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1.
Neural Regen Res ; 17(9): 2072-2078, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35142699

RESUMO

In our previous studies, we have shown that (D-Ser2) oxyntomodulin (Oxm), a glucagon-like peptide 1 (GLP-1) receptor (GLP1R)/glucagon receptor (GCGR) dual agonist peptide, protects hippocampal neurons against Aß1-42-induced cytotoxicity, and stabilizes the calcium homeostasis and mitochondrial membrane potential of hippocampal neurons. Additionally, we have demonstrated that (D-Ser2) Oxm improves cognitive decline and reduces the deposition of amyloid-beta in Alzheimer's disease model mice. However, the protective mechanism remains unclear. In this study, we showed that 2 weeks of intraperitoneal administration of (D-Ser2) Oxm ameliorated the working memory and fear memory impairments of 9-month-old 3×Tg Alzheimer's disease model mice. In addition, electrophysiological data recorded by a wireless multichannel neural recording system implanted in the hippocampal CA1 region showed that (D-Ser2) Oxm increased the power of the theta rhythm. In addition, (D-Ser2) Oxm treatment greatly increased the expression level of synaptic-associated proteins SYP and PSD-95 and increased the number of dendritic spines in 3×Tg Alzheimer's disease model mice. These findings suggest that (D-Ser2) Oxm improves the cognitive function of Alzheimer's disease transgenic mice by recovering hippocampal synaptic function and theta rhythm.

2.
Rev Assoc Med Bras (1992) ; 65(3): 355-360, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30994833

RESUMO

OBJECT: To explore the treatment effect of the anterior medial neurovascular interval approach to coronal shear fractures of the distal humerus. METHODS: This prospective study included two female patients who were 30-64 years old, with a mean age of 47 years. Fractures were caused by falling from a bicycle. The time between the injury and operation was 1-2 days, with a mean time interval of 1.5 days. Two patients with coronal shear fracture of the distal humerus were treated with open reduction and internal fixation using anterior neurovascular interval approach. RESULTS: There were no intraoperative and postoperative neurological and vascular complications or infections, and the fracture was united. At 12 months after the surgery, the patient returned to work without pain, and with a normal range of motion for elbow and forearm rotation. The X-rays revealed excellent fracture union, no signs of heterotopic ossification, and no traumatic arthritis. According to Mayo's evaluation standards for elbow function, a score of 100 is excellent. CONCLUSIONS: The application of the anterior neurovascular interval approach of the elbow in the treatment of shear fracture of the articular surface of the distal humerus, particularly the trochlea of the humerus, can reduce the stripping of the soft tissue.


Assuntos
Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Úmero/lesões , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Feminino , Seguimentos , Humanos , Fraturas do Úmero/fisiopatologia , Úmero/fisiopatologia , Ilustração Médica , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
3.
Rev. Assoc. Med. Bras. (1992) ; 65(3): 355-360, Mar. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1003039

RESUMO

SUMMARY OBJECT: To explore the treatment effect of the anterior medial neurovascular interval approach to coronal shear fractures of the distal humerus. METHODS: This prospective study included two female patients who were 30-64 years old, with a mean age of 47 years. Fractures were caused by falling from a bicycle. The time between the injury and operation was 1-2 days, with a mean time interval of 1.5 days. Two patients with coronal shear fracture of the distal humerus were treated with open reduction and internal fixation using anterior neurovascular interval approach. RESULTS: There were no intraoperative and postoperative neurological and vascular complications or infections, and the fracture was united. At 12 months after the surgery, the patient returned to work without pain, and with a normal range of motion for elbow and forearm rotation. The X-rays revealed excellent fracture union, no signs of heterotopic ossification, and no traumatic arthritis. According to Mayo's evaluation standards for elbow function, a score of 100 is excellent. CONCLUSIONS: The application of the anterior neurovascular interval approach of the elbow in the treatment of shear fracture of the articular surface of the distal humerus, particularly the trochlea of the humerus, can reduce the stripping of the soft tissue.


