Partial characterization of an allergenic glycoprotein from peanut (Arachis hypogaea L.)

A concanavalin A-reactive glycoprotein allergen has been isolated from peanut (Arachis hypogaea). The allergen was separated by affinity chromatography and purified by gel permeation and ion-exchange chromatography. The monomeric molecular weight is 65,000 and the pI is 4.6. The presence of one cysteine residue per molecule results in some dimer formation. Concanavalin A-reactive glycoprotein is a potent allergen for peanut-sensitive patients in both in vivo and in vitro tests. It is allergenically stable, on in vitro examination, at temperatures of up to 100 degrees C and over the pH range 2.8-10. Removal of the carbohydrate moiety failed to eliminate the allergenicity. Concanavalin A-reactive glycoprotein is identified in the crossed immunoelectrophoretic pattern as a major antigen of peanut protein extract but its structural characteristics indicate that it is probably not a component of the major storage-protein complex, arachin.     

Nine demographic factors and their relationship to attitudes toward abortion legalization

The 1967 Gallup Poll on attitudes toward abortion legislation taken for the Population Council was studied by multivariate analysis of 9 demographic factors: age, family income, occupation of household head, race, section of the country, sex, city size, education and religion. The poll was taken in two waves that totaled 6,065 cases (after weighting for a representative sample and elimination of "don't know" and "no answer" responses). The question asked for approval or disapproval of the legalization of abortion for the four "hard" reasons: mother's health, rape, incest, or expected child deformity. The analysis revealed that age, family income, occupation of household head, race, section of the country, and sex did not in themselves have an effect on attitudes towards abortion legalization, though they sometimes were an influence in combination with other variables. Significant statistical correlations were found between approval of abortion legalization and increasing city size and higher educational level. Abortion approval also increases along a religious scale from Jewish-Protestant-Catholic. The most significant theoretical conclusion of the study was that 6 of the 9 factors were not influential on abortion attitudes and the remaining 3 did not have strong predictive-explanatory power as expected. Re-examination of the causes of abortion attitudes is needed.     

Comparison of atenolol and propranolol during insulin-induced hypoglycaemia.

The effects of atenolol, a new beta1-blocking drug, on pulse rate, sweating, and blood glucose levels during insulin-induced hypoglycaemia were studied in a double-blind crossover trial in eight normal subjects using placebo and propranolol as reference agents. The intensity of induced hypoglycaemia was identical for atenolol, propranolol, and placebo. Propranolol prolonged hypoglycaemia, but atenolol did not. Atenolol may therefore be safe for use in patients receiving insulin.     

A 9.6 kb intervening sequence in D. virilis rDNA, and sequence homology in rDNA interruptions of diverse species of Drosophila and other diptera.

A large proportion of the 28S ribosomal RNA genes in Drosophila virilis are interrupted by a DNA sequence 9.6 kilobase pairs long. As regards both its presence and its position in the 28S gene (about two thirds of the way in), the D. virilis rDNA intervening sequence is similar to that found in D. melanogaster rDNA, but lengths differ markedly between the two species. Degrees of nucleotide sequence homology have been detected bewteen rDNA interruptions of the two species. This homology extends to putative rDNA intervening sequences in diverse higher diptera (other Drosophila species, the house fly and the flesh fly), but hybridization of cloned D. melanogaster and D. virilis rDNA interruption segments to DNA of several lower diptera has been negative. As is the case with melanogaster rDNA interruptions, segments of the virilis rDNA intervening sequence hybridize with non-rDNA components of the virilis genome, and interspecific homology may involve these non-rDNA sequences as well as rDNA interruptions. There is, however, evidence from buoyant density fractionation of DNA that the distributions of interruption-related sequences are distinct in D. melanogaster and D. virilis genomes. Moreover, thermal denaturation studies have indicated differing extents of homology between hybridizable sequences in D. virilis DNA and different segments of the D. melanogaster rDNA intervening sequence. We infer from our studies that rDNA intervening sequences are prevalent among higher diptera; that in the course of the evolution of these organisms, elements of the intervening sequences have been moderately to highly conserved; and that this conservation extends in at least two distantly related species of Drosophila to similar sequences found elsewhere in the genomes.     

