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1.
Nano Lett ; 22(15): 6128-6134, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35852968

RESUMO

Energy consumption and post-treatment of chemical reagent residues are important issues that hinder the sustainable production of the natural building blocks of cellulose nanofibrils (CNFs). In this study, we realize a low-energy, zero-waste process for CNF production by designing a novel reactive deep eutectic solvent (DES), the residue of which can be directly used as a plant growth regulator. After pretreatment with the DES, cellulose fibers self-delaminate into thin layers referred to as pseudo-CNFs, as their strength, toughness and transmittance are comparable to those of CNFs. Pseudo-CNFs break into smaller particles during recycling and thus display unique mechanical upcycling. After facile fibrillation, the obtained CNFs can independently form freestanding sub-micrometer films that show a strong, full coloration, which is demonstrated for the first time. Our concept can enable a green process, and the developed cellulosic materials may find various applications as structural materials and optical coatings.


Assuntos
Nanofibras , Celulose/química , Nanofibras/química
2.
Odontology ; 110(3): 476-481, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35000009

RESUMO

This study investigated the effects of acute footshock stress (FS) on the occurrence of rhythmic masticatory muscle activity (RMMA) during sleep in guinea pigs. Animals were prepared for chronic recordings from electroencephalogram, electrooculogram and electromyograms of neck and masseter muscles. The signals were recorded for six hours on the two successive days: the first day with stress-free condition (non-FS condition) and the second day with acute FS (FS condition). Sleep/wake states and RMMA were scored visually. Sleep variables and the frequency of RMMA occurring during non-rapid eye movement (NREM) sleep were compared during 6-h periods between the two conditions. Compared to non-FS condition, the amount of total sleep and NREM sleep significantly reduced during 2 h following the acute FS in the FS condition. Similarly, the frequency of RMMA significantly increased during 2 h following the acute FS for the FS condition compared to non-FS condition. During 2-6 h after FS in the FS condition, sleep variables and the frequency of RMMA did not differ from those without FS in the non-FS condition. These results suggest that acute experimental stress can induce transient changes in sleep-wake states and the occurrence of RMMA in experimental animals.


Assuntos
Músculo Masseter , Bruxismo do Sono , Animais , Cobaias , Músculos da Mastigação/fisiologia , Polissonografia , Sono
3.
Radiat Environ Biophys ; 60(3): 411-419, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33959794

RESUMO

Radiation-induced fibrosis (RIF) is a serious complication that occurs after irradiation and which is caused by the deposition of extracellular matrix (ECM) proteins such as collagen. However, the underlying mechanisms, including the expression of the cytokines, that promote the RIF process, are not yet fully understood. MicroRNAs (miRNAs) have recently been suggested to act as post-transcriptional repressors for many genes; however, their role in the process of RIF remains to be elucidated. Our previous study showed that ionizing radiation increased the type I collagen expression through the activation of transforming growth factor (TGF)-ß, while miR-29 repressed this increase. This study aimed to investigate the mechanisms by which the expression of connective tissue growth factor (CTGF), a downstream mediator of TGF-ß, is controlled by miRNAs post-transcriptionally after exposure to ionizing radiation. The expression of CTGF in NIH-3T3 cells and mouse embryonic fibroblasts was increased by ionizing radiation. However, this increase was suppressed with a specific inhibitor of TGF-ß receptor. Among the predictable miRNAs that target the CTGF gene, the expression of miR-26a was downregulated after exposure to ionizing radiation and this regulation was negatively mediated by TGF-ß signaling. miR-26a negatively regulated the CTGF expression at the post-transcriptional level; however, ionizing radiation suppressed this negative regulation. In addition, the overexpression of miR-26a inhibited the expression of CTGF and type I collagen after irradiation. In conclusion, miR-26a modulates the expression of CTGF via TGF-ß signaling in irradiated fibroblasts. The results suggest the potential application of miR-26a in the treatment of RIF.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/efeitos da radiação , MicroRNAs , Radiação Ionizante , Animais , Fator de Crescimento do Tecido Conjuntivo/genética , Fibroblastos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
4.
Connect Tissue Res ; 59(3): 263-273, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28829698

