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1.
Int. j. morphol ; 36(2): 395-401, jun. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-954127

RESUMO

We aimed to evaluate the effects of detorsion and Allium sativum (garlic oil) treatment on the ovarian reserve in an ovarian torsion model. Ovarian torsion may lead to loss of ovarian tissue and infertility. It is an experimental rat study that was carried out on 16 sets of ovaries each, one for treatment group and a control group. In the control group, the procedure involved only the surgically opening and closing the abdomen. Bilateral adnexal torsion/detorsion was performed after a 3-hour ischemia period for the detorsion-only group. The detorsion + Allium sativum group received a 5 ml/kg dose of Allium sativum intraperitoneally, 2 hours before surgery. After the second surgery, removed ovarian samples were evaluated for follicle counts, damage scores and other parameters. Primordial, preantral, small antral and large antral follicle counts were significantly higher in the detorsion + Allium sativum group. Degeneration, congestion, hemorrhage ,inflammation and total damage scores were significantly elevated in the detorsion only group compared to those for the detorsion + Allium sativum group. Finally, there was a significant correlation between AMH alterations and postoperative, preantral follicle count (p<0.05). As a conclusion detorsion + Allium sativum treatment may be effective in protecting the ovarian reserve after torsion.


Intentamos evaluar los efectos de la detorsión y el tratamiento con Allium sativum (aceite de ajo) en la reserva ovárica en un modelo de torsión ovárica. La torsión ovárica puede ocasionar pérdida de tejido ovárico e infertilidad. Este es un estudio experimental en ratas que se llevó a cabo en 16 sets de ovarios para cada grupo: tratamiento y control. En el grupo control, el procedimiento involucró solamente la apertura y el cierre quirúrgicos del abdomen. La torsión / detorsión anexial bilateral se realizó después de un período de isquemia de 3 horas para el grupo de solo detorsión. El grupo de detorsión + Allium sativum recibió una dosis de 5 ml / kg de Allium sativum por vía intraperitoneal, 2 horas antes de la cirugía. Después de la segunda cirugía, las muestras ováricas eliminadas se evaluaron para recuentos de folículos, puntajes de daño y otros parámetros. Los recuentos de folículos antrales primordiales, preantrales, antrales pequeños y grandes fueron significativamente mayores en el grupo con detorsión + Allium sativum. Los puntajes de degeneración, congestión, hemorragia, inflamación y daño total fueron significativamente elevados en el grupo de solo detorsión, en comparación con los del grupo de detorsión + Allium sativum. Finalmente, hubo una correlación significativa entre las alteraciones de AMH y el recuento de folículos preantrales postoperatorios (p <0,05). Como conclusión, el tratamiento con detorsión + Allium sativum puede ser eficaz para proteger la reserva ovárica después de la torsión.


Assuntos
Animais , Feminino , Ratos , Doenças Ovarianas/tratamento farmacológico , Ovário/efeitos dos fármacos , Sulfetos/administração & dosagem , Compostos Alílicos/administração & dosagem , Alho/química , Anormalidade Torcional , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras , Modelos Animais de Doenças , Reserva Ovariana/efeitos dos fármacos
3.
Electron. j. biotechnol ; 25: 58-63, ene. 2017. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1008708

RESUMO

Background: Sulphur-oxidizing microorganisms are widely used in the biofiltration of total reduced sulphur compounds (odorous and neurotoxic) produced by industries such as the cellulose and petrochemical industries, which include high-temperature process steps. Some hyperthermophilic microorganisms have the capability to oxidize these compounds at high temperatures (N60°C), and archaea of this group, for example, Sulfolobus metallicus, are commonly used in biofiltration technology. Results: In this study, a hyperthermophilic sulphur-oxidizing strain of archaea was isolated from a hot spring (Chillán, Chile) and designated as M1. It was identified as archaea of the genus Sulfolobus (99% homology with S. solfataricus 16S rDNA). Biofilms of this culture grown on polyethylene rings showed an elemental sulphur oxidation rate of 95.15 ± 15.39 mg S l-1 d-1, higher than the rate exhibited by the biofilm of the sulphur-oxidizing archaea S. metallicus (56.8 ± 10.91 mg l-1 d-1). Conclusions: The results suggest that the culture M1 is useful for the biofiltration of total reduced sulphur gases at high temperatures and for other biotechnological applications.


