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1.
Sci Total Environ ; 353(1-3): 287-99, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16274732

RESUMO

Bacteria and diatom strains from the Adriatic Sea were investigated, under standard and altered environmental conditions, for carbohydrate production and for the presence of specific biomarkers. Algae from P-depleted cultures showed an increase in extracellular carbohydrate production, a significantly lower chlorophyll a content and unchanged total lipid levels. However, the fatty acid composition of algal cultures was severely affected by low P levels, in that, total saturated and monounsaturated fatty acids increased and total polyunsaturated fatty acids decreased. Marine heterotrophic bacteria resulted enriched by 4 to 6 orders of magnitude in mucilage samples respect to surrounding seawater, unlike other groups of bacteria such as the non-halophylic heterotrophs. The major fatty acids detected in bacteria were 16:0 and 18:1n-7; the uneven fatty acids 17:0i, 17:0 and 17:1 also constituted an important component of various strains and, as a result, the total monounsaturated fraction represented the main component of total fatty acids. All the mucilage samples analysed shared the same general fatty acid composition features with a high amount of saturated components, especially 16:0; typical marine polyunsaturated fatty acids, such as 20:5n-3 and 22:6n-3, were found at very low levels. With regard to the sterol composition, the analysed algal species and bacteria showed that different compounds prevailed in the different species, and under P-deprivation sterol distribution resulted differently affected in the various algal species. In mucilage samples an overall prevalence of cholesterol was observed and, among 4alpha-methylsterols, constantly present, dinosterol prevailed in all samples. Vibrational IR spectroscopic analyses confirmed the main results obtained with the GC analysis: a higher unsaturation degree in nutrient replete diatom cultures than in P-depleted ones, a lower amount of P-containing compounds in the latter, bacterial lipid profiles with a high amount of free carboxylic acids and/or ketones and a low unsaturation degree and, finally, mucilage samples with a very low unsaturation degree. All these results allowed some speculations on the involvement of the various microbial and phytoplankton components in mucilage genesis.


Assuntos
Bactérias/química , Diatomáceas/química , Biologia Marinha/estatística & dados numéricos , Fitoplâncton/química , Biomarcadores/metabolismo , Carboidratos/análise , Células Cultivadas , Clorofila/análise , Clorofila A , Cromatografia Gasosa , Lipídeos/análise , Mar Mediterrâneo , Água do Mar/química , Especificidade da Espécie , Espectrofotometria Infravermelho , Esteróis/análise
2.
Biopolymers ; 72(2): 86-95, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12583011

RESUMO

Lipids from human renal tissues are studied by means of (1)H- and (13)C-NMR spectroscopy. The total lipid fractions obtained from healthy kidneys, malignant renal cell carcinomas, and benign oncocytomas are characterized and analyzed to elucidate the main differences between the functional and neoplastic tissues. In all cases the lipid components are well identified. The healthy kidney is characterized by high amounts of triglycerides and the presence of cholesterol in its free form. On the contrary, renal cell carcinomas contain high amounts of cholesterol that are almost completely esterified as oleate, suggesting an intracellular localization of the cholesteryl esters synthesis. Cholesteryl esters are considered markers of renal cell carcinomas, thus supporting recent theories that these compounds play a leading role in cell proliferation. Oncocytomas are particularly rich in phosphatidylcholine and, analogous to the healthy kidney, are completely lacking in cholesteryl esters. Healthy kidneys and oncocytomas appear to have other similarities if compared with renal cell carcinomas: a very high fatty acyl/cholesterol ratio, the presence of dolichols, and a higher grade of unsaturation. The (13)C data suggest a new method for the direct evaluation of the saturated/unsaturated fatty acyl ratio.


Assuntos
Rim/química , Lipídeos/análise , Espectroscopia de Ressonância Magnética/métodos , Carcinoma de Células Renais/química , Humanos , Lipídeos/química
3.
Int J Mol Med ; 11(1): 95-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12469226

RESUMO

Cholesteryl esters (CholE) were detected in human malignant neoplasms by means of in vitro nuclear magnetic resonance spectroscopy. Spectroscopic analysis of the total lipid extracts obtained from cerebral tumors revealed appreciable amount of esterified cholesterol in high grade gliomas such as glioblastomas and anaplastic oligodendrogliomas, characterized by prominent neovascularity. The finding that no CholE were detected in the healthy brain and in low grade and benign tumors supports a possible correlation between this class of lipids and histological vascular proliferation. Compared with high grade gliomas, renal cell carcinomas show higher levels of CholE, absent in the healthy renal parenchyma and in benign oncocytomas. In nefro-carcinomas, cytoplasmic lipid inclusions and prominent vascularization contribute to the increased levels of CholE present mainly as oleate. CholE are discussed as potential biochemical markers of cancer and as a target for new therapeutic strategies.


