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1.
Oral Dis ; 23(1): 91-96, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27588367

RESUMO

PURPOSE: We aimed to identify a combined prognostic factor for predicting better performance in risk stratification. MATERIALS AND METHODS: We reviewed the clinical and pathological variables of 316 patients with oral squamous cell carcinoma (OSCC) who underwent surgery. To identify a combined predictor, principal component analysis (PCA) was performed. RESULTS: Univariate analysis showed that the independent prognostic variables for overall survival (OS) were pathologic T stage (T1 vs T4, HR = 1.99, 95% CI: = 1.083-3.675, P = 0.026) and pathologic N stage (N0 vs N2, HR=1.90, 95% CI: = 1.17-3.08, P = 0.008). In the multivariate analysis, only pathologic T stage was significant (P = 0.006 and P = 0.007); however, the multivariate model was not significant (P = 0.191). The multivariate model became significant by including lymph node ratio (LNR) instead of pathologic N stage (P = 0.0025 in numeric LNR, P = 0.0007 in categorized LNR). Also, the performance of prediction model was improved by a combined prognostic factor (P = 0.0002). CONCLUSIONS: The newly identified combined prognostic factor included resection margin, differentiation, and LNR, and they were insignificant factors independently except for LNR. This combined prognostic factor showed a good performance although it did not include molecular markers; therefore, it may be used conveniently for risk stratification of patients with OSCC by combining only clinical information.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Bucais/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Estadiamento de Neoplasias , Análise de Componente Principal , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Análise de Sobrevida , Adulto Jovem
2.
Br Poult Sci ; 53(1): 116-24, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22404812

RESUMO

1. An experiment was conducted to evaluate the effect of dietary zinc proteinate (ZP) supplementation on growth performance and on skin and meat quality of male and female broiler chicks. 2. A total of 240 1-d-old male and 240 1-d-old female broiler chicks were randomly distributed into 24 floor pens (12 replicate pens/sex; 20 birds/pen) and were given either 0 (Control diet) or 40 mg/kg ZP (ZP 40), resulting in a 2 × 2 factorial arrangement of treatments. 3. The growth performance of male and female broiler chicks was not affected by the ZP supplementation, but the males showed significantly higher growth performance than did females. 4. ZP supplementation increased the total thickness of skin in both sexes, and males had thicker skin than females. It also increased the collagen content of skin, but not that of meat. Males had higher skin collagen contents than did females, but no sex difference was found in the meat collagen contents. 5. ZP supplementation did not affect the shear force values of skin and meat; however, males had higher shear force values of back skin than females. ZP supplementation increased the zinc contents of thigh meat and plasma in both sexes. Males had higher zinc contents in back skin than females. 6. It is concluded that dietary ZP supplementation could increase the skin quality of broiler chicks in both sexes, particularly in female broilers, without any effect on growth performance. Male broilers have better growth performance and skin quality than females.


Assuntos
Carne/análise , Carne/normas , Proteínas/farmacologia , Pele/química , Zinco/farmacologia , Ração Animal , Animais , Galinhas , Colágeno/química , Dieta/veterinária , Suplementos Nutricionais , Digestão , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Análise de Alimentos , Masculino , Proteínas/administração & dosagem , Aumento de Peso , Zinco/administração & dosagem
3.
Br Poult Sci ; 52(5): 606-12, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22029788

RESUMO

Zinc is an essential trace element. The objective of this research was to investigate the effects of various levels of organic zinc (OZ) supplementation on growth performance and carcase quality of female broiler chickens. A total of 3200 1-d-old female broiler chicks were randomly allotted to 16 floor pens with 200 birds per pen. A maize-wheat-soyabean meal basal diet (Control) was formulated and 20 mg/kg OZ (20 OZ), 40 mg/kg OZ (40 OZ), and 80 mg/kg OZ (80 OZ) were added to the basal diet to form 4 dietary treatments with 4 replicates per treatment. The OZ source was zinc proteinate which contained 15% zinc. Results showed no significant difference between the treatments in growth performance. A significant increase in thigh skin epidermis and dermis thickness was shown in the OZ supplementation groups; however, no effect was found on the thickness of back skin epidermis and dermis. Collagen contents in breast and thigh meats were not influenced by OZ supplementation but a significant increase in collagen content was found in the back and thigh skin. This increase in collagen content was significantly greater in the back and thigh skin of OZ 80 than with OZ 20. Shear force value and zinc concentration in skins and meat were not significantly influenced by supplementation with OZ. It is concluded that dietary OZ does not improve growth performance of broilers; however, it could increase skin thickness by increasing collagen content in skin, thereby improving carcase quality.


