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2.
Phytochemistry ; 130: 77-84, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27406893

RESUMO

Liverworts are a rich source of a diverse array of specialized metabolites, such as terpenoids and benzenoids, which are potentially useful for pharmaceutical or agrochemical applications, and also provide clues to elucidate the strategy by which liverworts adapt to the terrestrial environment. Liverworts, belonging to orders Marchantiales and Jungermanniales, possess oil bodies. In Marchantia polymorpha L., oil bodies are confined to scattered idioblastic oil body cells. It has been assumed that the specialized metabolites in M. polymorpha specifically accumulate in the oil bodies in oil body cells; however, no direct evidence was previously available for this specific accumulation. In this study, direct evidence was obtained using micromanipulation techniques coupled with MS analysis that demonstrated the specific accumulation of sesquiterpenoids and marchantin A in the oil body cells of M. polymorpha thalli. It was also observed that the number of oil body cells increased in thalli grown in low-mineral conditions. The amounts of sesquiterpenoids and marchantin A detected in crude extract prepared from the whole thallus were roughly proportional to the number of oil body cells found in a given volume of thallus, suggesting that oil body cell differentiation and sesquiterpenoid and marchantin A biosynthetic pathways are coordinated with each other.


Assuntos
Bibenzilas/isolamento & purificação , Éteres Cíclicos/isolamento & purificação , Marchantia/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Bibenzilas/química , Éteres Cíclicos/química , Gotículas Lipídicas , Estrutura Molecular
3.
Phytochemistry ; 56(3): 297-312, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11243454

RESUMO

Bryophytes contain a large number of terpenoids and phenolic compounds. Recent topics relating to the chemical constituents found in 36 Japanese, 3 New Zealand, 2 European, 1 Argentinean and 1 Taiwanese liverworts and 2 Japanese mosses and their biological activity are discussed. The chemosystematics of some liverworts as well as the chemical relationship between liverworts and mosses, and bryophytes and ferns are also discussed.


Assuntos
Bibenzilas/química , Furanos/química , Lactonas/química , Plantas/química , Terpenos/química , Bibenzilas/farmacologia , Furanos/farmacologia , Lactonas/farmacologia , Especificidade da Espécie , Terpenos/farmacologia
4.
Phytochemistry ; 56(4): 347-52, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11249099

RESUMO

A new peroxy muurolane-type sesquiterpenoid was isolated from the ether extract of the Belgium liverwort Scapania undulata, together with three known ent-muurolanes. A new lepidozane-type sesquiterpenoid was isolated from the Japanese Porella subobtusa together with a known santalane- and two africane-type sesquiterpenoids. All structures were determined by means of NMR spectroscopic techniques. The chemosystematics of each species are discussed.


Assuntos
Diterpenos/isolamento & purificação , Plantas/química , Sesquiterpenos/isolamento & purificação , Diterpenos/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Plantas/classificação , Sesquiterpenos/química
5.
Phytochemistry ; 56(8): 807-10, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11324908

RESUMO

A 2,3-seco-cuparane-type sesquiterpenoid and the previously known barbatane-type sesqui- and ent-kaurane-type diterpenoids were isolated from the Japanese liverwort Jungermannia infusca (Mitt.) Steph. The structure of the 2,3-seco-cuparane-type sesquiterpenoid was determined by NMR spectroscopic analyses.


Assuntos
Plantas/química , Sesquiterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Sesquiterpenos/química
6.
Phytochemistry ; 55(3): 247-53, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11142851

RESUMO

Seven herbertane-type sesquiterpenoids, 1,13-dihydroxyherbertene, 1,14-dihydroxyherbertene, 1,15-dihydroxyherbertene, 12-methoxyherebertene-1,2-diol, herberteneacetal, herbertenone A and herbertenone B were isolated from the Japanese liverwort Herbertus sakuraii, together with four known herbertane- and three dimeric herbertane-type sesquiterpenoids and ent-pimara-8(14),15-dien-19-oic acid. Their structures were elucidated by spectroscopic methods. H. sakuraii is chemically similar not only to H. aduncus but also to the Mastigophora species.


