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1.
Small ; : e2406332, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39358947

RESUMO

Herein, P2-type layered manganese and ruthenium oxide is synthesized as an outstanding intercalation cathode material for high-energy density Na-ion batteries (NIBs). P2-type sodium deficient transition metal oxide structure, Na0.67Mn1-xRuxO2 cathodes where x varied between 0.05 and 0.5 are fabricated. The partially substituted main phase where x = 0.4 exhibits the best electrochemical performance with a discharge capacity of ≈170 mAh g-1. The in situ X-ray Absorption Spectroscopy (XAS) and time-resolved X-ray Diffraction (TR-XRD) measurements are performed to elucidate the neighborhood of the local structure and lattice parameters during cycling. X-ray photoelectron spectroscopy (XPS) revealed the oxygen-rich structure when Ru is introduced. Density of States (DOS) calculations revealed the Fermi-Level bandgap increases when Ru is doped, which enhances the electronic conductivity of the cathode. Furthermore, magnetization calculations revealed the presence of stronger Ru─O bonds and the stabilizing effect of Ru-doping on MnO6 octahedra. The results of Time-of-flight secondary-ion mass spectroscopy (TOF-SIMS) revealed that the Ru-doped sample has more sodium and oxygenated-based species on the surface, while the inner layers mainly contain Ru-O and Mn-O species. The full cell study demonstrated the outstanding capacity retention where the cell maintained 70% of its initial capacity at 1 C-rate after 500 cycles.

2.
Reprod Biomed Online ; 48(5): 103778, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38492417

RESUMO

RESEARCH QUESTION: Does dexpanthenol work as an effective therapeutic agent against cyclophosphamide (CYC)-induced premature ovarian failure (POF) in rats? DESIGN: A total of 28 female Wistar Albino rats were randomly divided into four groups (n = 7 per group). The POF and POF plus dexpanthenol groups were intraperitoneally administered CYC at an initial dose of 50 mg/kg, followed by 8 mg/kg for 14 days. The dexpanthenol and POF plus dexpanthenol groups were both intraperitoneally administered dexpanthenol at a dose of 500 mg/kg/day for 15 days. RESULTS: In the group administered CYC, the following was observed: a decrease in the ovarian index; a decrease in the numbers of primordial, primary, secondary and antral follicles; an increase in the number of corpus luteum and atretic follicles; a decrease in proliferation cell nuclear antigen immunoreactivity; a significant reduction in anti-Müllerian hormone and oestradiol levels; and an increase in serum FSH levels compared with controls. Dexpanthenol, on the other hand, reversed these effects. Quantitative reverse transcription polymerase chain reaction analyses showed that dexpanthenol increased Bcl-2, Akt1, mTOR, Nrf2 and HO-1 in CYC-induced ovarian tissues, but decreased Bax, Cas3, Hsp27, Hsp70, and Hsp90. Dexpanthenol treatment has a potential for inhibiting the intrinsic apoptotic pathway and oxidative stress levels in ovarian tissues via the downregulation of the mRNA expression of heat shock proteins and the activation of Nrf2/HO-1 pathways. CONCLUSIONS: Our findings demonstrated that dexpanthenol is an effective agent against POF caused by CYC; however, further experimental and clinical data are needed to use it effectively.


Assuntos
Ciclofosfamida , Ovário , Ácido Pantotênico , Insuficiência Ovariana Primária , Ratos Wistar , Animais , Feminino , Ciclofosfamida/toxicidade , Ciclofosfamida/efeitos adversos , Ácido Pantotênico/análogos & derivados , Ácido Pantotênico/farmacologia , Ovário/efeitos dos fármacos , Ovário/patologia , Insuficiência Ovariana Primária/induzido quimicamente , Ratos , Folículo Ovariano/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Hormônio Foliculoestimulante/sangue , Serina-Treonina Quinases TOR/metabolismo , Hormônio Antimülleriano/sangue
3.
Drug Chem Toxicol ; 46(3): 566-574, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35502492