Assuntos
Neoplasias Encefálicas/patologia , Ésteres do Colesterol/análise , Biópsia , Neoplasias Encefálicas/cirurgia , Glioma/patologia , Glioma/cirurgia , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Espectroscopia de Ressonância Magnética , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Oligodendroglioma/patologia , Oligodendroglioma/cirurgia
4.
Biopolymers ; 67(6): 428-39, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12209451

RESUMO

Fourier transform Raman (FT Raman) and IR (FTIR) and (1)H-NMR spectroscopies coupled with differential scanning calorimetry (DSC) were applied to the characterization of root exudates from two cultivars of gladiolus (Spic Span and White Prosperity) with different degrees of resistance and susceptibility to Fusarium oxysporum gladioli, the main pathogen of gladiolus. This work was aimed at correlating the composition of root exudates with the varietal resistance to the pathogen. Spectroscopic analysis showed that White Prosperity root exudate differs from Spic Span root exudate by a higher relative amount of the aromatic-phenolic and sugarlike components and a lower relative amount of carbonylic and aliphatic compounds. DSC analysis confirmed the spectroscopic results and showed that White Prosperity root exudate is characterized by an aromatic component that is present in a higher amount than in the Spic Span root exudate. The results are discussed in relation to the spore germination tests showing that White Prosperity, which is characterized by a remarkable resistance toward F. oxysporum gladioli, exudes substances having a negative influence on microconidial germination of the pathogen; root exudates from Spic Span, one of the most susceptible cultivars to F. oxysporum gladioli, proved to have no effect. White Prosperity's ability to inhibit conidial germination of F. oxysporum gladioli can be mainly related to the presence of a higher relative amount of aromatic-phenolic compounds.


Assuntos
Farmacorresistência Fúngica , Fusarium/efeitos dos fármacos , Liliaceae , Extratos Vegetais/farmacologia , Fusarium/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Raízes de Plantas/química , Especificidade da Espécie , Espectrofotometria Infravermelho , Vibração
5.
Oncol Rep ; 8(6): 1337-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11605061

RESUMO

This study shows how 1H magnetic resonance spectroscopy (1H MRS) can help to elucidate a clinical case when MR images suggest a diagnosis of central nervous system (CNS) neoplasm. The in vivo MRS metabolic profile in our cases did not correspond to literature reports of brain tumors, but reflected the histopathological response of hematoma and the in vitro 1H MR spectra of the biopsy obtained at surgery. The in vitro spectrum of the aqueous extracts of the examined lesion were compared with those of two common CNS tumors. The lipid fraction spectrum of the lesion agreed with both the spectrum of the aqueous extracts and the histological diagnosis.


Assuntos
Neoplasias Encefálicas/diagnóstico , Doenças do Sistema Nervoso Central/diagnóstico , Hematoma/diagnóstico , Espectroscopia de Ressonância Magnética , Biópsia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/patologia , Diagnóstico Diferencial , Feminino , Hematoma/metabolismo , Hematoma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
6.
Artigo em Inglês | MEDLINE | ID: mdl-11413828

RESUMO

A study to monitor the composting process, to evaluate the effectiveness of bioindicators for the quality and maturity of cured compost obtained by a mixture of winery residues, sludges from dairies and solid residues from food processing (grape-stalks, grape-dregs, rice husks), was conducted. Composting process lasting five months was monitored by chemico-physical, spectroscopic (FTIR, DTG and DSC), microbiological and enzymatic analyses. Biological activities (ATP, DHA contents and several enzymatic activities), impedance variations (DT) of mixed cultures during growth and potential pathogens (E. coli and Salmonella sp.), were determined. The phytotoxicity tests gave a germination index higher than 90% and no significant genotoxic differences between controls and the compost samples were evidenced. Pathogens were not found on the cured compost that can therefore be satisfactorily used as amendment for agricultural crops. However, no single measurement of a composting process factor, biological, chemical or physical, gave a comprehensive view of the quality of a specific composting. We proposed a tool of bioindicators of potential activity and markers in combination for integrated evaluation of monitoring of composting process and compost quality. The responses of several enzymatic activities were positive and indicative of their favorable use capable to reveal even very small changes within microbial population and activity in test and monitoring of compost programmes.


