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1.
Br J Cancer ; 102(2): 403-13, 2010 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-19997104

RESUMO

BACKGROUND: Prostate cancer (CaP) preferentially metastasises to the bone, and we have previously shown that the poly-unsaturated fatty acid (PUFA) arachidonic acid (AA) is a potent stimulator of CaP invasion. Here we present that AA promotes CaP invasion by inducing bone marrow adipocyte formation. METHODS: Boyden invasion-chamber assays assessed the ability of dietary oils, their PUFA components, and specific PUFA-loaded adipocytes to induce PC-3 invasion. Lipid transfer and metabolism was followed using deuterated AA and Fourier Transform Infrared spectroscopy (FTIR). RESULTS: Poly-unsaturated fatty acid constituents, but not their corresponding dietary oils, induced PC-3 invasion. PUFAs induce bone marrow adipocyte (BM-Ad) differentiation with AA inducing higher levels of BM-Ad differentiation, as compared with other PUFAs (3998+/-514.4 vs 932+/-265.8; P=0.00002), which stimulated greater PC-3 invasion than free AA (22 408.5+/-607.4 vs 16 236+/-313.9; P=0.01111) or adipocytes generated in the presence of other PUFAs. In bone marrow co-culture PC-3 and BM-Ad interactions result in direct uptake and metabolism of AA by PC-3 cells, destruction of the adipocyte and subsequent formation of a bone metastasis. CONCLUSION: The data supports the hypothesis that AA not only promotes CaP invasion, it also prepares the 'soil', making it more supportive for implantation and propagation of the migrating metastatic cell.


Assuntos
Adipócitos/efeitos dos fármacos , Ácido Araquidônico/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Ácidos Graxos Ômega-6/farmacologia , Neoplasias da Próstata/metabolismo , Adipócitos/metabolismo , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Humanos , Masculino , Invasividade Neoplásica , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/secundário
2.
Appl Radiat Isot ; 67(7-8 Suppl): S31-3, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19447633

RESUMO

This paper describes results to-date from a human pharmacokinetic study which began recruitment in December 2007. Results are presented for a single patient recruited in December 2007. A second patient was recruited in July 2008 but detailed data are not available at the time of writing. The trial is an open-label, non-comparative, non-therapeutic study of BPA-mannitol in patients with high-grade glioma, who will be undergoing stereotactic brain biopsy as part of the diagnostic process before definitive treatment. The study investigates the route of infusion (intra-venous (IV) or intra-carotid artery) and in each case will assess the effect of administration of mannitol as a blood-brain barrier disrupter. All cohorts will receive a 2 h infusion of BPA-mannitol, and for some cohorts an additional mannitol bolus will be administered at the beginning of this infusion. Measurements are made by inductively coupled plasma mass spectrometry (ICP-MS) of (10)B concentration in samples of blood, urine, extra-cellular fluid in normal brain (via a dialysis probe), brain tissue around tumour and tumour tissue. Additional analysis of the tumour tissue is performed using secondary ion mass spectrometry (SIMS). The first patient was part of the cohort having intra-venous infusion without mannitol bolus. No serious clinical problems were experienced and the assay results can be compared with available patient data from other BNCT centres. In particular we note that the peak (10)B concentration in blood was 28.1 mg/ml for a total BPA administration of 350 mg/kg which is very consistent with the previous experience with BPA-fructose reported by the Helsinki group.


