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1.
Chemosphere ; 285: 131485, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34265719

RESUMO

Irrigation restrictions due to drought periods related to climate change, would affect different crops, especially to non-food crops. In this regard the effect of irrigation reduction should be studied in energy crops in order to obtain a sustainable bioenergy cropping system. Arundo donax, has been considered a crop with high water requirements, it has nevertheless been proven to be drought tolerant. However, there is a lack of knowledge on the effect of reduced irrigation combined with the use of different fertilizers. This work studied the combined effect of value-added products (VAPs) from wastewater (treated sewage sludge) or traditional inorganic fertilizers, and irrigation reduction in Arundo donax crop in a 2-year pot experiment. Plant biometric characteristics, chemical properties and biomass yield were studied as well as the effect of treatment on soil properties. Results showed that under reduced irrigation conditions, biomass production was reduced, especially during the second year. Organic treatments from sewage sludge minimize the effect of irrigation reduction. In these treatments, biomass yield for reduced irrigation was similar to that of the control treatment with irrigation at field capacity. For this reason, it is recommended to use VAPs from wastewater as organic amendments enabling water restriction with lower effect on Arundo production.


Assuntos
Poaceae , Águas Residuárias , Biomassa , Fertilizantes , Esgotos , Solo
2.
Chemosphere ; 252: 126576, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443267

RESUMO

Phytoremediation using high production crops could be an alternative for the recovery of metals polluted soils. In this sense, the Arundo donax L. energy crop has shown tolerance to moderate concentrations of heavy metals. The objective of this work was to test the tolerance of micropropagated plants of Arundo donax to increasing concentrations of cadmium, chromium, cooper, nickel and lead, in an in vitro culture medium. Biomass production and concentration of heavy metal in shoots and roots were analyzed. Results showed that heavy metals were accumulated mostly in subterranean organs. The increase in heavy metal concentration was dose dependent and not always follows a linear relationship. Arundo donax showed a broad tolerance to cadmium (0.5 mM), chromium (0.2 mM), cooper (2 mM), nickel (0.5 mM) and lead (1 mM). In relation to cooper, Arundo donax showed a hyperaccumulative potential. These results suggest the potential use of Arundo donax in the phytomanagement of polluted soils although further studies should be carried out using polluted soils.


Assuntos
Biodegradação Ambiental , Poaceae/fisiologia , Poluentes do Solo/metabolismo , Biomassa , Cádmio , Tolerância a Medicamentos , Metais Pesados , Níquel , Raízes de Plantas/química , Solo , Poluentes do Solo/análise
3.
Hum Psychopharmacol ; 22(4): 199-210, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17457961

RESUMO

Recent data suggest that the complexation of standardised Ginkgo biloba extract (GBE) with soy-derived phospholipids enhances the bioavailability of GBE's active components. The current study therefore aimed to assess the comparative cognitive and mood effects of a low dose of GBE and products complexing the same extract with either phosphatidylserine or phosphatidylcholine. The study utilised a placebo-controlled, multi-dose, double-blind, balanced-crossover design. Twenty-eight healthy young participants received 120 mg GBE, 120 mg GBE complexed with phosphatidylserine (Virtiva), 120 mg GBE complexed with phosphatidylcholine and a matching placebo, on separate days 7 days apart. Cognitive performance was assessed using the Cognitive Drug Research (CDR) computerised test battery and Serial Subtraction tasks immediately prior to dosing and at 1, 2.5, 4 and 6 h thereafter. The primary outcome measures were the four aspects of cognitive performance, which have previously been derived by factor analysis of CDR subtests. Levels of terpenoids (bilobalide, ginkgolide A and ginkgolide B) were concomitantly assessed in plasma samples taken pre-dose and at 3 and 6.5 h post-dose.In keeping with previous research utilising the same methodology, 120 mg of GBE was not associated with markedly improved performance on the primary outcomes. However, administration of GBE complexed with phosphatidylserine resulted both in improved secondary memory performance and significantly increased speed of memory task performance across all of the post-dose testing sessions. Enhancement following GBE complexed with phosphatidylcholine was restricted to a modest improvement in secondary memory performance which was restricted to one post-dose time point. All three treatments were associated with improved calmness. There were no significant differences in post-dose levels of terpenoids between the Ginkgo containing treatments, although this latter finding may be attributable to methodological factors. Complexation with phosphatidylserine appears to potentiate the cognitive effects associated with a low dose of GBE. Further research is required to identify whether this effect is due to the complexation of the extracts, their mere combination, or the separate psychopharmacological actions of the two extracts.


