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1.
Sci Rep ; 14(1): 13536, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866821

RESUMO

Reduced Reinforced Concrete Material Waste (RRCMW) in building projects is regarded as a critical issue that must be managed. The main purpose of the research is to illustrate the importance of BIM in construction. Also, it is found that the main objectives of this paper are to study the improvement of practicing BIM in Egypt and, practicing of BIM in construction industry in Egypt is also measured. Two questionnaires survey are conducted. The first questionnaire is to measure the improvement of using BIM during the last 7 years and it is discovered that there is a massive improvement in using BIM in this period. The second questionnaire is to determine the adopting value of BIM in Egyptian projects in order to meet the study objective. So, based on the questionnaire analysis, it is discovered that about 94% of consultants actually practicing BIM in 3D while about 72% of contractors agree with practicing BIM in 3D. Also it is found that about 86% and 78% of consultants actually practicing BIM in 4D and 5D while only about 43% and 40% of contractors agree with practicing BIM 4D and 5D model respectively. Only about 61% and 58% considered that BIM is important in 6D and 7D respectively because it isn't widely used in Egypt and engineers use BIM up to 5D. As a result, the findings reveal that the number of consultant's site engineer's respondents are more than contractors because the usage of BIM is effective in the field of design and consultancy more than using in site and while BIM isn't extensively utilized in Egypt, engineers should be familiar with it because it will be a useful tool in the future. So, the main purpose of this study is to illustrate practicing of BIM in the Egyptian construction projects and study the improvement of using BIM during the last 7 years in Egypt because BIM is considered as an important technology used to reduce waste in construction projects from design stage to construction and operation stage but still not used in Egypt in a wide range till now, so it is very crucial to study this issue. Also, another main objective of this study is to compare the development done in using BIM during the last 8 years to make sure that using BIM in Egypt is going on and developed.

2.
Eur J Pharm Sci ; 192: 106652, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008226

RESUMO

Catechin is a naturally occurring flavonoid of the flavan-3-ol subclass with numerous biological functions; however, these benefits are diminished due to several factors, including low water solubility and degradation in the stomach's harsh environment. So, this study aimed to develop an intelligent catechin colon-targeting delivery system with a high loading capacity. This was done by coating surface-decorated mesoporous silica nanoparticles with a pH-responsive enteric polymer called Eudragit®-S100. The pristine wormlike mesoporous silica nanoparticles (< 100 nm) with high surface area and large total pore volume were effectively synthesized and modified with the NH2 group using the post-grafting strategy. Various parameters, including solvent polarity, catechin-carrier mass ratio, and adsorption time, were studied to improve the loading of catechin into the aminated silica nanoparticles. Next, the negatively charged Eudragit®-S100 was electrostatically coated onto the positively charged aminated nanocarriers to shield the loaded catechin from the acidic environment of the stomach (pH 1.9) and to facilitate site-specific delivery in the acidic environment of the colon (pH 7.4). The prepared nanomaterials were evaluated using several methods, including The Brauner-Emmett-Teller, surface area analyzer, zeta sizer, Field Emission Scanning Electron Microscope, Powder X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, Energy-Dispersive X-ray Spectroscopy, and Differential Scanning Calorimetry. In vitro dissolution studies revealed that Eudragit®-S100-coated aminated nanomaterials prevented the burst release of the loaded catechin in the acidic environment, with approximately 90% of the catechin only being released at colonic pH (pH > 7) with a supercase II transport mechanism. As a result, silica nanoparticles coated with Eudragit®-S100 would provide an innovative and promising approach in targeted nanomedicine for the oral delivery of catechin and related medicines for treating diseases related to the colon, such as colorectal cancer and irritable bowel syndrome.


