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This study introduces a highly efficient and straightforward method for synthesizing gold nanoparticles (AuNPs) within a glucosamine/alginate (GluN/Alg) nanocomposite via an ionotropic gelation mechanism in aqueous environment. The resulting nanocomposite, AuNPs@GluN/Alg, underwent thorough characterization using UV–vis, EDX, FTIR, SEM, TEM, SAED, and XRD analyses. The spherical AuNPs exhibited uniform size with an average diameter of 10.0 nm. The nanocomposites facilitated the recyclable reduction of organic dyes, including 2-nitrophenol, 4-nitrophenol, and methyl orange, employing NaBH4 as the reducing agent. Kinetic studies further underscored the potential of this nanocomposite as a versatile catalyst with promising applications across various industrial sectors.

Theragnostic platforms, which integrate therapeutic and diagnostic capabilities, have gained significant interest in drug research because of to their potential advantages. This study reports the development of a novel multifunctional nanoparticle carrier system based on poly(ᴅ,ʟ-lactic-co-glycolic acid) (PLGA) for the targeted delivery of the chemotherapeutic agent chlorambucil (CHL) and the imaging agent IR780. The approach in this study incorporates Pluronic F127-folate onto the PLGA nanoparticles, which enables targeted delivery to folate receptor-expressing cancer cells. The F127-folate@PLGA/CHL/IR780 nanoparticles were formulated using a nanoprecipitation technique, resulting in small size, high homogeneity, and negative surface charge. Importantly, the folate-targeted nanoparticles demonstrated enhanced uptake and cytotoxicity in folate receptor-positive cancer cell lines (MCF-7 and HepG-2) compared to folate receptor-negative cells (HEK 293). Additionally, the F127-folate@PLGA/CHL/IR780 nanoparticles exhibited a lower IC50 value against cancer cells than non-targeted F127@PLGA/CHL/IR780 nanoparticles. These findings suggest that the developed F127-folate@PLGA/CHL/IR780 nanoparticles hold promise as a theragnostic system for targeted cancer therapy and diagnosis, leveraging the advantages of PLGA, folate targeting, and the integration of therapeutic and imaging agents.

Theragnostics has become a popular term nowadays, since it enables both diagnosis and therapy at the same time while only using one carrier platform. Therefore, formulating a nanocarrier system that could serve as theragnostic agent by using simple techniques would be an advantage during production. In this project, we aimed to develop a nanocarrier that can be loaded with the chemotherapeutic medication chlorambucil and magnetic resonance imaging agents (e.g., iron oxide nanoparticles and near-infrared fluorophore IR780) for theragnostics. Poly(lactic-co-glycolic acid) was combined with the aforementioned ingredients to generate poly(vinyl alcohol)-based nanoparticles (NPs) using the single emulsion technique. Then the NPs were coated with F127 and F127-folate by simple incubation for five days. The nanoparticles have the hydrodynamic size of approx. 250 nm with negative charge. Similar to chlorambucil and IR780, iron oxide loadings were observed for all three kinds of NPs. The release of chlorambucil was quicker at pH 5.4 than at pH 7.4 at 37 °C. The F127@NPs and F127-folate@NPs demonstrated much greater cell uptake and toxicity up to 72 h after incubation. Our in vitro results of F127@NPs and F127-folate@NPs have demonstrated the ability of these systems to serve as medication and imaging agent carriers for cancer treatment and diagnostics, respectively.

We present the in situ synthesis of silver nanoparticles (AgNPs) through ionotropic gelation utilizing the biodegradable saccharides lactose (Lac) and alginate (Alg). The lactose reduced silver ions to form AgNPs. The crystallite structure of the nanocomposite AgNPs@Lac/Alg, with a mean size of 4–6 nm, was confirmed by analytical techniques. The nanocomposite exhibited high catalytic performance in degrading the pollutants methyl orange and rhodamine B. The antibacterial activity of the nanocomposite is pH-dependent, related to the alterations in surface properties of the nanocomposite at different pH values. At pH 6, the nanocomposite demonstrated the highest antibacterial activity. These findings suggest that this nanocomposite has the potential to be tailored for specific applications in environmental and medicinal treatments, making it a highly promising material.