Assuntos
Plantas Medicinais/química , Sesquiterpenos/isolamento & purificação , Plantas , Sesquiterpenos/química
7.
Phytochemistry ; 53(2): 271-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10680182

RESUMO

Four pinguisane type sesquiterpenes were isolated from the liverwort Trocholejeunea scandvicensis, together with three aromatic compounds. The structures of the cited compounds were established on the basis of spectroscopic means. The first two compounds were new sesquiterpenes, while the other compounds were previously isolated from other liverworts and lichen sp., respectively. The stereochemistry for lejeuneapinguisanolide was determined by X-ray analysis, a possible biosynthetic pathway to it was postulated. The other new sesquiterpene is lejeuneapinguisenone.


Assuntos
Plantas Medicinais/química , Sesquiterpenos/química , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Extratos Vegetais/química , Sesquiterpenos/isolamento & purificação
8.
Phytochemistry ; 57(4): 499-506, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11394847

RESUMO

The hydrocarbon fraction of the liverwort Trocholejeunea sandvicensis was investigated. Four new sesquiterpene hydrocarbons including the trifaranes (-)-trifara-9,14-diene (6) and (-)-3,7-di-epi-3,7-trifara-9,14-diene (7), as well as (+)-sandvicene (8), a sesquiterpene with uncommon skeleton, and the rearranged trifarane sesquiterpene (+)-neotrifaradiene (9) were isolated and their structure elucidated. A biogenetic pathway for the four compounds is proposed, with nerolidol as their common precursor.


Assuntos
Hidrocarbonetos/química , Extratos Vegetais/análise , Plantas Medicinais/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética
9.
Phytochemistry ; 54(5): 455-60, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10939348

RESUMO

Two metabolites were obtained by microbial transformation of a furanosesquiterpene alcohol, dehydropinguisenol, using Aspergillus niger and Aspergillus cellulosae. Their structures were established as 10-oxo-lejeuneapinguisenol and lejeuneapinguisenol on the basis of their spectroscopic data. The latter compound was obtained after 4 and 9 days of incubation with A. cellulosae at 30 degrees C and 25 degrees C, respectively. Aspergillus niger produced both metabolites after 3 and 5 days incubation at 30 degrees C, respectively. A possible pathway for the formation of these compounds is discussed here together with their antimicrobial activity against A. niger and A. cellulosae.


Assuntos
Aspergillus/metabolismo , Sesquiterpenos/metabolismo , Aspergillus niger/metabolismo , Biotransformação , Cinética , Magnoliopsida , Estrutura Molecular , Sesquiterpenos/química
10.
Phytochemistry ; 53(5): 593-604, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10724186

RESUMO

Two new pinguisane-type, three new Diels-Alder reaction-type dimeric pinguisane sesquiterpenoids and known sesqui and diterpenoids were isolated from the ether extract of the Japanese liverwort Porella acutifolia subsp. tosano. Their absolute stereostructures were established by a combination of extensive 2D-NMR, CD spectra, X-ray crystallographic analysis, modified Mosher's method and chemical correlation.


Assuntos
Plantas Medicinais/química , Sesquiterpenos/química , Dicroísmo Circular , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Plantas Medicinais/classificação , Estereoisomerismo
11.
Phytochemistry ; 55(2): 131-40, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11065289

