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1.
Front Psychol ; 15: 1361588, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638518

RESUMO

Humanness perception, which attributes fundamental and unique human characteristics to other objects or people, has significant consequences for people's interactions. Notably, the failure to perceive humanness in older adults can lead to prejudice. This study investigates the effect of a target's age on humanness perception in terms of two dimensions: agency (the ability to act and do) and experience (the ability to feel and sense). We also examined brain activity using a magnetic resonance imaging (MRI) scanner in order to understand the underlying neural mechanisms. Healthy university students viewed the facial images of older and younger individuals and judged the humanness of each individual in terms of agency and experience while inside the MRI scanner. The results indicated that older adults were rated higher on experience, and no difference was found in ratings for agency between younger and older face images. Analysis of brain imaging data indicated that positive functional connectivity between the ventral and dorsal regions of the medial prefrontal cortex (mPFC) was greater when judging the humanness of younger faces than older faces. We also found that the negative functional connectivity between the left inferior frontal gyrus and postcentral gyrus was greater when judging the humanness of older faces as compared to that of younger faces. Although the current study did not show distinct brain activities related to humanness perception, it suggests the possibility that different brain connectivities are related to humanness perception regarding targets belonging to different age groups.

2.
Front Psychiatry ; 15: 1337776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510808

RESUMO

Introduction: Body-image disturbance is a major factor in the development of eating disorders, especially among young women. There are two main components: perceptual disturbance, characterized by a discrepancy between perceived and actual body size, and affective disturbance, characterized by a discrepancy between perceived and ideal body size. Interventions targeting body-image disturbance ask individuals to describe their own body without using negative expressions when either viewing it in a mirror or imagining it. Despite the importance of reducing body-image disturbance, its neural mechanisms remain unclear. Here we investigated the changes in neural responses before and after an intervention. We hypothesized that neural responses correlated with the degree of body-image disturbance would also be related to its reduction, i.e., a reduction in perceptual and affective disturbances would be related to changes in attentional and socio-cognitive processing, respectively. Methods: Twenty-eight young adult women without known psychiatric disorders underwent a single 40-min intervention. Participants completed tasks before and after the intervention, in which they estimated their perceived and ideal body sizes using distorted silhouette images to measure body-image disturbance. We analyzed the behavioral and neural responses of participants during the tasks. Results: The intervention did not significantly reduce body-image disturbance. Analysis of individual differences showed distinct changes in neural responses for each type of disturbance. A decrease in perceptual disturbance was associated with bodily visuospatial processing: increased activation in the left superior parietal lobule, bilateral occipital gyri, and right cuneus. Reduced affective disturbance was associated with socio-cognitive processing; decreased activation in the right temporoparietal junction, and increased functional connectivity between the left extrastriate body area and the right precuneus. Discussion: We identified distinct neural mechanisms (bodily visuospatial and socio-cognitive processing) associated with the reduction in each component of body-image disturbance. Our results imply that different neural mechanisms are related to reduced perceptual disturbance and the expression thereof, whereas similar neural mechanisms are related to the reduction and expression of affective disturbance. Considering the small sample size of this study, our results should be regarded as preliminary.

