Neurophysiologic analysis of the critical period of delay of a reinforcing stimulus in the dog

At interval of less than 100 ms between indifferent sound and unconditioned electrocutaneous stimulation, classical defensive conditioned reflex is not elaborated in dogs, in full correspondence with literature data. But intracortical temporary connection is established; this fact is shown by electrographic phenomena, the most specific and demonstrative among them is "conditioned evoked potential". The absence of behavioural (peripheral) and presence of electrographic (central) manifestations allow to assume that for the formation of the conditioned reflex of full value the involvement is necessary of additional activational (motivational) mechanisms, connected with reticular and (or) limbic subcortical structures which do not react to the conditioned stimulus at time deficit in conditions of microdelay.     

Conformational analysis of acetyl-L-phenylalanine p-acetyl and p-valeryl anilides

Empirical force-field calculations and ir and ¹H-nmr spectra indicate that five-membered (C₅) and seven-membered (C) hydrogen-bonded rings are the preferred conformations of acetyl-L -Phe p-acetyl and p-valeryl anilides in nonpolar media. The C₅/C ratio was found to be dependent on the dryness of the solute and the solvent. This fact and the results from conformational-energy calculations suggest that a molecule of water participates in the stabilization of the C conformation.     

Solid-Phase Radioimmunoassay for Substance P

The solid-phase immunoassay for quantification of substance P has been developed. The assay is based on the repartition of anti-substance P antibodies between the insoluble phase-immobilized substance P and the free peptide. The immobilized substance P-antibody complex is then quantified with 125I-protein A. The method allowed detection of 10 pg of substance P. The values of substance P concentration obtained by the present method in different regions of the rat brain were comparable to those obtained by standard radioimmunoassay with 125I-tyr-8-substance P as tracer. The described solid-phase radioimmunoassay is a simple, sensitive, and reliable technique for quantification of substance P-like immunoreactivity in biological samples.     

Sequences hybridizing to mRNA, oligo(dT) and dsRNA from pre-mRNA are contiguous in the cloned mouse DNA fragments.

Fragments from the DNA of mouse embryos produced by restriction endonucleases HindIII were cloned in pBR322 plasmid and examined for the ability to hybridize in situ with [32P] labeled cDNA synthesized from the polysomal poly(A)+mRNA template. Several of the selected clones were examined for the presence of specific sequences inside the cloned mouse DNA fragments by the blotting procedure of southern [1]. The data obtained indicate that the majority of the cloned mouse DNA fragments contained sequences hybridizing with cDNA, oligo(dT) and double-stranded regions from pre-mRNA. The results of hybridization experiments and double digestion with HindIII+HaeIII endonucleases provide evidence that these sequences could be contiguous in the given restriction DNA fragments.     

Repetitive sequences in nuclear deoxyribonucleic acid ofSaccharomyces cerevisiae

Nuclear DNA isolated from aSaccharomyces cerevisiae ρ mutant was studied for the presence of repetitive sequences. A main-band DNA preparation free of rRNA genes and 2-μm plasmid DNA was prepared by density gradient centrifugation in Cs₂SO₄−Ag⁺. A fast renaturing fraction was obtained from this mainband DNA by 3 cycles of reassociation at a low C₀t value (0.2). This fraction reassociated 10 times faster than the bulk of the main-band DNA. Its sequences comprised about 3% of the genome and showed a considerable heterogeneity in respect to repetitiveness. The relationship of this fraction to the repetitive transposable elements recently found in yeast cells is discussed.     

Features of the biosynthesis of immunoglobulin G peculiar to the growth process

It is established that with partial hepatectomy, Shvets leukosis and hepatoma RS-1 the biosynthesis intensity of rat blood serum proteins producing aggregates in the acid medium is considerably higher than that of other serum proteins, the incorporation of the radioactive precursor into immunoglobulin G peculiar to intensive normal and malignant growth being particularly intensive. During liver regeneration as well as in malignant growth specific radioactivity of immunoglobulin G peculiar to the growth processes is three and five times, respectively, as high as this value for blood serum soluble proteins and proteins of alpha-globulin fractions.     

Aliphatic composition of cutin from inner seed coat of apple

Lithium aluminum deuteride reduction released aliphatic monomers from the inner seed coat fraction but not from the outer seed coat fraction of mature apples. These monomers were identified by GC/MS and the results indicate that the inner coat of apple seed contains a cutin polymer with the major monomer acids being 18-hydroxyoctadec-9-enoic (31%), 9,10-epoxy-18-hydroxyoctadecanoic (28%) and 9,10,18-trihydroxyoctadecanoic (20 %). The monomer composition of this seed coat cuticular polymer was very similar in seeds taken from freshly harvested fruit and in those taken from fruit which had been stored at 4° for 6 months.     

Composition and structure of secondary fatty alcohols and ketones,isolated from Pyrus malus skin wax

A homologous series of long-chain secondary fatty alcohols from C₂₁ to C₂₉ (C₂₉ being Predominant) has been isolated from the skin wax of a Bulgarian apple variety, Bouhavitsa. The alcohols were found only in a free state. Long-chain fatty ketones, with C₂₉ again markedly prevalent, have been isolated for the first time from the skin wax of this, and another variety, Tetovka. The C₂₉-ketone from both samples was identified by means of MS as nonacosan-10-one. A complete similarity has been found in the relative amounts of C₂₉ in the mixtures of secondary alcohols, ketones and paraffins.     

New Pogonophora from the Atlantic and Pacific Oceans

A study of a collection of Pogonophora, made by the R.V. "Vema" in the Atlantic and Pacific Oceans, has revealed a total of 20 species. One of these, Lamellisabella ivanovi, was already known, the rest appear to be new. Seven species are described in detail, the others being represented only by tubes or insignificant fragments.     

Fingerprint Patterns in Huntington's Chorea and Parkinson's Disease

In the course of a continuing search for means of predicting Huntington''s chorea before the onset of neurological symptoms, a study of fingerprint patterns was undertaken, using the technique employed by Hodges and Simon in the investigation of patients with Wilson''s disease. Fingerprint patterns of 61 patients with Huntington''s chorea and 50 with Parkinson''s disease were compared with norms established by Scotland Yard. Although an increased incidence of the “whorl” pattern was seen in the left second and third fingers in patients with Huntington''s chorea, this finding could not be interpreted as having diagnostic or prognostic value as it was found also in some normal subjects and in occasional cases of Parkinson''s disease. The pattern supposedly characteristic of Wilson''s disease was also seen in persons with Huntington''s chorea.