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1.
Toxicol Ind Health ; 39(10): 603-612, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37518894

RESUMO

Chloroform is a widely used industrial chemical that can also pollute the environment. The aims of this study were to examine the potential cytotoxicity and genotoxicity of chloroform on plant cells, using the Vicia faba bioassay. Chloroform was evaluated at concentrations of 0.1, 0.5, 1, 2, and 5 mg·L-1. The following parameters were analyzed: the mitotic index (MI), micronucleus (MN) frequency, chromosomal aberration (CA) frequency, and malondialdehyde (MDA) content. The results showed that exposure to increasing concentrations of chloroform caused a decrease in MI and an increase in the frequency of MN in Vicia faba root tip cells, relative to their controls. Moreover, various types of CA, including C-mitosis, fragments, bridges, laggard chromosomes, and multipolar mitosis, were observed in the treated cells. The frequency of MN was positively correlated with the frequency of CA in exposure to 0.1-1 mg·L-1 chloroform. Furthermore, chloroform exposure induced membrane lipid peroxidation damage in the Vicia faba radicle, and a linear correlation was observed between the MDA content and the frequency of MN or CA. These findings indicated that chloroform exposure can result in oxidative stress, cytotoxicity, and genotoxicity in plant cells.


Assuntos
Vicia faba , Clorofórmio/toxicidade , Testes para Micronúcleos , Raízes de Plantas/genética , Meristema , Aberrações Cromossômicas/induzido quimicamente
2.
Chem Biodivers ; 20(3): e202200755, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36722706

RESUMO

Fraxinus xanthoxyloides is a perennial shrub belonging to family Oleaceae, traditionally used for malaria, jaundice, pneumonia, inflammation, and rheumatism. Our study is aimed to assess the total phenolics (TPC), flavonoids (TFC), terpenoids contents (TTC) and antioxidant profiling of F. xanthoxyloides methanol bark extract (FXBM) and its fractions, hexane, chloroform, ethyl acetate and aqueous, along with high-performance liquid chromatography with diode-array detection (HPLC-DAD). Further, the antioxidant and pulmonary protective potential was explored against carbon tetrachloride (CCl4 )-induced CCl4-induced pulmonary tissue damage in rats. The highest TPC, TFC and TTC were found in FXBM (133.29±4.19 mg/g), ethyl acetate fraction (279.55±10.35 mg/g), and chloroform fraction (0.79±0.06 mg/g), respectively. The most potent antioxidant capacity was depicted by FXBM (29.21±2.40 µg/mg) and ethyl acetate fraction (91.16±5.51 µg/mg). The HPLC-DAD analysis revealed the predominance of gallic, chlorogenic, vanillic and ferulic acid in FXBM. The administration of CCl4 induced oxidative stress, suppressed antioxidant enzymes' activities including catalase, peroxidase, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase, and glutathione reductase. Further, it increased thiobarbituric acid reactive substances (TBARS) and H2 O2 levels, induced DNA injuries and reduced the total protein and glutathione content in lung tissues. The treatment of rats with FXBM restored these biochemical parameters to the normal level. Moreover, the histopathological studies of lung tissues demonstrated that FXBM protected rats' lung tissues from oxidative damage restoring normal lung functions. Thus, F. xanthoxyloides bark extract is recommended as adjuvant therapy as protective agent for patients with lung disorders.


Assuntos
Antioxidantes , Fraxinus , Lesão Pulmonar , Extratos Vegetais , Animais , Ratos , Antioxidantes/química , Clorofórmio/metabolismo , Clorofórmio/toxicidade , Fraxinus/química , Fraxinus/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos , Fígado/metabolismo , Pulmão/metabolismo , Estresse Oxidativo , Casca de Planta/química , Casca de Planta/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos Sprague-Dawley , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico
3.
Artigo em Inglês | MEDLINE | ID: mdl-34360388

