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1.
Hig. aliment ; 33(288/289): 1171-1176, abr.-maio 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1482122

RESUMO

O objetivo deste trabalho foi analisar a estabilidade física e físico-química de silagens com diferentes concentrações de ácido acético e ácido sulfúrico, proferida com resíduos de Brachyplatystoma rousseauxii (Castelnau, 1855) (dourada). O método consistiu da adição de 0,5% de ácido sulfúrico; 3 e 5% de ácido acético (silos diferentes) em resíduos de Dourada. Durante a estocagem foram mensurados os parâmetros: pH, temperatura, umidade, cinzas e lipídios. Os tratamentos demonstraram poucas variações entre si, mantendo-se próximos ao do produto in natura, exceto para os níveis de umidade que apresentaram padrões decrescentes. Contudo, o silo contendo maior concentração de inoculante foi o que apresentou silagem com melhor estabilidade.


Assuntos
Animais , Peixes-Gato , Resíduos de Alimentos , Silagem/análise , Ácido Acético/administração & dosagem , Ácidos Sulfúricos/administração & dosagem , Fenômenos Químicos
2.
Journal of Cancer Prevention ; : 139-145, 2019.
Artigo em Inglês | WPRIM | ID: wpr-764315

RESUMO

Based on epidemiological studies, an International Agency for Research on Cancer Working Group determined that strong inorganic acid mists containing sulfuric acid are carcinogenic to human even though, sulfuric acid, per se, is not. Accumulative studies indicate that there is a link between chronic occupational exposure to sulfuric acid mists and an increased risk of laryngeal cancer. Unintended, acute exposure to sulfuric acid mists can cause corrosive damage to target tissues depending on the route of exposure. This review compares the toxicity and carcinogenicity of sulfuric acid mists compared to other strong inorganic acid mists. It also examines the routes and duration of exposure (short-term, prolonged, and long-term). In vivo evidence does not support or refute the carcinogenicity of sulfuric inorganic mists even though its co-carcinogenic or promoting potential has been considered. On the basis of existing evidence on sulfuric acid mist toxicity, we suggested a putative adverse outcome pathway (AOP) relevant to carcinogenicity caused by mists containing sulfuric acid. A possible key factor involved in sulfuric acid mist carcinogenesis is the genotoxic effects of low pH since it can increase instability in chromosomes and DNA. A putative AOP for sulfuric acid mist carcinogenicity would help generate better risk assessments and more accurate predictions regarding the risk of developing cancer due to prolonged exposure. Establishing an AOP would also be useful for future studies examining the carcinogenicity of other strong inorganic mists.


Assuntos
Humanos , Carcinogênese , Vazamento de Resíduos Químicos , DNA , Estudos Epidemiológicos , Concentração de Íons de Hidrogênio , Agências Internacionais , Neoplasias Laríngeas , Exposição Ocupacional , Medição de Risco , Enxofre , Ácidos Sulfúricos
3.
Chinese Journal of Hematology ; (12): 1003-1007, 2019.
Artigo em Chinês | WPRIM | ID: wpr-1012115

RESUMO

Objective: To explore the effects and molecular mechanism of the selective JAK1inhibitor SHR0302 and Ruxolitinib on myeloproliterative neoplasms (MPN) cell line SET2 and primary cells in vitro. Methods: Cell proliferation was detected by CCK8 kit. Colony forming experiment was conducted to evaluate erythroid burst colony formation unit (BFU-E) of primary cells from MPN patients. Multi-factor kits were used to detect six inflammatory cytokines. Phosphorylated proteins of Jak-Stat signaling pathway were tested by Western blot. Results: At different time points after treated with SHR0302 and Ruxolitinib, the inhibition of cell proliferation was dose dependent by both drugs (P<0.01) . The inhibitory rates of 2.5 μmol/L SHR0302 and 0.1 μmol/L Ruxolitinib on SET2 cells for 72 h were comparable, i.e. (59.94±0.60) % and (64.00±0.66) %, respectively, suggesting that the inhibitory effect of SHR0302 was weaker than that of Ruxolitinib. Similarly, both SHR0302 and Ruxolitinib inhibited BFU-E in primary marrow cells from MPN patients in a dose-dependent manner. SHR0302 1.0 μmol/L produced similar degree of inhibition compared to Ruxolitinib 0.2 μmol/L. Except IL-12, the expression of other 5 cytokines (IL-6, TNF-α, IL-1β, IL-2, IL-8) was significantly inhibited by 1.6 μmol/L SHR0302 in SET2 cells at 24 h (P<0.01) , while Ruxolitinib 1.0 μmol/L had the same effect. Several phosphorylated molecules of Jak-Stat signaling pathway were significantly inhibited by SHR0302 in SET2 cells only for 3 h. P-stat1 (Tyr701) , p-stat3 (Tyr705) were down-regulated when treated with SHR0302 1.0 μmol/L (P<0.05) , p-jak1 (tyr1022/1023) and p-stat5 (Tyr694) were inhibited at 5.0 μmol/L (P<0.05) . Ruxolitinib significantly inhibited the downstream STAT protein at 0.1 μmol/L. Again, the inhibitory effect of SHR0302 on protein expression was weaker than that of Ruxolitinib. Conclusion: SHR0302 can effectively inhibit the proliferation of MPN cell line and patients' primary cells, as well as the expression of inflammatory factors. The molecular mechanism is possibly related to the down-regulation of phosphorylated proteins of Jak-Stat signaling pathway. Overall, the anti-proliferative and anti-inflammatory effects of SHR0302 are weaker than those of Ruxolitinib.