RESUMO

Isorhamnetin is a hepatoprotective flavonoid molecule derived from the leaves and fruits of Hippophae rhamnoides L. However, the protective effect of isorhamnetin on acetaminophen (APAP) induced hepatotoxicity is still unknown. Thus, we aimed to investigate the lipid-lowering, anti-inflammatory, and hepatoprotective effects of isorhamnetin on APAP-induced hepatotoxicity in mice. Hepatotoxicity was induced by a single injection of APAP (300 mg/kg, intraperitoneally). Isorhamnetin (50 or 100 mg/kg, orally) and N-acetylcysteine (NAC) (200 mg/kg, orally), or vehicle control, were administered 1 h before the administration of APAP. Total antioxidant status (TAS) and total oxidative status (TOS) of liver tissue and levels of inflammatory factors (TNF-α, IL-1ß, and IL-6) were analyzed by ELISA. Lipid profiles and liver function parameters were measured using an autoanalyzer. In addition, liver tissue was examined histopathologically. Isorhamnetin treatment significantly reduced the APAP-induced increase in the liver weight and liver index; it also reduced the APAP-induced increase in serum liver parameters (ALT, AST, ALP, and LDH) (p < 0.05). Isorhamnetin significantly reduced APAP-induced oxidative stress and inflammation by increasing TAS levels and decreasing TOS, TNF-α, IL-1ß, and IL-6 levels (p < 0.05). Moreover, isorhamnetin treatment significantly regulated lipid profiles (TG, T-C, LDL-C, and HDL-C levels) that changed in response to APAP administration (p < 0.05). In histopathological examination, liver degeneration observed in the APAP group was significantly reduced in the NAC and isorhamnetin-treated groups (p < 0.05). This study suggests that isorhamnetin has a significant protective effect on APAP-induced hepatotoxicity in mice through its lipid-lowering, antioxidant, and anti-inflammatory effects.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Camundongos , Animais , Acetaminofen/toxicidade , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6 , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Anti-Inflamatórios/farmacologia , Fígado , Estresse Oxidativo , Acetilcisteína/farmacologia , Camundongos Endogâmicos C57BL , Lipídeos
4.
Bull Environ Contam Toxicol ; 109(6): 1150-1154, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35997791

RESUMO

This study aims to describe a simple and environmentally friendly procedure for producing silver nanoparticles (AgNPs) using Paeonia kesrouanensis (P. kesrouanensis) extracts and to determine the toxic effect in the aquatic environment. The morphologies, size, size distributions, and structural properties were analyzed using SEM-EDX, TEM, DLS, zeta potential, FTIR, and XRD. AgNPs were applied to Artemia salina (A.salina), aquatic organism individuals at 7 different concentrations (0.0, 0.2, 1, 5, 10, 25, 50 mg/L) for 24, 48, and 72 h. AgNPs accumulation and elimination, ion release amounts, and the survival rates of organisms were determined at periods of 24, 48, and 72nd hours. The highest accumulation was observed at the 24th hour at the 50 mg/L exposure level. The survival rate decreased as exposure time increased at all concentrations.


Assuntos
Nanopartículas Metálicas , Paeonia , Humanos , Animais , Artemia , Prata/toxicidade , Prata/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Extratos Vegetais/química
5.
Ecotoxicol Environ Saf ; 208: 111774, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396089

