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1.
Environ Pollut ; 360: 124687, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39116919

RESUMO

The present study systematically investigated the elimination of benzalkonium chloride (BAC) in the zero valent iron activated persulfate (Fe0/PS) system. The influence of operational parameters, including PS concentration, Fe0 dosage and pH, were investigated through a series of kinetic experiments. When the Fe0 dosage was 5.0 mM, the initial ratio of [PS]: [BAC] was 10:1, the degradation efficiency could achieve 91.7% at pH 7.0 within 60 min. Common inorganic anions and humic acid did not significantly affect BAC degradation, implying that Fe0/PS system had a potential application prospect in the actual wastewater remediation. Based on the electron paramagnetic resonance test and quenching experiments, the BAC degradation was found to be contributed by •OH, SO4•- and Fe(IV). A total of 23 intermediates were identified by the liquid chromatography-mass spectrometry, and the degradation pathways were proposed accordingly, including dealkylation and demethylation, hydroxylation, sulfate substitution and benzyl C-N cleavage reactions. Density functional theory based calculations were conducted to realize the rationality of the proposed reaction mechanisms. The toxicity of transformation products was predicted by ECOSAR program. This work demonstrated the possibility of BAC removal in hospital and municipal wastewater by Fe0/PS treatment, and also provides a safe choice for deep treatment of quaternary ammonium salt wastewater.


Assuntos
Compostos de Benzalcônio , Ferro , Poluentes Químicos da Água , Compostos de Benzalcônio/química , Cinética , Poluentes Químicos da Água/química , Ferro/química , Sulfatos/química , Águas Residuárias/química
2.
Int J Biol Macromol ; 273(Pt 1): 132809, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825296

RESUMO

Developing cost-effective and efficient adsorbents for heavy metals in multicomponent systems is a challenge that needs to be resolved to meet the challenges of wastewater treatment technology. Two adsorbents were synthesized, characterized, and investigated for the removal of Cd2+ and Cr3+ as model heavy metals in their single and binary solutions. The first adsorbent (ACZ) was a nanocomposite formed of O-Carboxymethyl chitosan, sodium alginate, and zeolite. While, the other (ACL) contained ZnFe layered double hydroxides instead of the zeolite phase. Adsorbents were characterized using XRD, FTIR, SEM, and swelling degree analysis. For single heavy metal adsorption isotherms, data for both adsorbents was best fitted and indicated a multilayer adsorption nature. For binary adsorption, Langmuir model with interacting parameters showed the best results compared to other models for both pollutants. For single system, Avrami model was found to be the best model representing the adsorption kinetics data, which indicates that the mechanism of adsorption follows multiple kinetic orders that may change during duration of adsorption process. Numerous interaction mechanisms can occur between the heavy metals and functional groups in the synthesized hydrogels such as NH2, COOH, and OH groups leading to efficient adsorption of metal ions.


Assuntos
Alginatos , Cádmio , Quitosana , Cromo , Hidrogéis , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Quitosana/análogos & derivados , Alginatos/química , Cádmio/química , Cádmio/isolamento & purificação , Adsorção , Cromo/química , Cromo/isolamento & purificação , Hidrogéis/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Cinética , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Íons/química
3.
Sci Rep ; 14(1): 3990, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368467

RESUMO

Fluoxetine (FLX) is one of the most persistent pharmaceuticals found in wastewater due to increased use of antidepressant drugs in recent decades. In this study, a nanocomposite of ternary ZnCoAl layered double hydroxide supported on activated carbon (LAC) was used as an adsorbent for FLX in wastewater effluents. The nanocomposite was characterized using Fourier Transform Infrared Spectroscopy (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and surface area analysis (BET). The adsorption investigations showed that the maximum removal capacity was achieved at pH 10, with a 0.1 g/L adsorbent dose, 50 mL volume of solution, and at a temperature of 25 °C. The FLX adsorption process followed the Langmuir-Freundlich model with a maximum adsorption capacity of 450.92 mg/g at FLX concentration of 50 µg/mL. Density functional theory (DFT) computations were used to study the adsorption mechanism of FLX and its protonated species. The safety and toxicity of the nanocomposite formed from the adsorption of FLX onto LAC (FLX-LAC) was investigated in male albino rats. Acute toxicity was evaluated using probit analysis after 2, 6, and 24 h to determine LD50 and LD100 values in a rat model. The FLX-LAC (20 mg/kg) significantly increased and lengthened the sleep time of the rats, which is important, especially with commonly used antidepressants, compared to the pure standard FLX (7 mg/kg), regular thiopental sodium medicine (30 mg/kg), and LAC alone (9 mg/kg). This study demonstrated the safety and longer sleeping duration in insomniac patients after single-dose therapy with FLX-LAC. Selective serotonin reuptake inhibitors (SSRIs) like FLX were found to have decreased side effects and were considered the first-line mood disorder therapies.


