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1.
Human and nonhuman primates comprehend the actions of other individuals by detecting social cues, including others’ goal-directed motor actions and faces. However, little is known about how this information is integrated with action understanding. Here, we present the ontogenetic and evolutionary foundations of this capacity by comparing face-scanning patterns of chimpanzees and humans as they viewed goal-directed human actions within contexts that differ in whether or not the predicted goal is achieved. Human adults and children attend to the actor’s face during action sequences, and this tendency is particularly pronounced in adults when observing that the predicted goal is not achieved. Chimpanzees rarely attend to the actor’s face during the goal-directed action, regardless of whether the predicted action goal is achieved or not. These results suggest that in humans, but not chimpanzees, attention to actor’s faces conveying referential information toward the target object indicates the process of observers making inferences about the intentionality of an action. Furthermore, this remarkable predisposition to observe others’ actions by integrating the prediction of action goals and the actor’s intention is developmentally acquired.  相似文献   
2.
The blood clamBarbatia virescens has a heterodimeric hemoglobin in erythrocytes. Interestingly, the congeneric clamsB. reeveana andB. lima contain quite different hemoglobins: tetramer and polymeric hemoglobin consisting of unusual didomain chain. The complete amino acid sequence of chain I ofB. virescens has been determined. The sequence was mainly determined from CNBr peptides and their subpeptides, and the alignment of the peptides was confirmed by sequencing of PCR-amplified cDNA forB. virescens chain I. The cDNA-derived amino acid sequence matched completely with the sequence proposed from protein sequencing.B. virescens chain I is composed of 156 amino acid residues, and the molecular mass was calculated to be 18,387 D, including a heme group. The sequence ofB. virescens chain I showed 35–42% sequence identity with those of the related clamAnadara trapezia and the congeneric clamB. reeveana. An evolutionary tree forAnadara andBarbatia chains clearly indicates that all of the chains are evolved from one ancestral globin gene, and that the divergence of chains has occurred in each clam after the speciation. The evolutionary rate for clam hemoglobins was estimated to be about four times faster than that of vertebrate hemoglobin. We suggest that blood clam hemoglobin is a physiologically less important molecule when compared with vertebrate hemoglobins, and so it evolved rapidly and resulted in a remarkable diversity in quaternary and subunit structure within a relatively short period.  相似文献   
3.
Larvae of the rice stem borer utilize simple carbohydrates and protein in their food at rates as high as most other lepidopterous larvae. The larvae also utilize starch at an unexpectedly high rate, in view of early evidences that the starch-hydrolyzing enzyme of the larval digestive tract is very weak and that the nutritive value of starch in synthetic food is very low. The results indicate that starch contained in the rice stem may be significant in the nutrition of the larvae in the field.
Zusammenfassung Die Larven von Chilo suppressalis Walker verwerten einfache Kohlehydrate und Proteine ihrer Nahrung in ebenso hohem Ausmaße wie die meisten anderen phytophagen Lepidopteren-larven. Jedoch nutzen die Raupen auch Stärke in einem unerwartet hohen Maße aus; unerwartet in Anbetracht der früheren Befunde, wonach das stärkehydrolysierende Ferment des larvalen Verdauungskanals schwach und der Nährwert von Stärke bei synthetischer Ernährung sehr niedrig ist. Die Ergebnisse weisen darauf hin, daß die im Reisstengel enthaltene Stärke für die Ernährung der Larven bedeutsam sein kann.
  相似文献   
4.
Abstract

