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1.
J Agric Food Chem ; 49(11): 5620-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11714369

RESUMO

Sterols in seeds, pulp/peel fractions, and whole berries of sea buckthorn (Hippophaë rhamnoides L.) samples belonging to two major subspecies (sinensis and rhamnoides) from Finland and China were analyzed as TMS derivatives by gas chromatography-mass spectrometry after saponification of the oils. The total sterol contents in the seeds, the fresh pulp/peel, and the whole berries were 1200-1800, 240-400, and 340-520 mg/kg, respectively. The corresponding values in the extracted oils were 12-23, 10-29, and 13-33 g/kg. Sitosterol constituted 57-76 and 61-83%, respectively, of the seed and pulp/peel sterols. The sterol content and composition showed little variation between subspecies and collection sites. Different harvesting dates showed significant effects on the levels of some sterols both in the seeds and in the pulp/peel. The sterol profiles obtained are useful for characterizing sea buckthorn and detecting adulterations of the valuable oils. The information provided by the present investigation is also important for further chemical investigation of sea buckthorn sterols and industrial utilization of the berries as a raw material of functional foods.


Assuntos
Rosales/química , Esteróis/química , Espectrometria de Massas , Rosales/embriologia , Sementes/química , Esteróis/isolamento & purificação
2.
Biochim Biophys Acta ; 1293(1): 97-105, 1996 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-8652634

RESUMO

1H-NMR spectroscopy was applied to a study of the mode of interaction, in aqueous medium in the pH range 5.2-8.5 and at low and high temperatures, between several mono- and dinucleotide analogues of the mRNA cap m7GpppG and a selected tripeptide Trp-Leu-Glu, and a tetrapeptide Trp-Glu-Asp-Glu, the sequence of which corresponds to one of the suspected binding sites in the mRNA cap-binding protein (CBP). A program, GEOSHIFT, was developed, based on ring-current anisotropy theory, for analysis of experimentally observed changes in chemical shifts accompanying interactions between aromatic heterocyclic rings. This permitted quantitative evaluation of stacking interactions between the m7G cap and the tryptophan indole ring, and the relative orientations of the planes of the two rings, spaced about 3.2 angstroms apart. The structures of the stacked complexes were determined. In particular, stacking between m(2,2,7)3G (which has no free amino group for hydrogen bonding) and the indole ring is weaker and quite different from that between m7G and m(2,7)2G and indole. With the dinucleotide cap-analogues, only the m7G component stacks with the indole ring, without disruption of intramolecular stacking. In contrast to numerous earlier reports, the calculated stacking interactions are quantitatively in accord with the values derived from fluorescence measurements. It also has been shown that the positively charged (cationic) form of m7G stacks much more efficiently with the indole ring than the zwitterionic form resulting from dissociation of the guanine ring N1H (pKa approximately 7.3).


Assuntos
Fosfatos de Dinucleosídeos/química , Oligopeptídeos/química , Análogos de Capuz de RNA/química , Triptofano/análise , Sequência de Aminoácidos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Indóis/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular , Oligopeptídeos/metabolismo , Análogos de Capuz de RNA/metabolismo , Proteínas de Ligação ao Cap de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Software , Temperatura
3.
J Infect Dis ; 171(4): 1060-4, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7706791

RESUMO

Peptidoglycan, a specific marker for all bacterial cell walls, was studied in peripheral blood of healthy human subjects by mass spectrometric analysis of muramic acid. Peripheral blood mononuclear and polymorphonuclear cells from 98 healthy adults were hydrolyzed and analyzed by gas chromatography-mass spectrometry as alditol acetate derivatives using selective ion monitoring. Muramic acid was observed in cell samples from 21 of 98 subjects. Blood cultures were done simultaneously and remained negative. As a control, mononuclear and polymorphonuclear cells separated from umbilical vein blood of 41 healthy newborns were studied; all were muramic acid-negative. Since newborns lack gut flora, intestinal absorption of bacteria or of their degradation products appears to be the most likely explanation for the finding.


Assuntos
Leucócitos/química , Ácidos Murâmicos/sangue , Adulto , Cromatografia Gasosa , Feminino , Humanos , Recém-Nascido , Masculino , Espectrometria de Massas , Peptidoglicano/sangue , Veias Umbilicais
4.
Br J Rheumatol ; 33(12): 1127-30, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8000740

RESUMO

Presence of muramic acid, a bacterial cell wall component, was analysed by gas chromatography-mass spectrometry in synovial fluid (SF) of 40 patients with acute inflammatory arthritis. SF muramic acid was observed in 4/14 patients with acute, culture negative inflammatory arthritis of unclear origin. Each of these four patients had a history of a recent bacterial disease (pansinuitis, purulent leg ulcer, erysipelas, unexplained fever with suspicion of cholecystitis and urinary tract infection). In the bacterial arthritis, SF muramic acid was detected in 6/12 patients (in 2/6 culture negative cases). In the reactive arthritis due to Salmonella or Yersinia, the rate of positivity was 2/14. Nineteen samples of traumatic SF effusion were muramic acid negative. These findings indicate that several cases of undefined acute inflammatory arthritis are of bacterial origin.


