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1.
Biomed Pharmacother ; 145: 112438, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34861632

RESUMO

The aim of this work was to investigate the in vitro cytotoxic effect of previously developed nanocapsules, nanoemulsion, and microemulsion based on bullfrog oil (BFO) against human melanoma cells (A2058). The nanosystems were produced as described in previous studies and characterized according to droplet/particle distribution and zeta potential. The biocompatibility was evaluated by the determination of the hemolytic potential against human erythrocytes. The cytotoxicity assessment was based on MTT and cell death assays, determination of Reactive Oxygen Species (ROS) levels, and cell uptake. The nanosystems were successfully reproduced and showed hemolytic potential smaller than 10% at all oil concentrations (50 and 100 µg.mL-1) (p < 0.05). The MTT assay revealed that the nanosystems decreased the mitochondrial activity up to 92 ± 2% (p < 0.05). The study showed that the free BFO induced cell apoptosis, while all the nanostructured systems caused cell death by necrosis associated with a ROS overproduction. This can be related to the increased ability of the nanostructured systems to deliver the BFO across all cellular compartments (membrane, cytoplasm, and nucleus). Finally, these results elucidate the in vitro BFO nanosystems cytotoxic effect against human melanoma cells (A2058), revealing the emulsified ones as the most cytotoxic systems. Overall, the findings suggest that the safety and antineoplastic activity of these systems can be further investigated by in vivo studies.


Assuntos
Antineoplásicos/farmacologia , Melanoma/tratamento farmacológico , Nanoestruturas , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Emulsões , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Melanoma/patologia , Mitocôndrias/metabolismo , Nanocápsulas , Óleos/isolamento & purificação , Óleos/farmacologia , Óleos/toxicidade , Tamanho da Partícula , Rana catesbeiana/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/patologia
2.
Asian Pac J Cancer Prev ; 22(11): 3591-3599, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837917

RESUMO

BACKGROUND: Cooking oil fumes (COFs) with smoking habits is a substantial risk that aggravates genetic modifications. The current study was to estimate the biological markers of genetic toxicity counting Micronucleus changes (MN), Chromosome Aberrations (CA) and DNA modifications among COFs exposures and control subjects inherent from South India. MATERIALS AND METHODS: Present analysis comprised 212 COFs with tobacco users and equivalent number of control subjects. RESULTS: High frequency of CA (Chromatid type: and chromosome type) were identified in group II experimental subjects also high amount of MN and DNA damage frequency were significantly (p < 0.05) in both subjects (experimental smokers and non-smokers). Present analysis was observed absence of consciousness among the COFs exposures about the destructive level of health effects of tobacco habits in working environment. CONCLUSION: COFs exposed workers with tobacco induce the significant alteration in chromosomal level. Furthermore, a high level of rate of genetic diseases (spontaneous abortion) were identified in the experimental subjects. This finding will be helpful for preventive measures of COFs exposed workers and supportive for further molecular analysis.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , Culinária , Dano ao DNA/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Óleos/toxicidade , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Estudos de Casos e Controles , Análise Citogenética , Feminino , Humanos , Índia , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Uso de Tabaco/genética
3.
Ecotoxicol Environ Saf ; 221: 112463, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198188

RESUMO

BACKGROUND: Cooking oil fumes (COF) is one of the primary sources of indoor air pollution in China, which is associated with respiratory diseases such as acute lung injury and lung cancer. However, evidence of COF toxic effect was few. OBJECTIVES: The research was aimed to investigate the toxic effect and the underlying mechanisms induced by COF. METHODS: The female Wistar rats were randomly divided into several groups, including control group, COF exposure group and VE protection group, and instilled intratracheally with different COF suspensions (0.2, 2, 20 mg/kg) or saline once every 3 days for 30 days. After 24 h of final exposure, all rat were anesthetic euthanasia to draw materials. The alveolar lavage fluid (BALF) was for inflammatory cell count. The lung homogenate was to determine the biochemical indexes such as oxidative stress, apoptosis factors, carcinogenic toxicity and endoplasmic reticulum (ER) stress. The left lung was made for immunohistochemical and histopathological analysis. RESULTS: The results showed that the levels of oxidative stress (ROS), apoptosis factors (NF-κB), carcinogenic toxicity (P53 and 8-OhdG), ER stress (IRE-1α and Caspase-12) in 2 mg/kg and 20 mg/kg COF exposure groups were significantly increased compared with the saline groups. The above pathological changes were improved after vitamin E (VE) supplementation. In addition, the immunohistochemical and histopathological analysis found the same trend. CONCLUSION: The COF had health risk of heredity and potential carcinogenicity. Besides, COFs can not only induce oxidative stress, but also induce ER stress in lung and airway epithelial cells of female rats through the unfolded protein reaction (UPR) pathway. It revealed that the oxidative stress and ER stress interacted in aggravating lung injury. VE could effectively alleviate the lung injury causing by COF exposure.


