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1.
Environ Res ; 233: 116468, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343748

RESUMO

In this work, we report on the synthesis of flower-like tungsten oxide nanoparticles (WO3 NPs) using a simple precipitation method. This paper reports a simple method for synthesizing flower-like WO3 NPs, which can be used for environmentally treating hazardous organic pollutants. The photocatalytic degradation of model artificial Orange II and Congo red was assessed under natural sunlight irradiation. The surface morphologies, crystallinity, and binding energy of the synthesized WO3 NPs were determined. The synthesized WO3 NPs exhibited good photodegradation percentages of approximately Orange II (97.6%) and Congo red dye (98.2%) after 120 min of irradiation. Furthermore, the WO3 NPs maintained their degradation ability for up to three cycles. In addition, WO3 NPs were examined in different metal ions sensing (Hg2+, Fe2+, Cu2+, Ni2+, and Cd2+) in an aqueous solution. The results showed that the WO3 NPs exhibited excellent Cd2+ ion sensing. Based on the investigations, WO3 NPs proved to be an efficient photocatalyst and hold promise as the best material for future applications in preventing water pollution.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Vermelho Congo , Cádmio , Metais , Corantes
2.
Molecules ; 28(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838869

RESUMO

This study investigated some possible mechanisms underlying the nephrotoxic effect of gold nanoparticles (AuNPs) in rats and compared the protective effects of selected known antioxidants-namely, melanin, quercetin (QUR), and α-lipoic acid (α-LA). Rats were divided into five treatment groups (eight rats per group): control, AuNPs (50 nm), AuNPs + melanin (100 mg/kg), AuNPs + QUR (200 mg/kg), and AuNPs + α-LA (200 mg/kg). All treatments were administered i.p., daily, for 30 days. AuNPs promoted renal glomerular and tubular damage and impaired kidney function, as indicated by the higher serum levels of creatinine (Cr), urinary flow, and urea and albumin/Cr ratio. They also induced oxidative stress by promoting mitochondrial permeability transition pore (mtPTP) opening, the expression of NOX4, increasing levels of malondialdehyde (MDA), and suppressing glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT). In addition, AuNPs induced renal inflammation and apoptosis, as evidenced by the increase in the total mRNA and the cytoplasmic and nuclear levels of NF-κB, mRNA levels of Bax and caspase-3, and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Treatment with melanin, QUR, and α-lipoic acid (α-LA) prevented the majority of these renal damage effects of AuNPs and improved kidney structure and function, with QUR being the most powerful. In conclusion, in rats, AuNPs impair kidney function by provoking oxidative stress, inflammation, and apoptosis by suppressing antioxidants, promoting mitochondrial uncoupling, activating NF-κB, and upregulating NOX4. However, QUR remains the most powerful drug to alleviate this toxicity by reversing all of these mechanisms.


Assuntos
Nanopartículas Metálicas , Ácido Tióctico , Ratos , Animais , Antioxidantes/farmacologia , Ouro/farmacologia , Ácido Tióctico/farmacologia , NF-kappa B/metabolismo , Melaninas/metabolismo , Rim , Estresse Oxidativo , Glutationa/metabolismo , Quercetina/farmacologia , Inflamação/tratamento farmacológico
3.
Molecules ; 28(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36677854

RESUMO

This study examined the effect of gold nanoparticles (AuNPs) on doxorubicin (DOX)-induced liver damage and steatosis in rats and tested its effect mechanism. Wistar male rats were divided into four groups (each of eight rats) as control, AuNPs (50 µL of 10 nm), DOX (15 mg/kg; 3 mg/kg/week), and DOX + AuNPs-treated rats. DOX is known to induce fasting hyperglycemia and hyperinsulinemia in treated rats. Individual treatment of both DOX and AuNPs also promoted liver damage, increased circulatory levels of ALT and AST, and stimulated serum and liver levels of TGs, CHOL, LDL-c, and FFAs. They also stimulated MDA, TNF-α, and IL-6, reduced GSH, SOD, HO-1, and CAT, upregulated mRNA levels of Bax and caspases-3 and -8 and downregulated mRNA levels of Bcl2 in the livers of rats. However, while DOX alone reduced hepatic levels of PPARα, both AuNPs and DOX stimulated mRNA levels of SREBP1, reduced the mRNA, cytoplasmic and nuclear levels of Nrf2, and increased mRNA, cytoplasmic, and nuclear levels of NF-κB. The liver damage and the alterations in all these parameters were significantly more profound when both AuNPs and DOX were administered together. In conclusion, AuNPs exaggerate liver damage, hyperlipidemia, and hepatic steatosis in DOX-treated rats by activating SREBP1 and NF-κB and suppressing the Nrf2/antioxidant axis.