Assuntos
Cognição/efeitos dos fármacos , Ginkgo biloba/química , Fosfatidilserinas/farmacologia , Adulto , Afeto/efeitos dos fármacos , Atenção/efeitos dos fármacos , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Testes Neuropsicológicos , Fosfatidilserinas/farmacocinética , Extratos Vegetais/farmacocinética , Extratos Vegetais/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Terpenos/sangue
4.
J Mass Spectrom ; 42(3): 288-92, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17177235

RESUMO

The identification of hemoglobin (Hb) variants is usually performed by means of different analytical steps and methodologies. Phenotypic methods, such as gel electrophoresis and high performance liquid chromatography, are used to detect the different electrophoretic or chromatographic behaviors of hemoglobin variants in comparison to HbA0 used as a control. These data often need to be combined with mass spectrometry analyses of intact globins and their tryptic peptide mixtures. As an alternative to a 'step-by-step' procedure, we have developed a 'single step' approach for the identification of Hb variants present in biological samples. This is based on the microHPLC-ESI-MS/MS analysis of the peptide mixture generated by a tryptic digestion of diluted Hb samples and an in-house new database containing solely the variant tryptic peptide of known human Hb variants. The experimental results (full MS and MS/MS spectra) are correlated with theoretical mass spectra generated from our in-house-built variant peptide database (Hbp) using the SEQUEST algorithm. Simple preparation of samples and an automated identification of the variant peptide are the main characteristics of this approach, making it an attractive method for the detection of Hb variants at the routine clinical level. We have analyzed 16 different samples, each containing a different known variant of hemoglobin.


Assuntos
Cromatografia Líquida/métodos , Bases de Dados de Proteínas , Hemoglobinas/química , Hemoglobinas/genética , Peptídeos/química , Análise de Sequência de Proteína/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Sequência de Aminoácidos , Variação Genética , Dados de Sequência Molecular , Mapeamento de Peptídeos/métodos , Alinhamento de Sequência/métodos
5.
J Mass Spectrom ; 40(12): 1546-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16320299

RESUMO

Boron neutron capture therapy (BNCT) is a promising binary treatment for cancer. BNCT is based on the ability of the nonradioactive isotope (10)B to capture, with a very high probability, thermal neutrons. This nuclear reaction results in two particles (an alpha and a lithium nucleus). The particles have a high biological effectiveness, which is limited in tissue to approximately the diameter of one cell. If the reaction can be limited to a tumor cell, the physical characteristic opens up the possibility to selectively destroy cancer cells, while sparing the surrounding healthy tissue. Quality control of (10)B-containing compounds and their distribution at present are very important, and different analytical methods have been developed, such as time-of-flight secondary ion mass spectrometry (TOF-SIMS), electron energy loss spectrometry (EELS), prompt gamma analysis and inductively coupled plasma-optical emission spectrometry (ICP-OES). These methods allow the analyses of (10)B, but it is not possible to characterize the specific molecular compounds containing (10)B. For this reason, we propose a fast and quantitative method that permits the determination of closo-undecahydro-1-mercaptododecaborate (BSH) and (10)boron-phenylalanine (BPA) and their eventual metabolites. In particular, (10)B-containing compounds are detected by means of flow-injection electrospray tandem mass spectrometry (FI/ESI-MS/MS). This approach allows the identification of Boron compounds, BSH and BPA, using tandem mass spectrometry, and quantitative analysis is also possible (c.v. +/-4.7%; n = 5; linear range 10-10,000 ng/ml). Furthermore, (10)B-containing compounds were detected in actual biological sample (urine and plasma, diluted 10,000- and 1,000-fold, respectively) injecting a small volume (1 microl) of diluted samples.


