Shigella sonnei is a human-adapted pathogen that is emerging globally as the dominant agent of bacterial dysentery. To investigate local establishment, we sequenced the genomes of 263 Vietnamese S. ...sonnei isolated over 15 y. Our data show that S. sonnei was introduced into Vietnam in the 1980s and has undergone localized clonal expansion, punctuated by genomic fixation events through periodic selective sweeps. We uncover geographical spread, spatially restricted frontier populations, and convergent evolution through local gene pool sampling. This work provides a unique, high-resolution insight into the microevolution of a pioneering human pathogen during its establishment in a new host population.
The aim of the present study is to determine four anionic alkyl sulfate (AS) surfactants with different alkyl chains, namely, C8, C10, C12, and C14, in wastewater by CE with capacitively coupled ...contactless conductivity detection (CE‐C4D). The conditions effective for the separation of the four AS surfactants were systematically optimized and found to be in a Tris‐His (50 mM/20 mM) BGE solution at a pH of 8.95, using a separation voltage of +15 kV, hydrodynamic injection by siphoning using a 20 cm injection height and an injection time of 20 s. The LODs for C8, C10, C12, and C14 were 2.58, 2.30, 2.08, and 3.16 mg/L, respectively. The conditions used to achieve the simultaneous adsorption and preconcentration of the AS surfactants using Al2O3 beads were pH of 3 and 0.1 mM NaCl. The adsorption efficiencies were found to be 45.6, 50.8, 81.7, and 99.9%, while the desorption efficiencies reached 66.1, 70.4, 83.9, and 100.0% for C8, C10, C12, and C14, respectively. The concentrations of the AS surfactants in wastewater samples were quantified by CE‐C4D after preconcentration by simultaneous adsorption using Al2O3 beads. The results obtained from the proposed method were consistent with those obtained by HPLC‐MS/MS, with a deviation of less than 15%. Our results indicate that the CE‐C4D performed after preconcentration by an adsorption technique using Al2O3 beads is a new, inexpensive, and suitable method for quantifying AS surfactants in wastewater samples.
The effect of dietary supplementation of Flammulina velutipes concentrated extract (CE) on catfish fillet quality under cool preservation was evaluated. The catfish were fed by feed supplementing ...with 0% to 15% CE during the growth phase. After 30 days, the fish were filleted and stored at 4 ± 0.2°C for 7 days. The results showed that with 10% CE, the fish produced the best growth performance from 605 to 1106 g, corresponding to the lowest disease rate of 1.5%. Ergothioneine in muscle reached the highest value at 20.63 ± 1.35 mg/Kg. During the preservation, ergothioneine, 2,2-Diphenyl-2-picrylhydrazyl (DPPH) and lipid decreased slightly while free fatty acid (FFA) increased gradually until day 7. Peroxide and thiobarbituric acid reactive substances increased slowly after 7 days to 0.90 and 0.55 mg/Kg MDA, respectively. The b* value and total color variation (∆E) showed the slowest increase of −0.21 ± 0.67 and 46.85 ± 0.97, respectively, while the a* value decreased gradually during storage. pH decreased slightly on day 1, then increased to 6.4 ± 0.2 on day 7. The fillet was firmer on day 1, then decreased gradually in all treatments. Therefore, an increasing ergothioneine in catfish muscle leads to higher growth performance with a low disease rate and helps to prevent lipid oxidation, improving color and structural stability.
Abstract
α-Thalassemia is a common inherited blood disorder manifested mainly by the deletions of α-globin genes. In geographical areas with high carrier frequencies, screening of α-thalassemia ...carrier state is therefore of vital importance. This study presents a novel method for identifying female carriers of common α-thalassemia deletions using samples routinely taken for non-invasive prenatal tests for screening of fetal chromosomal aneuploidies. A total of 68,885 Vietnamese pregnant women were recruited and α-thalassemia statuses were determined by gap-PCR, revealing 5344 women (7.76%) carried deletions including αα/−−
SEA
(4.066%), αα/−α
3.7
(2.934%), αα/−α
4.2
(0.656%), and rare genotypes (0.102%). A two-stage model was built to predict these α-thalassemia deletions from targeted sequencing of the HBA gene cluster on maternal cfDNA. Our method achieved F1-scores of 97.14–99.55% for detecting the three common genotypes and 94.74% for detecting rare genotypes (−α
3.7
/−α
4.2
, αα/−−
THAI
, −α
3.7
/−−
SEA
, −α
4.2
/−−
SEA
). Additionally, the positive predictive values were 100.00% for αα/αα, 99.29% for αα/−−
SEA
, 94.87% for αα/−α
3.7
, and 96.51% for αα/−α
4.2
; and the negative predictive values were 97.63%, 99.99%, 99.99%, and 100.00%, respectively. As NIPT is increasingly adopted for pregnant women, utilizing cfDNA from NIPT to detect maternal carriers of common α-thalassemia deletions will be cost-effective and expand the benefits of NIPT.
