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71.
Preliminary experiments were carried out to investigate the feasibility of using an electroencephalogram and heart rates to evaluate the efficacy of finger acupressure on the key points of planta pedis (both soles). Continuous electroencephalograms were recorded from 19 electrodes based on the International 10-20 electrode placement system on 22 university students (21+/-2.3 years). Spectral power changes were obtained at each electrode site. The power of the alpha1 frequency range (8-10 Hz) increased slightly during acupressure although no statistical significance was observed, while heart rates decreased in all subjects (p<0.05). Cerebral cortex asymmetry in the spectral power changes was not clearly observed during the right and left sole acupressure. This preliminary study suggests that a classification of subjects is necessary in understanding brain wave data during acupressure on soles.  相似文献   
72.
Various insect species lay tiny, thin- and soft-shelled eggs in a connected “egg mass”. Especially in several lepidopteran species, the structure of such clustered eggs is covered with complicated scale-like secretion, which has so far prevented analysis of individual embryos. However, few studies on methods to disperse egg clusters of such insects and to compare different methods have been carried out. To overcome these problems, we developed methods to separate egg masses into individual eggs, using two Tortricidae pests, Homona magnanima Diakonoff and Adoxophyes honmai Yasuda (Lepidoptera: Tortricidae). The eggs were successfully separated from each other using potassium hydroxide and sodium hypochlorite. Although the separated eggs no longer continued their embryogenesis, fixation with heptane–paraformaldehyde, permeabilization with heptane–methanol, and staining with several dyes enabled easy observation of embryogenesis. This protocol is expected to be applicable to other insect taxa and will facilitate further morphological and genetic studies in insects that lay egg masses.  相似文献   
73.
Trematode parasites have complex life cycles and use a variety of host species across different trophic levels. Thus, they can be used as indicators of disturbance and recovery of coastal ecosystems. Estuaries on the Pacific coast of northeastern Japan were heavily affected by the 2011 Tohoku earthquake tsunami. To evaluate the effect of the tsunami on the trematode community, we examined trematodes in the mud snail, Batillaria attramentaria, at five study sites (three sites severely exposed to the tsunami and two sites sheltered from the tsunami) in Sendai Bay for 2 years prior to and 8 years after the tsunami. While the trematode prevalence decreased at all study sites, the species richness decreased only at the sites exposed to the tsunami. Although parasitism increased over the study period post-tsunami, the community had not fully recovered 8 years after the event. Trematode community structure has changed every year since the tsunami and has not stabilised. This could be explained by the alteration of first and second intermediate host communities. Our study suggests that it will take more time for the recovery of the trematode community and the associated coastal ecosystem in the Tohoku region.  相似文献   
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A subclone, designated CEM-ON, derived from an azaguanine-resistant human leukemic T cell line, CEM-AG(R), constitutively secretes a colony-stimulating factor (CSF) which stimulates the production of macrophages from murine bone marrow progenitor cells. This CSF has been purified from serum-free conditioned medium. Highly purified CEM-ON CSF with a specific activity of 4.7 X 10(7) units/mg protein was obtained. Amino-terminal sequence analysis showed that the first 27 amino acids were identical to the amino-terminal sequence of the M-CSF (CSF-1) based on the cDNAs for human M-CSF. On SDS-PAGE analysis, CEM-ON CSF had an apparent molecular weight of 33,000-43,000; following reduction with 2-mercaptoethanol, this migrated as a 20,000-24,000 subunit, suggesting a homodimer structure. These results show that a human T cell line, CEM-ON, secretes M-CSF into its medium.  相似文献   
76.
The coq7/clk-1 gene was isolated from the long-lived mutant of Caenorhabditis elegans and was suggested to play a regulatory role in biological rhythm and longevity. The mouse COQ7 is homologous to Saccharomyces cerevisiae COQ7/CAT5 that is required for the biosynthesis of coenzyme Q (ubiquinone), an essential messenger in mitochondrial respiration. In the present study, we characterized the expression and processing of mouse COQ7. We found that COQ7 is highly expressed in tissues with high energy demand such as heart, muscle, liver, and kidney in mice. Biochemical analysis revealed that COQ7 is targeted to mitochondria where it is processed to mature form. Transgenic expression of mouse coq7 completely rescued the slowed rhythmic behaviors of clk-1 such as defecation. In life-span analysis, transgenic expression reverted the extended life span of clk-1 to the comparable level with wild-type control. These data strongly suggested that coq7 plays a pivotal role in the regulation of biological rhythms and the determination of life span in mammalian species.  相似文献   
77.