RESUMO

Pesticide adjuvants (PAs) denote the general term for auxiliaries in pesticide preparations except for the active components. Toluene, chloroform, and trichloroethylene are the three most commonly used PAs as organic solvents. The residues of the three chemicals in the process of production and application of pesticides may endanger the ecosystem. In the present study, the mutagenicity of toluene, chloroform, and trichloroethylene as well the mixture of the three chemicals was tested by the Salmonella typhimurium reverse mutation test (Ames test) with TA97, TA98, TA100, and TA102 strains in the system with and without rat liver microsomal preparations (S9). The four tester strains have been used for more than 40 years to detect mutagenic compounds in chemicals, cosmetics, and environmental samples. The mutagenicity was detected on tester strains in the separated experiment from the three chemicals. The addition of S9 decreased the mutation ratios of toluene to four strains, except for the TA100 strain, but increased the mutation ratios of chloroform to four strains except for the TA98 strain. Trichloroethylene caused positive mutagenicity to become negative on the TA102 strain. In the mixed experiment, positive effects were detected only on the TA102 strain in the absence of S9. The addition of S9 increased the mutagenicity except for the TA102 strain. The mixture of toluene, chloroform, and trichloroethylene showed antagonism in mutagenicity to tester strains, except for the TA102 strain without S9. However, the mixture showed a synergistic effect to tester strains after adding S9 except for the TA98 strain.


Assuntos
Praguicidas , Tricloroetileno , Animais , Clorofórmio/toxicidade , Ecossistema , Testes de Mutagenicidade , Mutagênicos , Ratos , Tolueno/toxicidade , Tricloroetileno/toxicidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-32165350

RESUMO

Effects of natural stressors such as copper (Cu2+), temperature, hypoxia, chloroform and adrenaline on physiological and biochemical responses were investigated in the Mediterranean green crab Carcinus aestuarii from tidal shallow waters of Narta Lagoon, Albania. For this purpose, hemolymph glucose levels, total and differential hemocyte count, in normal and eye-stalked individuals, exposed to above mentioned stressors like, were assessed. In addition, lysosomal membrane stability was evaluated as biomarker of hemocyte toxicity, with possible implications on crab immune response. Hemolymph glucose levels were significantly increased in all treatment groups with 1.25-to 3.5-fold above baseline levels of 37.8 ± 2.7 mgdL-1. Response times were being manifested within 30-120 min following exposure and recovery happened within 2 h of restoration of pretreatment conditions. Total hemocyte count (THC) and differential hemocyte count (DCH) showed a significant decrease for all stressors, except for copper, were an increase of semi-granular hemocyte fraction were recorded. Meanwhile, significant reduction of neutral red retention time (NRRT), in both eyestalk-ablated and exposed animals, were recorded, indicated the loss of hemocyte lysosomal membrane integrity. The responsiveness of hemolymph blood levels to all stressors, the decrease in total hemocyte count, as well as the loss of lysosomal membrane integrity demonstrated that exposure to environmentally realistic stressors placed a heavy metabolic load on C. aestuarii, modulating their immune competence and overall physiological wellness. Overall, results suggest that monitoring cellular and biochemical parameters like hemolymph glucose titres, TCH, DHC and NRRT, may be useful and sensitive means of evaluating the crustacean's ability to cope with the wide variety of environmental stressors through modulation of the immune parameters.


Assuntos
Braquiúros/fisiologia , Clorofórmio/toxicidade , Cobre/toxicidade , Epinefrina/toxicidade , Hipóxia , Poluentes Químicos da Água/toxicidade , Animais , Glucose/metabolismo , Hemócitos/citologia , Hemócitos/metabolismo , Hemolinfa/metabolismo , Temperatura
5.
J Anesth Hist ; 6(4): 26-27, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33674027

RESUMO

An ex-employee of a Newark straw hat factory, 15-year-old Robert Alden Fales battered the factory's cashier Thomas Haydon on the head multiple times with a wooden staff. Fales then applied a chloroform-soaked handkerchief to Haydon's nose until the cashier stopped moving. Arrested and convicted of murder, Fales had his death sentence commuted to life imprisonment. At 23 years of age, the criminal chloroformist died in jail from tuberculosis.


Assuntos
Anestesiologia/história , Clorofórmio/história , Crime/história , Comportamento Criminoso/história , Criminosos/história , Adolescente , Clorofórmio/toxicidade , História do Século XIX , Humanos , Masculino
6.
Naunyn Schmiedebergs Arch Pharmacol ; 393(4): 573-580, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31720798

RESUMO

Chloroform has been used over decades in anesthesia before it was replaced by other volatile anesthetics like halothane or sevoflurane. Some of the reasons were inadmissible side effects of chloroform like bradycardia or neural illness. In the present study, we identified members of the G protein-activated inwardly rectifying potassium channel family (Kir3) expressed in Xenopus oocytes as potential common molecular targets for both the neural and cardiac effects of chloroform. Millimolar concentration currents representing a 1:10000 dilution of commercially available chloroform were used in laboratories that augment neuronal Kir3.1/3.2 currents as well as cardiac Kir3.1/3.4. This effect was selective and only observed in currents from Kir3 subunits but not in currents from Kir2 subunits. Augmentation of atrial Kir3.1/3.4 currents leads to an effective drop of the heart rate and a reduction in contraction force in isolated mouse atria.


