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1.
Gels ; 10(1)2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38275851

ABSTRACT

Antibiotics are used for the well-being of human beings and other animals. Detectable levels of antibiotics can be found in pharmaceutical, municipal, and animal effluents. Therefore, the treatment of antibiotic contaminated water is of great concern. In this study, we fabricated a sustainable aminated/TEMPO cellulose nanofiber (Am/TEMPO-CNF) aerogel to remove oxytetracycline (OTC) and chloramphenicol (CAP) from synthetic wastewater. The prepared aerogel was characterized using different analytical techniques such as elemental analysis, FTIR, TGA, SEM-EDS, and N2 adsorption-desorption isotherms. The characterization techniques confirmed the presence and interaction of quaternary amine -[NR3]+ and -COOH groups on Am/TEMPO-CNF with OTC and CAP, which validates the successful modification of Am/TEMPO-CNF. The adsorption process of the pollutants was examined as a function of solution pH, concentrations, reaction time, and temperatures. The maximum adsorption capacity was 153.13 and 150.15 mg/g for OTC and CAP, respectively. The pseudo-second order (PSO-2) was well fitted to both OTC and CAP, confirming the removal is via chemisorption. Hydrogen bonding and electrostatic attraction have been postulated as key factors in facilitating OTC and CAP adsorption according to spectroscopic studies. Energetically, the adsorption was spontaneous and endothermic for both pollutants. In conclusion, the efficient removal rate and excellent reusability of Am/TEMPO-CNF indicate the strong potential of the adsorbent for antibiotics' removal.

2.
ACS Omega ; 8(40): 36856-36867, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37841181

ABSTRACT

Nanocellulose-based aerogels, featuring a three-dimensional porous structure, are considered as a desirable green absorbent because of their exceptional absorption performance as well as the abundance and renewability of the raw material. However, these aerogels often require hydrophobic modification or carbonization, which is often environmentally harmful and energy-intensive. In this study, we introduce a Pickering-emulsion-templating approach to fabricate a cellulose nanofibril (CNF) aerogel with a hierarchical pore structure, allowing for high oil absorption capacity. n-Hexane-CNF oil-in-water Pickering emulsions are prepared as an emulsion template, which is further lyophilized to create a hollow microcapsule-based CNF (HM-CNF) aerogel with a density ranging from 1.3 to 6.1 mg/cm3 and a porosity of ≥99.6%. Scanning electron microscopy and Brunauer-Emmett-Teller analyses reveal the HM-CNF aerogel's hierarchical pore structure, originating from the CNF Pickering emulsion template, and also confirm the aerogel's very high surface area of 216.6 m2/g with an average pore diameter of 8.6 nm. Furthermore, the aerogel exhibits a maximum absorption capacity of 354 g/g and 166 g/g for chloroform and n-hexadecane, respectively, without requiring any surface modification or chemical treatment. These combined findings highlight the potential of the Pickering-emulsion-templated CNF aerogel as an environmentally sustainable and high-performance oil absorbent.

3.
Gels ; 9(2)2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36826324

ABSTRACT

Due to the increasingly widespread water pollutants and the high cost of treatment methods, there is a demand for new, inexpensive, renewable, and biodegradable adsorbent materials for the purification of wastewater contaminants. In this study, a new biocomposite aerogel (Amf-CNF/LS) was prepared using a chemically cross-linking method between the amino-functionalized cellulose nanofibers (Amf-CNF) and lignosulfonates (LS). The physical and chemical properties of the prepared aerogel were investigated using several techniques including elemental analysis, scanning electron microscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and N2 adsorption-desorption analysis. The Amf-CNF/LS aerogel was then applied for the removal of methylene blue (MB), rhodamine B dye (RhB), and the heavy metal cadmium ion (Cd2+) from synthetic wastewater solutions. The adsorption parameters controlling the adsorption process including the pH, contact time, adsorbent dosage, and adsorbate concen-tration were optimized. High adsorption kinetics and isotherms were observed, with the adsorption isotherms of the Amf-CNF/LS aerogel fitting the Langmuir model with maximum adsorption capacities of 170.94, 147.28, and 129.87 mg/g for MB, RhB, and Cd2+, respectively. These results show that Amf-CNF/LS aerogel is a promising green and inexpensive adsorbent for MB, RhB, and Cd2+ removal from wastewater.