Assuntos
Sulfetos/metabolismo , Archaea/metabolismo , Biofilmes , Oxirredução , Filogenia , Reação em Cadeia da Polimerase , Sulfolobus , Archaea/isolamento & purificação , Archaea/genética , Polietileno , Fontes Termais/microbiologia , Eletroforese , Filtração , Extremófilos , Temperatura Alta
4.
Acta odontol. latinoam ; 30(1): 13-18, 2017. tab
Artigo em Inglês | LILACS | ID: biblio-907402

RESUMO

This study compared the surface detail reproduction anddimensional accuracy of molds after disinfection using 2% sodium hypochlorite, 2% chlorhexidine digluconate or 0.2% peracetic acid to those of molds that were not disinfected, forfour elastomeric impression materials: polysulfide (Light Bodied Permlastic), polyether (Impregum Soft), polydimethylsiloxane(Oranwash L) and polyvinylsiloxane (Aquasil Ultra LV). Themolds were prepared on a matrix by applying pressure, using aperforated metal tray. The molds were removed followingpolymerization and either disinfected (by soaking in one of thesolutions for 15 minutes) or not disinfected. The samples werethus divided into 16 groups (n=5). Surface detail reproductionand dimensional accuracy were evaluated using opticalmicroscopy to assess the 20 ­µm line over its entire 25 mm length. The dimensional accuracy results (%) were subjectedto analysis of variance (ANOVA) and the means were comparedby Tukey’s test (α=5%). The 20 ­µm line was completelyreproduced by all elastomeric impression materials, regardlessof disinfection procedure. There was no significant difference between the control group and molds disinfected with peraceticacid for the elastomeric materials Impregum Soft (polyether)and Aquasil Ultra LV (polyvinylsiloxane). The high­leveldisinfectant peracetic acid would be the choice material for disinfection.


Este estudo comparou a reprodução de detalhes da superfície e estabilidade dimensional de moldes obtidos após desinfecção utilizando hipoclorito de sódio 2%, digluconato de clorexidina 2%, ou ácido peracético 0,2% a moldes que não foram desinfetados com quatro elastômeros: polissulfeto (Light Bodied Permlastic), polieter (Impregum Soft), silicona reação porcondensação (Oranwash L) e silicona reação por adição (Aquasil Ultra LV). Os moldes foram preparados sobre matriz conten dolinhas de 20, 50 e 75 µm realizado sob pressão com moldeirade metal perfurada. Os moldes foram removidos após a polimerização e desinfetados (utilizando uma das soluções porimersão, armazenados em frascos fechados durante 15 minutos)ou não desinfetados. Assim, as amostras foram divididas em 16grupos (n=5). A reprodução detalhes da superfície e a precisão dimensional foram avaliadas usando microscopia óptica na linha 20 µm com 25 mm de comprimento, de acordo com a norma ISO 4823. Os resultados de precisão dimensional (%) foram submetidos à análise de variância (A NOVA) e as médias comparadas pelo teste de Tukey com 5% de nível de significância. A linha de 20 µm foi completamente reproduzida por todos os elastômeros, independentemente do processo de desinfecção. Não houve diferença estatisticamente significativa entre o grupo controle e moldes desinfetados com acido peracético para os elastômeros Impregum Soft (polieter) e Aquasil Ultra LV (siliconareação por adição). O desinfetante de alto nível ácido peracético seria o material de escolha para a desinfecção.


Assuntos
Humanos , Materiais para Moldagem Odontológica , Modelos Dentários , Desinfetantes de Equipamento Odontológico/química , Propriedades de Superfície , Análise de Variância , Clorexidina/química , Precisão da Medição Dimensional , Ácido Edético/química , Elastômeros/classificação , Microscopia/métodos , Análise Estatística , Siloxanas/classificação , Hipoclorito de Sódio/química , Sulfetos/classificação
5.
São Paulo; s.n; s.n; 2017. 166p p. ilus, tab.
Tese em Português | LILACS | ID: biblio-874966

RESUMO

Neste trabalho promovemos a síntese de sulfóxidos vinílicos ?-substituídos através da reação de acoplamento cruzado de Suzuki-Miyaura. Também foi feita a síntese de sulfóxidos enínicos inéditos, pela adição do nucleófilo no carbono ß-sulfóxido. Esses compostos eram passíveis de serem submetidos a reação de rearranjo de Pummerer aditivo e assim gerarem uma pequena biblioteca de compostos α-tioaldeídos. Um desses aldeídos sintetizados foi empregado na reação de formação de uma imina propargílica, com consequente reação de CuAAC formando iminas triazólicas. Outras iminas arílicas foram sintetizadas, passando por uma etapa de redução, com intuito de se obter a amina livre, para que fosse feita a reação de ciclização com auxílio de um agente eletrofílico. Outra classe de composto organoenxofre foi sintetizada, as N-sulfinil imina, que após a reação de acoplamento cruzado de Sonogashira, com consequente remoção de um grupo protetor e a formação do anel heterocíclico, foram obtidos compostos triazólicos N-sulfinil imínicos.


