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1.
J Clin Invest ; 89(3): 816-23, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1541674

RESUMO

We have compared gas chromatography and mass spectrometry (GC-MS) analysis with the Limulus amebocyte lysate (LAL) assay to quantify native meningococcal lipopolysaccharides (LPS) in five patient plasmas containing greater than 5 micrograms/liter by LAL. 3-Hydroxy lauric acid (3-OH-12:0) was used as a specific lipid A marker of neisserial LPS. The quantitative LAL results were confirmed by GC-MS (r = 0.98, P = 0.006). Seven patient plasmas were centrifuged at 103,000 g and the sedimentation behavior of native LPS compared with reference plasma proteins and with apo A1 and apo B100 representing high and low density lipoproteins. After 15 min of centrifugation, 84 +/- 2% (mean +/- SE) of the recovered LPS were found in the lower one-third of the centrifuged volume, whereas 6 +/- 1% remained in the upper one-third volume, indicating that meningococcal endotoxin circulates as complexes with high sedimentation coefficients. Bacterial outer membrane fragments were detected in the bottom fractions of three patient plasmas examined by means of electron microscopy. In three patient plasmas ultracentrifuged for 60 min at 103,000 g, the levels of apo A1 and apo B100 revealed minor changes, whereas only 1 +/- 1% of the recovered LPS remained in the upper one-third and 91 +/- 2% were found in the lower one-third volume. Few bioreactive LPS appear to be complexed with high and low density lipoproteins in meningococcal septic shock plasma.


Assuntos
Endotoxinas/sangue , Lipopolissacarídeos/sangue , Neisseria meningitidis/metabolismo , Choque Séptico/sangue , Escherichia coli/patogenicidade , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Teste do Limulus , Microscopia Eletrônica , Ultracentrifugação
2.
APMIS ; 96(6): 497-502, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3395476

RESUMO

The DNA-DNA homologies obtained were more than 90 per cent for all strains examined, including the reference strains of Mycobacterium paratuberculosis and Mycobacterium avium. Consequently, in a genetic sense, M. paratuberculosis with its variants belong to a single species which should be considered a subspecies of M. avium. The same reference strains of M. paratuberculosis and M. avium showed small but distinct differences in the cellular fatty acid patterns. The Norwegian goat isolate proved to be M. paratuberculosis, while the three sheep isolates from Iceland and the Faroe Islands showed a typical M. avium pattern.


Assuntos
DNA Bacteriano/análise , Ácidos Graxos/análise , Mycobacterium/classificação , Paratuberculose/microbiologia , Animais , Bovinos , Galinhas , Cabras , Mycobacterium/genética , Mycobacterium avium/classificação , Mycobacterium avium/genética , Hibridização de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico , Ovinos
3.
APMIS ; 97(11): 1037-45, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2590535

RESUMO

Capillary gas chromatography of cellular fatty acids and alcohols has been used as a routine method for a period of two years in the mycobacterial diagnostic laboratory of Statens institutt for folkehelse, Oslo, Norway. All mycobacteria (165 isolates) other than Mycobacterium tuberculosis (MOTT) and 24 randomly selected M. tuberculosis isolates were studied. Twelve characteristic lipid constituents allowed the construction of a diagnostic scheme. Without exceptions, all 36 examined isolates belonging to the M. tuberculosis-complex were characterized by a relatively high concentration level of hexacosanoic acid (mean: 4%, range: 1-13%), low level of tetracosanoic acid (mean: 1%, range: 0.1-3%), lack of methylbranched acids other than tuberculostearic acid, and lack of fatty alcohols. Members of the MAIS-complex (73 isolates) were all characterized by the general presence of the fatty alcohols 2-octadecanol (mean: 2%, range: 0.1-5%) and 2-eicosanol (mean: 7%, range: 2-21%), relatively high levels of tetracosanoic acid (mean: 5%, range: 1-15%) and lack (or trace) of hexacosanoic acid and methylbranched acids other than tuberculostearic acid. All 16 isolates of M. gordonae were easily recognized by their unique lack of tuberculostearic acid and their content of 2-methyl-tetradecanoic acid (mean: 5%, range: 2-12%), and the M. xenopi isolates were the only examined strains containing the fatty alcohol 2-docosanol (mean: 9%, range: 2-13%). The six M. malmoense strains contained the two unique constituents 2-methyl eicosanoic acid (mean: 3%, range: 1-4%) and 2,4,6-trimethyl tetracosanoic acid (mean: 3%, range: 2-4%). The ten strains of M. kansasii were characterized by 2,4-dimethyl tetradecanoic acid (mean: 5%, range: 1-11%), whereas the seven strains of M. marinum shared 2,4-dimethyl hexadecanoic acid (mean: 4%, range 0.2-12%) as a specific marker.