RESUMO

Aflatoxins (AFs) are metabolised in two main phases in the liver. Cytochrome p450 enzyme (CYP) 1A1 and CYP2A6 are expressed through AhR, CAR and PXR nuclear receptors in phase-1 biotransformation of AFs. This study is the first to examine phase-1 biotransformation mechanisms of AF and the activity of Nigella sativa seed (NS) and its active ingredient thymoquinone (TQ) on these enzymes and receptors at the molecular level in broilers. Six groups of one day old broiler chicken (20 animals per group) were fed either control feed or a diet containing Aspergillus parasiticus NRRL 2999 culture material (total AFs 2 mg/kg), TQ (300 mg/kg), and NS (5%), either alone or as AF + TQ and AF + NS. Randomly selected from each group, 10 chicks were necropsied, and the livers were removed. Histopathological examination and serum biochemistry results revealed that AF caused hydropic and fatty degenerations, periportal inflammatory infiltrations, acinar arrangement, and biliary duct proliferation in livers and a significant increase at AST, ALT, ALP and GGT levels while significant decreases at serum cholesterol and total protein levels. These aflatoxicosis lesions and deteriorations in biochemistry levels were significantly ameliorated by NS or TQ (p < 0.05). AF was immunohistochemically found to increase strongly the nuclear receptors of AhR, PXR, CAR, and the enzyme activity of CYP1A1 and CYP2A6 responsible for its metabolism, leading to the emergence of toxic effects. Addition of TQ or NS to AF-containing diets improved the negative effects of AF on these receptors and enzymes significantly (p < 0.05). It was concluded that TQ and NS successfully alleviated liver injury by inhibiting or reducing the bioactivation of AF through phase-1 nuclear receptors and CYP-450 enzymes modulation.


Assuntos
Aflatoxinas/toxicidade , Galinhas/fisiologia , Nigella sativa/fisiologia , Aflatoxinas/metabolismo , Animais , Aspergillus , Benzoquinonas , Sistema Enzimático do Citocromo P-450/metabolismo , Dieta , Fígado/efeitos dos fármacos , Nigella sativa/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Sementes
6.
Int J Neurosci ; : 1-7, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33650929

RESUMO

OBJECTIVES: This study was designed to investigate the possible antioxidant, antiapoptotic and neuroprotective effects of nobiletin on cisplatin-induced neurotoxicity rat model by evaluating neurotrophins, antioxidants and histopathology. METHODS: Forty male Wistar Albino rats were divided into four groups: control, cisplatin (CIS), cisplatin + nobiletin (CIS + NOB) and nobiletin + cisplatin (NOB + CIS). CIS + NOB was applied nobiletin (10 mg/kg, i.p.) during the last four days whereas NOB + CIS was applied nobiletin during the first four days of the study. Cisplatin (4 mg/kg, i.p. twice a day) was administered to the experimental groups on the 5th day of the study. All rats were sacrificed on the 10th day of the study. BDNF, NGF, G6PD, GPx, tGSH and MDA levels were determined in brain. In addition, routin histolopathological analysis and caspase-3 immunoreactivity assay were conducted. RESULTS: BDNF concentrations increased in nobiletin-administered groups, compared to Control and CIS and that the increase was statistically significant in NOB + CIS (p < 0.05). It was also found that G6PD activity increased (p < 0.05) in the nobiletin-administered groups, compared to control and CIS. Histopathologically, neuronal degeneration, oedema and gliosis increased in CIS compared to Control, and nobiletin administration decreased neuronal degeneration and oedema compared to CIS (p < 0.05). Cisplatin increased (p < 0.05) caspase-3 immunoreactivity in cerebrovascular endothelium and neurons compared to Control, while nobiletin administration decreased caspase-3 immunoreactivity in cerebrovascular endothelium. Caspase-3 immunoreactivity in neurons decreased only in NOB + CIS (p < 0.05). CONCLUSION: Nobiletin increased BDNF concentration and G6PD activity in brain and when evaluated together with histopathological and immunohistochemical findings, it may have antioxidant, antiapoptotic and neuroprotective effects against cisplatin.

