A temperature sensitive mutant of BHK21, tsBN2, showed a premature chromosome condensation (PCC) upon the temperature shift of 40.5 degrees, even in the absence of DNA replication. The induction of PCC requires new protein synthesis, but not necessarily new RNA synthesis. Our data suggested that the messenger RNA for chromosome condensation starts to be transcribed at the beginning of S phase. At the permissive temperature (33.5 degrees), the messenger RNA for chromosome condensation translated with a very slow rate during S phase and rapidly in G2-M phase. At the nonpermissive temperature (40.5 degrees), however, those messenger RNAs were translated anytime, so that various figures of PCC appeared depending on the cell cycle. On the way of PCC induction, ribosomal RNA synthesis was inhibited at first, as expected from mitosis. Our data suggested that the synthesis of protein(s) for chromosome condensation was regulated by the post-transcriptional mechanism, in which tsBN2 might be defective, especially at the translational level.

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In the present study, we investigated how brain images affect metacomprehension judgments of neuroscience research. Participants made a prereading judgment of comprehension of the text topic and then read a text about neuroimaging findings. In Experiment 1, participants read text only or text accompanying brain images. In Experiment 2, participants read text accompanying bar graphs or text accompanying brain images. Then participants were asked to rate their comprehension of the text. Finally, they completed comprehension tests. The results of Experiment 1 showed that the text accompanying brain images was associated with higher metacomprehension judgments than was the text only, whereas the performance of the comprehension test did not differ between each condition. The results of Experiment 2 showed that the text accompanying brain images was associated not only with credibility of the text, but also with higher metacomprehension judgments than was the text accompanying the bar graphs, whereas the performance of the comprehension test did not differ between each condition. The findings suggest that the readers' subjective judgments differ from actual comprehension.

Two lectins have been isolated from leaves of Aloe arborescens Mill by salt precipitation, pH-dependent fractionation and gel filtration. One lectin (P-2) has a molecular weight of approximately 18,000, consists of two subunits (alphabeta) and contains more than 18% by weight of neutral carbohydrate. The smaller subunit (alpha) has a molecular weight of approximately 7,500 and the larger subunit (beta) a molecular weight of approximately 10,500. The other lectin (S-1) has a molecular weight of approximately 24,000, consists of two subunits (gamma2) with a molecular weight of approximately 12,000 and contains more than 50% by weight of neutral carbohydrate. An interesting feature of the amino acid compositions of these lectins is the high proportion of acidic amino acids, such as aspartic acid and glutamic acid, and the low proportion of methionine and histidine. S-1 has a strong hemagglutinating activity. On the other hand, P-2 has not only hemagglutinating activity but also mitogenic activity on lymphocytes, precipitate-forming reactivity with serum proteins, one of which is alpha2-macroglobulin, and complement C3 activating activity via the alternate pathway.