Assuntos
Nanocompostos , Poluentes Químicos da Água , Humanos , Masculino , Animais , Ratos , Fluoxetina , Águas Residuárias , Hidróxidos/química , Antidepressivos , Nanocompostos/química , Adsorção , Cinética , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio
4.
Mol Biol Rep ; 50(12): 9951-9961, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37878206

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) have been extensively used as cell-based treatments for decades due to their anti-inflammatory, immunomodulatory, and healing abilities. The intent of our study was to determine the efficacy of MSCs in alleviating rheumatoid arthritis (RA) induced by Complete Freund's adjuvant (CFA) and to investigate the anti-inflammatory and antioxidant characteristics of MSCs. METHODS AND RESULTS: Intrapedally injecting 0.1 ml of CFA directly into the footpad of the right hind paw daily for 2 days was used to induce RA. Arthritic rats received four doses of MSCs (1 × 106 cells/rat/dose) intravenously through the lateral tail vein. Our results showed that arthritic rats treated with MSCs exhibited reduced levels of paw edema. Furthermore, arthritic rats treated with MSCs exhibited a significant decrease in the levels of RF, CRP, IL-1ß, TNF-α, IL-17 and ADAMTS-5, along with a significant increase in the levels of IL-4 and TIMP-3. Additionally, MSCs significantly reduced the expression of TGF-ß. Both the glutathione (GSH) content and antioxidant activity of GST were enhanced by MSCs, while LPO levels were suppressed. CONCLUSION: These findings provide further evidence that MSCs are valuable in treating RA, possibly due to their anti-inflammatory and anti-oxidative properties. Thus, MSCs have potential as a more effective therapeutic strategy for treating RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Células-Tronco Mesenquimais , Ratos , Animais , Antioxidantes/metabolismo , Artrite Experimental/terapia , Artrite Experimental/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Artrite Reumatoide/terapia , Artrite Reumatoide/tratamento farmacológico , Células-Tronco Mesenquimais/metabolismo
5.
Biomedicines ; 11(9)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37760826

RESUMO

Prostate cancer treatment poses significant challenges due to its varying aggressiveness, potential for metastasis, and the complexity of treatment options. Balancing the effectiveness of therapies, minimizing side effects, and personalizing treatment strategies are ongoing challenges in managing this disease. Significant advances in the use of nanotechnology for the treatment of prostate cancer with high specificity, sensitivity, and efficacy have recently been made. This study aimed to synthesize and characterize a novel Cu/Fe layer double hydroxide (LDH) nanocomposite for use as an anticancer agent to treat prostate cancer. Cu/Fe LDH nanocomposites with a molar ratio of 5:1 were developed using a simple co-precipitation approach. FT-IR, XRD, SEM, TEM, TGA, and zeta potential analyses confirmed the nanocomposite. Moreover, the MTT cell viability assay, scratch assay, and flow cytometry were utilized to examine the prospective anticancer potential of Cu/Fe LDH on a prostate cancer (PC-3) cell line. We found that Cu/Fe LDH reduced cell viability, inhibited cell migration, induced G1/S phase cell cycle arrest, and triggered apoptotic effect in prostate cancer cells. The findings also indicated that generating reactive oxygen species (ROS) formation could improve the biological activity of Cu/Fe LDH. Additionally, Cu/Fe LDH showed a good safety impact on the normal lung fibroblast cell line (WI-38). Collectively, these findings demonstrate that the Cu/Fe LDH nanocomposite exhibited significant anticancer activities against PC-3 cells and, hence, could be used as a promising strategy in prostate cancer treatment.

