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1.
Int Endod J ; 50(3): 215-228, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26863893

RESUMO

AIM: To compare the clinical and radiographic efficacy of Biodentine™ , ProRoot® White Mineral Trioxide Aggregate (WMTA) and Tempophore™ as pulpotomy medicaments in the treatment of carious primary molars. METHODOLOGY: A parallel-design, randomized controlled trial was developed. Patients above 3 years of age with carious primary teeth with vital pulps without spontaneous pain or history of swelling were included. Fifty-eight patients (82 teeth) with a mean age of 4.79 ± 1.23 years were included. The teeth were randomized, blinded and allocated to one of the three groups (Biodentine™ , ProRoot® WMTA or Tempophore™ ) for pulpotomy treatment. All teeth were followed up clinically and radiographically (after 6, 12 and 18 months) by two blinded calibrated investigators. A generalized estimating equation (GEE), Wald chi-square test and an intention-to-treat analysis (ITT) with 'last carried forward' approach were performed using Statistical Package for Social Sciences v 21.0 (IBM Corp., Armonk, NK, USA). RESULTS: Forty-six patients and 69 teeth were available for follow-up after 18 months. Clinical success (radiographic success in parenthesis) was 95.24% (94.4%), 100% (90.9%) and 95.65% (82.4%) in the Biodentine™ , ProRoot® WMTA and Tempophore™ groups, respectively, but the difference was not significant. Pulp canal obliteration was significantly different amongst the experimental groups as the Biodentine™ group exhibited significantly more pulp canal obliteration when compared to the ProRoot® WMTA group at 6 months (P = 0.008) and 18 months (P = 0.003). CONCLUSIONS: After 18-month follow-up, there was no significant difference between Biodentine™ in comparison with ProRoot® WMTA or Tempophore™ .


Assuntos
Cárie Dentária/terapia , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Pulpotomia , Compostos de Alumínio , Compostos de Cálcio , Criança , Pré-Escolar , Creosoto , Cárie Dentária/diagnóstico por imagem , Combinação de Medicamentos , Feminino , Seguimentos , Humanos , Hidrocarbonetos Iodados , Análise de Intenção de Tratamento , Masculino , Dente Molar , Óxidos , Radiografia Dentária , Silicatos , Timol , Dente Decíduo , Resultado do Tratamento
2.
Stomatologiia (Mosk) ; 93(2): 10-3, 2014.
Artigo em Russo | MEDLINE | ID: mdl-24781120

RESUMO

The aim of the current study was to assess antibacterial and cytotoxic properties of Biodentine (Septodont), Rootdent (TehnoDent) and adhesive Futurabond НР (Voco). Two lines of experiments were carried out using cements water solutions and firm tablet-like samples (made by means of special pattern). Citotoxic activity was tested on NCTC L929 mice line fibroblasts culture. All the examined materials showed antibacterial activity against E. coli, S. aureus, C. albiсans, St. faecalis, mostly evident in Futurabond and the poorest in Biodentine samples. As for cytotoxic properties, Biodentine proved not to suppress metabolic activity stimulating odontotropic impact. The results confirm the analyzed materials to be a useful tool for deep caries lesions and initial pulpitis treatment.


Assuntos
Anti-Infecciosos/farmacologia , Creosoto/farmacologia , Polpa Dentária/microbiologia , Hidrocarbonetos Iodados/farmacologia , Metacrilatos/farmacologia , Pulpite/microbiologia , Timol/farmacologia , Animais , Candida albicans/efeitos dos fármacos , Linhagem Celular , Creosoto/efeitos adversos , Dano ao DNA , Cárie Dentária/microbiologia , Polpa Dentária/irrigação sanguínea , Combinação de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/microbiologia , Hidrocarbonetos Iodados/efeitos adversos , Hiperemia/microbiologia , Metacrilatos/efeitos adversos , Camundongos , Staphylococcus aureus/efeitos dos fármacos , Timol/efeitos adversos
3.
J Contemp Dent Pract ; 14(3): 483-7, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24171994