3.
Front Psychol ; 14: 1230192, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663345

RESUMO

The COVID-19 pandemic required people to adapt rapidly to the digital transformation of society for social survival, which highlighted the divide between those who can and cannot digitalize. Previous studies investigated factors promoting adaptation to digitalization; however, outcomes from adaptation to a digitalized society have not been sorted into a parsimonious model, even though there should be several multifaceted outcomes (e.g., usefulness, economic profit, and social outcome), each of which is promoted by different factors. If the effects of individual background factors can be revealed, including the technical-environment and survival-relevant personality in relation to each outcome, it would help in the creation of a society where more people play an active role by adapting to digitalization. This study aimed to construct such a model by identifying major outcomes gained in a digitalized society and investigating individual factors that contribute to the degree of gain of each of these outcomes. Five dimensions were identified by online surveys and factor analysis: Socialization (outcomes derived from new social connections created online), Space-time (freedom from time and space constraints), Economics (monetary outcome by using digital services), and Information (ease and amount of acquisition of information) were the positive outcomes, whereas Loneliness (feelings of not being able to keep up with digitization) was identified as a negative outcome. We determined that technical-environmental factors (e.g., familiarity with digital techniques and the amount of money that can be used for digitalization) facilitated gain in four positive outcomes. Notably, leadership and conscientiousness facilitated the Socialization gain while etiquette suppressed it. These factors' effects would reflect the importance of a personality trait prioritizing construction and maintenance of social relationships. This study implies that material outcomes (i.e., Space-time, Economics, and Information) are promoted by technical-environmental support, whereas social outcomes may additionally require motivation and a positive attitude for purposeful social engagement.

4.
Front Psychiatry ; 14: 1200473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636823

RESUMO

Coronavirus disease 2019 dramatically changed people's behavior because of the need to adhere to infection prevention and to overcome general adversity resulting from the implementation of infection prevention measures. However, coping behavior has not been fully distinguished from risk perception, and a comprehensive picture of demographic, risk-perception, and psychobehavioral factors that influence the major coping-behavior factors remain to be elucidated. In this study, we recruited 2,885 Japanese participants. Major coping-behavior and risk-perception factors were identified via exploratory factor analysis of 50 candidate items. Then, we conducted a hierarchical multiple regression analysis to investigate factors associated with each coping-behavior factor. We identified four types of coping behavior [CB1 (mask-wearing), CB2 (information-seeking), CB3 (resistance to social stagnation), and CB4 (infection-prevention)] and three risk-perception factors [RP1 (shortages of daily necessities), RP2 (medical concerns), and RP3 (socioeconomic concerns)]. CB1 was positively associated with female sex and etiquette. CB2 was positively related to RP1 and RP3. CB3 was positively related to RP1 and leadership, and negatively associated with etiquette. CB4 was positively associated with female sex, etiquette, and active well-being. This parsimonious model may help to elucidate essential social dynamics and provide a theoretical framework for coping behavior during a pandemic.

5.
Sci Adv ; 9(33): eadi1744, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37595044

RESUMO

Microwave (MW)-driven catalytic systems are attracting attention not only as an aggressive electrification strategy of the chemical industry but also as creating a unique catalytic reaction field that conventional equilibrium heating cannot achieve. This study unlocked direct and selective heating of single alkali metal cations in the pores of aluminosilicate zeolites under MW. Selectively heated Cs+ cations in FAU zeolite exhibited selective CH4 combustion performance, that is, COx generation at the heated Cs+ cations selectively occurred while side reactions in the low-temperature gas phase were suppressed. The Cs-O pair distribution function revealed by synchrotron-based in situ x-ray total scattering gave us direct evidence of peculiar displacement induced by MW, which was consistent with the results of molecular dynamics simulation mimicking MW heating. The concept of selective monoatomic heating by MW is expected to open a next stage in "microwave catalysis" science by providing physicochemical insights into "microwave effects."

6.
PLoS One ; 18(8): e0289651, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37590265

RESUMO

This paper proposes multidimensional scaling (MDS) applied to high-throughput chromosome conformation capture (Hi-C) data on genomic interactions to visualize DNA loops. Currently, the mechanisms underlying the regulation of gene expression are poorly understood, and where and when DNA loops are formed remains undetermined. Previous studies have focused on reproducing the entire three-dimensional structure of chromatin; however, identifying DNA loops using these data is time-consuming and difficult. MDS is an unsupervised method for reconstructing the original coordinates from a distance matrix. Here, MDS was applied to high-throughput chromosome conformation capture (Hi-C) data on genomic interactions to visualize DNA loops. Hi-C data were converted to distances by taking the inverse to reproduce loops via MDS, and the missing values were set to zero. Using the converted data, MDS was applied to the log-transformed genomic coordinate distances and this process successfully reproduced the DNA loops in the given structure. Consequently, the reconstructed DNA loops revealed significantly more DNA-transcription factor interactions involved in DNA loop formation than those obtained from previously applied methods. Furthermore, the reconstructed DNA loops were significantly consistent with chromatin immunoprecipitation followed by sequencing (ChIP-seq) peak positions. In conclusion, the proposed method is an improvement over previous methods for identifying DNA loops.