Assuntos
Artrite Reativa/metabolismo , Ácidos Murâmicos/análise , Infecções por Salmonella/metabolismo , Líquido Sinovial/química , Yersinia/metabolismo , Doença Aguda , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ácidos Murâmicos/metabolismo
5.
J Am Soc Mass Spectrom ; 5(2): 113-9, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24222522

RESUMO

Electron impact ionization mass spectrometry indicates that the behavior of W-unsubstituted pyrirnidin-4-ones with CH2-R type substitution at C-2 differs from homologs that are N-substituted and/or 2-aryl- or 2-methyl-substituted. A dominant intramolecular cycliza-tion was found to occur between 3ZV (in agreement with the predominance of the 3NH tautomers) and the ortho positions of the aryl moiety in compounds with a CH2-aryl substitution at C-2. Theoretical calculations with an AMI SCFR method on 2-, 6-, and 2, 6-disubstituted pyrimidin-4-ones support the mass spectrometric observations.

6.
J Chem Ecol ; 20(9): 2197-212, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24242801

RESUMO

Branched hydrocarbons were identified in the lipids ofLeptinotarsa decemlineata Say andTribolium destructor by gas chromatography, ordinary electron impact mass spectrometry, and linked, scanned, daughterion monitoring. This methodology allowed us to revise our earlier results based only on GC-MS data confirming the existence of only monomethyl-, dimethyl-, and trimethylalkanes in the hydrocarbons ofL. decemlineata Say. The hydrocarbons fromTribolium destructor consist ofn-alkanes, 3-methylalkanes, internally branched monomethylalkanes and dimethylalkanes. Daughter-ion monitoring can be particularly important for distinguishing between incidentally overlapped GC peaks of hydrocarbons from different series. A trace, for example, of dimethylalkane coeluating withn-alkane was easily identified in GC peak of hydrocarbon mixture ofT. destructor. Link scans confirmed also molecular weights for the compounds without molecular ions in the mass spectra. Structural assignment of the compounds were verified by comparison of the experimental and calculated values of the GC retention Kovats indexes (KI).

7.
Eur J Clin Microbiol Infect Dis ; 12(5): 330-5, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8354298

RESUMO

A combined gas chromatography-mass spectrometry (GC-MS) technique was used for serial determination of serum arabinitol levels in patients with postoperative candidiasis. Forty subjects were investigated, 18 patients with candidiasis, 7 patients with superficial Candida colonization and 15 postoperative control patients. The arabinitol levels were highly elevated, slightly elevated and normal in 13, 1 and 4 patients respectively with candidiasis; in 2, 2 and 3 colonized patients and in 1, 1 and 13 control patients (p < 0.001, chi 2, between all the groups). The sensitivity of a single arabinitol determination for detection of postoperative candidiasis was 27.6 % and the specificity 89.2 %. Use of multiple samples improved sensitivity up to 72.2% per patient (123 samples) with a specificity of 86.4 %. Highly elevated arabinitol concentrations were detected in only one patient before the onset of therapy. Determination of arabinitol levels by GC-MS is a specific test for diagnosing candidiasis, but multiple samples are required for adequate sensitivity, and the initiation of therapy must still be on an empirical basis.


Assuntos
Candidíase/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Complicações Pós-Operatórias , Álcoois Açúcares/sangue , Candidíase/diagnóstico , Distribuição de Qui-Quadrado , Creatinina/sangue , Humanos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
9.
Eur J Clin Microbiol Infect Dis ; 9(12): 873-9, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2127398

RESUMO

Gas-liquid chromatography-mass spectrometry was used to analyze the extracellular extracts of 108 coagulase-negative staphylococcal strains for the presence of mannose, galactose, glucose and ribose, in order to determine whether production of these four monosaccharides, regarded as potential staphylococcal slime components, was associated with the adherence capacity of the individuals strains. A total of 90 Staphylococcus epidermidis and 18 Staphylococcus hominis strains were studied. Using the quantitative spectrophotometric assay, 21 Staphylococcus epidermidis strains were classified as strongly adherent, 12 as moderately adherent, 11 as weakly adherent, and 46 as nonadherent. All 18 Staphylococcus hominis strains were nonadherent. Mannose, galactose, glucose and ribose were detected as the main monosaccharide components in the extracellular extracts of all strains examined. Moreover, the mean relative concentrations of these monosaccharides were essentially the same for the different adherence phenotypes within the species Staphylococcus epidermidis. These results showed that there was no causal connection between the adherence of coagulase-negative staphylococci and the extracellular production of any of the four monosaccharides analyzed.