Assuntos
Fígado Gorduroso , Hiperlipidemias , Nanopartículas Metálicas , Ratos , Masculino , Animais , Ouro/farmacologia , Estresse Oxidativo , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Wistar , NF-kappa B/metabolismo , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/metabolismo , Fígado , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/metabolismo , Doxorrubicina/farmacologia
4.
Nutrients ; 14(16)2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-36014833

RESUMO

This study examined if regulating the keap-1? Nrf2 antioxidant pathway mediated gold nanoparticles (AuNPs) induced liver damage, and examined the protective effect of co-supplement of α-lipoic acid (α-LA). Rats were separated into 4 groups (n = 8/each) as control, α-LA (200 mg/kg), AuNPs (5 µg/2.85 × 1011), and AuNPs (5 µg/2.85 × 1011) + α-LA (200 mg/kg). After 7 days, AuNPs induced severe degeneration in the livers of rats with the appearance of some fatty changes. In addition, it increased serum levels of alanine aminotransferase (ALT) and gamma-glutamyl transferase (É£-GTT), and aspartate aminotransferase (AST), as well as liver levels of malondialdehyde (MDA). Concomitantly, AuNPs significantly depleted hepatic levels of total glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) but increased hepatic levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). It also reduced mRNA levels of B-cell lymphoma 2 (Bcl2) and heme oxygenase-1 (HO-1) but significantly increased those of Bax and cleaved caspase-3, as well as the ratio of Bax/Bcl2. In addition, AuNPs enhanced the total and nuclear levels of NF-κB p65 but reduced the mRNA and total and nuclear protein levels of Nrf2. Of note, AuNPs did not affect the mRNA levels of keap-1. All these events were reversed by α-LA in the AuNPs-treated rats. In conclusion, α-LA attenuated AuNPs-mediated liver damage in rats by suppressing oxidative stress and inflammation, effects that are associated with upregulation/activation of Nrf2.


Assuntos
Nanopartículas Metálicas , Ácido Tióctico , Animais , Glutationa/metabolismo , Ouro/metabolismo , Ouro/farmacologia , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo , Ratos , Ácido Tióctico/farmacologia , Proteína X Associada a bcl-2/metabolismo
5.
Saudi Med J ; 39(7): 719-724, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29968896

RESUMO

OBJECTIVES: To assess the usefulness of periapical dental radiograph as a screening tool aimed at early signs of osteoporosis in postmenopausal periodontal patients  and root surface evaluation using spectrochemical analysis. Methods: This study was conducted at the Department of Periodontics, Riyadh Elm University, Riyadh, Saudi Arabia, for 12 months between December 2016 and November 2017. Two groups consisted healthy postmenopausal women having chronic periodontitis and postmenopausal women having chronic periodontitis with osteoporosis. Osteoporosis were evaluated for plaque index (PI); gingival index (GI); clinical attachment level (CAL); probing pocket depth (PPD), and bone mineral density (BMD). A standardized digital dental periapical radiographs were taken for every patient. The spectrochemical analysis was carried out using the self-assembled Laser-Induced Breakdown Spectroscopy (LIBS) system used for qualitative and quantitative analysis of Calcium (Ca), Potassium (K), Phosphorus (P), Fluoride (F), and Magnesium (Mg). Results: There was no statistically significant difference between both groups for GI and PI. Similarly PPD and CAL were showing the difference but statistically, significant difference was only for CAL. Value of distance starting from cement enamel junction to the alveolar crest (CEJ-AC) and BMD were having a statistically significant variance between both groups. The differences between osteoporotic and control group were statistically significant regarding Ca with the mean higher in the control group. Furthermore, the variances between the groups in both K and Mg were statistically significant with higher mean in the osteoporotic group (p less than 0.05).  Conclusion: The clinical, radiographic, and experimental findings of this study indicated that osteoporosis has a direct effect on the progression rate of periodontal tissue destruction and dental radiographic can be suggested as a screening tool for an early sign of osteoporosis.


