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1.
Environ Manage ; 73(4): 777-787, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38097676

RESUMO

Understanding the regeneration and succession of belowground communities, particularly in forests, is vital for maintaining ecosystem health. Despite its importance, there is limited knowledge regarding how fungal communities change over time during ecosystem development, especially under different forest restoration strategies. In this study, we focused on two restoration methods used in northern Japan: monoculture planting and natural regeneration. We examined the responses of the fungal community to monoculture plantations (active tree planting) and naturally regenerated (passive regeneration) forests over a 50-year chronosequence, using natural forests as a reference. Based on DNA metabarcoding, we assessed the richness of fungal Operational Taxonomic Units (OTUs) and their dissimilarity. Our findings revealed that soil fungal richness remained stable after natural regeneration but declined in monoculture plantations, from 354 to 247 OTUs. While the compositional dissimilarity of fungal assemblages between monoculture plantations and natural forests remained consistent regardless of the time since tree planting, it significantly decreased after natural regeneration, suggesting recovery to a state close to the reference level. Notably, the composition of key functional fungal groups-saprotrophic and ectomycorrhizal- has increasingly mirrored that of natural forests over time following passive natural regeneration. In summary, our study suggests that monoculture plantations may not be effective for long-term ecosystem function and service recovery because of their limited support for soil fungal diversity. These results underscore the importance of natural regeneration in forest restoration and management strategies.


Assuntos
Ecossistema , Micobioma , Solo , Florestas , Plantas/microbiologia , Árvores , Microbiologia do Solo
2.
J Oral Rehabil ; 49(10): 937-943, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35801370

RESUMO

BACKGROUND: Exercise therapy is occasionally considered as an initial treatment for temporomandibular disorders. However, pain can be exacerbated during exercise therapy. OBJECTIVE: To investigate the immediate curative effects of exercise therapy in patients with masticatory muscle myalgia. METHODS: Fifty-nine patients with masticatory muscle myalgia were included. Therapists performed exercise therapy (stretched the painful masseter and/or cervical muscles along the direction of muscle contraction) in 10 rounds of traction, each lasting 10 s. The patient's pain-free maximum mouth opening distance and degree of pain (VAS value) before and immediately after exercise therapy were compared using the Wilcoxon signed-rank test. The Mann-Whitney U test was used for the subgroup comparisons. RESULTS: Mouth opening increased from 41 (IQR 38-43) to 46 (IQR 43-48) mm and pain alleviation from 48 (IQR 31-56) to 21 (IQR 10-56) immediately following exercise therapy (p < .001 for both). None of the patients experienced pain exacerbation or reduction in mouth opening post-exercise. No difference in mouth opening distance changes according to sex, painful side, painful site and therapist were observed (p > .05 for all). Pain reduction was greater in patients with unilateral pain (26, IQR 12-39) than those with bilateral (13, IQR 5-25) (p = .019). There were no differences in the change in the degree of pain according to sex, painful site and therapist (p > .05 for all). CONCLUSION: Exercise therapy immediately enlarged the mouth opening distance and reduced myalgia; therefore, it could be helpful in managing masticatory muscle myalgia.


Assuntos
Mialgia , Transtornos da Articulação Temporomandibular , Terapia por Exercício , Humanos , Músculo Masseter , Músculos da Mastigação , Mialgia/terapia , Transtornos da Articulação Temporomandibular/terapia
3.
Development ; 144(18): 3303-3314, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28928282

RESUMO

Neuronal differentiation and cell-cycle exit are tightly coordinated, even in pathological situations. When pathological neurons re-enter the cell cycle and progress through the S phase, they undergo cell death instead of division. However, the mechanisms underlying mitotic resistance are mostly unknown. Here, we have found that acute inactivation of retinoblastoma (Rb) family proteins (Rb, p107 and p130) in mouse postmitotic neurons leads to cell death after S-phase progression. Checkpoint kinase 1 (Chk1) pathway activation during the S phase prevented the cell death, and allowed the division of cortical neurons that had undergone acute Rb family inactivation, oxygen-glucose deprivation (OGD) or in vivo hypoxia-ischemia. During neurogenesis, cortical neurons became protected from S-phase Chk1 pathway activation by the DNA methyltransferase Dnmt1, and underwent cell death after S-phase progression. Our results indicate that Chk1 pathway activation overrides mitotic safeguards and uncouples neuronal differentiation from mitotic resistance.