Assuntos
Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Carne/normas , Zinco/administração & dosagem , Ração Animal , Animais , Composição Corporal , Colágeno/análise , Dieta/veterinária , Feminino , Pele/química
4.
J Environ Qual ; 39(1): 375-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20048325

RESUMO

To prevent the 7 to 11 million metric tons of waste foundry sand (WFS) produced annually in the USA from entering landfills, current research is focused on the reuse of WFSs as soil amendments. The effects of different WFS-containing amendments on turfgrass growth and nutrient content were tested by planting perennial ryegrass (Lolium perenne L.) and tall fescue (Schedonorus phoenix (Scop.) Holub) in different blends containing WFS. Blends of WFS were created with compost or acid-washed sand (AWS) at varying percent by volume with WFS or by amendment with gypsum (9.6 g gypsum kg(-1) WFS). Measurements of soil strength, shoot and root dry weight, plant surface coverage, and micronutrients (Al, Fe, Mn, Cu, Zn, B, Na) and macronutrients (N, P, K, S, Ca, Mg) were performed for each blend and compared with pure WFS and with a commercial potting media control. Results showed that strength was not a factor for any of the parameters studied, but the K/Na base saturation ratio of WFS:compost mixes was highly correlated with total shoot dry weight for perennial ryegrass (r = 0.995) and tall fescue (r = 0.94). This was further substantiated because total shoot dry weight was also correlated with shoot K/Na concentration of perennial ryegrass (r = 0.99) and tall fescue (r = 0.95). A compost blend containing 40% WFS was determined to be the optimal amendment for the reuse of WFS because it incorporated the greatest possible amount of WFS without major reduction in turfgrass growth.


Assuntos
Sulfato de Cálcio/química , Resíduos Industriais/efeitos adversos , Poa/efeitos dos fármacos , Eliminação de Resíduos/métodos , Dióxido de Silício/química , Solo/análise , Monitoramento Ambiental , Metalurgia , Raízes de Plantas , Brotos de Planta , Poa/crescimento & desenvolvimento , Poluentes do Solo/efeitos adversos , Poluentes do Solo/química
5.
Poult Sci ; 88(11): 2435-41, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19834097

RESUMO

To investigate the effects of irradiation on structural and functional properties of egg white proteins, which enhance foaming ability, egg white was separated and irradiated at doses of 0, 2.5, and 5 kGy. The foaming ability of egg white was increased, whereas foam stability was decreased by irradiation. Turbidity and protein oxidation of egg white was increased by irradiation with an increase of irradiation dose. The content of free sulfhydryl and disulfide was not affected by irradiation. According to 2-dimensional electrophoresis analysis, it was demonstrated that protein scissions are the main changes caused by irradiation and this protein modification may be the main reason for the improvement in foaming ability of egg white.


Assuntos
Proteínas do Ovo/química , Ovos/efeitos da radiação , Irradiação de Alimentos , Animais , Galinhas , Oxirredução , Propriedades de Superfície
6.
J Environ Qual ; 37(6): 2332-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18948487

RESUMO

To avoid increasing costs of landfill disposal, it has become increasingly important for U.S. foundries to identify beneficial reuses for the 8 to 12 million tons of waste foundry sand (WFS) generated annually. A major drawback to the reuse of some WFSs as a soil amendment is their high soil strength, under dry conditions, where root growth may be limited. Fifteen WFSs were analyzed for strength to rupture using lab-formed clods, exchangeable cations (Na, Mg, Ca), metal oxide concentration (Fe, Mn, Al, Si), cation exchange capacity (CEC), and % clay. Several WFS samples from gray iron foundries demonstrated high strength to rupture values (> 1.5 MPa), and could potentially restrict root growth in amended soils. The percentage of Na-bentonite exhibited a positive correlation (R(2) = 0.84) with strength to rupture values. When WFSs containing more Na-bentonite were saturated with 1 mol L(-1) Ca ions, strength values decreased by approximately 70%. Waste foundry sands containing less Na-bentonite were saturated with 1 mol L(-1) Na ions and exhibited a threefold increase in strength. Additions of gypsum (up to 9.6 g kg(-1) sand) to high strength waste foundry sands also caused decreases in strength. These results indicate that high strength WFSs have properties similar to hardsetting soils which are caused by high Na(+) clay content and can be ameliorated by the addition of Ca(2+).


