The configurations at C-24 of 24-alkylsterols of six samples of Clerodendrum species (Verbenaceae) - the aerial parts of C. fragrans, C. inerme, C. infortunatum, C. scandens, and C. siphonanthus, and the seeds of C. infortunatum - were examined by NMR. All samples contained 24 beta-ethylsterols possessing a delta 25-bond, clerosterol and 22-dehydroclerosterol, as the dominant sterol components. The other 24-ethylsterols lacking a delta 25-bond, 24-ethyl-22-dehydrocholestanol, 24-ethylcholesterol, and 24-ethyl-22-dehydrocholesterol, which were present as minor components, were shown to be mixtures of the 24 alpha- and 24 beta-epimers, with the 24 alpha-epimers predominating in all cases. Four minor 24-methyl-sterols, 24-methylcholestanol, 24-methylcholesterol, 24-methyl-22-dehydrocholesterol, and 24-methyllathosterol, were shown to be C-24 epimeric mixtures, whereas two others, 24-methyl-22,25-bisdehydrocholesterol and 24-methyl-22-dehydrolathosterol, were found to be present only as the 24 beta-epimers. This is the first report of the occurrence of 24 beta-ethyl-22-dehydrocholestanol in higher plants.

Chemical Phenomena↗

PubMedDate not supplied

Proteoglycan chemistry of the intervertebral disks.

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Adolescent↗

PubMedDate not supplied

Collagens, elastin and noncollagenous protein of the intervertebral disk.

This is a review of the recent developments in collagens, elastin, and noncollagenous protein of the normal and abnormal intervertebral disk. Much progress has been made on the chemistry of the normal disk constituents. However, little work has been done to date on the essential lesion of the early degenerative disk in humans; a major effort in this field is indicated in the next decade. The reasons are obvious, for in the unraveling of the etiology of degeneration of the intervertebral disk lies the hope and expectation of prevention of disk failure.

Chemical Phenomena↗

PubMedDate not supplied

Biomechanics and biochemistry of the intervertebral disks: the need for correlation studies.

The literature on the biomechanics of the intervertebral disk is reviewed with emphasis on biomechanical--biochemical--morphological correlative studies. The deficiency of definitive correlative studies is apparent and an appeal is made to interested investigators to fill in the voids in this extremely important area of study. A comprehensive theory of intervertebral disk failure awaits application of existing biomechanical, biochemical and morphological techniques in a detailed and methodical manner to the normal and early degenerative human intervertebral disks.

Animals↗

PubMedDate not supplied

Distribution of glycosaminoglycans across the normal and the scoliotic disc.

This paper reports on our investigations of the glycosaminoglycans (GAGs) (hyaluronic acid, chondroitin-6-sulfate, and keratan sulfate) of 13 adjacent zones of normal and scoliotic discs obtained at necropsy. The isolation and separation of these GAGs on the microgram scale was achieved using the different solubilities of the calcium and cetyl pyridinium chloride complexes. In normal discs the distribution of these GAGs is symmetric about the nucleus pulposus where their concentration is highest, and lowest in the outer annulus regions. A shift in this distribution profile was observed for the GAGs of the scoliotic discs, particularly at the apex of the curve. On the concave side of this disc the chondroitin-6-sulfate was elevated relative to discs at a lower level. In those annulus zones on the convex side of the curve, the keratan sulfate and hyaluronic acid levels were elevated and chondroitin sulfate depressed. These results suggest the presence in these respective regions of at least two different species of proteoglycans accompanied by elevated hyaluronate levels.

Adolescent↗

PubMedDate not supplied

A novel activity cage for rats: characterization of some phenylethylamine derivatives with central stimulant and depressant effects.

1. A novel activity cage for rats is described. Eight light beams are aimed at a light-conducting perspex rod at the centre of a cylindrical cage. The photoresistor at the end of the rod detects the changes in light intensity produced by interruption of the light beams. 2. The apparatus is simple to operate and was capable of detecting small differences in the motor activity of groups of rats. 3. Dose-dependent increases in motor activity were produced by dexamphetamine (1.36 to 27.3 mumol/kg, i.p.). The depressant effects produced by 20 mumol/kg doses of nonfenfluramine were greater than those of fenfluramine. Large doses (100 mumol/kg) of tranylcypromine stimulated motor activity whereas its cis-isomer, cis-2-phenylcyclopropylamine, depressed motor activity.

Animals↗

PubMedDate not supplied

Anorectic and motor activity effects of some 1-benzylcycloalkylamines in the rat.

1. A series of 1-benzylcycloalkylamines with cycloalkyl rings of five, six or seven carbons and with various benzyl ring substituents (3-Cl, 4-Cl, 4-F, 3-CF3) was prepared and tested for anorectic and motor activity effects in rats. 2. Two potent, non-stimulant, anorectics were found: 1-(3-chlorobenzyl)-cycloheptylamine, and its N-methyl analogue. The activity of these compounds resembled that of chlorphentermine.

Amines↗