Assuntos
Humanos , Anti-Inflamatórios , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Histona-Lisina N-Metiltransferase , Janus Quinase 1 , Nitrilas , Pirazóis , Pirimidinas , Ácidos Sulfúricos
4.
Acta sci., Biol. sci ; 39(4): 423-430, Oct. - Dec. 2017. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-878455

RESUMO

The seaweeds are bio-resource rich in sulfated and neutral polysaccharides. The tropical seaweed species used in this study (Solieria filiformis), after dried, shows 65.8% (w/w) carbohydrate, 9.6% (w/w) protein, 1.7% (w/w) lipid, 7.0% (w/w) moisture and 15.9% (w/w) ash. The dried seaweed was easily hydrolyzed under mild conditions (0.5 M sulfuric acid, 20 min.), generating fermentable monosaccharides with a maximum hydrolysis efficiency of 63.21%. Galactose and glucose present in the hydrolyzed were simultaneously fermented by Saccharomyces cerevisiae when the yeast was acclimated to galactose and cultivated in broth containing only galactose. The kinetic parameters of the fermentation of the seaweed hydrolyzed were Y(P/S) = 0.48 ± 0.02 g.g−1, PP = 0.27 ± 0.04 g.L−1.h−1, η = 94.1%, representing a 41% increase in bioethanol productivity. Therefore, S. filiformis was a promising renewable resource of polysaccharides easily hydrolyzed, generating a broth rich in fermentable monosaccharides for ethanol production.


As algas marinhas são recursos naturais ricos em polissacarídeos sulfatados e neutros. A espécie de macroalga tropical utilizada neste estudo (Solieria filiformis) apresentou teores de carboidratos de 65,8% (m/m), proteínas de 9,6% (m/m), lipídios de 1,7% (m/m), umidade de 7,0% (m/m) e 15,9 % (m/m) de cinzas. A macroalga seca foi facilmente hidrolisada em condições brandas, na presença de ácido sulfúrico 0,5 M, por 20 min, produzindo monossacarídeos fermentáveis com uma eficiência de hidrólise máxima de 63,21%. A galactose e a glicose presentes no hidrolisado foram fermentadas simultaneamente por Saccharomyces cerevisiae, após aclimatação da levedura cultivada em meio contendo apenas galactose como fonte de carbono. Os parâmetros cinéticos da fermentação do hidrolisado algáceo pela levedura aclimatada a galactose foram Y(P/S) = 0,48 ± 0,02 g.g-1, PP = 0,27 ± 0,04 g.L- 1.h-1, η = 94,1%. Portanto, a macroalga S. filiformis se mostrou um recurso renovável promissor como fonte de polissacarídeos facilmente hidrolisados, gerando um meio nutritivo rico em glucose e galactose para a produção de etanol.


Assuntos
Carragenina , Celulose , Fermentação , Galactose , Alga Marinha , Ácidos Sulfúricos
5.
Rev. Asoc. Odontol. Argent ; 104(2): 79-85, jun. 2016. ilus
Artigo em Espanhol | LILACS | ID: lil-790193

RESUMO

Objetivo: mostrar el efecto de un nuevo procedimiento de descontaminación del biofilm sobre los abscesos periodontales agudos y la periimplantitis. Casos clínicos: un absceso periodontal agudo y una periimplantitis fueron tratados mediante un material de descontaminación de los tejidos bucales. Este consiste en un concentrado acuoso con una mezcla de ácidos hidroxibencensulfónicos e hidroxymetho-xybencénicos y ácido sulfúrico, que se coloca en las bolsas periodontales y alrededor de los implantes. En ninguno de los casos se utilizaron antibióticos locales ni sistémicos. Todos los casos tratados cicatrizaron rápidamente, sin complicaciones. Los pacientes sintieron una leve molestia durante la aplicación del material, que desapareció completamente en pocos segundos. Conclusión: el procedimiento de desecación del biofilm parecería ser una técnica promisoria para el tratamiento de los abscesos periodontales agudos ylas periimplantitis, con la ventaja adicional de que se evita el uso de antibióticos locales y sistémicos.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Abscesso Periodontal/tratamento farmacológico , Biofilmes , Descontaminação/métodos , Peri-Implantite/tratamento farmacológico , Administração Tópica , Ácidos Sulfônicos/uso terapêutico , Ácidos Sulfúricos/uso terapêutico , Bolsa Periodontal/tratamento farmacológico , Hidroxibenzoatos/uso terapêutico
6.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 499-507, 2016.
Artigo em Inglês | WPRIM | ID: wpr-812597