Assuntos
Compostos de Boro/farmacocinética , Compostos de Boro/uso terapêutico , Terapia por Captura de Nêutron de Boro/métodos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Glioma/metabolismo , Glioma/radioterapia , Fenilalanina/análogos & derivados , Radiossensibilizantes/farmacocinética , Radiossensibilizantes/uso terapêutico , Idoso , Barreira Hematoencefálica , Compostos de Boro/administração & dosagem , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Humanos , Masculino , Manitol/administração & dosagem , Fenilalanina/administração & dosagem , Fenilalanina/farmacocinética , Fenilalanina/uso terapêutico , Radiossensibilizantes/administração & dosagem , Reino Unido
3.
Appl Surf Sci ; 255(4): 1190-1192, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19430585

RESUMO

With the chemical imaging capability of ToF-SIMS, biological molecules are identified and localized in membranes without any chemical labels. We have developed a model membrane system made with supported Langmuir-Blodgett (LB) monolayers. This simplified model can be used with different combinations of molecules to form a membrane, and thus represents a bottom-up approach to study individual lipid-lipid or lipid-protein interactions. We have used ternary mixtures of sphingomyelin (SM), phosphatidylcholine (PC), and cholesterol (CH) in the model membrane to study the mechanism of domain formation and interactions between phospholipids and cholesterol. Domain structures are observed only when the acyl chain saturation is different for SM and PC in the mixture. The saturated lipid, whether it is SM or PC, is found to be localized with cholesterol, while the unsaturated one is excluded from the domain area. More complicated model membranes which involve a functional membrane protein glycophorin are also investigated and different membrane properties are observed compared to the systems without glycophorin.

4.
Anal Bioanal Chem ; 387(5): 1621-31, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17268776

RESUMO

Prostate cancer (CaP) cells preferentially metastasise to the bone marrow, a microenvironment that plays a substantial role in the sustenance and progression of the CaP tumour. Here we use a combination of FTIR microspectroscopy and histological stains to increase molecular specificity and probe the biochemistry of metastatic CaP cells in bone marrow tissue derived from a limited source of paraffin-embedded biopsies of different patients. This provides distinction between the following dominant metabolic processes driving the proliferation of the metastatic cells in each of these biopsies: glycerophospholipid synthesis from triacylglyceride, available from surrounding adipocytes, in specimen 1, through significantly high (p < or = 0.05) carbohydrate (8.23 +/- 1.44 cm(-1)), phosphate (6.13 +/- 1.5 cm(-1)) and lipid hydrocarbon (24.14 +/- 5.9 cm(-1)) signals compared with the organ-confined CaP control (OC CaP), together with vacuolation of cell cytoplasm; glycolipid synthesis in specimen 2, through significantly high (p < or = 0.05) carbohydrate (5.51 +/- 0.04 cm(-1)) and high lipid hydrocarbon (17.91 +/- 2.3 cm(-1)) compared with OC CaP, together with positive diastase-digested periodic acid Schiff staining in the majority of metastatic CaP cells; glycolysis in specimen 3, though significantly high (p < or = 0.05) carbohydrate (8.86 +/- 1.78 cm(-1)) and significantly lower (p < or = 0.05) lipid hydrocarbon (11.67 +/- 0.4 cm(-1)) than OC CaP, together with negative diastase-digested periodic acid Schiff staining in the majority of metastatic CaP cells. Detailed understanding of the biochemistry underpinning the proliferation of tumour cells at metastatic sites may help towards refining chemotherapeutic treatment.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Medula Óssea/metabolismo , Neoplasias da Medula Óssea/secundário , Lipídeos/química , Neoplasias da Próstata/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Biopolímeros/química , Neoplasias da Medula Óssea/diagnóstico , Neoplasias da Medula Óssea/patologia , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Projetos Piloto , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
5.
Anal Chem ; 77(6): 1740-5, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15762580

RESUMO

We present a TOF-SIMS analysis of the cell surface differences between four yeast strains from two species, Candida glabrata and Saccharomyces cerevisiae (haploid strains BY4742 and BY4741 and the derived diploid BY4743). The study assesses the suitability of TOF-SIMS analysis in combination with statistical methods (principal component analysis, Fisher's discriminant analysis, and cluster analysis) for the discrimination between the four yeast strains. We demonstrate that a combination of these statistical methods identifies 34 ions, from a total data set of 1200, which can be used to distinguish between the four yeasts. The study discusses the assignments of surface cell membrane phospholipids for the identified ions and the resulting differences in the phospholipid pattern between the four yeasts, particularly in relation to ploidy and budding pattern. The method shows that fatty acids, phosphatidylglycerols, phosphatidylethanolamines, phosphatidylserines, and phosphatidylcholines, as well as cardiolipins, are of diagnostic importance.


