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1.
Exp Dermatol ; 33(8): e15156, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39133032

RESUMO

This study investigates the carcinogenic potential of chronic dermal exposure (16 weeks) to sulfuric acid (SA) in immunocompetent mice. Clinical assessments, histopathological analyses, immunohistochemical analyses and biochemical assays were conducted to evaluate skin irritation, oxidative stress biomarkers and the potential carcinogenic effect of SA. Results indicated that prolonged exposure to SA leads to various alterations in skin structure, notably inflammation, preneoplastic and neoplastic proliferation in hair follicles, as well as hyperkeratosis and acanthosis, resulting in an increased epidermal thickness of 98.50 ± 21.6 µm. Immunohistochemistry analysis further corroborates these observations, showcasing elevated nuclear expression of p53 and Ki-67, with a significant mitotic index of (57.5% ± 2.5%). Moreover, biochemical analyses demonstrate that SA induces lipid peroxidation in the skin, evidenced by a high level of Malondialdehyde and a consequential reduction in catalase activity. These findings suggest that prolonged exposure to SA can induce skin neoplasms, highlighting the need for stringent safety measures in environments where SA is frequently used. This study underscores the potential occupational health risks associated with SA exposure.


Assuntos
Neoplasias Cutâneas , Ácidos Sulfúricos , Animais , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/metabolismo , Camundongos , Ácidos Sulfúricos/efeitos adversos , Ácidos Sulfúricos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Feminino , Malondialdeído/metabolismo , Imunocompetência , Catalase/metabolismo , Pele/patologia , Pele/metabolismo , Pele/efeitos dos fármacos , Antígeno Ki-67/metabolismo , Proteína Supressora de Tumor p53/metabolismo
2.
Forensic Sci Med Pathol ; 16(3): 481-488, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32304016

RESUMO

Vitriolage (acid attack) involves an intentional act of violence in which any corrosive is thrown onto the face and body of a person with the intention of disfiguring them. The most common type of corrosive used in these attacks is sulfuric acid (oil of vitriol) hence the name "vitriolage". Sulfuric acid is a strong acid/corrosive and has a toxic nature that is capable of causing bodily injuries leading to damage to mucous membranes, tissues and skin with blindness, burning, and scars often leading to significant disfigurement with temporary or permanent disability. The main reasons for acid attacks are marriage refusal, rejection of love proposals, dowry issues and male aggression. Acid attacks have horrendous physical, social, psychological and economic effects on victims. This review will delineate the various legal provisions relating to acid attacks with special reference to the recent Indian Criminal Law Amendment Act of 2013 which addressed the issue of these attacks specifically by making it a separate offence in the Indian Penal Code under sections 326 A and B. The Bangladesh Acid Offences Prevention Act 2002 and Acid Crime Control Act, 2002, and legislation and policies combating acid attacks in Cambodia, Nepal and Pakistan will also be mentioned. Additionally, the paper will discuss the role of the judiciary in South Asia by focusing on other landmark judgments and decisions and throw light on the campaign in India namely "Stop Sale Acid" aimed at stopping the unrestricted sale of acid. Finally, further suggestions are proposed to assist in combating this heinous crime.


Assuntos
Queimaduras Químicas/etiologia , Abuso Físico , Ácidos Sulfúricos/toxicidade , Cegueira/etiologia , Queimaduras Químicas/psicologia , Cicatriz/etiologia , Vítimas de Crime/legislação & jurisprudência , Vítimas de Crime/psicologia , Pessoas com Deficiência , Traumatismos Faciais/etiologia , Medicina Legal , Humanos , Internacionalidade , Motivação
3.
Ecotoxicol Environ Saf ; 160: 154-161, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29803190