In this work we promote the synthesis of α-substituted vinylic sulfoxides through the Suzuki-Miyaura cross coupling reaction. Also the synthesis of unpublished enynic sulfoxides was made, by the addition of the nucleophile in the ß-sulfoxide carbon. These compounds were susceptible to additive Pummerer rearragement reaction and thus generated a small library of compounds. One of these aldehydes synthesized was used in the formation reaction of a propargyl imine, with consequent CuAAC reaction, forming triazol imines. Other aryl imines were synthesized, undergoing a reduction step, in order to obtain the free amine, so that the cyclization reaction was carried out with the aid of an electrophilic agent. Another class of organosulfur compound was synthesized, the N-sulfinyl imine, which after the Sonogashira cross-coupling reaction, with consequent removal of a protecting group and formation of the heterocyclic ring, N-sulfinyl imine triazolic compounds were obtained.


Assuntos
Iminas , Sulfetos , Sulfóxidos , Espectroscopia de Ressonância Magnética
6.
Braz. j. microbiol ; 47(4): 846-852, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828191

RESUMO

Abstract Copper mine drainages are restricted environments that have been overlooked as sources of new biocatalysts for bioremediation and organic syntheses. Therefore, this study aimed to determine the enzymatic activities (esterase, epoxide hydrolase and monooxygenase) of 56 heterotrophic bacteria isolated from a neutral copper mine drainage (Sossego Mine, Canaã dos Carajás, Brazil). Hydrolase and monooxygenase activities were detected in 75% and 20% of the evaluated bacteria, respectively. Bacterial strains with good oxidative performance were also evaluated for biotransformation of organic sulfides. Fourteen strains with good enzymatic activity were identified by 16S rRNA gene sequencing, revealing the presence of three genera: Bacillus, Pseudomonas and Stenotrophomonas. The bacterial strains B. megaterium (SO5-4 and SO6-2) and Pseudomonas sp. (SO5-9) efficiently oxidized three different organic sulfides to their corresponding sulfoxides. In conclusion, this study revealed that neutral copper mine drainages are a promising source of biocatalysts for ester hydrolysis and sulfide oxidation/bioremediation. Furthermore, this is a novel biotechnological overview of the heterotrophic bacteria from a copper mine drainage, and this report may support further microbiological monitoring of this type of mine environment.


Assuntos
Bactérias/classificação , Bactérias/enzimologia , Cobre , Microbiologia Ambiental , Oxirredução , Filogenia , Sulfetos/metabolismo , Bactérias/isolamento & purificação , Bactérias/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Enzimas , Esterases/genética , Esterases/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Mineração
7.
Rev. latinoam. enferm ; 22(6): 934-941, 16/12/2014. tab
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-732952

RESUMO

OBJECTIVE: to investigate the burnout syndrome and its relationship with demographic and academic variables among undergraduate nursing students at a public university in Southern Brazil. METHOD: a quantitative study with 168 students, by applying an adaptation of the Maslach Burnout Inventory - Student Survey, validated for this study. We used descriptive and variance analysis of the data analysis. RESULTS: we found that students do not have the burnout syndrome, manifesting high average scores in Emotional Exhaustion, low in Disbelief and high in Professional Effectiveness; that younger students who perform leisure activities have greater Professional Effectiveness, unlike students in early grades with no extracurricular activities; combining work and studies negatively influenced only the Professional Effectiveness factor, while the intention of giving up influenced negatively Disbelief and Professional Effectiveness factors. CONCLUSION: the situations that lead students to Emotional Exhaustion need to be recognized, considering the specificity of their study environments. .


OBJETIVO: investigar a síndrome de Burnout e sua relação com variáveis sociodemográficas e acadêmicas, entre estudantes de graduação em enfermagem de uma universidade pública do Sul do Brasil. MÉTODO: estudo quantitativo, realizado com 168 estudantes, mediante a aplicação de uma adaptação do Maslach Burnout Inventory - Student Survey, validada para este estudo. Utilizou-se a análise descritiva e de variância para análise dos dados. RESULTADOS: constatou-se que os estudantes não apresentam a síndrome de Burnout, manifestando médias altas em exaustão emocional, baixas em descrença e altas em eficácia profissional; que estudantes mais jovens e que realizam atividades de lazer apresentam maior eficácia profissional, diferentemente de estudantes das séries iniciais e que não realizam atividades extracurriculares; conciliar trabalho e estudos influenciou negativamente apenas o fator eficácia profissional, enquanto a intenção de desistir do curso influenciou negativamente os fatores descrença e eficácia profissional. CONCLUSÃO: faz-se necessário o reconhecimento das situações que levam os estudantes à exaustão emocional, considerando a especificidade de seus ambientes de formação. .