Assuntos
Função Atrial/efeitos dos fármacos , Bradicardia/induzido quimicamente , Clorofórmio/toxicidade , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/fisiologia , Átrios do Coração/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Bradicardia/fisiopatologia , Células HEK293 , Humanos , Camundongos , Neurônios/fisiologia , Oócitos , Xenopus laevis
7.
Int J Biol Sci ; 15(11): 2296-2307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31595148

RESUMO

Liver is one of the most vital organs to maintain homeostasis because of its peculiar detoxification functionalities to detoxify chemicals and metabolize drugs and toxins. Due to its crucial functions, the liver is also prone to various diseases, i.e., hepatitis, cirrhosis and hepatoma, etc. Additionally, long non-coding RNAs (lncRNAs) has emerged as key regulators which are found to play important roles in transcription, splicing, translation, replication, chromatin shaping and post translational modification of proteins in living cells. However, the underlying mechanisms of biological processes mediated by lncRNA remain unclear. Here, with the aim of disclosing potential lncRNAs implicated in the biological processes in liver in response to cytotoxicity, we performed a co-expression network analysis based on the transcriptome data of the damaged liver tissue of Rattus norvegicus induced by three cytotoxic compounds (carbon tetrachloride, chloroform and thioacetamide). Our analysis unveils that many biological processes and pathways were collectively affected by the three cytotoxic compounds, including drug metabolism, oxidation-reduction process, oxidative stress, glucuronidation, liver development and flavonoid biosynthetic process, etc. Also, our network analysis has identified several highly conserved lncRNA-mRNA interactions participating in those correlated processes and pathways, implying their potential roles in response to the induced cytotoxicity in liver. Our study provides new insights into lncRNA-mRNA regulatory mechanisms in response to pathogenic cytotoxic damaging in liver and facilitates the development of lncRNA-oriented therapies for hepatic diseases in the future.


Assuntos
Fígado/efeitos dos fármacos , Fígado/metabolismo , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Clorofórmio/toxicidade , Ratos , Tioacetamida/toxicidade , Transcriptoma/efeitos dos fármacos
8.
Environ Sci Pollut Res Int ; 26(9): 8609-8622, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30707385

RESUMO

The organic toxicants formed in chlorinated water cause potential harm to human beings, and it is extensively concentrated all over the world. Various disinfection by-products (DBPs) occur in chlorinated water are genotoxic and carcinogenic. The toxicity is major concern for chlorinated DBPs which has been present more in potable water. The purpose of the work was to evaluate genotoxic properties of DBPs in Allium cepa as a plant model system. The chromosomal aberration and DNA laddering assays were performed to examine the genotoxic effect of trichloroacetic acid (TCAA), trichloromethane (TCM), and tribromomethane (TBM) in a plant system with distinct concentrations, using ethyl methanesulfonate (EMS) as positive control and tap water as negative control. In Allium cepa root growth inhibition test, the inhibition was concentration dependent, and EC50 values for trichloroacetic acid (TCAA), trichloromethane (TCM), and tribromomethane (TBM) were 100 mg/L, 160 mg/L, and 120 mg/L respectively. In the chromosome aberration assay, root tip cells were investigated after 120 h exposure. The bridge formation, sticky chromosomes, vagrant chromosomes, fragmented chromosome, c-anaphase, and multipolarity chromosomal aberrations were seen in anaphase-telophase cells. It was noticed that with enhanced concentrations of DBPs, the total chromosomal aberrations were more frequent. The DNA damage was analyzed in roots of Allium cepa exposed with DBPs (TCAA, TCM, TBM) by DNA laddering. The biochemical assays such as lipid peroxidation, H2O2 content, ascorbate peroxidase, guaiacol peroxidase, and catalase were concentration dependent. The DNA interaction studies were performed to examine binding mode of TCAA, TCM, and TBM with DNAs. The DNA interaction was evaluated by spectrophotometric and spectrofluorometric studies which revealed that TCAA, TCM, and TBM might interact with Calf thymus DNA (CT- DNA) by non-traditional intercalation manner.