RESUMO

BACKGROUND: Autoclave sterilization and microwave sterilization has been suggested as the effective methods for the disinfection of elastomeric impressions, but subjecting elastomeric impressions to extreme temperature may have adverse effects on critical properties of the elastomers. AIM: To evaluate the effect of chemical disinfection as well as autoclave and microwave sterilization on the surface roughness of elastomeric impression materials. MATERIALS AND METHODS: The surface roughness of five commercially available polyvinyl siloxane impression materials (Coltene President, Affinis Perfect impression, Aquasil, 3M ESPE Express and GC Exafast) were evaluated after subjecting them to chemical disinfection, autoclaving and microwave sterilization using a Talysurf Intra 50 instrument. Twenty specimens from each material were fabricated and divided into four equal groups, three experimental and one control (n=25). The differences in the mean surface roughness between the treatment groups were recorded and statistically analyzed. RESULTS: No statistically significant increase in the surface roughness was observed when the specimens were subjected to chemical disinfection and autoclave sterilization, increase in roughness and discoloration was observed in all the materials when specimens were subjected to microwave sterilization. CONCLUSION: Chemical disinfection did not have a significant effect but, since it is less effective, autoclave sterilization can be considered effective and autoclaving did not show any specimen discoloration as in microwave sterilization. Microwave sterilization may be considered when impressions are used to make diagnostic casts. A significant increase in surface roughness may produce rougher casts, resulting in rougher tissue surfaces for denture and cast restorations. CLINICAL SIGNIFICANCE: Autoclave sterilization of vinyl polysiloxane elastomeric impressions for 5 minutes at 134°C at 20 psi may be considered an effective method over chemical disinfection and microwave sterilization, because chemical disinfection does not eliminate all disease-causing microorganisms and microwave sterilization leads to a rougher impression surface.


Assuntos
Desinfetantes de Equipamento Odontológico/química , Materiais para Moldagem Odontológica/química , Desinfecção/métodos , Micro-Ondas/uso terapêutico , Polivinil/química , Siloxanas/química , Esterilização/métodos , Cor , Creosoto/química , Combinação de Medicamentos , Elastômeros/química , Formocresóis/química , Temperatura Alta , Humanos , Hidrocarbonetos Iodados/química , Teste de Materiais , Pressão , Silicones , Propriedades de Superfície , Timol/química , Fatores de Tempo
4.
Arch Environ Contam Toxicol ; 61(3): 368-75, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21222116

RESUMO

Comparative toxicity testing was performed on selected materials that may be used in aquatic construction projects. The tests were conducted on the following materials: (1) untreated wood species (hemlock [Tsuga ssp], Western red cedar (Thuja plicata), red oak [Quercus rubra], Douglas fir [Pseudotsuga menziesii], red pine [Pinus resinosa], and tamarack [Larix ssp]); (2) plastic wood; (3) Ecothermo wood hemlock stakes treated with preservatives (e.g., chromated copper arsenate [CCA], creosote, alkaline copper quaternary [ACQ], zinc naphthenate, copper naphthenate, and Lifetime Wood Treatment); (4) epoxy-coated steel; (5) hot-rolled steel; (6) zinc-coated steel; and (7) concrete. Those materials were used in acute lethality tests with rainbow trout, Daphnia magna, Vibrio fischeri and threespine stickleback. The results indicated the following general ranking of the materials (from the lowest to highest LC(50) values); ACQ > creosote > zinc naphthenate > copper naphthenate > CCA (treated at 22.4 kg/m(3)) > concrete > red pine > western red cedar > red oak > zinc-coated steel > epoxy-coated steel > CCA (6.4 kg/m(3)). Furthermore, the toxicity results indicated that plastic wood, certain untreated wood species (hemlock, tamarack, Douglas fir, and red oak), hot-rolled steel, Ecothermo wood, and wood treated with Lifetime Wood Treatment were generally nontoxic to the test species.