Assuntos
Agricultura , Indústria Alimentícia , Eliminação de Resíduos/métodos , Animais , Bactérias , Biodegradação Ambiental , Biomarcadores/análise , Conservação dos Recursos Naturais , Escherichia coli/isolamento & purificação , Dinâmica Populacional , Salmonella/isolamento & purificação , Microbiologia do Solo
7.
Biopolymers ; 62(6): 297-306, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11857268

RESUMO

Multinuclear ((1)H, (13)C, and (31)P) magnetic resonance spectroscopy are applied to the biochemical characterization of the total lipid fraction of healthy and neoplastic human brain tissues. Lipid extracts from normal brains, glioblastomas, anaplastic oligodendrogliomas, oligodendrogliomas, and meningiomas are examined. Moreover, the unknown liquid content of a cyst adjacent to a meningioma is analyzed. Two biopsies from glioblastomas are directly studied by (1)H-NMR without any treatment (ex vivo NMR). The (1)H- and (13)C-NMR analysis allows full characterization of the lipid component of the cerebral tissues. In particular, the presence of cholesteryl esters and triglycerides in the extracts of high grade tumors is correlated to the vascular proliferation degree, which is different from normal brain tissue and low grade neoplasms. The (31)P spectra show that phosphatidylcholine is the prominent phospholipid and its relative amount, which is higher in gliomas, is correlated to the low grade of differentiation of tumor cells and an altered membrane turnover. The ex vivo (1)H-NMR data on the glioblastoma samples show the presence of mobile lipids that are correlated to cell necrotic phenomena. Our data allow a direct correlation between biochemical results obtained by NMR and the histopathological factors (vascular and cell proliferations, differentiation, and necrosis) that are prominent in determining brain tumor grading.


Assuntos
Química Encefálica , Neoplasias Encefálicas/química , Lipídeos/química , Neoplasias Encefálicas/patologia , Isótopos de Carbono , Colesterol/análise , Ésteres do Colesterol/análise , Glioblastoma/química , Humanos , Hidrogênio , Lipídeos/análise , Neoplasias Meníngeas/química , Meningioma/química , Ressonância Magnética Nuclear Biomolecular , Oligodendroglioma/química , Fósforo , Triglicerídeos/análise
8.
Oncol Rep ; 7(6): 1355-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11032943

RESUMO

Samples from ten patients with renal cell carcinomas (RCC) were examined by 1H MRS and high performance liquid chromatography (HPLC) measurements. Twenty samples, ten from the tumor and ten from the surrounding healthy renal region were obtained. MRS yielded information on renal osmolytes which can be considered markers of physiological kidney function. The marked decrease of these osmolytes is a hallmark of cancer. Moreover, HPLC measurements disclosed the amino acid pattern of both healthy and neoplastic tissues. The Glu and Ea content had statistical significance. GSH was present in tumor tissues only.


Assuntos
Carcinoma de Células Renais/induzido quimicamente , Neoplasias Renais/induzido quimicamente , Aminoácidos/análise , Biomarcadores Tumorais/análise , Cromatografia Líquida de Alta Pressão , Ácido Glutâmico/análise , Humanos , Rim/química , Ressonância Magnética Nuclear Biomolecular , Taurina/análise
9.
Biopolymers ; 57(3): 140-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10805911

RESUMO

In this work calcium phosphate (CaP) compounds with different PO(3-)(4)/HPO(2-)(4) R molar ratios in the 0.65-149 range were synthesized. In fact, all these CaPs contain different amounts of HPO(2-)(4) and PO(3-)(4) ions as well as the amorphous precursors (tricalcium phosphate and octacalcium phosphate) of hydroxyapatite deposition, which was shown by in vitro and in vivo measurements. Spectroscopical IR and Raman results showed the presence of bands whose intensity ratio can be related to the molar ratio R; in particular, the Raman I(962)/I(987) and the IR I(1035)/I(1125) intensity ratios were characterized as markers of the molar ratio. For these CaP compounds a nucleation model, which was based on the ability of HPO(2-)(4) ions to form strong H bonds with PO(3-)(4) ions, was proposed.