Assuntos
Boroidretos/análise , Compostos de Boro/análise , Terapia por Captura de Nêutron de Boro/métodos , Fenilalanina/análogos & derivados , Espectrometria de Massas por Ionização por Electrospray/métodos , Compostos de Sulfidrila/análise , Adulto , Boroidretos/farmacocinética , Boro , Compostos de Boro/farmacocinética , Compostos de Boro/urina , Ensaios Clínicos Fase I como Assunto , Humanos , Isótopos , Pessoa de Meia-Idade , Fenilalanina/análise , Fenilalanina/farmacocinética , Fenilalanina/urina , Compostos de Sulfidrila/farmacocinética
6.
Cell Mol Life Sci ; 62(13): 1502-13, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15971002

RESUMO

Recent reports describe successful treatment using copper chelation therapy in neurodegenerative animal models. However, the success claimed for chelation therapy in neurodegenerative diseases is still rather controversial. To acquire new information on copper metabolism/homeostasis, we utilized cuprizone, a very sensitive and selective copper-chelating agent with well-known neurotoxic properties, as a relevant chemical model in mice. Upon cuprizone treatment, mice developed a pronounced astrocytosis, with brain oedema and spongiosis characterised by vacuolisations of the neuropil predominantly in the white matter. In addition, cuprizone treatment severely altered copper and zinc homeostasis in the central nervous system (CNS) as well as in all other tissues examined, with increasing metal ion concentrations particularly in the CNS. Concomitant with this increase in the Cu and Zn concentration in the brain, metallothionein-I and -II were also highly immunoreactive in astrocyte, consistent with the astrocytosis and demyelination observed in our and other laboratories.


Assuntos
Encéfalo/metabolismo , Quelantes/farmacologia , Cobre/metabolismo , Cuprizona/farmacologia , Zinco/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Quelantes/farmacocinética , Cobre/análise , Cobre/urina , Cuprizona/farmacocinética , Imuno-Histoquímica , Intestino Grosso/química , Intestino Delgado/química , Ferro/análise , Ferro/metabolismo , Ferro/urina , Rim/química , Fígado/química , Pulmão/química , Masculino , Metalotioneína/análise , Metalotioneína/metabolismo , Metalotioneína/urina , Camundongos , Camundongos Endogâmicos , Miocárdio/química , Baço/química , Estômago/química , Distribuição Tecidual , Zinco/análise , Zinco/urina
7.
J Pharm Biomed Anal ; 32(4-5): 657-61, 2003 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-12899955

RESUMO

8-Hydroxy-2'-deoxyguanosine (8OHdG) is regarded as an important biomarker of oxidative DNA damage and it may be estimated by using different techniques in various biological matrices, most notably DNA and urine. In the case of DNA, artifactual oxidation may take place during the isolation of DNA, its hydrolysis and possible derivatization (as for GC-MS), invalidating the measurement of 8OHdG. Therefore, the direct analysis of 8OHdG excreted into urine was preferred. Interferences from the urine matrix were excluded by applying LC-APCI-MS/MS in the multiple reaction monitoring (MRM) mode. The abundant fragment ion at m/z 168 arising from 8OHdG was monitored in the urine sample of volunteers supplemented with tomato concentrate for different times. The procedure allowed the detection of levels of 8OHdG as low as 1 ng/ml in urine sample.


Assuntos
Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , 8-Hidroxi-2'-Desoxiguanosina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Desoxiguanosina/química , Humanos , Espectrometria de Massas/métodos
8.
Ann Nutr Metab ; 47(2): 64-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12652057

