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1.
Forensic Sci Int ; 335: 111281, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35429777

RESUMO

We discuss how different accelerator-based techniques can be employed synergistically as a powerful analytical tool for forensic studies of foodstuff. Brazilian and Jamaican coffees were chosen as a showcase due to its popularity and potential risk of adulteration and/or falsification. Comprehensive characterization of major and trace elements, age since production and compound contents were achieved using different techniques, including PIXE (Particle-Induced X-ray Emission), FTIR (Fourier Transform Infrared), and AMS-14C (Accelerator Mass Spectrometry - Radiocarbon Analysis). While PIXE provides information on the elements present in the samples, FTIR probes the types of compounds through their vibrational spectra. Finally, AMS-14C is capable of dating organic samples regarding their harvesting time. Five different laboratories from research institutions around the world took part in the experiments. The integration of the results obtained with different techniques provided multifaceted perspectives on the coffee under study, thus allowing a direct assessment of the material for forensic purposes such as authentication, determination of provenance, and combat counterfeiting.


Assuntos
Café , Oligoelementos , Brasil , Contaminação de Medicamentos , Espectrometria de Massas/métodos
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 171: 280-286, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27541800

RESUMO

Lactose and saccharose have the same molecular formula; however, the arrangement of their atoms is different. A major difference between lactose and saccharose with regard to digestion and processing is that it is not uncommon for individuals to be lactose intolerant (around two thirds of the population has a limited ability to digest lactose after infancy), but it is rather unlikely to be saccharose intolerant. The pharmaceutical industry uses lactose and saccharose as inactive ingredients of drugs to help form tablets because of their excellent compressibility properties. Some patients with severe lactose intolerance may experience symptoms of many allergic reactions after taking medicine that contains this substance. People who are specifically "allergic" to lactose (not just lactose intolerant) should not use tablets containing this ingredient. Fourier Transform Infrared (FTIR) spectroscopy has a unique chemical fingerprinting capability and plays a significant important role in the identification and characterization of analyzed samples and hence has been widely used in pharmaceutical science. However, a typical FTIR spectrum collected from tablets contains a myriad of valuable information hidden in a family of tiny peaks. Powerful multivariate spectral data processing can transform FTIR spectroscopy into an ideal tool for high volume, rapid screening and characterization of even minor tablet components. In this paper a method for distinction between FTIR spectra collected for tablets with or without lactose is presented. The results seem to indicate that the success of identifying one component in FTIR spectra collected for pharmaceutical composition (that is tablet) is largely dependent on the choice of the chemometric technique applied.


Assuntos
Lactose/análise , Preparações Farmacêuticas/química , Análise por Conglomerados , Furagina/química , Análise de Componente Principal , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/análise
3.
Analyst ; 140(7): 2156-63, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25574521

RESUMO

The pituitary gland is a small but vital organ in the human body. It is located at the base of the brain and is often described as the master gland due to its multiple functions. The pituitary gland secretes and stores hormones, such as the thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), growth hormone (hGH), prolactin, gonadotropins, and luteinizing hormones, as well as the antidiuretic hormone (ADH). A proper diagnosis of pituitary disorders is of utmost importance as this organ participates in regulating a variety of body functions. Typical histopathological analysis provides much valuable information, but it gives no insight into the biochemical background of the changes that occur within the gland. One approach that could be used to evaluate the biochemistry of tissue sections obtained from pituitary disorders is Fourier Transform Infra-Red (FTIR) spectromicroscopy. In order to collect diagnostically valuable information large areas of tissue must be investigated. This work focuses on obtaining a unique and representative FTIR spectrum characteristic of one type of cell architecture within a sample. The idea presented is based on using hierarchical cluster analysis (HCA) for data evaluation to search for uniform patterns within samples from the perspective of FTIR spectra. The results obtained demonstrate that FTIR spectromicroscopy, combined with proper statistical evaluation, can be treated as a complementary method for histopathological analysis and ipso facto can increase the sensitivity and specificity for detecting various disorders not only for the pituitary gland, but also for other human tissues.


