Aluminum-coated polypropylene films are commonly used in food packaging because aluminum is a great gas barrier. However, recycling these films is not economically feasible. In addition, their ...end-of-life incineration generates harmful alumina-based particulate matter. In this study, coating layers with excellent gas-barrier properties are assembled on polypropylene films through layer-by-layer (LbL) deposition of biorenewable nanocellulose and nanochitin. The coating layers significantly reduce the transmission of oxygen and water vapors, two unfavorable gases for food packaging, through polypropylene films. The oxygen transmission rate of a 60 μm-thick, 20 LbL-coated polypropylene film decreases by approximately a hundredfold, from 1118 to 13.10 cc m−2 day−1 owing to the high crystallinity of nanocellulose and nanochitin. Its water vapor transmission rate slightly reduces from 2.43 to 2.13 g m−2 day−1. Furthermore, the coated film is highly transparent, unfavorable to bacterial adhesion and thermally recyclable, thus promising for advanced food packaging applications.
•Nanocellulose and nanochitin are coated layer-by-layer on polypropylene films.•The coating layers are a high oxygen barrier and highly transparent.•The coated film shows reduced bacterial adhesion and good thermal recyclability.•The coated polypropylene film can function as an advanced food packaging material.
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Chitin is a renewable and sustainable biomass material that can be converted into various one-dimensional crystalline nanomaterials different in 1) length, 2) diameter, 3) charge ...density, 4) type of charge, and 5) crystallinity via diverse top-down synthetic methods. These nanomaterials have great potential as sustainable reinforcing and biologically functional materials. The proper design of chitin nanomaterials maximizes their performances in specific applications. Extensive efforts are devoted to understanding each type of chitin nanomaterial produced from different chitin sources; however, few studies have compared different chitin nanomaterials. Herein, we synthesize five different types of chitin nanomaterials from identical sources and compare their physical and chemical properties, including suitability for assorted purposes. Factors 1)-5) are discussed regarding their dominance in determining functionality depending on the specific goals of a) gas barriers, b) mechanical reinforcements, c) dispersibility in various pH aqueous buffers, d) thermal dimensional stability, and e) antibacterial activity. This study gives insights to design new chitin nanomaterial-based materials.
Well‐known hard‐template methods for nitrogen (N)‐doped chiral carbon nanomaterials require complicated construction and removal of the template, high‐temperature pyrolysis, harsh chemical ...treatments, and additional N‐doping processes. If naturally occurring chiral nematic chitin nanostructures (C8H13NO5)n in exoskeletons were wholly transformed into an N‐doped carbon, this would be an efficient and sustainable method to obtain a useful chiral nanomaterial. Here, a simple, sacrificial‐template‐free, and environmentally mild method was developed to produce an N‐doped chiral nematic carbon‐sheath nanofibril hydrogel with a surface area >300 m2 g−1 and enantioselective properties from renewable chitin biomass. Calcium‐saturated methanol physically exfoliated bulk chitin and produced a chiral nematic nanofibril hydrogel. Hydrothermal treatment of the chiral chitin hydrogel at 190 °C produced an N‐doped chiral carbon‐sheath nanofibril hydrogel without N‐doping. This material preferentially adsorbed d‐lactic acid over l‐lactic acid and produced 16.3 % enantiomeric excess of l‐lactic acid from a racemic mixture.
Chiral chitin: An N‐doped chiral nematic carbon‐sheath nanofibril hydrogel is prepared from renewable chitin biomass by exfoliation of chitin with calcium‐saturated methanol. The material is used for the chiral resolution of lactic acid and preferentially adsorbs d‐lactic acid over l‐lactic acid, producing 16.3 % enantiomeric excess of l‐lactic acid from a racemic mixture.
