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61.
Norimasa Sugita 《PloS one》2016,11(11)
A recent focus of interest has been on the functional significance of genital licking (fellatio and cunnilingus) in relation to sexual selection in Pteropodid bats. In the present paper, a form of fellatio in wild Bonin flying foxes, Pteropus pselaphon, performed between adult males has been reported. During the mating season, adult flying foxes roost in same-sex groups, forming ball-shaped clusters which provide warmth. The female clusters may also contain a few males. Unassociated with allogrooming, same-sex genital licking occurred among males in the all male clusters. As such, male-male fellatio can be considered as homosexual behavior, two functional explanations could account for this behavior; the social bonding and the social tension regulation hypotheses suggested in a previous review. Given that neither the simpler alternative that in all male groups such fellatio may represent misdirected sexual behavior, nor the two previously proposed functional hypotheses were supported by the data, I propose another functional hypothesis. Homosexual fellatio in this species could help males solve inconsistent situations in the roost when there are conflicts between cooperative behavior for social thermoregulation and competition for mating. 相似文献
62.
63.
Zsolt Radak Shuzo Kumagai Hideko Nakamoto Sataro Goto 《Journal of applied physiology》2007,102(4):1696-1701
Oxoguanine DNA glycosylase (OGG1) and uracil DNA glycosylase (UDG) are two of the most important repair enzymes that are involved in the base excision repair processes to eliminate oxidative damage from mammalian DNA, which accumulates with aging. Red and white skeletal muscle fibers have very different antioxidant enzyme activities and resistance to oxidative stress. In this paper, we demonstrate that the activity of OGG1 is significantly higher in the red type of skeletal muscle compared with white fibers from old rats. Exercise training resulted in increased OGG1 activity in the nuclei of red fibers and decreased activity in nuclei of white fibers and in the mitochondria of both red and white fibers. The activities of UDG were similar in both red and white muscle fibers. Exercise training appears to increase the activity of UDG in the nuclei and mitochondria. However, exercise training affects the activity of OGG1 in nuclei and mitochondria differently, suggesting different regulation of the enzymes. In contrast, UDG showed similar activities in nuclei and mitochondrial extracts of exercise-trained animals. These data provide evidence for differential regulation of UDG and OGG1 in maintaining fidelity of DNA in oxidatively stressed cells. 相似文献
64.
Characterization of a new phosphonocerebroside, N-methyl-2-aminoethylphosphonylglucosylceramide, from the antarctic krill, Euphausia superba 总被引:1,自引:0,他引:1
S Itonori K Kamemura K Narushima N Sonku O Itasaka T Hori M Sugita 《Biochimica et biophysica acta》1991,1081(3):321-327
A novel phosphonglycosphingolipid was purified from the whole tissue of the antarctic krill, Euphausia superba by successive column chromatography on DEAE- and QAE-Sephadex and silicic acid (Iatrobeads). The structure was elucidated by means of IR, FAB-MS, 1H-NMR, GC and GC-MS analyses of the water-soluble products after complete and partial acid hydrolysis, and methylation analysis of a product of hydrogen fluoride degradation; it was identified to be a phosphonocerebroside, 6'-O-(N-methyl-2-aminoethylphosphonyl)Glcp beta 1----1ceramide. The ceramide moiety was composed of tetradecasphingenine and octadecasphingatriene as the main sphingoids, and monounsaturated C22- and C24-acids and their 2-hydroxy homologues as the major fatty acids. 相似文献
65.
66.
Effective selection system for generating marker-free transgenic plants independent of sexual crossing 总被引:17,自引:0,他引:17
In a previous report, a novel selection protocol termed "the MAT-vector system" for generating marker-free transgenic plants
(MFTPs) was presented. The first stage of the system is visual selection of morphologically abnormal transgenic shoots, ipt-shooty, that have lost apical dominance and rooting ability. The second stage involves elimination of the ipt gene and the appearance of MFTPs free of ipt gene influence. The present report describes a practical MAT-vector in which removal of the ipt gene is efficiently mediated by the site-specific recombination system R/RS from Zygosaccharomyces rouxii, in place of the maize transposable element Ac, used previously. This improved MAT-vector produced MFTPs from 39% of moderate ipt-shooty and 70% of extreme ipt-shooty lines. These results are superior to the previous MAT-vector which produced MFTPs from only 5% of ipt-shooty lines. The present novel system also induced direct development of MFTPs from adventitious buds without production
of ipt-shooty intermediates. The presence of β-glucuronidase (GUS) and neomycin phosphotransferase (NPTII) genes of interest, and
the absence of the ipt gene were verified by a GUS histochemical assay, NPTII assay, and molecular analysis.