We performed a prospective multicenter study to address the lack of data on the etiology, clinical and demographic features of hospitalized pediatric diarrhea in Ho Chi Minh City (HCMC), Vietnam. ...Over 2,000 (1,419 symptomatic and 609 non-diarrheal control) children were enrolled in three hospitals over a 1-year period in 2009-2010. Aiming to detect a panel of pathogens, we identified a known diarrheal pathogen in stool samples from 1,067/1,419 (75.2%) children with diarrhea and from 81/609 (13.3%) children without diarrhea. Rotavirus predominated in the symptomatic children (664/1,419; 46.8%), followed by norovirus (293/1,419; 20.6%). The bacterial pathogens Salmonella, Campylobacter, and Shigella were cumulatively isolated from 204/1,419 (14.4%) diarrheal children and exhibited extensive antimicrobial resistance, most notably to fluoroquinolones and third-generation cephalosporins. We suggest renewed efforts in generation and implementation of policies to control the sale and prescription of antimicrobials to curb bacterial resistance and advise consideration of a subsidized rotavirus vaccination policy to limit the morbidity due to diarrheal disease in Vietnam.
Linagliptin is a highly specific, long‐acting inhibitor that is used as an orally administrable agent for type‐2 diabetes treatment. Because only the R‐enantiomer is of clinical use, we developed a ...capillary electrophoresis method for the determination of the enantiomeric impurity of this compound. Carboxymethyl‐β‐cyclodextrin was selected as the chiral selector for the separation of linagliptin enantiomers. Design of experiments and desirability functions were used for the analytical optimization, which was focused on understanding and improving the electrophoretic process. The effects of significant parameters (background electrolyte concentration and pH, cyclodextrin concentration, temperature, and voltage) were thoroughly investigated. The complete separation of linagliptin and its enantiomeric impurity with baseline resolution was achieved within 10 min on an uncoated fused‐silica capillary (50 μm inner diameter, 365 μm outer diameter, 64.5/56 cm in total/ effective length) maintained at 25°C, under an applied voltage of 28.0 kV. The background electrolyte contained 70 mM sodium acetate and 4.7 mM carboxymethyl‐β‐cyclodextrin, and the pH was adjusted to 6.10. The method was validated, and a limit of quantitation of 0.05% for the impurity was estimated.
The electrochemical behavior and sensing performance of an electrode modified with NiFe
2
O
4
(NFO), MoS
2
, and MoS
2
-NFO were thoroughly investigated using CV, EIS, DPV, and CA measurements, ...respectively. MoS
2
-NFO/SPE provided a higher sensing performance towards the detection of clenbuterol (CLB) than other proposed electrodes. After optimization of pH and accumulation time, the current response recorded at MoS
2
-NFO/SPE linearly increased with an increase of CLB concentration in the range from 1 to 50 μM, corresponding to a LOD of 0.471 μM. In the presence of an external magnetic field, there were positive impacts not only on mass transfer, ionic/charge diffusion, and absorption capacity but also on the electrocatalytic ability for redox reactions of CLB. As a result, the linear range was widened to 0.5-50 μM and the LOD value was about 0.161 μM. Furthermore, stability, repeatability, and selectivity were assessed, emphasizing their high practical applicability.
The electrochemical behavior and sensing performance of an electrode modified with NiFe
2
O
4
(NFO), MoS
2
, and MoS
2
-NFO were thoroughly investigated using CV, EIS, DPV, and CA measurements, respectively.
In this study, a catalyst derived from iron slag (Fe-S) was used for heterogeneous Fenton oxidation (H2O2/Fe-S) of paracetamol in aqueous solution; the conventional homogeneous Fenton reaction ...(H2O2/Fe2＋) was run in parallel for comparison. Degradation of paracetamol, in terms of chemical oxygen demand (COD) removal, was found strongly dependent on the solution pH, with the maximum efficiency obtained at pH 3 for both H2O2/Fe-S and H2O2/Fe2＋ systems. The efficacy of paracetamol degradation was also affected by the ratio (w/w) of hydrogen peroxide to iron, as the maxima degradation was observed at ratios of 1:2 and 2:1 for the heterogeneous and homogeneous Fenton, respectively. In addition, the degradation efficiency decreased when the initial paracetamol concentration increased from 100 mg/L to 500 mg/L. Kinetic experiments showed that degradation of paracetamol fitted a pseudo-first-order kinetic model well, as evidenced by the Kd values of the pseudo-first-order kinetic model that followed the same sequence as the degradation efficiency of paracetamol. Processes involved in the degradation of paracetamol by H2O2/Fe-S mainly included adsorption and oxidation; for latter, the presence of FeO, ZnO, and SiO2 in Fe-S constituent might enhance the decomposition of H2O2 and generate more *OH radicals. The *OH radical-mediated oxidation was confirmed by significant declines in the elimination of paracetamol when the system was subject to various radical-scavengers including t-butanol, chloride, and carbonate species.