OBJETIVO: investigar la síndrome de burnout y su relación con variables sociodemográficas y académicas, entre estudiantes de pregrado en enfermería de una universidad pública del Sur de Brasil. MÉTODO: estudio cuantitativo, desarrollado con 168 estudiantes, mediante la aplicación de una adaptación del Maslach Burnout Inventory - Student Survey, validada para fines de ese estudio. Fueron utilizados los análisis descriptivo y de variancia para analizar los datos. RESULTADOS: se constató que los estudiantes no presentan la síndrome de burnout, manifestando altos promedios en Agotamiento Emocional, bajos en Descreencia y altos en Eficacia Profesional; que estudiantes más jóvenes y que practican actividades de ocio presentan mayor Eficacia Profesional, diferentemente de estudiantes de los años iniciales sin actividades extracurriculares; conciliar trabajo y estudios influyó negativamente apenas el factor Eficacia Profesional, mientras la intención de desistir del curso influyó negativamente los factores Descreencia y Eficacia Profesional. CONCLUSIÓN: es necesario reconocer las situaciones que llevan a los estudiantes al Agotamiento Emocional, considerando la especificidad de sus ambientes de formación. .


Assuntos
Animais , Masculino , Ratos , Cromatografia Líquida de Alta Pressão/métodos , Glucuronatos/análise , Malonatos/metabolismo , Microssomos Hepáticos/análise , Sulfetos/análise , Glucuronatos/metabolismo , Glucuronosiltransferase/metabolismo , Microssomos Hepáticos/metabolismo , Ratos Endogâmicos , Compostos de Sulfidrila/metabolismo , Sulfetos/metabolismo
8.
Electron. j. biotechnol ; 15(3): 7-7, May 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640551

RESUMO

Background: The behaviour of two biotrickling filters connected in serie (BTF) inoculated with Acidithiobacillus thiooxidans and Thiobacillus thioparus, biodegrading hydrogen sulphide (H2S) and dimethyl sulphide (DMS) simultaneously were studied. A model which considers gas to liquid mass transfer and biooxidation in the biofilm attached to the support is developed. Additionally, a fixed bed biotrickling filter where the microorganism is immobilized in a biofilm which degrades a mixture of H2S and DMS is implemented. Validation of the model was carried out using experimental data obtained at different H2S and DMS loads. Results: The inhibitory effect caused by the presence of H2S on the DMS is observed, which is evidenced by the decrease of the DMS removal efficiency from 80 to 27 percent, due to the preference that T. thioparus has by simple metabolism. H2S is not affected by the DMS, with removal efficiencies of 95 to 97 percent, but it decreases at high concentrations of the compound, due to the inhibition of metabolism by high H2S input loads. The model which describes the BFT fits successfully with the experimental results and it has a high sensitivity to inhibition parameters. Conclusion: It is shown that the microorganism has a high affinity for H2S, producing substrate inhibition when the concentration is high. The H2S is able to inhibit the DMS biooxidation, whereas the DMS does not affect the H2S biooxidation.


Assuntos
Filtração , Sulfeto de Hidrogênio , Modelos Teóricos , Sulfetos , Thiobacillus , Acidithiobacillus thiooxidans
9.
Bol. latinoam. Caribe plantas med. aromát ; 10(3): 218-221, mayo 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-687010

RESUMO

Essential oil from leaves and roots of Allium schoenoprasum L. (Alliaceae) were analyzed by GC/MS. The oils extracted by hydrodistillation yielded 0.02 percent and 0.03 percent for leaves and roots, respectively. Five (99.12 percent leaves) and four (98.32 percent roots) components were identified being bis-(2-sulfhydryethyl)-disulfide (72.06 percent leaves, 56.47 percent roots) the major constituent on the two oil samples while 2,4,5-trithiahexane (5.45 percent leaves, 15.90 percent roots) and tris (methylthio)-methane (4.01 percent leaves, 12.81 percent roots) were detected in lower amounts.


Los aceites esenciales de hojas y raíces de Allium schoenoprasum L. (Alliaceae fueron analizados por CG/EM. La extracción por hidrodestilación mostró un rendimiento de 0.02 por ciento y 0.03 por ciento para las hojas y raíces, respectivamente. Cinco (99.12 por ciento hojas) y cuatro (98.32 por ciento raíces) compuestos fueron identificados siendo el bis-(2-sulfidietil)-disulfuro (72.06 por ciento hojas, 56.47 por ciento raíces) el compuesto mayoritario en los dos aceites mientras que 2,4,5-tritiahexano (5.45 por ciento hojas, 15.90 por ciento raíces) y tris (metilthio)-metano (4.01 por ciento hojas, 12.81 por ciento raíces) fueron observados en menores cantidades.


