Background
Alzheimer’s disease (AD) is the most common cause of dementia among the elderly and is characterized by loss of memory and other cognitive functions. An increase in AChE (a key enzyme in ...the cholinergic nervous system) levels around
β
-amyloid plaques and neurofibrillary tangles is a common feature of AD neuropathology. Amnesic effects of scopolamine (acetylcholine receptor antagonist) can be investigated in various behavioral tests such as Morris water maze, object recognition, Y-maze, and passive avoidance. In the scope of this paper, we report the anti-AChE, anti-BChE properties of the isolated compound and the in vivo effects of the methanolic extract of
Xylia xylocarpa
(MEXX) on scopolamine-induced memory deficit.
Results
In further phytochemistry study, a new hopan-type triterpenoid, (3
β
)-hopan-3-ol-28,22-olide (
1
), together with twenty known compounds were isolated (
2
–
21
). Compound
1
,
2
,
4
,
5
,
7
–
9
, and
11
–
13
exhibited potent acetylcholinesterase (AChE) inhibitory activity in a concentration-dependent manner with IC
50
values ranging from 54.4 to 94.6 μM. Compound
13
was also shown anti-butyrylcholinesterase (BChE) activity with an IC
50
value of 42.7 μM. The Morris water Y-maze, Y-maze, and object recognition test were also carried out.
Conclusions
It is noteworthy that MEXX is effective when administered orally to mice, experimental results are consistent with the traditional use of this medicinal plant species.
Phytochemical investigation of the methanol extract of
Vitex limonifolia
leaves led to the isolation of three new labdane-type diterpenoids, vitexlimolides A–C (
1–3
) and eight known compounds, ...5,4′-dihydroxy-3,7-dimethoxyflavone (
4
), vitecetin (
5
), 5,4′-dihydroxy-7,3′-dimethoxyflavone (
6
), verrucosin (
7
), 2
α
, 3
α
-dihydroxy-urs-12-en-28-oic acid (
8
), euscaphlic acid (
9
), 18,19-seco, 2
α
, 3
α
-dihydroxy-19-oxo-urs-11,13(18)-dien-28-oic acid (
10
), and maslinic acid (
11
). Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for antiviral activities against CVB3, HRV1B, and EV71 viruses. As a result, compounds
4
and
6
showed potent antiviral activity against CVB3 infection with IC
50
values of 0.12 ± 0.06 and 1.86 ± 0.18 (µM), respectively.
Graphical abstract
Parkinson’s disease (PD) is an age-related neurodegenerative disorder characterized by progressive deterioration of motor function and loss of dopaminergic neurons in the substantia nigra. Although ...PD is more common in people over 60 years old, people with young-onset PD tend to increase recently. Up to now, there is no cure for PD; therapies mainly focus on reducing symptoms and improving patient quality of life. Thus, the requirement of exploring new medications is needed. There is a strong relationship between oxidative stress and PD. Therefore, antioxidant compounds have been considered as a novel therapy for PD. In this study, we indicated a new potential candidate for PD treatment, rumdul fruit (Sphaerocoryne affinis—a member of the Annonaceae family), due to evaluating its activities on the fly model of Parkinson. Our experimental results showed that rumdul fruit water extract (RFWE) has a strong antioxidant capacity with IC50 value in DPPH assay which was 85.62±1.05 μg/mL. The use of RFWE at concentrations of 3, 6, and 12 mg/mL could strongly ameliorate the locomotor disabilities and dopaminergic neuron degeneration. Although the RFWE at high concentrations like 12 mg/mL and 18 mg/mL could induce some side effects on fly development and viability, our data strongly demonstrated that RFWE effectively rescued PD phenotypes on the fly model. Although component in the plant extract, as well as the molecular mechanism helping to recover the phenotype, has not been elucidated yet, the research contributed strong scientific evidence for further research on applying rumdul as a novel natural source for PD treatment.
This paper demonstrates the preparation of ZnMn
2
O
4
nanoparticles through thermal hydrolysis in different solvents, such as isopropanol, ethylene glycol, glycerol, and water, combined with ...pyrolysis. The obtained samples were characterised by using X-ray diffraction (XRD), infrared spectroscopy (FT‒IR), scanning electron microscopy (SEM), energy-dispersive X-ray mapping, nitrogen adsorption/desorption isotherms, and a vibrating sample magnetometer. The electrocatalytic activity of ZnMn
2
O
4
nanoparticles was investigated toward the oxidation of uric acid (UA) and xanthine (XA). The ZnMn
2
O
4
-nanoparticle-modified electrode not only enhances the oxidation currents of the two purine derivatives but also successfully separates the voltammetric signals of the analytes in their binary mixture and, hence, is employed for their simultaneous determination. The factors affecting the analysis, such as pH, scan rate, linear range, detection limit, reproducibility, and interferents, were also investigated. The results show that the UA and XA limits of detection are as low as 0.55 and 1.28 µM, and the modified electrodes have satisfactory repeatability and reproducibility. The practical application of the modified electrode was demonstrated by simultaneously determining the concentrations of UA and XA in urine samples with exceptional accuracy.