RESUMO

AIMS: Col5a1 encodes the α1 chain of type V collagen, a quantitatively minor fibrillar collagen that is critical for the formation and function of the organs in the body. MicroRNAs (miRNAs) are small noncoding RNAs that posttranscriptionally regulate biological functions by binding to the 3'-untranslated region (3'UTR) of specific target mRNA. In this study, we investigated the posttranscriptional regulation of miRNAs on the Col5a1 gene expression. MATERIALS AND METHODS: We cultured osteoblasts and fibroblasts of cell lines. To examine the 3'UTR activity of the Col5a1 gene, chimeric plasmids constructs containing the core promoter and 3'UTR of Col5a1 were generated and luciferase assays were performed. We also evaluated the role of miRNA using constructs that were mutated at the putative binding sites of miRNA. In addition, we evaluated the endogenous mRNA and protein, and luciferase activity of the Col5a1 gene after miRNA overexpression/knockdown or CRISPR/Cas9-induced knockout. RESULTS: The luciferase assay showed a decreased activity of the 3'UTR of Col5a1 gene. However, the expression of the mutant constructs of miRNA-binding sites was restored. The overexpression of miRNA inhibited the Col5a1 gene not only with regard to the luciferase activity and endogenous mRNA but also at the protein level. In contrast, the RNAi-mediated knockdown or CRISPR/Cas9 system increased the expression of the Col5a1 gene. CONCLUSION: These results provided evidence that miR-29b regulates the Col5a1 gene expression through binding to the 3'UTR, which might play an important role in the pathogenesis of disease related to bone metabolism and fibrogenic reactions.


Assuntos
Colágeno/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica/genética , Expressão Gênica/genética , MicroRNAs/genética , Animais , Linhagem Celular , Células Cultivadas , Colágeno/metabolismo , Camundongos , Osteoblastos/metabolismo , Regiões Promotoras Genéticas/genética
5.
J Sleep Res ; 27(4): e12608, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28960626

RESUMO

Rhythmic masticatory muscle activity can be a normal variant of oromotor activity, which can be exaggerated in patients with sleep bruxism. However, few studies have tested the possibility in naturally sleeping animals to study the neurophysiological mechanisms of rhythmic masticatory muscle activity. This study aimed to investigate the similarity of cortical, cardiac and electromyographic manifestations of rhythmic masticatory muscle activity occurring during non-rapid eye movement sleep between guinea pigs and human subjects. Polysomnographic recordings were made in 30 freely moving guinea pigs and in eight healthy human subjects. Burst cycle length, duration and activity of rhythmic masticatory muscle activity were compared with those for chewing. The time between R-waves in the electrocardiogram (RR interval) and electroencephalogram power spectrum were calculated to assess time-course changes in cardiac and cortical activities in relation to rhythmic masticatory muscle activity. In animals, in comparison with chewing, rhythmic masticatory muscle activity had a lower burst activity, longer burst duration and longer cycle length (P < 0.05), and greater variabilities were observed (P < 0.05). Rhythmic masticatory muscle activity occurring during non-rapid eye movement sleep [median (interquartile range): 5.2 (2.6-8.9) times per h] was preceded by a transient decrease in RR intervals, and was accompanied by a transient decrease in delta elelctroencephalogram power. In humans, masseter bursts of rhythmic masticatory muscle activity were characterized by a lower activity, longer duration and longer cycle length than those of chewing (P < 0.05). Rhythmic masticatory muscle activity during non-rapid eye movement sleep [1.4 (1.18-2.11) times per h] was preceded by a transient decrease in RR intervals and an increase in cortical activity. Rhythmic masticatory muscle activity in animals had common physiological components representing transient arousal-related rhythmic jaw motor activation in comparison to human subjects.


Assuntos
Mastigação/fisiologia , Músculos da Mastigação/fisiologia , Bruxismo do Sono/fisiopatologia , Sono/fisiologia , Adulto , Animais , Nível de Alerta/fisiologia , Eletrocardiografia/métodos , Eletroencefalografia/métodos , Eletromiografia/métodos , Feminino , Cobaias , Humanos , Masculino , Bruxismo do Sono/diagnóstico , Especificidade da Espécie , Fatores de Tempo , Adulto Jovem
6.
Radiat Environ Biophys ; 57(1): 41-54, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29230533