Assuntos
Álcoois/análise , Ácidos Graxos/análise , Mycobacterium/análise , Cromatografia Gasosa , Infecções por Mycobacterium/diagnóstico , Ácidos Micólicos/metabolismo
4.
APMIS ; 100(1): 91-4, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1311182

RESUMO

Monoclonal antibodies (MAbs) were produced against pneumococcal capsular polysaccharides after subcutaneous immunization of BALB/c mice with a 23-valent vaccine (Pneumovax N, Merck, Sharp & Dohme). Selected antibodies were tested in ELISA against individual polysaccharides from 23 different pneumococcal types and in a dot blot assay with heat-killed whole bacteria adhered to nitrocellulose paper. Three MAbs (isotype IgM) were found to be specific for types 4, 8 and 22F, respectively, whereas one (isotype IgA) reacted both with 19A and 19F. Very mild acid hydrolysis of the capsular polysaccharides resulted in loss of reaction with the antibodies.


Assuntos
Anticorpos Monoclonais/imunologia , Polissacarídeos Bacterianos/imunologia , Streptococcus pneumoniae/imunologia , Animais , Vacinas Bacterianas/imunologia , Camundongos , Ácido Periódico/química , Polissacarídeos Bacterianos/química
5.
APMIS ; 107(2): 231-9, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10225322

RESUMO

Twenty-one mycobacterial type strains and 334 clinical isolates of mycobacteria were identified by standardized sequence analysis using part of the gene encoding 16S rRNA. Apart from two clinical isolates, the resulting sequences corresponded to previously published sequences. The results of the molecular determinations of the type strains completely overlapped the identities obtained using conventional techniques (cultural characteristics, biochemical tests, commercial DNA probes, and gas chromatographic lipid profiles). Of 323 isolates conventionally identified as slow-growing mycobacteria, 318 (98.5%) were identified to the same species or group level by 16S rDNA sequence analysis, while 6 of the 11 strains of rapid growers obtained a corresponding identity with the two approaches. The sequencing protocol combined with a few cultural characteristics (i.e. growth rate, pigmentation and susceptibility testing) offers a rapid, reliable and usually definite identification of mycobacterial isolates.


Assuntos
DNA Bacteriano/análise , DNA Ribossômico/análise , Mycobacterium/genética , RNA Ribossômico 16S/análise , Sequência de Aminoácidos , Sequência de Bases , Humanos , Dados de Sequência Molecular , Mycobacterium/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
6.
FEMS Microbiol Lett ; 106(3): 315-20, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8454196

RESUMO

Four long-chain fatty acids, 2-hydroxy-27-oxo-octacosanoic acid (n28:0(2-OH,27-oxo)), 2-hydroxy-29-oxo-triacontanoic acid (n30:0(2-OH,29-oxo)), 2-hydroxy-heptacosane-1,27-dioic acid (27:0(2-OH)-dioic) and 2-hydroxy-nonacosane-1,29-dioic acid (29:0(2-OH)-dioic) were identified by GLC-MS analysis in the phenol-chloroform-petroleum ether (PCP) extracts of Legionella jordanis, L. maceachernii and L. micdadei indicating that they are constituents of lipopolysaccharide. Moreover, five long-chain fatty acids (28:0(27-OH), 28:0(27-oxo), 30:0(29-oxo), 27:0-dioic and 29:0-dioic) previously identified in L. pneumophila (Moll, H. et al., FEMS Microbiol. Lett., 97 (1992), 1-6) were also found in these species. This is to our knowledge the first report on the existence of long chain 2-hydroxylated (omega-1)-oxo fatty acids and 2-hydroxylated 1,omega-dioic fatty acids.