7.
Environ Toxicol ; 35(3): 385-394, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31709674

RESUMO

In this study, the impact of alpha-iron oxide (α-Fe2 O3 , 20-40 nm) and gamma iron oxide (γ-Fe2 O3 , 20-40 nm) nanoparticles (NPs) on phytoplankton species Selenastrum capricornutum and Nannochloropsis oculata was investigated Characterizations of the NPs were systematically carried out by TEM, dynamic light scattering, zeta potential, X-ray diffraction, SEM, and Fourier transformation infrared spectroscopy. Acute toxicity was tested between 0.2 and 50 mg/L for each NP for a period of 72 hours exposure. γ-Fe2 O3 NP inhibited development of N oculata at the rate of 54% in 0.2 mg/L group with a high mortality rate of up to 82%. α-Fe2 O3 NPs were less toxic that induced 97% mortality on N oculata at 10 mg/L suspensions. In contrast, α-Fe2 O3 NP inhibited growth of S capricornutum strongly (73%) in 0.2 mg/L group. γ-Fe2 O3 NPs showed similar growth inhibition (72%) on S capricornutum in 10 mg/L suspensions. Despite the differential effects, the results indicated acute toxicity of α-Fe2 O3 and γ-Fe2 O3 NPs on N oculata and S capricornutum.


Assuntos
Clorófitas/efeitos dos fármacos , Compostos Férricos/toxicidade , Nanopartículas Metálicas/toxicidade , Fitoplâncton/efeitos dos fármacos , Estramenópilas/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Bull Environ Contam Toxicol ; 104(2): 206-214, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31748865

RESUMO

In this study, the effect of zinc nanoparticles (Zn NPs) and zinc oxide nanoparticles (ZnO NPs) on Artemia salina and Daphnia magna, the primary consumer organisms were investigated. In this sense, investigation of trophic transfer and ecological sustainability potentials among living things, such as fish and crustaceans that are at the top of the food chain were also aimed. Zn NPs in the size of 40-60 nm and 80-100 nm and ZnO NPs (10-30 nm) were administered to A. salina and D. manga (respectively in total 105000 and 14000 individuals) in seven groups (Control, 0.2, 1, 5, 10, 25 ve 50 ppm) with three repetitions for a period of 72 h. Intensive and possible misuse of nanoscale materials is one of the biggest threats to the environment and all living things worldwide. Therefore, the control mechanisms for the use of NPs need to be established.


Assuntos
Artemia/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Zinco/toxicidade , Animais , Artemia/metabolismo , Cadeia Alimentar , Estresse Oxidativo
9.
Bull Environ Contam Toxicol ; 105(3): 372-380, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705320

RESUMO

Quantum dots (QDs), such as cadmium selenide (CdSe) and lead selenide (PbSe) exhibit excellent optical, magnetic and chemical properties due to their extremely size (ca. 1-10 nm) and are attractive semiconductor nanomaterials for optical studies and energy storage. In this study, aqueous synthesis of CdSe and PbSe QDs in a size range of 2-10 nm was described. Synthesized QDs were characterized using SEM and TEM, DLS, zeta potential, FTIR, EDX and XRD. Highest accumulation (72.5 ± 5.8 mg L-1) of PbSe QDs occurred at 10 ppm suspensions. In general accumulation increased up to 48 h exposure then fluctuate tended to decline. For CdSe QDs, accumulation tended to decrease for 72 h exposure except that for 5 ppm groups. For the elimination period, in general, the elimination levels of PbSe and CdSe QDs from exposed individuals decreased (p < 0.05) even it has some fluctuate.


Assuntos
Artemia/fisiologia , Compostos de Cádmio/toxicidade , Chumbo/toxicidade , Pontos Quânticos/toxicidade , Compostos de Selênio/toxicidade , Animais , Artemia/efeitos dos fármacos , Compostos de Cádmio/química , Compostos de Cádmio/farmacologia , Nanoestruturas , Água/química
10.
J Craniofac Surg ; 30(1): e49-e52, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30480629

RESUMO

BACKGROUND: The aim of this study is to investigate whether changes in cerebrospinal fluid (CSF) pressure during the hemodialysis (HD) treatment are reflected on tympanometric measurements. METHODS: The study was performed on 24 HD patients. The static compliance and absorbance values of the patients before and after HD were measured using a wideband tympanometry. The tympanogram tests were performed immediately before and at the end of the HD session. RESULTS: The static compliance values of the patients after HD were significantly lower than those before HD. This decrease significantly correlated with the adequacy of dialysis determined by urea reduction rate and Kt/V. The absorbance values showed a decrease in the band 343 and 727 Hz, but no significant difference was found in other frequencies. The static admittance and absorbance values were influenced by the HD process. DISCUSSION: This influence might be due to the increase in CSF pressure as a result of the removal of urea from blood during HD session.