RESUMO

The influence of acid rain on plant growth includes direct effects on foliage as well as indirect soil-mediated effects that cause a reduction in root growth. In addition, the concentration of NO3- in acid rain increases along with the rapid growth of nitrogen deposition. In this study, we investigated the impact of simulated acid rain with different SO42-/NO3- (S/N) ratios, which were 1:0, 5:1, 1:1, 1:5 and 0:1, on Chinese fir sapling growth from March 2015 to April 2016. Results showed that Chinese fir sapling height growth rate (HGR) and basal diameter growth rate (DGR) decreased as acid rain pH decreased, and also decreased as the percentage of NO3- increased in acid rain. Acid rain pH significantly decreased the Chlorophyll a (Chla) and Chlorophyll b (Chlb) content, and Chla and Chlb contents with acid rain S/N 1:5 were significantly lower than those with S/N 1:0 at pH 2.5. The chlorophyll fluorescence parameters, maximal efficiency of Photosystem II photochemistry (Fv/Fm) and non-photochemical quenching coefficient (NPQ), with most acid rain treatments were significantly lower than those with CK treatments. Root activities first increased and then decreased as acid rain pH decreased, when acid rain S/N ratios were 1:1, 1:5 and 0:1. Redundancy discriminant analysis (RDA) showed that the Chinese fir DGR and HGR had positive correlations with Chla, Chlb, Fv/Fm ratio, root activity, catalase and superoxide dismutase activities in roots under the stress of acid rain with different pH and S/N ratios. The structural equation modelling (SEM) results showed that acid rain NO3- concentration and pH had stronger direct effects on Chinese fir sapling HGR and DGR, and the direct effects of acid rain NO3- concentration and pH on HGR were lower than those on DGR. Our results suggest that the ratio of SO42- to NO3- in acid rain is an important factor which could affect the sustainable development of monoculture Chinese fir plantations in southern China.


Assuntos
Chuva Ácida/toxicidade , Cunninghamia/efeitos dos fármacos , Ácido Nítrico/toxicidade , Ácidos Sulfúricos/toxicidade , China , Clorofila/metabolismo , Clorofila A , Cunninghamia/crescimento & desenvolvimento , Cunninghamia/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
4.
Ecotoxicol Environ Saf ; 148: 834-841, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29197798

RESUMO

A study was conducted to characterize marigold stress response to polycyclic aromatic hydrocarbons (PAHs) (oxidative stress inducers) with and without sulfuric acid (S.Acid; pH 3) (acid-stress inducer), and to evaluate reactive oxygen species (ROS) scavenging activity of mannitol (Mann). Marigold (Calendula officinalis) seedlings were grown in a greenhouse and fumigated with fluoranthene (FLU), phenanthrene (PHE), Mann, and S.Acid individually and in various combinations for 40 days. Various physiological and biochemical parameters among others were analyzed using standard methods. The results revealed that fumigation of FLU induced oxidative stress to the plants via ROS generation leading to negative effects on photosynthesis at near saturating irradiance (Amax), stomatal conductance (Gs), internal carbon dioxide concentration (Ci), leaf water relations and chlorophyll pigments. Significant per cent inhibition of Amax (54%), Gs (86%) and Ci (32%), as well as per cent reductions in chlorophyll a (Chl.a) (33%), Chl.b (34%), and total chlorophyll (Tot. Chl) (48%) contents were recorded in FLU fumigated treatment in comparison to control. Combination of Mann with FLU scavenged the generated ROS and substantially lowered the oxidative stress on the plants hence all the measured parameters were not significantly different from control. PHE fumigation had varied effects on marigold plants and was not as deleterious as FLU. Combined fumigation of S.Acid with both the PAHs had significant negative effect on leaf water relations, and positive effect on fresh and turgid weight of the plants but had no effect on the other measured parameters. The lowest proline contents and highest catalase and ascorbate peroxidase activities in FLU fumigated plants further confirmed that oxidative stress was imposed via the generation of ROS. From the results, it is evident that Mann could be an efficient scavenger of ROS-generated by FLU in the marigold plants. We recommend Mann to be widely used for the protection of higher plants from FLU-generated stress in the urban areas.