Assuntos
Poluentes Atmosféricos/toxicidade , Culinária , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Óleos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Feminino , Pulmão/efeitos dos fármacos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Vitamina E/uso terapêutico
4.
Aquat Toxicol ; 228: 105651, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33049420

RESUMO

Many early stages of estuarine species congregate at the surface or in the upper mixing layer making them prone to UV light exposure and oil sheens. Laboratory testing was used to assess UV-oil sheen interactions with grass shrimp (Palaemon pugio). Newly hatched grass shrimp larvae were exposed to a 1-µm thick oil sheen for 24 h with or without an 8-h pulse of UV light. Grass shrimp were then transferred to clean seawater and non-UV conditions to measure development, growth, and reproductive fitness. Minimal toxicity was observed after the initial exposure but larval development was significantly delayed in shrimp exposed to the UV enhanced sheen. After reaching sexual maturity, shrimp were paired to evaluate effects on reproduction. Shrimp initially exposed to the UV enhanced sheen as larvae had a significant reduction in fecundity compared to controls. This demonstrates the importance of examining interactions between UV light and oil since negative effects to aquatic organisms may be underestimated if based on standard laboratory fluorescent lighting. Acute exposures of early life stages to thin oil sheens and UV light may lead to long-term impacts to individuals and ultimately to grass shrimp populations.


Assuntos
Exposição Ambiental , Óleos/toxicidade , Palaemonidae/crescimento & desenvolvimento , Palaemonidae/efeitos da radiação , Animais , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/efeitos da radiação , Masculino , Palaemonidae/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/análise , Reprodução/efeitos dos fármacos , Reprodução/efeitos da radiação , Água do Mar , Raios Ultravioleta , Poluentes Químicos da Água/toxicidade
5.
Cutan Ocul Toxicol ; 39(3): 193-199, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32406268

RESUMO

INTRODUCTION: The American cockroach (Periplaneta americana) is used in traditional Chinese medicine. Periplaneta americana (P. americana) is rich in oil that has shown potential antioxidant and antibacterial activities in vitro. OBJECTIVE: To evaluate the safety of oil extracted from P. americana by conducting acute dermal toxicity, irritation, and sensitization tests. MATERIALS AND METHODS: In an acute dermal toxicity study, adult Sprague-Dawley rats were exposed to P. americana oil (2000 mg/kg body weight) for 24 h. Clinical observations were conducted to evaluate the toxicity, behaviour, and health of the animals every day after dermal exposure for 14 days. For the dermal irritation test, the oil was applied to rabbits in single and multiple doses. Multi-dose treatment was administered once per day for 14 days. Each rabbit served as its own left- and right-side control and the rabbits' irritation reactions in local intact and damaged skin were recorded and scored. The skin sensitization study of guinea pigs with the oil was conducted for a period of 28 days. RESULTS: The acute dermal median lethal dose (LD50) of P. americana oil was > 2000 mg/kg body weight in adult rats. There was no significant difference in mean irritation scores between the negative control and oil groups. The oil caused very little or no irritation in the intact and damaged skin rabbits treated with either single or multiple doses and it was non-sensitizing to the skin of guinea pigs. CONCLUSIONS: These results suggest that P. americana oil does not produce any significant acute toxic effects and is safe for use in animal models with almost no dermal irritation or sensitization. Therefore, it presents a low risk of provoking skin reactions in humans.