Assuntos
Desinfetantes/toxicidade , Monitoramento Ambiental/métodos , Cebolas/fisiologia , Ascorbato Peroxidases/genética , Clorofórmio/toxicidade , Aberrações Cromossômicas , Dano ao DNA , Desinfecção , Água Potável , Halogenação , Humanos , Peróxido de Hidrogênio/metabolismo , Meristema/efeitos dos fármacos , Mitose , Cebolas/efeitos dos fármacos , Peroxidase , Raízes de Plantas/efeitos dos fármacos , Ácido Tricloroacético/toxicidade , Trialometanos/toxicidade
9.
Environ Sci Pollut Res Int ; 26(6): 5316-5332, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30607849

RESUMO

Chlorine is considered the most used chemical agent for water disinfection worldwide. However, water chlorination can lead to by-product generation which can be toxic to humans. The present study aimed to perform a systematic review on the toxicity of trihalomethanes (THMs) through bioindicators of cytotoxicity, genotoxicity, and mutagenicity. The results showed that studies on the effects of THMs on DNA are a current research concern for evaluating the toxicity of the pure compounds and real samples involving several types including water for recreational use, reused water, and drinking water. THMs deleterious effects have been assessed using several biosystems, where the Ames test along with experimental animal models were the most cited. A wide range of THM concentrations have been tested. Nevertheless, DNA damage was demonstrated, highlighting the potential human health risk. Among the studied THMs, chloroform presented a different action mechanism when compared with brominated THMs, with the former being cytotoxic while brominated THMs (bromodichloromethane, bromoform, and dibromochloromethane) were cytotoxic, genotoxic, and mutagenic. The described evidence in this research highlights the relevance of this topic as a human health issue. Nevertheless, research aimed to represent THMs current exposure conditions in a more accurate way would be needed to understand the real impact on human health.


Assuntos
Trialometanos/toxicidade , Animais , Clorofórmio/toxicidade , Dano ao DNA/efeitos dos fármacos , Desinfecção , Halogenação , Humanos , Testes de Mutagenicidade , Poluentes Químicos da Água/toxicidade
10.
Birth Defects Res ; 110(17): 1267-1313, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30350414

RESUMO

AIMS: We assessed the animal and epidemiological data to determine if chloroform exposure causes developmental and/or reproductive toxicity. RESULTS AND DISCUSSION: Initial scoping identified developmental toxicity as the primary area of concern. At levels producing maternal toxicity in rats and mice, chloroform caused decrements in fetal weights and associated delays in ossification. In a single mouse inhalation study, exposure to a high concentration of chloroform was associated with small fetuses and increased cleft palate. However, oral exposure of mice to chloroform at a dose 4 times higher was negative for cleft palate; multiple inhalation studies in rats were also negative. Epidemiologic data on low birth weight and small for gestational age were generally equivocal, preventing conclusions from being drawn for humans. The animal data also show evidence of very early (peri-implantation) total litter losses at very high exposure levels. This effect is likely maternally mediated rather than a direct effect on the offspring. Finally, the epidemiologic data indicate a possible association of higher chloroform exposure with lower risk of preterm birth (<37 weeks gestation). CONCLUSIONS: The available animal data suggest that exposures lower than those causing maternal toxicity should be without developmental effects in the offspring. Also, most studies in humans rely on group-level geographic exposure data, providing only weak epidemiologic evidence for an association with development outcomes and fail to establish a causal role for chloroform in the induction of adverse developmental outcomes at environmentally relevant concentrations.


Assuntos
Clorofórmio/toxicidade , Peso Fetal/efeitos dos fármacos , Exposição Materna/efeitos adversos , Reprodução/efeitos dos fármacos , Solventes/efeitos adversos , Animais , Feminino , Humanos , Recém-Nascido de Baixo Peso , Camundongos , Gravidez , Resultado da Gravidez , Ratos
11.
Neurotox Res ; 34(3): 353-362, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29667127