Assuntos
Óleos Voláteis/química , Cebolinha-Francesa/química , Folhas de Planta/química , Sulfetos/análise , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/análise , Metano/análise , Raízes de Plantas/química
11.
Braz. j. med. biol. res ; 43(9): 821-827, Sept. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-556862

RESUMO

Nasopharyngeal carcinoma is a common malignancy in Southern China of uncertain etiologic origin. Diallyl trisulfide (DATS), one of the major components of garlic (Allium sativum), is highly bactericidal and fungicidal. In this study, we investigated the function of p38 mitogen-activated protein kinase (MAPK) and caspase-8 in DATS-induced apoptosis of human CNE2 cells using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], flow cytometry assay, and Western blotting. After CNE2 cells were treated with DATS (50, 100, or 150 μM) for 24 h, cell viability rates were 75.9, 63.4 and 39.6 percent, and apoptosis rates were 24.5, 36.9, and 62.4 percent, respectively. The data showed that DATS induced CNE2 cell death in a dose-dependent manner. After human CNE2 cells were treated with 100 μM DATS and inhibitors (10 μM SB203580 and Z-LETD-FMK for p38MAPK and caspase-8, respectively), changes in cell viability and apoptosis and in p38MAPK and caspase-8 activity were detected. Cell viability rates were 66.5 and 68.1 percent and decreased 9.9 and 11.5 percent compared with inhibitor treatment alone. Apoptosis rates were 31.53 and 29.98 percent and increased 9.1 and 10 percent compared with inhibitor treatment alone. The results indicated that DATS activates p38MAPK and caspase-8, but both inhibitors have an effect on P38MAPK and caspase-8 activity. In conclusion, our data indicate that p38MAPK and caspase-8 are involved in the process of DATS-induced apoptosis in human CNE2 cells and interact with each other.


Assuntos
Humanos , Compostos Alílicos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , /metabolismo , Sulfetos/farmacologia , /metabolismo , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Neoplasias Nasofaríngeas/patologia
12.
Electron. j. biotechnol ; 13(5): 11-12, Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591893

RESUMO

Reduced volatile sulphur compounds generate an impact on the environment, because of the bad smell and its low odour threshold. Compared with the existing physicochemical technologies for their elimination, biotrickling filters are an economically and environmentally sustainable alternative. Usually mixed cultures of microorganisms are used for inoculating biotrickling filters, in this case a pure culture of Thiobacillus thioparus is used for generating a biofilm, allowing to measure its capacity for the oxidation of four volatile reduced sulphur compounds: hydrogen sulphide, dimethyl sulphide, methyl mercaptan and dimethyl disulphide, using a residence time of 0.033 hrs. The viable cells of the biofilm were quantified by epifluorescence microscopy, staining the cells with ethidium bromide and acridine orange, polymerase chain reaction analysis in real time was used for testing the predominance of T. thiopharus in the biofilm. The microorganism was able to adhere and grow on the surface of rings made of polyethylene, with a viable population of 7•10(7) cell•ring-1, a 74 percent of total cells. The real time PCR showed a persistence of the population of T. thioparus for more than 300 days of operation, without being displaced by other microbial species. The maximum elimination capacities for each compound were 34.4; 21.8; 30.8 and 25.6 gS•m-3•h-1 for H2S, dimethylsulphide, dimethyldisulphide and methyl mercaptan, respectively. We conclude that it is possible to implement a biotrickling filter with the bacteria T. thioparus, which can oxidize volatile reduced sulphur compounds efficiently.


Assuntos
Filtração/métodos , Odorantes , Sulfetos/metabolismo , Thiobacillus/metabolismo , Biodegradação Ambiental , Biofilmes , Poluição Ambiental , Microscopia de Fluorescência , Oxirredução , Reação em Cadeia da Polimerase
13.
Neotrop. entomol ; 39(4): 638-644, July-Aug. 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-558854

RESUMO

Tetranychus evansi Baker & Pritchard is an important pest of solanaceous plants, including tomatoes. This mite is characterized by a high reproductive rate, which leads to high population growth in a short period of time causing important economic damage. Control of T. evansi is mainly through synthetic acaricides. In searching for environmentally friendly control measures, we evaluated the efficiency of alternative products to control T. evansi on tomato plants under greenhouse conditions. The products tested were lime sulphur and neem based products. We first estimated the lethal concentration (LC) and instantaneous rate of increase (r i) of T. evansi exposed to different product concentrations in laboratory conditions, and later tested the efficacy of LC95 and the concentrations that restrained mite population growth (r i = 0) in greenhouse conditions. The following treatments were repeated three times: NeemPro (81.0 and 71.6 mg a.i./l), Natuneem (31.1 and 20.4 mg ai/l), Organic Neem (39.1 and 30.4 mg a.i./l), lime sulphur (1.0 and 0.6 percent) and water (control). For all products, control provided by LC95 was higher than provided for lower concentrations (r i = 0) one day after spraying. However, after five days, for both concentrations, the percentage of T. evansi population reduction was superior to 95 percent and increased over time. Only plants sprayed with Natuneem (31.1 mg a.i./l) showed symptoms of phytotoxicity. Lime sulphur and neem based products, applied in appropriate concentrations and formulations, bear out as a viable alternative to control T. evansi on tomato plants.