Display omitted
•Fe2＋ and Fe-S were used as catalysts for homogeneous and heterogeneous Fenton.•The paracetamol degradation by H2O2/Fe2＋ and H2O2/Fe-S reached the highest at pH 3.•The Fe2＋ ions released from Fe-S enhanced the formation of *OH radicals.•The paracetamol degradation followed pseudo-first order kinetic model.•The paracetamol degradation mechanism in H2O2/Fe-S system involved both adsorption and oxidation.
Background
: Rotavirus (RoV) remains the leading cause of acute gastroenteritis in infants and children aged under five years in both high- and low-middle-income countries (LMICs). In LMICs, RoV ...infections are associated with substantial mortality. Two RoV vaccines (Rotarix and Rotateq) are widely available for use in infants, both of which have been shown to be highly efficacious in Europe and North America. However, for unknown reasons, these RoV vaccines have markedly lower efficacy in LMICs. We hypothesize that poor RoV vaccine efficacy across in certain regions may be associated with genetic heritability or gene expression in the human host.
Methods/design
:
We designed an open-label single-arm interventional trial with the Rotarix RoV vaccine to identify genetic and transcriptomic markers associated with generating a protective immune response against RoV. Overall, 1,000 infants will be recruited prior to Expanded Program on Immunization (EPI) vaccinations at two months of age and vaccinated with oral Rotarix vaccine at two and three months, after which the infants will be followed-up for diarrheal disease until 18 months of age. Blood sampling for genetics, transcriptomics, and immunological analysis will be conducted before each Rotarix vaccination, 2-3 days post-vaccination, and at each follow-up visit (i.e. 6, 12 and 18 months of age). Stool samples will be collected during each diarrheal episode to identify RoV infection. The primary outcome will be Rotarix vaccine failure events (i.e. symptomatic RoV infection despite vaccination), secondary outcomes will be antibody responses and genotypic characterization of the infection virus in Rotarix failure events.
Discussion
: This study will be the largest and best powered study of its kind to be conducted to date in infants, and will be critical for our understanding of RoV immunity, human genetics in the Vietnam population, and mechanisms determining RoV vaccine-mediated protection.
Registration:
ClinicalTrials.gov, ID:
NCT03587389
. Registered on 16 July 2018.
Background: The COVID-19 pandemic has affected people of all ages and backgrounds, but pregnant women are a particularly vulnerable group. They are at increased risk of severe illness and death from ...COVID-19, yet there is limited and conflicting data about the factors that contribute to mortality in this population. In this study, we sought to use machine learning (ML) to predict the possible factors associated with mortality in pregnant women with COVID-19. Methods: We collected data from a large cohort of pregnant women who had been diagnosed with COVID-19 at Hung Vuong Hospital. We included a range of demographic, clinical, and laboratory variables in our analysis, such as age, gestational age, comorbidities, symptoms, and laboratory test results. Our goal was to identify the critical factors that could be used to predict mortality in this vulnerable population. We applied several ML models and analyzed the results to determine the most useful predictors. Results: We analyzed a cohort of 550 pregnant women diagnosed with COVID-19, comprising 525 survivors and 25 deaths. Using ML algorithms, we identified key clinical and patient factors that correlated with mortality risk, such as infection severity, pulse rate, breathing patterns, SpO2 levels, rapid diagnostic tests, internal pathology, breathing difficulties, and changes in consciousness. Additionally, several medical test factors were found to be significant, including white blood cells, neutrophils, platelets, C-reactive protein (CRP), procalcitonin, and chest X-ray abnormalities. Our analysis revealed that the Gaussian Naive Bayes (NB) model was the most accurate, with an AUC score of 0.79, demonstrating its potential as a valuable tool for identifying high-risk patients. Conclusions: Our results suggest that the available data can capture the relationship between COVID-19 symptoms and mortality in pregnant women. More studies are needed to improve the accuracy and generalizability of models for predicting mortality risk in this population.
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