Assuntos
Calendula/efeitos dos fármacos , Fumigação , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Calendula/crescimento & desenvolvimento , Calendula/metabolismo , Clorofila/metabolismo , Sinergismo Farmacológico , Fluorenos/toxicidade , Manitol/toxicidade , Fenantrenos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Ácidos Sulfúricos/toxicidade
5.
Crit Rev Toxicol ; 46(3): 241-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26515429

RESUMO

BACKGROUND: Asthmatic individuals constitute a large sub-population that is often considered particularly susceptible to the deleterious effects of inhalation of airborne chemicals. However, for most such chemicals information on asthmatics is lacking and inter-individual assessment factors (AFs) of 3-25 have been proposed for use in the derivation of health-based guideline values. OBJECTIVE: To evaluate available information in attempt to determine whether a general difference in airway response during short-term exposure between healthy and asthmatic individuals can be identified, and whether current AFs for inter-individual variability provide sufficient protection for asthmatics. METHODS: After performing systematic review of relevant documents and the scientific literature estimated differential response factors (EDRF) were derived as the ratio between the lowest observed adverse effect levels for healthy and asthmatic subjects based on studies in which both groups were tested under the same conditions. Thereafter, the concentration-response relationships for healthy and asthmatic subjects exposed separately to four extensively tested chemicals (nitrogen dioxide, ozone, sulfuric acid, sulfur dioxide) were compared on the basis of combined data. Finally, a Benchmark Concentration (BMC) analysis was performed for sulfur dioxide. RESULTS: We found evidence of higher sensitivity among asthmatics (EDRF > 1) to 8 of 19 tested chemicals, and to 3 of 11 mixtures. Thereafter, we confirmed the higher sensitivity of asthmatics to sulfuric acid and sulfur dioxide. No difference was observed in the case of ozone and nitrogen dioxide. Finally, our BMC analysis of sulfur dioxide indicated a ninefold higher sensitivity among asthmatics. CONCLUSION: Although experimental data are often inconclusive, our analyses suggest that an AF of 10 is adequate to protect asthmatics from the deleterious respiratory effects of airborne chemicals.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Asma/diagnóstico , Asma/induzido quimicamente , Asma/prevenção & controle , Bases de Dados Factuais , Humanos , Dióxido de Nitrogênio/toxicidade , Ozônio/toxicidade , Dióxido de Enxofre/toxicidade , Ácidos Sulfúricos/toxicidade
6.
Inhal Toxicol ; 28(4): 155-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26986950

RESUMO

Epidemiological studies suggest that diabetics may be more susceptible to the adverse health effects from exposure to high ambient concentrations of ozone, the primary oxidant gas in photochemical smog. While increased morbidity and mortality from ozone inhalation has been linked to disruption of normal cardiovascular and airway functions, potential effects on glucose and insulin homeostasis are not understood. We tested the hypothesis that ozone exposure would worsen metabolic homeostasis in KKAy mice, a genetic diabetic animal model. Male KKAy mice were exposed to 0.5 ppm ozone for 13 consecutive weekdays, and then assessed for airway, adipose and systemic inflammation, glucose homeostasis, and insulin signaling. Ozone exposure increased plasma TNFα, as well as expression of VCAM-1, iNOS and IL-6 in both pulmonary and adipose tissues. Pro-inflammatory CD11b(+)Gr-1(lo)7/4(hi) macrophages were increased by 200% in adipose tissue, but unchanged in blood. Interestingly, glucose levels were not significantly different in the insulin tolerance test between air- and ozone-exposed mice, whereas fasting insulin levels and HOMA-IR in ozone-exposed animals were significantly reduced. These changes were accompanied by increased insulin signaling in skeletal muscle and liver, but not adipose tissues. Ozone also caused decrease in body weight and plasma leptin. Our results show that in addition to marked local and systemic inflammation, ozone increases insulin sensitivity that may be related to weight loss/leptin sensitization-dependent mechanisms in KKAy mice, warranting further study on the role of hyperglycemia in mediating cardiometabolic effects of ozone inhalation.


