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1.
Artículo en Inglés | MEDLINE | ID: mdl-35460896

RESUMEN

Na+,K+-ATPase (NKA) α-subunit 1a (α1a) and 1b (α1b) gene expressions in the gills are changeable in response to ambient salinity in a few salmonids. In this study, the expressions were compared among ambient salinities and used to infer sea entry migration of chum salmon Oncorhynchus keta fry. The expression of α1a decreased from the 2 days after seawater (SW) transfer from freshwater (FW) and was significantly lower in SW-acclimated fry than that in FW-fry. On the other hand, the expression of α1b peaked on the first to second day after SW transfer and then settled to a level 2-fold higher than in FW-fry. In fry caught in the waterfronts of the beaches, the expression levels were quite similar to those on the first and second days after SW transfer, whereas, in fry caught off beach, the expressions were identical to those of SW-acclimated fry. These suggest that fry adapt to SW with moving along the shoal in the bay, and move to off beach after completing SW adaptation. One of the physiological significances in a usage of waterfront may be to transform the gills to SW type. Only fry on the 2 days after SW transfer failed to exhibit condition factor-dependency of burst swimming, probably due to physiological perturbation, which may be related to poor predation avoidance. The physiological approach used in this study inferred sea entry migration of fry; furthermore, it shows the possible significance of adaptation to SW in the shoal is to reduce predation risk.


Asunto(s)
Oncorhynchus keta , Animales , Branquias/metabolismo , Iones/metabolismo , Oncorhynchus keta/genética , Salinidad , Agua de Mar , Sodio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
2.
BMC Biotechnol ; 18(1): 79, 2018 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-30541521

RESUMEN

BACKGROUND: Large-scale processing of lignocellulosics for glucose production generally relies on high temperature and acidic or alkaline conditions. However, extreme conditions produce chemical contaminants that complicate downstream processing. A method that mainly rely on mechanical and enzymatic reaction completely averts such problem and generates unmodified lignin. Products from this process could find novel applications in the chemicals, feed and food industry. But a large-scale system suitable for this purpose is yet to be developed. In this study we applied simultaneous enzymatic saccharification and communition (SESC) for the pre-treatment of a representative lignocellulosic biomass, cedar softwood, under both laboratory and large-scale conditions. RESULTS: Laboratory-scale comminution achieved a maximum saccharification efficiency of 80% at the optimum pH of 6. It was possible to recycle the supernatant to concentrate the glucose without affecting the efficiency. During the direct alcohol fermentation of SESC slurry, a high yield of ethanol was attained. The mild reaction conditions prevented the generation of undesired chemical inhibitors. Large-scale SESC treatment using a commercial beads mill system achieved a saccharification efficiency of 60% at an energy consumption of 50 MJ/kg biomass. CONCLUSION: SESC is very promising for the mild and clean processing of lignocellulose to generate glucose and unmodified lignin in a large scale. Economic feasibility is highly dependent on its potential to generate high value natural products for energy, specialty chemicals, feed and food application.


Asunto(s)
Productos Biológicos/química , Biotecnología/métodos , Cedrus/química , Lignina/química , Biocatálisis , Biotecnología/instrumentación , Celulasa/química , Endo-1,4-beta Xilanasas/química , Etanol/química , Hidrólisis , Madera/química , beta-Glucosidasa/química
3.
Chem Pharm Bull (Tokyo) ; 64(7): 772-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27373631

RESUMEN

Enantioselective total synthesis of the proposed structure of furan-containing polyketide was accomplished. The key features include a chemo- and enantioselective epoxidation of 1,4-cyclohexadiene by Shi asymmetric epoxidation, a regioselective epoxide ring opening, chemo- and diastereoselective dihydroxylation of the conjugated dienone derivative, and vinylation of the lactone accompanied by formation of the furan ring.


Asunto(s)
Furanos/química , Policétidos/síntesis química , Estructura Molecular , Policétidos/química , Estereoisomerismo
4.
J Atheroscler Thromb ; 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38925924