The aim of this research is to investigate the influence of different functional groups of β-cyclodextrin (CD) in functionalizing gold nanoparticles. The functionalized nanoparticles are then utilized for loading the 5-fluorouracil (5-FU) drug and evaluating their in vitro anticancer activity. A two-step method was employed to synthesize Mono-6-(1,3-trimethylenediamine)-6-deoxy-β-cyclodextrin (TMACD), which was further utilized for fabricating gold nanoparticles (AuNPs) using ultrasound-assisted synthesis. To investigate effect of different functional groups of β-cyclodextrin (CD) on drug delivery efficiency, three cyclodextrin derivatives, namely β-cyclodextrin (5-FU@AuNPs/CD), 2-hydroxylpropyl-β-cyclodextrin (5-FU@AuNPs/HPCD), and TMACD (5-FU@AuNPs/TMACD) were utilized to load 5-FU. Among them, the nanocomposite AuNPs/TMACD exhibited the highest associate efficiency and loading efficiency which were confirmed by analytic techniques such as FTIR, PXRD, TEM. Moreover, the release behavior of 5-FU from the nanocomposites was investigated at pH 7.4, revealing that all AuNPs/CDs nanocomposites effectively protected the drug with a low release percentage ranging from 23.13% to 29.45%. Docking model analysis indicated that the 5-FU ligand formed six hydrogen bonds and interacted favorably with the HPCD molecule. In the in vitro cell viability assay, both nanocomposites, 5-FU@AuNPs/CD and 5-FU@AuNPs/TMACD, not only demonstrated effective anticancer activity against breast cancer cells (MCF-7) but also exhibited minimal toxicity towards normal cell lines. Remarkably, the results revealed that 5-FU@AuNPs/TMACD displayed the highest efficacy in suppressing the growth of the breast cancer cells. These findings highlight the considerable potential of amine-derivative cyclodextrin-capped AuNPs as exceptionally efficient carriers for anticancer drugs, offering promising applications in both diagnosis and therapy.

BackgroundDiarrheagenic Escherichia coli (DEC) is a group of bacterial pathogens that causes life-threatening diarrhea in children in developing countries. However, there is limited information on the characteristics of DEC isolated from patients in these countries. A detailed genomic analysis of 61 DEC-like isolates from infants with diarrhea was performed to clarify and share the characteristics of DEC prevalent in Vietnam.Principal findingsDEC was classified into 57 strains, including 33 enteroaggregative E. coli (EAEC) (54.1%), 20 enteropathogenic E. coli (EPEC) (32.8%), two enteroinvasive E. coli (EIEC) (3.3%), one enterotoxigenic E. coli (ETEC), and one ETEC/EIEC hybrid (1.6% each), and surprisingly into four Escherichia albertii strains (6.6%). Furthermore, several epidemic DEC clones showed an uncommon combination of pathotypes and serotypes, such as EAEC Og130:Hg27, EAEC OgGp9:Hg18, EAEC OgX13:H27, EPEC OgGp7:Hg16, and E. albertii EAOg1:HgUT. Genomic analysis also revealed the presence of various genes and mutations associated with antibiotic resistance in many isolates. Strains that demonstrate potential resistance to ciprofloxacin and ceftriaxone, drugs recommended for treating childhood diarrhea, accounted for 65.6% and 41%, respectively.SignificanceOur finding indicate that the routine use of these antibiotics has selected resistant DECs, resulting in a situation where these drugs do not provide in therapeutic effects for some patients. Bridging this gap requires continuous investigations and information sharing regarding the type and distribution of endemic DEC and E. albertii and their antibiotic resistance in different countries.

ABSTRACT: Objectives: Tigecycline resistance mediated by the mobile tigecycline-inactivating enzyme gene tet(X) in Gram-negative bacteria is an emerging concern for global public health. However, limited information is available on the distribution of tet(X) in the natural environment. In this study, we investigated the presence of tet(X) in environmental Gram-negative bacteria. Methods: A carbapenem- and tigecycline-resistant Shewanella xiamenensis isolate (NUITM-VS1) was obtained from an urban drainage in Hanoi, Vietnam, in March 2021. Whole-genome sequencing analysis was performed by long- and short-read sequencing, resulting in a complete genome sequence. Antimicrobial resistance genes (ARGs) in the genome were detected based on the custom ARG database, including all known tigecycline resistance genes. Results: Shewanella xiamenensis isolate NUITM-VS1 harboured the tet(X4) gene and the blaOXA-48 carbapenemase gene on the chromosome. tet(X4) was flanked by IS91 family transposase genes, suggesting that the acquisition of tet(X4) was mediated by this mobile gene element (MGE), whereas no MGE was found surrounding blaOXA-48, consistent with previous findings that blaOXA-48-like β-lactamase genes are species-specific intrinsic ARGs in Shewanella spp. Conclusion: To the best of our knowledge, this is the first report of a tet(X4)-harbouring Shewanella sp. isolate. Our results provide genetic evidence of the complexity of the dynamics of clinically important ARGs among bacteria in the water environment.