RESUMO OBJETIVO: Explorar o efeito do tratamento com uma abordagem anterior do intervalo neurovascular médio para fraturas de cisalhamento coronal da porção distal do úmero. METODOLOGIA: Este estudo prospectivo incluiu duas pacientes do sexo feminino de 30-64 anos de idade, com idade média de 47 anos. As fraturas foram causadas por quedas de bicicleta. O tempo entre a lesão e a operação foi de 1-2 dias, com um intervalo de tempo médio de 1,5 dias. Duas pacientes com cisalhamento coronal da porção distal do úmero foram tratadas com redução aberta e fixação interna utilizando a abordagem anterior do intervalo neurovascular. RESULTADOS: Não houve complicações neurológicas e vasculares intra e pós-operatórias, nem complicações ou infecções, e a fratura foi unida. Após 12 meses da cirurgia, as pacientes retornaram ao trabalho sem dor e com uma amplitude normal de movimento de rotação do antebraço e cotovelo. Os raios-X revelaram excelente união das fraturas, sem sinais de ossificação heterotópica e sem artrite traumática. De acordo com as diretrizes da clínica Mayo para avaliação da função do cotovelo, uma pontuação de 100 é considerada excelente. CONCLUSÃO: A aplicação da abordagem anterior do intervalo neurovascular do cotovelo no tratamento de uma fratura de cisalhamento da superfície articular da porção distal do úmero, especificamente da tróclea do úmero, pode reduzir o desgaste do tecido mole.


Assuntos
Humanos , Feminino , Adulto , Procedimentos Cirúrgicos Vasculares/métodos , Procedimentos Neurocirúrgicos/métodos , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Úmero/cirurgia , Úmero/lesões , Fatores de Tempo , Estudos Prospectivos , Reprodutibilidade dos Testes , Seguimentos , Resultado do Tratamento , Fraturas do Úmero/fisiopatologia , Úmero/fisiopatologia , Ilustração Médica , Pessoa de Meia-Idade
4.
Biomed Res Int ; 2016: 2482086, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446944

RESUMO

To evaluate the effect of 3D printing in treating trimalleolar fractures and its roles in physician-patient communication, thirty patients with trimalleolar fractures were randomly divided into the 3D printing assisted-design operation group (Group A) and the no-3D printing assisted-design group (Group B). In Group A, 3D printing was used by the surgeons to produce a prototype of the actual fracture to guide the surgical treatment. All patients underwent open reduction and internal fixation. A questionnaire was designed for doctors and patients to verify the verisimilitude and effectiveness of the 3D-printed prototype. Meanwhile, the operation time and the intraoperative blood loss were compared between the two groups. The fracture prototypes were accurately printed, and the average overall score of the verisimilitude and effectiveness of the 3D-printed prototypes was relatively high. Both the operation time and the intraoperative blood loss in Group A were less than those in Group B (P < 0.05). Patient satisfaction using the 3D-printed prototype and the communication score were 9.3 ± 0.6 points. A 3D-printed prototype can faithfully reflect the anatomy of the fracture site; it can effectively help the doctors plan the operation and represent an effective tool for physician-patient communication.


Assuntos
Fraturas do Tornozelo , Administração de Caso , Modelos Anatômicos , Impressão Tridimensional , Inquéritos e Questionários , Adulto , Fraturas do Tornozelo/diagnóstico por imagem , Fraturas do Tornozelo/patologia , Fraturas do Tornozelo/cirurgia , Perda Sanguínea Cirúrgica/prevenção & controle , Feminino , Humanos , Masculino
5.
Environ Toxicol ; 29(6): 697-704, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22847984