6.
Sci Rep ; 13(1): 7227, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142660

RESUMO

Clove and green Coffee (g-Coffee) extracts were used to synthesize green iron oxide nanoparticles, which were then used to sorb Cd2+ and Ni2+ ions out of an aqueous solution. Investigations with x-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, nitrogen adsorption and desorption (BET), Zeta potential, and scanning electron microscopy were performed to know and understand more about the chemical structure and surface morphology of the produced iron oxide nanoparticles. The characterization revealed that the main component of iron nanoparticles was magnetite when the Clove extract was used as a reducing agent for Fe3+, but both magnetite and hematite were included when the g-Coffee extract was used. Sorption capacity for metal ions was studied as a function of sorbent dosage, metal ion concentration, and sorption period. The maximum Cd2+ adsorption capacity was 78 and 74 mg/g, while that of Ni2+ was 64.8 and 80 mg/g for iron nanoparticles prepared using Clove and g-Coffee, respectively. Different isotherm and kinetic adsorption models were used to fit experimental adsorption data. Adsorption of Cd2+ and Ni2+ on the iron oxide surface was found to be heterogeneous, and the mechanism of chemisorption is involved in the stage of determining the rate. The correlation coefficient R2 and error functions like RMSE, MES and MAE were used to evaluate the best fit models to the experimental adsorption data. The adsorption mechanism was explored using FTIR analysis. Antimicrobial study showed broad spectrum antibacterial activity of the tested nanomaterials against both Gram positive (S. aureus) (25923) and Gram negative (E. coli) (25913) bacteria with increased activity against Gram positive bacteria than Gram negative one and more activity for Green iron oxide nanoparticles prepared from Clove than g-Coffee one.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio/análise , Óxido Ferroso-Férrico , Escherichia coli , Staphylococcus aureus , Metais Pesados/química , Ferro/análise , Água , Antibacterianos/química , Nanopartículas Magnéticas de Óxido de Ferro , Adsorção , Cinética , Poluentes Químicos da Água/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio
7.
ACS Omega ; 7(46): 42012-42026, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36440165

RESUMO

Chitosan has received broad consideration as an adsorbent for all pollutants because of its low cost and great adsorption potential. However, its shortcomings, including sensitivity to pH, poor thermal stability, and poor mechanical strength, limit its use. The functional groups of chitosan can be modified to enhance its performance by the grafting technique and Schiff base modification. The grafting process used acrylonitrile (Ch-g-PAN) as a monomer and potassium persulfate as an initiator. After that, the modification via preparation of the Schiff base reaction using salicylaldehyde (Ch-g-Sch I) and P-anisaldehyde (Ch-g-Sch II) was carried out. The synthesized copolymers were detailed and characterized through several spectroscopic and microscopic techniques including infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. In addition, Ch-g-Sch I and Ch-g-Sch II were applied in the removal of different metal ions such as Cu2+, Cd2+, and Cr3+. The maximum adsorption capacity of Ch-g-Sch I for Cd2+ was 183.7 mg g-1 in 24 h, while in the case of Ch-g-Sch II, the maximum adsorption capacity for Cd2+ was improved to 322.9 mg g-1 for the same time. Moreover, adsorption thermodynamic analysis displays that the all ion adsorption process was not random and the pseudo-second-order model fitted with experimental results. Finally, Ch-g-Sch I and Ch-g-Sch II were applied as designs for industrial wastewater treatment with significant efficiency.

8.
J Complement Integr Med ; 19(2): 389-398, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34109772

RESUMO

OBJECTIVES: Evaluate the association between overweight/obesity with serum gonadotropin and androgen levels in Egyptian pubertal girls. SUBJECTS AND METHODS: A case-control study carried out in "Obesity Clinic" of "Diabetes, Endocrine and Metabolism Pediatric Unit (DEMPU)", Pediatric Hospital, Cairo University. It included 40 overweight and obese girls and 40 age-matching normal weight (control) ones, aged 12-18 years. Anthropometric assessment (weight, height and hip and waist circumferences) was done, and waist/hip and BMI were calculated. Laboratory investigations: lipid profile, serum gonadotropin (LH, FSH), androgen (free and total testosterone), estradiol, insulin, and FBG were quantified, while insulin resistance (IR) was calculated. RESULTS: Hypogonadotropins (FSH and LH) and hyperandrogenaemia (total and free testosterone) were significantly prominent among obese girls. Correlation between gonadotropin, androgen and all of the studied variables, for the three studied groups (obese, overweight and control) revealed constant relations. Gonadotropin and androgens showed opposing correlations. Gonadotropin had significant negativ e correlations with the anthropometric parameters of obesity (BMI, Waist C, and W/H ratio), insulin, insulin resistance and lipid profile (triglycerides, total cholesterol and LDL), whereas androgens had significant positiv e ones. In addition, gonadotropin showed significant positiv e correlations with estradiol and HDL, while androgens showed significant negative ones. CONCLUSIONS: Overweight/obesity had no effect on the correlations between gonadotropin and androgen on one side, with the anthropometric measurements and laboratory investigations on the other one. Alterations in androgen levels occur at earlier ages than gonadotropin, among both overweight and obese girls.