Assuntos
Diabetes Mellitus/metabolismo , Inflamação/induzido quimicamente , Ácidos Sulfúricos/toxicidade , Adiponectina/sangue , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Administração por Inalação , Animais , Glicemia/análise , Diabetes Mellitus/sangue , Modelos Animais de Doenças , Inflamação/sangue , Inflamação/metabolismo , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo
7.
Ceylon Med J ; 60(1): 25-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25804916

RESUMO

Ingestion of corrosives with accidental or suicidal intent is a common problem in Sri Lanka. Management options and outcomes of corrosive injuries on stomach are not well documented in our setting. The clinical presentation, complications and management outcomes of nine patients with corrosive injury to stomach are presented. Gastric outlet obstruction seen in majority, was managed with bypass procedure (n=5) or resection (n=4). The outcomes of management were successful with both methods.


Assuntos
Queimaduras Químicas/cirurgia , Cáusticos/toxicidade , Obstrução da Saída Gástrica/cirurgia , Estômago/lesões , Ácido Acético/toxicidade , Adolescente , Adulto , Queimaduras Químicas/complicações , Estudos de Coortes , Ingestão de Alimentos , Feminino , Gastrectomia , Derivação Gástrica , Obstrução da Saída Gástrica/etiologia , Humanos , Masculino , Ácido Nítrico/toxicidade , Estudos Retrospectivos , Sri Lanka , Estômago/cirurgia , Gastropatias/etiologia , Gastropatias/cirurgia , Ácidos Sulfúricos/toxicidade , Adulto Jovem
8.
Bull Exp Biol Med ; 158(6): 827-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25900610

RESUMO

We analyzed ultrastruciture of the cell populations in the prostate gland in chronic nonbacterial prostatitis in a chemical industry worker. It was shown that ultrastructural reorganization of the epithelium consisted in reduction of the secretory compartment of the cytoplasm and dystrophic-degenerative changes in cell organelles. Endothelial cells of the capillaries showed signs of significant degeneration and low intensity of micropinocytosis. Most of the smooth muscle cells underwent dystrophic-degenerative modifications of ultrastructural elements. The dominance of degenerative cell changes in the epithelial and stromal cell populations along with intensification of collagen formation in the absence of inflammatory elements allows us to interpret this pathological condition of the prostate gland as prostate pathology of occupational or mixed genesis.


Assuntos
Próstata/ultraestrutura , Adulto , Indústria Química/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/efeitos dos fármacos , Prostatite/induzido quimicamente , Prostatite/patologia , Ácidos Sulfúricos/toxicidade
9.
Am J Forensic Med Pathol ; 35(2): 109-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24457574

RESUMO

The present study is a retrospective analysis of 13 cases of deaths, which resulted from throwing of corrosives over the body. The cases were autopsied at the Department of Forensic Medicine, Maulana Azad Medical College & Associated Hospitals, Delhi, India, during a period of 13 years from July 1998 to June 2011. The cases represented approximately 0.1% of all autopsy cases during the same period. Data were analyzed with regard to the age, sex, place of occurrence, pattern of injury, survival period, and cause of death. Of these cases, 8 (61.54%) were male, and 5 (38.46%) were female. The most common age group of the victim was 21 to 30 years (46.15%). Six of the victims were attacked on the road side. Face and thorax were involved in all cases (100%). The average total body surface area of burn was 56.69%.The mean survival period was 28.2 days. In 53.85% of cases, the cause of death was septicemia.


