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BackgroundEosinophilic meningitis (EM) is a rare clinical syndrome caused by both infectious and noninfectious diseases. In tropical pacific countries, Angiostrongylus cantonensis is the most common cause. However, the EM definition varies in the literature, and its relation to parasitic meningitis (PM) remains unclear.Methodology/principal findingsAdult and adolescent patients of 13 years old or above with suspected central nervous system (CNS) infections with abnormal CSF findings were prospectively enrolled at a tertiary referral hospital in Hanoi, Vietnam from June 2012 to May 2014. Patients with EM or suspected PM (EM/PM) were defined by the presence of either ≥10% eosinophils or an absolute eosinophil cell counts of ≥10/mm3 in the CSF or blood eosinophilia (>16% of WBCs) without CSF eosinophils. In total 679 patients were enrolled: 7 (1.03%) had ≥10% CSF eosinophilia, 20 (2.95%) had ≥10/mm3 CSF eosinophilia, and 7 (1.03%) had >16% blood eosinophilia. The patients with ≥10% CSF eosinophilia were significantly younger (p = 0.017), had a lower body temperature (p = 0.036) than patients with ≥10/mm3 CSF eosinophilia among whom bacterial pathogens were detected in 72.2% (13/18) of those who were tested by culture and/or PCR. In contrast, the characteristics of the patients with >16% blood eosinophilia resembled those of patients with ≥10% CSF eosinophilia. We further conducted serological tests and real-time PCR to identify A. cantonensis. Serology or real-time PCR was positive in 3 (42.8%) patients with ≥10% CSF eosinophilia and 6 (85.7%) patients with >16% blood eosinophilia without CSF eosinophils but none of patients with ≥10/mm3 CSF eosinophilia.ConclusionsThe etiology of PM in northern Vietnam is A. cantonensis. The eosinophil percentage is a more reliable predictor of parasitic EM than absolute eosinophil count in the CSF. Patients with PM may present with a high percentage of eosinophils in the peripheral blood but not in the CSF.

BACKGROUND:Scrub typhus (ST) is a leading cause of non-malarial febrile illness in Southeast Asia, but evidence of its true disease burden is limited because of difficulties of making the clinical diagnosis and lack of adequate diagnostic tests. To describe the epidemiology and clinical characteristics of ST, we conducted an observational study using multiple diagnostic assays at a national tertiary hospital in Hanoi, Vietnam. METHODOLOGY/PRINCIPAL FINDINGS:We enrolled 1,127 patients hospitalized with documented fever between June 2012 and May 2013. Overall, 33 (2.9%) patients were diagnosed with ST by PCR and/or screening of ELISA for immunoglobulin M (IgM) with confirmatory tests: 14 (42.4%) were confirmed by indirect immunoperoxidase assay (IIP), and 19 (57.6%) were by IIP and PCR. Living by farming, conjunctival injection, eschar, aspartate aminotransferase elevation, and alanine aminotransferase elevation were significantly associated with ST cases (adjusted odds ratios (aORs): 2.8, 3.07, 48.8, 3.51, and 4.13, respectively), and having a comorbidity and neutrophilia were significantly less common in ST cases (aORs: 0.29 and 0.27, respectively). The majority of the ST cases were not clinically diagnosed with rickettsiosis (72.7%). Dominant IIP reactions against a single antigen were identified in 15 ST cases, whereas indistinguishably high reactions against multiple antigens were seen in 11 ST cases. The most frequently observed dominant IIP reaction was against Karp antigen (eight cases) followed by Gilliam (four cases). The highest diagnostic accuracy of IgM ELISA in acute samples was 78%. In a phylogenetic analysis of the 56-kDa type-specific antigen gene, the majority (14 cases) were located in the Karp-related branch followed by the Gilliam-related (two cases), Kato-related (two cases), and TA763-related clades (one case). CONCLUSIONS/SIGNIFICANCE:Both the clinical and laboratory diagnoses of ST remain challenging at a tertiary hospital. Implementation of both serological and nucleic acid amplification assays covering endemic O. tsutsugamushi strains is essential.

Streptococcus pneumoniae is the major bacterial pathogen causing high pneumonia morbidity and mortality in children <5 years of age. This study aimed to determine the molecular epidemiology of S. pneumoniae detected among hospitalized pediatric ARI cases at Khanh Hoa General Hospital, Nha Trang, Vietnam, from October 2015 to September 2016 (pre-PCV). We performed semi-quantitative culture to isolate S. pneumoniae. Serotyping, antimicrobial susceptibility testing, resistance gene detection and multi-locus sequence typing were also performed. During the study period, 1300 cases were enrolled and 413 (31.8%) S. pneumoniae were isolated. School attendance, age <3 years old and prior antibiotic use before admission were positively associated with S. pneumoniae isolation. Major serotypes were 6A/B (35.9%), 19F (23.7%) and 23F (12.7%), which accounted for 80.3% of vaccine-type pneumococci. High resistance to Clarithromycin, Erythromycin and Clindamycin (86.7%, 85%, 78.2%) and the mutant drug-resistant genes pbp1A (98.1%), pbp2b (98.8%), pbp2x (99.6%) ermB (96.6%) and mefA (30.3%) were detected. MLST data showed high genetic diversity among the isolates with dominant ST 320 (21.2%) and ST 13223 (19.3%), which were mainly found in Vietnam. Non-typeables accounted for most of the new STs found in the study. Vaccine-type pneumococcus and macrolide resistance were commonly detected among hospitalized pediatric ARI cases. [ABSTRACT FROM AUTHOR]