Lentinus arcularius (=Polyporus arcularius) is a medicinal polypore mushroom recorded in Vietnam based on morphological observation. In this study, three L. arcularius isolates were identified using ...molecular and morphological methods. Furthermore, the antimicrobial and antioxidant activities of their intracellular and/or extracellular metabolites were investigated. The ethyl acetate and n-butanol fractions were the most active extracts against Gram-positive and Gram-negative bacteria (Escherichia coli VTCC 12014, Pseudomonas aeruginosa VTCC 12273, and Staphylococcus aureus VTCC 10658) and fungi (Candida albicans VTCC 20568, Saccharomyces cerevisiae VTCC 20146, and Aspergillus niger VTCC 30001). These fractions also showed the highest antioxidant activity by α,α-diphenyl-β-picryl-hydrazyl as a free-radical agent or the highest percentage at 75-100% inhibition. These results suggest that L. arcularius might be a potential medicinal mushroom with antimicrobial and antioxidant effects.
In this paper, ZnFe2O4 nanomaterial synthesized in different solvents by hydrothermal method was used as catalyst for the benzylation of p-xylene. ZnFe2O4 catalyst was characterized by XRD, EDX, SEM ...and nitrogen adsorption/desorption isotherms. The influence of various parameters in the benzylation of p-xylene such as the Fe content of the prepared materials, the ratio molar of p-xylene/benzyl chloride, the catalyst dosage, and the temperature was investigated. The relationship between adsorption kinetics and reaction kinetics of p-xylene benzylation over ZnFe2O4 nanoparticles was discussed. The results indicated that ZnFe2O4 catalyst synthesized in ethylene glycol (ZFO-EG) showed high conversation for the benzylation of p-xylene. The reusability of the ZFO-EG catalyst was also investigated.
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.
Aims
To determine if neurologic symptoms at admission can predict adverse outcomes in patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2).
Methods
Electronic medical records of ...1053 consecutively hospitalized patients with laboratory‐confirmed infection of SARS‐CoV‐2 from one large medical center in the USA were retrospectively analyzed. Univariable and multivariable Cox regression analyses were performed with the calculation of areas under the curve (AUC) and concordance index (C‐index). Patients were stratified into subgroups based on the presence of encephalopathy and its severity using survival statistics. In sensitivity analyses, patients with mild/moderate and severe encephalopathy (defined as coma) were separately considered.
Results
Of 1053 patients (mean age 52.4 years, 48.0% men n = 505), 35.1% (n = 370) had neurologic manifestations at admission, including 10.3% (n = 108) with encephalopathy. Encephalopathy was an independent predictor for death (hazard ratio HR 2.617, 95% confidence interval CI 1.481–4.625) in multivariable Cox regression. The addition of encephalopathy to multivariable models comprising other predictors for adverse outcomes increased AUCs (mortality: 0.84–0.86, ventilation/ intensive care unit ICU: 0.76–0.78) and C‐index (mortality: 0.78 to 0.81, ventilation/ICU: 0.85–0.86). In sensitivity analyses, risk stratification survival curves for mortality and ventilation/ICU based on severe encephalopathy (n = 15) versus mild/moderate encephalopathy (n = 93) versus no encephalopathy (n = 945) at admission were discriminative (p < 0.001).
Conclusions
Encephalopathy at admission predicts later progression to death in SARS‐CoV‐2 infection, which may have important implications for risk stratification in clinical practice.
Patients with severe acute respiratory syndrome coronavirus 2 infection have a high prevalence of neurologic manifestations, including headache, encephalopathy, dizziness, taste, and smell impairment. Patients with encephalopathy at admission predict later progression to death and mechanical ventilation/ICU admission in SARS‐CoV‐2 infection, which may have important implications for risk stratification in clinical practice.
The purpose of this paper is to ascertain the key factors affecting tax compliance among Vietnamese firms in Vietnam. We employ both qualitative and quantitative research methods. Qualitative ...research has been carried out through focus group discussions with ten chief accountants and tax officers. Quantitative research has been conducted through interviews with 200 firms (chief accountants or financial directors) in Vietnam. Analysis of the model includes the following stages: (i) Cronbach's test for reliability of the scale, (ii) exploratory factor analysis (EFA), (iii) confirmatory factor analysis (CFA), and (iv) structural equation model (SEM). The results of the research show that voluntary tax compliance is directly affected by the three factors of audit probability, corporate reputation and business ownership. The probability of audit and severity of sanctions have the strongest impact on tax compliance. Therefore, the tax authorities need to strengthen the inspection of tax declarations, tax payments and tax refunds of firms. The paper confirms that enforced tax compliance is directly affected by the three factors of audit probability, sanction severity and social norms. Voluntary compliance and compulsory compliance have an effect on tax compliance, though voluntary compliance has a more powerful impact.
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