Assuntos
Aderência Bacteriana , Monossacarídeos/biossíntese , Staphylococcus epidermidis/metabolismo , Staphylococcus/metabolismo , Galactose/biossíntese , Glucose/biossíntese , Manose/biossíntese , Ribose/biossíntese , Especificidade da Espécie , Staphylococcus/fisiologia , Staphylococcus epidermidis/fisiologia
10.
Eur J Clin Microbiol Infect Dis ; 9(4): 262-70, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2351142

RESUMO

To analyze immunochemically the extracellular slime substance of Staphylococcus epidermidis, rabbits were repeatedly immunized with the crude slime extract isolated from an adherent, slime-producing clinical Staphylococcus epidermidis strain. Immunoelectron microscopy demonstrated that the target antigens of the resulting antibodies were located in the extracellular slime-like layer of bacterial cells. When these target antigens were characterized by immunoblotting, a variety of antigens were detected, including many with molecular masses higher than 80 kilodaltons and also a predominant one with a molecular mass of 30 kilodaltons. No characteristic differences were observed between the tube adherence test positive and negative Staphylococcus epidermidis isolates. Although there was variation in the number and intensity of high molecular mass antigens, such variations did not correlate with the tube adherence test. Of the 110 Staphylococcus epidermidis isolates studied, 106 (96%) expressed the 30-kilodalton antigen. This component was found in no other Staphylococcus spp. examined in the study. The bacterial component was not only easily detached from bacterial cells but also water-soluble, characteristics implicating a slime-like nature. Further studies are needed to definitively establish the origin and nature of the 30-kilodalton Staphylococcus epidermidis-specific component, and determine its potential benefit as a diagnostic tool.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Glicoproteínas/análise , Lipoproteínas/análise , Staphylococcus epidermidis/análise , Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Cromatografia Gasosa , Eletroforese em Gel de Poliacrilamida , Glicoproteínas/imunologia , Humanos , Soros Imunes/imunologia , Immunoblotting , Imuno-Histoquímica , Lipoproteínas/imunologia , Microscopia Eletrônica , Staphylococcus epidermidis/imunologia , Staphylococcus epidermidis/ultraestrutura
11.
Anal Chem ; 61(7): 698-700, 1989 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2719267

RESUMO

Triacylglycerols (TAGs) from butter fat isolated by solvent extraction were analyzed by use of a capillary column supercritical fluid chromatograph (SFC) combined with a flame ionization detector or a double focusing mass spectrometer. The chromatographic separation was achieved by using a dimethyldiphenylpolysiloxane phase (DB-5) to bundle up the TAGs with the same carbon number. The ratio of TAGs with varying degree of unsaturation in each SFC peak was determined by using the selected ion monitoring of the molecular ions with electron impact mode. The discrimination between the fatty acids at the position sn-2 and positions sn-1/3 in a triacylglycerol molecule was demonstrated by monitoring the ions [M - RCO2CH2]+ from reference compounds.


Assuntos
Manteiga/análise , Triglicerídeos/análise , Cromatografia/métodos , Espectrometria de Massas/métodos
12.
Biochem J ; 232(1): 169-75, 1985 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-4084226

RESUMO

Human aortic elastin reduced with [3H]borohydride was analysed by ion-exchange chromatography after alkali or acid hydrolysis. Alkali hydrolysates of elastins contained a radioactive peak that was eluted between proline and leucine. This peak was not present in foetal elastin, but its proportion increased steadily during aging. Aortic samples from patients with annulo-aortic ectasia (aneurysm of the ascending aorta), including one with classical Marfan syndrome, contained less elastin (CNBr-insoluble material) than did the age-matched controls. The proportion of radioactivity in the new peak of all these aortas was low when compared with age-matched controls. Gas-chromatographic/mass-spectrometric analysis suggested that it contained a cyclic derivative of a hydrated aldol-condensation product. The concentration of the cross-link precursors, lysine aldehyde and aldol-condensation product (estimated from the acid-hydrolysis product 6-chloronorleucine and the acid-degradation product of reduced aldol-condensation product) was high in very young aortas but remained quite stable after childhood. No differences were observed in cross-link profiles of acid hydrolysates between pathological and control aortas. A low proportion of radioactivity in the new peak may indicate the presence of young or immature elastin in the pathological aortas.


Assuntos
Aminoácidos/análise , Aorta/análise , Elastina , Adulto , Fatores Etários , Doenças da Aorta/metabolismo , Boroidretos , Criança , Cromatografia por Troca Iônica , Dilatação Patológica/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrólise , Masculino , Síndrome de Marfan/metabolismo , Pessoa de Meia-Idade
13.
Rev. Col. Bras. Cir ; 8(3): 119-22, 1981.
Artigo em Português | LILACS | ID: lil-11466

RESUMO

A esofagectomia subtotal pode ser indicada nas afeccoes malignas ou benignas do esofago com intenso comprometimento do orgao, principalmente megaesofago e esofagite de refluxo. Devido a situacao topografica do orgao que e situado em 3 regioes, cervical toracica e abdominal e pela sua conexao com estruturas nobres, a sua resseccao exige uma serie de manobras tecnicas com cias que se associam as repercussoes locais e gerais determinadas pela propria afeccao que motivou a sua retirada.No cancer do esofago, com efeito, as alteracoes nutricionais sao acentuadas, e a sua participacao interfere bastante nas consequencias do tratamento cirurgico.O objetivo deste estudo e analisar as complicacoes imediatas que se seguem a esofagectomia subtotal no tratamento do cancer do esofago


Assuntos
Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Neoplasias Esofágicas , Procedimentos Cirúrgicos Operatórios , Complicações Pós-Operatórias
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