RESUMO

Chloroform-induced olfactory mucosal degeneration has been reported in adult rats following gavage. We used fixed-point chloroform infusions on different postnatal days (PNDs) to investigate the effects of early olfactory bilateral deprivation on the main olfactory bulbs in Sprague Dawley rats. The experimental groups included rats infused with chloroform (5 µl) or saline (sham, 5 µl) on PNDs 3 and 8, and rats not receiving infusions (control) (n = 6 in all groups). Rats receiving chloroform on PND 3 showed significant hypoevolutism when compared to those in other groups (P < 0.05). There was a complete disappearance and a significant reduction in the size of olfactory glomeruli in the PND 3 and 8 groups, respectively, when compared to the respective sham groups. Rats receiving chloroform on PND 3 had significant memory impairment (P < 0.01) and increased levels of learned helplessness (P < 0.05), as measured using the Morris water maze and tail suspension tests, respectively. GABAA receptor alpha5 subunit (α5GABAAR) expression in hippocampal neurons was significantly lower in rats receiving chloroform on PND 3 than in rats in other groups (P < 0.01), as measured using immunohistochemistry and polymerase chain reaction. There was thus a critical period for the preservation of regenerative ability in olfactory receptor neurons, during which damage and olfactory deprivation led to altered rhinencephalon structure and disappearance of olfactory glomeruli, which induced hypoevolutism. Olfactory deprivation after the critical period had no significant effect on olfactory receptor neuron regeneration, leading to reduced developmental and behavioral effects in Sprague Dawley rats.


Assuntos
Hipocampo/metabolismo , Transtornos do Olfato/patologia , Mucosa Olfatória/patologia , Neurônios Receptores Olfatórios/patologia , Receptores de GABA-A/metabolismo , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Clorofórmio/toxicidade , Depressão/etiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Elevação dos Membros Posteriores , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos do Olfato/induzido quimicamente , Mucosa Olfatória/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/genética , Privação Sensorial , Solventes/toxicidade
12.
Theranostics ; 8(4): 894-905, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29463989

RESUMO

Liver damage and fibrosis are precursors of hepatocellular carcinoma (HCC). In HCC patients, sorafenib-a multikinase inhibitor drug-has been reported to exert anti-fibrotic activity. However, incomplete inhibition of RAF activity by sorafenib may also induce paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway in malignant cells. The consequence of this effect in non-malignant disease (hepatic fibrosis) remains unknown. This study aimed to examine the effects of sorafenib on activated hepatic stellate cells (HSCs), and develop effective therapeutic approaches to treat liver fibrosis and prevent cancer development. Methods: We first examined the effects of sorafenib in combination with MEK inhibitors on fibrosis pathogenesis in vitro and in vivo. To improve the bioavailability and absorption by activated HSCs, we developed CXCR4-targeted nanoparticles (NPs) to co-deliver sorafenib and a MEK inhibitor to mice with liver damage. Results: We found that sorafenib induced MAPK activation in HSCs, and promoted their myofibroblast differentiation. Combining sorafenib with a MEK inhibitor suppressed both paradoxical MAPK activation and HSC activation in vitro, and alleviated liver fibrosis in a CCl4-induced murine model of liver damage. Furthermore, treatment with sorafenib/MEK inhibitor-loaded CXCR4-targeted NPs significantly suppressed hepatic fibrosis progression and further prevented fibrosis-associated HCC development and liver metastasis. Conclusions: Our results show that combined delivery of sorafenib and a MEK inhibitor via CXCR4-targeted NPs can prevent activation of ERK in activated HSCs and has anti-fibrotic effects in the CCl4-induced murine model. Targeting HSCs represents a promising strategy to prevent the development and progression of fibrosis-associated HCC.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Cirrose Hepática/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Nanopartículas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Receptores CXCR4/antagonistas & inibidores , Sorafenibe/administração & dosagem , Animais , Clorofórmio/toxicidade , Modelos Animais de Doenças , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/fisiologia , Cirrose Hepática/induzido quimicamente , Camundongos , Receptores CXCR4/metabolismo , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-29148923

RESUMO

Chloroform and Bromoform are two abundant trihalomethanes found in Algerian drinking water. The investigation of the mutagenic hazard of these disinfection by-products was studied by Ames test as prokaryotic bioassay to show their mutagenic effects. For this, Salmonella typhimurium TA98 and TA100 strains were employed. Both chloroform and bromoform showed a direct mutagenic effect since the number of revertant colonies gradually increase in dose-dependent manner with all concentrations tested with the two bacterial strains and these were both in the absence and presence of S9 metabolic activation. The genotoxic hazard was also studied by random amplified polymorphic DNA test on the root cells of Allium cepa as eukaryotic bioassay. DNA extracted from the roots of the onion were incubated at different concentrations of chloroform and bromoform and then amplified by polymerase chain reaction. This was based on demonstrating a major effect of disappearance of bands compared to roots incubated in the negative control (distilled water). The results showed that these two compounds affected genomic DNA by breaks although by mutations.