Assuntos
Divisão Celular , Quinase 1 do Ponto de Checagem/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Neurônios/citologia , Neurônios/enzimologia , Animais , Morte Celular , Hipóxia Celular , Sobrevivência Celular , DNA (Citosina-5-)-Metiltransferase 1 , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Glucose/deficiência , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Neurogênese , Oxigênio , Proteína do Retinoblastoma/metabolismo , Fase S , Transdução de Sinais , Acidente Vascular Cerebral/patologia
4.
Langmuir ; 35(23): 7459-7468, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30379076

RESUMO

Collective migration is the mechanobiological interplay within migrating cell clusters and against extracellular matrixes (ECMs) underneath, mediating various physiological and pathological processes. Therefore, it is crucial to develop a robust platform on which collective migration can be studied under standardized conditions to understand how cells migrate differently between normal and disease states. We herein demonstrated phtotoactivatable hydrogel interfaces as suitable candidates for such applications. The substrate was composed of a poly(acrylamide) (PAAm) hydrogel whose surface was sequentially functionalized with poly-d-lysine (PDL) and photocleavable poly(ethylene glycol) (PEG). On the surface of the gel substrates, cell clusters with any given geometries can be prepared by controlling the irradiation patterns (geometrical cue), and their collective migration can be induced by the subsequent irradiation of the surrounding regions. Moreover, the substrate mechanical properties can be controlled by changing the composition of the PAAm hydrogel (mechanical cue), and the chemical properties were controlled by changing the amount of immobilized PDL, thereby altering the adsorbed amount of ECM proteins (chemical cue). The photoactivatable gel substrates were characterized by fluorescence microscopy, ζ-potential measurements, and the protein adsorption test. Through the study of the interplay of chemical, mechanical, and geometrical cues in the regulation of collective characteristics, we found additive effects of chemical and mechanical cues on the suppression of circular expansion by up-regulating the epithelial morphology. Also, the impact of geometrical cues became more significant by decreasing the chemical cue. We believe the present platform will be a useful research tool for the comprehensive mechanobiological analysis of collective cell migration.


Assuntos
Movimento Celular/efeitos dos fármacos , Hidrogéis/farmacologia , Luz , Fenômenos Mecânicos/efeitos dos fármacos , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Cães , Células Epiteliais/citologia , Células Madin Darby de Rim Canino , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia
5.
Development ; 140(11): 2310-20, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23615279

RESUMO

Cell cycle dysregulation leads to abnormal proliferation and cell death in a context-specific manner. Cell cycle progression driven via the Rb pathway forces neurons to undergo S-phase, resulting in cell death associated with the progression of neuronal degeneration. Nevertheless, some Rb- and Rb family (Rb, p107 and p130)-deficient differentiating neurons can proliferate and form tumors. Here, we found in mouse that differentiating cerebral cortical excitatory neurons underwent S-phase progression but not cell division after acute Rb family inactivation in differentiating neurons. However, the differentiating neurons underwent cell division and proliferated when Rb family members were inactivated in cortical progenitors. Differentiating neurons generated from Rb(-/-); p107(-/-); p130(-/-) (Rb-TKO) progenitors, but not acutely inactivated Rb-TKO differentiating neurons, activated the DNA double-strand break (DSB) repair pathway without increasing trimethylation at lysine 20 of histone H4 (H4K20), which has a role in protection against DNA damage. The activation of the DSB repair pathway was essential for the cell division of Rb-TKO differentiating neurons. These results suggest that newly born cortical neurons from progenitors become epigenetically protected from DNA damage and cell division in an Rb family-dependent manner.


Assuntos
Córtex Cerebral/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Proteína do Retinoblastoma/metabolismo , Animais , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Córtex Cerebral/embriologia , Dano ao DNA , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Camundongos , Camundongos Knockout , Reparo de DNA por Recombinação , Proteína do Retinoblastoma/genética , Proteína p107 Retinoblastoma-Like/genética , Proteína p107 Retinoblastoma-Like/metabolismo , Proteína p130 Retinoblastoma-Like/genética , Proteína p130 Retinoblastoma-Like/metabolismo
6.
Sci Rep ; 14(1): 2842, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310149

RESUMO

Ectomycorrhizal (ECM) fungi are functionally important in biogeochemical cycles in tropical ecosystems. Extracellular enzymatic activity of ECM on a ground-area basis is the product of two attributes; exploration capacity (ECM surface-area) and specific enzymatic activity. Here, we elucidated which attribute better explained the ECM enzymatic activity in response to different levels of soil phosphorus (P) and Nitrogen (N) availability in five Bornean tropical rainforests. We determined the surface area of ECM root tips as well as the enzymatic activities per ECM surface area for carbon (C), N and P degrading enzymes in each site. We evaluated the relationship of ECM enzyme activities with the resource availabilities of C (Above-ground net primary production; ANPP), N, and P of ECM by a generalized linear mixed model. The ECM enzymatic activities on a ground-area basis were more significantly determined by specific enzymatic activity than by the exploration capacity. Specific enzymatic activities were generally negatively affected by C (ANPP) and soil P availability. ECM fungi enhance the specific enzyme activity rather than the exploration capacity to maintain the capacity of nutrient acquisition. The less dependence of ECM fungi on the exploration capacity in these forests may be related to the limitation of C supply from host trees. We highlighted the adaptive mechanisms of ECM fungi on nutrient acquisition in tropical ecosystems through the response of enzymatic activity to nutrient availability across the elements.