RESUMO

The aim of the study was to investigate the effects of Siwu decoction on hyperuricemia, kidney inflammation, and dysfunction in hyperuricemic mice. Siwu decoction at 363.8, 727.5, and 1 455 mg·kg(-1) was orally administered to potassium oxonate-induced hyperuricemic mice for 7 days. Serum urate, creatinine, and blood urea nitrogen levels and hepatic xanthine oxidase (XOD) activity were measured. The protein levels of hepatic XOD and renal urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), organic anion transporters 1 (OAT1), ATP-binding cassette subfamily G member 2 (ABCG2), organic cation transporter 1 (OCT1), OCT2, organic cation/carnitine transporter 1 (OCTN1), OCNT2, Nod-like receptor family, pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), Caspase-1, and interleukin-1β (IL-1β) were determined by Western blotting. Renal histopathology change was obtained following hematoxylin-eosin staining. Our results indicated that Siwu decoction significantly reduced serum urate, creatinine and blood urea nitrogen levels and increased fractional excretion of uric acid in hyperuricemic mice. It effectively reduced hepatic XOD activity and protein levels in this animal model. Furthermore, Siwu decoction down-regulated URAT1 and GLUT9 protein levels, and up-regulated the protein levels of OAT1, ABCG2, OCT1, OCT2, OCTN1, and OCTN2 in the kidney of the hyperuricemic mice. Additionally, Siwu decoction remarkably reduced renal protein levels of NLRP3, ASC, Caspase-1, and IL-1β in the hyperuricemic mice. These results suggested that Siwu decoction exhibited anti-hyperuricemic and anti-inflammatory effects by inhibiting hepatic XOD activity, regulating renal organic ion transporter expression, and suppressing renal NLRP3 inflammasome activation, providing the evidence for its use in the treatment of hyperuricemia and associated kidney inflammation.


Assuntos
Animais , Humanos , Masculino , Camundongos , Nitrogênio da Ureia Sanguínea , Creatinina , Urina , Medicamentos de Ervas Chinesas , Hiperuricemia , Tratamento Farmacológico , Alergia e Imunologia , Urina , Interleucina-1beta , Genética , Alergia e Imunologia , Rim , Alergia e Imunologia , Fígado , Proteína 1 Transportadora de Ânions Orgânicos , Genética , Alergia e Imunologia , Ácidos Sulfúricos , Ácido Úrico , Urina
7.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 774-776, 2014.
Artigo em Chinês | WPRIM | ID: wpr-289798

RESUMO

<p><b>OBJECTIVE</b>To establish a method for determination of a variety of acid gas in the workplace air by Ion Chromatography. (hydrofluoric acid, hydrogen chloride or hydrochloric acid, sulfur anhydride or sulfuric acid, phosphoric acid, oxalic acid).</p><p><b>METHOD</b>The sample in workplace air was collected by the porous glass plate absorption tube containing 5 ml leacheate. (Sulfuric acid fog, phosphoric acid aerosol microporous membrane after collection, eluted with 5 ml of eluent.) To separated by AS14+AG14 chromatography column, by carbonate (2.0+1.0) mmol/L (Na(2)CO(3)-NaHCO(3)) as eluent, flow rate of 1 ml/min, then analyzed by electrical conductivity detector. The retain time was used for qualitative and the peak area was used for quantitation.</p><p><b>RESULTS</b>The each ion of a variety of acid gas in the air of workplace were excellent in carbonate eluent separation. The linear range of working curve of 0∼20 mg/L. The correlation coefficient r>0.999; lower detection limit of 3.6∼115 µg/L; quantitative limit of 0.012∼0.53 mg/L; acquisition of 15L air were measured, the minimum detection concentration is 0.004 0∼0.13 mg/m(3). The recovery rate is 99.7%∼101.1%. In the sample without mutual interference ions. Samples stored at room temperature for 7 days.</p><p><b>CONCLUSION</b>The same analysis method, the detection of various acidic gases in the air of workplace, simple operation, good separation effect, high sensitivity, high detection efficiency, easy popularization and application.</p>


Assuntos
Ácidos não Carboxílicos , Ar , Poluentes Ocupacionais do Ar , Cromatografia , Métodos , Gases , Ácido Clorídrico , Ácido Fluorídrico , Íons , Limite de Detecção , Ácidos Fosfóricos , Ácidos Sulfúricos , Local de Trabalho
8.
China Journal of Chinese Materia Medica ; (24): 2774-2776, 2014.
Artigo em Chinês | WPRIM | ID: wpr-299856

RESUMO

Study a method for the detemination of the content of polysaccharides in Gentiana farreri, and analysis of the content of polysaccharides from different producing areas. The results showed that using the anthrone-sulfuric acid method, simple operation, accurate result. Sample was measured at 620 nm absorbance after anthrone-sulfuric acid color, at this wavelength, solution absorption and glucose showed a good linear relationship; The linearity was in the range of 0.01-0.07 g x L(-1) (r = 0.996 7). The recovery rate was 99.41%, with RSD of 2.0%. Considering the experimental conditions, to determine the solid-liquid ratio 1:60, extracting time 50 min, concentration of ethanol 80%. The mass fraction of polysaccharides was the highest to reached 0.743% in G. farreri from Gansu Xiahe. This experiment has laid a good foundation for further study on G. farreri.