Novel β-D-ribofuranosides having a 5-substituted imidazo [4,5-d] [1,3]thiazine ring, including the S6-congener 3 of oxanosine 2, were synthesized for screening their anticancer and antiviral activities.  相似文献   
5.
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017.  相似文献   
6.
7.
The number of microorganisms in the hindgut of dugongs (Dugong dugon) were estimated and their in vitro volatile fatty acid (VFA) production and degradation of eelgrass measured. Scanning electron microscopy showed that some rod bacteria attached to the surface of plant tissue degraded and eroded the cell walls. Number of starch-, lactate-, cellobiose-, pectin-, xylan- and cellulose-utilizing bacteria, sulfate-reducing bacteria and methane-producing bacteria were estimated at 109 ~ 1010 colony forming units g?1. Microorganisms degraded the cellulose and noncellulolytic components of the eelgrass, and about 47.3% of dry matter was degraded after 36?h in vitro incubation. The total VFA concentration was 10.5?mmol?dL?1 at 36?h incubation, which included 55.7?mol% acetate, 18.0?mol% n-butyrate and 15.1?mol% propionate. The gas composition of in vitro fermentation was 68.4% carbon dioxide, 22.2% methane and 9.4% hydrogen.  相似文献   
8.
9.
Small cell lung cancer (SCLC) is an aggressive tumor and prognosis remains poor. Therefore, the development of more effective therapy is needed. We previously reported that high levels of an anti-c-kit antibody (12A8) accumulated in SCLC xenografts. In the present study, we evaluated the efficacy of two antibodies (12A8 and 67A2) for radioimmunotherapy (RIT) of an SCLC mouse model by labeling with the 90Y isotope.

Methods

111In- or 125I-labeled antibodies were evaluated in vitro by cell binding, competitive inhibition and cellular internalization assays in c-kit-expressing SY cells and in vivo by biodistribution in SY-bearing mice. Therapeutic efficacy of 90Y-labeled antibodies was evaluated in SY-bearing mice upto day 28 and histological analysis was conducted at day 7.

Results

[111In]12A8 and [111In]67A2 specifically bound to SY cells with high affinity (8.0 and 1.9 nM, respectively). 67A2 was internalized similar to 12A8. High levels of [111In]12A8 and [111In]67A2 accumulated in tumors, but not in major organs. [111In]67A2 uptake by the tumor was 1.7 times higher than for [111In]12A8. [90Y]12A8, but not [90Y]67A2, suppressed tumor growth in a dose-dependent manner. Tumors treated with 3.7 MBq of [90Y]12A8, and 1.85 and 3.7 MBq of [90Y]67A2 (absorbed doses were 21.0, 18.0 and 35.9 Gy, respectively) almost completely disappeared approximately 2 weeks after injection, and regrowth was not observed except for in one mouse treated with 1.85 MBq [90Y]67A2. The area of necrosis and fibrosis increased depending on the RIT effect. Apoptotic cell numbers increased with increased doses of [90Y]12A8, whereas no dose-dependent increase was observed following [90Y]67A2 treatment. Body weight was temporarily reduced but all mice tolerated the RIT experiments well.

Conclusion

Treatment with [90Y]12A8 and [90Y]67A2 achieved a complete therapeutic response when SY tumors received an absorbed dose greater than 18 Gy and thus are promising RIT agents for metastatic SCLC cells at distant sites.  相似文献   
10.
Oxidative stress is produced in adipose tissue of obese subjects and has been associated with obesity-related disorders. Recent studies have shown that omega-3 polyunsaturated fatty acid (ω3-PUFA) has beneficial effects in preventing atherosclerotic diseases and insulin resistance in adipose tissue. However, the role of ω3-PUFA on adipocytes has not been elucidated. In this study, 3T3-L1 adipocytes were treated with ω3-PUFA and its metabolites, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), or 4-hydroxy hexenal (4-HHE). ω3-PUFA and its metabolites dose-dependently increased mRNA and protein levels of the anti-oxidative enzyme, heme oxygenase-1 (HO-1); whereas no changes in the well-known anti-oxidant molecules, superoxide dismutase, catalase, and glutathione peroxidase, were observed. Knockdown of nuclear factor erythroid 2-related factor 2 (Nrf-2) significantly reduced EPA, DHA or 4-HHE-induced HO-1 mRNA and protein expression. Also, pretreatment with ω3-PUFA prevented H2O2-induced cytotoxicity in a HO-1 dependent manner. In conclusion, treatment with EPA and DHA induced HO-1 through the activation of Nrf-2 and prevented oxidative stress in 3T3-L1 adipocytes. This anti-oxidant defense may be of high therapeutic value for clinical conditions associated with systemic oxidative stress.  相似文献   
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