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1.
Faraday Discuss ; 191: 105-116, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27412078

RESUMO

We synthesize robust clusters of gold satellites positioned with tetrahedral symmetry on the surface of a patchy silica core by adsorption and growth of gold on the patches. First we conduct emulsion polymerization of styrene in the presence of 52 nm silica seeds whose surface has been modified with methacryloxymethyltriethoxysilane (MMS). We derive four-dimple particles from the resulting silica/polystyrene tetrapods. Polystyrene chains are covalently bound to the silica surface within the dimples due to the MMS grafts and they may be thiolated to induce adsorption of 12 nm gold particles. Using chloroauric acid, ascorbic acid and sodium citrate at room temperature, we grow gold from these 12 nm seeds without detachment from or deformation of the dimpled silica surface. We obtain gold satellites of tunable diameter up to 140 nm.

2.
Hum Exp Toxicol ; 35(4): 428-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26089033

RESUMO

The present study has been designed to investigate the ameliorative effect of grape seed proanthocyanidins (GSP) on cadmium (Cd)-induced oxidative damage in rat erythrocytes. Twenty four male Wistar rats were divided into four groups: control, GSP-treated group (100 mg kg(-1) body weight (BW)), Cd-treated group (cadmium chloride, 5 mg kg(-1) BW), and GSP + Cd-treated group in which GSP was orally pre-administered 90 min before Cd intoxication for 4 weeks. At the end of the experimental period, blood samples were collected by cardiac puncture and were processed for various biochemical estimations. The extent of oxidative damage in isolated rat erythrocyte membrane was assessed by measuring lipid peroxidation, enzymatic and non-enzymatic content, calcium ion (Ca(2+))/magnesium ion (Mg(2+))-ATPase and sodium ion (Na(+))/potassium ion (K(+))-ATPase activities, free iron, calcium, hydrogen peroxide (H2O2) concentration, and osmotic fragility. Our results unveiled that Cd intoxication significantly increased the erythrocyte lipid peroxidation markers and decreased the activity of enzymatic and non-enzymatic markers in erythrocytes. Conversely, GSP pretreatment significantly prevented the decrease in the activities of antioxidant enzymes and membrane-bound ATPases. GSP also restored the levels of iron, calcium, and H2O2 in Cd-treated rats. Conformational changes in erythrocytes of various groups were also determined using morphological and ultrastructural electron microscopic analysis. The findings of our study clearly revealed that GSP affords superior protection against Cd-induced reactive oxygen species generation, lipid peroxidation, and free radical generation in Cd-treated rats, which presumably reflects the ability of this flavonoid to protect erythrocytes and lymphocytes of rats from the toxic effects of Cd.


Assuntos
Cádmio/toxicidade , Eritrócitos/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Linfócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proantocianidinas/farmacologia , Animais , Antioxidantes/metabolismo , Cádmio/sangue , Cálcio/sangue , Cálcio/metabolismo , Extrato de Sementes de Uva/química , Peróxido de Hidrogênio , Ferro/sangue , Ferro/metabolismo , Masculino , Estrutura Molecular , Proantocianidinas/química , Ratos , Ratos Wistar
3.
Oncogene ; 35(17): 2197-207, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-26257057

RESUMO

Enhanced sensitivity to Wnts is an emerging hallmark of a subset of cancers, defined in part by mutations regulating the abundance of their receptors. Whether these mutations identify a clinical opportunity is an important question. Inhibition of Wnt secretion by blocking an essential post-translational modification, palmitoleation, provides a useful therapeutic intervention. We developed a novel potent, orally available PORCN inhibitor, ETC-1922159 (henceforth called ETC-159) that blocks the secretion and activity of all Wnts. ETC-159 is remarkably effective in treating RSPO-translocation bearing colorectal cancer (CRC) patient-derived xenografts. This is the first example of effective targeted therapy for this subset of CRC. Consistent with a central role of Wnt signaling in regulation of gene expression, inhibition of PORCN in RSPO3-translocated cancers causes a marked remodeling of the transcriptome, with loss of cell cycle, stem cell and proliferation genes, and an increase in differentiation markers. Inhibition of Wnt signaling by PORCN inhibition holds promise as differentiation therapy in genetically defined human cancers.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Proteínas de Membrana/genética , Proteínas Wnt/genética , Aciltransferases , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Processamento de Proteína Pós-Traducional , Células-Tronco/efeitos dos fármacos , Proteínas Wnt/antagonistas & inibidores , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Vector Borne Dis ; 52(3): 193-200, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26418648

RESUMO

BACKGROUND & OBJECTIVES: Fly ash is produced in huge quantities by the various thermal power stations in India. This thermal waste has been employed as a carrier material in the preparation of a biopesticidal water dispersible powder (WDP) formulation for use against mosquitoes. In the present investigation, this newly developed fly ash based WDP formulation was evaluated in natural breeding habitats of mosquito. METHODS: Fly ash based WDP formulation of Bacillus thuringiensis var. israelensis (VCRC B17) was evaluated for its efficacy and residual activity in aquatic habitats supporting breeding of Culex quinquefasciatus, the vector of lymphatic filariasis in Neyveli Township, Neyveli Lignite Corporation, India for a period of one month. RESULTS: At an application rate of 10 kg/ha, the WDP was effective for five days regardless of the habitat, and provided 80-100% reduction in larval abundance of Cx. quinquefasciatus. INTERPRETATION & CONCLUSION: The study indicates that for continued control of immature density and prevention of adult emergence, a weekly application of this formulation is necessary. This study also showed that fly ash based formulations can be used for immediate control of mosquitoes in different types of habitats and has also brought out a new avenue for the utilization of coal ash.