Assuntos
Materiais de Construção/toxicidade , Testes de Toxicidade/métodos , Madeira/química , Aliivibrio fischeri/efeitos dos fármacos , Animais , Arseniatos/análise , Arseniatos/toxicidade , Ácidos Carboxílicos/análise , Ácidos Carboxílicos/toxicidade , Creosoto/análise , Creosoto/toxicidade , Daphnia/efeitos dos fármacos , Monitoramento Ambiental/métodos , Larix/química , Pinus/química , Plásticos/análise , Plásticos/toxicidade , Pseudotsuga/química , Quercus/química , Thuja/química , Tsuga/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
J Hazard Mater ; 418: 126091, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118544

RESUMO

Lignocellulosic biomass represents an unlimited and ubiquitous energy source, which can effectively address current global challenges, including climate change, greenhouse gas emissions, and increased energy demand. However, lignocellulose recalcitrance hinders microbial degradation, especially in case of contaminated materials such as creosote (CRO)-treated wood, which necessitates appropriate processing in order to eliminate pollution. This study might be the first to explore a novel bacterial consortium SST-4, for decomposing birchwood sawdust, capable of concurrently degrading lignocellulose and CRO compounds. Afterwards, SST-4 which stands for molecularly identified bacterial strains Acinetobacter calcoaceticus BSW-11, Shewanella putrefaciens BSW-18, Bacillus cereus BSW-23, and Novosphingobium taihuense BSW-25 was evaluated in terms of biological sawdust pre-treatment, resulting in effective lignocellulose degradation and 100% removal of phenol and naphthalene. Subsequently, the maximum biogas production observed was 18.7 L/kg VS, while cumulative methane production was 162.8 L/kg VS, compared to 88.5 without microbial pre-treatment. The cumulative energy production from AD-I and AD-II through biomethanation was calculated as 3177.1 and 5843.6 KJ/kg, respectively. The pretreatment process exhibited a significant increase in the energy yield by 83.9%. Lastly, effective CRO detoxification was achieved with EC50 values exceeding 90%, showing the potential for an integrated process of effective contaminated wood management and bioenergy production.


Assuntos
Consórcios Microbianos , Sphingomonadaceae , Anaerobiose , Biocombustíveis/análise , Biomassa , Creosoto , Lignina/metabolismo , Metano , Sphingomonadaceae/metabolismo , Madeira/química
6.
Bioresour Technol ; 338: 125521, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273631

RESUMO

This study aims to explore distinct bacterial strains from wood-feeding termites and to construct novel bacterial consortium for improving the methane yield during anaerobic digestion by degrading birchwood sawdust (BSD) and removing creosote (CRO) compounds simultaneously. A novel bacterial consortium CTB-4 which stands for the molecularly identified species Burkholderia sp., Xanthomonas sp., Shewanella sp., and Pseudomonas mosselii was successfully developed. The CTB-4 consortium showed high efficiency in the removal of naphthalene and phenol. It also revealed reduction in lignin, hemicellulose, and cellulose by 19.4, 52.5, and 76.8%, respectively. The main metabolites after the CRO degradation were acetic acid, succinate, pyruvate, and acetaldehyde. Pretreatment of treated BSD mixed with CRO enhanced the total methane yield (162 L/kg VS) by 82.7% and biomass reduction by 54.7% compared to the untreated substrate. CRO showed a toxicity decrease of >90%, suggesting the efficiency of constructed bacterial consortia in bioremediation and biofuel production.


Assuntos
Isópteros , Madeira , Anaerobiose , Animais , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Biocombustíveis/análise , Creosoto , Lignina/metabolismo , Metano , Consórcios Microbianos , Pseudomonas , Madeira/química
7.
Biomolecules ; 11(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34439823

RESUMO

Alveolar osteitis (AO) is a common complication following the extraction of the teeth, particularly the lower third molars. It starts within a few days after the extraction and manifests mainly as pain in the extraction site. Several strategies of treatment are available in order to relieve pain and heal the extraction wound. Recently, a novel medical device combining hyaluronic acid (HA) and octenidine (OCT) was introduced for the treatment of AO. This series of case reports aims to summarize the initial clinical experiences with this new device and to highlight factors possibly interfering with this treatment. The medical documentation of five patients with similar initial situations treated for AO with HA + OCT device was analyzed in detail. Smoking and previous treatment with Alveogyl (Septodont, Saint-Maur-des-Fossés, France) were identified as factors interfering with the AO treatment with the HA + OCT device. In three patients without these risk factors, the treatment led to recovery within two or three days. The patient pretreated with Alveogyl and the smoker required six and seven applications of the HA + OCT device, respectively. According to these initial observations, it seems smoking and previous treatment with Alveogyl prolong the treatment of AO using the HA + OCT device that, in turn, shows a rapid effect if these risk factors are not present.