Assuntos
Resistência à Insulina , Sobrepeso , Adolescente , Androgênios , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Egito , Estradiol , Feminino , Hormônio Foliculoestimulante , Humanos , Insulina , Obesidade , Testosterona , Triglicerídeos
9.
RSC Adv ; 9(56): 32544-32561, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35529712

RESUMO

Nowadays, improving the physico-chemical properties of nanomaterials to enhance their performance towards various applications is urgent. Accordingly, gamma irradiation (GI) has evolved and attracted wide attention as a promising green technique to meet this need. In the current study, a Co-Fe LDH was used as a model 2D nanomaterial and was irradiated by GI (dose = 100 kGy). The sample was characterized via XRD, FTIR, FESEM, HRTEM, hydrodynamic size, zeta potential, and BET surface area measurements. The results showed that after irradiation, the surface area of the sample increased from 83 to 89 m2 g-1. Moreover, irradiation increased its dielectric constant, dielectric loss and AC conductivity. In addition, the sample showed superparamagnetic behavior, where its saturation magnetization increased from 1.28 to 52.04 emu g-1 after irradiation. Furthermore, the adsorption capacity of the irradiated LDH towards malachite green (MG) and methylene blue (MB) as model wastewater pollutants was also studied. The exposure of LDH to GI enhanced its adsorption capacity for MG from 44.73 to 54.43 mg g-1. The Langmuir-Freundlich, Sips, and Baudu models were well suited for both MG and MB adsorption among the six fitted isotherm models. The pseudo-first and second order models fit the adsorption kinetics better than the intraparticle diffusion model for both dyes. The interaction of MB and MG with the LDH surface was further investigated in dry and aqueous solution using Grand canonical Monte Carlo and molecular dynamics simulations. These two techniques provided insight into the adsorption mechanism, which is vital to understand the adsorption process by the LDH nanosheets and their possible use in practical applications. Moreover, the Co-Fe LDH showed good antibacterial activity against both Gram-positive and Gram-negative bacteria strains. Furthermore, due to its magnetic property, the Co-Fe LDH could be simply recovered from water by magnetic separation at a low magnetic field after the adsorption process.

10.
OTO Open ; 1(2): 2473974X17707925, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30480184

RESUMO

OBJECTIVE: Laryngeal cancer is the most common type of cancer in the head and neck. Human papillomavirus (HPV) represents a group of >150 related viruses. Infection with certain types of HPV can cause some types of cancer. This study aimed to evaluate the sociodemographic and histopathologic characters of squamous cell carcinoma of the larynx and its relationship to HPV subtype 16 (HPV-16). STUDY DESIGN: Cross-sectional. SETTING: Tertiary university hospitals at 5 districts in Egypt (Minia, Cairo, Giza, Qaluobia, and Bani Seuif). SUBJECTS AND METHODS: This cross-sectional study was conducted on 50 adult patients with laryngeal cancer who were admitted at 5 tertiary care hospitals in Egypt from January 2014 through December 2014. All patients were subjected to a comprehensive preoperative assessment, histopathologic assessments of tumor biopsies, and immunohistochemical staining for HPV-16. RESULTS: HPV-16 immunostaining was positive in 9 patients (18%). A significant correlation between HPV-16 immunoreactivity and tumor grade (P < .001) was detected, with no significant correlation between HPV-16 immunoreactivity and other clinical and pathologic variables. CONCLUSION: The frequency of HPV-16 in laryngeal carcinoma is 18%, and there is significant correlation between HPV-16 and tumor grade.

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