Assuntos
Bacillus thuringiensis/fisiologia , Agentes de Controle Biológico/farmacologia , Cinza de Carvão , Culex/efeitos dos fármacos , Culex/fisiologia , Ecossistema , Controle Biológico de Vetores/métodos , Animais , Índia , Resultado do Tratamento , Água/parasitologia
5.
Pak J Biol Sci ; 15(6): 296-300, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24175427

RESUMO

The present study is focused to see the effect of crustacean neuroendocrine organs on the water and calcium metabolism which is very much important for the osmoregulatory functions. Since the experiments were carried out to investigate the control of water contents and calcium concentration in the crab, Ocypode macrocera. The animals were collected from the shore of the Bay of the Bengal near Annan Koil one among the biggest landing centers of south east coast of Tamil Nadu, India. The data revealed that water content in the hepatopancreas and thoracic muscle of the control crab were 70.16 and 79.86%, respectively, whereas in the experimental ones, the values were 80.32 and 87.44% after eyestalk removal and 54.52 and 66.98% after eyestalk extract injection. Calcium concentration in both the hepatopancreas and thoracic muscle of the control crab were 2.16 and 2.14 mg g(-1), respectively, whereas in the experimental animals the values were 2.76 and 3.52 mg g(-1) in the eyestalkless crabs and 1.52 and 1.57 mg g(-1) after eyestalk extract injection, respectively. Hence it was observed the % of water content is more in eyestalk less crabs as compared to that of control and injected. The roles of neurosecretory secretions, which control these parameters, were discussed. The ability for Ocypode macrocera to adapt rapidly and maintain homeostasis in a wide range of abnormality supports the fact that Ocypode macrocera are a suitable species for land-based aquaculture in ponds as well as critical condition where rapid fluctuation in salinity can occur.


Assuntos
Água Corporal , Cálcio/metabolismo , Células Neuroendócrinas/fisiologia , Animais , Crustáceos , Osmorregulação
6.
J Environ Qual ; 38(4): 1466-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19465722

RESUMO

There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hypothesis that photosynthetic pigments concentrations and CO(2) assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots [barley (Hordeum vulgare) and ryegrass (Secale cereale)] and dicots [canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)] on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates (

Assuntos
Carbono , Carvão Mineral , Produtos Agrícolas/crescimento & desenvolvimento , Material Particulado , Fotossíntese , Pigmentos Biológicos/análise , Cinza de Carvão , Germinação
7.
J Environ Qual ; 37(3): 1263-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18453446

RESUMO

To explore the agronomic potential of an Australian coal fly ash, we conducted two glasshouse experiments in which we measured chlorophyll fluorescence, CO2 assimilation (A), transpiration, stomatal conductance, biomass accumulation, seed yield, and elemental uptake for canola (Brassica napus) grown on soil amended with an alkaline fly ash. In Experiment 1, application of up to 25 Mg/ha of fly ash increased A and plant weight early in the season before flowering and seed yield by up to 21%. However, at larger rates of ash application A, plant growth, chlorophyll concentration, and yield were all reduced. Increases in early vigor and seed yield were associated with enhanced uptake of phosphorus (P) by the plants treated with fly ash. Fly ash application did not influence accumulation of B, Cu, Mo, or Zn in the stems at any stage of plant growth or in the seed at harvest, except Mo concentration, which was elevated in the seed. Accumulation of these elements was mostly in the leaves, where concentrations of Cu and Mo increased with any amount of ash applied while that of B occurred only with ash applied at 625 Mg/ha. In Experiment 2, fly ash applied at 500 Mg/ha and mixed into the whole 30 cm soil core was detrimental to growth and yield of canola, compared with restricting mixing to 5 or 15 cm depth. In contrast, application of ash at 250 Mg/ha with increasing depth of mixing increased A and seed yield. We concluded that fly ash applied at not more than 25 Mg/ha and mixed into the top 10 to 15 cm of soil is sufficient to obtain yield benefits.