Assuntos
DNA , Análise de Escalonamento Multidimensional , DNA/genética , Cromatina/genética , Replicação do DNA , Genômica
7.
Atten Percept Psychophys ; 85(5): 1425-1436, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37337017

RESUMO

Several studies have investigated the relationship between working memory and attention. However, most of the relevant studies so far investigated top-down attention; only a few have examined possible interactions between bottom-up attention and visual working memory. In the present study, we focused on the visual saliency of different parts of pictures as an index of the degree to which one's bottom-up attention can be drawn towards each of them. We administered the Picture Span Test (PST) to investigate whether salient parts of pictures can influence the performance of visual working memory. The task required participants to judge the semantic congruency of objects in pictures and remember specific parts of pictures. In Experiment 1, we calculated a saliency map for the PST stimuli and found that salient but task-irrelevant parts of pictures could evoke intrusion errors. In Experiment 2, we demonstrated that longer gazing time at target areas results in a higher probability of making correct recognition. In addition, frequent gaze fixation and high normalized scan-path saliency values in task-irrelevant areas were associated with intrusion errors. These results suggest that visual information processed by bottom-up attention may affect working memory.


Assuntos
Movimentos Oculares , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Estimulação Luminosa/métodos , Cognição/fisiologia , Fixação Ocular , Percepção Visual/fisiologia
8.
Front Psychol ; 14: 1080376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998358

RESUMO

Recent psychological and neuroimaging studies on altruism-egoism dilemmas have promoted our understanding of the processes underlying altruistic motivation; however, little attention has been paid to the egoistic counter-dynamics that prompt hesitancy to help. These counter-dynamics may involve the construction of reasons not to help based on contextual elaboration and explain individual differences in the tendency to help others in daily life. In this functional magnetic resonance imaging (fMRI) study, we explored the neural correlates of altruism-egoism dilemmas during empathy-driven helping decisions, with particular attention to the counter-dynamics related to individual helping tendency traits. We used two context-rich helping decision scenarios. In the empathy dilemma (Emp) scenario, empathy-driven motivation to help a poor person was associated with a cost, whereas in the economic-dilemma (Eco) scenario, self-beneficial motivation to help a non-poor person was associated with a cost. Our results showed activation of the right anterior prefrontal cortices, supramarginal gyrus, and posterior cingulate cortex (PCC) for the altruism-egoism dilemma (i.e., Emp > Eco). A significant negative effect of the helping tendency trait score was observed on PCC activation; interestingly, this effect was observed for both Emp and Eco dilemmas. The identified neural correlates of altruism-egoism dilemmas appear to be related to the construction of decision reasons based on contextual elaboration in naturalistic situations. In contrast to the classical view, our results suggest a two-stage model that includes an altruistic helping decision followed by counter-dynamics to determine the individual helping tendency.

9.
Front Hum Neurosci ; 17: 985047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875234

RESUMO

Sincere praise reliably conveys positive or negative feedback, while flattery always conveys positive but unreliable feedback. These two praise types have not been compared in terms of communication effectiveness and individual preferences using neuroimaging. Through functional magnetic resonance imaging, we measured brain activity when healthy young participants received sincere praise or flattery after performing a visual search task. Higher activation was observed in the right nucleus accumbens during sincere praise than during flattery, and praise reliability correlated with posterior cingulate cortex activity, implying a rewarding effect of sincere praise. In line with this, sincere praise uniquely activated several cortical areas potentially involved in concern regarding others' evaluations. A high praise-seeking tendency was associated with lower activation of the inferior parietal sulcus during sincere praise compared to flattery after poor task performance, potentially reflecting suppression of negative feedback to maintain self-esteem. In summary, the neural dynamics of the rewarding and socio-emotional effects of praise differed.

