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81.
James S. Albert Michael J. Lannoo Tamaki Yuri 《Evolution; international journal of organic evolution》1998,52(6):1760-1780
In this paper, we propose a method to test alternative hypotheses of phenotypic evolution. The method compares patterns observed in phylogenetic character data with patterns expected by explicit models of evolutionary process. Observed patterns of character-state diversity are assessed from four properties of character-state change derived from a phylogenetic analysis: the sequence and correlation of transformations on a cladogram and the spatial and functional localization of these transformations to parts of an organism. Patterns expressed in terms of the localization of transformations are compared with the expectations of null models that the number of transformations is proportional to measures of size or complexity. Deviations from the values expected by the null models are then compared with qualitative expectations of the models. The method is applied to characters in the nervous system of gymnotiform electric fishes. Patterns in the diversity of 63 reconstructed character-state changes are compared with the expectations of 10 published models of neural evolution. A total of 63 expectations are reviewed, of which 33 (52%) are found to be consistent with the gymnotiform neural data. In general, the models reviewed are not successful at making global predictions, in part because they have been cast in excessively general terms. The data support the conclusion that evolution in the nervous system of gymnotiforms has involved a mosaic of processes, each operating differentially on functional and developmental systems and at different spatial and temporal scales. The results also indicate that more refined models are required, each making more explicit predictions. 相似文献
82.
The per capita home range area of Japanese macaques,Macaca fuscata, is significantly smaller in evergreen forest than in deciduous forest, though a corresponding difference in food resource
utilization patterns has never been described. The present study compared the home range utilization pattern of Japanese macaques
living in two habitats: the Yakushima population inhabits an evergreen forest, while the Kinkazan population inhabits a deciduous
forest. We found that in the Yakushima population, (1) food density was higher; (2) inter-feeding bout sites distance was
shorter; (3) daily travel distance was shorter; (4) home range size was smaller; and (5) the unit value of the main home range
was higher, than in the Kinkazan population. Yakushima groups utilized a small home range area intensively, compared to Kinkazan
groups. We also found that a Yakushima group shared 24% of its main home range with neighboring groups, though a Kinkazan
group shared only 10% with other groups. It is supposed that food distribution affects daily ranging pattern, and ultimately
the social relationships between groups in Japanese macaques. 相似文献
83.
Alternate activity in the synergistic muscles during prolonged low-level contractions 总被引:1,自引:0,他引:1
Tamaki H.; Kitada K.; Akamine T.; Murata F.; Sakou T.; Kurata H. 《Journal of applied physiology》1998,84(6):1943-1951
The purpose ofthis study was to investigate the functional interrelationship betweensynergistic muscle activities during low-level fatiguing contractions.Six human subjects performed static and dynamic contractions at anankle joint angle of 110° plantar flexion and within the range of90-110° (anatomic position = 90°) under constant load(10% maximal voluntary contraction) for 210 min. Surfaceelectromyogram records from lateral gastrocnemius (LG), medialgastrocnemius (MG), and soleus (Sol) muscles showed high and silentactivities alternately in the three muscles and a complementary andalternate activity between muscles in the time course. In the secondhalf of all exercise times, the number of changes in activity increasedsignificantly (P < 0.05) in each muscle. The ratios of active to silent periods of electromyogram activity were significantly higher (P < 0.05) in MG (4.5 ± 2.2) and Sol (4.3 ± 2.8) than in the LG(0.4 ± 0.1), but no significant differences were observed betweenMG and Sol. These results suggest that the relativeactivation of synergistic motor pools are not constant during alow-level fatiguing task. 相似文献
84.