Assuntos
Brassica/metabolismo , Carbono , Material Particulado , Solo , Brassica/crescimento & desenvolvimento , Brassica/fisiologia , Cinza de Carvão
8.
Environ Pollut ; 145(3): 778-86, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16831500

RESUMO

A greenhouse study was conducted to determine if concentrations of fluoride (F), which would be added to acid soils via P fertilisers, were detrimental to barley root growth. Increasing rates of F additions to soil significantly increased the soil solution concentrations of aluminium (Al) and F irrespective of the initial adjusted soil pH, which ranged from 4.25 to 5.48. High rates of F addition severely restricted root growth; the effect was more pronounced in the strongly acidic soil. Speciation calculations demonstrated that increasing rates of F additions substantially increased the concentrations of Al-F complexes in the soil. Stepwise regression analysis showed that it was the combination of the activities of AlF2(1+) and AlF(2+) complexes that primarily controlled barley root growth. The results suggested that continuous input of F to soils, and increased soil acidification, may become an F risk issue in the future.


Assuntos
Alumínio/análise , Fertilizantes/toxicidade , Fluoretos/farmacologia , Hordeum/crescimento & desenvolvimento , Poluentes do Solo/farmacologia , Alumínio/toxicidade , Compostos de Alumínio/análise , Cálcio/deficiência , Fluoretos/análise , Fluoretos/toxicidade , Hordeum/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Fósforo/toxicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Solo/análise , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
9.
J Environ Manage ; 79(2): 173-87, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16256262

RESUMO

Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996-2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200 t/ha), with and without press mud (10 t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50 t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20 t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p < 0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20 t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5-10.2% with various dosages of LFA. The optimum dosage of LFA was 20 t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20 t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20 t/ha and repeat applications at 50 t/ha. One-time and repeat applications of LFA of up to 20 t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of gamma-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20 t/ha of LFA, the crop yield decreased significantly (p < 0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and gamma-emitters in mine spoil and crop produce is also discussed.


Assuntos
Agricultura/métodos , Carbono/química , Fertilizantes , Oryza/crescimento & desenvolvimento , Solo/análise , Carbono/farmacologia , Cinza de Carvão , Relação Dose-Resposta a Droga , Índia , Metais Pesados/química , Mineração , Oryza/efeitos dos fármacos , Material Particulado , Solo/normas
10.
Hum Antibodies ; 9(3): 171-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10690631

RESUMO

Immunocytochemical localisation of mutant p53 in breast tumours serves as a potential prognostic molecular marker. In order to study the expression of p53 protein in breast cancer which constitutes the second most common malignancy in the South Indian female population, MAb CIBCVMC12 has been generated against human p53 protein isolated and purified from bacterial cell lysate of E.coli carrying the plasmid T 7-7 Hup53 grown in Luria broth to induce the expression of p53. The positive clones selected by ELISA were found to exhibit strong staining of nuclear p53 in both fresh and archival paraffin embedded breast tumour tissue sections. Commercial MAb D 07 against p53 was used as control. In immunoprecipitation, this MAb of IgG2b isotype was found to bind specifically to a protein of 53 kD. Immuno cyto chemical assay of normal, benign and malignant breast tissues of different histological types revealed that the majority of tumour cells were strong positive in the case of infiltrating ductal and lobular carcinomas, the staining being less intense for in situ carcinoma. The test for normal and benign tissues was negative. The staining patterns were comparable with those of control antibody. These results suggest that the MAb generated is specific to p53. The p53 protein expression was compared with the estrogen receptor (ER) status for 50 breast tumours which revealed that 38% of these were p53 positive and of these two were ER+. Among the p53 negative tumours, 48% were found to be ER+. A comparison of the p53 expression for 100 breast cancer patients indicated that 57% of the tumours were p53 negative and these patients had a longer overall 5 year survival rate and recurrent free interval which is statistically very significant. These results might suggest that p53 positive tumours are more aggressive biologically with poor prognosis.


Assuntos
Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Carcinoma Lobular/química , Proteína Supressora de Tumor p53/análise , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/mortalidade , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Índia , Recidiva Local de Neoplasia , Prognóstico , Receptores Estrogênicos/análise , Taxa de Sobrevida , Proteína Supressora de Tumor p53/imunologia , Proteína Supressora de Tumor p53/isolamento & purificação
11.
Odontostomatol Trop ; 13(2): 67-71, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2270214

RESUMO

The authors study the dose of radiation received in the Gonadal areas during intra-oral or panoramic radiography performed at the college of Dentistry in Riyadh, Saudi Arabia. The results show a negligible generic risk.


Assuntos
Gônadas/efeitos da radiação , Radiografia Dentária/efeitos adversos , Recursos Humanos em Odontologia , Feminino , Humanos , Masculino , Doses de Radiação , Radiografia Panorâmica/efeitos adversos , Arábia Saudita
12.
Genitourin Med ; 63(6): 393-5, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3428897

RESUMO

Squamous papillae in the vestibule are common. They were once considered to be normal variants of female anatomy, but reports of the viral aetiology of such lesions are emerging. When they are symptomatic, squamous papillae can lead to problems in sexual relationships between healthy partners. Here we report a case that responded well to treatment.


Assuntos
Papiloma/patologia , Neoplasias Vulvares/patologia , Adulto , Feminino , Humanos , Papiloma/tratamento farmacológico , Ácido Tricloroacético/uso terapêutico , Vulva/patologia , Neoplasias Vulvares/tratamento farmacológico
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