Assuntos
Hipófise/citologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise por Conglomerados , Humanos , Imagem Óptica , Hipófise/química
4.
Anal Bioanal Chem ; 406(17): 4173-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24752694

RESUMO

Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work was to determine whether Fourier transform infrared (FTIR) spectromicroscopy could be used to detect contamination in a fingerprint which was dusted with powder (a technique already recognized as an effective and reliable method for developing latent fingerprints) and subsequently lifted off with adhesive tape. Explosive materials (pentaerythritol tetranitrate, C-4, TNT) and noncontrolled substances (sugar, aspirin) were used to prepare contaminated fingerprints on various substrates. Freshly deposited fingermarks with powders which were lifted off with adhesive tapes (provided by Singapore Police Force) were analyzed using a Bruker Hyperion 2000 microscope at the ISMI beamline (Singapore Synchrotron Light Source) with an attenuated total reflection objective. FTIR spectroscopy is a nondestructive technique which requires almost no sample preparation. Further, the fingerprint under analysis remains in pristine condition, allowing subsequent analysis if necessary. All analyzed substances were successfully distinguished using their FTIR spectra in powdered and lifted fingerprints. This method has the potential to significantly impact forensic science by greatly enhancing the information that can be obtained from the study of fingerprints.

5.
Analyst ; 137(15): 3459-65, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22693711

RESUMO

Synchrotron radiation-based Fourier transform infra-red (SR-FTIR) micro-imaging has been developed as a rapid, direct and non-destructive technique. This method, taking advantage of the high brightness and small effective source size of synchrotron light, is capable of exploring the molecular chemistry within the microstructures of microscopic particles without their destruction at high spatial resolutions. This is in contrast to traditional "wet" chemical methods, which, during processing for analysis, often caused destruction of the original samples. In the present study, we demonstrate the potential of SR-FTIR micro-imaging as an effective way to accurately identify microscopic particles deposited within latent fingerprints. These particles are present from residual amounts of materials left on a person's fingers after handling such materials. Fingerprints contaminated with various types of powders, creams, medications and high explosive materials (3-nitrooxy-2,2-bis(nitrooxymethyl)propyl nitrate (PETN), 1,3,5-trinitro-1,3,5-triazinane (RDX), 2-methyl-1,3,5-trinitrobenzene (TNT)) deposited on various - daily used - substrates have been analysed herein without any further sample preparation. A non-destructive method for the transfer of contaminated fingerprints from hard-to-reach areas of the substrates to the place of analysis is also presented. This method could have a significant impact on forensic science and could dramatically enhance the amount of information that can be obtained from the study of fingerprints.


Assuntos
Aspirina/análise , Dermatoglifia , Substâncias Explosivas/análise , Pós/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Síncrotrons , Carboidratos/análise , Humanos , Tamanho da Partícula , Triazinas/análise , Trinitrotolueno/análise
6.
Opt Express ; 20(3): 2004-14, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22330441

RESUMO

This work primarily aims to fabricate and use two photon polymerization (2PP) microstructures capable of being optically manipulated into any arbitrary orientation. We have integrated optical waveguides into the structures and therefore have freestanding waveguides, which can be positioned anywhere in the sample at any orientation using optical traps. One of the key aspects to the work is the change in direction of the incident plane wave, and the marked increase in the numerical aperture demonstrated. Hence, the optically steered waveguide can tap from a relatively broader beam and then generate a more tightly confined light at its tip. The paper contains both simulation, related to the propagation of light through the waveguide, and experimental demonstrations using our BioPhotonics Workstation. In a broader context, this work shows that optically trapped microfabricated structures can potentially help bridge the diffraction barrier. This structure-mediated paradigm may be carried forward to open new possibilities for exploiting beams from far-field optics down to the subwavelength domain.