Discriminant Value of Thyroid Function Tests

Different thyroid function tests permitted a final classification of 204 consecutive patients with suspected thyroid disorders into three populations (thyrotoxic, euthyroid, and hypothyroid). Linear discriminant analysis was applied to all test results (10 variates) on adjacent population pairs. Two invitro tests (serum protein bound iodine (P.B.I.) and tri-iodothyronine (T-3) uptake values) gave good separation of thyrotoxic from euthyroid patients and fairly good distinction of hypothyroid patients. If a ¹³¹I uptake figure was then added to the in-vitro results most patients (95·5%), including thse initially classified as equivocal, were correctly diagnosed. Other tests, including clinical questionnaires, were poor discriminants.Two new techniques of utilizing the test data were devised. Firstly, the data from the two in-vitro tests were also displayed graphically, and oblique boundary lines derived from the discriminant functions gave better separation of patients than previously used limits or mathematical expressions of “free thyroxine.” Secondly, a nomogram incorporating the best four discriminants was designed as a diagnostic aid and proved to be the best means of interpreting the tests.Discriminant analysis of this kind can be used in the interpretation of diagnostic tests in any branch of medicine, and it allows the best use to be made of the available data.     

Comparative base compositions of chloroplast and cytoplasmic tRNAPhe''s from Euglena gracilis.

The nucleoside compositions of chloroplast and cytoplasmic tRNAPhe's from Euglena gracilis have been determined. The modified nucleoside compositions of these two tRNAs indicate that tRNAPheChl is more similar to procaryotic (E. coli) tRNAPhe than to either the Euglena cytoplasmic tRNAPhe or other eucaryotic cytoplasmic tRNAPhe's.     

A note on the kinetics of uptake of d-glucose by the food yeast,Candida utilis

Unlike other yeasts so far investigated, the d-glucose carrier of Candida utilis (strain NCYC 737) appears to change affinity for d-glucose according to its exogenous concentration. When the concentration of d-glucose was <0.4 mM, the apparent K _m 0.2 mM; at >0.4 mM, the K _m 10 mM.     

Enzymic hydrolysis of the carbon–fluorine bond of α-d-glucosyl fluoride by rat intestinal mucosa: Localization of intestinal maltase

1. alpha-d-Glucosyl fluoride was hydrolysed by an extract of rat intestinal mucosa. The pH optimum was 6.6 and the K(m) 0.4mm at 20 degrees . Activity was assayed by release of either glucose or fluoride. 2. The alpha-d-glucosyl fluoride-hydrolase activity of the extract was associated with both mutarotase and alpha-d-glucosidase activities. 3. Tris (5mm) inhibited both the alpha-d-glucosidase and alpha-d-glucosyl fluoride-hydrolase activities by 55% but did not inhibit mutarotase. The K(i) of tris for both enzyme activities was 2mm. 4. The extract did not hydrolyse melibiose and lactose. Mutarotase used both alpha-d-glucose and beta-l-arabinose as substrates but the glucosyl fluoride-hydrolase activity did not extend to beta-l-arabinosyl fluoride. 5. The thermal stability of alpha-d-glucosidase and alpha-d-glucosyl fluoride hydrolase was identical. Mutarotase was more thermolabile. 6. A preparation of the brush border of intestinal epithelial cells contained both alpha-d-glucosyl fluoride-hydrolase and alpha-d-glucosidase activities. In each precipitate and washing the ratio of the two activities was the same. All the mutarotase activity was in the first supernatant. 7. Agidex, a fungal amyloglucosidase, cleaved glucosyl fluoride in addition to maltose. Tris inhibited both activities and in each case the K(i) was 3mm. 8. The probable identity of alpha-d-glucosyl fluoride hydrolase with alpha-d-glucosidase is discussed and a possible mechanism for the reaction suggested. 9. Incubation of intestinal slices with alpha-d-glucosyl fluoride led to complete hydrolysis in 30min. The glucose rapidly entered the cell and was metabolized, leaving the fluoride in the incubation medium. This constitutes a further proof that the intestinal alpha-d-glucosidase, although on the brush border, is located outside the site of active transport of sugars.