more fragile than their uninfected counterparts. Hence, a promising methodology has been developed to facilitate endometabolomic analysis of insect cell-baculovirus systems for bioprocess optimization

Child Melioidosis Deaths Caused by Burkholderia pseudomallei–Contaminated Borehole Water, Vietnam, 2019

Within 8 months, 3 children from 1 family in northern Vietnam died from melioidosis. Burkholderia pseudomallei of the same sequence type, 541, was isolated from clinical samples, borehole water, and garden and rice field soil. Boreholes should be properly constructed and maintained to avoid B. pseudomallei contamination

Estimating mental distress in Vietnam: the use of the SRQ-20

Background: Community-based estimates of psychopathology prevalence in developing countries such as Vietnam, are needed to reduce presumed significant burden of poor mental health. Aims: This study derived population-based prevalence estimates of mental distress, as measured by the SRQ-20, in a community sample of 4,981 adults living in Vietnam. This study also examined correlates of mental distress based on SRQ-20 caseness indications. Risk and protective factors were identified in terms of their unique contribution to caseness. Results: Using a cut-off of 7/8, 19.2% of the sample was considered to be a probable case (n = 954), with females endorsing more items than males. Marital status and employment status were not associated with mental health distress. Higher wealth, endorsing religious affi liation, and self-reports of good health were associated with lower SRQ-20 scores. Age and being female were associated with higher SRQ-20 scores. Conclusions: A single item was as adequate a measure of wealth as multi-item rating scales. Our estimate of mental distress using the SRQ-20 is much greater than that of other studies, and in contrast to western prevalence studies, age was not a protective factor in this study. The SRQ-20 is a brief, cost-effective and reasonably valid measure of both community and individual mental distress

High prevalence of colonisation with carbapenem-resistant Enterobacteriaceae among patients admitted to Vietnamese hospitals : Risk factors and burden of disease

Background Carbapenem-resistant Enterobacteriaceae (CRE) is an increasing problem worldwide, but particularly problematic in low- and middle-income countries (LMIC) due to limitations of resources for surveillance of CRE and infection prevention and control (IPC). Methods A point prevalence survey (PPS) with screening for colonisation with CRE was conducted on 2233 patients admitted to neonatal, paediatric and adult care at 12 Vietnamese hospitals located in northern, central and southern Vietnam during 2017 and 2018. CRE colonisation was determined by culturing of faecal specimens on selective agar for CRE. Risk factors for CRE colonisation were evaluated. A CRE admission and discharge screening sub-study was conducted among one of the most vulnerable patient groups; infants treated at an 80-bed Neonatal ICU from March throughout June 2017 to assess CRE acquisition, hospital-acquired infection (HAI) and treatment outcome. Results A total of 1165 (52%) patients were colonised with CRE, most commonly Klebsiella pneumoniae (n=805), Escherichia coli (n=682) and Enterobacter spp. (n=61). Duration of hospital stay, HAI and treatment with a carbapenem were independent risk factors for CRE colonisation. The PPS showed that the prevalence of CRE colonisation increased on average 4.2 % per day and mean CRE colonisation rates increased from 13% on the day of admission to 89% at day 15 of hospital stay. At the NICU CRE colonisation increased from 32% at admission to 87% at discharge, mortality was significantly associated (OR 5•5, P &lt; 0•01) with CRE colonisation and HAI on admission. Conclusion These data indicate that there is an epidemic spread of CRE in Vietnamese hospitals with rapid transmission to hospitalised patients.Funding agencies: Karolinska Institute, Solna, Sweden; Linkoping University, County of Ostergotland, Sweden; Swedish Foundation for International Cooperation in Research and Higher Education, STINT, Stockholm, Sweden; European Union, Marie Slodowska Curie Grants; ReAct, Up</p