Assuntos
Desenho Assistido por Computador , Modelos Teóricos , Impressão Molecular/instrumentação , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
7.
J Biol Inorg Chem ; 16(8): 1187-96, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21706339

RESUMO

The prostate gland is the most common site of neoplastic disorders in men. The pathogenesis of inflammatory cells, prostatic intraepithelial neoplasia (PIN) lesions, and prostate cancer is still under investigation. Inflammatory cells by producing free radicals are considered as major and universal contributors to cancerogenesis. PIN is regarded as a precursor lesion to prostate cancer or a marker signaling the vulnerability of the epithelium to neoplastic transformation [1]. Differentiation markers that are frequently changed in early invasive carcinoma are also changed in PIN lesions. In this study, prostate tissue samples obtained during surgical operation and classified as various disease states (inflammation, PIN lesions, and cancer) were examined. The samples were measured by means of microbeam synchrotron-radiation-induced X-ray emission (micro-SRIXE). Special attention was paid to examine the relationship between the earlier-mentioned disorders and changes in relative concentrations of S, K, Ca, Fe, Cu, and Zn. Applying the image-processing program ImageJ enabled us to select the areas of interest from two-dimensional maps of various prostate samples according to the histopathologist's evaluation. Detailed analysis of micro-SRIXE spectra based on multivariate methods shows significant differences between elemental concentrations in inflammatory cells, PIN lesions, and cancerous tissues, which confirms that this method can be used to distinguish various pathological states in prostate tissues. Information obtained in this way may provide better understanding of the biochemistry of unhealthy prostate tissues, thus opening the way to find new medicines/treatments to prevent or slow down some harmful intracellular processes.


Assuntos
Próstata/química , Neoplasia Prostática Intraepitelial/química , Neoplasias da Próstata/química , Espectrometria por Raios X/métodos , Oligoelementos/análise , Idoso , Humanos , Inflamação/metabolismo , Inflamação/patologia , Masculino , Análise Multivariada , Próstata/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Síncrotrons
8.
J Biol Inorg Chem ; 15(7): 1147-55, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20499115

RESUMO

The causes of prostate cancer are still obscure but some evidence indicates that there is a close connection between several trace elements and processes which may lead to malignant cells. In our study the microbeam synchrotron radiation X-ray fluorescence emission (micro-SRIXE) technique was applied for quantitative analysis of selected elements. For the first time, we correlate the concentrations of Mn, Fe, Cu, and Zn with the clinical stage of the prostate cancer at the time of operation (described by Gleason grade). Serial sections of prostate tissues were collected from patients undergoing radical prostatectomy. One section, stained with hematoxylin and eosin, was prepared for histopathological analysis; a second, adjacent unstained section was used in micro-SRIXE experiments. All experiments were performed at beamline L at HASYLAB, DESY, Germany. Our results seem to be valuable in light of the determination of the changes in the concentrations of trace elements as a potential diagnostic marker and their etiological involvement in the different stages of prostate diseases.


Assuntos
Próstata/química , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Oligoelementos/análise , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Próstata/patologia , Espectrometria por Raios X/métodos , Síncrotrons
9.
Anal Chem ; 82(7): 3038-44, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20218700

RESUMO

Fourier transform-infrared (FT-IR) spectroscopy has gained considerable attention among the forensic scientists because it shows high sensitivity and selectivity and offers near real time detection of analyzed samples. However, the amount of obtained information due to complexity of the measured spectra forces the use of additional data processing. Application of the multivariate statistical techniques for the analysis of the FT-IR data seems to be necessary in order to enable feature extraction, proper evaluation, and identification of obtained spectra. In this article, an attempt to develop a feasible procedure for characterization of spectroscopic signatures of the explosive materials in the remnants after explosion has been made. All spectra were derived after analysis of samples from debris after especially prepared and performed blasts with the use of three various highly explosive materials: C-4, 2,4,6-trinitrotoluene (TNT), and pentaerythritol tetranitrate (PETN). Two well-known multivariate statistical methods, hierarchical cluster analysis (HCA) and principal component analysis (PCA), were tested in order to classify the samples into separate classes using a broad wavelength data range (4000-600 cm(-1)) on collected spectra sets. After many trials it seems that PCA is the best choice for the mentioned earlier tasks. It was found that only three principal components carry over 99.6% of variance within the sample set. The results show that FT-IR spectroscopy in combination with multivariate methods is well-suited for identification and differentiation purposes even in quite large data sets, and for that reason forensic laboratories could employ these methods for rapid screening analysis.