10.
Front Public Health ; 10: 1022939, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36579065

RESUMO

Background: Studies on the survivors of the 2011 Great East Japan earthquake and tsunami have revealed eight factors, called power to live, which are closely related to resilience and effective coping after intense and prolonged stress. However, whether the eight factors, which were examined in adults, are applicable to children is unclear. The purpose of this study is to evaluate whether the eight-factor structure of power to live was present since late childhood. Method: A 34-item power to live questionnaire was filled by middle- to upper-grade elementary (n = 378) and junior high school students (n = 456). Moreover, because elementary school students may lack introspective ability, their power to live was evaluated through a parental assessment (n = 358). Additionally, we examined the relationship between each power to live factor and questions regarding disaster prevention awareness among 25 elementary school students. Results: The results from confirmatory factor analysis for factor structure revealed generally acceptable fit indices. The reports from elementary school students and their parents significantly positively correlated with each power to live factor. Although reliability indices for factors such as stubbornness, etiquette, self-transcendence, and active well-being were not good for elementary school students, the reliability indices for all factors, excluding stubbornness, increased in junior high school students. Moreover, we identified a correlation between problem-solving, altruism, and emotional regulation and questionnaire items regarding awareness of disaster prevention in elementary school students. Conclusion: Our results suggest that although factors common to adults, such as leadership, problem-solving, altruism, and emotional regulation, were identified at the elementary school stage, some factors, such as stubbornness, are in the process of being formed. Future studies should examine the developmental changes assumed to underlie these factors and their relationship to experience and neurodevelopmental basis.


Assuntos
Desastres , Terremotos , Adulto , Humanos , Criança , Reprodutibilidade dos Testes , Tsunamis , Adaptação Psicológica
11.
Chem Commun (Camb) ; 58(77): 10789-10792, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36093590

RESUMO

This report is the first describing a study quantitatively analysing aspects of oxide surface protonics in a dry H2 atmosphere. Elucidating surface protonics is important for electrochemical and catalytic applications. In this study, AC impedance spectroscopy was used to investigate surface conduction properties of porous CeO2 at low temperatures (423-573 K) and in a dry H2 atmosphere. Results demonstrated that the conductivity increased by several orders of magnitude when H2 was supplied. Dissociative adsorption of H2 contributes to conduction by forming proton-electron pairs. Also, H/D isotope exchange studies confirmed protons as the dominant conduction carriers. Furthermore, H2 adsorption equilibrium modelling based on the Langmuir mechanism was applied to explain the H2 partial pressure dependence of conductivity. For the first time, the obtained model explains the experimentally obtained results both qualitatively and quantitatively. These findings represent new insights into surface protonics in H2 atmosphere.

12.
Genes (Basel) ; 12(11)2021 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-34828279

RESUMO

The positions of enhancers and promoters on genomic DNA remain poorly understood. Chromosomes cannot be observed during the cell division cycle because the genome forms a chromatin structure and spreads within the nucleus. However, high-throughput chromosome conformation capture (Hi-C) measures the physical interactions of genomes. In previous studies, DNA extrusion loops were directly derived from Hi-C heat maps. Multidimensional Scaling (MDS) is used in this assessment to more precisely locate enhancers and promoters. MDS is a multivariate analysis method that reproduces the original coordinates from the distance matrix between elements. We used Hi-C data of cultured osteosarcoma cells and applied MDS as the distance matrix of the genome. In addition, we selected columns 2 and 3 of the orthogonal matrix U as the desired structure. Overall, the DNA loops from the reconstructed genome structure contained bioprocesses involved in transcription, such as the pre-transcriptional initiation complex and RNA polymerase II initiation complex, and transcription factors involved in cancer, such as Foxm1 and CREB3. Therefore, our results are consistent with the biological findings. Our method is suitable for identifying enhancers and promoters in the genome.