RESUMO

The embryonic and postembryonic developmental toxicity of imidazolium-based ionic liquids (ILs) to the snail Physa acuta was evaluated in this study. The results of embryonic toxicity tests showed that lower concentrations of 1-octyl-3-methylimidazolium bromide ([C8 mim]Br) (1.5 and 2.1 mg/L) inhibited the hatching rate of snail embryos, and partial snails hatched normally and died, while all of the treated embryos died when the exposure concentration was higher than 4.16 mg/L, at which IL caused the deformation, death, and decay of snail embryos. Statistical analyses revealed obvious differences in the hatching rates between three developmental stages in the 2.1 and 2.94 mg/L groups, indicating that the veliger stage is more sensitive to [C8 mim]Br exposure than the blastula and gastrula stages. Furthermore, the 96 h LC50 values of [C8 mim]Br on the tested snails at three developmental stages (juvenile, subadult, and adult) were 70.83 ± 2.99, 97.59 ± 4.05, and 109.3 ± 2.22 mg/L, respectively, indicating that young snails were more sensitive to [C8 mim]Br toxicity than adults. In addition, the 96 h LC50 values of ILs with different alkyl chain lengths, that is, [C12 mim], [C10 mim], [C8 mim], and [C6 mim], in adult snails were 1.35 ± 0.24, 8.96 ± 5.66, 109.3 ± 4, and 359.6 ± 11.6 mg/L, respectively, suggesting that longer alkyl chains can increase the toxicity of imidazolium ILs on snails.


Assuntos
Boratos/toxicidade , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Caramujos/efeitos dos fármacos , Animais , Embrião não Mamífero/efeitos dos fármacos , Caramujos/embriologia , Testes de Toxicidade Aguda
6.
Environ Toxicol ; 28(4): 207-14, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21544922

RESUMO

In the present study, goldfish toxicity and superficial damage from 1-methyl-3-octylimidazolium bromide ([C8 mim]Br) exposure were evaluated by an acute toxicity test. These results show that the 24-h 50% lethal concentration for [C8 mim]Br in goldfish is 244 mg L(-1) , and this indicates that [C8 mim]Br is a chemical with moderate or low toxicity to organisms. Scanning electronic microscope and histological observations revealed that acute exposure to [C8 mim]Br induced obvious superficial damage to the skin, gill filaments, and intestinal villi of the goldfish, and this suggests that the skin, gills, and intestines may be the first direct targets of the ionic liquid in this fish. Histological examination also indicated that [C8 mim]Br-exposure caused damage to the goldfish's hepatopancreas and kidney, consisting mainly of hepatic cords in a loose connection, hepatic cytoplasmic vacuolation, renal parenchyma vacuolization, and intumescence of the renal tubule. In addition, we found that [C8 mim]Br caused a significant increase in malondialdehyde (MDA) level in the hepatopancreases from these goldfish, and thus we suggest that the MDA level may be a biomarker of [C8 mim]Br-toxicity in goldfish.


Assuntos
Carpa Dourada , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Animais , Biomarcadores/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/patologia , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Rim/efeitos dos fármacos , Rim/patologia , Dose Letal Mediana , Malondialdeído/metabolismo , Especificidade de Órgãos , Pele/efeitos dos fármacos , Pele/patologia , Testes de Toxicidade Aguda
7.
Toxicol In Vitro ; 26(7): 1087-92, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22835898

RESUMO

Ionic liquids have recently received considerable attention due to their negligible vapor pressure and substitute for conventional organic solvents. However, their solubility in water and a great deal of literature regarding their toxicity on aquatic organisms have caused much concern in recent years. This study aims to evaluate the cytotoxicity of 1-octyl-3-methylimidazolium chloride ([C(8)mim][Cl]) on the rat pheochromocytoma (PC12) cell line by cell viability assay and to determine the cytological alterations and damages in PC12 cells after 24h of exposure at the concentrations of 0.07, 0.14, and 0.28 mM of [C(8)mim][Cl]. The results show that [C(8)mim][Cl] inhibits PC12 cell growth and decreases their viabilities in a remarkable dose-dependent manner, and the 24h EC(50) of [C(8)mim][Cl] for PC12 cells is calculated to be around 0.56 mM. Our results also reveal that [C(8)mim][Cl]-exposure induces DNA damage, sustained increase of intracellular Ca(2+), overproduction of reactive oxygen species, gradually exhausted cellular ATP, mitochondrial permeability transition, and apoptosis in PC12 cells. We suppose that mitochondrial permeability transition and mitochondrial dysfunction maybe the major cytotoxicity mechanism of [C(8)mim]Cl for PC12 cells.