Assuntos
Antracenos , Química , Técnicas de Química Analítica , Métodos , Gentiana , Química , Geografia , Modelos Lineares , Polissacarídeos , Reprodutibilidade dos Testes , Ácidos Sulfúricos , Química , Fatores de Tempo
9.
Pakistan Journal of Pharmaceutical Sciences. 2013; 26 (5): 977-984
em Inglês | IMEMR | ID: emr-138419

RESUMO

Voltammetric analysis at platinum and gold rotating disc electrode [RDE] in 0.1 mol 1[-1] sulphuric acid has been applied for the determination of the active ingredient in solid dosage form. Non zero intercept in the limiting current versus concentration plot was proportionally good to excellent for the solid dosage form and is free from interference from adsorption on the electrodes. All of the dosage forms proved amenable to rapid voltammetric determination with a means standard deviation of 1.2


Assuntos
Platina , Ouro , Tecnologia Farmacêutica/instrumentação , Ácidos Sulfúricos/química , Preparações Farmacêuticas/análise , Desenho de Equipamento , Formas de Dosagem , Técnicas Eletroquímicas
10.
Korean Journal of Legal Medicine ; : 216-219, 2013.
Artigo em Coreano | WPRIM | ID: wpr-93098

RESUMO

Sulfuric acid can cause local or systemic effects after exposure by inhalation, ingestion, or topical application. Direct ingestion is the main exposure route for fatal sulfuric acid injury. Fatal accidents involving the inhalation of toxic sulfuric acid vapors are rare. Inhalation of sulfuric acid fumes causes severe irritation or corrosive damage to the upper respiratory tract. Consequently, severe congestion, edema, and inflammation of the mucous membranes of the upper respiratory passages hinder the entry of air into the lungs, possibly leading to fatalities in victims. A 35-year-old man died at his home after complaining of a severe sore throat. One day earlier, he had worked in a sulfuric acid tank in a copper-smelting plant while wearing an ordinary gas mask that offered no protection against sulfurous acid vapors. Upon autopsy, the larynx and epiglottis showed pronounced edema, congestion, and inflammation that histologically mimicked an acute bacterial suppurative inflammation, accompanied by severe pulmonary edema. A field analysis of the air inside the sulfuric acid tank revealed SO4(2-) positivity and a 40% sulfuric acid concentration.


Assuntos
Adulto , Humanos , Autopsia , Ingestão de Alimentos , Edema , Epiglote , Estrogênios Conjugados (USP) , Inflamação , Inalação , Laringe , Pulmão , Mucosa , Faringite , Plantas , Edema Pulmonar , Dispositivos de Proteção Respiratória , Sistema Respiratório , Enxofre , Ácidos Sulfúricos
11.
Braz. dent. j ; 22(3): 179-184, 2011. ilus
Artigo em Inglês | LILACS | ID: lil-595640

RESUMO

The bone-biomaterial interface has been characterized by layers of afibrillar extracellular matrix (ECM) enriched in non collagenous proteins, including osteopontin (OPN), a multifunctional protein that in bone controls cell adhesion and ECM mineralization. Physical and chemical aspects of biomaterial surfaces have been demonstrated to affect cell-ECM-substrate interactions. The present paper described the ability of oxidative nanopatterning of titanium (Ti) surfaces to control extracellular OPN deposition in vitro. Ti discs were chemically treated by a mixture of H2SO4/H2O2 for either 30 min [Nano(30') Ti] or 4 h [Nano(4h) Ti]. Non-etched Ti discs were used as control. Primary osteogenic cells derived from newborn rat calvarial bone were plated on control and etched Ti and grown under osteogenic conditions up to 7 days. High resolution scanning electron microscopy revealed that treated Ti discs exhibited a nanoporous surface and that areas of larger nanopits were noticed only for Nano(4h) Ti. Large extracellular OPN accumulation were detectable only for Nano(4h) Ti, which was associated with OPN-positive cells with typical aspects of migrating cells. At day 3, quantitative results in terms of areas of OPN labeling were as follows: Nano(4h) Ti > Nano(30') Ti > Control Ti. In conclusion, chemically nanostructured Ti surfaces may support the enhancement of endogenous extracellular OPN deposition by osteogenic cells in vitro depending on the etching time, a finding that should be taken into consideration in strategies to biofunctionalize implant surfaces with molecules with cell adhesion capacity.