Assuntos
Neoplasias Ósseas/genética , Cromossomos Humanos/química , Elementos Facilitadores Genéticos , Osteossarcoma/genética , Regiões Promotoras Genéticas , Algoritmos , Bases de Dados Genéticas , Genômica/métodos , Humanos , Análise de Escalonamento Multidimensional , Conformação de Ácido Nucleico , Células Tumorais Cultivadas
13.
PLoS One ; 16(10): e0258325, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618878

RESUMO

Self-aid and mutual assistance among victims are critical for resolving difficulties in the immediate aftermath of a disaster, but individual facilitative factors for such resolution processes are poorly understood. To identify such individual factors in the background (i.e., disaster damage and demographic) and personality domains considering different types of difficulty and resolution, we analyzed survey data collected in the 3-year aftermath of the 2011 Great East Japan Earthquake and Tsunami. We first identified major types of difficulty using a cluster analysis of 18 difficulty domains and then explored individual factors that facilitated six types of resolution (self-help, request for help, help from family, help from an acquaintance, help through cooperation, and public assistance) of these difficulty types. We identified general life difficulties and medico-psychological difficulties as two broad types of difficulty; disaster damage contributed to both types, while some personality factors (e.g., neuroticism) exacerbated the latter. Disaster damage hampered self-resolution and forced a reliance on resolution through cooperation or public assistance. On the other hand, some demographic factors, such as being young and living in a three-generation household, facilitated resolution thorough the family. Several personality factors facilitated different types of resolution, primarily of general life difficulties; the problem-solving factor facilitated self-resolution, altruism, or stubbornness resolutions through requests, leadership resolution through acquaintance, and emotion-regulation resolution through public assistance. Our findings are the first to demonstrate the involvement of different individual, particularly personality, factors in survival in the complex social dynamics of this disaster stage. They may contribute to disaster risk mitigation, allowing sophisticated risk evaluation and community resilience building.


Assuntos
Autocuidado , Tsunamis , Adulto , Idoso , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Agric Food Chem ; 69(13): 3904-3911, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33761247

RESUMO

Genipin was reacted with benzylamine and several amino acids to prepare gardenia blue (GB). The time-course of GB formation with benzylamine was monitored by high-performance liquid chromatography (HPLC), liquid chromatography time-of-flight mass spectrometry (LC-TOFMS), and 1H and 13C NMR measurements. In this experiment, we determined the molecular structures of some intermediates using accurate masses and additional NMR techniques such as heteronuclear multiple bond correlation (HMBC). GBs with amino acids (GB-AAs) were characterized by both liquid and solid-state NMR measurements. Interestingly, many significant peaks appeared in the solid-state NMR spectra, although the 13C NMR spectra from solution samples did not show any distinct peaks. Therefore, we determined that GB-AAs had an alternating copolymer structure composed of methyne and 5H-2-pyrindine, which was substituted by amino acids at N atom and linked with methyne at 5 and 7 positions. To confirm this molecular structure, the pyrolysis gas chromatography-mass spectrometry (GC-MS) measurement of GB-AAs was carried out, and 5H-2-pyrindine and its methyl derivatives were formed as main pyrolysis products from the polymer chains.


Assuntos
Gardenia , Aminoácidos , Benzilaminas , Iridoides , Estrutura Molecular
15.
Neuroimage ; 210: 116577, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31978544

RESUMO

In laboratory settings, creativity is measured using tasks of divergent as well as convergent thinking. It has been suggested that brain connectivity is important for creativity. In the present study, we investigated the associations of convergent thinking performance of compound Remote Associates Test (CRAT) with fractional anisotropy (FA) in diffusion tensor imaging and regional white matter (WM) volume (rWMV) in voxel-based morphometry in a large sample of healthy young adults (360 males and 280 females; mean age: 20.9 years, SD â€‹= â€‹1.6). We showed that CRAT performance was positively correlated with WM pathway property (i.e., FA) in the left fronto-occipital fasciculus and the left inferior longitudinal fasciculus, which play important roles in processing of language and concept. Further, CRAT performance was negatively correlated with rWMV in the widespread frontal temporal subcortical and cerebellar WM areas, suggesting the unique association of convergent thinking with WM connectivity.