Assuntos
Boratos/toxicidade , Imidazóis/toxicidade , Mitocôndrias/efeitos dos fármacos , Células PC12/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Crescimento Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , DNA de Neoplasias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Mitocôndrias/metabolismo , Células PC12/metabolismo , Células PC12/patologia , Permeabilidade/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
8.
Ecotoxicol Environ Saf ; 83: 102-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22770951

RESUMO

The cytotoxicity of alkylmethylimidazolium-based ionic liquids on rat pheochromocytoma (PC12) cells was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase release (LDH), and acridine orange staining in the present study. Mitochondrial depolarization, DNA fragmentation, reactive oxygen species (ROS) levels, and caspase-3 activity were also determined. The results showed dose-dependent cytotoxicity of ionic liquids on PC12 cells, and the ionic liquids with longer lateral chains had stronger cytotoxicity. Additionally, we found that exposure to the ionic liquid 1-octyl-3-methylimidazolium bromide ([C(8)mim]Br) provoked cellular LDH release, increased mitochondrial depolarization, induced cellular transmogrification, nuclear shrinkage and DNA fragmentation, and promoted caspase-3 activity and ROS levels in PC12 cells. These results suggest that [C(8)mim]Br may induce PC12 cell apoptosis triggered by excessive ROS and mediated by mitochondrial depolarization and permeability transition. Our result may be helpful for illuminating the cytotoxicity mechanism of alkylmethylimidazolium-based ionic liquids and safely using them in the future.


Assuntos
Apoptose/efeitos dos fármacos , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Animais , Boratos/toxicidade , Caspase 3/metabolismo , Forma Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo
9.
Chemosphere ; 87(10): 1155-60, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22386458

RESUMO

In this work, Bi(4)Nb(x)Ta((1-x))O(8)I photocatalysts have been synthesized by solid state reaction method and characterized by powder X-ray diffraction, scanning electron microscope and UV-Vis near infrared diffuse reflectance spectroscopy. The photocatalytic activity of these photocatalysts was evaluated by the degradation of methyl orange (MO) in aqueous solutions under visible light, UV light and solar irradiation. The effects of catalyst dosage, initial pH and MO concentration on the removal efficiency were studied, and the photocatalytic reaction kinetics of MO degradation as well. The results indicated that Bi(4)Nb(x)Ta((1-x))O(8)I exhibited high photocatalytic activity for the removal of MO in aqueous solutions. For example, the removal efficiency of MO by Bi(4)Nb(0.1)Ta(0.9)O(8)I was as high as 92% within 12 h visible light irradiation under the optimal conditions: initial MO concentration of 5-10 mg L(-1), catalyst dosage of 6 g L(-1) and natural pH (6-8), the MO molecules could be completely degradated by Bi(4)Nb(0.1)Ta(0.9)O(8)I within 40 min under UV light irradiation, and the photodegradation efficiency reaches to 60% after 7 h solar irradiation. Furthermore, the photocatalytic degradation of Bisphenol A (BPA) was also investigated under visible light irradiation. It is found that 99% BPA could be mineralized by Bi(4)Nb(0.1)Ta(0.9)O(8)I after 16 h visible light irradiation. Through HPLC/MS, BOD, TOC, UV-Vis measurements, we determined possible degradation products of MO and BPA. The results indicated that MO was degradated into products which are easier to be biodegradable and innocuous treated, and BPA could be mineralized completely. Furthermore, the possibility for the photosensitization effect in the degradation process of MO under visible light irradiation has been excluded.


Assuntos
Compostos Azo/química , Corantes/química , Recuperação e Remediação Ambiental/métodos , Fenóis/química , Fotólise , Poluentes Químicos da Água/química , Compostos Azo/efeitos da radiação , Compostos Benzidrílicos , Bismuto/química , Catálise , Cromatografia Líquida de Alta Pressão , Corantes/efeitos da radiação , Iodo/química , Espectrometria de Massas , Nióbio/química , Oxigênio/química , Fenóis/efeitos da radiação , Tantálio/química , Fatores de Tempo , Poluentes Químicos da Água/efeitos da radiação
10.
Ecotoxicol Environ Saf ; 75(1): 180-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21944958