Assuntos
Conservação dos Recursos Naturais/métodos , Resíduos Industriais , Dióxido de Silício , Solo/análise , Microscopia Eletrônica de Varredura , Eliminação de Resíduos/métodos , Estados Unidos
7.
Poult Sci ; 87(11): 2382-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931191

RESUMO

This study was performed to evaluate the antioxidative potential and quality of the breast meat of broiler chickens fed a dietary medicinal herb extract mix (MHEM, consisting of mulberry leaf, Japanese honeysuckle, and goldthread at a ratio of 48.5:48.5:3.0). A total of 480 one-day-old male Cobb broiler chicks were randomly allotted to 12 pens, with 40 birds per pen (replicate), and reared for 35 d. Dietary treatments consisted of a corn-soybean meal basal diet (control); a basal diet with 0.3% MHEM (T1); and a basal diet with 1% (T2) MHEM. At the end of the feeding trial, breast meat samples were excised and stored in a refrigerator at 4 degrees C to be analyzed at d 0, 3, and 7. The MHEM did not affect proximate composition of the breast meat. Total phenols content of the breast meats in the T1 and T2 diets was approximately 2 times greater than that of the control diet (P < 0.05). 1,1-Diphenyl-2-picrylhy-drazyl radical-scavenging activity and 2,2-azinobis-(3 ethylbenzothiazoline-6-sulfonic acid) cation-reduction activity were greater in the T2 diet at d 0 and in the T1 diet at d 3 compared with the control diet (P < 0.05). 2-Thiobarbituric acid-reactive substance values in the T1 and T2 diets were lower than in the control diet at d 3 and 7 and did not increase during storage, whereas the value in the control diet increased significantly. The pH of the T1 diet was significantly greater than that of the control diet at d 0 and 3. In a sensory test, panelists preferred the T1 breast meat throughout the 7-d storage period. This research indicates that dietary MHEM could increase the antioxidative potential and overall preference of breast meat during cold storage.


Assuntos
Ração Animal , Antioxidantes/análise , Carne/análise , Extratos Vegetais/administração & dosagem , Plantas Medicinais , Animais , Antioxidantes/farmacologia , Galinhas , Culinária , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Concentração de Íons de Hidrogênio , Masculino , Morus , Músculo Esquelético , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Aves Domésticas , Paladar , Substâncias Reativas com Ácido Tiobarbitúrico/análise
8.
Environ Technol ; 29(3): 325-32, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18610794

RESUMO

Multi-stage ethanol washing on dioxins-polluted soil and sediment were performed. The results indicated the existence of limit washing concentration (LWC), where no more dioxins were removed from the soil or the sediment by further washing. In each stage, dioxins concentration in the soil, sediment and ethanol could be described satisfactory by the Freundlich equation. The Freundlich capacity factor, K(ef) correlated with the LWC which was estimated to be ca. 1000 pmol g(-1) in the case of soil, and about 150 pmol g(-1) in the case of sediment. Organic contents in the soil and sediment affected the Freundlich intensity parameter, n(-1) but not K(f). A model, which enables the calculation of removal efficiency of PCDD/DFs at each stage using K(f), n, and initial PCDD/DFs concentration, is presented.


Assuntos
Dioxinas/isolamento & purificação , Etanol/química , Poluentes do Solo/isolamento & purificação , Adsorção
9.
Nanotechnology ; 19(18): 185301, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21825687

RESUMO

Enhanced light extraction from a GaN-based power chip (PC) of green light-emitting diodes (LEDs) with a rough p-GaN surface using nanoimprint lithography is presented. At a driving current of 350 mA and with a chip size of 1 mm × 1 mm packaged on transistor outline (TO)-cans, the light output power of the green PC LEDs with nano-rough p-GaN surface is enhanced by 48% when compared with the same device without a rough p-GaN surface. In addition, by examining the radiation patterns, the green PC LED with nano-rough p-GaN surface shows stronger light extraction with a wider view angle. These results offer promising potential to enhance the light output powers of commercial light-emitting devices by using the technique of nanoimprint lithography under suitable nanopattern design.