RESUMEN

Decades of research have reshaped our understanding of high-density lipoprotein (HDL) , shifting our focus from cholesterol (C) levels to multifaceted functionalities. Epidemiological studies initially suggested an association between HDL-C levels and cardiovascular disease (CVD) risk; however, such a simple association has not been indicated by recent studies. Notably, genome-wide studies have highlighted discrepancies between HDL-C levels and CVD outcomes, urging a deeper exploration of the role of HDL. The key to this shift lies in elucidating the role of HDL in reverse cholesterol transport (RCT), which is a fundamental anti-atherosclerotic mechanism. Understanding RCT has led to the identification of therapeutic targets and novel interventions for atherosclerosis. However, clinical trials have underscored the limitations of HDL-C as a therapeutic target, prompting the re-evaluation of the role of HDL in disease prevention. Further investigations have revealed the involvement of HDL composition in various diseases other than CVD, including chronic kidney disease, Alzheimer's disease, and autoimmune diseases. The anti-inflammatory, antioxidative, and anti-infectious properties of HDL have emerged as crucial aspects of its protective function, opening new avenues for novel biomarkers and therapeutic targets. Omics technologies have provided insights into the diverse composition of HDL, revealing disease-specific alterations in the HDL proteome and lipidome. In addition, combining cell-based and cell-free assays has facilitated the evaluation of the HDL functionality across diverse populations, offering the potential for personalized medicine. Overall, a comprehensive understanding of HDL multifunctionality leads to promising prospects for future clinical applications and therapeutic developments, extending beyond cardiovascular health.

5.
Behav Brain Res ; 458: 114758, 2024 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-37952686

RESUMEN

In the past few decades, neuroscientists have studied the physiological basis of pleasant touch. Unmyelinated low-threshold mechanoreceptors are central to the study of the physiological basis of pleasant touch. Research on pleasant stimuli has mostly focused on passive stimuli, and the brain activation sites for active pleasant stimuli are not clear. Therefore, the purpose of this study was to identify brain activation sites during active pleasant stimulation of hairless skin using functional magnetic resonance imaging. Forty-two healthy subjects aged 19 years or older were asked to actively grasp in five stimulus tasks. The comfort and sensations that occurred during the tasks were investigated using a questionnaire. Significant activation was found in the middle frontal gyrus when the hair ball and slime ball were grasped, while there was significant activation in the amygdala when grasping a squeeze ball compared to the tennis ball. In a questionnaire survey of the subjects, there was a significant difference in the comfort score between the tennis ball and the squeeze ball, but no significant correlation was found between the comfort scores and the brain sites of activation. Therefore, although active stimulation with the squeeze ball significantly activated the amygdala, it was not clear that the amygdala was significantly activated by active pleasant stimulation. In the future, it will be necessary to investigate the texture of the squeeze ball in more detail, and to increase the number of subjects for further study.


Asunto(s)
Encéfalo , Percepción del Tacto , Humanos , Encéfalo/fisiología , Piel , Tacto/fisiología , Percepción del Tacto/fisiología , Emociones/fisiología , Imagen por Resonancia Magnética/métodos , Estimulación Física/métodos
6.
J Atheroscler Thromb ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38749717

RESUMEN

Abetalipoproteinemia (ABL) is a rare disease characterized by extremely low apolipoprotein B (apoB)-containing lipoprotein levels, dietary fat, and fat-soluble vitamin malabsorption, leading to gastrointestinal, neuromuscular, and ophthalmological symptoms. We herein report a case of ABL with novel compound heterozygous mutations in the microsomal triglyceride transfer protein gene (c.1686_1687del [p.Ser563TyrfsTer10] and c.1862T>C [p.Ile621Thr]), identified via panel sequencing. Although the patient had extremely reduced low-density lipoprotein cholesterol levels and a fatty liver, he did not exhibit other typical complications. Furthermore, unlike typical ABL, this patient had a preserved apoB-48 secretion and increased concentrations of high-density lipoprotein cholesterol, which may account for the normal serum fat-soluble vitamin levels.

7.
Front Hum Neurosci ; 17: 1249176, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38116234

RESUMEN

Background: Autonomous sensory meridian response (ASMR) is a sensory response such as tingling and pleasantness from audiovisual stimuli. ASMR videos come in a wide variety of types, and personal preferences are biased. There are many reports of the effects os ASMR on sleep onset, anxiety relief, and other relaxation effects. However, prior task-oriented studies have used ASMR videos provided by the experimenter. We hypothesized that ASMR movies of a personal preference would show significantly increased activity in the nucleus accumbens, frontal cortex, and insular cortex, which are brain areas associated with relaxation. Therefore, the purpose of this study was to elucidate the neuroscientific basis for the relaxation effects of ASMR videos that match someone's personal preferences. Methods: This study included 30 healthy individuals aged ≥18 years. ASMR enthusiasts were included as the target population due to the need to have a clear preference for ASMR videos. A control video (1 type) and ASMR videos (20 types) were used as the stimulus tasks. Among the ASMR videos, those with high and low evaluation scores were considered liked and dislikedASMR videos, respectively. Functional magnetic resonance imaging was performed while the participants viewed a block design with a resting task in between. The data were analyzed using Statistical Parametric Mapping 12 to identify the areas activated by control, disliked, and liked ASMR videos. Results: Emotion-related areas (the amygdala, frontal cortex, and insular cortex) not activated by control and unliked ASMR videos were activated only by liked ASMR videos. Conclusion: The amygdala, frontal cortex, and insular cortex may be involved in the limbic dopamine circuits of the amygdala and middle frontal gyrus and the autonomic balance of the left and right insular cortices. This suggests the potential of positive mood and its use as a treatment for patients with anxiety and depression. These results suggest that the use of ASMR videos to match individual preferences may induce relaxation and have beneficial effects on depression and other disorders, and also support the introduction of ASMR videos in mental health care.