A interface osso-implante é caracterizada pela presença de uma camada de matriz extracellular (MEC) afibrilar rica em proteínas não-colágenas, incluindo osteopontina (OPN), cujas funções no tecido ósseo estão relacionadas à adesão celular e ao controle do processo de mineralização da MEC (crescimento de cristais). Aspectos físicos e químicos das superfícies de biomateriais podem afetar as interações célula-MEC-substrato. O objetivo do presente estudo foi demonstrar a capacidade de aspectos nanotopográficos de superfície de titânio (Ti) de controlar a deposição extracelular de OPN in vitro. Discos de Ti foram tratados quimicamente por solução de H2SO4/H2O2 durante 30 min [Nano(30') Ti] ou 4 h [Nano(4h) Ti]. Superfícies de Ti não tratadas foram usadas como controle. Células osteogênicas primárias derivadas de calvárias de ratos recém-nascidos foram plaqueadas sobre os discos de Ti e cultivadas em condições osteogênicas por até 7 dias. Microscopia eletrônica de varredura de alta resolução revelou que os discos de Ti tratados quimicamente exibiam superfície nanoporosa, com áreas de nanoporos maiores para Nano(4h) Ti. Apenas para esse grupo detectavam-se acúmulos extensos de OPN extracelular, os quais se distribuíam em áreas adjacentes a células OPN-positivas, com aspectos morfológicos típicos de células em migração. Em conclusão, a nanoestruturação química de superfície de Ti pode favorecer o aumento da deposição extracelular de OPN endógena por células osteogênicas in vitro, dependendo do tempo de condicionamento utilizado, o que deve ser considerado no desenvolvimento de estratégias para funcionalizar superfícies de implantes com moléculas com reconhecido efeito no processo de adesão celular.


Assuntos
Animais , Ratos , Materiais Biocompatíveis/química , Materiais Dentários/química , Proteínas da Matriz Extracelular/farmacocinética , Nanopartículas/química , Osteopontina/farmacocinética , Titânio/química , Adsorção , Animais Recém-Nascidos , Condicionamento Ácido do Dente/métodos , Células Cultivadas , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Peróxido de Hidrogênio/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanotecnologia , Oxirredução , Osteoblastos/metabolismo , Osteoblastos/fisiologia , Osteogênese/fisiologia , Ratos Wistar , Propriedades de Superfície , Ácidos Sulfúricos/química , Fatores de Tempo
12.
Epidemiology and Health ; : e2011006-2011.
Artigo em Inglês | WPRIM | ID: wpr-721308

RESUMO

OBJECTIVES: To propose an alternative procedure, based on a Bayesian network (BN), for estimation and prediction, and to discuss its usefulness for taking into account the hierarchical relationships among covariates. METHODS: The procedure is illustrated by modeling the risk of diarrhea infection for 2,740 children aged 0 to 59 months in Cameroon. We compare the procedure with a standard logistic regression and with a model based on multi-level logistic regression. RESULTS: The standard logistic regression approach is inadequate, or at least incomplete, in that it does not attempt to account for potentially causal relationships between risk factors. The multi-level logistic regression does model the hierarchical structure, but does so in a piecewise manner; the resulting estimates and interpretations differ from those of the BN approach proposed here. An advantage of the BN approach is that it enables one to determine the probability that a risk factor (and/or the outcome) is in any specific state, given the states of the others. The currently available approaches can only predict the outcome (disease), given the states of the covariates. CONCLUSION: A major advantage of BNs is that they can deal with more complex interrelationships between variables whereas competing approaches deal at best only with hierarchical ones. We propose that BN be considered as well as a worthwhile method for summarizing the data in epidemiological studies whose aim is understanding the determinants of diseases and quantifying their effects.


Assuntos
Idoso , Criança , Humanos , Camarões , Diarreia , Estudos Epidemiológicos , Imidazóis , Modelos Logísticos , Naftalenos , Nitrocompostos , Fatores de Risco , Ácidos Sulfúricos
13.
Safety and Health at Work ; : 39-51, 2011.
Artigo em Inglês | WPRIM | ID: wpr-169140

RESUMO

OBJECTIVES: This study was designed to evaluate exposure levels of various chemicals used in wafer fabrication product lines in the semiconductor industry where work-related leukemia has occurred. METHODS: The research focused on 9 representative wafer fabrication bays among a total of 25 bays in a semiconductor product line. We monitored the chemical substances categorized as human carcinogens with respect to leukemia as well as harmful chemicals used in the bays and substances with hematologic and reproductive toxicities to evaluate the overall health effect for semiconductor industry workers. With respect to monitoring, active and passive sampling techniques were introduced. Eight-hour long-term and 15-minute short-term sampling was conducted for the area as well as on personal samples. RESULTS: The results of the measurements for each substance showed that benzene, toluene, xylene, n-butyl acetate, 2-methoxyethanol, 2-heptanone, ethylene glycol, sulfuric acid, and phosphoric acid were non-detectable (ND) in all samples. Arsine was either "ND" or it existed only in trace form in the bay air. The maximum exposure concentration of fluorides was approximately 0.17% of the Korea occupational exposure limits, with hydrofluoric acid at about 0.2%, hydrochloric acid 0.06%, nitric acid 0.05%, isopropyl alcohol 0.4%, and phosphine at about 2%. The maximum exposure concentration of propylene glycol monomethyl ether acetate (PGMEA) was 0.0870 ppm, representing only 0.1% or less than the American Industrial Hygiene Association recommended standard (100 ppm). CONCLUSION: Benzene, a known human carcinogen for leukemia, and arsine, a hematologic toxin, were not detected in wafer fabrication sites in this study. Among reproductive toxic substances, n-butyl acetate was not detected, but fluorides and PGMEA existed in small amounts in the air. This investigation was focused on the air-borne chemical concentrations only in regular working conditions. Unconditional exposures during spills and/or maintenance tasks and by-product chemicals were not included. Supplementary studies might be required.