Assuntos
Óleos/toxicidade , Periplaneta , Pele/efeitos dos fármacos , Animais , Feminino , Cobaias , Dose Letal Mediana , Masculino , Coelhos , Ratos Sprague-Dawley , Testes de Toxicidade
6.
J Vis Exp ; (153)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31789319

RESUMO

Elevated intraocular pressure (IOP) is a well-documented risk factor for glaucoma. Here we describe a novel, effective method for consistently inducing stable IOP elevation in mice that mimics the post-operative complication of using silicone oil (SO) as a tamponade agent in human vitreoretinal surgery. In this protocol, SO is injected into the anterior chamber of the mouse eye to block the pupil and prevent inflow of aqueous humor. The posterior chamber accumulates aqueous humor and this in turn increases the IOP of the posterior segment. A single SO injection produces reliable, sufficient, and stable IOP elevation, which induces significant glaucomatous neurodegeneration. This model is a true replicate of secondary glaucoma in the eye clinic. To further mimic the clinical setting, SO can be removed from the anterior chamber to reopen the drainage pathway and allow inflow of aqueous humor, which is drained through the trabecular meshwork (TM) at the angle of the anterior chamber. Because IOP quickly returns to normal, the model can be used to test the effect of lowering IOP on glaucomatous retinal ganglion cells. This method is straightforward, does not require special equipment or repeat procedures, closely simulates clinical situations, and may be applicable to diverse animal species. However, minor modifications may be required.


Assuntos
Modelos Animais de Doenças , Hipertensão Ocular/induzido quimicamente , Hipertensão Ocular/patologia , Silício/toxicidade , Animais , Humor Aquoso/efeitos dos fármacos , Humor Aquoso/fisiologia , Injeções Intraoculares , Pressão Intraocular/efeitos dos fármacos , Pressão Intraocular/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óleos/administração & dosagem , Óleos/toxicidade , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/fisiologia , Silício/administração & dosagem
7.
Biomark Med ; 13(13): 1119-1128, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31512508

RESUMO

Aim: We studied the association between two single-nucleotide polymorphisms (SNPs: rs4787050 and rs8045980) in RBFOX1 and lung cancer risk, and explored the interaction between the two SNPs and exposure to cooking oil fume on lung cancer risk in northeast Chinese female nonsmokers. Methods: Northeast Chinese female nonsmokers were enrolled into the study (people with lung cancer, 647; people without lung cancer, 675). All statistical analyses were performed using SPSS software. Results: The SNPs rs4787050 and rs8045980 showed a significant association with susceptibility to lung cancer. Moreover, cooking oil fume exposure was found to increase the risk of lung cancer. However, no gene-environment interactions were discovered. Conclusion: The present study revealed that rs4787050 and rs8045980 in RBFOX1 may be meaningful as a novel biomarker for lung cancer susceptibility.


Assuntos
Povo Asiático/genética , Neoplasias Pulmonares/diagnóstico , Fatores de Processamento de RNA/genética , Adulto , Idoso , Estudos de Casos e Controles , China , Exposição Ambiental , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Desequilíbrio de Ligação , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Pessoa de Meia-Idade , não Fumantes , Óleos/química , Óleos/toxicidade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
8.
Environ Toxicol Chem ; 37(9): 2372-2379, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29856086

RESUMO

The toxicity of some polycyclic aromatic hydrocarbons (PAHs) increases with ultraviolet (UV) radiation. The intensity of UV radiation varies within aquatic ecosystems, potentially providing reprieves during which tissue repair may occur. Transient/short-term PAH exposure prior to UV exposure may initiate metabolism/clearance, potentially affecting outcomes. Larval Sciaenops ocellatus were exposed to oil and UV radiation, using either variable photoperiods or pre-UV oil exposure durations. Shorter PAH exposures exhibited greater toxicity, as did exposure to shorter photoperiods. Environ Toxicol Chem 2018;37:2372-2379. © 2018 SETAC.


Assuntos
Óleos/toxicidade , Perciformes/fisiologia , Raios Ultravioleta , Animais , Larva/efeitos dos fármacos , Larva/efeitos da radiação , Hidrocarbonetos Policíclicos Aromáticos/análise , Análise de Sobrevida , Poluentes Químicos da Água/toxicidade
9.
Int J Biol Macromol ; 112: 294-305, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29366887