Assuntos
Ecossistema , Micorrizas , Floresta Úmida , Solo , Fósforo , Micorrizas/fisiologia , Árvores/fisiologia , Florestas , Nitrogênio , Microbiologia do Solo
7.
ACS Appl Mater Interfaces ; 16(8): 10427-10438, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38375854

RESUMO

Capture and real-time recording of precise body movements using strain sensors provide personal information for healthcare monitoring and management. To acquire this information, a sensor that conforms to curved irregular surfaces, including biological tissue, is desired to record complex body movements while acting like a second skin to avoid interference with the movements. In this study, we developed a thin-film-type capacitive strain sensor that is flexible and stretchable on the surface of a living body. We fabricated conductive polymeric ultrathin films ("nanosheets") comprising polystyrene-block-polybutadiene (SB) elastomers and single-walled carbon nanotubes (SWCNTs) (i.e., SWCNT-SB nanosheets) via gravure coating; the SWCNT-SB-coated nanosheets were used as the flexible electrode in a capacitive strain sensor. The dielectric (DE) layer was then prepared using the silicone elastomer Ecoflex 00-30 because its Young's modulus is comparable to that of the epidermis. The normalized capacitance changes (ΔC/C0) in the sensor increased with increasing tensile strain over a range from 0-100%, indicating that the proposed sensor can measure the strain of biological movements, including those of skin and blood vessels. To improve sensor conformability further, the effect of sensor thickness on the gauge factor (GF) was investigated using thinner DE layers by focusing on their flexural rigidity. As a result, the GF increased from 0.64 to 1.13 as the DE layer thickness decreased from 260 to 40 µm. Finally, we evaluated the fabricated sensor's signal stability and mechanical durability, including during wireless sensing when applied to human skin and a vascular model. The ΔC/C0 values varied in response to the bending motion of a finger, dilation of a blood vessel, and the swallowing movement of the throat. These results indicate that our capacitive strain sensor is conformable and functional on biological tissue to enable monitoring of dynamic biological movements (e.g., pulse rate and arterial dilation) without wearer discomfort.


Assuntos
Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Humanos , Nanotubos de Carbono/química , Módulo de Elasticidade , Movimento , Movimento (Física)
8.
Front Robot AI ; 9: 933001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36325507

RESUMO

Social robots have grown increasingly integrated into our daily lives in recent years. Robots can be good social agents who engage with people, such as assistants and counselors, and good partners and companions with whom people can form good relationships. Furthermore, unlike devices such as smart speakers or virtual agents on a screen, robots have physicality, which allows them to observe the actual environment using sensors and respond behaviorally with full-body motions. In order to engage people in dialogue and create good relationships with robots as close partners, real-time interaction is important. In this article, we present a dialogue system platform developed with the aim of providing robots with social skills. We also built a system architecture for the robot to respond with speech and gestures within the dialogue system platform, which attempts to enable natural engagement with the robot and takes advantage of its physicality. In addition, we think the process called "co-creation" is important to build a good human-robot interaction system. Engineers must bridge the gap between users and robots in order for them to interact more effectively and naturally, not only by building systems unilaterally but also from a range of views based on the opinions of real users. We reported two experiments using the developed dialogue interaction system with a robot. One is an experiment with elderly people as the initial phase in this co-creation process. The second experiment was conducted with a wide range of ages, from children to adults. Through these experiments, we can obtain a lot of useful insights for improving the system. We think that repeating this co-creation process is a useful approach toward our goal that humans and robots can communicate in a natural way as good partners such as family and friends.

9.
Front Neurorobot ; 16: 890695, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677831

RESUMO

Dynamic manipulation of flexible objects such as fabric, which is difficult to modelize, is one of the major challenges in robotics. With the development of deep learning, we are beginning to see results in simulations and some actual robots, but there are still many problems that have not yet been tackled. Humans can move their arms at high speed using their flexible bodies skillfully, and even when the material to be manipulated changes, they can manipulate the material after moving it several times and understanding its characteristics. Therefore, in this research, we focus on the following two points: (1) body control using a variable stiffness mechanism for more dynamic manipulation, and (2) response to changes in the material of the manipulated object using parametric bias. By incorporating these two approaches into a deep predictive model, we show through simulation and actual robot experiments that Musashi-W, a musculoskeletal humanoid with a variable stiffness mechanism, can dynamically manipulate cloth while detecting changes in the physical properties of the manipulated object.

