RESUMO
Using guanine nucleotides, pertussis toxin, and specific antisera against the COOH-terminals of the alpha-subunits of Gi1/2, Gi3, and G(o), the binding and biological response of the Y2 receptor (Y2R) for peptide YY (PYY) was probed in SMS-KAN neuroblastoma cells. The specific binding of radiolabeled PYY exhibited a single apparent dissociation constant, KD = 76 pM for intact cells and KD = 906 pM for permeabilized cells. However, other data suggested existence of multiple receptor affinity states. A shift in KD and a decrease in apparent number of binding sites (Bmax) was observed in permeabilized cells when incubated with guanine nucleotides. By contrast, in membrane preparations guanine nucleotides induced only a decrease in Bmax. In intact cells, agonist exposure inhibited the intracellular accumulation of forskolin-stimulated cyclic AMP by 80% (IC50 = 420 nM) compared with 94% inhibition (IC50 = 380 nM) in permeabilized cells. In permeabilized cells, preincubation with antisera against alpha i1/2 and alpha i3 blocked the functional response of PYY, with anti-alpha i3 being the most potent; whereas anti-alpha o failed to affect the cyclic AMP levels. These results suggest that permeabilized SMS-KAN cells serve as a good model system for analysis of Y2R binding kinetics and functional response and that the Y2R interacts directly with several different GiS (but not G(o)).
Assuntos
Proteínas de Ligação ao GTP/metabolismo , Neuroblastoma/metabolismo , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Permeabilidade da Membrana Celular , AMP Cíclico/metabolismo , Proteínas de Ligação ao GTP/imunologia , Nucleotídeos de Guanina/farmacologia , Humanos , Soros Imunes/imunologia , Membranas Intracelulares/metabolismo , Cinética , Neuroblastoma/patologia , Peptídeo YY , Peptídeos/farmacologia , Toxina Pertussis , Células Tumorais Cultivadas , Fatores de Virulência de Bordetella/farmacologiaRESUMO
The essential oil from the herb PLATOSTOMA AFRICANUM was analysed by means of GLC, LSC and GC-MS. So far a large number of its components were identified, among which were 16 sesquiterpene hydrocarbons (43%), seven phenylpropane derivatives (16%), seven oxygen-containing, straight-chain aliphatic compounds (11%), and six oxygen-containing sesquiterpenes (5%). Monoterpenes were present in small amounts only. An estimated 10% of the total oil was made up of diterpenes. The main component of the oil was germacrene-D (19%). An unusual component was found to be the chromene derivative precocene I (11%), which is an insect anti-juvenile hormone. This is, as far as we know, the first detection of a chromene in the family Lamiaceae. The composition of the oil of P. AFRICANUM has not been reported previously. The method of isolation affected the yield, composition, and odour of the oil.
RESUMO
Commencing on 1.1.1987, all requests for access to case records were registered prospectively in all of the Copenhagen County Hospitals. In the Copenhagen County Hospital, Nordvang, 103 requests were made for access to the case records in the course of 1987. Ninety-five requests in the adult departments resulted in complete access in 90 cases, limited access in one case while access was refused in three cases. One person making the request did not turn up. Eight requests concerning patients in the child psychiatric department resulted in complete access in one case, limited access in five cases while access was refused in two cases. This corresponds to 3.0% in the departments for child psychiatry and 2.7% in the departments for adults. No deterioration in health was observed in any of the 97 cases where access was permitted. In many cases, insight into the case records may, on the other hand, be a good therapeutic measure. On two cases only, access to the case records was given to a third person with the patient's permission, and the majority of the patients did not request a copy of the case records but accepted access to the case records in the form of the right to read the case records with assistance, if necessary. It is concluded that in the first year after introduction of the Danish legislation concerning access to the case records, this ran very smoothly with fewer difficulties than anticipated in a large psychiatric hospital in the region of the capital.
Assuntos
Psiquiatria Infantil , Hospitais de Condado , Hospitais Públicos , Prontuários Médicos , Defesa do Paciente , Psiquiatria , Criança , Dinamarca , HumanosRESUMO
A modified, simple method for screening of fresh plant material for glycosidic bound volatile compounds is described. The plant material is "stabilized" in boiling water, possible occurring volatile compounds removed by hydrodistillation, the remaining aqueous extract treated with beta-glucosidase, and the volatile compounds, liberated by the enzymatic hydrolysis, isolated and analysed by gas chromatography. In MELISSA OFFICINALIS and MENTHA SPICATA relatively large amounts of glycosidic bound eugenol and some aliphatic alcohols were found, but only small amounts of such monoterpene alcohols occurring in the volatile oils.
RESUMO
Treatment of suspension cultures of some Tabernaemontana species (Apocynaceae) with elicitors (e.g. cellulase, Candida albicans) result in a rapid de novo production of antimicrobial active triterpenes. The triterpenes are identified as ursene carboxylic acid derivatives. These triterpenes are not produced by an elicited cell suspension culture of Catharanthus roseus, another Apocynaceae.
RESUMO
The essential oil of OCIMUM GRATISSIMUM, growing wild in Rwanda, was investigated by LSC, GLC, and GC-MS. The oil contained 35% thymol and 11% eugenol, which may indicate the occurrence of a new chemotype of the species. A large amount of hydrocarbons (42%) including 18% P-cymene was also found. The oil showed a relatively strong antimicrobial effect. The oil of O. GRATISSIMUM, cultivated in Rwanda from seeds collected in Cameroon, consisted of 47% thymol and only 0.3% eugenol. This sample contained 49% hydrocarbons, including 23% gamma-terpinene. Most of the constituents detected in the oil samples were not previously known to be present in the essential oil of O. GRATISSIMUM.