Assuntos
Alvéolo Seco/tratamento farmacológico , Ácido Hialurônico/uso terapêutico , Iminas/uso terapêutico , Dor/tratamento farmacológico , Piridinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Adolescente , Adulto , Creosoto/efeitos adversos , Combinação de Medicamentos , Alvéolo Seco/etiologia , Alvéolo Seco/fisiopatologia , Alvéolo Seco/cirurgia , Equipamentos e Provisões , Feminino , Humanos , Hidrocarbonetos Iodados/efeitos adversos , Pessoa de Meia-Idade , Dente Molar/cirurgia , Dor/etiologia , Dor/fisiopatologia , Dor/cirurgia , Fatores de Risco , Fumar/efeitos adversos , Timol , Extração Dentária/efeitos adversos , Resultado do Tratamento , Cicatrização/fisiologia
8.
Environ Sci Pollut Res Int ; 26(19): 19598-19605, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31077053

RESUMO

The ability of standard soils to capture heavy metals or polycyclic aromatic hydrocarbons (PAHs) from ammoniacal copper zinc arsenate (ACZA)- or creosote-treated wood, respectively, was assessed using pressure-treated posts immersed in a freshwater pond. The soil, in heat-sealed, permeable plastic mesh sachets, was able to intercept copper, zinc, arsenic, and PAHs migrating from the posts. Chemical levels were much higher immediately adjacent to the posts and declined with distance from the posts. Metals were consistently detected around ACZA-treated posts, while 10 of the 16 EPA priority pollutants were detected in at least one sachet embedded around creosote-treated posts at each sampling point. These results were consistent with traditional sediment sampling methods. The primary advantages of the sachets were their consistency in terms of soil characteristics and the ease with which they could be retrieved from the pond. Further studies are planned to better understand the role of soil characteristics in the sachets on the ability to capture migrating preservatives.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , Madeira/química , Arseniatos/análise , Cobre/análise , Creosoto/análise , Recuperação e Remediação Ambiental/instrumentação , Desenho de Equipamento , Polímeros/química , Zinco/análise
9.
Acta Odontol Latinoam ; 21(2): 169-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19177855

RESUMO

The aim of this study was to evaluate in vitro the duration of the antimicrobial effect of endodontic sealers by means of the Direct Contact Test. The sealers tested were: Endomethasone - Septodont, Endomethasone C-Septodont, Endion-Voco, Diaket-ESPE, Pulp Canal Sealer-SybronEndo, and AH26-Dentsply DeTrey. The endodontopathic microorganisms (MO) confronted were: Staphylococcus aureus (Sa), Candida albicans (Ca), Enterococcus faecalis (Ef), Prevotella intermedia (Pi), Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn). Test specimens of each sealer were prepared and placed on the surface of agar plates that had been inoculated with each MO, and after predetermined periods, transfers were made from the contact area between the test specimen and the cultured agar and from the area that had not been in contact with the test specimens (control). The results were read as presence/absence of microbial growth and analyzed statistically using the Kruskal-Wallis test. It was concluded that the structural features and virulence of endodontopathic microorganisms determine their response to the sealers, independently of the time during which sealers act and the mechanism by which the antiseptic reaches the microorganism, which in this case was by direct contact.


Assuntos
Anti-Infecciosos/farmacologia , Doenças da Polpa Dentária/microbiologia , Materiais Restauradores do Canal Radicular/farmacologia , Bismuto/farmacologia , Candida albicans/efeitos dos fármacos , Contagem de Colônia Microbiana , Creosoto/farmacologia , Dexametasona/farmacologia , Combinação de Medicamentos , Enterococcus faecalis/efeitos dos fármacos , Resinas Epóxi/farmacologia , Formaldeído/farmacologia , Formocresóis/farmacologia , Fusobacterium nucleatum/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/farmacologia , Humanos , Hidrocarbonetos Iodados/farmacologia , Hidrocortisona/farmacologia , Técnicas Microbiológicas , Polivinil/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Prevotella intermedia/efeitos dos fármacos , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Timol/análogos & derivados , Timol/farmacologia , Fatores de Tempo , Titânio/farmacologia , Virulência , Óxido de Zinco/farmacologia
10.
J Endod ; 42(12): 1815-1818, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27776876