Assuntos
Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Hidroxiapatitas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Relação Estrutura-Atividade , Vibração
10.
Minerva Stomatol ; 44(1-2): 33-42, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-7783710

RESUMO

In this study the following biomaterials were analysed by means of Fourier transform infrared vibrational spectroscopy (FTIR); they are: reabsorbable Dac Blu, non reabsorbable Dac Blu, non reabsorbable atomized Dac Blu, non reabsorbable fine Dac Blu, reabsorbable Biocoral 450, Calcitite 2040-12, Orthogel, Apagen, BTF 65, Calcitite 4060-2 Osprogel, Bio-Oss, Biostite, Osprovit, Merck Hydroxyapatite. The analysis was performed with a Jasco 5300-FTIR. At 64 readings for spectrum with a 2 cm-1 resolution. By means of this method it has been possible to perform a structural study at a molecular level of the commercial products mentioned before. The analysis showed which of the samples examined had lost the apatite OH- group during production. It also allowed the identification of some of the hydroxyapatites examined as carbonate apatites. Finally, it allowed the identification and quantification of the organic substances in the examined products.


Assuntos
Materiais Biocompatíveis/análise , Materiais Dentários/análise , Minerais/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação
11.
Minerva Stomatol ; 44(1-2): 69-74, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-7783713

RESUMO

In this work we relate about the results coming from crystallographic, physical and mineral tests taken on following biomaterials used in odontostomatology: reabsorbable Dac Blu, non reabsorbable Dac Blu, not reabsorbable atomized Dac Blu, not reabsorbable thin Dac Blu, reabsorbable Biocoral 450, Calcitite 2040-12, Orthogel, Apagen, BTF 65, Calcitite 4060-2, Osprogel, Bio-Oss, Biostite, Osprovit, Merck Hydroxiapatite. The data were obtained using the following tests: XRF, XRD, FTIR, TG, DTG, DTA, SEM. The results, although taken on few samples, showed that these biomaterials present a variability in some features, which can define the structural functionality.


Assuntos
Materiais Biocompatíveis/análise , Materiais Dentários/análise , Minerais/análise , Materiais Biocompatíveis/química , Materiais Dentários/química , Teste de Materiais , Minerais/química
12.
Epidemiol Prev ; 12(44): 25-30, 1990 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-2151133

RESUMO

A cluster of 7 lung cancer deaths among workers of a small tannery in Biella is reported. The major process in the plant, until the end of World War II, was chromium and vegetable tanning. A historical cohort study was carried out on a total of 353 male workers. The expected number of death was estimated on the basis of local mortality rates. An SMR for lung cancer of 449 (95% C.L. 180-925) was found for the entire cohort. Excluding workers non specifically employed in tanning operations, the SMR for lung cancer increased to 1087 (95% C.L. 352-2533). In order to control for potential confounders a nested case-control study was planned. The next-of-kin of 8 cases deceased for lung cancer and 32 controls matched by age were interviewed on smoking habits and previous jobs. Logistic regression analysis showed an O.R. of 6.94 (95% C.L. 1.18-40.73), adjusted for smoking habits and occupational history, for subjects involved in tanning operations. A registry of incident cases of cancer was established in order to avoid biased findings based on cluster cases.


Assuntos
Surtos de Doenças , Neoplasias Pulmonares/epidemiologia , Doenças Profissionais/epidemiologia , Curtume , Adulto , Estudos de Casos e Controles , Análise por Conglomerados , Humanos , Itália/epidemiologia , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Ocupações , Análise de Regressão , Fatores de Risco , Fumar
13.
Arch Sci Med (Torino) ; 134(3): 293-300, 1977.
Artigo em Italiano | MEDLINE | ID: mdl-603389

RESUMO

Thin layer chromatography was used to separate the triglyceridic fraction of plasma lipides in normal (19) and thalassaemic (15) subjects. Gas chromatographic analysis of the fraction was then carried out and the fatty acids represented were identified qualitatively and quantitatively. Statistically significant variations, specifically increase in arachidonic acid and reduction in palmitic and linoleic acids, were observed in the thalassaemic patients.


Assuntos
Ácidos Graxos/análise , Talassemia/sangue , Triglicerídeos/sangue , Cromatografia Gasosa , Cromatografia em Camada Fina , Humanos , Triglicerídeos/análise
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