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21.
In this work, a low-cost, high-yield hydrothermal treatment was used to produce nanozeolite (Zeo), nanoserpentine (Serp), and Zeo/Serp nanocomposites with weight ratios of 1:1 and 2:1. At 250 °C for six hours, the hydrothermal treatment was conducted. Various methods are used to explore the morphologies, structures, compositions, and optical characteristics of the generated nanostructures. The morphological study revealed structures made of nanofibers, nanorods, and hybrid nanofibril/nanorods. The structural study showed clinoptilolite monoclinic zeolite and antigorite monoclinic serpentine with traces of talcum mineral and carbonates. As a novel photoelectrochemical catalyst, the performance of the Zeo/Serp (2:1) composite was evaluated for solar hydrogen generation from water splitting relative to its constituents. At −1 V, the Zeo/Serp (2:1) composite produced a maximum current density of 8.44 mA/g versus 7.01, 6.74, and 6.6 mA/g for hydrothermally treated Zeo/Serp (1:1), Zeo, and Serp, respectively. The Zeo/Serp (2:1) photocatalysts had a solar-to-hydrogen conversion efficiency (STH) of 6.5% and an estimated hydrogen output rate of 14.43 mmole/h.g. Consequently, the current research paved the way for low-cost photoelectrochemical catalytic material for efficient solar hydrogen production by water splitting.  相似文献   
22.
Rabies virus (RABV) has a broad host range and infects multiple cell types throughout the infection cycle. Next-generation sequencing (NGS) and minor variant analysis are powerful tools for studying virus populations within specific hosts and tissues, leading to novel insights into the mechanisms of host-switching and key factors for infecting specific cell types. In this study we investigated RABV populations and minor variants in both original (non-passaged) samples and in vitro-passaged isolates of various CNS regions (hippocampus, medulla oblongata and spinal cord) of a fatal human rabies case, and of multiple CNS and non-CNS tissues of experimentally infected mice. No differences in virus populations were detected between the human CNS regions, and only one non-synonymous single nucleotide polymorphism (SNP) was detected in the fifth in vitro passage of virus isolated from the spinal cord. However, the appearance of this SNP shows the importance of sequencing newly passaged virus stocks before further use. Similarly, we did not detect apparent differences in virus populations isolated from different CNS and non-CNS tissues of experimentally infected mice. Sequencing of viruses obtained from pharyngeal swab and salivary gland proved difficult, and we propose methods for improving sampling.  相似文献   
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24.
Alopecia areata is a skin disorder characterized by scarless, localized hair loss that is usually managed by topical treatments that might further worsen the condition. Therefore, the current study aimed to develop nano-cubosomes loaded with finasteride (FI) and oregano oil (Or) to improve drug solubility and permeation through skin and then incorporate it into an aloe ferox gel base. An l-optimal coordinate exchange design was adopted to optimize nano-cubosomes. Phytantriol and Alkyl Acrylate were employed as the lipid material, and surfactant respectively for cubosomes manufacture. The produced formulations were assessed for their particle size, entrapment efficiency (EE%), FI steady-state flux (Jss) and minimum inhibitory concentration (MIC) against Pro-pionibacterium acnes. Optimal FI-Or-NCu had a particle size of 135 nm, EE% equals 70%, Jss of 1.85 μg/cm2.h, and MIC of 0.44 μg/ml. The optimum formulation loaded gel gained the highest drug release percent and ex vivo skin permeation compared to FI aqueous suspension, and pure FI loaded gel. Aloe ferox and oregano oil in the optimized gel formulation had a synergistic activity on the FI permeation across the skin and against the growth of p. acne bacteria which could favor their use in treating alopecia. Thus, this investigation affirms the ability of FI-Or-NCu loaded aloe ferox gel could be an effective strategy that would enhance FI release and permeation through skin and maximize its favorable effects in treating alopecia.  相似文献   
25.
The oxygen uptake by slices of albino rat brain (cerebral) hemispheres, cardiac, skeletal and plain (intestine) muscle tissues were studied in Warburg flasks in the presence of 3 mg doses of Naja haje, N. nigricollis, Walterinnesia aegyptia, Cerastes cerastes, and C. vipera venoms added in vitro. Statistically significant inhibition of oxygen uptake by brain tissue resulted in the case of all five venoms. No statistically significant inhibition of oxygen uptake was observed in skeletal muscle tissue slices in the presence of the venoms. Statistically significant inhibition of oxygen uptake was observed in cardiac and in plain muscle tissue slices in the presence of N. nigricollis and W. aegyptia venoms only but not in the presence of the other three venoms.  相似文献   
26.