RESUMO

Radiation-induced fibrosis (RIF) is thought to involve the excessive accumulation of collagen and other extracellular matrix components; previously, we reported that ionizing radiation increased the type I collagen expression and that transforming growth factor (TGF)-ß was involved in this increase through activating its downstream mediator, Smad3. A recent study found that microRNAs (miRNAs)-small, noncoding sequences approximately 20 nucleotides long-negatively regulate the gene expression posttranscriptionally, and it has been suggested that miRNAs play essential roles in cellular processes, including fibrosis. However, their role in the development of RIF remains unexplored. In the present study, we examined the effects of miRNA on the expression of type I collagen induced by ionizing radiation and the mechanisms underlying the miRNA expression observed following ionizing radiation. We analyzed the regulation of miRNA following ionizing radiation by an miRNA real-time PCR, and found that miR-29 family members were downregulated in irradiated mouse fibroblasts and directly targeted type I collagen genes by specifically binding to the 3' untranslated region. We also found that the overexpression of miR-29 inhibited the ionizing radiation-induced expression of type I collagen, whereas the knockdown of miR-29 enhanced it. In addition, TGF-ß/Smad-signaling significantly decreased the transcription of miR-29, whereas the inhibition of this signaling pathway cancelled this decrease. In conclusion, miR-29 was involved in the regulation of type I collagen expression through the TGF-ß/Smad-signaling pathway in irradiated cells, suggesting that miR-29 may be an important regulator of RIF.


Assuntos
Colágeno Tipo I/genética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/efeitos da radiação , MicroRNAs/genética , Animais , Sequência de Bases , Regulação para Baixo/genética , Regulação para Baixo/efeitos da radiação , Fibrose , Camundongos , Células NIH 3T3 , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo
7.
JAMA ; 329(17): 1510-1511, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37058313

RESUMO

A 95-year-old farmer taking prednisolone for bullous pemphigoid had 24 hours of abdominal pain, 2 weeks of diarrhea, and 3 months of intermittent abdominal bloating and anorexia. Evaluation showed purpuric macules and small thumbprint-like patches on her upper abdomen and central chest and a white blood cell count of 13 600/µL (89.9% neutrophils, 0.2% eosinophils). What is the diagnosis and what would you do next?


Assuntos
Dor Abdominal , Exantema , Fazendeiros , Púrpura , Idoso de 80 Anos ou mais , Humanos , Dor Abdominal/etiologia , Exantema/etiologia , Penfigoide Bolhoso , Púrpura/etiologia
8.
Biochim Biophys Acta ; 1864(8): 974-82, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26876537

RESUMO

Thioredoxins are nearly ubiquitous disulfide reductases involved in a wide range of biochemical pathways in various biological systems, and also implicated in numerous biotechnological applications. Plants uniquely synthesize an array of thioredoxins targeted to different cell compartments, for example chloroplastic f- and m-type thioredoxins involved in regulation of the Calvin-Benson cycle. The cytosolic h-type thioredoxins act as key regulators of seed germination and are recycled by NADPH-dependent thioredoxin reductase. The present review on thioredoxin h systems in plant seeds focuses on occurrence, reaction mechanisms, specificity, target protein identification, three-dimensional structure and various applications. The aim is to provide a general background as well as an update covering the most recent findings. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.


Assuntos
Germinação/fisiologia , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Sementes/metabolismo , Tiorredoxina h/metabolismo , NADP/metabolismo , Oxirredução , Tiorredoxina Dissulfeto Redutase/metabolismo
9.
Macromol Rapid Commun ; 37(19): 1581-1586, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27511960

RESUMO

The dimensions of nanocelluloses are important factors in controlling their material properties. The present study reports a fast and robust method for estimating the widths of individual nanocellulose particles based on the turbidities of their water dispersions. Seven types of nanocellulose, including short and rigid cellulose nanocrystals and long and flexible cellulose nanofibers, are prepared via different processes. Their widths are calculated from the respective turbidity plots of their water dispersions, based on the theory of light scattering by thin and long particles. The turbidity-derived widths of the seven nanocelluloses range from 2 to 10 nm, and show good correlations with the thicknesses of nanocellulose particles spread on flat mica surfaces determined using atomic force microscopy.