8.
Biomolecules ; 13(2)2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36830597

RESUMEN

Cholesterol efflux is a major atheroprotective function of high-density lipoproteins (HDLs) which removes cholesterol from the foam cells of lipid-rich plaques in Type 2 diabetes. The dipeptidyl peptidase-4 (DPP-4) inhibitor sitagliptin phosphate increases plasma glucagon-like peptide-1 (GLP-1) concentrations and is used to treat Type 2 diabetes. GLP-1 plays an important role in regulating insulin secretion and expression via the GLP-1 receptor (GLP-1R), which is expressed in pancreatic islets as well as freshly isolated human monocytes and THP-1 cells. Here, we identified a direct role of GLP-1 and DPP-4 inhibition in HDL function. Cholesterol efflux was measured in cultivated phorbol 12-myristate 13-acetate-treated THP-1 cells radiolabeled with 3H-cholesterol and stimulated with liver X receptor/retinoid X receptor agonists. Contrary to vildagliptin, sitagliptin phosphate together with GLP-1 significantly (p < 0.01) elevated apolipoprotein (apo)A1-mediated cholesterol efflux in a dose-dependent manner. The sitagliptin-induced increase in cholesterol efflux did not occur in the absence of GLP-1. In contrast, adenosine triphosphate-binding cassette transporter A1 (ABCA1) mRNA and protein expressions in the whole cell fraction were not changed by sitagliptin in the presence of GLP-1, although sitagliptin treatment significantly increased ABCA1 protein expression in the membrane fraction. Furthermore, the sitagliptin-induced, elevated efflux in the presence of GLP-1 was significantly decreased by a GLP-1R antagonist, an effect that was not observed with a protein kinase A inhibitor. To our knowledge, the present study reports for the first time that sitagliptin elevates cholesterol efflux in cultivated macrophages and may exert anti-atherosclerotic actions that are independent of improvements in glucose metabolism. Our results suggest that sitagliptin enhances HDL function by inducing a de novo HDL synthesis via cholesterol efflux.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Humanos , Fosfato de Sitagliptina , Diabetes Mellitus Tipo 2/metabolismo , Células THP-1 , Hipoglucemiantes , Péptido 1 Similar al Glucagón/metabolismo , Colesterol/metabolismo , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas
9.
J Biosci Bioeng ; 136(6): 477-486, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37923618

RESUMEN

Changes in cell fluidity have been observed in various cellular tissues and are strongly linked to biological phenomena such as self-organization. Recent studies suggested variety of mechanisms and factors, which are still being investigated. This study aimed to investigate changes in cell fluidity in multi-layered cell sheets, by exploring the collective arrest of cell motion and its release in cultures of corneal epithelial cells. We constructed mathematical models to simulate the behaviors of individual cells, including cell differentiation and time-dependent changes in cell-cell connections, which are defined by stochastic or kinetic rules. Changes in cell fluidity and cell sheet structures were expressed by simulating autonomous cell behaviors and interactions in tissues using an agent-based model. A single-cell level spatiotemporal analysis of cell state transition between migratable and non-migratable states revealed that the release from collective arrest of cell motion was initially triggered by a decreased ability to form cell-cell connections in the suprabasal layers, and was propagated by chain migration. Notably, the disruption of cell-cell connections and stratification occurred in the region of migratable state cells. Hence, a modeling approach that considers time-dependent changes in cell properties and behavior, and spatiotemporal analysis at the single-cell level can effectively delineate emergent phenomena arising from the complex interplay of cells.


Asunto(s)
Células Epiteliales , Modelos Biológicos , Movimiento Celular
10.
Front Nutr ; 10: 1297008, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38260075

RESUMEN

Policosanol supplementation has been reported to increase high-density lipoprotein (HDL)-cholesterol (HDL-C). However, the association between Cuban policosanol supplementation and HDL cholesterol efflux capacity (CEC), an important function of HDL, remains unclear. We performed a lipoprotein analysis investigating 32 Japanese healthy participants (placebo, n = 17 or policosanol supplementation for 12 weeks, n = 15) from a randomized Cuban policosanol clinical trial. First, HDL CEC and HDL-related factors were measured before and after policosanol supplementation. Then, through electron microscopy after ultracentrifugation and high-performance liquid chromatography, HDL morphology and subclass were analyzed, respectively. Finally, the effects of policosanol supplementation regarding HDL function, HDL-related factors, and HDL morphology/component were examined. Cuban policosanol considerably increased the HDL CEC and HDL-C and apolipoprotein A-I (ApoA-I) levels. Furthermore, policosanol supplementation led to larger HDL particles, increased cholesterol content in larger HDL particles, and reduced triglyceride content in smaller HDL particles. In participants with high baseline HDL-C levels, the policosanol effects for HDL CEC are observed. HDL CEC fluctuation induced by policosanol was highly associated with HDL-C and ApoA-I changes. In conclusion, for the first time, we demonstrated that policosanol supplementation increased the HDL CEC in healthy participants.