Bio-based silica, lignocellulose, and activated carbon were simply produced via the recycling of Hassawi rice biomass waste of Al-Ahsa governorate in the eastern Saudi Arabia region using a fast chemical treatment procedure. Rice husk and rice straw wastes were collected, ground, and chemically treated with sodium hydroxide to extract silica/silicate from the dried plant tissues. The liquid extract is then treated with acid solutions in order to precipitate silica/silicate at neutral medium. Lowering the pH of the supernatant to 2 resulted in the precipitation of lignocellulose. Thermal treatment of the biomass residue under N2 gas stream resulted in activated carbon production. Separated products were dried/treated and characterized using several physical examination techniques, such as FT-IR, SEM/EDX, XRD, and Raman spectroscopy in order to study their structure and morphology. Silica and lignocelluloses products were then preliminarily used in the treatment of wastewaters and water-desalination processes.  相似文献   
27.
Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality.  相似文献   
28.
ObjectivesTo evaluate the dental arch changes produced by the miniscrew-supported palatal crib (MSPC) and the conventional fixed palatal crib (CFPC) after the treatment of patients with anterior open bite (AOB) attributed to the tongue-thrusting habit in the mixed dentition stage.Materials and MethodsA total of 26 children aged 8 to 11 years with an AOB were randomly distributed into two equal groups; the MSPC group was treated using a palatal crib supported by two miniscrews inserted paramedially, whereas the CFPC group was treated using a conventional fixed palatal crib soldered to bands. Digital models were obtained pretreatment and after a follow-up duration of 9 months.ResultsThe MSPC group included 12 participants (9 girls and 3 boys; mean age, 9.4 ± 0.75 years), and the CFPC group included 12 participants (10 girls and 2 boys; mean age, 9.0 ± 0.73 years). The amount of AOB closure was similar in both groups: 3.97 ± 1.44 mm in the MSPC group and 3.97 ± 0.89 mm in the CFPC group. There was significant mesial movement of the maxillary first molar in the CFPC (−1.42 ± 0.99 mm) compared with the MSPC group (−0.53 ± 0.32 mm).ConclusionsBoth appliances resulted in similar improvement in the amount of AOB closure. There was significantly more mesial movement of the maxillary first molars in the CFPC group compared with the MSPC group.  相似文献   
29.
The present work aims to study the photocatalytic properties of nanohybrids composed of silicon nanowires (SiNWs) decorated with PbS nanoparticles (NPs). The elaborated material was intended to be utilized in wastewater treatment. The SiNWs were elaborated from the Metal Assisted Chemical Etching route (MACE), while the PbS NPs were deposited at room temperature onto SiNWs using the pulsed laser deposition (PLD) technique. The influence of decorating SiNWs (having different lengths) with PbS-NPs on their structural, morphological, optoelectronic, and photocatalytic properties was scrutinized. PbS/SiNWs nanohybrids exhibited enhanced photocatalytic degradation towards Black Amido (BA) dye for 20 µm SiNWs length and 0.2% of BA volume concentration. These optimized conditions may insinuate that this nanocomposite-like structure is a promising efficient photocatalytic systems contender, cost-effective, and recyclable for organic compound purification from wastewaters.  相似文献   
30.
ContextTraditionally, Oleaceae plants are used to treat many diseases, such as rheumatism, hypercholesterolaemia, or ulcers.ObjectivesTo investigate the cytotoxic potential of Jasminum humile L., Jasminum grandiflorum L., and Olea europaea L. (Oleaceae) extracts against selected human cancer cells lines, followed by a phytochemical investigation of the most potent one.Materials and methodsThe 95% ethanol extracts of aerial parts of three oleaceous plants were examined for their cytotoxicity against HepG-2, MCF-7, and THP-1 cell lines using MTT assay and doxorubicin (positive control). J. humile was bio-selected and submitted to bio-guided fractionation. Chromatographic workup of ethyl acetate and n-butanol fractions afforded two new compounds; 1-methoxyjasmigenin (1) and 1-methyl-9-aldojasmigenin (2), along with five known ones (3–7). Structures were unambiguously elucidated using 1D/2D NMR and ESI-HRMS. Isolated compounds were assessed for their anti-proliferative potential, and both selectivity index and statistical significance were determined. Molecular docking was conducted against the Mcl-1 receptor using (AZD5991) as a standard.ResultsJasmoside (5) was the most potent anticancer compound showing IC50 values of 66.47, 41.32, and 27.59 µg/mL against HepG-2, MCF-7, and THP-1 cell lines, respectively. Moreover, isojasminin (4) exhibited IC50 values of 33.49, 43.12, and 51.07 µg/mL against the same cell lines, respectively. Interestingly, 5 exhibited the highest selectivity index towards MCF-7 and THP-1, even greater than doxorubicin. Molecular docking results were in full agreement with the MTT assay and the proposed SAR.ConclusionIn this study, two new compounds were purified. The biological activity highlighted jasmoside (5) as a lead anticancer drug for further future investigation.  相似文献   
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