RESUMO

Nine plant growth inhibitors were isolated from the tropical weed Sphenoclea zeylanica, which shows allelopathic properties. Those compounds hitherto not reported from any plant source were the isomers of cyclic thiosulfinate, (1S,3R,4R)-(+)- and (1R,3R,4R)-(+)-4-hydroxy-3-hydroxymethyl-1,2-dithiolane-1-oxides, and (2R,3R,4R)-(-)- and (2S,3R,4R)-(+)-4-hydroxy-3-hydroxymethyl-1,2-dithiolane-2-oxides. These were named zeylanoxide A, epi-zeylanoxide A, zeylanoxide B and epi-zeylanoxide B, respectively. The absolute configurations at C-3 and C-4 were elucidated by chemical synthesis of both enantiomers from L- and D-glucose. Two of the inhibitors were secologanic acid and secologanoside. and three other inhibitors were by known secoiridoid glucosides formed as artifacts during extraction with methanol. The cyclic thiosulfinates and secoiridoid glucosides completely inhibit the root growth of rice seedlings at 3.0 mM. While the specific activity of the inhibitors was not high, since they accumulated to circa 0.61% S. zelanica by dry weight, this suggests that the inhibitors are nervertheless potent allelochemicals in this weed.


Assuntos
Magnoliopsida/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Lactuca/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia , Análise Espectral
12.
J Neurosurg ; 94(2 Suppl): 302-4, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11302636

RESUMO

The authors describe the case of an 18-year-old man who presented with complaints of weakness and paresis in his arms following an injury. Radiological examination demonstrated an aneurysmal bone cyst of C-6. The patient underwent a two-stage operation. Satisfactory results were obtained after complete resection of the lesion, laminoplasty, and anterior fusion without placement of instrumentation. The authors consider a two-stage operation supplemented by fusion without instrumentation to be the best treatment for young patients with aneurysmal bone cysts occurring at C-6.


Assuntos
Cistos Ósseos Aneurismáticos/diagnóstico , Cistos Ósseos Aneurismáticos/cirurgia , Vértebras Cervicais , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/cirurgia , Adolescente , Cistos Ósseos Aneurismáticos/complicações , Cistos Ósseos Aneurismáticos/patologia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Descompressão Cirúrgica , Humanos , Imageamento por Ressonância Magnética , Masculino , Lesões do Pescoço/complicações , Reoperação , Compressão da Medula Espinal/etiologia , Doenças da Coluna Vertebral/complicações , Doenças da Coluna Vertebral/patologia , Tomografia Computadorizada por Raios X
13.
Resuscitation ; 48(3): 275-8, 2001 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-11278093

RESUMO

This study investigated the cause for needing airway maneuvers to maintain a patent airway during the use of cuffed oropharyngeal airway (COPA). Twenty adult patients (29.4+/-6.8 years-old, ASA 1-2) scheduled for minor gynecological surgery who required brief manipulations of the airway despite COPA use following the manufacture's guidelines, were enrolled in this study. To obtain airway patency, 15 patients required only the head-tilt maneuver. In eight of the 15 patients, the laryngeal inlet was opened partially (n=4) or completely (n=4). Despite lifting the epiglottis, the laryngeal inlet was incomplete at the level of pharyngeal view. The patency of the laryngeal inlet was decided by the extent of the distance between the posterior pharyngeal wall and the lateral glossoepiglottic fold, which was made by hyoid bone. In the other seven patients, the head-tilt maneuver elevated the epiglottis and completely opened the laryngeal inlet. Five patients required both the jaw-thrust and head-tilt maneuver. Of these patients lifting the epiglottis was incomplete in three and the laryngeal inlet was partially collapsed in one even after the airway manipulations. The airways in these three patients, however, became patent after manipulations despite the persisting partial obstruction.


Assuntos
Obstrução das Vias Respiratórias/etiologia , Anestesia por Inalação/instrumentação , Anestesia por Inalação/métodos , Máscaras Laríngeas , Adulto , Estatura , Peso Corporal , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Masculino
14.
Int J Radiat Biol ; 70(5): 517-20, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8947532

RESUMO

We developed a method for detecting chromosomal aberrations after irradiation with high doses of gamma-rays. At high dose levels, few of the irradiated cells are able to enter mitosis so that it is difficult to obtain enough mitotic chromosomes using a conventional colcemid block. Therefore, okadaic acid was used to condense prematurely the chromosomes of interphase cells. Even after irradiation with doses > 40 Gy, okadaic acid was able to force sufficient numbers of cells to condense their chromosomes. Segments of chromosomes were then detected by chromosome painting using a gold-conjugated antibody followed by silver enhancement. This simple method allows highly damaged chromosomes to be detected with great sensitivity.