Assuntos
Periodontite Crônica/diagnóstico por imagem , Osteoporose Pós-Menopausa/diagnóstico por imagem , Radiografia Dentária/métodos , Raiz Dentária/química , Idoso , Densidade Óssea , Cálcio , Periodontite Crônica/epidemiologia , Periodontite Crônica/fisiopatologia , Comorbidade , Índice de Placa Dentária , Feminino , Fluoretos , Bolsa Gengival , Humanos , Magnésio , Programas de Rastreamento , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Índice Periodontal , Fósforo , Pós-Menopausa , Potássio , Arábia Saudita , Análise Espectral
6.
Biomed Res Int ; 2013: 590730, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23781503

RESUMO

The data on the biocompatibility of naked gold nanoparticles (GNPs) are scarce, and their interpretation is controversial. We studied the acute (1 day) and subchronic (5 days) effects of GNPs (10 and 50 nm diameter) on expression of interleukin-1 beta (IL-1 ß ), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF- α ) in the liver and kidneys of rats. In the liver, the GNPs of both sizes (10 and 50 nm) significantly increased the cytokines gene expression on day 1 which was subsided on day 5; the GNPs of 50 nm size produced more severe inflammatory response as compared to smaller sized GNPs. In the kidney, the GNPs did not produce any significant change in the expression of IL-1 ß . Although the gene expression of IL-6 and TNF- α was not affected by GNPs of 10 nm size, 50 nm GNPs significantly increased the expression of IL-6 and TNF- α in the kidneys of rats on day 1 after treatment which returned to normalcy on day 5. These findings indicate the possible immunocompatibility of medium sized GNPs as they caused only a transient acute phase increase in proinflammatory cytokines expression followed by their normalcy during the repeated exposure.


Assuntos
Citocinas/genética , Regulação da Expressão Gênica , Ouro/química , Mediadores da Inflamação/metabolismo , Rim/metabolismo , Fígado/metabolismo , Nanopartículas Metálicas/química , Animais , Citocinas/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo
7.
Saudi J Biol Sci ; 19(4): 461-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23961207

RESUMO

We studied the effect of gold nanoparticles (NPs) on oxidative stress markers including reduced glutathione (GSH) and malondialdehyde (MDA) in different organs of rats. Adult male Wistar-Kyoto rats were randomly divided into 3 groups of 5 animals each. One group served as control and received vehicle only. The remaining two groups were treated with 50 µl of 10 nm sized gold NPs, daily for 3 and 7 days, respectively. The rats were sacrificed 24 h after the last injection of NPs. Administration of gold NPs did not cause any significant change in GSH levels in liver, lung and heart on day 3 or day 7. There was no significant effect of gold NPs on MDA levels in lung and heart whereas significant increases in MDA levels were found in the liver of rats treated with gold nanoparticles on both 3 and 7 days post-dosing (ANOVA F = 7.113, P = 0.010). In conclusion, the findings of this preliminary study suggest that gold NPs of 10 nm diameter produce significant lipid peroxidation in rat liver however lungs and heart do not show any oxidative stress. Further studies are warranted to examine the effects of a broader dose range of gold NPs on the levels of free radical indices in different organs of rats.

8.
Ann Saudi Med ; 31(3): 311-3, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21242641

RESUMO

We report the case of a child who presented with a subcutaneous mass on the left side of the chest wall of one month's duration. The mass was painful and increasing in size over time. He had a history of weight loss and a decrease in appetite, but no history of fever or trauma. He had ingested raw camel milk, but had no history of contact with animals. He was diagnosed by the standard tube agglutination titer and tissue culture for brucellosis, treated with surgery and three months of antibrucella antibiotics. The report includes a brief review of the current pediatric literature to familiarize pediatricians with this uncommon presentation.