Assuntos
Celulose/química , Nanopartículas/química , Nefelometria e Turbidimetria , Tamanho da Partícula , Propriedades de Superfície
10.
Postgrad Med J ; 97(1150): 542, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32817577
14.
Biochem Biophys Res Commun ; 452(3): 531-6, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25172663

RESUMO

Bone is essentially composed of two components, hydroxyapatite and extracellular matrix proteins. The extracellular matrix of bone is primary composed of collagen, mostly type I collagen, with lesser amounts of other types of collagen such as type V collagen. Osteoblast differentiation is a multi-step process in which many classes of factors function in a coordinated manner. Sp7/Osterix, which binds to G/C-rich sequences, is a transcription factor that contributes to osteoblast differentiation. The present study aimed to clarify the involvement of Sp7/Osterix with the proximal promoter region of the mouse Col1a2 gene containing multiple G/C-rich sequences exist. Consequently, a functional analysis of the proximal mouse Col1a2 promoter showed that a substitution mutation of the second G/C-rich sequence from the transcription site specifically decreased the activity of osteoblastic cells. In addition, the experiments of overexpression of Sp7/Osterix and treatment with its specific siRNA showed that this G/C-rich sequence is responsible for the specific expression in osteoblastic cells. Consistent with these data, Sp7/Osterix bound to the region and increased the expression of the Col1a2 gene in association with osteoblast differentiation in the culture system.


Assuntos
Colágeno Tipo I/genética , Regulação da Expressão Gênica , Osteoblastos/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Animais , Composição de Bases , Sítios de Ligação , Diferenciação Celular , Linhagem Celular , Colágeno Tipo I/metabolismo , Genes Reporter , Luciferases/genética , Luciferases/metabolismo , Camundongos , Mutação , Células NIH 3T3 , Osteoblastos/citologia , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator de Transcrição Sp7 , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo
15.
Electrophoresis ; 35(15): 2229-36, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24737590

RESUMO

Hydrophilic interaction (HI)-based separation like HILIC is effective for analyzing hydrophilic biological samples such as carbohydrates, peptides, and metabolites. To overcome the drawbacks of conventional HILIC such as large consumption of organic solvents and easy deterioration of the separation column, we developed HI electrokinetic chromatography (EKC) by employing bio-based nanomaterials as the hydrophilic pseudostationary phase. By mechanical/chemical treatments, cellulose, chitin, and chitosan were processed to 10-nm wide nanofibers/nanowhiskers (NFs/NWs), which are longer/shorter than 1000/200 nm, respectively. In HI-EKC of oligosaccharides using 0.001% uncharged cellulose NFs, strong interaction was observed for the large-size oligosaccharides with the retention factors (k) of up to 1.56, indicating a HILIC-mode interaction. In HI-EKC with 0.1% positively charged chitosan NFs, benzenedisulfonic acid, benzenesulfonic acid (BS), and p-hydroxy BS (HBS) had k values of 0.036, 0.018, and 0.018, respectively, suggesting that the ion-exchange interaction mainly occurred via sulfonate groups. Finally, HI-EKC was demonstrated using 0.05% chitin or chitosan NWs. In both cases using chitin and chitosan NWs, HBS showed much stronger interaction with k > 0.192 compared with BS with k < 0.070. It indicated structural difference between NFs and NWs affected the HI behavior in terms of both the ion-exchange and HILIC modes.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Nanoestruturas/química , Oligossacarídeos/química , Alcanossulfonatos/química , Celulose/química , Quitina/química , Eletroforese Capilar , Interações Hidrofóbicas e Hidrofílicas , Ácidos Sulfônicos/química
16.
Cell Tissue Bank ; 15(3): 373-80, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23974965

RESUMO

The murine preosteoblastic cell line, MC3T3-E1, is widely used to study bone formation and differentiation in vitro. However, this cell line is unstable in culture. The current study was designed to establish a stable osteoblastic cell line. A mammalian expression vector carrying the SV 40 large T antigen was introduced into a primary culture of cells isolated from the calvaria of newborn mice. Among isolated cell lines, the MN16 cell line was selected for further characterization. The MN16 cell line was cultured for 28 days, and compared with the MC3T3-E1 cell line with or without induction. The expression of bone-related genes was examined using the real-time RT-PCR technique. Alizarin red and von Kossa staining were used to detect mineralization of nodules in the cultures. The cell line showed the characteristics of osteoblastic cells in term of gene expression patterns of various molecular markers and calcium deposition in the cell layer after induction. Furthermore, the MN16 cells showed strong adhesion to the basic domain of collagen, a result that is specific for bone-derived cells. The MN16 cell line was found to be stably differentiated into bone formation cells in vitro and should be useful for studying bone biology.