Assuntos
Catequina , Nanopartículas , Preparações de Ação Retardada/metabolismo , Dióxido de Silício/química , Portadores de Fármacos/química , Nanopartículas/química , Colo/metabolismo , Concentração de Íons de Hidrogênio , Sistemas de Liberação de Medicamentos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Artigo em Inglês | MEDLINE | ID: mdl-38109475

RESUMO

Novel anion-exchange electrospun fiber membranes of polycaprolactone doped with the cationic, cross-linked colesevelam polymer are reported. The weight fraction of cross-linked cationic colesevelam polymer, as the active phase within the PCL matrix, can readily be controlled in the synthesis of the mixed-matrix fibers (Cole@PCL), enabling optimization of the ion-exchange properties of the resulted membranes. This approach enabled adaptation of anion-exchange resins to a permeable, flexible membrane form, which is a significant advancement toward futuristic water treatment applications, demonstrated herein for the removal of trace contaminants, including nitrates and phosphates, as well as anionic dyes. The Cole@PCL membranes demonstrated the dependence of contaminant uptake on the weight percentage of colesevelam in the mixed-matrix membrane. An optimal 10 wt % of colesevelam was identified, demonstrating a staggering ion removal capacity of 155.8 mg/g for nitrate, 177.6 mg/g for phosphate, and 70 mg/g for Methyl Orange.

4.
Nanomaterials (Basel) ; 13(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36985985

RESUMO

The increase of global environmental restrictions concerning solid and liquid industrial waste, in addition to the problem of climate change, which leads to a shortage of clean water resources, has raised interest in developing alternative and eco-friendly technologies for recycling and reducing the amount of these wastes. This study aims to utilize Sulfuric acid solid residue (SASR), which is produced as a useless waste in the multi-processing of Egyptian boiler ash. A modified mixture of SASR and kaolin was used as the basic component for synthesizing cost-effective zeolite using the alkaline fusion-hydrothermal method for the removal of heavy metal ions from industrial wastewater. The factors affecting the synthesis of zeolite, including the fusion temperature and SASR: kaolin mixing ratios, were investigated. The synthesized zeolite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), particle size analysis (PSD) and N2 adsorption-desorption. The SASR: kaolin weight ratio of 1:1.5 yields faujasite and sodalite zeolite with 85.21% crystallinity, which then shows the best composition and characteristics of the synthesized zeolite. The factors affecting the adsorption of Zn2+, Pb2+, Cu2+, and Cd2+ ions from wastewater on synthesized zeolite surfaces, including the effect of pH, adsorbent dosage, contact time, initial concentration, and temperature, have been investigated. The obtained results indicate that a pseudo-second-order kinetic model and Langmuir isotherm model describe the adsorption process. The maximum adsorption capacities of Zn2+, Pb2+, Cu2+, and Cd2+ ions onto zeolite at 20 °C were 12.025, 15.96, 12.247, and 16.17 mg·g-1, respectively. The main mechanisms controlling the removal of these metal ions from aqueous solution by synthesized zeolite were proposed to be either surface adsorption, precipitation, or ion exchange. The quality of the wastewater sample obtained from the Egyptian General Petroleum Corporation (Eastern Desert, Egypt) was highly improved using the synthesized zeolite and the content of heavy metal ions was significantly reduced, which enhances the utilization of the treated water in agriculture.

5.
ACS Omega ; 8(6): 5184-5196, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816672

RESUMO

Enzymes play vital roles in diverse industrial sectors and are essential components of many industrial products. Immobilized enzymes possess higher resistance to environmental changes and can be recovered/recycled easily when compared to the free forms. The primary benefit of immobilization is protecting the enzymes from the harsh environmental conditions (e.g., elevated temperatures, extreme pH values, etc.). The immobilized enzymes can be utilized in various large-scale industries, e.g., medical, food, detergent, textile, and pharmaceutical industries, besides being used in water treatment plants. According to the required application, a suitable enzyme immobilization technique and suitable carrier materials are chosen. Enzyme immobilization techniques involve covalent binding, encapsulation, entrapment, adsorption, etc. This review mainly covers enzyme immobilization by various techniques and their usage in different industrial applications starting from 1992 until 2022. It also focuses on the multiscale operation of immobilized enzymes to maximize yields of certain products. Lastly, the severe consequence of the COVID-19 pandemic on global enzyme production is briefly discussed.