10.
AJNR Am J Neuroradiol ; 29(2): 319-25, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17974604

RESUMO

BACKGROUND AND PURPOSE: Evidence is mounting that spinal cord atrophy significantly correlates with disability in patients with multiple sclerosis (MS). The purpose of this work was to validate 3 different measures for the measurement of cervical cord atrophy on high-resolution MR imaging in patients with MS and in normal control subjects (NCs). We also wanted to evaluate the relationship between cervical cord atrophy and clinical disability in the presence of other conventional and nonconventional brain MR imaging metrics by using a unique additive variance regression model. MATERIALS AND METHODS: We studied 66 MS patients (age, 41.2 +/- 12.4 years; disease duration, 11.8 +/- 10.7 years; Expanded Disability Status Scale, 3.1 +/- 2.1) and 19 NCs (age, 30.4 +/- 12.0 years). Disease course was relapsing-remitting (34), secondary-progressive (14), primary-progressive (7), and clinically isolated syndrome (11). The cervical cord absolute volume (CCAV) in cubic millimeters and 2 normalized cervical cord measures were calculated as follows: cervical cord fraction (CCF) = CCAV/thecal sac absolute volume, and cervical cord to intracranial volume (ICV) fraction (CCAV/ICV). Cervical and brain lesion volume measures, brain parenchyma fraction (BPF), and mean diffusivity were also calculated. RESULTS: CCAV (P < .0001) and CCF (P = .007) showed the largest differences between NCs and MS patients and between different disease subtypes. In regression analysis predicting disability, CCAV was retained first (R(2) = 0.498; P < .0001) followed by BPF (R(2) = 0.08; P = .08). Only 8% of the variance in disability was explained by brain MR imaging measures when coadjusted for the amount of cervical cord atrophy. CONCLUSIONS: 3D CCAV measurement showed the largest differences between NCs and MS patients and between different disease subtypes. Cervical cord atrophy measurement provides valuable additional information related to disability that is not obtainable from brain MR imaging metrics.


Assuntos
Vértebras Cervicais/patologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico , Medula Espinal/patologia , Adulto , Atrofia/patologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
J Physiol Pharmacol ; 56 Suppl 4: 99-105, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16204782

RESUMO

The aim of the study was to evaluate the quality of life and its changes in patients with idiopathic pulmonary fibrosis (IPF), waiting for lung transplantation. Sixteen IPF patients, who qualified for lung transplantation, and 14 chronic obstructive pulmonary disease (COPD) patients on long term oxygen therapy, taken as a reference group, were assessed. The quality of life was estimated twice, using an SF-36-questionnaire, at the time of qualification for lung transplantation and 12 months later. The IPF and reference patients had similarly profound disturbances in lung function and arterial blood gas content. The IPF patients had a statistically greater score in their physical functioning (PF; 45 vs. 18), the role of limitations due to physical problems (RP; 43 vs. 11), social functioning (SF; 58 vs. 30), and the role of emotional limitations in everyday life (RE; 65 vs. 12) than the reference ones. After a year's observation, there were no differences in SF-36 questionnaire results, except for the role of limitations due to physical problems (RP). A correlation was noted between spirometry and blood gas results and SF-36 questionnaire results in IPF patients qualified for lung transplantation. There was a positive correlation between the partial pressure of oxygen (PaO(2)), on one side, and mental and general health, on the other. There also were positive correlations between FEV1 and SF and FEV1 and the level of bodily pain (BP). We conclude that the SF-36 questionnaire is a sensitive tool to assess the quality of life in IPF patients qualified for lung transplantation. The information gained can help assess the severity of the disease, clinical symptoms, and functional impairment in these patients.