4.
J Tradit Complement Med ; 10(6): 521-528, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33134128

ABSTRACT

The current study was conducted to investigate the protective properties of Eucalyptus globulus leaves methanolic extract (EGLME) against diclofenac sodium (DS) induced hepatorenal and testicular toxicity in male rats. A total of 40 rats were equally divided into 4 groups, Control, Diclofenac sodium (DS), EGLME and DS + EGLME groups, respectively. DS and EGLME were administered orally at dose rate 2.5 and 100 mg/kg BW, 4 times/week for 8 weeks, respectively. Administration of DS distorted hepatorenal functions manifested by alteration of serum levels of ALT, AST, total protein and albumin, creatinine and urea with changes of histological architectures. DS caused reproductive toxicity represented by minimized sperm count, individual sperm motility and viability; depleted concentration of reduced glutathione (GSH) in testicular tissue; and decreased testosterone level with alteration in testicular histological features. In contrast, co-treatment of DS intoxicated rats with EGLME protected rats against the adverse effects of DS revealing enhancing properties of EGLME on rats' liver, kidney and testes. In conclusion, we demonstrated that EGLME had a potent protecting property against DS induced hepatic, renal and testicular toxicity in male rats, with special concern to testicular tissue via modulation of GSH as an oxidant marker. TAXONOMY: (classification by EVISE): Diclofenac sodium toxicity (hepatorenal and testicular toxicity), co-treatment with natural herbal extract, blood biochemical assays, tissue anti-oxidants assay, histopathology and reproductive indices analyses.

5.
Sci Total Environ ; 748: 142465, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33113689

ABSTRACT

Porous structure design is considered to be a promising strategy for the development of effective sorbents for CO2 capture. Herein, a series of carbon nanoflakes with large surface area (up to 2380 m2/g) and high micropore volume (up to 0.896 m3/g) were synthesized from a renewable precursor, cork dust waste, to capture CO2 at atmospheric pressure. The nanoflakes exhibited superior CO2 uptake performance at 1 bar with the maximum capacity of 7.82 and 4.27 mmol/g at 0 and 25 °C, respectively, in sharp contrast to previously reported porous carbon materials. The existence of large numbers of narrow micropores with the pore width less than 0.86 nm and 0.70 nm play a critical role in the CO2 uptake at 0 and 25 °C, respectively. Moreover, the CNFs exhibited good recyclability and high selectivity for CO2 uptake from the mixture of CO2 and N2. By taking advantage of the unique hollow honeycomb cell, the three-layered cell wall structure, as well as the unique chemical composition of a cork precursor, such delicate microporous carbon nanoflakes were able to be achieved by simple thermal pretreatment combined with chemical activation. This bioinspired precursor-synthesis route poses a great potential for the facile production of porous carbons for a variety of diverse applications including CO2 capture.


Subject(s)
Carbon Dioxide , Carbon , Biomass , Porosity
6.
Chemosphere ; 260: 127683, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32758774

ABSTRACT

This study represents the first ever work on a novel oxone treated hydrochar as an adsorbent for the efficient removal of different contaminants from aqueous solutions. Pine wood hydrochar (HC) was prepared by hydrothermal treatment at 300 °C and oxidized with oxone to produce oxidized pine wood hydrochar (OHC). Different analytical tools such as elemental analysis, FTIR, TGA, FE-SEM, and BET were used for the characterization of the OHC. Conductometric titration of OHC showed a substantial increase from 22 µmol/g to 600 µmol/g in the hydrochar carboxylic content. The OHC sorption performance was assessed by using Pb(II) ions and methylene blue (MB) dye as two models of contaminants. Sorption benchmarks were performed by varying the contaminant initial concentration, time, and temperatures. Sorption kinetic data was fitted well to the pseudo-second order kinetic model with high correlation coefficients (R2 > 0.99) and isothermal data was fitted to the Langmuir model. The highest adsorption capacities for MB and Pb(II) were 86.7 mg/g and 46.7 mg/g, respectively. This study proves that oxone treatment could be a potential sustainable oxidation method to tune the hydrochar surface to increase selectivity towards heavy metal ions and dye sorption.