The pathogenesis and prognosis of patients with acute myocardial infarction (AMI) may be influenced by both genetic and environmental factors. Findings on the relationship of polymorphisms in various ...genes encoding the renin-angiotensin-aldosterone system with coronary artery lesions and mortality in AMI patients are inconsistent. The aim of this study was to determine whether the AGTR1 A1166C genetic polymorphism affects coronary artery lesions and 1-year mortality in post-AMI patients. Patients with their first AMI admitted to Cho Ray Hospital, Vietnam, from January 2020 to August 2021 were enrolled in this prospective clinical study. All participants underwent invasive coronary angiography and were identified as having the genotypes of AGTR1 A1166C by way of a polymerase chain reaction method. All patients were followed up for all-cause mortality 12 months after AMI. The association of the AGTR1 A1166C polymorphism with coronary artery lesions and 1-year mortality was evaluated using logistic regression and Cox regression analysis, respectively. Five hundred and thirty-one AMI patients were recruited. The mean age was 63.9 ± 11.6 years, and 71.6% of the patients were male. There were no significant differences in the location and number of diseased coronary artery branches between the AA and AC+CC genotypes. The AC and CC genotypes were independently associated with ≥ 90% diameter stenosis of the left anterior descending (LAD) artery (odds ratio = 1.940; 95% confidence interval (CI): 1.059-3.552, p = 0.032). The 1-year all-cause mortality rate difference between patients with the AC and CC genotypes versus those with the AA genotype was not statistically significant (hazard ratio = 1.000, 95% CI: 0.429-2.328, p = 1.000). The AGTR1 A1166C genetic polymorphism is associated with very severe luminal stenosis of the LAD but not with mortality in AMI patients.
ABCG2 is an ABC membrane protein reverse transport pump, which removes toxic substances such as medicines out of cells. As a result, drug bioavailability is an unexpected change and negatively ...influences the ADMET (absorption, distribution, metabolism, excretion, and toxicity), leading to multi-drug resistance (MDR). Currently, in spite of promising studies, screening for ABCG2 inhibitors showed modest results. The aim of this study was to search for small molecules that could inhibit the ABCG2 pump. We first used the WISS MODEL automatic server to build up ABCG2 homology protein from 655 amino acids. Pharmacophore models, which were con-structed based on strong ABCG2 inhibitors (IC50 < 1 μM), consist of two hydrophobic (Hyd) groups, two hydrogen bonding acceptors (Acc2), and an aromatic or conjugated ring (Aro|PiR). Using molecular docking method, 714 substances from the DrugBank and 837 substances from the TCM with potential to inhibit the ABCG2 were obtained. These chemicals maybe favor synthesized or extracted and bioactivity testing.
Originating for the first time in Wuhan, China, the outbreak of SARS-CoV-2 has caused a serious global health issue. An effective treatment for SARS-CoV-2 is still unavailable. Therefore, in this ...study, we have tried to predict a list of potential inhibitors for SARS-CoV-2 main protease (Mpro) using a combination of molecular docking and fast pulling of ligand (FPL) simulations. The approaches were initially validated over a set of eleven available inhibitors. Both Autodock Vina and FPL calculations produced consistent results with the experiments with correlation coefficients of
R
Dock
= 0.72 ± 0.14 and
R
W
= −0.76 ± 0.10, respectively. The combined approaches were then utilized to predict possible inhibitors that were selected from a ZINC15 sub-database for SARS-CoV-2 Mpro. Twenty compounds were suggested to be able to bind well to SARS-CoV-2 Mpro. Among them, five top-leads are
periandrin V
,
penimocycline
,
cis-p-Coumaroylcorosolic acid
,
glycyrrhizin
, and
uralsaponin B
. The obtained results could probably lead to enhance the COVID-19 therapy.
A combination of Autodock Vina and FPL calculations suggested that
periandrin V
,
penimocycline
,
cis-p-Coumaroylcorosolic acid
,
glycyrrhizin
, and
uralsaponin B
are able to bind well to SARS-CoV-2 Mpro.
A genome‐wide association study (GWAS) is a powerful tool in investigating genetic contribution, which is a crucial factor in the development of complex multifactorial diseases, such as type 2 ...diabetes mellitus. Type 2 diabetes mellitus is a major healthcare burden in the Western Pacific region; however, there is limited availability of genetic‐associated data for type 2 diabetes in Southeast Asia, especially among the Kinh Vietnamese population. This lack of information exacerbates global healthcare disparities. In this study, 997 Kinh Vietnamese individuals (503 with type 2 diabetes and 494 controls) were prospectively recruited and their clinical and paraclinical information was recorded. DNA samples were collected and whole genome genotyping was performed. Standard quality control and genetic imputation using the 1000 Genomes database were executed. A polygenic risk score for type 2 diabetes was generated in different models using East Asian, European, and mix ancestry GWAS summary statistics as training datasets. After quality control and genetic imputation, 107 polymorphisms reached suggestive statistical significance for GWAS (≤5 × 10−6) and rs11079784 was one of the potential markers strongly associated with type 2 diabetes in the studied population. The best polygenic risk score model predicting type 2 diabetes mellitus had AUC = 0.70 (95% confidence interval = 0.62–0.77) based on a mix of ancestral GWAS summary statistics. These data show promising results for genetic association with a polygenic risk score estimation in the Kinh Vietnamese population; the results also highlight the essential role of population diversity in a GWAS of type 2 diabetes mellitus.
