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1.
Phytochemistry ; 50(1): 135-8, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9891937

RESUMEN

The structure of a new triterpenoid saponin, frondoside D, isolated from Cucumaria frondosa has been determined principally by high field 1D and 2D NMR and FAB-MS spectrometry. Frondoside D was shown to be 3 beta-[3-O-methyl-O-beta-D-glucopyranosyl-(1-3)-O-beta-D- xylopyranosyl-(1-4)-[O-beta-D-xylopyranosyl-(1-2)]-O-beta-D- quinovopyranosyl-(1-2)-O-beta-D-4-sulfonatoxylo-pyranosyl]-1 6 beta-acetoxy-23S-hydroxy-holost-7-ene, sodium salt.


Asunto(s)
Saponinas/química , Pepinos de Mar/química , Triterpenos/química , Animales , Conformación de Carbohidratos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Saponinas/aislamiento & purificación , Espectrometría de Masa Bombardeada por Átomos Veloces , Triterpenos/aislamiento & purificación
2.
J Nat Prod ; 58(11): 1759-66, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8594154

RESUMEN

Six new [1-4, 7, 9] and two known [6 and 8] metabolites have been isolated from culture filtrates of conifer endophyte strains of Canoplea elegantula. Their structures have been determined by spectroscopic means. Compound 1 was toxic to spruce budworm cells, and both 1 and 3 were toxic to spruce budworm larvae.


Asunto(s)
Cumarinas/química , Insecticidas/química , Plantas Tóxicas/química , Animales , Canadá , Cumarinas/aislamiento & purificación , Cumarinas/toxicidad , Insecticidas/aislamiento & purificación , Insecticidas/toxicidad , Larva
3.
J Nat Prod ; 55(1): 93-101, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1602303

RESUMEN

The structures of a novel sulfated saponin, frondoside B (C59H92O31S2M2) [5], and frondecaside (C58H92O63S6M6) [6], a unique hexasulfated decasaccharide, have been deduced by nmr (500 MHz) methods. Based on 1H COSY, relay COSY, NOESY, and 13C-nmr data, frondoside B was shown to have the structure 3 beta-O-(3-O-methyl-beta-D-glucopyranosyl-(1----3)-O-beta-D-6- sulfonatoglucopyranosyl-(1----4)-O-[beta-D-xylopyranosyl-(1----2)] -O-beta- D-quinovopyranosyl-(1----2)-O-beta-D-4-sulfonatoxylopyranosyl++ +)-holost-7-ene sodium (or potassium) salt. From 1H-COSY, relay COSY, 13C-nmr data, T1 measurements, and comparison with nmr spectra of frondoside B, the structure of frondecaside was established as 3-O-methyl-6-sulfonato-beta-D-glucopyranosyl-(1----3)-O-beta-D-6- sulfonatoglucopyranosyl-(1----4)-O-[beta-D-xylopyranosyl-(1----2)] -O-beta- D-quinovopyranosyl-(1----2)-O-beta-D-4-sulfonatoxylopyranosyl++ +-(1----1)-3-O- methyl-6-sulfonato-beta-D-glucopyranosyl-(1----3)-O-beta-D-6- sulfonatoglucopyranosyl-(1----4)-O-[beta-D-xylopyranosyl-(1----2)] -O-beta- D-quinovopyranosyl-(1----2)-O-beta-D-4-sulfonatoxylopyranoside+ ++ sodium (or potassium) salt.


Asunto(s)
Oligosacáridos/aislamiento & purificación , Saponinas/aislamiento & purificación , Pepinos de Mar/química , Sulfatos/aislamiento & purificación , Animales , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Oligosacáridos/química , Saponinas/química , Sulfatos/química
4.
J Anat ; 177: 127-34, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1769887

RESUMEN

The attachment zones of the meniscal horns of 7 dissecting room cadavers were examined by routine histology. All the knees were devoid of gross pathological change and no discoid menisci were included. Significant differences are reported in the thickness of the zones of uncalcified fibrocartilage and cortical calcified tissue (calcified fibrocartilage and underlying lamellar bone) and in the percentage of bone:bone marrow. There was a thicker zone of uncalcified fibrocartilage and a greater quantity of calcified tissue at the horns of the lateral than the medial meniscus. The differences in uncalcified fibrocartilage were largely attributable to the posterior horns, but the variations in calcified tissue mainly reflected differences between the anterior horns. It is suggested that the greater mobility of the lateral meniscus and the blending of its anterior horn with the anterior cruciate ligament are important factors accounting for the quantitative differences in the meniscal attachment zones.