10.
J Cell Mol Med ; 12(5A): 1593-604, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18053093

RESUMO

Epidermal growth factor (EGF) is synthesized in the pancreas and diabetic animals have low levels of EGF. However, the role of EGF in regulating the major function of the pancreas, insulin secretion, has not been studied. Here, we show that EGF rapidly increased insulin secretion in mouse pancreatic islets, as well as in a pancreatic beta-cell line. These events were dependent on a Ca(2+) influx and phospholipase D (PLD) activity, particularly PLD2, as determined using pharmacological blockers and molecular manipulations such as over-expression and siRNA of PLD isozymes. In addition, EGF also increased plasma insulin levels and mediated glucose lowering in normal and diabetic mice. Here, for the first time, we provide evidence that EGF is a novel secretagogue that regulates plasma glucose levels and a candidate for the development of therapeutics for diabetes.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Insulina/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Fator de Crescimento Epidérmico/sangue , Insulina/sangue , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfolipase D/metabolismo
11.
Poult Sci ; 84(7): 1015-21, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16050118

RESUMO

An experiment was conducted with 240, 1-d-old, male broilers to investigate the effects of Saccharomyces cerevisiae (SC) cell components on the growth performance, meat quality, and ileal mucosa development. There were 4 dietary treatments, each consisting of 6 replicates. Whole yeast (WY), SC extract (YE), and SC cell wall (CW) were added at 0.5, 0.3, and 0.3%, respectively, to the control starter and finisher diets. From 0 to 3 wk of age, a lower feed/gain ratio (P < or = 0.05) was observed with CW, whereas the WY-fed birds at 4 to 5 wk of age showed a lower feed/gain ratio compared with the control. From 0 to 5 wk of age, WY and CW gave higher BW gains than did the control. The shear force of raw drumstick decreased in the WY treatment relative to the control, and YE and CW treatments were intermediate. The shear forces in cooked breast and drumstick in treatments WY and YE decreased when compared with the control. The amount of 2-thiobarbituric acid-reactive substances (TBARS) in the breast meats of WY, YE, and CW were lower than the control at 10 d of incubation. In raw drumstick meats, TBARS values were lower in treatments WY and YE than that of the control at 6 and 10 d of incubation. At 10 d of incubation, skins from YE and CW treatments had lower TBARS values than did the control. Villus height was greater in WY and CW compared with those in control and YE. No differences were found in crypt depth among the 4 treatments. The villus height/ crypt depth ratios in WY and CW were greater than those of the control and YE. It could be concluded that dietary yeast components, such as WY or CW supplementation improved growth performance. Meat tenderness could be improved by the WY or YE. Both YE and CW had oxidation-reducing effects. Yeast cell wall may improve ileal villus development.


Assuntos
Galinhas/crescimento & desenvolvimento , Mucosa Intestinal/crescimento & desenvolvimento , Carne , Probióticos , Saccharomyces cerevisiae , Animais , Dieta , Tecnologia de Alimentos , Íleo/crescimento & desenvolvimento , Masculino , Carne/análise , Pele/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise
12.
Water Sci Technol ; 45(12): 175-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12201100

RESUMO

We cultivated hundreds of sediment, soil, and manure samples taken from rivers and farms in a medium containing ethynylestradiol (EE2) as the sole source of carbon, so that microorganisms in the samples would acclimatize to the presence of EE2. Finally, we isolated an EE2-degrading microorganism, designated as strain HNS-1, from a cowshed sample. Based on its partial nucleotide sequence (563 bp) of the 28S rRNA gene, strain HNS-1 was identified as Fusarium proliferatum. Over 15 days, F. proliferatum strain HNS-1 removed 97% of EE2 at an initial concentration of 25 mg.L-1, with a first-order rate constant of 0.6 d-1. Unknown products of EE2 degradation, which may be more polar compounds that have a phenolic group, remained in the culture medium.