Assuntos
Queimaduras Químicas/mortalidade , Cáusticos/toxicidade , Vítimas de Crime/estatística & dados numéricos , Homicídio/estatística & dados numéricos , Ácidos Sulfúricos/toxicidade , Acidentes/mortalidade , Adulto , Distribuição por Idade , Queimaduras Químicas/patologia , Criança , Pré-Escolar , Traumatismos Faciais/etiologia , Traumatismos Faciais/mortalidade , Feminino , Patologia Legal , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Sepse/etiologia , Sepse/mortalidade , Distribuição por Sexo , Traumatismos Torácicos/etiologia , Traumatismos Torácicos/mortalidade , Adulto Jovem
10.
Bull Exp Biol Med ; 157(3): 395-400, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25065323

RESUMO

The structural characteristics of the prostate and the blood flow in the organ were studied in chemical plant workers suffering from chronic prostatitis. The prostate echostructure was characterized by vast zones of fibrosis and calcinosis, the hemodynamic ultrasonic parameters were low. Degenerative changes in the acinar structures and stromal fibrosis predominated in the biopsy specimens, these shifts were the most pronounced in the peripheral and transitory zones. Foci of common and small-acinar degeneration of the glands, abundant concrements, and significant collagenization with periglandular and perivascular sclerosis without or with slight inflammatory infiltration were detected. We hypothesize that long exposure to adverse factors of sulfuric acid manufacture contributed to the development of pathological changes in the prostate.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Exposição Ocupacional , Próstata/patologia , Prostatite/etiologia , Ácidos Sulfúricos/toxicidade , Adulto , Aerossóis , Idoso , Indústria Química , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/irrigação sanguínea , Próstata/diagnóstico por imagem , Prostatite/diagnóstico por imagem , Prostatite/epidemiologia , Fluxo Sanguíneo Regional , Ultrassonografia , Adulto Jovem
11.
Bull Environ Contam Toxicol ; 88(6): 1009-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22467059

RESUMO

An image analysis biomonitoring system was used to evaluate sublethal effects of pH on the mean swimming velocity of zebrafish. Responses to stress were tested comparing individual and group responses. Group analysis indicated no effect for all acid pH and for pH 9.0-9.5. Individual analysis indicated behavioral differences for most acid pH and higher than 9.5. Sensitivity to sublethal pH was best assessed when using individual analysis. Zebrafish decreased hyperactivity and increased hypoactivity with more acid or alkaline pH. Individual approach allowed to determine hyperactivity or hypoactivity and the species' thresholds of exposure, which is critical for the management of impairments.


Assuntos
Comportamento Animal/efeitos dos fármacos , Modelos Biológicos , Poluentes Químicos da Água/toxicidade , Animais , Feminino , Concentração de Íons de Hidrogênio , Masculino , Modelos Químicos , Comportamento Social , Hidróxido de Sódio/toxicidade , Ácidos Sulfúricos/toxicidade , Poluentes Químicos da Água/química , Peixe-Zebra
14.
Sci Rep ; 10(1): 1919, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024949

RESUMO

Biosecurity protocols designed to prevent the spread of invasive alien species (IAS) are now an essential aspect of IAS management. However, the effectiveness of various biosecurity treatments requires further exploration. Killer shrimp, Dikerogammarus villosus, a notoriously high impact and ecosystem destabilising invader, has rapidly spread across Europe, and is of concern to invade Northern America. In this study, we examine the effectiveness of three commonly used, broad-spectrum disinfectants to cause mortality of D. villosus: Virasure Aquatic, Virkon Aquatic, and Virkon S. Immersion and spray treatments of 1%, 2% and 4% disinfectant solutions were examined for applications of up to 300 secs immersion and for up to ten consecutive sprays. Furthermore, we assessed the effectiveness of steam (≥100 °C) treatments for up to 120 secs. For all disinfectants, immersion in 1% solutions caused 100% mortality at ≥120 secs. At higher concentrations, shorter immersion times caused complete mortality: 60 and 15 secs for 2% and 4% solutions, respectively. Five sprays of 2% and 4% solutions resulted in 100% mortality, for all disinfectants. Direct steam exposure was highly effective, with complete D. villosus mortality occurring at ≥10 secs. Overall, brief exposure to broad-spectrum disinfectants and direct steam could be used to limit D. villosus spread.