Assuntos
Aberrações Cromossômicas , Cromossomos/efeitos da radiação , Raios gama , Imuno-Histoquímica , Ciclo Celular , Células Cultivadas , Cromossomos/efeitos dos fármacos , Cromossomos/fisiologia , Demecolcina/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Linfócitos , Ácido Okadáico/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Doses de Radiação
15.
Arch Dermatol Res ; 281(4): 227-30, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2774654

RESUMO

A Ginkgo biloba L. fruit extract was prepared and purified. Three groups of guinea pigs were sensitized to the crude extract, anacardic acids 1, and cardanols 2 respectively, using the FCAT method, and the fourth group to urushiol using the epicutaneous route. Each group was tested for reaction to the primary sensitizer and to the different main aromatic compounds isolated from Ginkgo fruits. Anacardic acids were found to be good sensitizers, while cardanols failed to induce allergic contact dermatitis (ACD). No cross-reactions were observed among the compounds tested. Ginkgolic acids 1 seem to be the main allergens of Ginkgo biloba L. and the hypothesis of a biotransformation of 1 into catechol 4 is not supported by experiment.


Assuntos
Catecóis , Dermatite de Contato , Extratos Vegetais/análise , Animais , Feminino , Cobaias , Hipersensibilidade Tardia , Plantas Tóxicas , Testes Cutâneos
16.
Arch Dermatol Res ; 274(3-4): 277-81, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6891888

RESUMO

Guinea pigs were sensitized to polygodial 1, a natural sesquiterpene dialdehyde, using intradermal injections in Freund's complete adjuvant. Cross-reactions with a (+/-)-mixture of warburganal and (-)-warburganal 2 (a natural hydroxylated derivative of polygodial) showed a high specificity of the allergic response since the (-)-pseudoenantiomer (having the same configuration as the primary sensitizer) gave a stronger skin reaction than the racemic mixture.


Assuntos
Alérgenos/toxicidade , Dermatite Atópica/induzido quimicamente , Dermatite de Contato/imunologia , Hipersensibilidade a Drogas/diagnóstico , Extratos Vegetais/toxicidade , Plantas Medicinais , Sesquiterpenos/toxicidade , Animais , Fenômenos Químicos , Química , Reações Cruzadas , Dermatite Atópica/imunologia , Feminino , Cobaias , Hipersensibilidade Tardia/induzido quimicamente , Hipersensibilidade Tardia/diagnóstico , Testes Intradérmicos
17.
J Pharm Sci ; 68(7): 928-30, 1979 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-458621

RESUMO

The biotransformation of dl-camphene in rabbits was investigated. Four neutral metabolites, 6-exo-hydroxycamphene, 10-hydroxycamphene, and diastereoisomers of camphene-2,10-glycol, were identified and two alcohols, 7-hydroxycamphene and 3-hydroxytricyclene, were estimated by IR, UV, NMR, and mass spectra and chemical degradations. The formation of these compounds can be explained through a homoallylic oxidation or an epoxide formation.


Assuntos
Canfanos/metabolismo , Animais , Biotransformação , Canfanos/urina , Masculino , Coelhos
18.
J Pharm Sci ; 70(4): 406-15, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7229954