Subject(s)
Lead/chemistry , Methylene Blue/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Metals, Heavy , Methylene Blue/analysis , Solutions , Sulfuric Acids , Temperature , Water , Water Pollutants, Chemical/analysis
7.
J Viral Hepat ; 27(11): 1190-1201, 2020 11.
Article in English | MEDLINE | ID: mdl-32564500

ABSTRACT

The aim of this study was to assess the efficacy and safety of two protocols for retreatment of a cohort of Egyptian patients with chronic hepatitis C (CHC) who relapsed after NS5A inhibitor-based therapy. We conducted a prospective cohort study to assess the safety and efficacy of 12 weeks' retreatment with either combination of sofosbuvir/daclatasvir/simeprevir plus ribavirin (SOF/DCV/SMV/RBV, n = 45) or sofosbuvir/ombitasvir/paritaprevir/ritonavir plus ribavirin (SOF/OBV/PTV/r/RBV, n = 163) in patients who had previously failed NS5A inhibitors-based regimens. The primary end point was SVR 12 weeks after the end of treatment (SVR12). Safety follow-up data were recorded for 60 weeks after the end of treatment. Two hundred-eight patients were included in the study. Of them, 53.4% of patients were females and 40.4% had liver cirrhosis. The most common prior drug combinations were sofosbuvir/daclatasvir (n = 94) and sofosbuvir/daclatasvir plus ribavirin (n = 109). The overall SVR12 rates were 98.1%. In SOF/DCV/SMV/RBV group, 95.6% achieved SVR12, while in SOF/OBV/PTV/r/RBV group, the SVR12 rates were 98.8%. SVR12 was higher in cirrhotic patients (84/84) than noncirrhotic (120/124), P value = .0149. Regarding the safety outcomes, anaemia and fatigue were significantly higher in SOF/OBV/PTV/r/RBV group. Hepatocellular carcinoma (HCC) was reported in eight (3.8%) patients (four in each group). Of them, death was confirmed in four patients. Retreatment of Egyptian CHC relapsed patients with either sofosbuvir/daclatasvir/simeprevir plus ribavirin or sofosbuvir/ombitasvir/paritaprevir/ritonavir plus ribavirin is highly effective and well-tolerated for both noncirrhotic and compensated cirrhotic patients. Incidental de novo HCC and hepatic decompensation are comparable in the two groups.


Subject(s)
Carcinoma, Hepatocellular , Hepatitis C, Chronic , Liver Neoplasms , Antiviral Agents/therapeutic use , Carcinoma, Hepatocellular/drug therapy , Drug Therapy, Combination , Egypt , Female , Genotype , Hepacivirus , Hepatitis C, Chronic/drug therapy , Humans , Liver Neoplasms/drug therapy , Prospective Studies , Retreatment , Ribavirin/therapeutic use , Sofosbuvir/therapeutic use , Treatment Outcome
8.
J Endod ; 46(2): 184-191, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31889585

ABSTRACT

INTRODUCTION: The aim of this study was to examine the root canal system morphology of mandibular incisors by means of micro-computed tomographic imaging. METHODS: The root canal configuration, physiological foramina, frequency of accessory and connecting canals, and the size and shape of the physiological foramina of 125 mandibular incisors were investigated by means of micro-CT and 3-dimensional imaging software. Root canal configuration of the coronal, middle, and apical thirds and the physiological foramina number are described by a 4-digit system code. RESULTS: The most frequent root canal configurations were 1-1-1/1 (56%), 1-2-1/1 (17.6%), and 1-1-1/2 (10.4%); 9 additional different root canal configurations were observed. Single-rooted incisors showed in 80% 1, in 16% 2, and in 4% 3 physiological foramina, respectively. Accessory canals were found in only 13.6% of the investigated teeth. Connecting canals were observed in 36% of the sample, most often in root canal configurations 1-2-1/1 (12.8%) and 2-2-1/1 (7.2%). The morphologic dimensions of a total of 146 physiological foramina were measured. Their mean wide and narrow diameters were 0.24 mm (standard deviation = 0.1 mm) and 0.23 mm (standard deviation = 0.08 mm) when only 1 physiological foramen was present. The physiological foramen shapes observed were oval (56%), round (28.8%), and irregular (15.2%). CONCLUSIONS: The study provides detailed information about the root canal morphology of anterior teeth in a German population. Within the limitations of the study, the authors recommend according to results obtained in this investigation a final physiological foramen preparation size of ISO 30-35; yet, such a decision should be carefully considered on an individual basis.