10.
Science ; 377(6613): 1440-1444, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36137034

RESUMO

Deadwood is a large global carbon store with its store size partially determined by biotic decay. Microbial wood decay rates are known to respond to changing temperature and precipitation. Termites are also important decomposers in the tropics but are less well studied. An understanding of their climate sensitivities is needed to estimate climate change effects on wood carbon pools. Using data from 133 sites spanning six continents, we found that termite wood discovery and consumption were highly sensitive to temperature (with decay increasing >6.8 times per 10°C increase in temperature)-even more so than microbes. Termite decay effects were greatest in tropical seasonal forests, tropical savannas, and subtropical deserts. With tropicalization (i.e., warming shifts to tropical climates), termite wood decay will likely increase as termites access more of Earth's surface.


Assuntos
Florestas , Aquecimento Global , Isópteros , Madeira , Animais , Ciclo do Carbono , Temperatura , Clima Tropical , Madeira/microbiologia
11.
Nat Commun ; 11(1): 4547, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917880

RESUMO

Biodiversity loss can alter ecosystem functioning; however, it remains unclear how it alters decomposition-a critical component of biogeochemical cycles in the biosphere. Here, we provide a global-scale meta-analysis to quantify how changes in the diversity of organic matter derived from plants (i.e. litter) affect rates of decomposition. We find that the after-life effects of diversity were significant, and of substantial magnitude, in forests, grasslands, and wetlands. Changes in plant diversity could alter decomposition rates by as much as climate change is projected to alter them. Specifically, diversifying plant litter from mono- to mixed-species increases decomposition rate by 34.7% in forests worldwide, which is comparable in magnitude to the 13.6-26.4% increase in decomposition rates that is projected to occur over the next 50 years in response to climate warming. Thus, biodiversity changes cannot be solely viewed as a response to human influence, such as climate change, but could also be a non-negligible driver of future changes in biogeochemical cycles and climate feedbacks on Earth.


Assuntos
Biodiversidade , Aquecimento Global , Compostos Orgânicos/química , Plantas/química , Biodegradação Ambiental , Biomassa , Florestas , Pradaria , Áreas Alagadas
12.
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
13.
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.

14.
Adv Healthc Mater ; 6(11)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28488337

RESUMO

Ischemic brain stroke is caused by blood flow interruption, leading to focal ischemia, neuron death, and motor, sensory, and/or cognitive dysfunctions. Angiogenesis, neovascularization from existing blood vessel, is essential for tissue growth and repair. Proangiogenic therapy for stroke is promising for preventing excess neuron death and improving functional recovery. Vascular endothelial growth factor (VEGF) is a critical factor for angiogenesis by promoting the proliferation, the survival, and the migration of endothelial cells. Here, angiogenic biomaterials to support injured brain regeneration are developed. Porous laminin (LN)-rich sponge (LN-sponge), on which histidine-tagged VEGF (VEGF-Histag) is immobilized via affinity interaction is developed. In an in vivo mouse stroke model, transplanting VEGF-Histag-LN-sponge produces remarkably stronger angiogenic activity than transplanting LN-sponge with soluble VEGF. The findings indicate that using affinity interactions to immobilize VEGF is a practical approach for developing angiogenic biomaterials for regenerating the injured brain.


Assuntos
Isquemia Encefálica , Proteínas Imobilizadas , Laminina , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Implantes de Medicamento/química , Implantes de Medicamento/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/farmacologia , Laminina/química , Laminina/farmacologia , Camundongos , Porosidade , Fator A de Crescimento do Endotélio Vascular/farmacologia
15.
Tissue Eng Part A ; 21(1-2): 193-201, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25010638

RESUMO

After brain injury, neuroblasts generated from endogenous neural stem cells migrate toward the injured site using blood vessels as a scaffold, raising the possibility of reconstructing blood vessel network scaffolds as a strategy for promoting endogenous neuronal regeneration. In this study, we designed biomaterials based on the components and morphology of blood vessel scaffolds, and examined their ability to guide the migration of neuroblasts into a brain lesion site in mice. Transplanted porous sponge containing components of the basement membrane (BM) matrix enhanced neuroblast migration into the lesion, and detailed morphological examination suggested that the infiltrating cells used the BM sponge as a migration scaffold. Laminin (LN)-rich porous sponge also enhanced the migration of neuroblasts into the lesion, whereas BM gel and gelatin porous sponge did not. We conclude that the transplantation of LN-rich porous sponge promotes neuroblast migration into cortical lesions. This study highlights the possibility of using artificial blood vessel scaffolds to promote the regeneration of injured cerebral cortex.


Assuntos
Movimento Celular/efeitos dos fármacos , Córtex Cerebral/patologia , Laminina/farmacologia , Neurônios/citologia , Alicerces Teciduais/química , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Membrana Basal/química , Camundongos Endogâmicos ICR , Microglia/citologia , Microglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Poríferos , Porosidade
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