Assuntos
Imagem de Tensor de Difusão , Idioma , Rede Nervosa/anatomia & histologia , Pensamento/fisiologia , Substância Branca/anatomia & histologia , Adulto , Formação de Conceito/fisiologia , Criatividade , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Vias Neurais/anatomia & histologia , Vias Neurais/diagnóstico por imagem , Reconhecimento Visual de Modelos/fisiologia , Substância Branca/diagnóstico por imagem , Adulto Jovem
16.
Front Integr Neurosci ; 11: 37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29354036

RESUMO

Using a variety of tools is a common and essential component of modern human life. Patients with brain damage or neurological disorders frequently have cognitive deficits in their recognition and manipulation of tools. In this study, we focused on improving tool-related cognition using transcranial direct current stimulation (tDCS). Converging evidence from neuropsychology, neuroimaging and non- invasive brain stimulation has identified the anterior temporal lobe (ATL) and inferior parietal lobule (IPL) as brain regions supporting action semantics. We observed enhanced performance in tool cognition with anodal tDCS over ATL and IPL in two cognitive tasks that require rapid access to semantic knowledge about the function or manipulation of common tools. ATL stimulation improved access to both function and manipulation knowledge of tools. The effect of IPL stimulation showed a trend toward better manipulation judgments. Our findings support previous studies of tool semantics and provide a novel approach for manipulation of underlying circuits.

17.
Cogn Neuropsychol ; 33(3-4): 241-56, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27362967

RESUMO

The ability to recognize and use a variety of tools is an intriguing human cognitive function. Multiple neuroimaging studies have investigated neural activations with various types of tool-related tasks. In the present paper, we reviewed tool-related neural activations reported in 70 contrasts from 56 neuroimaging studies and performed a series of activation likelihood estimation (ALE) meta-analyses to identify tool-related cortical circuits dedicated either to general tool knowledge or to task-specific processes. The results indicate the following: (a) Common, task-general processing regions for tools are located in the left inferior parietal lobule (IPL) and ventral premotor cortex; and (b) task-specific regions are located in superior parietal lobule (SPL) and dorsal premotor area for imagining/executing actions with tools and in bilateral occipito-temporal cortex for recognizing/naming tools. The roles of these regions in task-general and task-specific activities are discussed with reference to evidence from neuropsychology, experimental psychology and other neuroimaging studies.


Assuntos
Mapeamento Encefálico/estatística & dados numéricos , Córtex Cerebral/fisiologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Atividade Motora/fisiologia , Rede Nervosa/fisiologia , Semântica , Humanos
18.
Parasitol Int ; 64(1): 26-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25220581

RESUMO

In 2009, a novel larval trematode of the family Gorgoderidae was found in the gonads of Nodularia douglasiae (Unionidae) from the lower reaches of the Yodo River, Osaka Prefecture, Japan. This is the first collection of trematodes in a unionid mussel in Japan. We investigated the morphology and life cycle of the trematode, and conducted a molecular phylogenetic analysis with other gorgoderid species, both those collected in the Yodo River water system and those reported in the literature. Immature adult worms were obtained from the ureters of the common carp Cyprinus carpio, the first known instance of a gorgoderid from these fish in Japan. Morphological characteristics and molecular data show that it belongs to the subfamily Gorgoderinae (genus Phyllodistomum sensu lato). Regarding the morphology, first intermediate host, and the infection site of adult worms, it resembles Phyllodistomum elongatum Nybelin, 1926 from Europe, but no comparable molecular data exist for Ph. elongatum. Three cytochrome c oxidase subunit I haplotypes were detected in the specimens analyzed, suggesting that the present species is indigenous to the Yodo River water system. The 28S ribosomal DNA data showed that this species is a member of the clade consisting of Ph. cf. symmetorchis, Ph. folium, Pseudophyllodistomum and Xystretrum. However, its phylogenetic position within the clade differs between the maximum likelihood and maximum parsimony trees, and the sister species of the present species remain unclear.