6.
Int J Immunopathol Pharmacol ; 37: 3946320231152835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36649477

RESUMO

OBJECTIVES: Since being declared a global pandemic, the SARS-CoV-2 virus had a significant impact on the entire globe. The pandemic has placed a heavy burden on healthcare systems worldwide, and cancer patients are particularly prone. Despite the fact that initial international reports suggest delays in breast cancer (BC) diagnosis and screening programs, the Egyptian context requires additional research on this topic. To examine whether COVID-19 has changed the pattern of disease presentation before and after the pandemic, focusing on the tumor, node, and metastasis (TNM) staging of the disease at the initial presentation. METHODS: This single-center, retrospective study of female BC patients initially diagnosed at Baheya Foundation was conducted during the following time frames: from Jan 2019 to Jan 2020 (Pre COVID-19 cohort) and from Mar 2020 to Mar 2021 (post-COVID-19 cohort). We compared the two cohorts in terms of clinical characteristics, tumor characteristics, and the number of days from presentation to treatment. Our primary endpoint was the difference in the TNM stage of BC at the initial presentation. RESULTS: This analysis included 710 BC patients, 350 from the pre-COVID cohort and 360 from the post-COVID group. We detected a 27.9% increase in late-stage BC (stages III-IV) in the post-pandemic cohort compared to the pre-pandemic (60.1% vs. 47%, p < 0.001). The time from diagnosis to commencement of treatment was significantly longer (28.34 ± 18.845 vs 36.04 ± 23.641 days, p < 0.001) in the post-COVID cohort (mean difference = 7.702, 95% CI 4.54-10.85, p < 0.001). A higher percentage of patients in the post-pandemic cohort received systemic neoadjuvant therapy (p-value for Exact's test for all treatment options = 0.001). CONCLUSIONS: The number of patients requiring systemic neoadjuvant chemotherapy increased dramatically in the post-pandemic group with advanced stages of BC at presentation. This study highlights the need for proper management of cancer patients during any future pandemic.


Assuntos
Neoplasias da Mama , COVID-19 , Humanos , Feminino , Neoplasias da Mama/terapia , Neoplasias da Mama/diagnóstico , Estudos Retrospectivos , SARS-CoV-2 , Estadiamento de Neoplasias , Egito/epidemiologia
7.
Front Plant Sci ; 13: 1019014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457524

RESUMO

Microorganism-related technologies are alternative and traditional methods of metal recovery or removal. We identified and described heavy metal-resistant bacteria isolated from polluted industrial soils collected from various sites at a depth of 0-200 mm. A total of 135 isolates were screened from polluted industrial soil. The three most abundant isolate strains resistant to heavy metals were selected: Paenibacillus jamilae DSM 13815T DSM (LA22), Bacillus subtilis ssp. spizizenii DSM 15029T DSM (MA3), and Pseudomonas aeruginosa A07_08_Pudu FLR (SN36). A test was conducted to evaluate the effect of (1) isolated heavy metal-resistant bacteria (soil application), (2) a foliar spray with silicon dioxide nanoparticles (Si-NPs), and (3) moringa leaf extract (MLE) on the production, antioxidant defense, and physio-biochemical characteristics of spinach grown on heavy metal-contaminated soil. Bacteria and MLE or Si-NPs have been applied in single or combined treatments. It was revealed that single or combined additions significantly increased plant height, shoot dry and fresh weight, leaf area, number of leaves in the plant, photosynthetic pigments content, total soluble sugars, free proline, membrane stability index, ascorbic acid, relative water content, α-tocopherol, glycine betaine, glutathione, and antioxidant enzyme activities (i.e., peroxidase, glutathione reductase, catalase, superoxide dismutase, and ascorbate peroxidase) compared with the control treatment. However, applying bacteria or foliar spray with MLE or Si-NPs significantly decreased the content of contaminants in plant leaves (e.g., Fe, Mn, Zn, Pb, Cd, Ni, and Cu), malondialdehyde, electrolyte leakage, superoxide radical ( O 2 · - ) , and hydrogen peroxide (H2O2). Integrative additions had a more significant effect than single applications. It was suggested in our study that the integrative addition of B. subtilis and MLE as a soil application and as a foliar spray, respectively, is a critical approach to increasing spinach plant performance and reducing its contaminant content under contaminated soil conditions.

