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1.
AMB Express ; 11(1): 170, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34910268

RESUMO

The phenomenon of membrane vesicle (MV) production is known to be common to all bacterial cells. Although MVs are expected to be employed in a variety of applications, improving MV productivity is essential for applications. Since the deletion of the degP gene, a periplasmic dual-function protease and chaperone, in Escherichia coli has successfully improved MV production capacity, we tried to enhance MV productivity in the thermophilic M. ruber H328 by deleting the degP gene. One gene (mrH_0331) was selected for degP gene from the H328 genome and we constructed the mutant strain ∆degP by deleting the degP gene of the H328 strain that was replaced with the htk gene showing thermophilic kanamaycin resistance by homologous recombination. The mutant strain ∆degP exhibited smooth growth but a lower level of turbidity at 60 °C although there was no difference in growth at 55 °C between the wild strain and the mutant strain. Finally, we have confirmed that incubation at 60 °C increases MV in the mutant strain ∆degP strain about fivefold by using two fluorescent dyes, DiI and FM4-64, which is followed by TEM analysis. The deletion of the degP gene presumably causes an increase in denatured proteins at 60 °C, leading to enhanced MV production. Meanwhile, the S-layer protein included in the outer membrane of the H328 strain increased in the MV fraction prepared from the mutant cells incubated at 60 °C. This indicates that this method is effective for MV production and that degP deletion enhances it in strain H328.

2.
Nagoya J Med Sci ; 83(4): 883-891, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34916731

RESUMO

A 76-year-old woman was admitted to the emergency room of Nagano Municipal Hospital with the complain of severe back pain. Chest and abdominal enhanced computed tomography scans showed bilateral adrenal infarction and minute pulmonary nodules, but she had no respiratory symptoms. After admission, a family member of the patient was found to have been in close contact with a coronavirus disease 2019 (COVID-19) patient. Thus, polymerase chain reaction and antigen tests of severe acute respiratory syndrome coronavirus 2 were conducted, and both tests returned positive. D-dimer levels were normal on admission but increased 2 days thereafter. Anticoagulation therapy and steroid replacement were started, and the patient improved over about two weeks. One month after the onset of adrenal infarction, a rapid adrenocorticotropic hormone loading test was conducted, which revealed that the primary adrenal insufficiency due to adrenal infarction might have been caused by the COVID-19 infection. This case was rare and suggestive of adrenal infarction with COVID-19, which usually presents at the severe stage. In patients with COVID-19, attention should be paid to the onset of thrombosis, even with mild respiratory infection. We also suggest that patients with thrombosis should be suspected of having COVID-19 even in the absence of respiratory infectious symptoms in a situation of COVID-19 epidemic.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , COVID-19/complicações , Infarto , Trombose/etiologia , Idoso , COVID-19/sangue , COVID-19/diagnóstico , Teste de Ácido Nucleico para COVID-19 , Feminino , Humanos , Infarto/etiologia , Infecções Respiratórias , SARS-CoV-2/isolamento & purificação
3.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34215696

RESUMO

Standard macroeconomic models assume that households are rational in the sense that they are perfect utility maximizers and explain economic dynamics in terms of shocks that drive the economy away from the steady state. Here we build on a standard macroeconomic model in which a single rational representative household makes a savings decision of how much to consume or invest. In our model, households are myopic boundedly rational heterogeneous agents embedded in a social network. From time to time each household updates its savings rate by copying the savings rate of its neighbor with the highest consumption. If the updating time is short, the economy is stuck in a poverty trap, but for longer updating times economic output approaches its optimal value, and we observe a critical transition to an economy with irregular endogenous oscillations in economic output, resembling a business cycle. In this regime households divide into two groups: poor households with low savings rates and rich households with high savings rates. Thus, inequality and economic dynamics both occur spontaneously as a consequence of imperfect household decision-making. Adding a few "rational" agents with a fixed savings rate equal to the long-term optimum allows us to match business cycle timescales. Our work here supports an alternative program of research that substitutes utility maximization for behaviorally grounded decision-making.

4.
J Cell Sci ; 134(6)2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33674447

RESUMO

After centrosome duplication, centrioles elongate before M phase. To identify genes required for this process and to understand the regulatory mechanism, we investigated the centrioles in Drosophila premeiotic spermatocytes expressing fluorescently tagged centriolar proteins. We demonstrated that an essential microtubule polymerisation factor, Orbit (the Drosophila CLASP orthologue, encoded by chb), accumulated at the distal end of centrioles and was required for the elongation. Conversely, a microtubule-severing factor, Klp10A, shortened the centrioles. Genetic analyses revealed that these two proteins functioned antagonistically to determine centriole length. Furthermore, Cp110 in the distal tip complex was closely associated with the factors involved in centriolar dynamics at the distal end. We observed loss of centriole integrity, including fragmentation of centrioles and earlier separation of the centriole pairs, in Cp110-null mutant cells either overexpressing Orbit or depleted of Klp10A Excess centriole elongation in the absence of the distal tip complex resulted in the loss of centriole integrity, leading to the formation of multipolar spindle microtubules emanating from centriole fragments, even when they were unpaired. Our findings contribute to understanding the mechanism of centriole integrity, disruption of which leads to chromosome instability in cancer cells.