Assuntos
Testes de Impedância Acústica , Pressão do Líquido Cefalorraquidiano , Diálise Renal , Membrana Timpânica/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Complacência (Medida de Distensibilidade) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ureia/sangue , Adulto Jovem
12.
Environ Toxicol ; 32(4): 1213-1225, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27464841

RESUMO

Zinc nanoparticles (ZnNPs) are among the least investigated NPs and thus their toxicological effects are not known. In this study, tilapia (Oreochromis niloticus) were exposed to 1 and 10 mg/L suspensions of small size (SS, 40-60 nm) and large size (LS, 80-100 nm) ZnNPs for 14 days under semi-static conditions. Total Zn levels in the intestine, liver, kidney, gill, muscle tissue, and brain were measured. Blood serum glucose (GLU), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and lactate dehydrogenase (LDH) were examined to elucidate the physiological disturbances induced by ZnNPs. Organ pathologies were examined for the gills, liver, and kidney to identify injuries associated with exposure. Significant accumulation was observed in the order of intestine, liver, kidney, and gills. Zn levels exhibited time- and concentration-dependent increase in the organs. Accumulation in kidney was also dependent on particle size; NPs SS-ZnNPs were trapped more effectively than LS-ZnNPs. No significant accumulation occurred in the brain (p > 0.05) while Zn levels in muscle tissue increased only marginally (p ≥ 0.05). Significant disturbances were noted in serum GOT and LDH (p < 0.05). The GPT levels fluctuated and were not statistically different from those of controls (p > 0.05). Histopathological tubular deformations and mononuclear cell infiltrations were observed in kidney sections. In addition, an increase in melano-macrophage aggregation intensity was identified on the 7th day in treatments exposed to LS-ZnNPs. Mononuclear cell infiltrations were identified in liver sections for all treatments. Both ZnNPs caused basal hyperplasia in gill sections. Fusions appeared in the gills after the 7th day in fish treated with 10 mg/L suspensions of SS-ZnNPs. In addition, separations in the secondary lamella epithelia were observed. The results indicated that exposure to ZnNPs could lead to disturbances in blood biochemistry and cause histopathological injuries in the tissues of O. niloticus. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1213-1225, 2017.


Assuntos
Nanopartículas Metálicas/química , Poluentes Químicos da Água/metabolismo , Zinco/química , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Glicemia/análise , Ciclídeos , Exposição Ambiental , Brânquias/química , Brânquias/efeitos dos fármacos , Brânquias/patologia , Intestinos/química , Intestinos/efeitos dos fármacos , Intestinos/patologia , Rim/química , Rim/efeitos dos fármacos , Rim/patologia , L-Lactato Desidrogenase/sangue , Fígado/química , Fígado/efeitos dos fármacos , Fígado/patologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/ultraestrutura , Músculos/química , Músculos/efeitos dos fármacos , Músculos/patologia , Tamanho da Partícula , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
13.
Community Ment Health J ; 53(4): 464-473, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28130726

RESUMO

The aim of this study was to determine the effects of the psychoeducation received by the family members of the patients with first-episode schizophrenia on the expressed emotion (EE) and the family functioning of the family members. This study has a quasi-experimental design with a control group. The sample of the study was 60 family members (30 experimental -30 control) of the patients with first-episode schizophrenia. The experimental group received 9 weeks of psychoeducation as a group. EE and family functioning were assessed at the beginning and at the end of the psychoeducation program. EE criticism/hostility and over involvement-protecting-intervention levels of the family members have decreased at the end of the psychoeducation (p < 0.05). Family functioning has changed too at the end of the psychoeducation (p < 0.05), and assessed as more healthy. Consequently, early psychoeducational groups may be effective in decreasing EE level and improving the family functioning for a family member of patient with first-episode schizophrenia.