8.
Biomater Sci ; 10(5): 1342-1351, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35107101

RESUMO

Adenosine is a small molecule directly involved in maintaining homeostasis under pathological and stressful conditions. Due to its rapid metabolism, delivery vehicles capable of exhibiting extended release of adenosine are of paramount interest. Herein, we demonstrate a superior long-term (9 days) release profile of adenosine from biocompatible MOFs in a physiologically relevant environment. The key to the biocompatibility of MOFs is their stability under biologically relevant conditions. This study additionally highlights the interplay between the chemical stability of prototypal MOFs, assessed under physiological conditions, and their cytotoxicity profiles. Cytotoxicity of the prototypal Zn-based MOF (ZIF-8) and three Zr-based MOFs (UiO-66, UiO-66-NH2, and MOF-801) on six cell types was assessed. The cell types selected were valve interstitial cells (VICs), valve endothelial cells (VECs), adipose tissue-derived stem cells (ADSCs), and cell lines U937, THP1, and HeLa. Zr-based MOFs demonstrated a wide tolerance range in the cell culture cytotoxicity assays, demonstrating cell viability up to a very high dose of ∼1000 µg mL-1, as compared to ZIF-8 which showed notable cytotoxicity in as little as ∼100 µg mL-1 dose. This study demonstrates, for the first time, the utilization of biocompatible MOFs for adenosine delivery as well as establishes a direct link between structural instability in the cell culture medium and the observed cytotoxicity of the studied MOFs.


Assuntos
Estruturas Metalorgânicas , Compostos Organometálicos , Adenosina , Células Endoteliais , Humanos , Estruturas Metalorgânicas/química , Ácidos Ftálicos
9.
Pediatr Emerg Care ; 37(12): e1044-e1050, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31348207

RESUMO

OBJECTIVES: Few studies investigated the correlation between foreign body (FB) ingestion and occurrence of complications. The local literature is limited to case reports and small case series on esophageal FBs. We conducted this study to identify the high-risk factors predisposing to complications among Saudi children ingesting FBs. METHODS: The medical records of 436 children (boys, 59.6%; mean age, 4.4 ± 2.7 years) presenting to the emergency department (ED) between 2007 and 2016 were retrospectively reviewed. Relative risk analysis of clinical variables was performed between 2 groups: The first group constituted children without FB-related complications (n = 389), and the second group included those with major complications (n = 14). Major complication was defined as any event associated with significant morbidity such as esophageal stricture, esophageal perforation, esophageal fistula, and intestinal perforation or fistula formation. RESULTS: Most of the 436 cases presented between ages 2 and 4 years (35.1%). Coin was the most commonly ingested FB (22.9%) followed by button battery (19.5%). Most of the ingested FBs passed spontaneously without intervention (69%). Upper endoscopy was performed in 121 cases (27.7%). By multivariate analysis, the variables that were significantly associated with major complications included the following: very young age group (0-2 years; odds ratio [OR], 11.5), button battery (OR, 4), FB impacted at upper esophagus (OR, 8.7), and longer time duration to visit the ED (OR, 14.7). CONCLUSION: Button battery impaction at upper esophagus in very young children and delayed presentation to the ED were the most significant risk factors of FB-related complications.