Assuntos
Animais , Compostos de Cálcio/farmacologia , Glicerídeos/farmacologia , Repelentes de Insetos/farmacologia , Lycopersicon esculentum/parasitologia , Controle de Pragas , Sulfetos/farmacologia , Terpenos/farmacologia , Tetranychidae/efeitos dos fármacos , Tiossulfatos/farmacologia
14.
Braz. j. microbiol ; 41(1): 209-217, Jan.-Mar. 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-531754

RESUMO

Sulfentrazone is amongst the most widely used herbicides for treating the main crops in the State of São Paulo, Brazil, but few studies are available on the biotransformation of this compound in Brazilian soils. Soil samples of Rhodic Hapludox soil were supplemented with sulfentrazone (0.7 µg active ingredient (a.i.) g-1 soil) and maintained at 27ºC. The soil moisture content was corrected to 30, 70 or 100 percent water holding capacity (WHC) and maintained constant until the end of the experimental period. Herbicide-free soil samples were used as controls. Another experiment was carried out using soil samples maintained at a constant moisture content of 70 percent WHC, supplemented or otherwise with the herbicide, and submitted to different temperatures of 15, 30 and 40º C. In both experiments, aliquots were removed after various incubation periods for the quantitative analysis of sulfentrazone residues by gas chromatography. Herbicide-degrading microorganisms were isolated and identified. After 120 days a significant effect on herbicide degradation was observed for the factor of temperature, degradation being higher at 30 and 40º C. A half-life of 91.6 days was estimated at 27º C and 70 percent WHC. The soil moisture content did not significantly affect sulfentrazone degradation and the microorganisms identified as potential sulfentrazone degraders were Nocardia brasiliensis and Penicillium sp. The present study enhanced the prospects for future studies on the bio-prospecting for microbial populations related to the degradation of sulfentrazone, and may also contribute to the development of strategies for the bioremediation of sulfentrazone-polluted soils.


Assuntos
Biodegradação Ambiental , Herbicidas/análise , Herbicidas/isolamento & purificação , Nocardia/isolamento & purificação , Penicillium/isolamento & purificação , Solo , Umidade do Solo , Sulfetos/análise , Cromatografia Gasosa , Métodos , População , Amostragem , Técnicas
15.
Braz. dent. j ; 21(6): 520-527, 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-572298

RESUMO

The aim of this study was to determine quantitatively and qualitatively the inorganic particle fraction of commercially available dental elastomers. The inorganic volumetric fraction of two addition silicones (Reprosil Putty/Fluid and Flexitime Easy Putty/Fluid), three condensation silicones (Clonage Putty/Fluid, Optosil Confort/Xantopren VL and Silon APS Putty/Fluid), one polyether (Impregum Soft Light Body) and one polysulfide (Permlastic Light Body) was accessed by weighing a previously determined mass of each material in water before and after burning samples at 600ºC, during 3 h. Unsettled material samples were soaked in acetone and chloroform for removal of tthe organic portion. The remaining filler particles were sputter-coated with gold evaluation of their morphology and size, under scanning electron microscopy (SEM). Flexitime Easy Putty was the material with the highest results for volumetric particle fraction, while Impregum Soft had the lowest values. Silon 2 APS Fluid presented the lowest mean filler size values, while Clonage Putty had the highest values. SEM micrographs of the inorganic particles showed several morphologies - lathe-cut, spherical, spherical-like, sticks, and sticks mixed to lathe-cut powder. The results of this study revealed differences in particle characteristics among the elastometic materials that could lead to different results when testing mechanical properties.


O objetivo desse estudo foi determinar quantitativamente e qualitativamente a fração de partículas inorgânicas de elastômeros dentais disponíveis comercialmente. A fração volumétrica de dois silicones por adição (Reprosil Denso/Fluído e Flexitime Denso/Fluído), três silicones por condensação (Clonage Denso/Fluído, Optosil/Xantopren, e Silon 2 APS Denso/Fluído), um poliéter (Impregum Soft Light) e um polissulfeto (Permlastic Light Body) foi determinada pela pesagem prévia de uma determinada massa de cada material em água antes e após a queima das amostras a 600ºC, por 3 h. Amostras de material não polimerizado foram imersas em acetona e clorofórmio para a remoção da parte orgânica. As partículas de carga remanescentes foram cobertas com uma camada de ouro para avaliação da sua morfologia e tamanho, em microscopia eletrônica de varredura. O material Flexitime Denso foi o material com maior fração volumétrica de partículas de carga, enquanto que o Impregum teve menor fração volumétrica. Silon 2 APS Fluído apresentou partículas de carga de menor tamanho, enquanto que o Clonage Denso apresentou as maiores partículas. A observação em MEV. mostrou partículas de carga com vários tipos de morfologia (esféricas, irregulares, semi-esféricas, retangulares e mistura de retangulares/irregulares). Os resultados desse estudo mostraram diferenças nas partículas de carga dos materiais, as quais podem levar a diferentes resultados em suas propriedades mecânicas.