Assuntos
Centríolos , Proteínas de Drosophila , Animais , Proteínas de Ciclo Celular/genética , Centríolos/genética , Drosophila/genética , Proteínas de Drosophila/genética , Masculino , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos , Espermatócitos
5.
Bioinspir Biomim ; 14(3): 036011, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30708361

RESUMO

We have been developing a human mimetic musculoskeletal humanoid called Kenshiro, whose design concept is to thoroughly pursue an unprecedented anatomical fidelity to the human musculoskeletal structure. We believe that research on human mimetic musculoskeletal humanoids advances our understanding of humans and expands the applications of humanoids-such as a human body simulator that can quantitatively analyze internal human motion data. This paper describes Kenshiro's musculoskeletal body characteristics, software system, and preliminary experiments explaining the concept of potential application.


Assuntos
Biomimética , Movimento (Física) , Sistema Musculoesquelético , Robótica , Software , Humanos
6.
Lang Speech ; 62(4): 751-778, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30514147

RESUMO

This study investigates how pitch accent type and additive particles affect the activation of contrastive alternatives. In Experiment 1, German listeners heard declarative utterances (e.g., The swimmer wanted to put on flippers) and saw four printed words displayed on screen: one that was a contrastive alternative to the subject noun (e.g., diver), one that was non-contrastively related (e.g., pool), the object (e.g., flippers), and an unrelated distractor. Experiment 1 manipulated pitch accent type, comparing a broad focus control condition to two narrow focus conditions: with a contrastive or non-contrastive accent on the subject noun (nuclear L+H* vs. H+L*, respectively, followed by deaccentuation). In Experiment 2, the utterances in the narrow focus conditions were preceded by the unstressed additive particle auch ("also"), which may trigger alternatives itself. It associated with the accented subject. Results showed that, compared to the control condition, participants directed more fixations to the contrastive alternative when the subject was realized with a contrastive accent (nuclear L+H*) than when it was realized with non-contrastive H+L*, while additive particles had no effect. Hence, accent type is the primary trigger for signaling the presence of alternatives (i.e., contrast). Implications for theories of information structure and the processing of additive particles are discussed.


Assuntos
Atenção , Percepção da Altura Sonora , Semântica , Percepção da Fala , Feminino , Humanos , Idioma , Masculino , Adulto Jovem
7.
Chembiochem ; 19(3): 207-211, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29197144

RESUMO

The protein disulfide isomerase (PDI) family, found in the endoplasmic reticulum (ER) of the eukaryotic cell, catalyzes the formation and cleavage of disulfide bonds and thereby helps in protein folding. A decrease in PDI activity under ER stress conditions leads to protein misfolding, which is responsible for the progression of various human diseases, such as Alzheimer's, Parkinson's, diabetes mellitus, and atherosclerosis. Here we report that water-soluble cyclic diselenides mimic the multifunctional activity of the PDI family by facilitating oxidative folding, disulfide formation/reduction, and repair of the scrambled disulfide bonds in misfolded proteins.


Assuntos
Compostos Organosselênicos/metabolismo , Oxirredutases/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Dobramento de Proteína , Biocatálise , Sobrevivência Celular , Dissulfetos/química , Dissulfetos/metabolismo , Retículo Endoplasmático/enzimologia , Células Eucarióticas/enzimologia , Células HEK293 , Humanos , Estrutura Molecular , Compostos Organosselênicos/química , Oxirredutases/química , Isomerases de Dissulfetos de Proteínas/química , Solubilidade , Água/química
8.
IEEE Trans Vis Comput Graph ; 24(1): 120-130, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28866559

RESUMO

Clustering is a core building block for data analysis, aiming to extract otherwise hidden structures and relations from raw datasets, such as particular groups that can be effectively related, compared, and interpreted. A plethora of visual-interactive cluster analysis techniques has been proposed to date, however, arriving at useful clusterings often requires several rounds of user interactions to fine-tune the data preprocessing and algorithms. We present a multi-stage Visual Analytics (VA) approach for iterative cluster refinement together with an implementation (SOMFlow) that uses Self-Organizing Maps (SOM) to analyze time series data. It supports exploration by offering the analyst a visual platform to analyze intermediate results, adapt the underlying computations, iteratively partition the data, and to reflect previous analytical activities. The history of previous decisions is explicitly visualized within a flow graph, allowing to compare earlier cluster refinements and to explore relations. We further leverage quality and interestingness measures to guide the analyst in the discovery of useful patterns, relations, and data partitions. We conducted two pair analytics experiments together with a subject matter expert in speech intonation research to demonstrate that the approach is effective for interactive data analysis, supporting enhanced understanding of clustering results as well as the interactive process itself.