Assuntos
Ácidos Graxos/isolamento & purificação , Legionella/química , Parede Celular/química , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Peso Molecular , Especificidade da Espécie
7.
FEMS Microbiol Lett ; 76(1-2): 1-6, 1992 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1426993

RESUMO

Two long-chain fatty acids, 27-oxo-octacosanoic acid (28:0(27-oxo)) and heptacosane-1,27-dioic acid (27:0-dioic) were identified for the first time in phenol-chloroform-petroleum ether extracts of Legionella pneumophila, indicating that they are constituents of lipopolysaccharide. The fatty acids were characterised by combined gas-liquid chromatography/mass spectrometry and proton nuclear magnetic resonance spectroscopy. Moreover, minor amounts of 29-oxo-triacontanoic (30:0(29-oxo)) acid and nonacosane-1,29-dioic acid (29:0-dioic) as well as 27-hydroxy-octacosanoic acid (28:0(27-OH)) were present in the phenol-chloroform-petroleum ether extract.


Assuntos
Ácidos Dicarboxílicos/isolamento & purificação , Cetoácidos/isolamento & purificação , Legionella pneumophila/química , Ácidos Graxos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Lipopolissacarídeos/química , Espectroscopia de Ressonância Magnética
8.
Carbohydr Res ; 245(1): 129-36, 1993 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-8358744

RESUMO

A capsular polysaccharide, isolated from the mucoid Moraxella nonliquefaciens strain 3828/60, has been investigated by component analyses, periodate oxidation, methylation analyses, mass spectrometry, 1H and 13C NMR spectroscopy, and hydrolysis to give a disaccharide that was isolated and characterised. The results showed that the polysaccharide has the repeating unit-->3)-beta-D- GalpNAc-(1-->5)-beta-Kdo p-(2-->, with approximately 40% of O-8 of Kdo being acetylated.


Assuntos
Dissacarídeos/química , Moraxella/metabolismo , Polissacarídeos Bacterianos/química , Configuração de Carboidratos , Sequência de Carboidratos , Dissacarídeos/isolamento & purificação , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metilação , Dados de Sequência Molecular , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/isolamento & purificação
9.
Clin Neurol Neurosurg ; 86(1): 29-32, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6325067

RESUMO

Twenty-six non-randomized patients with carpal tunnel syndrome are presented. It is documented that three out of four patients may be diagnosed pre-operatively by five or more clinical parameters. All patients were screened for amyloidosis in biopsies from the carpal tunnel. One patient presented amyloid deposits in the transversal carpal ligament. The importance of macro- and microscopic findings in the carpal tunnel inclusive local amyloidosis for the pathogenesis of the carpal tunnel is discussed. It is concluded that provided systemic amyloidosis is not suspected, screening for amyloidosis may have diagnostic interest, however without therapeutic consequences and therefore unnecessary.


Assuntos
Amiloidose/diagnóstico , Síndrome do Túnel Carpal/diagnóstico , Adulto , Idoso , Amiloidose/complicações , Amiloidose/patologia , Biópsia , Síndrome do Túnel Carpal/complicações , Síndrome do Túnel Carpal/patologia , Eletromiografia , Feminino , Humanos , Ligamentos/patologia , Masculino , Pessoa de Meia-Idade
13.
J Gen Microbiol ; 123(1): 163-71, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7320695

RESUMO

Fatty acids of Fusobacterium species were examined by gas-liquid chromatography. Fusobacterium nucleatum, F. necrophorum, F. mortiferum, F. gonidiaformans and F. varium showed similar patterns, characterized by the presence of 3-hydroxytetradecanoate, n-tetradecanoate, hexadecenoate, n-hexadeconoate, ocadecenoate, n-octadecanoate and a component having the properties of octadecadienoate. Fusobacterium nucleatum contained 3-hydroxyhexadecanoate as a distinctive character. Simpler fatty acid patterns characterized by the absence of 3-hydroxytetradecanoate and other hydroxy fatty acids were observed in F. plauti, the single strain of F. prausnitzii and in the majority of strains classified as F. russii and F. naviforme. Neither methyl-branched nor cyclopropane fatty acids could be detected in any of the strains examined. In addition to fatty acid methyl esters, the chromatographic profiles of all species except F. mortiferum, F. gonidiaformans and F. naviforme contained substantial amounts of fatty aldehyde dimethyl acetals of chain lengths C14 to C18.


