Salicylate reduces serum insulin concentrations in the rat

Administration of sodium salicylate (50–500 mg/kg, i.p.) reduced serum insulin concentrations in nonfasted rats. This treatment also suppressed the rise in serum insulin that followed oral administration of glucose (by stomach tube) to fasted rats; this effect is only partly attributable to the blunted increase in serum glucose concentrations.     

Use of plasma norepinephrine for evaluation of sympathetic neuronal function in man

Levels of norepinephrine (NE) in human plasma have been determined by a radioenzymatic technique sufficiently sensitive to measure 0.014 ng NE per ml plasma. Several procedures which raise plasma NE levels have been compared and a standard procedure developed to evaluate sympathetic neuronal function based on the increments in plasma NE produced by postural change and a standard amount of exertion. The mean basal level of NE in plasma of 74 resting, supine, normal subjects ranging in age from 10 to 70 (mean 32.7 years) was 0.292 ± 0.016 (± SEM) ng/ml and ranged from 0.112 to 0.738 ng/ml. There was a significant correlation between age and basal levels of NE (L.R. = 0.33, p < 0.01). In 44 subjects who stood for 5 minutes after the basal sample of blood was obtained, the mean plasma level of NE increased to 0.538 ± 0.044 ng/ml and further increased to 0.778 ± 0.080 ng/ml after a subsequent isometric hand grip for 5 minutes.     

Neue Vorstellungen zum Problem der Isoperoxidasen anhand der Trennung durch Disk-Elektrophorese und isoelektrische Fokussierung

Summary Isoelectric focusing (IEF) of peroxidases of different organs and tissues of Nicotiana tabacum L. was performed on thin-layers of Sephadex and polyacrylamide. Isoelectric points (pI's) of peroxidase bands were measured by special electrodes. — The two types of layers showed very similar results. Reproductibility of pI's was better on polyacrylamide. This method is also easier to practise and requires less time than IEF on Sephadex (3 h versus 18). Thus for analytical purposes the acrylamide-technique is preferable, but if it is necessary to regain the separated enzymes it is better to perform IEF on Sephadex. — When IEF-patterns of peroxidase are compared with the disk electrophoresis (DE) patterns of the same tissue, important differences are observed. The 6 bands of G_I (fast migrating, anodic group of DE) are reduced to 2 on the strongly acidic side of IEF (independent of the tissue studied). That means only 2 proteins in G_I can be separated by pI's of the molecules. Maybe the heterogeneity of G_I bands after DE indicates the presence of conformational isomers (conformers). — Because of the reduced number of bands in G_I after IEF there is no difference in the patterns of many tissues (flowers, leaves, shoots, pith) as there is after disk electrophoresis. In the case of G_II (slow migrating, anodic group of DE) on the other hand, there are always 4 different bands after isoelectric focusing in the lower acid region instead of 3 after disk electrophoresis. Disk electrophoresis of peroxidase-groups separated by isoelectric focusing shows the same patterns as direct disk electrophoresis of the extract. The methods produce no artifacts. —Comparison of these results with the peroxidase-patterns of tobacco found by other workers and by other techniques leads to the conclusion that there exist at least 4 isoenzymes of peroxidase corresponding to the 4 groups G_I, G_II, G_III, and G_IV.

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Abkürzungen IEF Isoelektrische Fokussierung - DE Disk-Elektrophorese - pI Isoelektrischer Punkt     

Wall and membrane biogenesis in the unusual labyrinthulid-like organismSorodiplophrys stercorea

Summary Electron microscopic investigations show the scale subunits of the walls ofSorodiplophrys stercorea to be produced by the Golgi apparatus. Their chief monosaccharide subunit is identified tentatively as arabinose. Membrane flow involving the nuclear envelope, endoplasmic reticulum, Golgi apparatus, Golgi vesicles, plasmalemma, and possibly prominent refractive bodies composed of membranes is suggested. Cytochemical data supporting ultrastructural evidence concerning the sites of scale and membrane biogenesis are presented.     