9.
Lang Speech ; 61(3): 409-429, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29027494

RESUMO

The present study examines how vulnerable perception of second language prosody is to increased task demands. German learners of Japanese, German non-learners without exposure to Japanese, and Japanese native listeners were tested in their ability to discriminate consonant length contrasts (compared to vowel length contrasts that served as a control condition). Memory load was increased by a longer inter-stimulus interval (2500 ms compared to 300 ms) and the demand on attention control was enhanced through the addition of the acoustic complexity of the stimuli (i.e., through a task-irrelevant pitch fall that occurred simultaneously with a consonant length contrast). The results showed high discrimination abilities, in all groups, when task demands were lowest. With increased task demands, only non-native listeners' discrimination abilities decreased: non-learners were strongly affected by both increased memory load and higher demand on attention control, while learners were only affected by the latter. The task-irrelevant acoustic complexity of the stimuli had a stronger impact on performance than increased memory load did. The findings suggest that second language learners established novel phonological representations but that the ability to use them could only be applied in the absence of distracting acoustic information. The non-native listeners' reduced sensitivity under increased task demands explains why even advanced learners still face difficulties in daily listening situations with numerous distractions.


Assuntos
Atenção , Discriminação Psicológica , Memória , Multilinguismo , Discriminação da Altura Tonal , Acústica da Fala , Percepção da Fala , Qualidade da Voz , Estimulação Acústica , Adulto , Feminino , Humanos , Masculino , Tempo de Reação , Fatores de Tempo , Adulto Jovem
10.
Biochemistry ; 56(42): 5644-5653, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29022711

RESUMO

Selenoglutathione (GSeH) is a selenium analogue of naturally abundant glutathione (GSH). In this study, this water-soluble small tripeptide was synthesized in a high yield (up to 98%) as an oxidized diselenide form, i.e., GSeSeG (1), by liquid-phase peptide synthesis (LPPS). Obtained 1 was applied to the investigation of the glutathione peroxidase (GPx)-like catalytic cycle. The important intermediates, i.e., GSe- and GSeSG, besides GSeO2H were characterized by 77Se NMR spectroscopy. Thiol exchange of GSeSG with various thiols, such as cysteine and dithiothreitol, was found to promote the conversion to GSe- significantly. In addition, disproportionation of GSeSR to 1 and RSSR, which would be initiated by heterolytic cleavage of the Se-S bond and catalyzed by the generated selenolate, was observed. On the basis of these redox behaviors, it was proposed that the heterolytic cleavage of the Se-S bond can be facilitated by the interaction between the Se atom and an amino or aromatic group, which is present at the GPx active site. On the other hand, when a catalytic amount of 1 was reacted with scrambled 4S species of RNase A in the presence of NADPH and glutathione reductase, native protein was efficiently regenerated, suggesting a potential use of 1 to repair misfolded proteins through reduction of the non-native SS bonds.


Assuntos
Dissulfetos/química , Glutationa Peroxidase/química , Glutationa/análogos & derivados , Glutationa/química , Ribonuclease Pancreático/química , Selênio/química , Glutationa/síntese química , Oxirredução
11.
Sci Robot ; 2(13)2017 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-33157878

RESUMO

Many systems and mechanisms in the human body are not fully understood, such as the principles of muscle control, the sensory nervous system that connects the brain and the body, learning in the brain, and the human walking motion. To address this knowledge deficit, we propose a human mimetic humanoid with an unprecedented degree of anatomical fidelity to the human musculoskeletal structure. The fundamental concept underlying our design is to consider the human mechanism, which contrasts with the conventional engineering approach used in the design of existing humanoids. We believe that the proposed human mimetic humanoid can be used to provide new opportunities in science, for instance, to quantitatively analyze the internal data of a human body in movement. We describe the principles and development of human mimetic humanoids, Kenshiro and Kengoro, and compare their anatomical fidelity with humans in terms of body proportions, skeletal structures, muscle arrangement, and joint performance. To demonstrate the potential of human mimetic humanoids, Kenshiro and Kengoro performed several typical human motions.

12.
Neuroophthalmology ; 40(2): 90-92, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27928390

RESUMO

A 69-year-old man with prostatic cancer under palliative care developed isolated right-sided oculomotor nerve palsy with pupillary impairment and persistent ocular pain. Cranial magnetic resonance imaging demonstrated metastasis of prostatic cancer to the right-sided cavernous sinus and orbital apex. In the English language literature, there are only six reported cases of isolated oculomotor nerve palsy secondary to prostatic cancer. In all cases, although there was metastatic lesion in the vicinity of the cavernous sinus, ocular pain did not develop. In the current patient, because metastatic tumour might involve the right-sided oculomotor nerve as well as lacrimal nerve, ocular pain developed.

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