Assuntos
Humanos , 2-Propanol , Arsenicais , Baías , Benzeno , Carcinógenos , Éter , Etilenoglicol , Etilenoglicóis , Etilenos , Fluoretos , Ácido Clorídrico , Ácido Fluorídrico , Cetonas , Coreia (Geográfico) , Leucemia , Ácido Nítrico , Exposição Ocupacional , Saúde Ocupacional , Fosfinas , Ácidos Fosfóricos , Propilenoglicol , Propilenoglicóis , Semicondutores , Enxofre , Ácidos Sulfúricos , Tolueno , Xilenos
14.
Korean Journal of Nosocomial Infection Control ; : 13-17, 2011.
Artigo em Coreano | WPRIM | ID: wpr-76153

RESUMO

BACKGROUND: Clostridium difficile infection (CDI) is the predominant cause of hospital-acquired diarrhea. This study evaluated the sporicidal activities of several disinfectants against C. difficile spores. METHODS: We used toxigenic C. difficile strains with different ribotypes for our study. We compared the sporicidal activities of Cavicide (Metrex Research Corporation, USA), Cidex OPA (Advanced Sterilization Products, USA), 1% Rely+On Virkon (Dupont, UK), 0.25% Surfanios (Laboratoires Anios, France), sodium hypochlorite (Yuhan Clorox, Korea), and 70% ethyl alcohol (Duksan, Korea) by using dilution-neutralization method. The sporicidal activity of the disinfecting agents was considered to be the inactivation factor (IF). The IF was calculated as the log10 colony forming unit (CFU) reduction of the viable count from the initial inoculums. Disinfectants were considered to be sporicidal if they showed an IF> or =4. RESULTS: Cavicide, 70% ethyl alcohol, Rely+On Virkon, and Surfanios showed no reduction in spore counts at all exposure time. Solutions of sodium hypochlorite diluted 1:100 (> or =400 ppm available chlorine), 1:50, and 1:20 were sporicidal after 5 min, 2 min, and 30 s, respectively. Cidex OPA showed sporicidal activity after 30 min. CONCLUSION: To prevent the transmission of CDI, at least 1,000 ppm sodium hypochlorite solution should be used to disinfect the hospital environment. Contaminated endoscopes should be disinfected with Cidex OPA for more than 30 min.


Assuntos
Clorofenóis , Clostridium , Clostridioides difficile , Contagem de Colônia Microbiana , Diarreia , Desinfetantes , Endoscópios , Etanol , Glutaral , Peróxidos , Ribotipagem , Hipoclorito de Sódio , Esporos , Células-Tronco , Esterilização , Ácidos Sulfúricos
15.
Artigo em Inglês | IMSEAR | ID: sea-134642

RESUMO

Deaths from exposure to caustic substances are infrequently reported in the Forensic Medicine literature. A case of death due to Sulphuric acid ingestion in a patient of Major Depressive Disorder is being reported. This patient was planned for Electro-convulsive therapy, prior to the procedure he had been to bathroom. And when planned to prepare for the procedure on the ECT table, his mouth has smell of pungent odour. This made the psychiatrist to withhold the procedure and subjected him for observation. Later he complained of severe chest pain and restlessness, for which he has been shifted to emergency ward with possible precautions taken before shifting. He was provisionally diagnosed of acid ingestion but there was no history either from patient or from his relatives, as patient has consumed in the bathroom just before the Electro convulsive therapy. Diagnosis was confirmed only after autopsy report. The legal issues concerning suicide in mentally ill patient, autopsy findings, forensic issues and Patho-physiology concerning death by acid ingestion have been discussed.


Assuntos
Adolescente , Autopsia , Transtorno Depressivo Maior , Humanos , Masculino , Suicídio/diagnóstico , Suicídio/etiologia , Suicídio/mortalidade , Ácidos Sulfúricos
16.
Rev. bras. plantas med ; 12(2): 188-194, abr.-jun. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-578953

RESUMO

Ziziphus joazeiro Mart. é uma arvore brasileira endêmica da Caatinga e tem diversos usos no Nordeste. As sementes apresentam dormência tegumentar e o presente trabalho teve por objetivo avaliar tratamentos pré-germinativos com ácido sulfúrico concentrado para superar a dormência. O delineamento experimental utilizado foi o inteiramente casualizado, com 9 tratamentos, sendo 0, 30, 60, 90, 120, 150, 180, 210 e 240 minutos de imersão em ácido sulfúrico concentrado P.A. com três repetições de 50 sementes, em dois experimentos. No experimento 1 foram usadas sementes recém coletadas e a avaliação foi feita durante 140 dias. No experimento 2 foram usadas sementes armazenadas por 5 meses e a avaliação feita durante 100 dias. Ziziphus joazeiro apresenta dormência imposta pelo endocarpo que envolve as sementes, e é necessário o uso de ácido sulfúrico durante 180 minutos para sementes recém-coletadas e por 240 ou 270 minutos, para sementes armazenadas por 5 meses para se atingir 80 por cento de emergência. O tempo de armazenamento das sementes pode influenciar a resposta germinativa, com emergência mais rápida após o armazenamento por 5 meses.