Assuntos
Ácidos Graxos/análise , Fusobacterium/análise , Cromatografia Gasosa , Fusobacterium/classificação , Fusobacterium necrophorum/análise , Fusobacterium necrophorum/classificação
14.
J Chromatogr ; 370(1): 103-12, 1986 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-3805213

RESUMO

Several conditions of acidic anhydrous methanolysis were examined to optimize the release and minimize the degradation of unphosphorylated 2-keto-3-deoxy-D-manno-octonic acid (KDO) from bacterial lipopolysaccharides and polysaccharides. The reaction was monitored by capillary gas chromatography after derivatization by trifluoroacetic anhydride. The best results were obtained by use of 2 M hydrochloric acid at 60 degrees C for 2 h. Under these conditions a single KDO component appeared, and KDO was quantitatively released from all model compounds except when glycosidically linked to hexosamines. For quantitative cleavage of this linkage a reaction time of 6 h was required at 60 degrees C, giving rise to 5-10% of secondary KDO products. The KDO detection limit was about 250 pmol (50 ng) and the molar response was the same as for glucose. The KDO derivative gave a mass spectrometric fragmentation pattern consistent with a pyranosidic methylketoside methyl ester structure. Differentiation of KDO linkage types could be obtained by determination of the rates of KDO release by mild methanolysis.


Assuntos
Lipopolissacarídeos/análise , Açúcares Ácidos/análise , Fenômenos Químicos , Físico-Química , Cromatografia Gasosa , Estabilidade de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Metanol , Ácido Trifluoracético
15.
J Gen Microbiol ; 131(1): 175-9, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3989506

RESUMO

Fatty acids of 16 strains of Selenomonas isolated from the human oral cavity were examined by gas-liquid chromatography. The strains showed similar patterns, characterized by the presence of straight-chain fatty acids in the range C11 to C18. Fatty acids of odd-numbered carbon atoms dominated and the major acids were n-pentadecanoate and 3-hydroxytridecanoate. The general fatty acid pattern of Selenomonas differed distinctly from those of other previously analysed anaerobic or microaerophilic Gram-negative bacilli.


Assuntos
Bacteroidaceae/análise , Ácidos Graxos/análise , Bacteroidaceae/classificação , Bacteroidaceae/isolamento & purificação , Criança , Cromatografia Gasosa , Placa Dentária/microbiologia , Humanos
16.
Acta Pathol Microbiol Scand B ; 84(4): 177-88, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-961430

RESUMO

Sixty-four strains of Neisseria, Moraxella, and Acinetobacter were screened for cellular monosaccharides by gas-liquid chromatography and other chromatographic techniques. The four sugars ribose, glucose, glucosamine, and 2-keto-3-deoxyoctonate (KDO) were detected in all strains. Heptose was detected only in "true neisseriae" (Neisseria gonorrhoeae, N. meningitidis, N. sicca, N. cinerea, N. flavescens, and N. elongata) and in the tentaively named species Moraxella urethralis. Some marked interspecies dissimilarities within groups were revealed. Thus, N. ovis and M. atlantae were characterized by the presence of mannose. Intraspecies differences were also encountered. N. meningitidis strains of serogroups B and C were distinguished from strains of serogroup A by their sialic acid content. This sugar was also detected in two out of three examined strains of M. nonliquefaciens. In Acinetobacter, heterogeneity of monosaccharide patterns was rather pronounced. The results show the applicability of gas chromatographic "monosaccharide" profiles fo whole cells or extracted carbohydrate in bacterial classification and identification, including differentiation at the subspecies level. In addition, such profiles may be useful for monitoring during purification of cellular polysaccharides.


Assuntos
Acinetobacter/análise , Monossacarídeos/análise , Moraxella/análise , Neisseria/análise , Cromatografia Gasosa , Cromatografia em Papel , Cromatografia em Camada Fina , Galactose/análise , Glucosamina/análise , Glucose/análise , Heptoses/análise , Cetoses/análise , Manose/análise , Ramnose/análise , Ribose/análise , Ácidos Siálicos/análise , Açúcares Ácidos/análise
17.
Fresenius J Anal Chem ; 366(5): 470-5, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11220341

RESUMO

Although organolead as a gasoline additive is banned in most countries, contamination by organolead compounds is still present. Little is known about transformation reactions of organolead compounds and especially transalkylation reactions with other metals. Laboratory experiments to clarify transalkylation reactions between organolead and inorganic mercury, and investigations of sites, where organolead compounds were emitted, are reported. Under laboratory conditions, inorganic mercury is ethylated to ethylmercury+ in presence of tetraethyllead. These transalkylations take place very fast and almost completely. In soil samples from an industrial site contaminated with organolead compounds and inorganic mercury, EtHg+ was clearly identified in high concentrations (up to 46 mg Hg/kg dw). Furthermore, methylmercury+ was found in concentrations up to 27 mg Hg/kg dw. It is the first time, that a transethylation of an organolead compound to an organomercurial compound in the environment is reported. It must be assumed, that this transalkylation takes place at sites, where organolead compounds occur and Hg2+ is available. Thus, it will be necessary to assess the risk of these sites.