RESUMO

INTRODUCTION: Tricalcium silicate cements can be used for pulp capping, pulpotomies, apical barrier formation in teeth with open apices, repair of root perforations, regenerative endodontics, and root canal filling. The aim of this study was to evaluate and compare the discoloration potential of 3 different tricalcium cements using a bovine tooth model. METHODS: Forty bovine anterior teeth have been used for the study. Crowns separated from the roots were randomly divided into 4 groups: the BioAggregate (IBC, Vancouver, Canada) group, the Biodentine (Septodont, Saint Maur des Fosses, France) group, the mineral trioxide aggregate Angelus (Angelus, Londrina, PR, Brazil) group, and the only blood group. Materials have been placed to the standardized cavities on the lingual surfaces of the crowns, and their contact with blood has been provided. The color values of the samples were measured with a digital tooth shade determinator (VITA Easyshade; VITA Zahnfabrik, Bad Sackingen, Germany) before the placement of the materials, after the placement of the materials, in the 24th hour, in the first week, in the first month, in the third month, and in the first year. The mean value of all groups was compared using the Tukey multiple comparison test (α = 0.05). RESULTS: All groups displayed increasing discoloration during a period of the first year. The "only blood group" showed the highest color change values, and it was followed as BioAggregate, mineral trioxide aggregate Angelus, and Biodentine, respectively. Statistically significant differences were found for Biodentine when compared with the only blood and BioAggregate groups (P < .05). CONCLUSIONS: Considering the results of the study, Biodentine is found to have the least discoloration potential among the tested materials.


Assuntos
Compostos de Alumínio/efeitos adversos , Compostos de Cálcio/efeitos adversos , Hidróxido de Cálcio/efeitos adversos , Hidroxiapatitas/efeitos adversos , Óxidos/efeitos adversos , Silicatos/efeitos adversos , Descoloração de Dente/induzido quimicamente , Dente/efeitos dos fármacos , Animais , Bovinos , Creosoto/efeitos adversos , Cimentos Dentários/efeitos adversos , Materiais Dentários/química , Combinação de Medicamentos , Hidrocarbonetos Iodados/efeitos adversos , Incisivo/efeitos dos fármacos , Teste de Materiais , Agentes de Capeamento da Polpa Dentária e Pulpectomia/efeitos adversos , Materiais Restauradores do Canal Radicular/efeitos adversos , Timol/efeitos adversos , Fatores de Tempo , Raiz Dentária/efeitos dos fármacos
11.
J Endod ; 42(12): 1784-1788, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27769676

RESUMO

INTRODUCTION: The aim was to compare the solubility, radiopacity, and setting times of a tricalcium silicate-containing (BioRoot RCS; Septodont, St Maur-des-Fossés, France) and a mineral trioxide aggregate-containing sealer (MTA Fillapex; Angelus, Londrina, Brazil) with an epoxy resin-based sealer (AH Plus; Dentsply DeTrey, Konstanz, Germany). METHODS: Solubility in distilled water, radiopacity, and setting time were evaluated in accordance with ISO 6876:2012. The solubility was also measured after soaking the materials in phosphate-buffered saline buffer (PBS). All data were analyzed using 1-way analysis of variance and the Student-Newman-Keuls test. RESULTS: After immersion for 1 minute in distilled water, BioRoot RCS was significantly less soluble than AH Plus and MTA Fillapex (P < .05). At all other exposure times, AH Plus was significantly less soluble than BioRoot RCS, whereas BioRoot RCS was significantly more soluble than the other 2 sealers (P < .05). All sealers had the same solubility in PBS and distilled water, except for BioRoot RCS after 28 days. At this exposure time, BioRoot RCS was significantly less soluble in PBS than in distilled water and less soluble than MTA Fillapex (P < .05). All BioRoot RCS specimens immersed in PBS had a surface precipitate after 14 and 28 days. The radiopacity of all sealers was greater than 3 mm aluminum with no statistical significant difference between the sealers (P > .05). The final setting time was 324 (±1) minutes for BioRoot RCS and 612 (±4) minutes for AH Plus. The difference was statistically significant (P < .05). MTA Fillapex did not set completely even after 1 week. CONCLUSIONS: The solubility and radiopacity of the sealers were in accordance with ISO 6876:2012. PBS decreased the solubility of BioRoot RCS.