Manami Miyai Shingo Eikawa Akihiro Hosoi Tamaki Iino Hirokazu Matsushita Midori Isobe Akiko Uenaka Heiichiro Udono Jun Nakajima Eiichi Nakayama Kazuhiro Kakimi 《PloS one》2015,10(8)
Comprehensive immunological evaluation is crucial for monitoring patients undergoing antigen-specific cancer immunotherapy. The identification and quantification of T cell responses is most important for the further development of such therapies. Using well-characterized clinical samples from a high responder patient (TK-f01) in an NY-ESO-1f peptide vaccine study, we performed high-throughput T cell receptor β-chain (TCRB) gene next generation sequencing (NGS) to monitor the frequency of NY-ESO-1-specific CD8+ T cells. We compared these results with those of conventional immunological assays, such as IFN-γ capture, tetramer binding and limiting dilution clonality assays. We sequenced human TCRB complementarity-determining region 3 (CDR3) rearrangements of two NY-ESO-1f-specific CD8+ T cell clones, 6-8L and 2F6, as well as PBMCs over the course of peptide vaccination. Clone 6-8L possessed the TCRB CDR3 gene TCRBV11-03*01 and BJ02-01*01 with amino acid sequence CASSLRGNEQFF, whereas 2F6 possessed TCRBV05-08*01 and BJ02-04*01 (CASSLVGTNIQYF). Using these two sequences as models, we evaluated the frequency of NY-ESO-1-specific CD8+ T cells in PBMCs ex vivo. The 6-8L CDR3 sequence was the second most frequent in PBMC and was present at high frequency (0.7133%) even prior to vaccination, and sustained over the course of vaccination. Despite a marked expansion of NY-ESO-1-specific CD8+ T cells detected from the first through 6th vaccination by tetramer staining and IFN-γ capture assays, as evaluated by CDR3 sequencing the frequency did not increase with increasing rounds of peptide vaccination. By clonal analysis using 12 day in vitro stimulation, the frequency of B*52:01-restricted NY-ESO-1f peptide-specific CD8+ T cells in PBMCs was estimated as only 0.0023%, far below the 0.7133% by NGS sequencing. Thus, assays requiring in vitro stimulation might be underestimating the frequency of clones with lower proliferation potential. High-throughput TCRB sequencing using NGS can potentially better estimate the actual frequency of antigen-specific T cells and thus provide more accurate patient monitoring. 相似文献
85.
Munetaka Ozeki Adeeb Salah Wulamujiang Aini Keiji Tamaki Hironori Haga Aya Miyagawa-Hayashino 《PloS one》2015,10(8)
The biological significance of STK17A, a serine/threonine kinase, in the liver is not known. We analyzed STK17A expression in HepG2 cells and human liver tissue. Accordingly, we investigated whether STK17A could help in identifying earlier changes during the evolution of chronic rejection (CR) after liver transplantation. RT-PCR and immunofluorescence were used to analyze STK17A expression in HepG2 cells. Antibody microarray was performed using human liver samples from CR and healthy donors. Immunohistochemistry was used to verify the clinical utility of STK17A on sequential biopsies for the subsequent development of CR. A novel short isoform of STK17A was found in HepG2 cells. STK17A was localized in the nuclei and bile canaliculi in HepG2 cells and human livers. Microarray of STK17A revealed its decrease in failed liver allografts by CR. During the evolution of CR, the staining pattern of bile canalicular STK17A gradually changed from diffuse linear to focal intermittent. The focal intermittent staining pattern was observed before the definite diagnosis of CR. In conclusion, the present study was the first to find localization of STK17A in normal bile canaliculi. Abnormal expression and localization of STK17A were associated with CR of liver allografts since the early stage of the rejection process. 相似文献
86.
Hirono Otomaru Taro Kamigaki Raita Tamaki Jamie Opinion Arlene Santo Edgard Daya Michiko Okamoto Mariko Saito Veronica Tallo Soccoro Lupisan Akira Suzuki Hitoshi Oshitani 《PloS one》2015,10(4)
This study aimed to determine the role of influenza-like illness (ILI) surveillance conducted on Leyte Island, the Philippines, including involvement of other respiratory viruses, from 2010 to 2013. ILI surveillance was conducted from January 2010 to March 2013 with 3 sentinel sites located in Tacloban city, Palo and Tanauan of Leyte Island. ILI was defined as fever ≥38°C or feverish feeling and either cough or running nose in a patient of any age. Influenza virus and other 5 respiratory viruses were searched. A total of 5,550 ILI cases visited the 3 sites and specimens were collected from 2,031 (36.6%) cases. Among the cases sampled, 1,637 (75.6%) were children aged <5 years. 874 (43.0%) cases were positive for at least one of the respiratory viruses tested. Influenza virus and respiratory syncytial virus (RSV) were predominantly detected (both were 25.7%) followed by human rhinovirus (HRV) (17.5%). The age distributions were significantly different between those who were positive for influenza, HRV, and RSV. ILI cases were reported throughout the year and influenza virus was co-detected with those viruses on approximately half of the weeks of study period (RSV in 60.5% and HRV 47.4%). In terms of clinical manifestations, only the rates of headache and sore throat were significantly higher in influenza positive cases than cases positive to other viruses. In conclusion, syndromic ILI surveillance in this area is difficult to detect the start of influenza epidemic without laboratory confirmation which requires huge resources. Age was an important factor that affected positive rates of influenza and other respiratory viruses. Involvement of older age children may be useful to detect influenza more effectively. 相似文献
87.