Assuntos
Análise do Estresse Dentário , Materiais para Moldagem Odontológica/química , Elastômeros/química , Compostos Inorgânicos/análise , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polivinil , Resinas Sintéticas/química , Espectrometria por Raios X , Siloxanas/química , Sulfetos/química , Viscosidade
16.
West Indian med. j ; 58(5): 407-409, Nov. 2009.
Artigo em Inglês | LILACS | ID: lil-672511

RESUMO

Studies conducted on the secondary metabolite (natural product), dibenzyl trisulphide (DTS), which was isolated from the sub-tropical shrub Petiveria alliacea (guinea hen weed, anamu) [Phytolaccaceae] have shown tremendous pharmaceutical promise as a drug prototype. This is now reflected in the development of the broad spectrum anti-cancer molecule, fluorapacin (bis(4-fluorobenzyl) trisulphide) which has an excellent safety profile. The mode of action elucidated for DTS is the mitogen activated protein extracellular regulated kinases 1 and 2 (MAPKinases ERK 1 and ERK 2). The MAPKinase signal transduction biochemical pathways are important in the regulation of a wide range of cellular processes which are important in disease establishment. These processes include: cancer cell proliferation, nerve repair, memory enhancement, autoimmune diseases, which are linked to thymic cell involution and bone marrow functions, cerebrovascular and cardiovascular diseases. In addition to the MAPkinase signal transduction mode of action, DTS also prevents the denaturation of serum albumin which is a feature of nonsteroidal anti-inflammatory drugs, thus supporting the molecule's possible role in the treatment of inflammatory ageing diseases.


Los estudios realizados sobre el metabolito secundario (producto natural), trisulfuro de dibencilo (TSD), que fue aislado del arbusto subtropical Petiveria alliacea (hierba de guinea, anamú) [Phytolaccaceae] muestran que se trata de una tremenda promesa farmacéutica como prototipo de droga. Esto se refleja actualmente en el desarrollo de la molécula anticancerígena de amplio espectro, la fluorapacina (bis (4-fluorobencilo) trisulfuro) que posee un excelente perfil de seguridad. El modo de acción para el TSD se explica partiendo de las proteínas quinasas 1 y 2 activadas por mitógenos y reguladas por señales extracelulares (Quinasas MAP ERK 1 y ERK 2). Las vías bioquímicas de transducción de la señal de la quinasa MAP, son importantes en la regulación de una amplia variedad de procesos celulares, importantes a la hora de determinar una enfermedad. Dichos procesos comprenden: la proliferación de la célula cancerosa, la reparación de nervios, el mejoramiento de la memoria, y las enfermedades autoinmunes, vinculadas con la involución tímica y las funciones de la médula, las enfermedades cerebrovasculares y cardiovasculares. Además del modo de acción de las transducción de señales de la quinasa MAP, el TSD previene también la desnaturalización de la albúmina sérica, lo cual constituye una característica de las drogas anti-inflamatorias no esferoidales, apoyando así el posible papel de las moléculas en el tratamiento de las enfermedades inflamatorias en el proceso de envejecimiento.


Assuntos
Humanos , Compostos de Benzil/farmacologia , Desenho de Fármacos , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , Fluorbenzenos/farmacologia , Phytolaccaceae , Transdução de Sinais/efeitos dos fármacos , Sulfetos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células-Tronco Mesenquimais/efeitos dos fármacos , Degeneração Neural/tratamento farmacológico , Extratos Vegetais/farmacologia
18.
J. appl. oral sci ; 16(4): 280-285, July-Aug. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-486497

RESUMO

In the present study, two types of tests (tensile strength test and polymerization inhibition test) were performed to evaluate the physical and chemical properties of four impression materials [a polysulfide (Permlastic), a polyether (Impregum), a condensation silicone (Xantopren) and a polyvinylsiloxane (Aquasil) ,3; when polymerized in contact with of one conventional (Hemostop) and two experimental (Vislin and Afrin) gingival retraction solutions. For the tensile strength test, the impression materials were mixed and packed into a steel plate with perforations that had residues of the gingival retraction solutions. After polymerization, the specimens were tested in tensile strength in a universal testing machine. For the polymerization inhibition test, specimens were obtained after taking impressions from a matrix with perforations that contained 1 drop of the gingival retraction solutions. Two independent examiners decided on whether or not impression material remnants remained unpolymerized, indicating interference of the chemical solutions. Based on the analysis of the results of both tests, the following conclusions were reached: 1. The tensile strength of the polysulfide decreased after contact with Hemostop and Afrin. 2. None of the chemical solutions inhibited the polymerization of the polysulfide; 3. The polyether presented lower tensile strength after polymerization in contact with the three gingival retraction agents; 4. The polyether had its polymerization inhibited only by Hemostop; 5. None of the chemical solutions affected the tensile strength of the condensation silicone; 6. Only Hemostop inhibited the polymerization of the condensation silicone; 7. The polyvinylsiloxane specimens polymerized in contact with Hemostop had significantly lower tensile strength; 8. Neither of the chemical solutions (Afrin and Vislin) affected the tensile strength of the polyvinylsiloxane and the condensation silicone; 9. Results of ...