Assuntos
Clorofórmio/toxicidade , Desinfetantes/toxicidade , Água Potável/química , Salmonella typhimurium/genética , Dano ao DNA/efeitos dos fármacos , DNA Bacteriano/genética , Testes de Mutagenicidade , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Trialometanos/toxicidade
14.
J Environ Sci (China) ; 58: 250-261, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28774616

RESUMO

Exposure to disinfection by-products (DBP) such as trihalomethanes (THM) in swimming pools has been linked to adverse health effects in humans, but their biological mechanisms are unclear. We evaluated short-term changes in blood gene expression of adult recreational swimmers after swimming in a chlorinated pool. Volunteers swam 40min in an indoor chlorinated pool. Blood samples were drawn and four THM (chloroform, bromodichloromethane, dibromochloromethane and bromoform) were measured in exhaled breath before and after swimming. Intensity of physical activity was measured as metabolic equivalents (METs). Gene expression in whole blood mRNA was evaluated using IlluminaHumanHT-12v3 Expression-BeadChip. Linear mixed models were used to evaluate the relationship between gene expression changes and THM exposure. Thirty-seven before-after pairs were analyzed. The median increase from baseline to after swimming were: 0.7 to 2.3 for MET, and 1.4 to 7.1µg/m3 for exhaled total THM (sum of the four THM). Exhaled THM increased on average 0.94µg/m3 per 1 MET. While 1643 probes were differentially expressed post-exposure. Of them, 189 were also associated with exhaled levels of individual/total THM or MET after False Discovery Rate. The observed associations with the exhaled THM were low to moderate (Log-fold change range: -0.17 to 0.15). In conclusion, we identified short-term gene expression changes associated with swimming in a pool that were minor in magnitude and their biological meaning was unspecific. The high collinearity between exhaled THM levels and intensity of physical activity precluded mutually adjusted models with both covariates. These exploratory results should be validated in future studies.


Assuntos
Desinfetantes/toxicidade , Exposição Ambiental/análise , Expressão Gênica/efeitos dos fármacos , Piscinas , Poluentes Químicos da Água/toxicidade , Adulto , Clorofórmio/sangue , Clorofórmio/toxicidade , Desinfetantes/sangue , Exposição Ambiental/estatística & dados numéricos , Feminino , Halogenação , Humanos , Masculino , RNA , RNA Mensageiro/sangue , Natação , Trialometanos/sangue , Trialometanos/toxicidade , Poluentes Químicos da Água/sangue
15.
Exp Biol Med (Maywood) ; 242(14): 1389-1397, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28629226

RESUMO

Chronic liver injury of any etiology is the main trigger of fibrogenic responses and thought to be mediated by hepatic stellate cells. Herein, activating transcription factors like forkhead box f1 are described to stimulate pro-fibrogenic genes in hepatic stellate cells. By using a liver-specific siRNA delivery system (DBTC), we evaluated whether forkhead box f1 siRNA treatment exhibit beneficial effects in murine models of acute and chronic CCl4-induced liver injury. Systemic administration of DBTC-forkhead box f1 siRNA in mice was only sufficient to silence forkhead box f1 in acute CCl4 model, but was not able to attenuate liver injury as measured by liver enzymes and necrotic liver cell area. Therapeutic treatment of mice with DBTC-forkhead box f1 siRNA upon chronic CCl4 exposition failed to inhibit forkhead box f1 expression and hence lacked to diminish hepatic stellate cells activation or fibrosis development. As a conclusion, DBTC-forkhead box f1 siRNA reduced forkhead box f1 expression in a model of acute but not chronic toxic liver injury and showed no positive effects in either of these mice models. Impact statement As liver fibrosis is a worldwide health problem, antifibrotic therapeutic strategies are urgently needed. Therefore, further developments of new technologies including validation in different experimental models of liver disease are essential. Since activation of hepatic stellate cells is a key event upon liver injury, the activating transcription factor forkhead box f1 (Foxf1) represents a potential target gene. Previously, we evaluated Foxf1 silencing by a liver-specific siRNA delivery system (DBTC), exerting beneficial effects in cholestasis. The present study was designed to confirm the therapeutic potential of Foxf1 siRNA in models of acute and chronic CCl4-induced liver injury. DBTC-Foxf1 siRNA was only sufficient to silence Foxf1 in acute CCl4 model and did not ameliorate liver injury or fibrogenesis. This underlines the significance of the experimental model used. Each model displays specific characteristics in the pathogenic nature, time course and severity of fibrosis and the optimal time point for starting a therapy.