Received: 19 June 1998 / Revision received: 4 December 1998 / Accepted: 18 December 1998 相似文献
67.
Effects of Chronic Administration of Interferon α A/D on Serotonergic Receptors in Rat Brain 总被引:7,自引:0,他引:7
The effects of chronic administration of interferon (IFN; recombinant human IFN -A/D) on serotonergic binding sites in rat brain were investigated. IFN was injected daily for 2 weeks at a dose of 100000 I.U./kg, (i.p.) in male Wistar rats. IFN did not alter either [3H]ketanserin binding to 5-HT2A receptors or [3H]paroxetine binding to 5-HT transporters. Scatchard analysis of [3H]8-hydroxy-dipropylaminotetraline (8-OH-DPAT) binding to 5-HT1A receptors demonstrated the presence of high- and low-affinity binding sites in both treatment and control groups. IFN significantly increased both Kd and Bmax measures of [3H]8-OH-DPAT binding at low-affinity binding sites, but not at the high-affinity sites. These results suggest that IFN affects the low-affinity 5-HT1A receptors sites and may be involved in the development of IFN-induced psychiatric disturbances. 相似文献
68.
Chloroplast phylogeny indicates that bryophytes are monophyletic 总被引:3,自引:0,他引:3
Nishiyama T Wolf PG Kugita M Sinclair RB Sugita M Sugiura C Wakasugi T Yamada K Yoshinaga K Yamaguchi K Ueda K Hasebe M 《Molecular biology and evolution》2004,21(10):1813-1819
Opinions on the basal relationship of land plants vary considerably and no phylogenetic tree with significant statistical support has been obtained. Here, we report phylogenetic analyses using 51 genes from the entire chloroplast genome sequences of 20 representative green plant species. The analyses, using translated amino acid sequences, indicated that extant bryophytes (mosses, liverworts, and hornworts) form a monophyletic group with high statistical confidence and that extant bryophytes are likely sisters to extant vascular plants, although the support for monophyletic vascular plants was not strong. Analyses at the nucleotide level could not resolve the basal relationship with statistical confidence. Bryophyte monophyly inferred using amino acid sequences has a good statistical foundation and is not rejected statistically by other data sets. We propose bryophyte monophyly as the currently best hypothesis. 相似文献
69.
Iwama T Hosokawa H Lin W Shimizu H Kawai K Yamagata S 《Bioscience, biotechnology, and biochemistry》2004,68(6):1357-1361
The oah2 gene homologous to the oah1 of Thermus thermophilus HB8 was cloned and sequenced. It comprised 1,236 bp encoding a protein of 412 amino acid residues and was overexpressed. The gene product, also having O-acetyl-L-homoserine sulfhydrylase (EC 4.2.99.10) activity, was purified to homogeneity and characterized comparatively with the oah1 product. The two proteins shared many characteristics. 相似文献
70.
We successfully isolated a novel aerobic chemolithotrophic sulfur-oxidizing bacterium, designated strain SO07, from wastewater biofilms growing under microaerophilic conditions. For isolation, the use of elemental sulfur (S(0)), which is the most abundant sulfur pool in the wastewater biofilms, as the electron donor was an effective measure to establish an enrichment culture of strain SO07 and further isolation. 16S rRNA gene sequence analysis revealed that newly isolated strain SO07 was affiliated with members of the genus Halothiobacillus, but it was only distantly related to previously isolated species (89% identity). Strain SO07 oxidized elemental sulfur, thiosulfate, and sulfide to sulfate under oxic conditions. Strain SO07 could not grow on nitrate. Organic carbons, including acetate, propionate, and formate, could not serve as carbon and energy sources. Unlike other aerobic sulfur-oxidizing bacteria, this bacterium was sensitive to NaCl; growth in medium containing more than 150 mM was negligible. In situ hybridization combined with confocal laser scanning microscopy revealed that a number of rod-shaped cells hybridized with a probe specific for strain SO07 were mainly present in the oxic biofilm strata (ca. 0 to 100 micro m) and that they often coexisted with sulfate-reducing bacteria in this zone. These results demonstrated that strain SO07 was one of the important sulfur-oxidizing populations involved in the sulfur cycle occurring in the wastewater biofilm and was primarily responsible for the oxidation of H(2)S and S(0) to SO(4)(2-) under oxic conditions. 相似文献