Assuntos
Anfípodes/efeitos dos fármacos , Descontaminação/métodos , Desinfetantes/toxicidade , Espécies Introduzidas , Vapor , Animais , Água Doce , Peróxidos/toxicidade , Ácidos Sulfúricos/toxicidade , Fatores de Tempo
15.
Chemosphere ; 240: 124961, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574433

RESUMO

Acid mine drainage (AMD) is a sulfuric discharge containing metals and particulates that can spread to nearby water sources, imposing toxicity and physical stress to living things. We have shown that vetiver grass (Chrysopogon zizanioides) is capable of tolerating and treating AMD-impacted water from the abandoned Tab-Simco mining site from southern Illinois, though little is known about its tolerance mechanisms. We conducted metabolomic analyses of vetiver shoots and roots after relatively short- and long-term periods of exposure to Tab-Simco AMD. The metabolic shift of vetiver shoots was dramatic with longer-term AMD exposure, including upregulation of amino acid and glutathione metabolism, cellular respiration and photosynthesis pathways, with downregulation of phosphorylated metabolites. Meanwhile, the roots demonstrated drastic downregulation of phospholipids and phosphorylated metabolites, cellular respiration, glyoxylate metabolism, and amino acid metabolism. Vetiver accumulated ornithine and oxaloacetate in the shoots, which could function for nitrogen storage and various intracellular functions, respectively. Organic acids and glutathione were secreted from the roots for rhizospheric metal-chelation, whereas phosphorylated metabolites were recycled for phosphorus. These findings reveal AMD-induced metabolic shifts in vetiver grass, which are seemingly unique in comparison to independent abiotic stresses reported previously.


Assuntos
Biodegradação Ambiental , Vetiveria/metabolismo , Poluentes do Solo/análise , Ácidos Sulfúricos/análise , Aminoácidos/metabolismo , Vetiveria/química , Glutationa/metabolismo , Illinois , Metais/análise , Metais/toxicidade , Minerais/metabolismo , Mineração , Ornitina/metabolismo , Ácido Oxaloacético/metabolismo , Fosfolipídeos/biossíntese , Fotossíntese , Raízes de Plantas/metabolismo , Poluentes do Solo/toxicidade , Ácidos Sulfúricos/toxicidade
16.
Toxicol Appl Pharmacol ; 239(3): 224-32, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19481103

RESUMO

Engineered carbon nanotubes are being developed for a wide range of industrial and medical applications. Because of their unique properties, nanotubes can impose potentially toxic effects, particularly if they have been modified to express functionally reactive chemical groups on their surface. The present study was designed to evaluate whether acid functionalization (AF) enhanced the cardiopulmonary toxicity of single-walled carbon nanotubes (SWCNT) as well as control carbon black particles. Mice were exposed by oropharyngeal aspiration to 10 or 40 microg of saline-suspended single-walled carbon nanotubes (SWCNTs), acid-functionalized SWCNTs (AF-SWCNTs), ultrafine carbon black (UFCB), AF-UFCB, or 2 microg LPS. 24 hours later, pulmonary inflammatory responses and cardiac effects were assessed by bronchoalveolar lavage and isolated cardiac perfusion respectively, and compared to saline or LPS-instilled animals. Additional mice were assessed for histological changes in lung and heart. Instillation of 40 microg of AF-SWCNTs, UFCB and AF-UFCB increased percentage of pulmonary neutrophils. No significant effects were observed at the lower particle concentration. Sporadic clumps of particles from each treatment group were observed in the small airways and interstitial areas of the lungs according to particle dose. Patches of cellular infiltration and edema in both the small airways and in the interstitium were also observed in the high dose group. Isolated perfused hearts from mice exposed to 40 microg of AF-SWCNTs had significantly lower cardiac functional recovery, greater infarct size, and higher coronary flow rate than other particle-exposed animals and controls, and also exhibited signs of focal cardiac myofiber degeneration. No particles were detected in heart tissue under light microscopy. This study indicates that while acid functionalization increases the pulmonary toxicity of both UFCB and SWCNTs, this treatment caused cardiac effects only with the AF-carbon nanotubes. Further experiments are needed to understand the physico-chemical processes involved in this phenomenon.