RESUMO

Herein, synthesized and compared the three different kinds of hybrid bio-polymeric composites viz., lanthanum embedded chitosan/gelatin (La@CS-GEL), zirconium embedded chitosan/gelatin (Zr@CS-GEL) and cerium embedded chitosan/gelatin (Ce@CS-GEL) in terms of their oil uptake efficiency. The adsorption efficiency was studied under various optimized parameters like contact time, pH, dose, initial oil concentration and temperature. The oil adsorption capacity was found to be 91, 82 and 45% for La@CS-GEL, Zr@CS-GEL and Ce@CS-GEL composites respectively. The metals were used as a bridging material to connect both CS and GEL using the hydrophilic groups to enhance the oil recovery by hydrophobic interaction. Also, the introduction of metal ions on the surface of biopolymers would modify the oil/water properties which in turn, decrease the interfacial tension between oil and water phases. The mechanism of oil uptake was explained using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM), energy dispersive X-ray (EDAX) and heat of combustion. The experimental data confirmed Langmuir isotherm as the best fit for oil adsorption process. Thermodynamic parameters such as standard free energy (ΔG°), standard enthalpy (ΔH°) and standard entropy (ΔS°) indicated that the oil adsorption was spontaneous and endothermic. The oil adsorption mechanism was established based on isotherm and thermodynamic models.


Assuntos
Adsorção , Biopolímeros/química , Óleos/isolamento & purificação , Poluição por Petróleo/prevenção & controle , Quitosana/química , Humanos , Íons/química , Lantânio/química , Óleos/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Termogravimetria , Difração de Raios X , Zircônio/química
10.
Food Chem Toxicol ; 103: 270-278, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28284730

RESUMO

The purpose of this study was to investigate the reproductive and developmental toxicity of dietary exposure to DHA-rich oil from Schizochytrium sp. and ARA-rich oil from Mortierella alpina. In a developmental toxicity study, pregnant Wistar rats were untreated (control) or administered corn oil (vehicle control), 1000, 2500, or 5000 mg/kg bw/day of DHA-rich oil or ARA-rich oil via gavage from gestation days 6 through 20. In the reproductive toxicity study, male and female Wistar rats were administered vehicle control (corn oil), or 1000, 2500, or 5000 mg/kg bw/day of DHA- or ARA-rich oil via gavage throughout the mating period, pregnancy, and the nursing and lactation period. Differences in the number of fetuses, fetal skeletal malformations, and external and visceral anomalies in the developmental study and mortality, clinical signs, fertility indices, physical observations, gross necropsy findings, and gestation period length in the reproductive toxicity study were not dose-related or significantly different from control groups, and were not considered to be treatment related. The no observed adverse effect level (NOAEL) for maternal toxicity and embryo/fetal development and for paternal or maternal treatment-related reproductive toxicity for the DHA-rich oil and ARA-rich oil administered by gavage, was 5000 mg/kg bw/day.


Assuntos
Ácido Araquidônico/toxicidade , Ácidos Docosa-Hexaenoicos/toxicidade , Óleos/toxicidade , Reprodução/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Histerectomia , Masculino , Mortierella/química , Óleos/química , Gravidez , Ratos Wistar , Estramenópilas/química , Taxa de Sobrevida
11.
Toxicol Ind Health ; 33(5): 385-405, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27343050

RESUMO

Metalworking fluids (MWFs) are complex formulations designed for effective lubricating, cooling, and cleaning tools and parts during machining operations. Adverse health effects such as respiratory symptoms, dermatitis, and cancer have been reported in workers exposed to MWFs. Several constituents of MWFs have been implicated in toxicity and have been removed from the formulations over the years. However, animal studies with newer MWFs demonstrate that they continue to pose a health risk. This investigation examines the hypothesis that unrecognized health hazards exist in currently marketed MWF formulations that are presumed to be safe based on hazard assessments of individual ingredients. In vivo 13-week inhalation studies were designed to characterize and compare the potential toxicity of four MWFs: Trim VX, Cimstar 3800, Trim SC210, and Syntilo 1023. Male and female Wistar Han rats or Fischer 344N/Tac rats and B6C3F1/N mice were exposed to MWFs via whole-body inhalation at concentrations of 0, 25, 50, 100, 200, or 400 mg/m3 for 13 weeks, after which, survival, body and organ weights, hematology and clinical chemistry, histopathology, and genotoxicity were assessed following exposure. Although high concentrations were used, survival was not affected and toxicity was primarily within the respiratory tract of male and female rats and mice. Minor variances in toxicity were attributed to differences among species as well as in the chemical components of each MWF. Pulmonary fibrosis was present only in rats and mice exposed to Trim VX. These data confirm that newer MWFs have the potential to cause respiratory toxicity in workers who are repeatedly exposed via inhalation.