RESUMO

In the present study, the immunotoxicity of 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) on brocarded carp was evaluated by an acute exposure of 100-300mgL(-1) of [C(8)mim]Br for 7 days. The results showed 300mgL(-1) of [C(8)mim]Br exposure caused activity inhibition of specific and non-specific immune systems, mainly including IgM level, lysozyme activity, and complement C3 content, while 100mgL(-1) of [C(8)mim]Br activated fish immune system during the early periods of exposure (2-5 days). This result indicates that [C(8)mim]Br has immunotoxicity on brocarded carp. Additionally, histological observation revealed that 300mgL(-1) of [C(8)mim]Br-exposure led to remarkable damages to the hepatopancreas, kidney, and spleen of brocarded carp after 7 days of [C(8)mim]Br treatment, although not only change in kidney and spleen somatic indexes was found, but also no swelling or hemorrhage of carp viscera occurred.


Assuntos
Carpas/imunologia , Imidazóis/toxicidade , Sistema Imunitário/efeitos dos fármacos , Animais , Carpas/fisiologia , Complemento C3/metabolismo , Rim/efeitos dos fármacos , Rim/imunologia , Rim/metabolismo , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo
11.
Ecotoxicology ; 21(1): 253-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21912977

RESUMO

Acute toxicity of 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) to goldfish at different developmental stages and responses of the antioxidant system in adult goldfish were evaluated in the present study. The results indicate that post-embryonic developmental toxicity of [C(8)mim]Br on goldfish is developmental-stage dependent. The juvenile and larva goldfish are more sensitive to [C(8)mim]Br-toxicity than the adult fish. Histological observations in adult goldfish reveal that acute [C(8)mim]Br exposure damages the hepatopancreas, intestines, and kidneys, indicating that these are possible target organs of [C(8)mim]Br toxicity in goldfish. Subsequent biochemical assays in adult goldfish show that [C(8)mim]Br also induces changes in the activities of the superoxide dismutase, catalase, glutathione peroxidase, and glutathione content of fish hepatopancreas. These results suggest that [C(8)mim]Br exposure may induce oxidant stress and lipid peroxidation in hepatopancreas of adult goldfish. In addition, we also find that [C(8)mim]Br causes a remarkable increase in malondialdehyde (MDA) levels in the hepatopancreas of adult goldfish, and thus we think that the MDA level change can be a biomarker of [C(8)mim]Br toxicity in goldfish. The present study indicates that ionic liquids can be a threat to the survival, growth, and development of the fish population once they are accidentally leaked into aquatic ecosystems.


Assuntos
Antioxidantes/metabolismo , Carpa Dourada/crescimento & desenvolvimento , Carpa Dourada/metabolismo , Imidazóis/toxicidade , Animais , Catalase/efeitos dos fármacos , Catalase/metabolismo , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Intestinos/efeitos dos fármacos , Líquidos Iônicos/química , Líquidos Iônicos/toxicidade , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Malondialdeído/análise , Malondialdeído/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda
12.
Ecotoxicol Environ Saf ; 73(5): 1046-50, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20149456

RESUMO

To evaluate the toxicity of the ionic liquid 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) to Eisenia foetida, effects of [C(8)mim]Br on the growth, reproductive ability, and adenosine triphosphatase (ATPase) activity of earthworms were determined under laboratory conditions using artificial soil as substrate. The results showed that [C(8)mim]Br in high concentrations significantly inhibited the growth of the earthworms. These effects were enhanced with prolonged exposure to and increasing concentration of [C(8)mim]Br. E. foetida's reproductive ability was significantly inhibited after 42d of subchronic exposure to [C(8)mim]Br at a concentration >or=5 mg kg(-1) artificial soil (dry weight). During acute exposure, a high concentration of [C(8)mim]Br >or=40 mg kg(-1) artificial soil (dry weight) inhibited the activities of Na(+)-K(+)-ATPase and Mg(++)-ATPase after 3 and 7d of exposure. After 42d of subchronic exposure, the activity of both ATPases was inhibited in groups exposed to >or=5mg[C(8)mim]Brkg(-1) artificial soil (dry weight). These results indicate that treatment with the ionic liquid [C(8)mim]Br affects the growth, reproductive ability, and ATPase activity of earthworms E. foetida.