Summary: Analyzing the metabolic dependencies of tumor cells is vital for cancer diagnosis and treatment. Here, we describe a protocol for 13C-stable glucose and glutamine isotope tracing in mice HER2+ breast cancer brain metastatic lesions. We describe how to inject cancer cells intracardially to generate brain metastatic lesions in mice. We then detail how to perform 13C-stable isotope infusion in mice with established brain metastasis. Finally, we outline steps for sample collection, processing for metabolite extraction, and analyzing mass spectrometry data.For complete details on the use and execution of this protocol, please refer to Parida et al. (2022).

Treatment of Staphylococcus aureus biofilm infections using conventional antibiotic therapy is challenging as only doses that are sublethal to the biofilm can be administered safely to patients. A potential solution to this challenge is targeted drug delivery. In this study, we tailored an aptamer-targeted liposomal drug delivery system for accumulation and delivery of antibiotics locally in S. aureus biofilm. In our search for a suitable targeting ligand, we identified six DNA aptamers that bound to S. aureus cells in biofilms, and we demonstrated that one of these aptamers could facilitate accumulation of liposomes around S. aureus cells inside the biofilm. Aptamer-targeted liposomes encapsulating a combination of vancomycin and rifampicin were able to eradicate S. aureus biofilm upon 24 h of treatment in vitro. Our results point to that aptamer-targeted drug delivery of antibiotics is a potential new strategy for treatment of S. aureus biofilm infections.

MAP estimation plays an important role in many probabilistic models. However, in many cases, the MAP problem is non-convex and intractable. In this work, we propose a novel algorithm, called BOPE, which uses Bernoulli randomness for Online Maximum a Posteriori Estimation. We show that BOPE has a fast convergence rate. In particular, BOPE implicitly employs a prior which plays as regularization. Such a prior is different from the one of the MAP problem and will be vanishing as BOPE does more iterations. This property of BOPE is significant and enables to reduce severe overfitting for probabilistic models in ill-posed cases, including short text, sparse data, and noisy data. We validate the practical efficiency of BOPE in two contexts: text analysis and recommender systems. Both contexts show the superior of BOPE over the baselines.

Polymer coating has drawn increasing attention as a leading strategy to overcome the drawbacks of superparamagnetic iron oxide nanoparticles (SPIONs) in targeted delivery of anticancer drugs. In this study, SPIONs were modified with heparin-Poloxamer (HP) shell to form a SPION@HP core-shell system for anticancer drug delivery. The obtained formulation was characterized by techniques including transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR), vibration sample magnetometer (VSM), proton nuclear magnetic resonance (1H-NMR), and powder X-ray diffraction (XRD). Results showed the successful attachment of HP shell on the surface of SPION core and the inability to cause considerable effects to the crystal structure and unique magnetic nature of SPION. The core-shell system maintains the morphological features of SPIONs and the desired size range. Notably, Doxorubicin (DOX), an anticancer drug, was effectively entrapped into the polymeric shell of SPION@HP, showing a loading efficiency of 66.9 ± 2.7% and controlled release up to 120 h without any initial burst effect. Additionally, MTT assay revealed that DOX-loaded SPION@HP exerted great anticancer effect against HeLa cells and could be safely used. These results pave the way for the application of SPION@HP as an effective targeted delivery system for cancer treatment.

Purpose: In the Industrial Revolution 4.0 (IR 4.0), higher education (HE) continues to retain a significant role in providing the growth in quality of manpower level. The English language is an international language that is used in multi-aspects including medicine, economics, media, science, and higher education. English learning quality enhancement is continuously requiring at higher education institutions. This study aims to explore the English language learning quality of university students in Vietnam with the moderating role of the competition factor. Methodology: The study employs qualitative and quantitative research methods. The questionnaire has been developed as a key tool for collecting data based on recommendations of experts, viewpoints of students from the qualitative research results, and from the theoretical outcomes of meta-analysis in previous studies. The sample was randomly selected with 304 responses. Findings: The findings confirm that four factors affecting the quality of English learning are (1) Student's subjective factors, (2) Learning Environment, (3) Quality of Teaching Facilitator, and (4) Teaching Curriculum. In addition, the study showed the positive impact of the "Competition factor" on the relationship between the learning environment, the quality of teaching facilitators, and English language learning quality. Implications for Research and Practice. In addition, suggestions, and implications for managers of educational institutions are included to improve the effectiveness of English education for students.