Assuntos
Compostos de Alumínio/química , Compostos de Cálcio/química , Resinas Epóxi/química , Teste de Materiais , Óxidos/química , Materiais Restauradores do Canal Radicular/química , Silicatos/química , Propriedades de Superfície , Compostos de Alumínio/efeitos da radiação , Compostos de Cálcio/efeitos da radiação , Fenômenos Químicos , Creosoto/química , Combinação de Medicamentos , Resinas Epóxi/efeitos da radiação , Hidrocarbonetos Iodados/química , Microscopia Eletrônica de Varredura , Óxidos/efeitos da radiação , Materiais Restauradores do Canal Radicular/efeitos da radiação , Silicatos/efeitos da radiação , Solubilidade , Timol/química , Fatores de Tempo , Água/química , Raios X , Cimento de Óxido de Zinco e Eugenol/química
12.
Water Res ; 39(7): 1388-96, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15862339

RESUMO

Column studies were conducted to assess the suitability of a non-ionic surfactant Tergitol NP-10 (TNP10) for washing pentachlorophenol (PCP) from soil and non-aqueous phase liquids (NAPLs). Flushing of 50 and 200 pore volumes of 5 g/L TNP10 was required to exhaust the surfactant sorption capacity of the soil and soil plus NAPL, respectively. The sorption of surfactant to the soil in the columns was four times greater than the quantity previously observed in batch tests. Flushing with 5 g/L TNP10 removed 71-79% of the 200mg/kg soil-sorbed PCP after 160 pore volumes compared to 0.7-2% PCP removal without surfactant. In columns additionally containing 0.2% and 0.4% PCP-contaminated heavy oil NAPL, the PCP removal efficiency after flushing 200 pore volumes of 5g/L TNP10 was nearly 100%. Therefore, removal of the PCP was more efficient in the NAPL-containing columns, potentially due to competition of the NAPL for PCP sorption sites. Rate-limited desorption of PCP and TNP10 likely occurred.


Assuntos
Pentaclorofenol/isolamento & purificação , Poloxaleno/química , Poluentes do Solo/isolamento & purificação , Tensoativos/química , Gerenciamento de Resíduos/métodos , Adsorção , Creosoto , Solo/análise , Movimentos da Água
13.
Environ Toxicol Chem ; 23(11): 2604-10, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15559274

RESUMO

The bioavailability of polycyclic aromatic hydrocarbons (PAHs) to benthic organisms is complicated by the variety of ways that they are introduced to coastal waters (dissolved, as nonaqueous phase liquids, and tightly bound to soot, coal, tire rubber, and eroded shale). In order to better understand the controlling variables that affect chemical and biological availability of PAHs, a study was conducted in which three deposit-feeding infaunal benthic invertebrate species (Cirriformia grandis, Clymenella torquata, and Macoma balthica) were exposed to sediments amended with PAH-rich materials (coal dust, tire rubber, diesel soot, creosote, crude oil, and fuel oil). Lipid and organic carbon normalized bioaccumulation factors (BAF(1oc)s) were calculated after 20 d of exposure and PAH bioavailability from the different treatments was assessed. Bioaccumulation of coal-derived PAHs usually was too low to be measured, though PAHs associated with soot and tire rubber showed significant accumulation in organism tissues. Polycyclic aromatic hydrocarbons from the fuel oil, creosote, and crude oil treatments were more bioavailable than PAHs bound in solid carbonaceous matrices (soot, coal, and tire rubber). Desorption of PAHs from the amended sediments into seawater also was measured using XAD resin. As was observed with bioaccumulation, PAHs in coal were desorbed the least; tire rubber and diesel soot were intermediate; and creosote, fuel oil, and crude oil desorbed to the greatest extent. In only one out of the three species evaluated was PAH bioaccumulation related to extent of desorption after 20 d. Decoupling between biological and chemical availability may be due to species-specific factors such as surfactant-mediated solubilization in the guts of some deposit-feeding organisms. A significant finding of this work was the demonstration that PAHs associated with soot and tire rubber in their native state (rather than experimentally added) are available to some benthic biota.