RESUMO
A procedure is described for the extraction of both anthraquinones and alkaloids from tissue culture material of CINCHONA species. Using this extraction method, it is possible to quantitatively determine the two groups of secondary metabolites produced in CINCHONA tissue cultures.
RESUMO
From Tabernaemontana chippii root bark, forty-five alkaloids were isolated; thirty-four were fully characterized by means of their spectral data and/or co-tlc; eight alkaloids were new, four of them being 3-hydroxy derivatives of known dimeric voacamine type alkaloids. Most of the twenty-six known alkaloids belonged to the corynanthean, ibogan, or bisindole classes. The structures of eleven other alkaloids--all minor--were only partially elucidated, most of them being new alkaloids. All the dimeric alkaloids were shown to possess strong antimicrobial activity against gram-positive bacteria and moderate to weak activity against gram-negative bacteria.
Assuntos
Alcaloides/farmacologia , Bactérias/efeitos dos fármacos , Plantas Medicinais/análise , Alcaloides/análise , Antifúngicos/farmacologia , Fenômenos Químicos , Química , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Leveduras/efeitos dos fármacosRESUMO
The essential oil of OCIMUM KILIMANDSCHARICUM Guerke, growing wild in Rwanda, was investigated by LSC, GLC and GC-MS. The oil contained 62% 1.8-cineole, indicating the occurrence of a new chemotype of the species concerned. In addition to 1.8-cineole, 16 oxygen-containing compounds and 14 monoterpene hydrocarbons were identified, of which limonene and beta-pinene were the main components. Most of the constituents were not previously known to be present in the essential oil of O. KILIMANDSCHARICUM.
RESUMO
From the stem bark of STRYCHNOS SPINOSA two tertiary alkaloids were isolated. By means of their spectral data they were identified as 11-methoxy-diaboline and 12-hy-droxy-11-methoxy-diaboline.
RESUMO
Studies were performed on the alkaloid content of leaf and stem callus cultures of CINCHONA PUBESCENS Vahl with respect to the influence of plant growth regulators and light. The same alkaloids were found in the analysed tissues - with some quantitative differences. In general, a medium containing zeatin: 1 microM and 2,4-dichlorophenoxyacetic acid: 1 microM gave a higher alkaloid production than a medium containing benzyladenine: 8.1 microM and 2,4-dichlorophentoxy acetic acid: 4.5 microM. The alkaloid production in the unorganized callus cultures was stimulated by light. Anthraquinones were found in all tissue cultures.
RESUMO
The essential oil from fruits of HERACLEUM PERSICUM Desf., growing wild in Iran, was investigated by means of LSC, GLC and GC-MS. Co-chromatography of synthesized compounds was also applied for identification of components. The oil contained about 95% of aliphatic esters, 4% of aliphatic alcohols and 1% of monoterpenes; 37 esters and 17 monoterpenes were identified.
RESUMO
In extracts from roots of CAPNOPHYLLUM PEREGRINUM Z-ligustilide was found to be present and in similar extracts of PEUCEDANUM OSTRUTHIUM cnidilide, Z-ligustilide and senkyunolide were detected. The compounds were analyzed by TLC, GLC and GCMS.
RESUMO
The taxonomy, phytochemistry, ethnobotany, and pharmacology of the genus Tabernaemontana L. (Apocynaceae) is reviewed. The genus is currently being revised taxonomically; most of the segregate genera are being reunited with it and the number of species that will ultimately be recognized will probably be about 100. All the names encountered in the chemical and ethnobotanical literature have been evaluated as far as possible, and a list is presented of the recognized species and their synonyms. The biogenesis and classification of the indole alkaloids found in Tabernaemontana species is set out and some problems in the determination of their stereochemistry are discussed. To facilitate access to the information, three lists have been compiled: the alkaloids in alphabetical order; the alkaloids in order of increasing molecular weight; and the alkaloids grouped according to their biogenetic classification, together with the species and plant part(s) in which they are known to occur. Biogenetic and chemotaxonomic aspects are briefly considered. A table of the non-alkaloidal constituents is also included. The ethnobotany of individual Tabernaemontana species is outlined and an overall assessment made. Likewise, information on the pharmacology of crude extracts and individual alkaloids from Tabernaemontana species has been assembled and appraised.
Assuntos
Plantas Medicinais , Alcaloides/biossíntese , Animais , Botânica , Fenômenos Químicos , Química , Humanos , Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais/classificação , Plantas TóxicasRESUMO
The (1)HNMR (CDCl (3)) data on 28 tetrahydroprotoberberine alkaloids have shown that it is possible, from the chemical shift values observed for the aromatic protons, not only to determine the substitution pattern but also the type of substituents carried on the two sites in rings A and D within this class of alkaloids.
RESUMO
A phytochemical investigation of the tertiary phenolic alkaloidal fraction of the stems of CHASMANTHERA DEPENDENS H OCHST. (Menispermaceae) has yielded the tetrahydroprotoberberine type alkaloids govanine ( identical with(-)-tetrahydropseudocolumbamine) [1] and coreximine [2]; the pavine type alkaloid bisnorargemonine [3] and the morphinandienone type alkaloid pallidine [4].
RESUMO
Revised structure 8 is proposed for the quaternary bisbenzylisoquinoline alkaloid phaeantharine, based on spectrometric data. Phaeantharine, which occurs in Phaeanthus ebracteolatus (fam. Anonaceae), has current interest as a potential insecticide. Phaeantharine also exhibits moderate activity against gram-positive bacteria.