18.
Eur J Clin Microbiol ; 4(5): 483-7, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4065134

RESUMO

Three species of mycobacteria were cultured and processed for cellular fatty acid analysis by capillary gas chromatography in three laboratories to study interlaboratory variations of the resulting chromatographic profiles. Largely consistent and characteristic fatty acid profiles were obtained, although there were minor quantitative variations in the patterns due to methodological differences (cultivation, hydrolysis, derivatization, gas chromatographic conditions etc.). The following points were important for achieving informative and reproducible results. A chemically defined growth medium (e.g., Proskauer-Beck) provides more consistent profiles than the lipid-rich Löwenstein-Jensen medium. Harvesting directly into the digesting solution (NaOH or HCl in methanol) followed by heating or autoclaving is a simple and reliable way of releasing fatty acids. Care should be taken to ensure reproducible detection of long-chain alcohols either by using acid methanolysis or including a base-wash step in the procedure following alkaline hydrolysis. The temperature of the gas chromatographic injector should be at least 325 degrees C. A capillary column of a minimum length of 10 m coated with a methyl silicone is adequate. Our results indicate the possibility of recommending a practical and reproducible gas chromatographic procedure for mycobacterial characterisation.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Mycobacterium/análise , Meios de Cultura , Temperatura
19.
Acta Pathol Microbiol Immunol Scand B ; 90(5): 353-9, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6293245

RESUMO

The fatty acid composition of Bordetella pertussis (13 strains), B. parapertussis (3 strains), B. bronchiseptica (6 strains), Brucella abortus (6 strains), B. melitensis (4 strains) and B. suis (5 strains) was determined. Both genera contained straight-chain saturated and mono-unsaturated acids as well as cyclopropane substituted isomers, but the overall differences between the two genera were distinct. The Brucella species contained exclusively C16 to C19 acids. Minor amounts of hydroxylated acids (tentatively identified as 3-hydroxy-hexadecanoate and 3-hydroxy-octadecanoate) could only be detected after thin-layer chromatography and substantial concentration. The Bordetella species, on the other hand, contained a number of both non-hydroxylated and hydroxylated fatty acids of chain-lengths varying from C10 to C19. Intra-generically, no clear distinction between the Brucella species could be detected. The three species of Bordetella, on the other hand, were clearly distinguished by their fatty acid patterns. B. pertussis did not contain cyclopropane fatty acids encountered in significant amounts in the two other species, and B. bronchiseptica was characterized by containing 2-hydroxy-dodecanoate in significant amounts.


Assuntos
Bordetella/classificação , Brucella/classificação , Ácidos Graxos/análise , Bordetella/análise , Bordetella pertussis/classificação , Brucella/análise , Brucella abortus/classificação , Cromatografia Gasosa
20.
J Gen Microbiol ; 102(1): 33-43, 1977 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-915475

RESUMO

Forty-five strains classified in the family Neisseriaceae were analysed for wax esters by gas-liquid chromatography. The amounts and types of waxes varied between the taxa. Waxes were not detected in 16 strains of 'true neisseriae' (genus Neisseria) or in two strains of Kingella, but they were found in all 'false neisseriae', in all species of Moraxella except Moraxella phenylpyrouvica, in five out of 10 strains of Acintobacter, and in all strains of a group of psychrophilic, oxidase-positive organisms. The chain lengths of the wax esters ranged from C24 to C42, with C36 predominating. In all taxa, esters with even numbers of carbon atoms constituted 70 to 100% of the total. Saturated, mono-unsaturated and diunsaturated waxes were found. Acinetobacter strains were characterized by large amounts (30 to 98%) of di-unsaturated wax esters; such waxes did not exceed 8% in the 'false neisseriae' or Moraxella spp. Waxes of strains belonging to the psychrophilic, oxidase-positive group generally resembled those found in Moraxella. Wax esters with odd numbers of carbon atoms were abundant in M. lacunata (29%), M. atlantae (15%) and in the psychorophilic group (19 to 28%); long-chain esters (C40 or above) were characteristic of M. atlantae (30%) and one strain of M. osloensis (26%).


Assuntos
Neisseriaceae/análise , Ceras/análise , Cromatografia Gasosa , Especificidade da Espécie
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