Assuntos
Trematódeos/classificação , Trematódeos/fisiologia , Unionidae/parasitologia , Animais , Bivalves/parasitologia , Carpas/parasitologia , DNA Ribossômico , Doenças dos Peixes/parasitologia , Japão , Larva/genética , Estágios do Ciclo de Vida , Filogenia , RNA Ribossômico 28S/genética , Rios , Trematódeos/genética , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária
19.
Zoolog Sci ; 31(3): 168-79, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24601779

RESUMO

We investigated the phylogeography of the Asian brackish water clam, Corbicula japonica, to clarify its demographic history using partial mitochondrial COII gene sequences (990 bp) from 283 individuals collected from around the Japanese archipelago and adjacent areas. Phylogenetic analyses revealed the presence of two major groups within our samples: monophyletic Group I comprising Lineages A-E of C. japonica and paraphyletic Group II consisting of Corbicula sp. Lineages A-C were distributed in Japan and Sakhalin Island, and Lineages D, E, and Corbicula sp. were distributed in the Korean Peninsula. Nested clade analysis (NCA) revealed that Lineage A-the dominant lineage in Japan-consisted of Pacific and Japan Sea lineages, the latter comprising southern and northern Japan Sea groups. Genetic diversity indices of the southern group were higher than those of the northern group, suggesting historical range expansion in the Sea of Japan from southwest to northeast. Geographical distribution of these genetic groups appears to have been influenced by major ocean currents around the Japanese archipelago. Dominant haplotypes in the star-shaped haplotype network of Lineage A were distributed throughout the entire distribution range of each genetic group, implying rapid range expansion of this species. The results of mismatch distribution analysis and molecular clock estimation suggest that expansion of lineage A occurred during the late Middle or Late Pleistocene. In contrast, restricted or past gene flow suggested by NCA and the many unique haplotypes (110/123; 89.4%) present in Lineage A suggest that gene flow among extant populations is rather limited.


Assuntos
Bivalves/genética , Bivalves/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/enzimologia , Animais , Demografia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Regulação Enzimológica da Expressão Gênica , Japão , Oceano Pacífico , Filogenia , Filogeografia
20.
PLoS One ; 8(1): e52372, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23341897

RESUMO

Expression patterns of the shell matrix protein genes MSI31 and MSI60 in the pearl sac epithelium were examined by in situ hybridization 38 days after implantation, and related to pearl quality. A pearl sac that produced a nacreous pearl showed very weak expression of MSI31 and strong expression of MSI60. A pearl sac, which yielded a prismatic pearl, strongly expressed MSI31 and very weakly expressed MSI60. In a complex pearl, whose surface consisted of a mosaic of both nacreous and prismatic layers, the expression pattern of MSI31 and MSI60 similarly corresponded to the underlying surface structures of the pearl. A nacreous pearl whose pearl sac showed strong MSI31 expression had an entirely nacreous surface composed of a laminar structure with unusual tablet growth at the corresponding site. MSI31 and MSI60 are the major components of the shell matrix proteins of the nacreous and prismatic layers. Clearly, high expression of MSI31 does not always result in prismatic secretion. These observations cannot be explained solely on the basis of the expression patterns of MSI31 and MSI60. We propose that, in addition to the MSI genes that form the prismatic and nacreous layers, upstream from these genes there are regulatory master genes that determine whether a nacreous layer (aragonite) or a prismatic layer (calcite) is formed.


Assuntos
Estruturas Animais/metabolismo , Epitélio/metabolismo , Regulação da Expressão Gênica , Hibridização In Situ , Nácar/metabolismo , Pinctada/metabolismo , Proteínas/genética , Estruturas Animais/ultraestrutura , Animais , Epitélio/ultraestrutura , Pigmentação , Pinctada/citologia , Pinctada/ultraestrutura , Proteínas/metabolismo
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