Assuntos
Efeitos Psicossociais da Doença , Transplante de Pulmão , Fibrose Pulmonar/psicologia , Fibrose Pulmonar/cirurgia , Qualidade de Vida , Listas de Espera , Atividades Cotidianas , Gasometria , Estudos de Casos e Controles , Emoções , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fibrose Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Comportamento Social , Espirometria , Inquéritos e Questionários , Fatores de Tempo
12.
Biochim Biophys Acta ; 1740(2): 222-39, 2005 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-15949690

RESUMO

Endothelial cells play an important role in angiogenesis (formation of new vessels from preexisting ones), which is essential for organogenesis, tissue remodeling but also inflammatory response, carcinogenesis in all periods of our life. Beta-carotene (BC) in non-toxic concentrations (up to 3 microM) had no detectable effect on HUVECs (human umbilical vein endothelial cells) proliferation or apoptosis, despite significant changes of the expression patterns of pro- and anti-apoptotic genes. However beta-carotene did not change the tubulogenic activity of HUVEC in the in vitro angiogenesis model, it potently accelerated the bFGF-induced development of microcapillaries, as well as the migration of endothelial cells, in matrigel plug injected subcutaneously to mice. Potent activation of endothelial cell migration in the in vitro model of chemotaxis was also observed. According to the microarray data, genes involved in cell/cell and cell/matrix adhesion, matrix reorganization, activation of chemotaxis, the G-protein regulated intracellular signaling as well as genes involved in the rapid remodeling of protein cytoskeleton were the most affected by BC in HUVEC. We conclude that beta-carotene in the physiological concentration range stimulates early steps of angiogenesis by the activation of cellular migration as well as matrix reorganization and decrease of cell adhesion.


Assuntos
Indutores da Angiogênese/farmacologia , Quimiotaxia/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , beta Caroteno/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Ácido Araquidônico/farmacologia , Proliferação de Células , Quimiotaxia/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Análise em Microsséries , Microtúbulos/genética , Reação em Cadeia da Polimerase
14.
Proc Natl Acad Sci U S A ; 97(12): 6487-92, 2000 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-10829075

RESUMO

Triacylglycerol (TAG) is known to be synthesized in a reaction that uses acyl-CoA as acyl donor and diacylglycerol (DAG) as acceptor, and which is catalyzed by the enzyme acyl-CoA:diacylglycerol acyltransferase. We have found that some plants and yeast also have an acyl-CoA-independent mechanism for TAG synthesis, which uses phospholipids as acyl donors and DAG as acceptor. This reaction is catalyzed by an enzyme that we call phospholipid:diacylglycerol acyltransferase, or PDAT. PDAT was characterized in microsomal preparations from three different oil seeds: sunflower, castor bean, and Crepis palaestina. We found that the specificity of the enzyme for the acyl group in the phospholipid varies between these species. Thus, C. palaestina PDAT preferentially incorporates vernoloyl groups into TAG, whereas PDAT from castor bean incorporates both ricinoleoyl and vernoloyl groups. We further found that PDAT activity also is present in yeast microsomes. The substrate specificity of this PDAT depends on the head group of the acyl donor, the acyl group transferred, and the acyl chains of the acceptor DAG. The gene encoding the enzyme was identified. The encoded PDAT protein is related to lecithin:cholesterol acyltransferase, which catalyzes the acyl-CoA-independent synthesis of cholesterol esters. However, budding yeast PDAT and its relatives in fission yeast and Arabidopsis form a distinct branch within this protein superfamily, indicating that a separate PDAT enzyme arose at an early point in evolution.