Assuntos
Congêneres do Estradiol/metabolismo , Etinilestradiol/metabolismo , Fusarium/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Agricultura , Animais , Animais Domésticos , Biodegradação Ambiental , Reatores Biológicos , Fusarium/fisiologia , Sedimentos Geológicos/microbiologia , Cinética , Esterco/microbiologia , Microbiologia do Solo
13.
Theriogenology ; 57(7): 1819-28, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12041686

RESUMO

We conducted this study to examine whether serum starvation in culture contributes to better development of bovine reconstructed oocytes and to evaluate which serum-starved somatic cell is the most effective for cloned calf production. In Experiment 1, donor cells of four different types (cumulus cells, ear fibroblasts, oviduct cells and uterine cells) were either serum-starved or not before fusion with enucleated oocytes, and reconstructed oocytes were further cultured for 168 h. Regardless of serum starvation, cumulus cells or ear fibroblasts yielded higher (P < 0.05) rates of fusion than other cells (62.6-69.3 versus 33.3-38.7%). In the serum-starved group, the first cleavage after reconstruction was significantly increased in cumulus cells and ear fibroblasts, compared with oviduct cells (93.4-94.3 versus 78.8-86.0%), and oocytes reconstructed with either of these yielded more blastocysts than oocytes reconstructed with oviduct or uterine cells (40.6-43.8 versus 20.3-19.0%). We observed a similar pattern in the non-starved group, but we found a significant increase in blastocyst formation was found only in cumulus cells compared with other donor cells (42.6 versus 15.4-27.7%). Overall comparison showed that serum starvation increased the rates of cleavage and development to the blastocyst stage, but we found a statistical significance only in the cleavage rate (80.0 versus 89.5%). In Experiment 2, we transferred randomly selected 59 blastocysts that were developed from oocytes reconstructed with serum-starved cells to 44 synchronised recipients. Of those recipients, 23 became pregnant on Day 60 after transfer (52.3%) and 12 (27.3%) delivered cloned calves. The mean gestation length and birth weight was 275 +/- 8 days and 39.6 +/- 15.6 kg, respectively. Although there was no significant difference among donor cells, blastocysts that were derived from oocytes reconstructed with ear fibroblasts yielded the highest rates of pregnancy (50.0%) and delivery (27.3%). In conclusion, serum starvation is effective for improving preimplantation development of oocytes reconstructed with cumulus or ear fibroblast cells and it may positively influence on obtaining better pregnancy outcome.


Assuntos
Meios de Cultura Livres de Soro , Técnicas de Transferência Nuclear , Oócitos/fisiologia , Animais , Animais Recém-Nascidos , Blastocisto/fisiologia , Bovinos , Células Cultivadas , Fase de Clivagem do Zigoto , Transferência Embrionária/veterinária , Desenvolvimento Embrionário e Fetal , Tubas Uterinas/ultraestrutura , Feminino , Fibroblastos/ultraestrutura , Oócitos/ultraestrutura , Folículo Ovariano/ultraestrutura , Gravidez , Útero/ultraestrutura
14.
Poult Sci ; 80(11): 1527-34, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11732667

RESUMO

Two layer feeding trials were conducted to demonstrate the nutritive and economic values of recently developed high oil corn (HOC) in Korea. A corn-soybean meal-based commercial layer diet was chosen as the control diet. The yellow dent corn in the control diet was replaced with HOC to give an isocaloric diet, or replaced with HOC on a 1:1 basis to give a high energy diet. In Trial 1, 510 23-wk-old ISA Brown layers were allotted to three dietary treatments with five replicates per treatment. In Trial 2, 600 38-wk-old Hy-Line Brown layers were allotted to three dietary treatments, again with five replicates per treatment. Both trials were conducted for 15 wk. To measure the ME values of typical corn and HOC, two metabolism trials were performed with layers and adult roosters. The HOC used in this trial contained approximately 94% higher crude fat (6.60% as-fed basis) compared with typical corns. The gross energy, AMEn, and TME values of HOC, are 5.7 to 7.7% higher than those of typical corns, indicating that the energy use of each corn were similar. Oil from the HOC contains 6.5 to 8.3% more oleic acid and 6 to 7% less linoleic acid than oil from typical corns. HOC feeding, on an isocaloric basis or on 1:1 replacement with typical corn, did not exert any effect on various laying performances, including the physical quality of egg. This result reflects the quality of the commercial diet chosen as the control diet, which was already fairly good, such that the performance was already maximal. The polyunsaturated fatty acid content in yolk from hens fed HOC was higher than that from hens fed typical corns, reflecting higher linoleic acid content in the HOC. HOC feeding decreased the saturated fatty acid content in the yolk, due primarily to decreased palmitic acid. If used alone replacing typical corn completely in a layer diet, the acceptance price of HOC was estimated to be 154 won/kg when the price of typical corn was 131 won/kg (118:100). When both corns were allowed to be used, the acceptance price of HOC increased to 184 won/kg (140:100), indicating that a lot cheaper layer diet can be formulated when both HOC and typical corn are used in laying hen diet formulation.