Assuntos
Emoções Manifestas , Relações Familiares/psicologia , Educação em Saúde , Esquizofrenia/fisiopatologia , Feminino , Humanos , Masculino , Inquéritos e Questionários
14.
Clin Lab ; 62(3): 425-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27156333

RESUMO

BACKGROUND: Disintegrin-like and Metalloproteinase with Thrombospondin Motifs (ADAMTS) proteins that are fundamentally located in the extracellular matrix (ECM) have critical roles on different cellular processes by altering the ECM architecture. It has been known that expression of some members of these proteinases increases in aneurismal and dissectional aortic tissue. The purpose of this study is to investigate ADAMTS1, 5, 16 and tissue inhibitors of metalloproteinases-1, -2 (TIMP-1, -2) levels in aortic tissue obtained from patients with thoracic aortic aneurysms and dissections and to achieve new insights about the function of ADAMTS family members. METHODS: We investigated ADAMTS1, 5, and 16 expression in human thoracic aortic aneurysms (TAA) (n = 22), thoracic aortic dissections (TAD) (n = 12), and thoracic aortas from age-matched control organ donors (n = 6) (a total number of 34 cases and 6 controls). The expression levels of ADAMTS proteins were determined by Western blot technique using anti-ADAMTS1, ADAMTS5, ADAMTS16, TIMP-1 and TIMP-2 antibodies. RESULTS: ADAMTS1, 5, and 16 protein expressions were significantly higher in thoracic aortic aneurysm and dissection tissues compared to control aortic tissues. Furthermore, TIMP-1 protein levels decreased in TAA and TAD tissues, TIMP-2 did not change. CONCLUSIONS: Under the light of our findings, increased expression of ADAMTS1, 5, and 16 proteins may promote deceleration in thoracic aortic aneurysm progression. This is the first study that demonstrates ADAMTS5 and ADAMTS16 proteolytic activity in aneurysm and dissection.


Assuntos
Proteínas ADAM/análise , Aneurisma da Aorta Torácica/metabolismo , Dissecção Aórtica/metabolismo , Proteínas ADAMTS , Proteína ADAMTS1 , Proteína ADAMTS5 , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-2/análise
16.
Toxicol Ind Health ; 32(1): 39-46, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23907830

RESUMO

Acetaminophen (APAP) is widely used in the treatment of pain. Toxic doses of APAP cause acute liver failure, but therapeutic doses are believed to be safe. The purpose of this study is to investigate the effects of administration of subtoxic doses of APAP on liver and blood levels of insulin-like growth factor-1 (IGF-1) in rats. Low dose (100 mg/kg) and high dose (250 mg/kg) of APAP were intraperitoneally injected into Wistar albino rats. Following administration of therapeutic doses of APAP, there were no significant changes in serum transaminases and liver glutathione levels. Both doses of APAP induced a decrease in liver and blood levels of IGF-1 when compared with the controls. There was no significant difference in liver IGF-1 levels between the high-dose and low-dose APAP groups; however, there was a significant difference in blood IGF-1 levels between both the groups. The histological examination showed that low dose of APAP induced mild degree of structural change, while high dose of APAP induced severe structural damage. In conclusion, these results suggest that blood IGF-1 levels may have a value in predicting hepatic damage resulting from therapeutic doses of APAP.