Subject(s)
Dental Pulp Cavity , Incisor , Root Canal Therapy , Humans , Mandible , Tooth Root , X-Ray Microtomography
9.
ACS Appl Mater Interfaces ; 11(50): 46714-46725, 2019 Dec 18.
Article in English | MEDLINE | ID: mdl-31741369

ABSTRACT

A simple and novel method, self-assembly of nanocellulose and nanochitin, was developed to produce high-efficiency and versatile biohybrid hydrogel (BHH) and aerogel (BHA) for water purification. The self-assembly process was driven by the electrostatic force between one-dimensional (1D) negatively charged TEMPO-oxidized cellulose nanofiber (TOCNF) and positively charged partly deacetylated chitin nanofiber (PDChNF). The self-assembly process was performed at room temperature and without adding any cross-linking agents throughout the process. This results in the three-dimensional (3D) BHH that physically cross-linked via both electrostatic interactions and hydrogen bonding between TOCNF and PDChNF. The obtained BHA from lyophilized BHH exhibited a highly porous interconnected structure with a specific surface area of 54 m2·g-1, which assures the availability of its internal active site for the adsorption of toxic metalloid ions and organic pollutants. Consequently, the BHA displayed super-high adsorption capacities of 217 mg·g-1 for As(III) under the neutral pH conditions and 531 mg·g-1 for methylene blue (MB) under an alkaline aqueous condition with rapid adsorption kinetics, in sharp contrast to conventional biobased adsorbents. Moreover, the BHA is reusable, which still exhibited a high MB adsorption capacity of 505 mg·g-1 even after five successive adsorption-desorption cycles. This versatile BHA produced via a facile preparation strategy is proven to be a promising renewable adsorbent for water purification, offering simple and green alternatives to the conventional adsorbent from synthetic polymers.

10.
The Egyptian Journal of Hospital Medicine ; 76(7): 4577-4587, 2019. tab
Article in English | AIM (Africa) | ID: biblio-1272778

ABSTRACT

Background: spondyloarthropathies (SpA) are a group of chronic inflammatory rheumatic conditions that share multiple clinical features including axial and/or peripheral arthritis, enthesitis, absence of serum rheumatoid factor and presence of common extra articular manifestations. Objective: the aim of this work is to study bone mineral density and trabecular bone score at patients with non-radiographic axial spondyloarthropathy. Patients and Methods: this study is a cross sectional study in which 200 patients having chronic back pain selected from those attending the outpatient clinic and inpatient of Al-Azhar University Hospitals, Damietta and were divided into two groups: 1- (Group A, study group): (160) patients had inflammatory low back pain fulfilling Calin criteria for inflammatory low back pain. 2- (Group B, control group): (40) patients had mechanical low back pain not fulfilling criteria of inflammatory back pain. Results: regarding results of clinical examination, there was significant increase of arthritis, dactylitis, enthesitis and psoriasis in Group A when compared to Group B (43.3%, 16.7%, 30.0%, 20.0% vs 3.3%, 0.0%, 3.3% and 3.3% respectively). In addition, there was significant increase of arthritis plus dactylitis and arthritis plus enthesitis in Group A when compared to Group B (16.7%, 30.0% vs 3.3% and 0.0% respectively). Conclusion: results of the present study proved that, both bone mineral density and trabecular bone scores showed early changes in patients with non-radiographic axial spondylo-arthropathy. In addition, both correlated with each other and with results of axial magnetic resonance imaging. Thus, they are advocated in diagnosis of nr. SPA


Subject(s)
Bone Density , Bone and Bones , Spondylarthropathies , Trabecular Meshwork
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