Asunto(s)
Meniscos Tibiales/anatomía & histología , Anciano , Anciano de 80 o más Años , Médula Ósea/anatomía & histología , Huesos/anatomía & histología , Calcificación Fisiológica , Cartílago/anatomía & histología , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
J Nat Prod ; 47(5): 815-8, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6512534

RESUMEN

The novel ester (E)-phytol (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate++ + (1); (6Z,9Z,12Z,15Z)-hexadecatetraenoic acid; (6Z,9Z,12Z,15Z)-octadecatetraenoic acid; and (6Z,9Z,12Z)-hexadecatrienoic acid isolated from the diatom Navicula delognei f. elliptica, show significant antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhimurium, and Proteus vulgaris. beta-Carotene, alpha-cryptoxanthin, fucoxanthin, lutein, trans-phytol, and plastoquinone-9 were also isolated from this diatom.


Asunto(s)
Antibacterianos/aislamiento & purificación , Bacterias/efectos de los fármacos , Eucariontes/análisis , Antibacterianos/farmacología , Fenómenos Químicos , Química , Hidrólisis
6.
Steroids ; 44(3): 261-5, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6152642

RESUMEN

Nine 5 alpha, 8 alpha-epidioxy delta 6 and delta 6,9(11) sterols were identified including the hitherto unknown (22E)-5,8-epidioxy-5 alpha, 8 alpha-stigmasta-6,9(11),22-trien-3 beta-ol 9 from the sea anenome Metridium senile based on 200 MHz 1Hnmr and mass spectral data.


Asunto(s)
Cnidarios/análisis , Peróxidos/análisis , Anémonas de Mar/análisis , Esteroles/análisis , Animales
7.
Cell Tissue Res ; 220(3): 623-36, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7028271

RESUMEN

Gerbils were divided, on the basis of body weight, into obese (greater than 80 gms) and lean (less than 80 gms) groups. Fasting blood glucose estimations on all 31 gerbils, and glucose tolerance tests on 9 lean and 6 obese animals, were carried out. All lean and some obese gerbils were normoglycaemic and other obese were hyperglycaemic. All obese gerbils exhibited glucose intolerance. General morphological studies were undertaken as follows: (i) assessment of mesenteric fat deposits, (ii) measurement of anterior abdominal wall thickness, (iii) ratio of animal length to width at specified loci (index of shape). The degree of obesity was less than previously reported in this species though blood glucose abnormality was comparable. The index of animal shape showed a strong correlation with body weight. The following kinds of histological observation were made on pancreases from 4 lean and 4 obese gerbils: (i) % islet representation, (ii) islet size distribution, (iii) beta-cell granularity, (iv) islet vascularity, (v) islet/duct association, (vi) proportions of alpha- and D-cells, (vii) glycogen deposition in islet and duct cells. The pancreases of obese gerbils contained a higher proportion of islet tissue than those of lean due to generally larger islets: this hyperplasia was mainly attributable to beta-cell proliferation. Many obese gerbil islets exhibited hyperaemia and beta-cell degranulation. There was no evidence of glycogen deposition.


Asunto(s)
Glucemia , Gerbillinae/anatomía & histología , Islotes Pancreáticos/citología , Obesidad/patología , Animales , Gránulos Citoplasmáticos/ultraestructura , Femenino , Gerbillinae/sangre , Prueba de Tolerancia a la Glucosa , Glucógeno/análisis , Hiperemia , Islotes Pancreáticos/análisis , Masculino , Obesidad/sangre
8.
Acta Anat (Basel) ; 108(4): 446-62, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6168162

RESUMEN

The histology and cell types of the islets of Langerhans were studies in the Mongolian gerbil during post-natal development using granule stains, fluorescence methods and electron microscopy. Relative islet volume, islet size distribution, islet-duct association, islet-fat association, alpha- and D cell populations and the size distribution of secretion granules in islet cells were quantified. In adult gerbils islets have an elliptical profile enclosed by a thin collagenous capsule, a central core of beta-cells, a peripheral shell of alpha-cells and an incomplete layer of D cells between. In animals of 1 week or less, islets lack a capsule, are poorly vascularized and not innervated, though alpha, beta- and D cells are present. alpha-Cells exhibit green fluorescence during these early stages that disappears when adrenergic nerve fibres grow into the islets. Electron microscopy shows a fourth (unidentified) granular islet cell type, and small granular cells, that probably correspond to intensely fluorescent cells, were found within islets and neuroinsular complexes.


Asunto(s)
Gerbillinae/anatomía & histología , Islotes Pancreáticos/citología , Factores de Edad , Animales , Dopamina/análisis , Islotes Pancreáticos/crecimiento & desarrollo , Islotes Pancreáticos/ultraestructura , Microscopía Electrónica , Serotonina/análisis , Coloración y Etiquetado
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