Lymphadenosis benigna cutis: pseudomalignant form and its imprint smear cytology

Two cases of lymphadenosis benigna cutis or lymphocytoma showing pseudomalignant histologic features have been studied with the imprint smear method and histochemical technique for α-naphthyl esterase. The present study revealed the presence of lymphoblasts and more immature lymphocytic cells (so-called Germinoblasten and basophile Stammzellen of <i>Lennert) </i>as well as reticulum cells showing several variations.

In vivo uncoating of tobacco mosaic virus after infection of tobacco leaves

In vivo uncoating of tobacco mosaic virus (TMV) was studied. As Shaw had reported, initiation of uncoating reaction takes place very efficiently. Coat protein is removed from the virus as a peptide which is precipitable with trichloroacetic acid. Short rod particles with partly exposed RNA are thus formed. Further uncoating to coat protein‐free TMV‐RNA (28S) seems to take place with very low efficiency which is comparable to that of formation of local lesions on the inoculated leaf. From the data on the intracellular distribution of these products of uncoating reaction, mechanisms and significance of these reactions are discussed.

Crystals from cocoons of Malacosoma neustria testacea

The crystalline material covering the cocoon of Malacosoma neustria testacea (Lasiocampidae, Lepidoptera) was analyzed physically and chemically. The mean component was identified as calcium oxalate monohydrate, and the crystals were found to be whewellite in form.

Ocular dominance and perceptual asymmetry

Two experiments were performed to determine the relation of sighting and acuity dominance to tachistoscopic recognition. In both, single-letter material was exposed binocularly to either the left or right of fixation at brief durations. In Exp. I ( N = 32) visual field differences in recognition were unrelated to sighting dominance. The results of Exp. II ( N = 24) suggested that both acuity dominance and cerebral dominance affect visual field differences. While all were strongly right-handed (and presumably left cerebral-dominant), right acuity-dominant Ss displayed a large right-field superiority, whereas left acuity-dominant Ss exhibited no visual field difference. These results suggest an interaction between acuity dominance and cerebral dominance which may be mediated by the relative superiority of the crossed optic pathways.

Reactivities of actin as a contractile protein

The molecular basis for the mechanism of contraction in striated muscle, with primary emphasis on the interaction between the thick and thin filaments and the role of the thin (actin) filaments, is the theme presented. Recent information relating to actin-myosin interaction points up the fact that definitive statements cannot be made regarding the molecular interaction(s) that lead to contraction. Nevertheless, the properties of actin indicate that (a) actin in the monomeric state has properties differing markedly from actin in the polymer (filament) state; (b) these property differences may be significant in the contractile process, for they include changes in the reactivity of the bound nucleotide and actin-myosin complex formation; (c) the bound nucleotide seems to be required in the contraction process. For these, and other, reasons discussed, the tentative hypothesis is advanced that the contraction reaction involves local changes in the actin filament providing local monomer or monomer-like actin units in the reaction with myosin.