Assuntos
Ração Animal/economia , Galinhas/fisiologia , Óleo de Milho/administração & dosagem , Dieta , Valor Nutritivo , Zea mays , Fenômenos Fisiológicos da Nutrição Animal , Animais , Gema de Ovo/química , Ácidos Graxos Insaturados/análise , Feminino , Ácido Linoleico/administração & dosagem , Ácido Oleico/administração & dosagem , Oviposição
15.
Water Res ; 35(9): 2314-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11358313

RESUMO

After multiple ethanol washings followed by distillation, concentrated benzo(a)pyrene (B(a)P) in ethanol (approximately 85 mg L(-1)) was treated by Fenton oxidation, where > 99.8% of B(a)P was removed under a pseudo-first-order reaction. GC-MS and HPLC analysis identified B(a)P-1,6-, -3,6-, and -6,12-dione as Fenton oxidation products; all of which are known to have lower toxicity than B(a)P. Microbial resistance experiments demonstrated that B(a)P-1.6-, -3.6-, and -6,12-dione are more easily degraded than B(a)P. These results indicate that the proposed treatment can be effectively applied to remediate B(a)P-contaminated soil.


Assuntos
Benzo(a)pireno/metabolismo , Poluentes do Solo/metabolismo , Benzo(a)pireno/química , Cromatografia Líquida de Alta Pressão , Etanol , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio , Ferro , Oxirredução
16.
Chemosphere ; 43(8): 1127-32, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11368229

RESUMO

In order to mitigate the strong microbial resistance of benz(a)anthracene [B(a)A] in soil, a hybrid treatment of Fenton oxidation followed microbial culture was carried out. Based on optimal Fenton oxidation. i.e., 1.0 ml of ethanol, 0.2 ml of 0.5 M Fe2+, and 0.3 ml of 30% H2O2 per 1 g of 500 mg B(a)A/kg soil, about 43% of B(a)A-7,12-dione was generated during oxidation of 97% B(a)A. When the comparative biodegradability between B(a)A-contaminated soil and B(a)A-contaminated soil after Fenton oxidation was examined, it was found that 98% of B(a)A-7,12-dione degraded after 63 d in comparison with only 12% of B(a)A over the same period; results demonstrating that Fenton oxidation enhances biodegradability of B(a)A through B(a)A-7,12-dione.


Assuntos
Benzo(a)Antracenos/metabolismo , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Peróxido de Hidrogênio , Ferro , Oxirredução , Microbiologia do Solo
17.
FEBS Lett ; 491(1-2): 4-8, 2001 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-11226408

RESUMO

Upon epidermal growth factor treatment, phospholipase C-gamma1 (PLC-gamma1) translocates from cytosol to membrane where it is phosphorylated at tyrosine residues. Caveolae are small plasma membrane invaginations whose structural protein is caveolin. In this study, we show that the translocation of PLC-gamma1 and its tyrosine phosphorylation are localized in caveolae by caveolin-enriched low-density membrane (CM) preparation and immunostaining of cells. Pretreatment of cells with methyl-beta-cyclodextrin (MbetaCD), a chemical disrupting caveolae structure, inhibits the translocation of PLC-gamma1 to CM as well as phosphatidylinositol (PtdIns) turnover. However, MbetaCD shows no effect on tyrosine phosphorylation level of PLC-gamma1. Our findings suggest that, for proper signaling, PLC-gamma1 phosphorylation has to occur at PtdInsP(2)-enriched sites.