Assuntos
Candida glabrata/química , Técnicas de Tipagem Micológica/métodos , Fosfolipídeos/análise , Saccharomyces cerevisiae/química , Espectrometria de Massa de Íon Secundário/métodos , Cardiolipinas/análise , Análise por Conglomerados , Ácidos Graxos/análise
6.
Biopolymers ; 77(1): 18-30, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15558657

RESUMO

Synchrotron-based Fourier transform infrared (SR-FTIR) microspectroscopy is a powerful bioanalytical technique for the simultaneous analysis of lipids, proteins, carbohydrates, and a variety of phosphorylated molecules within intact cells. SR-FTIR microspectroscopy can be used in the imaging mode to generate biospectroscopic maps of the distribution and intensity profiles of subcellular biomolecular domains at diffraction-limited spatial resolution. However, the acquisition of highly spatially resolved IR images of cells is not only a function of instrumental parameters (source brightness, sampling aperture size) but also the cell preparation method employed. Additionally, for the IR data to be biochemically relevant the cells must be preserved in a life-like state without introducing artefacts. In the present study we demonstrate, for the first time, the differences in biomolecular localizations observed in SR-FTIR images of cells fixed by formalin, formalin-critical point drying (CPD), and glutaraldehyde-osmium tetroxide-CPD, using the PC-3 prostate cancer cell line. We compare these SR-FTIR images of fixed cells to unfixed cells. The influence of chemical fixatives on the IR spectrum is discussed in addition to the biological significance of the observed localizations. Our experiments reveal that formalin fixation at low concentration preserves lipid, phosphate, and protein components without significantly influencing the IR spectrum of the cell.


Assuntos
Frações Subcelulares/ultraestrutura , Animais , Linhagem Celular , Glutaral , Microscopia Eletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Síncrotrons
7.
J Pathol ; 201(1): 99-108, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12950022

RESUMO

Fourier transform infrared (FTIR) microspectroscopy has been applied to a study of prostate cancer cell lines derived from different metastatic sites and to tissue from benign prostate and Gleason-graded malignant prostate tissue. Paraffin-embedded tissue samples were analysed by FTIR, after mounting onto a BaF(2) plate and subsequent removal of wax using Citroclear followed by acetone. Cell lines were analysed as aliquots of cell suspension held between two BaF(2) plates. It was found that the ratio of peak areas at 1030 and 1080 cm(-1), corresponding to the glycogen and phosphate vibrations respectively, suggests a potential method for the differentiation of benign from malignant cells. The use of this ratio in association with FTIR spectral imaging provides a basis for estimating areas of malignant tissue within defined regions of a specimen. Initial chemometric treatment of FTIR spectra, using the linear discriminant algorithm, demonstrates a promising method for the classification of benign and malignant tissue and the separation of Gleason-graded CaP spectra. Using the principle component analysis, this study has achieved for the first time the separation of FTIR spectra of prostate cancer cell lines derived from different metastatic sites.


Assuntos
Adenocarcinoma/patologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Células Cultivadas , Diagnóstico Diferencial , Células Epiteliais/patologia , Humanos , Masculino , Análise Multivariada , Projetos Piloto , Próstata/anatomia & histologia , Células Tumorais Cultivadas
8.
Arch Environ Contam Toxicol ; 6(2-3): 241-8, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-901004