Mai Tsuchiya Yuka Nakajima Naoya Hirata Tamaki Morishita Hiroyuki Kishimoto Yasunari Kanda Keiji Kimura 《Biochemical and biophysical research communications》2014
Cancer stem cells (CSCs) have several distinctive characteristics, including high metastatic potential, tumor-initiating potential, and properties that resemble normal stem cells such as self-renewal, differentiation, and drug efflux. Because of these characteristics, CSC is regarded to be responsible for cancer progression and patient prognosis. In our previous study, we showed that a ubiquitin E3 ligase carboxyl terminus of Hsc70-interacting protein (CHIP) suppressed breast cancer malignancy. Moreover, a recent clinical study reported that CHIP expression levels were associated with favorable prognostic parameters of patients with breast cancer. Here we show that CHIP suppresses CSC properties in a population of breast cancer cells. CHIP depletion resulted in an increased proportion of CSCs among breast cancers when using several assays to assess CSC properties. From our results, we propose that inhibition of CSC properties may be one of the functions of CHIP as a suppressor of cancer progression. 相似文献
88.
Mahiko Abe Masahiro Kobayashi Motoya Tamaki Eiji Fujiyoshi Norio Kikuchi 《Journal of applied phycology》2010,22(4):405-408
To allow to discriminate rapidly the strains of Porphyra tenera var. tamatsuensis, cultivars of which grow more vigorously than strains of P. tenera var. tenera, strains of both varieties were examined by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP)
analysis using mitochondrial DNA related to the ATP synthase F0 subunit 6 (ATP6) gene. The lengths of all sequences in this
region of three strains of each variety were 670 bp and had just a single nucleotide substitution. Digestion with the restriction
enzyme of TaaI yielded three visible bands which appeared in the three strains of P. tenera var. tamatsuensis, whereas two bands appeared in the three strains of P. tenera var. tenera. We therefore conclude that PCR-RFLP analysis is a valuable tool for discrimination of P. tenera var. tamatsuensis among the stock of P. tenera strains used for mariculture. 相似文献
89.
Shinzato N Watanabe I Meng XY Sekiguchi Y Tamaki H Matsui T Kamagata Y 《Microbial ecology》2007,54(4):627-636
The anaerobic free-living ciliate, Trimyema compressum, is known to harbor both methanogenic archaeal and bacterial symbionts in the cytoplasm. To clarify their phylogenetic belongings,
a full-cycle rRNA approach was applied to this symbiosis. Phylogenetic analysis showed that the methanogenic symbiont was
related to Methanobrevibacter arboriphilicus, which was distantly related to symbionts found in other Trimyema species. This result suggested that Trimyema species do not require very specific methanogenic symbionts, and symbiont replacement could have occurred in the history
of Trimyema species. On the other hand, the bacterial symbiont was located near the lineage of the family Syntrophomonadaceae in the
phylum Firmicutes. The sequence similarity between the bacterial symbiont and the nearest species was 85%, indicating that
bacterial symbionts may be specific to the Trimyema species. The elimination of bacterial symbionts from the ciliate cell by antibiotic treatment resulted in considerably decreased
host growth. However, it was not restored by stigmasterol addition (<2 μg ml−1), which was different from the previous report that showed that the symbiont-free strain required exogenous sterols for growth.
In addition, the decline of host growth was not accompanied by host metabolism shift toward the formation of more reduced
products, which suggested that the contribution of bacterial symbionts to the host ciliate was not a dispose of excessive
reducing equivalent arising from the host’s fermentative metabolism as methanogenic symbionts do. This study showed that bacterial
symbionts make a significant contribution to the host ciliate by an unknown function and suggested that interactions between
bacterial symbionts and T. compressum are more complicated than hitherto proposed. 相似文献
90.
Iino M Nomura T Tamaki Y Yamada Y Yoneyama K Takeuchi Y Mori M Asami T Nakano T Yokota T 《Phytochemistry》2007,68(12):1664-1673
Progesterone is a mammalian gonadal hormone. In the current study, we identified and quantified progesterone in a range of higher plants by using GC-MS and examined its effects on the vegetative growth of plants. The growth of Arabidopsis (Arabidopsis thaliana) seedlings was promoted by progesterone at low concentrations but suppressed at higher concentrations under both light and dark growth conditions. The growth of the gibberellin-deficient mutant lh of pea (Pisum sativum) was also promoted by progesterone. An earlier study demonstrated that progesterone binds to MEMBRANE STEROID BINDING PROTEIN 1 (MSBP1) of Arabidopsis. In this work, we cloned the homologous genes of Arabidopsis, MSBP2 and STEROID BINDING PROTEIN (SBP), as well as of rice (Oryza sativa), OsMSBP1, OsMSBP2 and OsSBP and examined their expression in plant tissues. All of these genes, except OsMSBP1, were expressed abundantly in plant tissues. The roles of progesterone in plant growth were also discussed. 相似文献