Assuntos
Adenosina Trifosfatases/metabolismo , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Relação Dose-Resposta a Droga , Oligoquetos/enzimologia , Oligoquetos/crescimento & desenvolvimento , Reprodução/efeitos dos fármacos
13.
Chemosphere ; 78(7): 853-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20044122

RESUMO

The activity changes of anti-oxidant enzymes and the levels of glutathione and malondialdehyde were determined when Eisenia foetida were exposed to different concentrations of 1-methyl-3-octylimidazolium bromide for 14d. The results showed catalase activity in all treatment groups was elevated significantly after 1d of exposure, and superoxide dismutase activity in higher-dosage groups (120 and 160mgkg(-1)) was increased at 3d post-exposure. On the 7thd, the activity of glutathione-S-transferase in the 20 and 40mgkg(-1) dosage groups was inhibited while increased in the 80 and 160mgkg(-1) groups compared with the control groups. During exposure, the level of intracellular glutathione in all treatment groups was much higher than that of the control groups. Changes in malondialdehyde indicate that [C(8)mim]Br may lead to cellular lipid peroxidation in earthworm. Our results suggest that exposure to [C(8)mim]Br induce the formation of reactive oxygen species in earthworms.


Assuntos
Antioxidantes/metabolismo , Imidazóis/toxicidade , Oligoquetos/enzimologia , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos , Malondialdeído/metabolismo , Oligoquetos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
14.
Environ Toxicol ; 25(3): 243-50, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19415752

RESUMO

The embryonic developmental toxicity of the ionic liquid (IL) 1-methyl-3-octylimidazolium bromide ([C(8)mim]Br) on the goldfish Carassius auratus was evaluated in this study. First, the 72 h 50% lethal concentrations (72 h-LC(50)) for [C(8)mim]Br in goldfish embryos at the stages of cleavage, early gastrula, closure of blastopore, and heart beating were determined by preliminary acute toxicity tests. After that, fish embryos in different developmental stages (cleavage, early gastrula, closure of blastopore, and heart beating) were exposed to 10.4, 20.8, 41.6, and 104 mg/L of [C(8)mim]Br until their hatching stage. The results of the acute toxicity tests showed that 72 h-LC(50) values at the early cleavage, early gastrula, closure of blastopore, and heart beating stages of development were 208.96, 187.1, 245.03, and 298.33 mg/L, respectively. In the subchronic tests, [C(8)mim]Br exposure prolonged the duration of embryo dechorionation and decreased the hatching rates of the treated embryos compared to control embryos. In addition, [C(8)mim]Br treatment also caused remarkable increases of embryonic malformation and mortality ratio in most treatment groups. Finally, we also found that the embryonic and developmental toxicity of [C(8)mim]Br on fish embryos was dose-response and developmental stage-specific. These results indicate that [C(8)mim]Br has toxic effects on the early embryonic development of goldfish, and the risk to aquatic ecosystem by ILs leaking into the water body must be evaluated in the future.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Carpa Dourada/embriologia , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Poluentes Químicos da Água/toxicidade , Análise de Variância , Animais , Dose Letal Mediana , Estrutura Molecular , Testes de Toxicidade
15.
Ecotoxicol Environ Saf ; 73(6): 1465-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19896712

RESUMO

In the present study, the acute toxicity of 1-Alkyl-3-methylimidazolium bromide ([Cnmim]Br) on the green algal Scenedesmus obliquus and Chlorella ellipsoidea was determined. The length of alkyl side chain of these imidazolium ionic liquids were C4, C6, C8, C10 and C12. The primary production of S. obliquus was also assessed after they were exposed to 0.01, 0.05, 0.10, 0.50 and 1.00 mg/L of [C10mim]Br for 96 h. The results showed that the acute toxicity of these ionic liquids was positively correlated with the alkyl chain length. Meanwhile, the concentration of the ionic liquid strongly influenced the primary production of algae. These results indicate that [Cnmim]Br with longer alkyl length have toxic effects on the green algae, and the risk to aquatic ecosystems by ionic liquid's leaking into the water body must be evaluated in the future.