Assuntos
Exposição por Inalação/análise , Lubrificantes/toxicidade , Pulmão , Metalurgia , Fibrose Pulmonar , Animais , Feminino , Laringe/química , Laringe/efeitos dos fármacos , Pulmão/química , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Nariz/química , Nariz/efeitos dos fármacos , Óleos/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Ratos , Tensoativos/toxicidade , Testes de Toxicidade
12.
Molecules ; 21(5)2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27144557

RESUMO

Bullfrog oil is a natural product extracted from the Rana catesbeiana Shaw adipose tissue and used in folk medicine for the treatment of several diseases. The aim of this study was to evaluate the extraction process of bullfrog oil, to develop a suitable topical nanoemulsion and to evaluate its efficacy against melanoma cells. The oil samples were obtained by hot and organic solvent extraction processes and were characterized by titration techniques and gas chromatography mass spectrometry (GC-MS). The required hydrophile-lipophile balance and the pseudo-ternary phase diagram (PTPD) were assessed to determine the emulsification ability of the bullfrog oil. The anti-tumoral activity of the samples was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for normal fibroblast (3T3) and melanoma (B16F10) cell lines. Both extraction methods produced yielded around 60% and the oil was mainly composed of unsaturated compounds (around 60%). The bullfrog oil nanoemulsion obtained from PTPD presented a droplet size of about 390 nm and polydispersity = 0.05 and a zeta potential of about -25 mV. Both the bullfrog oil itself and its topical nanoemulsion did not show cytotoxicity in 3T3 linage. However, these systems showed growth inhibition in B16F10 cells. Finally, the bullfrog oil presented itself as a candidate for the development of pharmaceutical products free from cytotoxicity and effective for antineoplastic therapy.


Assuntos
Antineoplásicos/isolamento & purificação , Produtos Biológicos/uso terapêutico , Melanoma Experimental/tratamento farmacológico , Óleos/uso terapêutico , Rana catesbeiana , Células 3T3 , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Pesquisa Biomédica/tendências , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Emulsões , Células HeLa , Humanos , Camundongos , Óleos/química , Óleos/isolamento & purificação , Óleos/toxicidade
13.
J Health Psychol ; 21(9): 1939-48, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-25645936

RESUMO

Synthol is an injectable oil used by bodybuilders to make muscles appear bigger. Widely available on the Internet, it is reported to carry a wide range of health risks and side effects such as localised skin problems, nerve damage and oil-filled cysts, as well as muscle damage and the development of scar tissue. Given the tension between health risk and quick muscle enlargement, how lay users explain and justify their synthol intake becomes an important question. Drawing on discourse analysis, we focus on how lay expertise is worked up by users in the absence of available specialist knowledge by invoking medical and pharmaceutical discourses as legitimation, providing novices with support, gaining trust through positive personal narratives and thus gaining credibility as experts. Results have clear implications for health promotion interventions with bodybuilders.


Assuntos
Atitude Frente a Saúde , Dopagem Esportivo/psicologia , Internet , Músculo Esquelético/efeitos dos fármacos , Óleos/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto , Humanos , Injeções Intramusculares , Masculino , Óleos/toxicidade , Substâncias para Melhoria do Desempenho/toxicidade , Risco
14.
IET Nanobiotechnol ; 9(4): 172-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26224345

RESUMO

Microemulsion-based animal oils, alone or associated with polymers have been extensively used in pharmacy, medicine and cosmetics, since the major lipid constituents of the oils show several biological activities. Despite showing antimicrobial activity, there are no reports in the literature regarding the effects of bullfrog oil on cytotoxic activity against tumor cells. The aim of the present study was to synthesize, characterise and evaluate the in vitro effects on melanoma cell line (B16F10) of bullfrog oil microemulsions associated or not with chitosan, surfactant and bullfrog oil (CSBO) and surfactant and bullfrog oil (SBO), respectively. The microemulsions were developed and their physical-chemical characteristics were evaluated by light microscopy, dynamic light scattering, atomic force microscopy and zeta potential. The microemulsions showed regular spherical shapes, high polydispersity and excellent (+82.2 ± 1.0 mV) to low (-16.0 ± 0.5 mV), colloidal stability. The systems significantly decreased the in vitro cell viability of melanoma skin cancer by up to 90.2% (CSBO) and 91.8% (SBO); while free bullfrog oil showed no effects. The results obtained from microemulsions of bullfrog oil indicate the potential of the microemulsions developed, alone or in combination with other chemotherapeutic agents, for future use in biomedical approaches aiming towards cancer therapy.