Assuntos
Poluentes Atmosféricos/toxicidade , Traumatismo por Reperfusão Miocárdica/induzido quimicamente , Nanotubos de Carbono/toxicidade , Pneumonia/induzido quimicamente , Fuligem/toxicidade , Poluentes Atmosféricos/química , Animais , Contagem de Células Sanguíneas , Líquido da Lavagem Broncoalveolar/química , Feminino , Hemodinâmica/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Camundongos , Camundongos Endogâmicos , Microscopia Eletrônica de Transmissão , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Nanotubos de Carbono/química , Necrose , Neutrófilos/citologia , Ácido Nítrico/química , Ácido Nítrico/toxicidade , Tamanho da Partícula , Pneumonia/sangue , Pneumonia/patologia , Fuligem/química , Ácidos Sulfúricos/química , Ácidos Sulfúricos/toxicidade , Propriedades de Superfície
17.
Inhal Toxicol ; 21(8): 659-67, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19558223

RESUMO

Numerous industrial applications for man-made nanoparticles have been proposed. Interactions of nanoparticles with agents in the atmosphere may impact human health. We tested the postulate that in vitro exposures of respiratory epithelial cells to airborne magnetic nanoparticles (MNP; Fe(3)O(4)) with and without a secondary organic aerosol (SOA) and an inorganic acid could affect iron homeostasis, oxidative stress, and interleukin (IL)-8 release. Cell iron concentrations were increased after exposures to MNP and values were further elevated with co-exposures to either SOA or inorganic acid. Increased expression of ferritin and elevated levels of RNA for DMT1, proteins for iron storage and transport respectively, followed MNP exposures, but values were significant for only those with co-exposures to inorganic acid and organic aerosols. Cell iron concentration corresponded to a measure of oxidative stress in the airway epithelial cells; MNP with co-exposures to SOA and inorganic acid increased both available metal and indices of oxidant generation. Finally, the release of a proinflammatory cytokine (i.e. IL-8) by the exposed cells similarly increased with cell iron concentration. We conclude that MNP can interact with a SOA and an inorganic acid to present metal in a catalytically reactive state to cultured respiratory cells. This produces an oxidative stress to affect a release of IL-8.


Assuntos
Poluentes Atmosféricos/toxicidade , Materiais Revestidos Biocompatíveis/toxicidade , Células Epiteliais/efeitos dos fármacos , Óxido Ferroso-Férrico/toxicidade , Indicadores e Reagentes/toxicidade , Compostos Orgânicos/toxicidade , Ácidos Sulfúricos/toxicidade , Aerossóis , Poluentes Atmosféricos/metabolismo , Brônquios/citologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/metabolismo , Combinação de Medicamentos , Células Epiteliais/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Óxido Ferroso-Férrico/metabolismo , Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Humanos , Indicadores e Reagentes/metabolismo , Interleucina-8/metabolismo , Ferro/análise , Ferro/metabolismo , Compostos Orgânicos/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo , Ácidos Sulfúricos/metabolismo
18.
Plant Physiol Biochem ; 144: 118-126, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31563092

