163 research outputs found
Parameter fitting in three-flavor Nambu--Jona-Lasinio model with various regularizations
We study the three-flavor Nambu--Jona-Lasinio model with various
regularization procedures. We perform parameter fitting in each regularization
and apply the obtained parameter sets to evaluate various physical quantities,
several light meson masses, decay constant and the topological susceptibility.
The model parameters are adopted even at very high cutoff scale compare to the
hadronic scale to study the asymptotic behavior of the model. It is found that
all the regularization methods except for the dimensional one actually lead
reliable physical predictions for the kaon decay constant, sigma meson mass and
topological susceptibility without restricting the ultra-violet cutoff below
the hadronic scale.Comment: 22 pages, 10 figure
Changes in the Collagen Binding Property of Human Plasma Fibronectin with Aging
We investigated changes in quality of plasma fibronectin with aging, especially in the interaction of fibronectin with collagen, using an enzyme-linked immunosorbent assay. When fibronectin isolated from the plasma of young people was compared with that from old people, the latter was found to bind poorly to gelatin, Type I and Type III collagens. No differences in molecular weight were detected between the two types of fibronectin by SDS-polyacrylamide gel electrophoresis
A structural constraint for functional interaction between N-terminal and C-terminal domains in simian immunodeficiency virus capsid proteins
<p>Abstract</p> <p>Background</p> <p>The Gag capsid (CA) is one of the most conserved proteins in highly-diversified human and simian immunodeficiency viruses (HIV and SIV). Understanding the limitations imposed on amino acid sequences in CA could provide valuable information for vaccine immunogen design or anti-HIV drug development. Here, by comparing two pathogenic SIV strains, SIVmac239 and SIVsmE543-3, we found critical amino acid residues for functional interaction between the N-terminal and the C-terminal domains in CA.</p> <p>Results</p> <p>We first examined the impact of Gag residue 205, aspartate (Gag205D) in SIVmac239 and glutamate (Gag205E) in SIVsmE543-3, on viral replication; due to this difference, Gag<sub>206-216 </sub>(IINEEAADWDL) epitope-specific cytotoxic T lymphocytes (CTLs) were previously shown to respond to SIVmac239 but not SIVsmE543-3 infection. A mutant SIVmac239, SIVmac239Gag205E, whose Gag205D is replaced with Gag205E showed lower replicative ability. Interestingly, however, SIVmac239Gag205E passaged in macaque T cell culture often resulted in selection of an additional mutation at Gag residue 340, a change from SIVmac239 valine (Gag340V) to SIVsmE543-3 methionine (Gag340M), with recovery of viral fitness. Structural modeling analysis suggested possible intermolecular interaction between the Gag205 residue in the N-terminal domain and Gag340 in the C-terminal in CA hexamers. The Gag205D-to-Gag205E substitution in SIVmac239 resulted in loss of in vitro core stability, which was recovered by additional Gag340V-to-Gag340M substitution. Finally, selection of Gag205E plus Gag340M mutations, but not Gag205E alone was observed in a chronically SIVmac239-infected rhesus macaque eliciting Gag<sub>206-216</sub>-specific CTL responses.</p> <p>Conclusions</p> <p>These results present in vitro and in vivo evidence implicating the interaction between Gag residues 205 in CA NTD and 340 in CA CTD in SIV replication. Thus, this study indicates a structural constraint for functional interaction between SIV CA NTD and CTD, providing insight into immunogen design to limit viral escape options.</p
Animal-borne video systems provide insight into the reproductive behavior of the Asian black bear
Previous studies on the mating system of the Asian black bear (Ursus thibetanus) have been limited to observations of captive populations and estimations of multiple paternities. Hence, the mating system of wild bears remains poorly understood. Animal-borne camera systems (i.e., cameras mounted on animals) provide novel tools to study the behavior of elusive animals. Here, we used an animal-borne video system to record the activities of wild bears during the mating season. Video camera collars were attached to four adult Asian black bears (male “A” and “B,” and female “A” and “B”) captured in Tokyo, central Japan, in May and June 2018. The collars were retrieved in July 2018, after which the video data were downloaded and analyzed in terms of bear activity and mating behavior. All the bears were found to interact with other uniquely identifiable bears for some of the time (range 9–22 days) during the deployment period (range 36–45 days), and multiple mating in males was documented. Both males and females exhibited different behaviors on social days (i.e., days when the bear interacted with conspecifics) compared with solitary days (i.e., days with no observed interactions with conspecifics). Compared with solitary days, the bears spent a lower proportion of time on foraging activities and higher proportion of time on resting activities on social days. Our results suggest that Asian black bears have a polygamous mating system, as both sexes consort and potentially mate with multiple partners during a given mating season. Furthermore, bears appeared to reduce their foraging activities on social days and engaged more in social interactions.publishedVersio
Animal-borne video systems provide insight into the reproductive behavior of the Asian black bear