Genetic factors play an important role in the development of type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS). However, few genetic association studies related to these disorders have ...been performed with Vietnamese subjects. In this study, the potential associations of
single nucleotide polymorphisms (SNPs) with T2DM and MetS in a Kinh Vietnamese population were investigated.
A study with 768 subjects was conducted to examine the associations of four
SNPs (rs266729, rs1501299, rs3774261, and rs822393) primarily with T2DM and secondarily with MetS. The TaqMan SNP genotyping assay was used to determine genotypes from subjects' DNA samples.
After statistical adjustment for age, sex, and body mass index, the
SNP rs266729 was found to be associated with increased risk of T2DM under multiple inheritance models: codominant (OR = 2.30, 95% CI = 1.16-4.58), recessive (OR = 2.17, 95% CI = 1.11-4.26), and log-additive (OR = 1.32, 95% CI = 1.02-1.70). However, rs1501299, rs3774261, and rs822393 were not associated with risk for T2DM. Additionally, rs266729, rs3774261, and rs822393 were statistically associated with MetS, while rs1501299 was not. Haplotype analysis showed a strong linkage disequilibrium between the SNP pairs rs266729/rs822393 and rs1501299/rs3774261, and the haplotype rs266729(G)/rs822393(T) was not statistically associated with MetS.
The results show that rs266729 is a lead candidate SNP associated with increased risk of developing T2DM and MetS in a Kinh Vietnamese population, while rs3774261 is associated with MetS only. Further functional characterization is needed to uncover the mechanism underlying the potential genotype-phenotype associations.
Chitin, a sustainable and functional biological macromolecule, can be converted into chitin nanofibers (ChNFs), and are applicable as a mechanically reinforcing and bioactive filler for polymer ...matrices. Improving the performance of ChNFs typically relies on their nanofibrilization and miscibility with matrices. To transform chitin biomass into organo-dispersible ChNFs, a series of time-/energy-consuming chemical and mechanical treatments are required: 1) deacetylation, 2) disintegration, 3) surface modification to minimize their aggregation through hydrogen bonds, 4) drying, and 5) re-dispersion. This paper presents a one-step method to transform chitin biomass to organo-dispersible acetylated ChNFs via a ball-milling method in the presence of relatively low toxic acetic anhydride without water. This method minimizes water contaminations and energy for dehydrating. The resulting chitin nanofiber material is mixed with poly(l‑lactic acid) (PLLA) to produce all-bio-based nanocomposites. The composite indicated a 66% increase in Young's modulus and a 100% increase in tensile strength compared to the pristine PLLA. Furthermore, it did not exhibit any observable cytotoxic effect, thus potentially applicable as a biomedical material.
•A one-step method transformed chitin biomass to chitin nanofiber.•All-bio-based nanocomposites had poly(l‑lactic acid) and one-step chitin nanofiber.•The composite indicated a 100% increase in tensile strength.•The composite did not exhibit any observable cytotoxic effect.
Alzheimer’s disease (AD) is a neurodegenerative disorder and one of the main causes of dementia. The disease is associated with amyloid beta (Aβ) peptide aggregation forming initial clusters and then ...fibril structure and plaques. Other neurodegenerative diseases such as type 2 diabetes, amyotrophic lateral sclerosis, and Parkinson’s disease follow a similar mechanism. Therefore, inhibition of Aβ aggregation is considered an effective way to prevent AD. Recent experiments have provided evidence that oligomers are more toxic agents than mature fibrils, prompting researchers to investigate various factors that may influence their properties. One of these factors is nanomechanical stability, which plays an important role in the self-assembly of Aβ and possibly other proteins. This stability is also likely to be related to cell toxicity. In this work, we compare the mechanical stability of Aβ-tetramers and fibrillar structures using a structure-based coarse-grained (CG) approach and all-atom molecular dynamics simulation. Our results support the evidence for an increase in mechanical stability during the Aβ fibrillization process, which is consistent with in vitro AFM characterization of Aβ42 oligomers. Namely, using a CG model, we showed that the Young modulus of tetramers is lower than that of fibrils and, as follows from the experiment, is about 1 GPa. Hydrogen bonds are the dominant contribution to the detachment of one chain from the Aβ fibril fragment. They tend to be more organized along the pulling direction, whereas in the Aβ tetramers no preference is observed.
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