Assuntos
Chlorella/efeitos dos fármacos , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Scenedesmus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Chlorella/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Imidazóis/química , Dose Letal Mediana , Scenedesmus/metabolismo , Especificidade da Espécie , Relação Estrutura-Atividade , Fatores de Tempo , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química
16.
Chemosphere ; 77(3): 313-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19682724

RESUMO

The earthworm Eisenia foetida was exposed to different concentrations of imidazolium ionic liquids with varying chain lengths according to the method of OECD [OECD, 1984. (The Current Organization of Economic and Cooperative Development Acute Earthworm Toxicity Test) Guidelines for the Testing of Chemicals, No. 207. Earthworm Acute Toxicity Tests]. The acute and subchronic toxic effects of [C(8)mim]Br on the activities of acetylcholinesterase (AChE) and cellulase in earthworms were determined under an artificial soil condition. Using filter paper contact tests, the 48 h-LC(50) values of [C(4)mim]Br, [C(6)mim]Br, [C(8)mim]Br, [C(10)mim]Br and [C(12)mim]Br on the earthworm were 73.33, 28.25, 2.69, 0.37 and 0.02 microg cm(-2), respectively. The 7 d-LC(50) of [C(8)mim]Br was 206.8 mg kg(-1) artificial soil (dry weight) and the 14 d-LC(50) was 159.4 mg kg(-1) artificial soil (dry weight), under the condition of artificial soil. After 1 d and 3 d of acute exposure, the activity of AChE was markedly inhibited when compared to the control, while it was increased at 7d. The cellulase activity was elevated significantly in the treatment groups of 20-160 mg kg(-1) after 3 and 7d of acute exposure. The activity of cellulase was also promoted under the subchronic exposure condition in the 10 and 20 mg kg(-1) groups. The experimental results suggest that [C(8)mim]Br may interfere with the nervous function of the earthworms and increase their cellulase activity. These results indicate that [C(8)mim]Br-exposure can affect the metabolized enzyme activity of earthworms at low concentrations and can even cause worm death at high doses, both of which have potential impacts on the soil environment.


Assuntos
Acetilcolinesterase/metabolismo , Celulase/metabolismo , Líquidos Iônicos/toxicidade , Oligoquetos/enzimologia , Poluentes do Solo/toxicidade , Acetilcolinesterase/efeitos dos fármacos , Animais , Celulase/efeitos dos fármacos , Imidazolinas/toxicidade , Oligoquetos/efeitos dos fármacos , Testes de Toxicidade Aguda
17.
Ecotoxicol Environ Saf ; 72(6): 1798-804, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19501400

RESUMO

This study examined the antioxidant responses of Daphnia magna following exposure to different concentrations of the ionic liquid (IL) 1-octyl-3-methylimidazolium bromide and the 50% LC(50) concentrations of methylimidazolium bromide ILs with different alkyl-chain lengths. Activities of antioxidant defense enzymes (superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase) and levels of the antioxidant glutathione and the lipid peroxidation by-product malondialdehyde were measured using traditional methods or commercial kits. The concentration and the alkyl-chain length of ILs were found to strongly influence the antioxidant system of D. magna following IL exposure, and exposure to higher IL concentrations and to ILs with longer alkyl chains generally increased the enzyme activities and biomarker levels examined. Therefore, the present study suggests that oxidative stress is involved in the mechanism of IL-induced toxicity in D. magna.


Assuntos
Antioxidantes/metabolismo , Daphnia/efeitos dos fármacos , Daphnia/enzimologia , Hidrocarbonetos Bromados/toxicidade , Líquidos Iônicos/toxicidade , Animais , Boratos/toxicidade , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Hidrocarbonetos Bromados/química , Imidazóis/toxicidade , Líquidos Iônicos/química , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo , Testes de Toxicidade Aguda
18.
Ecotoxicol Environ Saf ; 72(2): 552-6, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18082266