Assuntos
Antígenos Transformantes de Poliomavirus/metabolismo , Calcificação Fisiológica/fisiologia , Osteoblastos/citologia , Osteogênese/fisiologia , Animais , Osso e Ossos/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Colágeno/metabolismo , Camundongos , Osteoblastos/metabolismo , Osteocalcina/metabolismo
17.
Psychogeriatrics ; 14(2): 87-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24954832

RESUMO

BACKGROUND: Sense of coherence (SOC) is associated with a reduced risk of various health problems and is thought to be a major factor related to the ability to cope with stress. In the present study, we examined the association between caregiver burden and SOC among caregivers to persons with dementia. METHODS: Participants included 274 caregivers or family members of community-dwelling elderly dementia patients. To assess the cognitive function of patients, neuropsychological tests (e.g. Mini-Mental State Examination, Clinical Dementia Rating) were conducted by a clinical psychologist who was well trained in interviewing participants; the tests used a semi-structured interview protocol. Senior neurologists and psychiatrists also independently evaluated the dementia status of patients. To assess the SOC and caregiver burden, a social welfare counsellor asked questions from a 13-item version of the SOC scale and the short, eight-item Japanese version of the Zarit Caregiver Burden Interview (ZBI). RESULTS: Among 78 caregivers of elderly subjects with cognitive impairment due to dementia, the ZBI score was significantly associated with SOC (r = -0.38, P = 0.001). Multiple regression analyses revealed that SOC scores (ß = -0.42, P < 0.001) and Mini-Mental State Examination scores (ß = -0.28, P = 0.009) were significantly associated with ZBI scores (F(2, 76) = 10.51, P < 0.001). SOC was closely associated with personal strain in the ZBI (ß = -0.41, P < 0.001; F(3, 75) = 8.53, P < 0.001). CONCLUSION: Caregivers with a strong SOC may be less prone to experiencing personal strain from their burden. These results suggest that reinforcement of SOC would contribute to reducing the personal strain.


Assuntos
Adaptação Psicológica , Cuidadores/psicologia , Demência/enfermagem , Senso de Coerência , Adulto , Idoso , Idoso de 80 Anos ou mais , Efeitos Psicossociais da Doença , Feminino , Humanos , Entrevistas como Assunto , Japão , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Qualidade de Vida/psicologia , Análise de Regressão , Resiliência Psicológica , Índice de Gravidade de Doença
18.
Foods ; 13(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38672850

RESUMO

Excessive consumption of sugary foods increases the likelihood of obesity, as well as the preventable risk of lifestyle illnesses such as diabetes and cardiovascular diseases. Frequent intake of sweet snacks is considered to increase the risk of overweight/obesity in industrial nations. However, we cannot stop snacking against our better judgment. Therefore, in this study, we sought to develop high-protein, low-carb "mock snacks" to satisfy snack lovers' appetites and nutrition. Soy protein-based, ball-shaped food products with 57.7% (w/w) protein and 3.6% sugar have been developed. The addition of canola oil made them melty in the mouth without sacrificing their crispiness. Moreover, evaluation of the surface topography of the "soy balls" by 3D laser scanning demonstrated their high degree of sphericity. Conclusively, the snacks developed here may be one of the healthy alternatives for the current sugary ones.

19.
PLoS Genet ; 6(12): e1001254, 2010 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-21203496

RESUMO

Glycosylation plays crucial regulatory roles in various biological processes such as development, immunity, and neural functions. For example, α1,3-fucosylation, the addition of a fucose moiety abundant in Drosophila neural cells, is essential for neural development, function, and behavior. However, it remains largely unknown how neural-specific α1,3-fucosylation is regulated. In the present study, we searched for genes involved in the glycosylation of a neural-specific protein using a Drosophila RNAi library. We obtained 109 genes affecting glycosylation that clustered into nine functional groups. Among them, members of the RNA regulation group were enriched by a secondary screen that identified genes specifically regulating α1,3-fucosylation. Further analyses revealed that an RNA-binding protein, second mitotic wave missing (Swm), upregulates expression of the neural-specific glycosyltransferase FucTA and facilitates its mRNA export from the nucleus. This first large-scale genetic screen for glycosylation-related genes has revealed novel regulation of fucTA mRNA in neural cells.


Assuntos
Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Genômica , Animais , Drosophila melanogaster/genética , Glicosilação , Sistema Nervoso/metabolismo , Especificidade de Órgãos
20.
Foods ; 12(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37509895

RESUMO

Extensive and long-term efforts on wheat breeding [...].

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