Fluorescence nanosilica-based cell tracker has been explored and applied in cell biological research. However, the aggregation of these nanoparticles at physiological pH is still the main limitation. ...In this research, we introduced a novel fluorescence nano-based cell tracker suitable for application in live cells. The silica-coated fluorescein isothiocyanate isomer (FITC-SiO
) nanoparticles (NPs) were modified with carboxymethylsilanetriol disodium salt (FITC-SiO
-COOH), integrating the dianion form of FITC molecules. This nanosystem exhibited superior dispersion in aqueous solutions and effectively mitigated dye leakage. These labeled NPs displayed notable biocompatibility and minimal cytotoxicity in both in vitro and in vivo conditions. Significantly, the NPs did not have negative implications on cell migration or angiogenesis. They successfully penetrated primary fibroblasts, human umbilical vein endothelial cells and HeLa cells in both 2D and 3D cultures, with the fluorescence signal enduring for over 72 h. Furthermore, the NP signals were consistently observed in the developing gastrointestinal tract of live medaka fish larvae for extended periods during phases of subdued digestive activity, without manifesting any apparent acute toxicity. These results underscore the promising utility of FITC-SiO
-COOH NPs as advanced live cell trackers in biological research.
Abstract The first nationwide outbreak of COVID-19 in Vietnam started in late April 2021 and was caused almost exclusively by a single Delta lineage, AY.57. In early 2022, multiple Omicron variants ...co-circulated with Delta variants and quickly became dominant. The co-circulation of Delta and Omicron happened leading to possibility of co-infection and recombination events which can be revealed by viral genomic data. From January to October 2022, a total of 1028 viral RNA samples out of 4852 positive samples (Ct < 30) were sequenced by the long pooled amplicons method on Illumina platforms. All sequencing data was analysed by the workflow for SARS-CoV-2 on CLC genomics workbench and Illumina Dragen Covid application. Among those sequenced samples, we detected a case of Delta AY.57/Omicron BA.1 co-infection and two cases of infection with Delta AY.57/Omicron BA.2 recombinants which were nearly identical and had different epidemiological characteristics. Since the AY.57 lineage circulated almost exclusively in Vietnam, these results strongly suggest domestic events of co-infection and recombination. These findings highlight the strengths of genomic surveillance in monitoring the circulating variants in the community enabling rapid identification of viral changes that may affect viral properties and evolutionary events.
This study presents the modification of cassava root husk-derived biochar (CRHB) with ZnO nanoparticles (ZnO-NPs) for the simultaneous adsorption of As(
iii
), Cd(
ii
), Pb(
ii
) and Cr(
vi
). By ...conducting batch-mode experiments, it was concluded that 3% w/w was the best impregnation ratio for the modification of CRHB using ZnO-NPs, and was denoted as CRHB-ZnO3 in this study. The optimal conditions for heavy metal adsorption were obtained at a pH of 6-7, contact time of 60 min, and initial metal concentration of 80 mg L
−1
. The heavy metal adsorption capacities onto CRHB-ZnO3 showed the following tendency: Pb(
ii
) > Cd(
ii
) > As(
iii
) > Cr(
vi
). The total optimal adsorption capacity achieved in the adsorption of the 4 abovementioned metals reached 115.11 and 154.21 mg g
−1
for CRHB and CRHB-ZnO3, respectively. For each Pb(
ii
), Cd(
ii
), As(
iii
), and Cr(
vi
) metal, the maximum adsorption capacities of CRHB-ZnO3 were 44.27, 42.05, 39.52, and 28.37 mg g
−1
, respectively, and those of CRHB were 34.47, 32.33, 26.42 and 21.89 mg g
−1
, respectively. In terms of kinetics, both the pseudo-first-order and the pseudo-second-order fit well with metal adsorption onto biochars with a high correlation coefficient of
R
2
, while the best isothermal description followed the Langmuir model. As a result, the adsorption process of heavy metals onto biochars was chemisorption on homogeneous monolayers, which was mainly controlled by cation exchange and surface precipitation mechanisms due to enriched oxygen-containing surface groups with ZnO-NP modification of biochar. The FTIR and EDS analysis data confirmed the important role of oxygen-containing surface groups, which significantly contributed to removal of heavy metals with extremely high adsorption capacities, comparable with other studies. In conclusion, due to very high adsorption capacities for metal cations, the cassava root husk-derived biochar modified with ZnO-NPs can be applied as the alternative, inexpensive, non-toxic and highly effective adsorbent in the removal of various toxic cations.
This study presents the modification of cassava root husk-derived biochar (CRHB) with ZnO nanoparticles (ZnO-NPs) for the simultaneous adsorption of As(
iii
), Cd(
ii
), Pb(
ii
) and Cr(
vi
).
Herein, dual-emission carbon dots (DE-CDs) were synthesized using a one-pot hydrothermal method. DE-CDs exhibited two well-separated peaks at 433 and 513 nm under ultraviolet excitation. The prepared ...DE-CDs offer selective detection of Fe
3+
ions via inner filter effect (IFE) and Pb
2+
ions via aggregation-induced enhancement (AIE). The obtained DE-CDs showed a good affinity for both Fe
3+
and Pb
2+
ions in the presence of various interfering ions. The limits of detection were 0.797 ppm and 4.739 ppm for Pb
2+
and Fe
3+
, respectively. The finding reveals the huge potential of DE-CDs for the selective detection of multiple targets in one solution.