Ziziphus joazeiro Mart. is a Brazilian tree endemic to Caatinga and has been largely used in the Northeast of Brazil. Its seeds present tegument dormancy and this work aimed to evaluate pre-germinative treatments with concentrated sulfuric acid to break dormancy. Experimental design was completely randomized, with 9 treatments, i.e. 0, 30, 60, 90, 120, 150, 180, 210, and 240 min of immersion in concentrated sulfuric acid A.R. with three replicates of 50 seeds, in two experiments. In experiment 1, newly collected seeds were evaluated for 140 days. In experiment 2, 5-month stored seeds were evaluated for 100 days. Ziziphus joazeiro presents dormancy imposed by the endocarp that involves the seeds, and sulfuric acid should be used for 180 min on newly collected seeds and for 240 or 270 min on 5-month stored seeds in order to reach 80 percent emergence. Seed storage time may influence the germinative response, with faster emergence after 5-month storage.


Assuntos
Germinação , Epiderme Vegetal , Fenômenos Químicos/métodos , Ácidos Sulfúricos , Tratamento Térmico/métodos , Ziziphus/embriologia , Etnobotânica , Sementes/crescimento & desenvolvimento
17.
Electron. j. biotechnol ; 13(3): 10-11, May 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-577105

RESUMO

Tons of sugar cane bagasse are produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production. Diluted acid hydrolysis is one of the most efficient pretreatments for hemicellulosic solubilization. The hydrolysate obtained is rich in xylose, which can be converted to ethanol by Pichia stipitis. This work used a statistical approach and the severity factor to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid:liquid ratio and time of exposure) on various response variables (xylose concentration, hydrolysis yield, inhibitor concentration and hydrolysate fermentability). The severity factor had a strong influence on the generation of inhibitors. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An acid concentration of 1.09 percent (vv), an S:L ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for the generation of hydrolysates with high xylose concentration and low contents of inhibitors. In such conditions, hydrolysate with 50 g/l of xylose was obtained.


Assuntos
Celulose , Etanol , Hidrólise , Saccharum , Xilose , Ácidos Sulfúricos/análise , Fermentação , Interpretação Estatística de Dados , Fatores de Tempo
18.
Rev. bras. plantas med ; 12(1): 1-7, jan.-mar. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-578927

RESUMO

O objetivo deste trabalho foi determinar o tempo ótimo de escarificação das sementes de Senna alata em ácido sulfúrico e verificar o efeito da temperatura, em condição de luz e escuro, na germinação de sementes dessa espécie. As sementes foram imersas em ácido sulfúrico concentrado por períodos de 0, 15, 30 e 60 minutos, e o teste de germinação realizado em BOD a 25ºC, utilizando quatro repetições de 50 sementes em cada período de tempo, sendo o delineamento estatístico inteiramente casualizado com 4 tratamentos. No segundo experimento, para verificar o efeito da temperatura e da condição de luz mais adequada a germinação, utilizou-se temperaturas de 10 a 45ºC, com intervalos de 5ºC, em condição de luz fluorescente branca ou escuro contínuo (gerbox preto). Utilizou-se o delineamento experimental inteiramente casualizado, disposto em esquema fatorial 8x2, com 4 repetições, de 50 sementes cada. Em todos os testes as avaliações da porcentagem e índice de velocidade de germinação foram feitas diariamente, durante 10 dias, onde as sementes foram consideradas germinadas quando apresentaram 2 mm de raiz. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5 por cento de probabilidade. A escarificação do tegumento com ácido sulfúrico durante 60 minutos, foi ideal para as sementes de Senna alata, por proporcionar maiores valores na porcentagem e velocidade de germinação. A germinação ocorre entre 15 e 40ºC, sendo consideradas fotoblásticas neutras entre 20 e 40ºC e fotoblásticas negativas preferenciais a 15ºC. O melhor desempenho germinativo foi obtido nas temperaturas de 25, 30 e 35ºC, onde ocorreram maior porcentagem e velocidade de germinação.