RESUMO

BACKGROUND/AIMS: Besides antioxidant vitamins and minerals, fruits and vegetables contain flavonoids and related phenolics. The biological activities of these polyphenols have become well known in recent years evidencing their beneficial effects on human health. In this context, the characterization of the flavonoids present in tomatoes is of great interest. Thus the polyphenol pattern (including flavonols, flavanones and cinnamate derivatives), lycopene and beta-carotene concentrations and the total antioxidant activity (TAA) of the phenolic fraction from different tomato lines and cultivars have been determined. METHODS: The characterization was obtained by means of spectrophotometry and HPLC analyses. RESULTS: Mean values for single flavonoids were 0.68 +/- 0.16 for naringenin, 0.74 +/- 0.12 for rutin and 0.32 +/- 0.06 for a rutin-pentoside. Mean total polyphenol content was 13.15 +/- 1.15 mg/100 g and mean TAA value was 1.3 +/- 0.10 mmol/g. The obtained TAA values resulted in good accordance with the total polyphenol content (R(2) = 0.7928). The main phenolic acids were chlorogenic (mean +/- SE 0.20 +/- 0.03) and caffeic acid (mean +/- SE 0.03 +/- 0.01). Mean levels of lycopene and beta-carotene were 5.38 +/- 0.90 and 1.18 +/- 0.40 mg/100 g, respectively. CONCLUSIONS: Almost all the lines characterised by low carotenoid content produce high levels of polyphenols, and consequently have the most powerful antioxidant potential.


Assuntos
Antioxidantes/análise , Fenóis/análise , Polímeros/análise , Solanum lycopersicum/química , Solanum lycopersicum/genética , Antioxidantes/metabolismo , Carotenoides/análise , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonóis , Licopeno , Espectrofotometria/métodos , beta Caroteno/análise , beta Caroteno/metabolismo
9.
Rapid Commun Mass Spectrom ; 15(12): 929-34, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11400198

RESUMO

Liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-ITMS) was applied to evaluate the levels of ginkgolides A and B and bilobalide in plasma of volunteers after administration of Ginkgo biloba extracts in free (Ginkgoselect) or phospholipid complex (Ginkgoselect Phytosome) forms, providing 9.6 mg of total terpene lactones. The maximum plasma concentrations, C(max), of total ginkgolides A, B and bilobalide were 85.0 and 181.8 microg/mL for Ginkgoselect and Ginkgoselect Phytosome, respectively. The C(max) values were reached at 120 min for the free form and at 180--240 min for the phospholipid complex form. In both cases, the mean elimination half-life of each terpene lactone was in the range 120--180 min. Due to its sensitivity (about 1 ng/mL) and specificity, LC/APCI-ITMS proved to be a very powerful tool for pharmacokinetic studies of these phytochemicals.


Assuntos
Cromatografia Líquida/métodos , Ciclopentanos/sangue , Diterpenos , Furanos/sangue , Ginkgo biloba , Lactonas/sangue , Espectrometria de Massas/métodos , Extratos Vegetais/farmacocinética , Plantas Medicinais , Adulto , Área Sob a Curva , Privação de Alimentos , Ginkgolídeos , Meia-Vida , Humanos , Masculino
11.
Infect Immun ; 69(5): 3442-6, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11292772

RESUMO

The gene slpA, encoding the S-layer precursor protein in the virulent Clostridium difficile strains C253 and 79--685, was identified. The precursor protein carries a C-terminal highly conserved anchoring domain, similar to the one found in the Cwp66 adhesin (previously characterized in strain 79--685), an SLH domain, and a variable N-terminal domain mediating cell adherence. The genes encoding the S-layer precursor proteins and the Cwp66 adhesin are present in a genetic locus carrying 17 open reading frames, 11 of which encode a similar two-domain architecture, likely to include surface-anchored proteins.


Assuntos
Proteínas de Bactérias/genética , Clostridioides difficile/genética , Sequência de Aminoácidos , Proteínas de Bactérias/química , Clostridioides difficile/química , Dados de Sequência Molecular , Família Multigênica , Fases de Leitura Aberta , Homologia de Sequência
12.
J Pharm Biomed Anal ; 23(1): 61-8, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10898155

RESUMO

Extracts of selected medicinal plants were examined by electrospray mass spectrometry (ESI-MS). This technique allowed identification of the main components of each extract, thereby providing a typical finger-print of the examined plants. More specifically, anthocyanins (Vaccinium myrtillus), isoflavones (Glycine max, soybean), flavonol-glycosides and terpenes (Ginkgo biloba), triterpenes (Centella asiatica), caffeoyl-quinic acids (Cynara scolymus, artichoke), ginsenosides (Panax ginseng), catechins (Camellia sinensis, green tea) and flavones and flavanones (Propolis) were detected rapidly at levels in the range of 0.1-1 microg/ml, using 0.2-1 mg/ml of each medicinal plant extract.