Saccharomyces cerevisiae Nfs1p is mainly found in the mitochondrial matrix and has been shown to participate in iron-sulfur cluster assembly. We show here that Nfs1p contains a potential nuclear localization signal, RRRPR, in its mature part. When this sequence was mutated to RRGSR, the mutant protein could not restore cell growth under chromosomal NFS1-depleted conditions. However, this mutation did not affect the function of Nfs1p in biogenesis of mitochondrial iron-sulfur proteins. The growth defect of the mutant was complemented by simultaneous expression of the mature Nfs1p, which contains the intact nuclear localization signal but lacks its mitochondrial-targeting presequence. These results suggest that a fraction of Nfs1p is localized in the nucleus and is essential for cell viability.  相似文献   
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79.
Myristoylated alanine-rich C kinase substrate (MARCKS) is a widely distributed specific protein kinase C (PKC) substrate and has been implicated in membrane trafficking, cell motility, secretion, cell cycle, and transformation. We found that amyloid beta protein (A beta) (25-35) and A beta (1-40) phosphorylate MARCKS in primary cultured rat microglia. Treatment of microglia with A beta (25-35) at 10 nM or 12-O-tetradecanoylphorbol 13-acetate (1.6 nM) led to phosphorylation of MARCKS, an event inhibited by PKC inhibitors, staurosporine, calphostin C, and chelerythrine. The A beta (25-35)-induced phosphorylation of MARCKS was inhibited by pretreatment with the tyrosine kinase inhibitors genistein and herbimycin A, but not with pertussis toxin. PKC isoforms alpha, delta, and epsilon were identified in microglia by immunocytochemistry and western blots using isoform-specific antibodies. PKC-delta was tyrosine-phosphorylated by the treatment of microglia for 10 min with A beta (25-35) at 10 nM. Other PKC isoforms alpha and epsilon were tyrosine-phosphorylated by A beta (25-35), but only to a small extent. We propose that a tyrosine kinase-activated PKC pathway is involved in the A beta (25-35)-induced phosphorylation of MARCKS in rat microglia.  相似文献   
80.
The effect of remodeling of a glycoantigen such as the alpha-Gal epitope, Galalpha1,3Galbeta1,4GlcNAc-R, by the introduction of glycosyltransferase genes on natural killer (NK) cell-mediated direct cytotoxicity was investigated using human peripheral blood mononuclear cells (PBMC) or an NK-like cell line, YT cells, as an effector, and swine endothelial cells (SEC) as a target. Several SEC transfectants were established by transfection with the genes for beta1,4-N-acetylglucosaminyltransferase III, alpha2, 3-sialyltransferase and alpha1,2-fucosyltransferase. These transfections led to dramatic reductions in both direct and indirect NK cell-mediated cytotoxicity, by 72-94% in the case of PBMC and 27-72% in that of YT cells, in addition to an effective reduction in xenoantigenicity, which is substantially caused by the alpha-Gal epitope, to human natural antibodies. The NK cell-mediated direct cytotoxicity was remarkably blocked by an anti-alpha-Gal epitope monoclonal antibody or GSI lectin which preferentially binds to the epitope. Furthermore, treatment of the parental cells with alpha-galactosidase resulted in a significant reduction in cytotoxicity. These results suggest that the alpha-Gal epitope is involved not only in hyperacute rejection and acute vascular rejection, but also in NK cell-mediated direct cytotoxicity. Thus, the genetic remodeling of the alpha-Gal epitope and probably other glycoantigens as well can be expected to represent a new approach for overcoming not only indirect but also direct immunity to xenografts.  相似文献   
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