Assuntos
Corpos Estranhos , Criança , Pré-Escolar , Esôfago , Feminino , Corpos Estranhos/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Arábia Saudita/epidemiologia , Centros de Atenção Terciária
10.
Eur J Pharm Sci ; 142: 105103, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648050

RESUMO

Porous carriers have been put forward as a promising alternative for stabilizing the amorphous state of loaded drugs, and thus significantly improving the dissolution rate of poorly soluble compounds. The purpose of this study was to enhance the saturation solubility, dissolution rate and drug loading of the poorly water-soluble drug silymarin via incorporation into mesoporous silica nanospheres within a lyophilized tablet to obtain a unique formulation. 32 full factorial design was applied to study the effect of both independent variables, polyvinyl alcohol (PVA) as stabilizer and binder and sucrose as cryoprotectant and disintegrant; and on the dependent variables that included the mean particle size (Y1), disintegration time (Y2), tablet strength (Y3) and % of drug release after 2 min, R2min,Y4. The drug-loaded mesoporous silica nanospheres and the optimized formula was evaluated by different characterization methods: scanning electron microscopy, transmission electron microscopy, differential scanning calorimetry, X-ray diffractometry and Fourier transform infrared spectroscopy; as well as drug content, saturation solubility and moisture content. The evaluation demonstrated that the loaded mesoporous silica nanospheres and the optimized formula are in amorphous state without any chemical interaction with the silica matrix or the stabilizer. Moreover, the drug was stably maintained in nanosize range with narrow particle size distribution. Furthermore, the optimized lyophilized tablets had highly porous structure, low friability (less than 1%), fast disintegration (less than 30 s), high tablet strength, low moisture content (less than 1%), remarkably increased dissolution rate and noticeable improvement in saturation solubility.


Assuntos
Nanosferas/química , Dióxido de Silício/química , Silimarina/química , Solubilidade/efeitos dos fármacos , Comprimidos/química , Água/química , Varredura Diferencial de Calorimetria/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos/efeitos dos fármacos , Liofilização/métodos , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Tamanho da Partícula , Álcool de Polivinil/química , Porosidade/efeitos dos fármacos , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
11.
Inorg Chem ; 58(22): 15078-15087, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31661254

RESUMO

The remarkable water stability of Zr-carboxylate-based metal-organic frameworks (MOFs) stimulated considerable interest toward their utilization in aqueous phase applications. The origin of such stability is probed here through pH titration and pKa modeling. A unique feature of the Zr6(µ3-OH)4(µ3-O)4(RCO2)12 cluster is the Zr-bridging oxo/hydroxyl groups, demonstrating several pKa values that appear to provide for the water stability at a wide range of pH. Accordingly, the tunability of the cage/surface charge of the MOF can feasibly be controlled through careful adjustment of solution pH. Such high stability, and facile control over cage/surface charge, can additionally be augmented through introducing chemical functionalities lining the cages of the MOF, specifically amine groups in the UiO-66-NH2 presented herein. The variable protonation states of the Zr cluster and the pendant amino groups, their H-bond donor/acceptor characteristics, and their electrostatic interactions with guest molecules were effectively utilized in controlled experiments to demonstrate high uptake of model guest molecules (137 mg/g for Cr(VI), 1275 mg/g for methylene blue, and 909 mg/g for methyl orange). Additionally, a practical form of the silica-supported MOF, UiO-66-NH2@SiO2, constructed in under 2 h reaction time, is described, generating a true platform microporous sorbent for practical use in demanding applications.