Assuntos
Extratos Vegetais/química , Plantas Medicinais/química , Espectrometria de Massas por Ionização por Electrospray
14.
Rapid Commun Mass Spectrom ; 14(4): 243-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10669883

RESUMO

Oligonucleotides have become widely used tools in molecular biology and molecular diagnostics. Their parallel synthesis in large numbers and the increasing interest in microarray technology has raised the requirement for fast and informative analytical tools for their quality control. A direct injection electrospray ionization mass spectrometry (ESI-MS) technique based on the use of aqueous 2-propanol as running eluent, and spermidine (or triethylamine) as DNA modifiers, has been applied to analyze a large set of samples (about 200 synthetic oligonucleotides) ranging from 5 to 15 kDa (17-51mers) with good results in terms of sensitivity, suppression of sodium adduct formation, and speed of analysis. Copyright 2000 John Wiley & Sons, Ltd.

15.
Rapid Commun Mass Spectrom ; 14(2): 95-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10623936

RESUMO

Hypericum perforatum L. (St. John's Wort) is a widely distributed herbaceous perennial plant which has been well known as a medicinal plant since antiquity. In recent years, H. perforatum has received increasing attention for the treatment of depression and other neuralgic disorders. The main constituents of H. perforatum extract include flavonoids, naphthodianthrones, phloroglucinols, essential oils and xanthones. The present work reports the analysis of naphthodianthrones and phloroglucinols in H. perforatum extracts by means of high performance liquid chromatography (HPLC) coupled simultaneously to a diode array detector (DAD) and electrospray mass spectrometry (ESI-MS). Hypericin, pseudohypericin, hyperforin and adhyperforin were separated and identified on the base of their on-line UV and mass spectra. Quantitative analysis of hypericin derivatives in different extracts of H. perforatum using DAD and MS detectors was performed. In addition, direct infusion ESI-MS of H. perforatum extracts was applied to obtain rapid mass fingerprints of constituents present in the sample.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hypericum/química , Espectrometria de Massas/métodos , Extratos Vegetais/química , Plantas Medicinais
16.
J Mass Spectrom ; 34(12): 1361-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10587633

RESUMO

Standardized extracts of Ginkgo biloba leaves are mainly used in the treatment of peripheral and celebral circulation disorders, and also as a remedy against asthma, coughs, bladder inflammation, blenorrhagia and alcohol abuse. The leaf extracts contain biflavones, flavonol glycosides and terpene lactones. This paper reports a method based on liquid chromatography coupled with electrospray mass spectrometry for the analysis of terpenoids in G. biloba extracts. This method allows the rapid isocratic separation of underivatized ginkgolides (GA, GB, GC and GJ) and bilobalide at very low levels (10 pg on the column) and their quantitative detection by external standardization with relative standard deviations of 3 and 5% for intra- and inter-day analyses, respectively.


Assuntos
Diterpenos , Medicamentos de Ervas Chinesas/química , Ginkgo biloba/química , Plantas Medicinais , Terpenos/química , Cromatografia Líquida , Ciclopentanos/análise , Ciclopentanos/química , Ciclopentanos/normas , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Furanos/análise , Furanos/química , Furanos/normas , Ginkgolídeos , Humanos , Lactonas/análise , Lactonas/química , Lactonas/normas , Espectrometria de Massas , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/normas , Padrões de Referência , Terpenos/análise , Terpenos/normas
18.
Rapid Commun Mass Spectrom ; 13(10): 924-31, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10353226

RESUMO

Flavonoids continue to attract wide attention as possible very useful agents for combating free radical pathologies, i.e. the pathological states associated with free radical overproduction. Commonly used methods for the analysis of plant flavonoids include high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). On the other hand, the soft-ionization approach based on electrospray ionization (ESI-MS) permits highly selective analysis of complex matrices. In this work, we examined firstly the ESI-MS behaviour of representative aglycones and glycosides of flavonols, flavones and isoflavones with the aim of suggesting a possible relationship between structure and mass spectra. Using HPLC coupled to a diode array detector (DAD) for on-line UV spectra acquisition, and in parallel to ESI-MS for mass spectra (LC/DAD-ESI-MS), we have developed methodology to observe flavonols directly in tomato puree extract. In this way, it has been possible to detect intact flavonol glycosides in tomato extracts and to characterize a flavonol trisaccharide. For the first time, using LC/ESI-MS, it has been possible to detect intact flavonol glycosides in plasma of healthy volunteers and to provide further evidence on the absorption of flavonoid glycosides after consumption of common vegetables like tomatoes.