Graphical Abstract
Introduction
The outbreak of coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) had significant effects on the mental well-being in general, particularly for healthcare ...professionals. This study examined the prevalence of depression, anxiety, and stress, and identified the associated risk factors amongst healthcare workers during the COVID-19 outbreak in a tertiary hospital located in Vietnam.
Methods
We conducted a cross-sectional study at a tertiary-level hospital, where the Depression Anxiety and Stress Scale 21 (DASS-21) web-based questionnaire was employed. We analyzed the determinant factors by employing multivariate logistic models.
Results
The prevalence of depression, anxiety, and stress symptoms were 19.2%, 24.7%, and 13.9%, respectively. Factors such as engaging in shift work during the pandemic, taking care of patients with COVID-19, and staff’s health status were associated with mental health issues among health professionals. In addition, having alternate rest periods was likely to reduce the risk of stress.
Conclusion
The prevalence of mental health problems in healthcare workers during the COVID-19 pandemic was relatively high. Having resting periods could potentially mitigate the development of stress among health professionals. Our findings could be taken into account for improving mental health of the health professional population.
•31 carbapenem- and colistin-resistant K. pneumoniae underwent whole-genome sequencing.•Alterations in mgrB was the most common colistin resistance mechanism.•Mutations and insertion sequence ...transpositions disrupted mgrB functionality.
Resistance among Klebsiella pneumoniae to the last-resort antibiotics carbapenems and colistin is increasing worldwide. In this study, whole-genome sequencing was used to determine the colistin resistance mechanisms in clinical isolates of carbapenem- and colistin-resistant K. pneumoniae from Vietnam. Alterations in the regulatory gene mgrB, via mutations and insertion sequence transpositions, were found in 30 of 31 isolates, emphasising the importance of this resistance mechanism in colistin-resistant K. pneumoniae.
Obstructive sleep apnea (OSA) is the most common form of respiratory disorders during sleep in children, especially those with severe asthma. However, optimal treatment of asthma might significantly ...improve OSA severity.
It was a cohort study including children aged >5 years old and diagnosed with asthma according to GINA (Global Initiative for Asthma). The data related to age, gender, height, weight, body mass index (BMI), clinical symptoms and medical history of asthma, spirometry (FEV
: forced expiratory in 1 s), and exhaled nitric oxide (F
NO) were recorded for analysis. Respiratory polygraphy (RPG) was done for each study subject to diagnose OSA and its severity.
Among 139 asthmatic children, 99 patients with OSA (71.2%) were included in the present study (9.3 ± 0.2 years): 58.6% with uncontrolled asthma and 32.3% with partial controlled asthma. The mean ACT (asthma control testing) score was 19.0 ± 3.4. The most frequent night-time symptoms were restless sleep (76.8%), snoring (61.6%), sweating (52.5%), and trouble breathing during sleep (48.5%). The common daytime symptoms were irritable status (46.5%) and abnormal behavior (30.3%). The mean AHI (apnea-hypopnea index) was 3.5 ± 4.0 events/h. There was a significant correlation between BMI and snoring index (
= 0.189 and
= 0.027), bronchial and nasal F
NO with AHI (
= 0.046 and
< 0.001;
= 0.037 and
< 0.001; respectively). There was no significant correlation between asthma level, FEV
and AHI. The severity of asthma and respiratory function were improved significantly after 3 months and 6 months of asthma treatment in combination with leukotriene receptor antagonist (LRA) treatment. The symptoms related to OSA were significantly improved after treatment with LRA. The severity of OSA was decreased significantly after 3 months and 6 months of treatment.
The treatment of asthmatic children with comorbid OSA by LRA in combination with standard therapy for asthma could improve the control of asthma and the symptoms and severity of OSA.
Abstract
Chitinases are enzymes that catalyze the degradation of chitin, a major component of the cell walls of pathogenic fungi and cuticles of insects, gaining increasing attention for the control ...of fungal pathogens and insect pests. Production of recombinant chitinase in a suitable host can result in a more pure product with less processing time and a significantly larger yield than that produced by native microorganisms. The present study aimed to express the synthetic chi42 gene (syncodChi42), which was optimized from the chi42 gene of Trichoderma asperellum SH16, in Escherichia coli to produce 42 kDa chitinase (Ta-CHI42); then determined the activity of this enzyme, characterizations and in vitro antifungal activity as well as its immunogenicity in mice. The results showed that Ta-CHI42 was overexpressed in E. coli. Analysis of the colloidal chitin hydrolytic activity of purified Ta-CHI42 on an agar plate revealed that this enzyme was in a highly active form. This is a neutral chitinase with pH stability in a range of 6–8 and has an optimum temperature of 45°C with thermal stability in a range of 25–35°C. The chitinolytic activity of Ta-CHI42 was almost completely abolished by 5 mM Zn2+ or 1% SDS, whereas it remained about haft under the effect of 1 M urea, 1% Triton X-100 or 5 mM Cu2+. Except for ions such as Mn2+ and Ca2+ at 5 mM that have enhanced chitinolytic activity; 5 mM of Na+, Fe2+ or Mg2+ ions or 1 mM EDTA negatively impacted the enzyme. Ta-CHI42 at 60 U/mL concentration strongly inhibited the growth of the pathogenic fungus Aspergillus niger. Analysis of western blot indicated that the polyclonal antibody against Ta-CHI42 was greatly produced in mice. It can be used to analyze the expression of the syncodChi42 gene in transgenic plants, through immunoblotting assays, for resistance to pathogenic fungi.
This study aims to express the synthetic chi42 gene encodes 42 kDa chitinase of T. asperellum in E. coli, determine the enzyme characterizations, antifungal activity and its immunogenesis in the mouse.
PDF