Assuntos
Produtos Biológicos/administração & dosagem , Terapia Biológica/métodos , Doença Hepática Induzida por Substâncias e Drogas/terapia , Clorofórmio/toxicidade , Fatores de Transcrição Forkhead/biossíntese , RNA Interferente Pequeno/administração & dosagem , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Fígado/patologia , Camundongos , Resultado do Tratamento
16.
J Water Health ; 15(3): 367-373, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28598341

RESUMO

With the increasing concerns about the harmful effects of disinfection products, the process of chlorination is becoming questionable. Bromoform and chloroform are among the most frequently occurring disinfection by-products. Haematological parameters are an important indicator of human well-being which is why the prime objective of the current study was to conduct a dose-response assessment to investigate the effects of trihalomethanes on human haematological count. Blood samples of healthy subjects were exposed to different concentrations (10, 30 and 50 µg/mL) of chloroform and bromoform in vitro to analyse how these compounds affected the haematological count with increasing dose concentrations. Headspace gas chromatography analysis was also conducted on samples to assess the difference between measured and spiked values of doses. The results indicated that the damage caused by bromoform was statistically more significant as compared to chloroform. Haemoglobin (HGB) and mean corpuscular haemoglobin concentration levels lowered as they were significantly affected (p < 0.05) by bromoform at all administered doses. It also significantly damaged platelet level at doses of 30 (p < 0.05) and 50 µg/mL (p < 0.01). Conversely, the damage caused by chloroform was statistically less significant (p > 0.05).


Assuntos
Contagem de Células Sanguíneas , Clorofórmio/toxicidade , Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Adulto , Relação Dose-Resposta a Droga , Índices de Eritrócitos/efeitos dos fármacos , Hematócrito , Humanos , Trialometanos/toxicidade , Adulto Jovem
17.
Protoplasma ; 254(4): 1607-1616, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27913906

RESUMO

Adsorption of non-polar compounds by suspended fullerene nanoaggregates (nC60) may enhance their toxicity and affect the fate, transformation, and transport of non-polar compounds in the environment. The potential of stable fullerene nanoaggregates as contaminant carriers in aqueous systems and the influence of chloromethanes (trichloromethane and dichloromethane) were studied on the midgut epithelial cells of Daphnia magna by light and electron microscopy. The size and shape of fullerene nanoaggregates were observed and measured using dynamic light scattering, transmission electron microscopy, and low vacuum scanning electron microscopy. The nC60 in suspension appeared as a bulk of aggregates of irregular shape with a surface consisting of small clumps 20-30 nm in diameter. The presence of nC60 aggregates was confirmed in midgut lumen and epithelial cells of D. magna. After in vivo acute exposure to chloromethane, light and electron microscopy revealed an extensive cytoplasmic vacuolization with disruption and loss of specific structures of D. magna midgut epithelium (mitochondria, endoplasmic reticulum, microvilli, peritrophic membrane) and increased appearance of necrotic cells. The degree of observed changes depended on the type of treatment: trichloromethane (TCM) induced the most notable changes, whereas fullerene nanoaggregates alone had no negative effects. Transmission electron microscopy also indicated increased lysosomal degradation and severe peroxidative damages of enterocyte mitochondria following combined exposure to chloromethane and fullerene nanoaggregates. In conclusion, the adsorption of chloromethane by fullerene nanoaggregates enhances their toxicity and induces peroxidative mitochondrial damage in midgut enterocytes.


Assuntos
Clorofórmio/toxicidade , Fulerenos/toxicidade , Cloreto de Metileno/toxicidade , Mitocôndrias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Células Cultivadas , Daphnia , Sinergismo Farmacológico , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Trato Gastrointestinal/citologia , Mitocôndrias/ultraestrutura , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Tamanho da Partícula
18.
Toxicol Lett ; 255: 11-23, 2016 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-27153797

RESUMO

The MetaMap(®)-Tox database contains plasma-metabolome and toxicity data of rats obtained from oral administration of 550 reference compounds following a standardized adapted OECD 407 protocol. Here, metabolic profiles for aniline (A), chloroform (CL), ethylbenzene (EB), 2-methoxyethanol (ME), N,N-dimethylformamide (DMF) and tetrahydrofurane (THF), dosed inhalatively for six hours/day, five days a week for 4 weeks were compared to oral dosing performed daily for 4 weeks. To investigate if the oral and inhalative metabolome would be comparable statistical analyses were performed. Best correlations for metabolome changes via both routes of exposure were observed for toxicants that induced profound metabolome changes. e.g. CL and ME. Liver and testes were correctly identified as target organs. In contrast, route of exposure dependent differences in metabolic profiles were noted for low profile strength e.g. female rats dosed inhalatively with A or THF. Taken together, the current investigations demonstrate that plasma metabolome changes are generally comparable for systemic effects after oral and inhalation exposure. Differences may result from kinetics and first pass effects. For compounds inducing only weak changes, the differences between both routes of exposure are visible in the metabolome.