Assuntos
Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Emulsões/toxicidade , Óleos/toxicidade , Rana catesbeiana/metabolismo , Animais , Antineoplásicos/química , Produtos Biológicos , Linhagem Celular Tumoral , Emulsões/química , Melanoma , Óleos/química , Tamanho da Partícula
15.
Int J Toxicol ; 33(6): 459-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25305242

RESUMO

Almega PL is an eicosapentaenoic acid-rich ω-3 oil that is isolated from Nannochloropsis oculata algae and developed as a dietary supplement. The safety of the algal oil was evaluated in 14- and 90-day studies in Sprague-Dawley rats by oral gavage at dose levels of 0, 250, 500, and 2500 mg/kg/d and 0, 200, 400, and 2000 mg/kg/d, respectively. No mortalities occurred and no signs of toxicity were observed during the studies. No treatment-related effects were seen for body weight, food consumption, ophthalmology, neurological effects, urinalysis, clinical pathology, gross pathology, organ weights, or histopathology. Although statistically significant effects were noted for some end points, none were considered to be of toxicological significance. The no observed adverse effect level for Almega PL was 2000 mg/kg/d. Additionally, Almega PL was not mutagenic in Salmonella typhimurium or Escherichia coli, did not induce chromosome aberrations in Chinese hamster ovary cells, and did not induce genotoxic effects in vivo in rat bone marrow erythrocytes.


Assuntos
Ácido Eicosapentaenoico/toxicidade , Microalgas , Óleos/toxicidade , Estramenópilas , Animais , Células CHO , Aberrações Cromossômicas , Cricetulus , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Feminino , Masculino , Dose Máxima Tolerável , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Testes de Toxicidade Subaguda , Testes de Toxicidade Subcrônica
16.
ACS Appl Mater Interfaces ; 6(22): 19933-42, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25347002

RESUMO

A highly hydrophobic and oleophilic chitin sponge was synthesized, for the first time, via a freeze-dried method and then by using a thermal chemical vapor deposition of methyltrichlorosilane (MTCS) at different relative humidity. Fourier-transform infrared, energy-dispersive X-ray spectra, and scanning electron microscopy confirmed that the silanization occurred on the pore wall surface of the chitin sponge. The MTCS-coated chitin sponge had interconnected open-cell structures with the average pore size from 20 to 50 µm, and the MTCS nanofilaments immobilized on the chitin matrix, leading to the high hydrophobicity, as a result of the existence of a solid/air composite rough surface. Cyclic compression test indicated that the hydrophobic chitin sponges exhibited excellent elasticity and high mechanical durability. The sponges could efficiently collect organics both on the surface and bottom from the water with the highest 58 times of their own weight absorption capacities through the combination of the particular wettability and great porosity. Furthermore, the biodegradation kinetics of the chitin sponge forecasted that the chitin could be completely biodegraded within 32 days by the microorganisms in the soil. This work provided a new pathway to prepare the chitin-based materials for highly effective removal of oil from water, showing potential application in the pollutant remediation field.


Assuntos
Biodegradação Ambiental , Quitina/síntese química , Silanos/química , Purificação da Água , Quitina/química , Liofilização , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Óleos/toxicidade , Água/química , Poluição Química da Água , Molhabilidade
17.
Arch Environ Contam Toxicol ; 65(4): 790-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24121718

RESUMO

Toxicity tests evaluated chronic and sublethal effects of fog oil (FO) on a freshwater endangered fish. FO is released during military training as an obscurant smoke that can drift into aquatic habitats. Fountain darters, Etheostoma fonticola, of four distinct life stages were exposed under laboratory conditions to three forms of FO. FO was vaporized into smoke and allowed to settle onto water, violently agitated with water, and dosed onto water followed by photo-oxidization by ultraviolet irradiation. Single smoke exposures of spawning adult fish did not affect egg production, egg viability, or adult fish survival in 21-day tests. Multiple daily smoke exposures induced mortality after 5 days for larvae fish. Larvae and juvenile fish were more sensitive than eggs in 96-h lethal concentration (LC50) tests with FO­water mixtures and photo-oxidized FO. Water-soluble FO components photo-modified by ultraviolet radiation were the most toxic, thus indicating the value of examining weathering and aging of chemicals for the best determination of environmental impact.