Assuntos
Cavéolas/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Isoenzimas/metabolismo , Fosfatidilinositóis/metabolismo , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Tirosina/metabolismo , beta-Ciclodextrinas , Animais , Western Blotting , Células COS , Cavéolas/enzimologia , Cavéolas/ultraestrutura , Caveolina 1 , Caveolinas/metabolismo , Compartimento Celular , Linhagem Celular , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Ciclodextrinas/farmacologia , Hidrólise , Fosfolipase C gama , Fosforilação , Testes de Precipitina
18.
Chemosphere ; 42(4): 345-50, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11100784

RESUMO

Batch photocatalytic degradation of 1000-ppm gaseous perchloroethylene (PCE) was conducted with UV irradiation such that nearly 100% was decomposed within 10 min. The main intermediate and final product were identified as trichloroacetylchloride (TCAC) and hydrogen chloride (HCl), respectively, and minor ones as dichloroacetic acid (DCAC), monochloroacetic acid (MCAC), carbon tetrachloride, chloroform, and phosgene. More than 90% of Cl- equivalent, i.e., the sum of the chlorine number in PCE, intermediates, and HCl, was compensated for during the time of PCE degradation; a result indicating that no other major chlorinated intermediates are present during the time of PCE degradation. In a similar experiment, 500 ppm of gaseous TCAC degraded into HCl within 3 h without producing DCAC or MCAC, where like PCE, more than 90% of Cl- equivalent, i.e., the sum of the chlorine number in TCAC and HCl, was compensated for during time of TCAC degradation. Accordingly, gaseous PCE is concluded to predominantly follow a degradation pathway of PCE --> TCAC --> HCl.


Assuntos
Poluentes Ambientais/análise , Tetracloroetileno/química , Cromatografia Gasosa-Espectrometria de Massas , Gases , Cinética , Tetracloroetileno/análise
19.
Chemosphere ; 42(4): 431-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11100796

RESUMO

Five recalcitrant polycyclic aromatic hydrocarbons (PAHs) in ethanol were subjected to Fenton oxidation, and following GC-MS identification of respective oxidation products, their oxidation positions were compared to those predicted by Frontier electron density. Quinone forms of oxidation products were identified in each PAH. With the exception of fluorene, oxidation positions of quinone forms of products of acenaphthylene, anthracene, benz(a)anthracene, and benzo(a)pyrene corresponded with predicted positions in which Frontier electron density was high. From these results, it appears that determining the Frontier electron density of a PAH is a promising method for predicting the Fenton oxidation position.


Assuntos
Hidrocarbonetos Aromáticos/química , Peróxido de Hidrogênio/farmacologia , Ferro/farmacologia , Oxirredução/efeitos dos fármacos , Etanol , Cromatografia Gasosa-Espectrometria de Massas , Valor Preditivo dos Testes , Solventes
20.
Neurosci Lett ; 294(2): 130-2, 2000 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-11058804

RESUMO

Bradykinin (BK) activates phospholipase D (PLD) and induces several responses such as catecholamine secretion, collapse of growth cones, and gene expression in PC12 pheochromocytoma cells. Although two distinct PLD isozymes, PLD1 and PLD2, have been cloned from mammalian cells, the regulatory mechanism for each PLD isozyme by BK is not clear. In our present study, we investigated the activation mechanism of PLD2 by BK in PLD2-overexpressing PC12 cells. BK stimulated PLD2 activity in a concentration-dependent manner within 1 min and this activation was inhibited by pretreatment of the cells with protein kinase C (PKC) inhibitor. PKCalpha and PKCdelta translocated from cytosol to membrane upon BK treatment, and rottlerin potently inhibited the activation of PLD2 by BK. These results suggest that BK activates PLD2 via PKCdelta in PC12 cells.


Assuntos
Bradicinina/metabolismo , Isoenzimas/metabolismo , Células PC12/enzimologia , Fosfolipase D/metabolismo , Proteína Quinase C/metabolismo , Acetofenonas/farmacologia , Animais , Benzopiranos/farmacologia , Bradicinina/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Membrana Celular/enzimologia , Citosol/enzimologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Isoenzimas/antagonistas & inibidores , Maleimidas/farmacologia , Células PC12/citologia , Fosfolipase D/genética , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C-alfa , Proteína Quinase C-delta , Ratos , Transdução de Sinais/efeitos dos fármacos , Transfecção
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