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741.
E-64, L-trans-epoxysuccinyl-leucylamido (4-guanidino) butane, a specific inhibitor of thiol proteases originally isolated from a culture broth of fungi, and its synthetic analogues, were examined for immune responses to the splenocytes of BDF1 mice. In the cultures of 2-day-primed splenocytes of the mice, E-64 and its close analogues, increased the number of direct splenic hemolytic plaque forming cells (PFC). In addition, it was demonstrated that E-64 enhanced the PFC responses in the mice. These results suggested that some thiol proteases might be involved in the immune response process in mice.  相似文献   
742.
The intracellular function of a specific protein to protect lysosomal beta-galactosidase and neuraminidase activities against proteases in human fibroblasts was studied. Beta-Galactosidase was purified from human placenta to different degrees; a preparation (A) contained also two concomitant proteins, and a highly purified preparation (B) contained only the mature beta-galactosidase. The protein concentrate of the culture medium of normal fibroblasts restored the activities of the deficient enzymes, beta-galactosidase and neuraminidase, in galactosialidosis cells. This effect was inhibited only by the anti-A anti-serum, and not by the anti-B antiserum. A 46-kilodalton protein, secreted from fibroblasts cultured in the presence of ammonium chloride, was detected again only by the anti-A antiserum, and not by the anti-B antiserum. It was concluded that this protein has a function to restore their activities in fibroblasts from galactosialidosis patients after being endocytosed from the culture medium.  相似文献   
743.
Summary The ontogenetic apperance of pineal photo-receptors was compared with that of retinal photoreceptors in the ayu Plecoglossus altivelis and the lefteye flounder Paralichthys olivaceus, which hatched 10 days and 3 days after fertilization, respectively. Despite the disparity in incubation time, the outer segments (containing membranous lamellae) of the pineal photoreceptors first appeared from 3 to 4 days after fertilization in both species. In contrast, the outer segments of the retinal photoreceptors first became visible 5 to 6 days after fertilization, although a characteristic retinal stratification and the optic tract leaving the ganglion cell layer were already found 4 days after fertilization in both species. The functional significance of these temporal disparities and/or similarities in photoreceptor development are discussed with special reference to the timing of daily rhythmic activities during the early developmental period of the teleosts.The results were presented at the Annual Meeting of the Japanese Society of Scientific Fisheries on April 2, 1990 (Tokyo)  相似文献   
744.
Brain Cell Biology - The main and accessory olfactory epithelia of the mouse are composed of many cell populations. Each sensory neuron is thought to express one allele of one of the ~1000...  相似文献   
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Several mutant cDNAs of elongation factor 2 (EF-2) were constructed by site-directed mutagenesis and their products expressed in mouse cells were investigated. Amino acid substitution for the histidine residue of codon 715, which is modified post-translationally to diphthamide, resulted in non-functional EF-2 and this substitution did not render EF-2 resistant to Pseudomonas aeruginosa exotoxin A, which inactivates EF-2 transferring ADP-ribose to the diphthamide residue. These non-functional EF-2s with replacements of the histidine-715 residue showed various extents of inhibition of protein synthesis by competing with functional EF-2 in vivo. These results suggest that histidine-715 is essential for the translocase activity of EF-2 and that the region around diphthamide functions in recognition of, and/or binding to ribosomes. Substitution of proline for the alanine-713 residue and substitution of glutamine for the glycine-717 residue converted EF-2 to partially toxin-resistant forms. Two-dimensional gel analysis with fragment A of diphtheria toxin of these toxin-resistant EF-2s revealed that their ADP-ribosylations by toxin were much less than that of wild-type EF-2.  相似文献   
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We reviewed Coram et al. (Biodivers Conserv 30:2341–2359, 2021, https://doi.org/10.1007/s10531-021-02196-6), a paper that highlights the use of social media data to understand marine litter and marine mammals in Southeast Asia. While we commend its intent, we find that the methodology used and conclusions drawn portray an incomplete and inaccurate perception of how strandings, stranding response, and analysis of stranding data have been conducted in the region. By focusing on investigative results revealed by a very limited search of one social media platform (Facebook), using only English keywords, and insufficient ground-truthing, Coram et al. (2021) have, unintentionally, given the perception that Southeast Asian scientists have not conducted even the bare minimum of investigation required to better understand the issue of marine litter and its impact on marine mammals. In this commentary we provide a more accurate account of strandings research in Asia and include recommendations to improve future studies using social media to assess conservation issues.

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