Assuntos
Óleos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Espécies em Perigo de Extinção , Militares/educação , Percas , Medição de Risco , Tempo (Meteorologia)
18.
Chemosphere ; 92(7): 821-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23683868

RESUMO

In this study, possible toxicity of increasing doses of PCB-118 and transformer oil (TO) on anaerobic sludge digestion was investigated. For this purpose, five different sets of reactors were prepared in which four different PCB-118 concentration (1, 10, 20, and 30mgL(-1)) and three different TO concentration (0.38, 0.76, and 1.52gL(-1)) were applied. Throughout the study, biogas production and composition, pH, TS, VS, and COD as well as PCB concentration were monitored. Toxicity was investigated by anaerobic toxicity assay (ATA) evaluating the reduction in methane production. A notable inhibition was observed mostly in 30mgL(-1) PCB reactors. A negative influence of PCB-118 and TO was observed on COD and solids removal. A maximum of 26.5% PCB-118 removal was attained.


Assuntos
Óleos/toxicidade , Bifenilos Policlorados/toxicidade , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biocombustíveis , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos , Concentração de Íons de Hidrogênio , Metano/biossíntese , Bifenilos Policlorados/análise , Bifenilos Policlorados/isolamento & purificação , Eliminação de Resíduos Líquidos/instrumentação
19.
Bioresour Technol ; 133: 500-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23455221

RESUMO

This work was to utilize acetic acid contained in bio-oil for growth and lipid production of the microalga Chlamydomonas reinhardtii. The acetic acid-rich bio-oil fraction derived from fast pyrolysis of softwood contained 26% (w/w) acetic acid, formic acid, methanol, furfural, acetol, and phenolics as identified compounds, and 13% (w/w) unidentified compounds. Among those identified compounds, phenolics were most inhibitory to algal growth, followed by furfural and acetol. To enhance the fermentability of the bio-oil fraction, activated carbon was used to reduce the toxicity of the bio-oil, while metabolic evolution was used to enhance the toxicity tolerance of the microalgae. Combining activated carbon treatment and using evolved algal strain resulted in significant algal growth improvement. The results collectively showed that fast pyrolysis-fermentation process was a viable approach for converting biomass into fuels and chemicals.


Assuntos
Ácido Acético/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Biocombustíveis/toxicidade , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Óleos/farmacologia , Temperatura , Carvão Vegetal/farmacologia , Fracionamento Químico , Chlamydomonas reinhardtii/efeitos dos fármacos , Chlamydomonas reinhardtii/metabolismo , Ácidos Graxos/metabolismo , Fermentação/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Óleos/toxicidade
20.
Toxicol In Vitro ; 27(3): 1089-101, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23376439

RESUMO

Medical literature regularly reports on accidental poisoning in children after aspiration of combustibles such as lamp oils which usually contain hydrocarbons or rape methyl esters (RMEs). We aimed to analyze the toxic potential of alkanes and different combustible classes in vitro with regard to biologic responses and mechanisms mediating toxicity. Two different in vitro models were used, i.e. (i) a captive bubble surfactometer (CBS) to assess direct influence of combustibles on biophysical properties of surfactant film and (ii) cell cultures (BEAS-2B and R3/1 cells, primary macrophages, re-differentiated epithelia) closely mimicking the inner lung surface. Biological endpoints included cell viability, cytotoxicity and inflammatory mediator release. CBS measurements demonstrate that combustibles affect film dynamics, i.e. the surface tension/area characteristics during compression and expansion, in a dose and molecular chain length dependent manner. Cell culture results confirm the dose dependent toxicity. Generally, cytotoxicity and cytokine release are higher in short-chained alkanes and hydrocarbon-based combustibles than in long-chained substances, e.g. highest inducible cytotoxicity in BEAS-2B was for hexane 84.6%, decane 74% and hexadecane 30.8%. Effects of RME-based combustibles differed between the cell models. Our results confirm data from animal experiments and give new insights into the mechanisms underlying the adverse health effects observed.


Assuntos
Hidrocarbonetos/toxicidade , Óleos/toxicidade , Animais , Biocombustíveis/toxicidade , Brônquios/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Ésteres/toxicidade , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Ratos , Aspiração Respiratória , Suínos , Testes de Toxicidade/métodos
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