Assuntos
Brucelose/patologia , Leite/microbiologia , Parede Torácica/patologia , Testes de Aglutinação , Animais , Antibacterianos/uso terapêutico , Apetite , Brucelose/diagnóstico , Brucelose/terapia , Camelus , Criança , Humanos , Masculino , Redução de Peso
9.
Int J Health Sci (Qassim) ; 5(1): 81-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22489233

RESUMO

OBJECTIVE: To report on two cases of neurobrucellosis with different presentations. METHOD: Retrospective report of the data on 2 cases of neurobrucellosis: the first case presented with acute meningo-encephalitis and the second case presented with acute meningitis. RESULT: Both cases had indolent fever for more than a month. The first case presented acutely with a diffuse maculopapular rash all over the body for 1 day prior to admission and a sudden deterioration of the level of consciousness, weakness, and generalized tonic-clonic convulsions lasting for 2 minutes. The history of the presenting illness indicated a strong history of contact with animals and animal products. The second case was presented to our hospital with history of fever on and off for 2 months and 1-day history of headache and neck pain, but no history of vomiting, convulsion, or loss of consciousness. Both cases were diagnosed by the serum agglutination test and cerebrospinal fluid Brucella culture. Both cases were treated for 6 months with combination therapy of anti-Brucella drugs with excellent outcome. CONCLUSION: These are rare and serious presentations of this common public health problem, unless the physician has a high index of suspicion, morbidity and mortality will not be prevented. So, the description of both cases and a brief review of the current pediatric literature are provided to familiarize pediatricians with the relatively rare presentations of this common worldwide disease.

10.
Lipids Health Dis ; 9: 26, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20214825

RESUMO

BACKGROUND: The most important function of collagen and elastin is to induce several mechanical parameters which are known to play a dominant role in governing mechanical properties of the blood vessels. The aortic tissue of rabbit is one of the important sources of collagen and elastin. The effects of high fat diet (HFD) on the hydroxyproline (Hyp) fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits have not been documented before. The present study was undertaken to investigate the changes in Hyp fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits during the progression of atherosclerosis. The atherosclerotic model used in this study was the New Zealand white rabbit (male; 12 weeks old). Twenty five rabbits were individually caged, and divided into control group (NOR; n = 10) and HFD group (CHO; n = 15). The control group was fed (100 g/day) of normal (NOR) diet for a period of 15 weeks. The HFD group was fed normal diet supplemented with 1.0% cholesterol plus 1.0% olive oil (100 g/day) for the same period of time. RESULTS: We found that the TC, LDLC, and TG (mg/dl) were significantly (p < 0.001) increased in HFD rabbits compared with control rabbits with percentage normalized changes of 1198%, 1591%, and 710%, respectively. The peptide-bound Hyp in the serum was significantly (P < 0.05) increased in HFD rabbits compared with control rabbits with percentage normalized change of 517% while it significantly (P < 0.01) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 65%. The protein-bound Hyp in the serum was significantly (P < 0.01) increased in HFD rabbits compared with control rabbits with percentage normalized change of 100%; the protein-bound Hyp in the aortic tissues of control rabbits was 235.30 +/- 55.14 (Mean +/- SD) while it was not detectable (ND) in HFD rabbits. Total serum Hyp showed no significant (P < 0.05) change in HFD rabbits compared with control rabbits while it was significantly (P < 0.05) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 73%. The total collagen was significantly (p < 0.01) decreased in aortic tissues of HFD rabbits compared with control rabbits with percentage normalized change of 73% which was supported by histological study. CONCLUSIONS: These results suggest that percentage decrease in various Hyp fractions in aortic tissue of HFD rabbits are closely related to percentage decrease of collagen content in aortic tissues of HFD rabbits. These results also suggest that it may be possible to use the changes in various Hyp fractions in aortic tissues of rabbits as an important risk factor during the progression of atherosclerosis.


Assuntos
Aorta/fisiopatologia , Aterosclerose/metabolismo , Hidroxiprolina/farmacologia , Animais , Aorta/metabolismo , Aterosclerose/patologia , Colesterol/química , LDL-Colesterol/metabolismo , Colágeno/metabolismo , Gorduras na Dieta , Modelos Animais de Doenças , Progressão da Doença , Hidroxiprolina/metabolismo , Masculino , Azeite de Oliva , Óleos de Plantas/química , Coelhos , Artérias Torácicas/patologia , Triglicerídeos/metabolismo
11.
Bioinform Biol Insights ; 2: 95-100, 2008 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-19812768