Assuntos
Técnica de Moldagem Odontológica , Materiais para Moldagem Odontológica/química , Análise do Estresse Dentário , Dimetilpolisiloxanos/química , Gengiva/efeitos dos fármacos , Teste de Materiais , Transição de Fase , Polivinil/química , Resinas Sintéticas/química , Elastômeros de Silicone/química , Siloxanas/química , Soluções/química , Soluções/farmacologia , Sulfetos/química , Resistência à Tração
19.
Braz. oral res ; 22(4): 293-298, 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-502195

RESUMO

Several impression materials are available in the Brazilian marketplace to be used in oral rehabilitation. The aim of this study was to compare the accuracy of different impression materials used for fixed partial dentures following the manufacturers' instructions. A master model representing a partially edentulous mandibular right hemi-arch segment whose teeth were prepared to receive full crowns was used. Custom trays were prepared with auto-polymerizing acrylic resin and impressions were performed with a dental surveyor, standardizing the path of insertion and removal of the tray. Alginate and elastomeric materials were used and stone casts were obtained after the impressions. For the silicones, impression techniques were also compared. To determine the impression materials' accuracy, digital photographs of the master model and of the stone casts were taken and the discrepancies between them were measured. The data were subjected to analysis of variance and Duncan's complementary test. Polyether and addition silicone following the single-phase technique were statistically different from alginate, condensation silicone and addition silicone following the double-mix technique (p < .05), presenting smaller discrepancies. However, condensation silicone was similar (p > .05) to alginate and addition silicone following the double-mix technique, but different from polysulfide. The results led to the conclusion that different impression materials and techniques influenced the stone casts' accuracy in a way that polyether, polysulfide and addition silicone following the single-phase technique were more accurate than the other materials.


Assuntos
Técnica de Fundição Odontológica/instrumentação , Materiais para Moldagem Odontológica/normas , Técnica de Moldagem Odontológica/instrumentação , Modelos Dentários/normas , Prótese Parcial Fixa/normas , Silicones/normas , Análise de Variância , Teste de Materiais , Sulfetos/normas
20.
Braz. j. microbiol ; 38(3): 430-434, July-Sept. 2007. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-464766

RESUMO

Sulindac sulfide is a non-steroidal anti-inflammatory drug (NSAID) with chemopreventive effect on human cancer cells. Due to the involvement of the somatic recombination in the carcinogenic process, sulindac sulfide's recombinogenic potential was evaluated by the Homozygotization Index (HI) in the filamentous fungus Aspergillus nidulans. The drug's recombinogenic potential was evaluated by its capacity to induce homozygosis of recessive genes from heterozygous diploid cells. Sulindac sulfide at 175 and 350 æM concentrations induced mitotic recombination in A. nidulans diploid cells, with HI values for genetic markers higher than 2.0, and significantly different from control HI values. The recombinogenic effect of NSAID was related to the induction of DNA strand breaks and cell cycle alterations. Sulindac sulfide's carcinogenic potential was also discussed.


Sulfeto de sulindaco é um antiinflamatório não-esteroidal com efeitos quimiopreventivos em cânceres humanos. O presente estudo teve como objetivo avaliar o potencial recombinagênico do sulfeto de sulindaco em células diplóides de Aspergillus nidulans. O efeito recombinagênico da droga foi demonstrado através da homozigotização de genes recessivos, previamente presentes em heterozigose. Os valores de HI (índice de Homozigotização) para diferentes marcadores genéticos apresentaram-se maiores do que 2,0 e significativamente diferentes dos valores obtidos em sulfeto de sulindaco ausência da droga (controle). O potencial recombinagênico do sulfeto de sulindaco foi associado à indução de quebras na molécula do DNA e a alterações no ciclo celular. O potencial carcinogênico do sulfeto de sulindaco foi discutido no presente trabalho.


Assuntos
Humanos , Anti-Inflamatórios , Aspergillus nidulans , Homozigoto , Técnicas In Vitro , Recombinação Genética , Sulfetos , Sulindaco , Marcadores Genéticos , Métodos , Amostragem
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