Assuntos
Flavonoides/sangue , Glicosídeos/sangue , Solanum lycopersicum/química , Calibragem , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Glicosídeos/química , Humanos , Espectrometria de Massas , Rutina/análise , Espectrofotometria Ultravioleta
19.
Rapid Commun Mass Spectrom ; 13(8): 695-703, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10343411

RESUMO

Surface layers (S-layers) are regularly ordered protein subunits found as the outermost cell envelope component of many bacteria. Most S-layers are composed of a single protein or glycoprotein species with a molecular weight varying between 40 and 200 kDa. Clostridium difficile is the most common cause of antibiotic associated diarrhea (AAD) and pseudomembranous colitis (PMC) in humans. Detection of the S-layer in some C. difficile strains, and preliminary characterization of two glycoproteins, P36 and P47, involved in the composition of the S-layer of one of these strains (C. difficile C253), led us to investigate the most appropriate conditions for purification and chemical characterization of these proteins. This work describes the results obtained when liquid chromatography (LC) coupled to mass spectrometry (MS) using electrospray ionization was applied to the analysis of C. difficile S-layer proteins (SLPs). In this way the molecular weights of the two SLP components, P36 and P47, were detected to be 34,258 +/- 2 and 39,545 +/- 3 Da, respectively. These data deviate from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results by 1.85 and 7.5 kDa. To confirm the LC-MS results, an alternative molecular weight analysis was performed: the two S-layer proteins were isolated by semipreparative high performance liquid chromatography (HPLC), concentrated, and analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF). The two SLP subunits were digested with protease V8, and the peptide maps were determined by LC-MS using a C18 column. Finally, preliminary results about peptide glycosylation were obtained.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Clostridioides difficile/química , Parede Celular/química , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Glicoproteínas/química , Hidrólise , Espectrometria de Massas , Peso Molecular , Fragmentos de Peptídeos/química , Mapeamento de Peptídeos
20.
Oncogene ; 17(10): 1313-9, 1998 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-9771975

RESUMO

As a consequence of a reciprocal translocation t(17;22)(q22;q13) and of supernumerary ring chromosomes derived from the t(17;22), a fusion between the platelet-derived growth factor b-chain (PDGF, c-sis proto-oncogene) and the collagen type 1A1 (COL1A1) genes has been recently described in dermatofibrosarcoma protuberans (DP), an infiltrating skin tumor (Simon et al., 1997). Although PDGFB has been implicated in transforming processes via autocrine and paracrine pathways, by the activation of the cognate receptor, no direct evidence of its involvement in neoplastic transformation of human tumours has been so far provided. In this report, we have tested the DNA from four DPs in the classical DNA transfection assay onto NIH3T3 fibroblast cell line. All the DNAs induced the formation of transformed foci in the transfected cultures whose derived cell lines were shown to contain a fused sequence comprising the human COL1A1 and PDGF genes. The relative breakpoint regions have been sequenced revealing that this gene fusion deleted exon 1 of PDGF and released the growth factor from its normal regulation. All the biochemical and biological assays were consistent with the model of an autocrine mechanism for NIH3T3 transformation by the human rearranged PDGFB gene involving the activation of the endogenous PDGF receptor.


Assuntos
Fusão Gênica Artificial , Colágeno/genética , Dermatofibrossarcoma/genética , Fator de Crescimento Derivado de Plaquetas/genética , Transformação Genética , Células 3T3/patologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular Transformada , Humanos , Camundongos , Camundongos Nus , Mitógenos/metabolismo , Dados de Sequência Molecular , Proto-Oncogene Mas , Suramina/farmacologia , Translocação Genética
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