RESUMO

As nitrogen deposition increases, acid rain is gradually shifting from sulfuric acid rain (SAR) to nitric acid rain (NAR). Acid rain can severely affect plant growth, damage ecosystems, and reduce biodiversity. Thus, a shift in acid rain type presents another challenge to the conservation of endangered plant species. We investigated the effect of three acid rain types (SAR, mixed acid rain [MAR], and NAR) and pH on the growth of an endangered Chinese endemic tree, Horsfieldia hainanensis Merr., using simulated rain in a greenhouse environment. Over nine months, growth indices, chlorophyll content, antioxidant enzyme activity, malondialdehyde content, and chlorophyll fluorescence parameters were investigated for treated and control saplings. The results indicated that at a pH of 5.6, H. hainanensis could adapt to SAR and MAR, but NAR inhibited below-ground growth. At a pH of 2.5 and 4.0, SAR inhibited stem and leaf biomass accumulation, whereas NAR inhibited root biomass accumulation and altered root morphology. MAR had intermediary effects between those of SAR and NAR. Adverse effects on leaf physiology were reduced as the rain type shifted from SAR to NAR; however, roots were increasingly adversely affected. Our results suggest that conservation efforts for H. hainanensis should shift from an above-ground to a below-ground focus as acid rain transitions toward NAR.


Assuntos
Chuva Ácida/toxicidade , Myristicaceae/fisiologia , Ácido Nítrico/toxicidade , Ácidos Sulfúricos/toxicidade , Árvores/fisiologia , China , Ecossistema , Concentração de Íons de Hidrogênio , Myristicaceae/efeitos dos fármacos , Árvores/efeitos dos fármacos
19.
Inhal Toxicol ; 20(7): 665-70, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18464054

RESUMO

The objectives of this study were to examine the respiratory irritancy of boron trifluoride (BF(3)) and fluorosulfonic acid (FSA) following acute inhalation exposure. Testing was conducted using groups of 10 male and 10 female rats (BF(3)) or groups of 6 male rats (FSA). Rats were exposed for a single 4-h period (BF(3)) or a single 1-h period (FSA) and necropsied 1 or 14 days after exposure (BF(3)) or 14 days after exposure (FSA). Measurements consisted of clinical signs, body weight, kidney and lung weight, histopathology (BF(3)), and breathing parameters (FSA) and were used to evaluate the possible irritating effects of these compounds. The results indicated treatment-related findings in the larynx and trachea in the rats exposed to 74.4 mg/m(3) BF(3), consisting of ventral cartilage necrosis, hemorrhage, and an increase in ventral epithelial hyperplasia and ventral inflammatory cell inflammation 24 h postexposure. In the animals sacrificed 14 days postexposure, the only notable observation was ventral cartilage necrosis, present in 2 animals. The next lower level tested, 24.6 mg/m(3) BF, was considered a no-observed-adverse-effects level (NOAEL). A concentration of 4125 mg/m(3) FSA resulted in a clearly decreased breathing rate during and shortly after exposure with 67% (4/6) mortality on days 5-9 after exposure. A concentration of 845 mg/m(3) FSA resulted in only minor signs of irritation, consisting of slight changes in breathing pattern shorlty after exposure. The results of the present 4-h inhalation study with BF(3) indicated that respiratory irritation was present at a level of 74.4 mg/m(3) whereas 24.6 mg/m(3) was a NOAEL. A single 1-h exposure to 845 mg/m(3) FSA resulted in only minor signs of respiratory irritation, indicating that on a mass basis FSA is no more toxic or irritating than hydrogen fluoride (HF) or sulfuric acid.


Assuntos
Boranos/toxicidade , Fluoretos/toxicidade , Irritantes/toxicidade , Doenças Respiratórias/induzido quimicamente , Ácidos Sulfúricos/toxicidade , Animais , Feminino , Masculino , Ratos , Ratos Sprague-Dawley , Mecânica Respiratória/efeitos dos fármacos , Doenças Respiratórias/patologia , Testes de Toxicidade Aguda
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