RESUMO

Toxic effects of 1-methyl-3-octylimidazolium bromide ([C8mim]Br) on the early embryonic development of the frog Rana nigromaculata were evaluated. Frog embryos in different developmental stages (early cleavage, early gastrula, or neural plate) were exposed to 0, 45, 63, or 88.2 mg/L of the ionic liquid [C8mim]Br for 96 h. The 96-h median lethal concentration values at the early cleavage, early gastrula, and neural plate stages of development were 85.1, 43.4, and 42.4 mg/L, respectively. In embryos exposed to [C8mim]Br, the duration of embryo dechorionation was prolonged in the early cleavage and neural plate, but not the early gastrula, stages of development compared with control embryos. Embryos in the neural plate developmental stage were found to have the highest mortality rate following [C8mim]Br exposure. These results suggest that [C8mim]Br has toxic effects on the early embryonic development of the frog.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Gástrula/efeitos dos fármacos , Hidrocarbonetos Bromados/toxicidade , Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Ranidae , Animais , Desenvolvimento Embrionário/fisiologia , Feminino , Gástrula/crescimento & desenvolvimento , Gástrula/metabolismo , Ranidae/embriologia , Ranidae/crescimento & desenvolvimento , Ranidae/metabolismo , Fatores de Tempo
19.
Environ Toxicol ; 24(3): 296-303, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18767141

RESUMO

Although many studies describe ionic liquids (ILs) as potentially greener solvents, few studies address their relationship with the environment. Recent researches suggest that some ILs have toxicity. 1-Butyl-3-methylimidazolium tetrafluoroborate ([C4mim][BF4]) was reported to have the lowest toxicity among ILs. In this work, we studied the toxicity of this IL on wheat seedlings. It was shown that wheat germination was reduced to 38.0% in the presence of 4.4 mmol/L [C4mim][BF4] compared with 100% germination for the control. Similarly, the root and shoot length of wheat seedlings decreased with increasing concentrations of [C4mim][BF4]. The activity of amylase increased in shoots and roots, but it decreased significantly in germinating seeds when the [C4mim][BF4] concentration exceeded 1.8 mmol/L. Peroxidase (POD) activity and soluble protein content in shoots treated with [C4mim][BF4] changed similarly, but chlorophyll content tended to decrease with increasing concentration of [C4mim][BF4], except for at 1.8 mmol/L. Thus, [C4mim][BF4] at the concentration of 0.9 mmol/L or more was toxic to wheat seedlings. Some remedial measures are suggested to deal with IL pollution in the environment.


Assuntos
Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Plântula/efeitos dos fármacos , Triticum/efeitos dos fármacos , Amilases/metabolismo , Clorofila/análise , Peroxidase/metabolismo , Proteínas de Plantas/análise , Raízes de Plantas/química , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Plântula/enzimologia , Plântula/crescimento & desenvolvimento , Sementes/química , Sementes/efeitos dos fármacos , Sementes/enzimologia , Testes de Toxicidade , Triticum/enzimologia , Triticum/crescimento & desenvolvimento
20.
Ecotoxicol Environ Saf ; 71(3): 903-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18423588

RESUMO

The effects of acute exposure of intraperitoneal injection of aqueous 1-octyl-3-methylimidazolium bromide on the antioxidant enzymes and lipid peroxidation of the treated mouse liver were investigated in the present paper. Thirty mice were treated with 17.9 (0.5 median lethal dose, LD(50)) and 35.7 mg/kg (1 LD(50)) of the ionic liquid or saline solution by intraperitoneal injection for 10h. Significant increase in hepatosomatic index and decrease in liver protein content were found in 1 LD(50) group. No statistically significant change was observed in the activity of superoxide dismutase in both treated groups compared to the control group. In the case of catalase activity, the decrease was recorded only at dose of 1 LD(50). As for the activity of glutathione peroxidase, increase in 0.5 LD(50) group while significant decrease at dose of 1 LD(50) was noted. There was an increase in the activity of glutathione-S-transferase in these two treated groups in comparison to the control. However, no effect on the level of lipid peroxidation was found in the treated groups. These results showed that the acute exposure of aqueous ionic liquid could cause damage to mouse, leading to antioxidant responses in livers of the treated mice.


Assuntos
Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Fígado/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Catalase/farmacologia , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Dose Letal Mediana , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Camundongos , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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