RESUMO

Hypercholesterolemia and hypertriglyceridemia are considered as important risk factors during the atherosclerotic process. The aim of the present investigation was to study the total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), high density lipoprotein (HDL), triglyceride (TG), platelet levels and hydroxyproline fractions during the pathogenesis of atherosclerosis. For this purpose, twenty five 12-weeks, New Zealand white male rabbits, were purchased, individually caged, and divided into either control group or cholesterol-fed group. The control group (n = 10) was fed 100 g/day of normal diet, ORC-4 (Oriental Yeast Co. Ltd., Tokyo, Japan) for a period of 15 weeks. The cholesterol-fed group (n = 15) was fed a high cholesterol and saturated fat diet of ORC-4 containing 1% cholesterol plus 1% olive oil (100 g/day) for periods of 5 (group 1), 10 (group 2) and 15 (group 3) weeks. Blood sample from each animal was taken at the end of the experimental period for the biochemical analysis. The results of the present study showed that TC, LDLC, TG, HDLC and platelets were significantly (P < 0.01) increased in cholesterol-fed rabbits as compared with control rabbits. The serum hydroxyproline (Hyp) in rabbits belonging to group 1 showed no significant alteration when compared to control group. Group 2 rabbits showed a significant increase of 103% (P < 0.01) and 100% (P < 0.001) in free and protein-bound hydroxyproline fractions respectively when compared to control rabbits. However, there was no significant change in peptide-bound and total serum hydroxyproline levels as compared to the control group (P > 0.05). There was no significant (P > 0.05) decrease of free serum hydroxyproline in group 3 rabbits when compared to control rabbits. On the other hand, group 3 rabbits showed a significant increase in peptide-bound and protein-bound Hyp by 517% (P < 0.05) and 100% (P < 0.01) respectively when compared to control rabbits. However, total serum Hyp in group 3 rabbits showed no significant (P > 0.05) change when compared to control rabbits. These results suggest that feeding rabbits high cholesterol and saturated fat diet for feeding periods of 5, 10 and 15 weeks induced significant change in TC, LDLC, HDL, TG, platelet levels and various Hyp fractions in serum without any significant change in the total Hyp content.

12.
Indian J Biochem Biophys ; 43(3): 186-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16967909

RESUMO

The potential use of liposomes as a delivery system is still limited by the poor understanding of their interaction mechanisms with biological media. In the present work, interaction between bovine albumin (BA) and liposomes was studied using phase transition and dielectric measurements as well as solubilization process using non-ionic detergent octylglucoside (OG). After liposomes were incubated with diluted and concentrated BA, phase transition, characterizing the liposome membrane exhibited a shift towards higher temperatures, together with initiation of multiple phase transitions. The relaxation time of liposome membrane molecules also increased in a concentration-dependent manner. The solubilization profiles of incubated samples also showed remarkable changes, especially in beginning of solubilization stages. Moreover, amount of detergent needed to completely solubilize membrane was also increased. It was concluded that BA significantly altered the physical state of liposome membrane, which may be attributed to BA interaction with liposomes surface and/or by its incorporation within the bilayer membrane.


Assuntos
Albuminas/química , Lipossomos/química , Animais , Fenômenos Biofísicos , Biofísica , Bovinos , Sistemas de Liberação de Medicamentos , Eletroquímica , Glucosídeos , Técnicas In Vitro , Solubilidade , Termodinâmica
13.
Nahrung ; 48(2): 95-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15146964

RESUMO

The effects of gamma-irradiation on the biophysical and morphological properties of corn plants were investigated. The irradiation doses were 0, 1, 1.5, 2.5, 5, and 10 krad. Corn grains exposed to 1.5 and 2.5 krad showed highly significant changes in all growth parameters. Fluorescence and light absorption spectra of chlorophyll attributed to different doses treatments of corn grains clearly confirmed the superiority of 1.5 krad irradiation dose in stimulating corn plants. Furthermore, the frequency dependence of the relative permittivity and the electric conductivity of the treated samples have been performed and discussed. The obtained results give another support via the biophysical properties for the 1.5 krad irradiation dose to be the most favorable one to improve the plant growth characteristics.


Assuntos
Irradiação de Alimentos , Zea mays/crescimento & desenvolvimento , Zea mays/efeitos da radiação , Clorofila/metabolismo , Relação Dose-Resposta à Radiação , Condutividade Elétrica , Raios gama
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