Assuntos
Aciltransferases/metabolismo , Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Triglicerídeos/biossíntese , Acil Coenzima A/fisiologia , Aciltransferases/genética , Catálise , Diacilglicerol O-Aciltransferase , Microssomos/metabolismo , Esterol O-Aciltransferase/metabolismo , Especificidade por Substrato
15.
Biochem Soc Trans ; 28(6): 703-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171177

RESUMO

We have characterized three CoA-independent types of enzyme, phospholipases, phospholipid:diacylglycerol acyltransferases (PDATs) and cholinephosphotransferases, responsible for the removal of unusual fatty acids from phosphatidylcholine (PC) in microsomal preparations from developing oil seeds. The metabolism of sn-2-[(14)C]acyl-PC was monitored in microsomal preparations from various oilseeds having either medium-chain, acetylenic, epoxy or hydroxy fatty acids as their major fatty acids in the oil. The results indicate that PDAT plays a major role in removing ricinoleic acid and vernolic acid from phospholipids in Ricinus communis and Crepis palaestina seeds, respectively. However, vernolic, crepenynic and capric acids are primarily removed from phospholipids by phospholipases in Euphorbia lagascae, Crepis rubra and elm seeds, respectively. Further, we show that significant PDAT activity is also present in vegetative tissues of Arabidopsis thaliana.


Assuntos
Aciltransferases/metabolismo , Plantas/enzimologia , Triglicerídeos/biossíntese , Arabidopsis/enzimologia , Ricinus communis/enzimologia , Cinética , Microssomos/enzimologia , Fosfatidilcolinas/metabolismo , Fosfolipases/metabolismo , Plantas Tóxicas , Ricinus/enzimologia , Especificidade por Substrato
16.
Biochem Soc Trans ; 28(6): 700-2, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171176

RESUMO

The major route for the synthesis of triacylglycerol (TAG) in yeast as well as in all TAG-accumulating organisms has been suggested to occur via the acylation of diacylglycerol (DAG) by acyl-CoA:diacylglycerol acyltransferase (DAGAT). Genes encoding DAGAT have been identified in both plant and animal tissues. These genes show strong sequence similarities to genes encoding acyl-CoA:cholesterol acyltransferase (ACAT). So far no Saccharomyces cerevisiae DAGAT gene has been published; however, two ACAT-like genes, ARE1 and ARE2, are present in the yeast genome. Both these genes have been suggested to be involved in the synthesis of sterol esters. We have now shown that the ARE1 gene in yeast also is involved in the synthesis of TAG, whereas the ARE2 gene is more specifically involved in the synthesis of sterol esters.


Assuntos
Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Esterol O-Aciltransferase/genética , Triglicerídeos/metabolismo , Animais , Deleção de Genes , Genoma Fúngico , Genótipo , Metabolismo dos Lipídeos , Plantas/enzimologia , Esterol O-Aciltransferase/metabolismo
17.
Biochem Soc Trans ; 28(6): 705-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171178

RESUMO

Lipids, proteins and starch are the main storage products in oat seeds. As a first step in elucidating the regulatory mechanisms behind the deposition of these compounds, two different oat varieties, 'Freja' and 'Matilda', were analysed during kernel development. In both cultivars, the majority of the lipids accumulated at very early stage of development but Matilda accumulated about twice the amount of lipids compared to Freja. Accumulation of proteins and starch started also in the early stage of kernel development but, in contrast to lipids, continued over a considerably longer period. The high-oil variety Matilda also accumulated higher amounts of proteins than Freja. The starch content in Freja kernels was higher than in Matilda kernels and the difference was most pronounced during the early stage of development when oil synthesis was most active. Oleosin accumulation continued during the whole period of kernel development.