Chromatin structure visualization by immunoelectron microscopy

Antibodies elicited in rabbits by chromatin and by purified histone H2B have been used to study the structure of chromatin by immunoelectron microscopy. Chromatin spread on grids reveals a structure of closely packed spherical particles with an average diameter of 104 Å, arranged either in clusters or in linear arrays of beads, some of which have a supercoil-like arrangement. No DNA strings connecting the beads could be observed. Upon antibody binding, the diameter of the particles increases up to 300 Å. This size is compatible with a model where one layer of gamma globulin molecules 110 Å long encircles a sphere of chromatin 100 Å in diameter. The presence of rabbit gamma globulins on the enlarged beads has been verified by the addition of ferritin-labeled goat anti-rabbit gamma globulins. Anti-chromatin sera which react with nonhistone proteins but not with free histones or DNA react with more than 95% of the beads; this suggests that most of the beads contain nonhistone proteins. Since the number of nonhistone proteins is large, it is improbable that each sphere contains a full complement of these proteins. We therefore suggest that the various chromatin spheres contain different types of nonhistone proteins. About 90% of the chromatin spheres reacted with antibodies to histone H2B, suggesting that most of the chromatin beads contain this type of histone.     

Tuberculous Enteritis

Tuberculous enteritis occurs in about 2 percent of patients with pulmonary tuberculosis. Although it is uncommon in the United States, tuberculous enteritis should be considered in any patient with active pulmonary tuberculosis and abdominal complaints.Eight cases of T. enteritis have been treated at Harbor General Hospital in the last 25 years. Associated pulmonary disease was shown radiologically to be present in seven of eight patients. Findings on contrast studies of the gastrointestinal tract showed disease in six of six patients examined.In five patients, surgical operation was required for diagnosis or complications. Resection of diseased bowel with primary anastomosis was done in five patients. Although medical therapy is the mainstay in the treatment of both pulmonary and intestinal tuberculosis, one staged resection of diseased bowel with primary anastomosis is the procedure of choice for complications such as obstruction, hemorrhage or perforation.     

Linkage of the gene controlling the synthesis of the fourth component of complement to the major histocompatibility complex of the guinea pig

C4-deficient (C4D) guinea pigs are lacking in C4 synthesis, a condition that appears to be caused by a structural gene defect. This defect is inherited as a simple autosomal recessive trait. We have demonstrated linkage between C4D and the major histocompatibility complex of the guinea pig (GPLA). Inbred C4D and inbred strain 13 guinea pigs appear to have the same GPLA haplotype. The use of these two strains should provide an animal model for reconstitution studies of C4 synthesis and for studied exploring the possible role of C4 in cellular and humoral immune responses.Abbreviations used in this paper are C4D deficiency of the fourth component of complement - MHC major histocompatibility complex - GPLA major histocompatibility complex of the guinea pig - MLC mixed lymphocyte culture     

The cytogenetic systems of grasshoppers and locusts

The three endemic species of the Australian genusTolgadia are all distributed in the northern tropical and subtropical areas. They are distinguishable both on morphological and cytological grounds. All three have a derived neo XY, neo XX sex chromosome system involving distinct elements of a basically 11-membered autosome set, namely (spacies-1) (bivittata) and (infirma). Additionallybivittata is homozygous for two autosomal fusions involving and giving 2n=18 as compared to the complement of 2n=22 present in the other two species. Two of the species,bivittata and species-1, have a comparable mean cell chiasma frequency despite their difference in chromosome number. That ofinfirma is significantly higher. Coupled with this, some of the populations ofinfirma are polymorphic for supernumerary heterochromatic segments, principally on the smallest autosome. Such segments increase the mean cell chiasma frequency still further. Thusinfirma, which is the least habitat restricted despite its brachypterous nature, not only has the highest mean cell chiasma frequency but, in addition, has at its disposal a polymorphism capable of magnifying this difference.     

The synthesis of cartilage collagen by rabbit and human chondrocytes in primary cell culture

Summary This report describes a method for preparing primary cell cultures of differentiated rabbit sternal and human vertebral cartilage cells. These cell cultures were shown to synthesize primarily α1 chains, which is taken to mean that at least 82% of the collagen produced is cartilage specific collagen (type II). This work was supported in part by grant HD-05505 from NIH.