Assuntos
Compostos de Anilina/toxicidade , Derivados de Benzeno/toxicidade , Clorofórmio/toxicidade , Dimetilformamida/toxicidade , Etilenoglicóis/toxicidade , Furanos/toxicidade , Metaboloma , Metabolômica , Testes de Toxicidade , Administração por Inalação , Administração Oral , Compostos de Anilina/administração & dosagem , Compostos de Anilina/farmacocinética , Animais , Derivados de Benzeno/administração & dosagem , Derivados de Benzeno/farmacocinética , Clorofórmio/administração & dosagem , Clorofórmio/farmacocinética , Bases de Dados Factuais , Dimetilformamida/administração & dosagem , Dimetilformamida/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação , Etilenoglicóis/administração & dosagem , Etilenoglicóis/farmacocinética , Feminino , Furanos/administração & dosagem , Furanos/farmacocinética , Exposição por Inalação , Masculino , Análise de Componente Principal , Ratos Wistar , Medição de Risco
19.
Food Chem Toxicol ; 91: 1-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26945614

RESUMO

Lepidopterists use substantial volumes of solvents, such as chloroform, 1,1,2,2-tetrachloroethane and xylene, in their traps when collecting faunistic and phenological data. A majority of them are citizen scientists and thus in part not identified by occupational healthcare as being at risk due to solvent handling. We surveyed the extent of solvent use, the frequency and extent of potential exposure and the safety precautions taken in trapping and catch handling by Finnish lepidopterists. Chloroform and 1,1,2,2-tetrachloroethane were the most frequently used anaesthetics. Potential for exposure prevailed during trap maintenance and exploration and catch sorting. Adequate protection against vapours or spills was worn by 17% during trap exploration. Subjects completed a median of 100 trap explorations per season. Dermal or mucosal spills were recorded at a median rate of one spill per ten (chloroform) to 20 (1,1,2,2-tetrachloroethane and xylene) trap explorations. Median annual cumulative durations of 8 and 20 h of exposure to chloroform and 1,1,2,2-tetrachloroethane at levels above odour detection threshold were reported. Subjective adverse findings possibly related solvents had been noticed by 24 (9.8%) lepidopterists. All the events had been mild to moderate. No factor predicting unsafe procedures or adverse reactions was recorded despite thorough statistical testing.


Assuntos
Carcinógenos/toxicidade , Clorofórmio/toxicidade , Entomologia , Etano/análogos & derivados , Hidrocarbonetos Clorados/toxicidade , Lepidópteros , Exposição Ocupacional , Animais , Etano/toxicidade , Finlândia , Humanos , Recursos Humanos
20.
Med Tr Prom Ekol ; (8): 24-8, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26596112

RESUMO

The study covered genetically determined lipid metabolism disorders due to oral intake of technogenic hyperchlorination drinkable water products. Findings are that overweight and obese children in a main group appeared to have serum chloroform level 2.3 times higher than that in a reference group. In oral intake of hyperchlorination drinkable water products, the study revealed main genes having polymorphism associated with endocrine disorders: overweight and obesity--APOE, PPARG, HTR2A, characterizing antioxidant system state--SOD2 and detoxication--SULTA. Polymorphism of candidate genes HTR2A and SOD2 was characterized by increased occurrence of mutant homo-- and heterozygous genotype, relative risk of pathologic allele presence in population exceeded the refrence group values. Probability of increased serum serotonin and lower Cu/Zn in children with mutant homozygous genotype HTR2A and SOD2 is 1.2-1.3 times higher than in those with heterozygous and normal homozygous genotypes.


Assuntos
Clorofórmio/toxicidade , Predisposição Genética para Doença , Obesidade Infantil/induzido quimicamente , Receptor 5-HT2A de Serotonina/genética , Superóxido Dismutase/genética , Poluentes Químicos da Água/toxicidade , Criança , Clorofórmio/sangue , Água Potável/química , Feminino , Heterozigoto , Homozigoto , Humanos , Masculino , Obesidade Infantil/genética , Polimorfismo Genético , Poluentes Químicos da Água/sangue
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