RESUMO

3-Chloro-4-methyl benzamine HCl (DRC-1339), an avian toxicant, was fed to five species of birds for periods up to 120 days. The 30-day LC50 of uniformly treated feed for starlings was 4.7 ppm and the 90-day LC50 was 1.0 ppm. The 28-day LC50 for coturnix was 18 ppm. The 30-day LC50 for pigeons was less than 100 ppm. Pheasants fed diets containing 2% DRC-1339 baits diluted to a rate of 286 ppm of DRC-1339 died within 22 days. Bobwhite quail fed similar diets suffered some mortality at levels as low as 2.9 ppm, but most survived 10 times this dosage level for the 120-day test period. Application of the Kenaga "Index of Chronicity", resulted in the conclusion that DRC-1339 was cumulatively toxic to birds. Reproduction in coturnix was adversely affectd by treatments at 10 ppm of DRC-1339 and above. Reproduction in pigeons was adversely affectd by a treatment of 25 ppm. In coturnix, DRC-1339 caused an increased incidence of egg breakage and decreased both egg and live chick production. In pigeons, DRC-1339 caused an increase in the proportion of infertile eggs. Reproductive ability to first generation offspring was not affected when parent coturnix and pigeons were fed DRC-1339. These data emphasize the need for care in the use of DRC-1339. The bait should be used only as registered and care exercised in storage and disposal of unused baits to avoid poisoning of nontarget species.


Assuntos
Aves/fisiologia , Hidrocarbonetos Clorados/toxicidade , Praguicidas/toxicidade , Animais , Colinus/fisiologia , Columbidae/fisiologia , Coturnix/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Feminino , Masculino , Reprodução/efeitos dos fármacos , Especificidade da Espécie , Fatores de Tempo
10.
Bull Environ Contam Toxicol ; 14(6): 641-7, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1203576

RESUMO

Methiocarb (4-methylthio-3, 5-xylyl N-methyl carbamate, Mesurol, Bay (3744), a bird repellent, was fed in concentrations of 100 to 1,000 ppm to common grackles (Quiscalus quiscula), mourning doves (Zenaida macroura), and breeding pairs of coturnix quail (Coturnix coturnix) to investigate the possibility of cumulative intoxication. Although aversion to treated diets was readily apparent in most of the tests, the 28- to 30-day median lethal concentration (LC50) was determined to be greater than 100 ppm for grackles, 630 ppm (95% confidence limits, 480-830 ppm) for doves, and greater than 1,000 ppm for coturnix quail. Methiocarb appeared to be noncumulative when measured by an index of chronicity: birds consumed several LD50 doses during a day's feeding, and when deaths occurred, they appeared to be due to acute intoxication. Egg production and live chick production were not affected in coturnix fed 100 ppm but were reduced at 316 and 1,000 ppm.


Assuntos
Aves/fisiologia , Coturnix/fisiologia , Inseticidas/toxicidade , Metiocarb/toxicidade , Codorniz/fisiologia , Reprodução/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Masculino , Metiocarb/farmacologia , Especificidade da Espécie
11.
Bull Environ Contam Toxicol ; 13(6): 758-64, 1975 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1139060

RESUMO

When male and female coturnix quail (Coturnix coturnix) were given a single subacute oral dose (5.62 mg/kg) of the avian frightening agent 4-aminopyridine (4AP) and paired with untreated mates, there was no effect on the reproductive performance of males; egg production of females was reduced the third week after treatment but recovered during the fourth week. Chronic exposure to 31.6, 100, and 316 ppm of 4AP in the diet of mated pairs did not affect reproductive performance during or after the 4- or 6-week period the chemical was fed, but no birds fed 1,000 ppm produced live chicks after treatment began and all died within 3 weeks. The 28-day LC50 of 4AP was determined to be 447 ppm for male coturnix and 562 ppm for females. F1 progeny from quail fed 31.6, 100, and 316 ppm 4AP and randomly mated at maturity showed no reproductive effects from their parents' exposure.


Assuntos
Coturnix/fisiologia , Piridinas/farmacologia , Codorniz/fisiologia , Reprodução/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Dieta , Casca de Ovo/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Humanos , Dose Letal Mediana , Masculino , Piridinas/toxicidade , Fatores de Tempo
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