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos/química , Moluscos/metabolismo , Poliquetos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Adsorção , Animais , Disponibilidade Biológica , Carbono/química , Creosoto , Poluentes Ambientais/metabolismo , Combustíveis Fósseis , Moluscos/química , Poliquetos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Borracha , Especificidade da Espécie
14.
J Contam Hydrol ; 58(1-2): 147-67, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12236554

RESUMO

Direct pumping and enhanced recovery of coal tar and creosote dense, non-aqueous phase liquids (DNAPLs) from the subsurface have had mixed results because these DNAPLs are viscous fluids that can potentially alter aquifer wettability. To improve the inefficiencies associated with waterflooding, the research presented here considered the use of a polymer solution that can be added to the injected flood solution to increase the viscosity and decrease the velocity of the flooding solution. Results from one-dimensional, vertically oriented laboratory column experiments that evaluate the recovery of coal-derived DNAPL with both water and polymer flooding solutions are presented. The final DNAPL saturation remaining in the column was assessed in water and oil-wet systems for three viscous DNAPLs. Adding polymer to increase the aqueous solution viscosity did not have a significant impact in water-wet systems. A final DNAPL saturation of approximately 19% was achieved for both water and polymer floods. In contrast, the addition of polymer significantly improved recovery in oil-wet systems. The final saturation was over 40% in oil-wet systems after waterflooding, but approximately 19% with a polymer flushing solution. Although the final saturation produced with polymer flooding was similar between the oil- and water-wet systems, differences in the relative permeability and distribution of DNAPL in the porous matrix caused the DNAPL recovery to be much slower in the oil-wet system.


Assuntos
Alcatrão/química , Creosoto/química , Polímeros/química , Poluentes Químicos da Água , Humanos , Solventes/química , Purificação da Água/métodos
15.
Odontostomatol Trop ; 22(88): 9-17, 1999 Dec.
Artigo em Francês | MEDLINE | ID: mdl-11372128

RESUMO

The conventional usage of endo-canalar antiseptic of Rockle's type (SEPTODONT Laboratory) and the application of a standard protocol during two seances have shown: a 68% successful rate of healing at six months post therapeutic follow up, the diameter decrease of radiological images of peri-apical lesions, more than 80% in relative value; for about 20 teeth drawned lots (in a prospective study). This reduction of 33% at least at the maxillary and 50% at the mandible may be a reliable indicator for an endodontic surgical decision or fixed prosthetic rehabilitation report since the third month (especially peri-apical lesions of more than five millimetres of diameter). The respect of the security apical-limit of the root canal filling is fundamental. The second Senegalese (Dakar) serial will permit us to evaluate the use of calcium hydroxide in mediate and prolonged canalar disinfection.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Doenças Periapicais/terapia , Irrigantes do Canal Radicular/uso terapêutico , Tratamento do Canal Radicular , Ápice Dentário/fisiopatologia , Adulto , Creosoto/uso terapêutico , Necrose da Polpa Dentária/terapia , Restauração Dentária Permanente , Combinação de Medicamentos , Feminino , Seguimentos , Formocresóis/uso terapêutico , Guta-Percha/uso terapêutico , Humanos , Hidrocarbonetos Iodados/uso terapêutico , Masculino , Mandíbula , Maxila , Doenças Periapicais/diagnóstico por imagem , Estudos Prospectivos , Radiografia , Materiais Restauradores do Canal Radicular/uso terapêutico , Estatística como Assunto , Timol/uso terapêutico , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/efeitos dos fármacos , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
16.
Aust Dent J ; 58(4): 522-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24320911

RESUMO

Local anaesthesia is used routinely throughout dentistry. Complications are, however, relatively uncommon. A unique case of superficial skin necrosis and neurological symptoms following administration of local anaesthesia for dental treatment is reported and the possible mechanisms behind this unusual presentation are discussed. Awareness of this possible complication and its mechanism helps clinicians diagnose and manage patients with similar problems appropriately.


Assuntos
Anestesia Dentária/efeitos adversos , Creosoto/efeitos adversos , Hidrocarbonetos Iodados/efeitos adversos , Hipestesia/induzido quimicamente , Pele/patologia , Timol/efeitos adversos , Tremor/induzido quimicamente , Anestesia Local , Anestésicos Locais , Combinação de Medicamentos , Feminino , Humanos , Necrose/induzido quimicamente , Adulto Jovem
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