RESUMO

The biotransformation of (+)-, (-)-, and (+-)-alpha-pinenes, (-)-beta-pinene (nopinene), (-)-cis-pinane, (+)-3-carene, (-)-cis-carane, myrcene, and p-cymene in rabbits was investigated. The major metabolites were as follows: (-)-trans-verbenol from (+)-, (-)-, and (+/-)-alpha-pinenes; (-)-10-pinanol and (-)-1-p-menthene-7,8-diol from (-)-beta-pinene; (-)-alpha-terpineol and (-)-trans-sobrerol from (-)-cis-pinane; (-)-m-mentha-4,6-dien-8-ol, 3-caren-9-ol, (-)-3-carene-9-carboxylic acid, and 3-carene-9,10-dicarboxylic acid from (+)-3-carene; carane-9,10-dicarboxylic acid from (-)-cis-carane; and myrcene-3(10)-glycol, myrcene-1,2-glycol, uroterpenol, and p-cymene-9-carboxylic acid from p-cymene. These metabolisms include allylic oxidation, epoxidation, stereoselective gem-dimethyl hydroxylation and its oxidation, cleavage of a conjugated double bond by epoxidation, and regioselective oxidation, some of which are not found usually in chemical reactions, and due to which various new compounds were determined. This biotransformation of the monoterpene hydrocarbons gave some insect pheromones in high yield.U


Assuntos
Monoterpenos , Terpenos/metabolismo , Monoterpenos Acíclicos , Animais , Monoterpenos Bicíclicos , Biotransformação , Compostos Bicíclicos com Pontes/metabolismo , Cimenos , Masculino , Coelhos
19.
J Pharm Sci ; 79(6): 540-7, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2395101

RESUMO

The seven metabolites of (+)-dehydroabietic acid (DHA) were newly isolated from rabbit urine by liquid chromatography. On the basis of chemical and spectral data their structures were established to be (15S)-8,11.13-abietatrien-16,18-dioic acid, 2 alpha-hydroxy-8,11,13,15-abietatetraen-18-oic acid, (15R)-15,16-dihydroxy-8,11,13-abietatrien-18-oic acid, 2 beta,15-dihydroxy-8,11,13-abietatrien-18-oic acid, (15S)-2 beta,16-dihydroxy-8,11,13-abietatrien-18-oic acid, 2 alpha,15-dihydroxy-8,11,13-abietatrien-18-oic acid, and (15S)-2 alpha,16-dihydroxy-8,11,13-abietatrien-18-oic acid. The possible hydroxylation routes of DHA in rabbits and the difference between the metabolism of DHA in microorganisms and that in rabbits are discussed.


Assuntos
Abietanos , Diterpenos/metabolismo , Animais , Biotransformação , Diterpenos/análise , Diterpenos/urina , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Coelhos
20.
Int J Biol Macromol ; 28(5): 381-5, 2001 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-11325425

RESUMO

The extra domain A containing fibronectin (EDA(+)FN) concentration in plasma of rheumatoid arthritis (RA) is abnormally higher than the normal level. We synthesized various gellan-sulfate (GS) candidates as artificial ligands for removing EDA(+)FN from plasma. The interaction between these artificial ligands and EDA(+)FN was evaluated using affinity constants (KA), which were determined by surface plasmon resonance measurement. The KA (3.6 x 10(8) per M) of GS-25 [degree of substitution for sulfonation (DS) = 25%] with EDA(+)FN was higher than those of other molecules: GS-16 (DS=16%) at 8.3 x 10(7) per M, and GS-35 (DS = 35%) at 1.7 x 10(8) per M. Furthermore, GSs displayed selectivity of EDA(+)FN for binding with plasma FN (KAEDA(+)FN)/KA(plasma FN)>2). The removal ratio in plasma was measured by using GS-immobilized gel. Removals of 66, 11, 7.7, 6.2, 6.9, and 12% for EDA(+)FN, plasma FN, fibrinogen, albumin, immunoglobulin G (IgG) and antithrombin III from the patient-model plasma were, respectively, achieved with GS-25-immobilized gel. These results suggest that GS may be used as a selective artificial ligand for EDA(+)FN removal from plasma in RA treatment.


Assuntos
Proteínas Sanguíneas/química , Fibronectinas/sangue , Fibronectinas/química , Ligantes , Polissacarídeos Bacterianos/química , Adsorção , Humanos , Ressonância de Plasmônio de Superfície
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