Assuntos
Avena/fisiologia , Metabolismo dos Lipídeos , Proteínas de Plantas/metabolismo , Sementes/fisiologia , Amido/metabolismo , Especificidade da Espécie
18.
Biochem Soc Trans ; 28(6): 777-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171205

RESUMO

Seedlings of wheat were grown for 24 h in control nutrient solution and in solutions containing haloxyfop, alloxydim, diquat or paraquat, and thereafter the roots were used for microsomal preparations. Phosphatidylcholine or diacylglycerol with various 1-(14)C-labelled fatty acids (oleic, linoleic, linolenic or ricinoleic acids) in position sn-2 were added to the prepared microsomes. After incubation for 2 h at 30 degrees C, the lipids were extracted and the distribution of radioactivity among lipid classes was determined. In the microsomal preparations of plants treated with diquat and paraquat, the amounts of fatty acids released were similar to the control, whereas they were 1.4-2 times higher in the microsomal preparation of plants treated with haloxyfop and alloxydim. Thus, the data indicate that graminicides could increase lipid catabolism in sensitive plants and that this is not a general phenomenon connected with inhibition of growth.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Herbicidas/farmacologia , Microssomos/enzimologia , Piridinas/farmacologia , Triticum/enzimologia , Diglicerídeos/metabolismo , Diquat/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Ácidos Graxos Insaturados/metabolismo , Cinética , Paraquat/farmacologia , Fosfatidilcolinas/metabolismo , Raízes de Plantas/enzimologia , Especificidade por Substrato , Triticum/crescimento & desenvolvimento
19.
Psychiatr Pol ; 32(2): 165-75, 1998.
Artigo em Polonês | MEDLINE | ID: mdl-9640985

RESUMO

A group of patients (52 women and 3 men) aged 12-39 with the diagnosis of anorexia nervosa (51 persons) and bulimia nervosa (4 persons) treated in the I Psychiatry Department of Medical University of Gdansk between 1972-1994 was studied. The diagnostic criteria were in accord with the DSM-IV. Among anorectic patients 45 persons were of restricting type and 6 were of bulimic type. Duration of illness was 1-14 years. Most of the patients were still students. Analysis of the aspects of eating disorders showed family conflict situations, single parents, conflicts between parents, competition at home. The patients presented fearful attitude, egocentrism, problems with acceptation of the gender role, obsessive-compulsive traits. In 36.7% cases minimal brain damage symptoms were found. Statistically significant weight gain was observed after neuroleptic treatment.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Adolescente , Adulto , Criança , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Feminino , Humanos , Masculino , Estudos Retrospectivos
20.
Science ; 280(5365): 915-8, 1998 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-9572738

RESUMO

Acetylenic bonds are present in more than 600 naturally occurring compounds. Plant enzymes that catalyze the formation of the Delta12 acetylenic bond in 9-octadecen-12-ynoic acid and the Delta12 epoxy group in 12,13-epoxy-9-octadecenoic acid were characterized, and two genes, similar in sequence, were cloned. When these complementary DNAs were expressed in Arabidopsis thaliana, the content of acetylenic or epoxidated fatty acids in the seeds increased from 0 to 25 or 15 percent, respectively. Both enzymes have characteristics similar to the membrane proteins containing non-heme iron that have histidine-rich motifs.


Assuntos
Asteraceae/metabolismo , Ácidos Graxos Dessaturases/química , Ácidos Oleicos/biossíntese , Oxirredutases , Proteínas de Plantas , Acetileno/metabolismo , Alcinos , Sequência de Aminoácidos , Arabidopsis/genética , Asteraceae/enzimologia , Asteraceae/genética , Catálise , Clonagem Molecular , DNA Complementar , Compostos de Epóxi/síntese química , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Genes de Plantas , Ferro/análise , Ácido Linoleico/metabolismo , Microssomos/metabolismo , Dados de Sequência Molecular , NAD/metabolismo , NADP/metabolismo , Ácidos Oleicos/síntese química , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/genética , Sementes/metabolismo , Alinhamento de Sequência
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