Assuntos
Acetaminofen/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/efeitos dos fármacos , Acetaminofen/administração & dosagem , Animais , Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar
17.
J Electrochem Soc ; 162(7): A1236-A1245, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26478598

RESUMO

We report the results of a comprehensive study of the relationship between electrochemical performance in Li cells and chemical composition of a series of Li rich layered metal oxides of the general formula xLi2MnO3 · (1-x)LiMn0.33Ni0.33Co0.33O2 in which x = 0,1, 0.2, 0,3, 0.5 or 0.7, synthesized using the same method. In order to identify the cathode material having the optimum Li cell performance we first varied the ratio between Li2MnO3 and LiMO2 segments of the composite oxides while maintaining the same metal ratio residing within their LiMO2 portions. The materials with the overall composition 0.5Li2MnO3 · 0.5LiMO2 containing 0.5 mole of Li2MnO3 per mole of the composite metal oxide were found to be the optimum in terms of electrochemical performance. The electrochemical properties of these materials were further tuned by changing the relative amounts of Mn, Ni and Co in the LiMO2 segment to produce xLi2MnO3 · (1-x)LiMn0.50Ni0.35Co0.15O2 with enhanced capacities and rate capabilities. The rate capability of the lithium rich compound in which x = 0.3 was further increased by preparing electrodes with about 2 weight-percent multiwall carbon nanotube in the electrode. Lithium cells prepared with such electrodes were cycled at the 4C rate with little fade in capacity for over one hundred cycles.

18.
Environ Toxicol ; 30(1): 119-28, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24860999

RESUMO

Dietary and waterborne exposure to copper oxide (CuO) and zinc oxide (ZnO) nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects, and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP-MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a 10-fold higher accumulation in the intestine. The heart, brain, and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p ≥ 0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p < 0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions.


Assuntos
Artemia/metabolismo , Cobre/toxicidade , Carpa Dourada/metabolismo , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Animais , Cobre/farmacocinética , Relação Dose-Resposta a Droga , Comportamento Alimentar , Cadeia Alimentar , Carpa Dourada/crescimento & desenvolvimento , Malondialdeído/metabolismo , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Distribuição Tecidual , Poluentes Químicos da Água/farmacocinética , Óxido de Zinco/farmacocinética
19.
Environ Toxicol ; 30(1): 109-18, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24753078

RESUMO

In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity, and elimination of α-Al2O3 (50 nm and 3.5 µm) and γ-Al2O3 (5 nm and 0.4 µm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to >0.3 µm for spherical NPs and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images showed that NPs deposited inside the guts as aggregates. Inductively coupled plasma mass spectrometry analysis showed that large particles (3.5 µm α-Al2O3) were not taken up by Artemia, whereas fine NPs (0.4 µm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 µm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at all conditions.


Assuntos
Óxido de Alumínio/toxicidade , Artemia/efeitos dos fármacos , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Alumínio/química , Óxido de Alumínio/farmacocinética , Animais , Artemia/crescimento & desenvolvimento , Artemia/metabolismo , Relação Dose-Resposta a Droga , Ecotoxicologia , Larva , Malondialdeído/metabolismo , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Água do Mar/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacocinética , Difração de Raios X
20.
Bull Environ Contam Toxicol ; 95(6): 752-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26276558

RESUMO

The effects of alpha-iron oxide (α-Fe2O3) and gamma-iron oxide (γ-Fe2O3) nanoparticles (NPs) on marine microalgae species (Nannochloropsis sp. and Isochrysis sp.) were investigated in this study. Both Fe2O3 NPs covered the surface of algae with the agglomerates of the nanoparticles. This form of physical NP toxicity significantly decreased the sizes of phytoplankton. Both NPs were toxic to the tested algal species, while α-Fe2O3 showed less toxicity than γ-Fe2O3 NPs for both algal species. A comparative analysis of growth data of the two algal species treated with α-Fe2O3 or γ-Fe2O3 NPs revealed that Isochrysis sp. are more sensitive than Nannochloropsis sp. Toxicity of these widely used NPs to primary producers forming the base of the food chain in aquatic environments might result in widespread adverse effects on aquatic environmental health.


Assuntos
Compostos Férricos/toxicidade , Microalgas/efeitos dos fármacos , Nanopartículas/toxicidade , Fitoplâncton/efeitos dos fármacos , Compostos Férricos/química , Microalgas/fisiologia , Nanopartículas/química , Fitoplâncton/fisiologia
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