Theimproving access to increasing amounts of biomedical data provides completely new chances for advanced patient stratification and disease subtyping strategies. This requires computational tools that produce uniformly robust results across highly heterogeneous molecular data. Unsupervised machine learning methodologies are able to discover de novo patterns in such data. Biclustering is especially suited by simultaneously identifying sample groups and corresponding feature sets across heterogeneous omics data. The performance of available biclustering algorithms heavily depends on individual parameterization and varies with their application. Here, we developedMoSBi (molecular signature identification using biclustering), an automated multialgorithm ensemble approach that integrates results utilizing an error model-supported similarity network. We systematically evaluated the performance of 11 available and established biclustering algorithms together with MoSBi. For this, we used transcriptomics, proteomics, and metabolomics data, as well as synthetic datasets covering various data properties. Profiting from multialgorithm integration, MoSBi identified robust group and diseasespecific signatures across all scenarios, overcoming single algorithm specificities. Furthermore, we developed a scalable network-based visualization of bicluster communities that supports biological hypothesis generation. MoSBi is available as an R package and web service to make automated biclustering analysis accessible for application in molecular sample stratification. [ABSTRACT FROM AUTHOR]

We study the anisotropic problem where pi ⩾ 2, Ω is a domain of , w is a nonnegative function and f is an increasing function. We prove that the problem has no nontrivial stable solution under various assumptions on pi, Ω, w and f. [ABSTRACT FROM AUTHOR]

Macroscopic (steady-state viscosity,density) and microscopic (NMRchemical shifts, 1H NMR relaxation times, and diffusion)properties of the 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc])−dimethylsulfoxide (DMSO) mixture were studied in detail as a function of DMSOmolar fraction at various temperatures. Temperature dependencies wereused to calculate the activation energies. NMR results indicate thatat low molar fraction of DMSO (<0.4), it weakly associates withthe cation and in doing so disrupts the strong ion–ion associationthat exists in the pure ionic liquid. Stokes–Einstein equation,which linearly correlates the diffusion coefficient of a sphericalmolecule and macroscopic viscosity, was shown to work well for the[EMIM][OAc]–DMSO mixture. The influence of DMSO on the “anomalous”diffusion in [EMIM][OAc] (“quick” cation vs “slow”anion) was investigated; it was demonstrated that DMSO makes the cationdiffusion slower. All parameters studied showed relatively small deviationsfrom the ideal mixing rule behavior (from 20% to 50% difference betweenexperimental and theoretically predicted results), confirming weakinteractions between the components. [ABSTRACT FROM AUTHOR]

To develop an appropriate programmatic response to the concentrated HIV epidemic, program managers require reliable estimates of the sizes of the key populations. This study attempts to estimate the population size of people who inject drugs (PWID) in Thai Nguyen-a province in the northern part of Vietnam. Two source capture-recapture population size estimates were calculated using data from two respondent driven sampling survey rounds conducted in 5 selected districts from May to August 2019. The population size of the PWID was calculated based on the number of PWID recruited in each survey and 'recaptured' during the first and the second survey. Additionally, personal network size data collected in the RDS was used to measure the population of PWID using the Successive Sampling Population Size Estimate (SS-PSE) method. The population of PWID estimated in five selected districts using the two capture-recapture method (CRC) (median = 5,396, 95% CI: 4,011-9,100) was slightly lower than estimated using SS-PSE with RDS survey 1 (median = 5,580, 95% CI: 3,024-9,272) and higher than when using SS-PSE with RDS survey 2 (median = 4,793; 95% CI: 2,310-8,618). The provincial PWID population estimates based on various approaches (e.g. extrapolation based on the prevalence of PWID in the districts) ranged from 6,498 (95% CI: 4,829-10,957) to around 6,807 (95% CI: 5,341-10,527). A provincial estimate of 6,782 PWID, with a confidence interval ranging from 5,312 to 10,527, will help guide planning and resource allocation to support appropriate levels of HIV prevention, care, and treatment services in the Thai Nguyen province., Competing Interests: The authors have declared that no competing interest exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

The viscosities of microcrystalline cellulose dissolved in 1-ethyl-3-methylimidazolium acetate (EMIMAc) and in 1-butyl-3-methylimidazolium chloride (BMIMCl) were studied in detail as a function of polymer concentration and temperature. The goal was to compare the flow of solutions, macromolecule hydrodynamic properties in each solvent, and the activation energies of viscous flow. Intrinsic viscosities were determined using the truncated form of the general Huggins equation. In both solvents cellulose intrinsic viscosity decreases with increasing temperature, indicating the decrease of solvent thermodynamic quality. The activation energies for both types of cellulose solutions were calculated. For cellulose-EMIMAc the Arrhenius plot showed a concave shape, and thus the Vogel-Tamman-Fulcher (VTF) approach was used. We suggest an improved method of data analysis for the determination of VTF constants and demonstrate that cellulose-EMIMAc solution viscosity obeys VTF formalism. Once the dependences of Arrhenius activation energy and VTF pseudo-activation energy were obtained for the whole range of concentrations studied, they were all shown to be described by a simple power-law function of polymer concentration.