Previous studies on the mating system of the Asian black bear (Ursus thibetanus) have been limited to observations of captive populations and estimations of multiple paternities. Hence, the mating system of wild bears remains poorly understood. Animal-borne camera systems (i.e., cameras mounted on animals) provide novel tools to study the behavior of elusive animals. Here, we used an animal-borne video system to record the activities of wild bears during the mating season. Video camera collars were attached to four adult Asian black bears (male “A” and “B,” and female “A” and “B”) captured in Tokyo, central Japan, in May and June 2018. The collars were retrieved in July 2018, after which the video data were downloaded and analyzed in terms of bear activity and mating behavior. All the bears were found to interact with other uniquely identifiable bears for some of the time (range 9–22 days) during the deployment period (range 36–45 days), and multiple mating in males was documented. Both males and females exhibited different behaviors on social days (i.e., days when the bear interacted with conspecifics) compared with solitary days (i.e., days with no observed interactions with conspecifics). Compared with solitary days, the bears spent a lower proportion of time on foraging activities and higher proportion of time on resting activities on social days. Our results suggest that Asian black bears have a polygamous mating system, as both sexes consort and potentially mate with multiple partners during a given mating season. Furthermore, bears appeared to reduce their foraging activities on social days and engaged more in social interactions.publishedVersio
Detection of SS-A/Ro and SS-B/La Autoantibodies Using Immunoblotting Procedure and Characterization of the Antigens from 293 Cells and KB Cells
Specific and sensitive assay was performed to detect both antiSS-A/Ro and antiSS-B/La antibodies in sera of patients with collagen diseases including SLE, PSS, etc. The SS-A/Ro and SS-B/La antigens were prepared from human spleen (HSE) and cultured human cell line (KB cells), while rabbit thymus extract (RTE) was used as SS-B/La antigen marker. The antigens were partially purified by DEAE cellulose column chromatography. The SS-A/Ro antibody was shown to react mainly with 58KDa peptide by means of immunoblotting. Sera containing both the SS-A/Ro and SS-B/La antibody reacted with 40KDa peptide of RTE, and 58KDa, 42KDa and 40KDa peptides of HSE. We found that some of SS-A/Ro antisera could further react with 64KDa peptide in HSE. The 58KDa peptide is rich in a cytoplasmic fraction of KB cells, and the 40KDa peptide in the nucleoplasmic fraction. KB cells are not less good source of the antigens than human spleen. Extracts of 293 cells (human embryonic kidney cells expressing adenovirus-5 El gene) were prepared by the same method from KB cells, though immunoblotting patterns of both SS-A/Ro and SS-B/La antigens of 293 cell extracts are similar to those of KB cells, the relative content of SS-B/La antigens in 293 cell extracts are decreased
Direct interaction of insulin-like growth factor-1 receptor with leukemia-associated RhoGEF
Insulin-like growth factor (IGF)-1 plays crucial roles in growth control and rearrangements of the cytoskeleton. IGF-1 binds to the IGF-1 receptor and thereby induces the autophosphorylation of this receptor at its tyrosine residues. The phosphorylation of the IGF-1 receptor is thought to initiate a cascade of events. Although various signaling molecules have been identified, they appear to interact with the tyrosine-phosphorylated IGF-1 receptor. Here, we identified leukemia-associated Rho guanine nucleotide exchange factor (GEF) (LARG), which contains the PSD-95/Dlg/ZO-1 (PDZ), regulator of G protein signaling (RGS), Dbl homology, and pleckstrin homology domains, as a nonphosphorylated IGF-1 receptor-interacting molecule. LARG formed a complex with the IGF-1 receptor in vivo, and the PDZ domain of LARG interacted directly with the COOH-terminal domain of IGF-1 receptor in vitro. LARG had an exchange activity for Rho in vitro and induced the formation of stress fibers in NIH 3T3 fibroblasts. When MDCKII epithelial cells were treated with IGF-1, Rho and its effector Rho-associated kinase (Rho-kinase) were activated and actin stress fibers were enhanced. Furthermore, the IGF-1–induced Rho-kinase activation and the enhancement of stress fibers were inhibited by ectopic expression of the PDZ and RGS domains of LARG. Taken together, these results indicate that IGF-1 activates the Rho/Rho-kinase pathway via a LARG/IGF-1 receptor complex and thereby regulates cytoskeletal rearrangements
Glutamate Snsor Using L-Glutamate Oxidase and Its Application for Sensing GOT/GPT Activity
L-Glutamate measurement and GOT/GPT assay was successful by H2O2 measurement using the L-glutamate oxidase with 4-aminoantipyrine / phenol method. But, in examination of oxigen electrode, immobilized L-glutamate oxidase at the cellulose to L-glutamate and GOT-GPT sensor, Lpglutamate measurement was used for the amperometric determination with non-fixed enzyme. On examination of electron mediator, response for L-glutamate was observed with each of the compounds ferricyane, ferrocene-COOH, ferrocene-MeOH, and benzoquinone. L-Glutamate was measured by carbon printed tip electrode the L-glutamate oxidase and ferricyane based on the principle of chronoamperometry. A linear calibration graph was obtained between 1mM and 30mM. These results suggest that L-glutamate oxidase is able to utilize to L-glutamate sensor, and that there is a strong possibility to put this sensor to sensing for GOT/GPT activity
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