The aim of this study was to establish the optimum scarification time for Senna alata seeds in sulfuric acid, as well as to verify the effect of temperature on seed germination for this species under conditions of light and darkness. Seeds were immersed in concentrated sulfuric acid for periods of 0, 15, 30 and 60 minutes, and the germination test was carried out in a BOD chamber at 25ºC, using four replicates of 50 seeds for each time period. Experimental design was completely randomized with 4 treatments. In the second experiment, temperatures from 10 to 45ºC, with 5ºC intervals, were used under conditions of fluorescent white light or continuous darkness (black "gerbox") in order to verify the temperature effect and the most suitable light condition for germination. Experimental design was completely randomized, in an 8x2 factorial arrangement, with 4 replicates of 50 seeds each. In all tests, germination percentage and speed index were daily evaluated for 10 days. Seeds were considered germinated when the radicle length was 2 mm. Data were subjected to analysis of variance and means were compared by Tukey's test at 5 percent significance. The tegument scarification with sulfuric acid for 60 minutes was optimal for Senna alata seeds since it led to higher values of germination percentage and speed. Germination occurs between 15 and 40ºC, and seeds are considered neutral photoblastic between 20 and 40ºC and negative photoblastic especially at 15ºC. The best germination performance was observed at 25, 30 and 35ºC, at which germination percentage and speed were higher.


Assuntos
Germinação , Temperatura Alta , Estimulação Luminosa , Sementes/crescimento & desenvolvimento , /crescimento & desenvolvimento , Fenômenos Químicos/métodos , Medição da Velocidade de Vazão/métodos , Reações Químicas/análise , Ácidos Sulfúricos
19.
Braz. dent. j ; 21(1): 3-11, Jan. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-552348

RESUMO

The aims of this study were to characterize the microstructure of a commercially pure titanium (cpTi) surface etched with HCl/H2SO4 (AE-cpTi) and to investigate its in vitro cytocompatibility compared to turned cpTi (T-cpTi). T-cpTi showed a grooved surface and AE-cpTi revealed a surface characterized by the presence of micropits. Surface parameters indicated that the AE-cpTi surface is more isotropic and present a greater area compared to T-cpTi. The oxide film thickness was similar between both surfaces; however, AE-cpTi presented more Ti and O and less C. Osteoblastic cell proliferation, alkaline phosphatase activity, and bone-like nodule formation were greater on T-cpTi than on AE-cpTi. These results show that acid etching treatment produced a surface with different topographical and chemical features compared to the turned one, and such surface modification affected negatively the in vitro cytocompatibility of cpTi as demonstrated by decreasing culture growth and expression of osteoblastic phenotype.


O objetivo deste estudo foi caracterizar a microestrutura de uma superfície de titânio comercialmente puro (cpTi) condicionada com HCl/H2SO4 (acid etched) (AE-cpTi) e investigar sua citocompatibilidade in vitro, comparada à do cpTi usinado (turned) (T-cpTi). O T-cpTi apresentou uma superfície com sulcos e o AE-cpTi exibiu uma superfície caracterizada pela presença de micro-vales. Os parâmetros de superfície indicaram que a superfície AE-cpTi é mais isotrópica e apresenta uma área maior quando comparada à superfície T-cpTi. A espessura da camada de óxido foi similar para as duas superfícies; no entanto, a AE-cpTi apresentou maiores quantidades de Ti e O e menor, de C. A proliferação de células osteoblásticas, a atividade de fosfatase alcalina e a formação de matriz mineralizada foram maiores na superfície T-cpTi que na AE-cpTi. Esses resultados mostram que o condicionamento ácido produziu uma superfície com características topográficas e químicas diferentes quando comparadas às da superfície usinada. Além disso, observou-se que essas modificações de superfície afetaram de forma negativa a citocompatibilidade in vitro do cpTi como demonstrado pela inibição da proliferação celular e da expressão do fenótipo osteoblástico.


Assuntos
Humanos , Condicionamento Ácido do Dente , Materiais Biocompatíveis/farmacologia , Materiais Dentários/farmacologia , Osteoblastos/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/análise , Processo Alveolar/citologia , Materiais Biocompatíveis/química , Biomarcadores/análise , Células Cultivadas , Carbono/química , Adesão Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Materiais Dentários/química , Ácido Clorídrico/química , Interferometria , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese/efeitos dos fármacos , Fenótipo , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Ácidos Sulfúricos/química , Titânio/química
20.
Korean Journal of Gastrointestinal Endoscopy ; : 214-218, 2010.
Artigo em Coreano | WPRIM | ID: wpr-229050

RESUMO

Patients with corrosive esophageal strictures have a high risk of developing carcinoma of the esophagus. For this reason, it is often recommended that resection of the esophagus should be considered for chronic caustic strictures in order to prevent the development of carcinoma. A 49-year-old woman who had undergone an esophagogastrectomy due to esophageal caustic stricture at the age of 23 was admitted with a 2-month history of dysphagia. Esophagoscopy showed a benign postoperative stricture in the remnant esophagus. After endoscopic balloon dilation of the stricture, which was about 5 cm in length, an ulcerative mass was noted distal to the stricture. This mass was diagnosed as squamous cell carcionoma. Nearly all the patients with corrosive carcinomas in the published literature had consumed an alkali drink, but our patient had a history of sulfuric acid ingestion.


Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , Álcalis , Constrição Patológica , Transtornos de Deglutição , Ingestão de Alimentos , Estenose Esofágica , Esofagoscopia , Esôfago , Enxofre , Ácidos Sulfúricos , Úlcera
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