12.
Int J Pharm ; 563: 217-227, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30946894

RESUMO

Silymarin (SLM) is a hepatoprotective herbal drug characterized by low aqueous solubility and, consequently, low oral bioavailability. The objective of this study was to enhance the physiochemical properties of SLM, through preparation and optimization of lyophilized nanosuspension tablets (LNTs). LNTs were prepared by sonoprecipitation technique followed by a freeze-drying process using both polyvinyl alcohol (PVA) as stabilizer and binder, and mannitol as cryoprotectant and disintegrating agent. 32 full factorial design (FFD) was applied to study the effect of independent variables at different concentrations of both PVA (X1) and mannitol (X2) on the dependent variables that included mean particle size (Y1), disintegration time (Y2), friability % (Y3) and time required to release 90% of the drug (Y4). Several physicochemical evaluations were implemented on the optimized formula; for instance differential scanning calorimetry, X-ray diffractometry, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. These analyses demonstrated that the drug was in an amorphous state, stable in nanosize range and displayed no chemical interaction with the polymer. Moreover, the optimized formula had highly porous structure, rapid disintegration, friability with less than 1% and noticeable improvement in saturation solubility and dissolution rate.


Assuntos
Nanopartículas/química , Silimarina/química , Crioprotetores/química , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Liofilização , Manitol/química , Álcool de Polivinil/química , Suspensões , Comprimidos
13.
ACS Appl Mater Interfaces ; 10(39): 32942-32945, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30234959

RESUMO

A facile and versatile method is reported for the inclusion of gold nanoparticles (AuNPs) within a monolithic metal-organic framework (HKUST-1 MOF). Simple addition of stabilized colloidal AuNPs solution to the reaction mixture at the early stages of the formation of the MOF monolith resulted in quantitative uptake of the AuNPs within the MOF matrix. Several characterization techniques including solution and solid UV-vis spectroscopy, TEM, and XRD indicated the successful immobilization of the AuNPs. Controllable loading of AuNPs was also demonstrated, where gas sorption measurements indicated the maintained microporosity of the AuNPs-containing monoliths. This methodology has wide potential applications in demanding technologies, including sensing and catalysis, where monolithic materials of controllable physicochemical properties can be readily accessible through pore size and guest selectivity of the host MOF matrix controlling access of guest molecules to immobilized AuNPs.

14.
Pharm Dev Technol ; 23(4): 358-369, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29069712

RESUMO

The objective of this study was to enhance physiochemical properties as well as oral bioavailability of the poorly water soluble drug fenofibrate (FB), through preparation of amorphous solid dispersions (ASDs). ASDs were prepared via freeze drying using polyvinylpyrrolidone (PVP) K30 and poloxamer 188 as hydrophilic carriers. Formulations were optimized by 32 full factorial design (FFD) with PVP-K30 level (X1) and poloxamer 188 level (X2) as independent variables and particle size (Y1), zeta potential (Y2), drug content (Y3) and dissolution rate (T90, [Y4]) as dependent variables. Optimized FB nanoparticles were physicochemically evaluated and formulated into lyophilized sublingual tablets. Pharmacokinetic, pharmacodynamics and histological finding of optimized formulation were performed on rabbits. Y1 and Y4 were significantly affected by independent variables while Y2 and Y3 were not affected. Physicochemical characterization showed the drug was in amorphous state, nanometer range and pharmacophore of FB was preserved. Administration of optimized FB tablets to rabbits with fatty liver led to significant reduction (p < 0.001) in serum lipids. Moreover, histological analysis of liver specimens confirmed the improved efficacy in animals with fatty liver. In this study, we confirmed that ASDs of FB had beneficial effects on managing fatty liver and serum lipids level in hyperlipidemic rabbits.


Assuntos
Portadores de Fármacos/química , Fenofibrato/administração & dosagem , Hipolipemiantes/administração & dosagem , Nanopartículas/química , Administração Oral , Animais , Disponibilidade Biológica , Fenofibrato/farmacocinética , Fenofibrato/farmacologia , Liofilização , Hipolipemiantes/farmacocinética , Hipolipemiantes/farmacologia , Lipídeos/sangue , Masculino , Tamanho da Partícula , Coelhos , Solubilidade , Comprimidos
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