11.
J Atheroscler Thromb ; 30(8): 1070-1082, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36384970

RESUMEN

Lecithin-cholesterol acyltransferase (LCAT) plays a significant role in the progression from premature to mature high-density lipoprotein (HDL) in circulation. Consequently, primary or secondary LCAT deletion or reduction naturally results in low serum HDL cholesterol levels. Recently, rare cases of acquired HDL deficiency with LCAT autoantibodies have been reported, mainly from Japan, where LCAT autoantibodies of immunoglobulin G (IgG) caused the HDL deficiency. Here to our knowledge, we report for the first time two cases of acquired HDL deficiency caused by IgG4 linked LCAT autoantibodies with or without a high serum IgG4 level. Furthermore, these cases can extend to a new concept of "IgG4 autoimmune disease" from the viewpoint of verifying the serum autoantibody and/or renal histopathology.


Asunto(s)
Deficiencia de la Lecitina Colesterol Aciltransferasa , Lecitinas , Humanos , Esterol O-Aciltransferasa , Autoanticuerpos , Fosfatidilcolina-Esterol O-Aciltransferasa , Lipoproteínas HDL , Inmunoglobulina G , HDL-Colesterol
12.
J Clin Lipidol ; 16(5): 596-600, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35931648

RESUMEN

Here, we present the first case of a Japanese patient with familial hypobetalipoproteinemia (HBL) that is caused by homozygous loss-of-function mutations in proprotein convertase subtilisin/kexin type 9 (PCSK9). A 46-year-old female patient who was born in a consanguineous marriage of parents who were second cousins was referred to our hospital due to decreased low-density lipoprotein (LDL)-cholesterolemia (22 mg/dL). She did not have any secondary HBL causes. Novel homozygous mutations were identified in PCSK9 (c.1133G>A [p.Cys378Tyr]) using panel sequencing. The serum levels of heterodimer PCSK9 and furin-cleaved PCSK9 were extremely low (<32 and 15 ng/mL, respectively), leading to the diagnosis of familial HBL diagnosis caused by loss-of-function mutations in PCSK9. The patient did not exhibit any complications associated with low LDL cholesterol, except for mild fatty liver and reduced serum 25-OH vitamin D level (15.7 ng/mL). Here, we provide a detailed molecular and functional characterization of a novel loss-of-function mutation in PCSK9.


Asunto(s)
Hipobetalipoproteinemias , Proproteína Convertasa 9 , Femenino , Humanos , Persona de Mediana Edad , Proproteína Convertasa 9/genética , Proproteína Convertasas , LDL-Colesterol , Serina Endopeptidasas/genética , Hipobetalipoproteinemias/diagnóstico , Hipobetalipoproteinemias/genética , Mutación
13.
Front Cardiovasc Med ; 9: 942772, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36003908

RESUMEN

Type 1 familial hypobetalipoproteinemia (FHBL1), characterized by low levels of apolipoprotein B (ApoB)-containing lipoproteins, elevation of transaminases, and hepatic steatosis, is a rare disease the prevalence of which is 1 in 3,000 among general population. Here we report an extremely rare family where phenotypes of familial hypercholesterolemia (FH) are canceled by coexistence of FHBL1 caused by an truncating mutation in apolipoprotein B (APOB).

14.
J Biosci Bioeng ; 131(3): 305-313, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33262019

RESUMEN

During culture with feeder cells, deviation from the undifferentiated state of human induced pluripotent stem cells (hiPSCs) occurs at a very low frequency. Anomalous cell migration in central and peripheral regions of hiPSC colonies has been suggested to be the trigger for this phenomenon. To confirm this hypothesis, sequential cell migration prior to deviation must be demonstrated. This has been difficult using in vitro methods. We therefore developed a kinetic model with a proposed definition of anomalous cell migration as continuous relatively fast or slow cell migration. The developed model was validated via in silico reproduction of deviation phenomenon observed in vitro, such as the positions of deviated cells in a colony and the frequency of deviation in culture. This model suggests that anomalous cell migration-driven hiPSC deviation can be explained by two factors: a mechanical stimulus, represented by cell migration, and duration of the mechanical stimulus. The factor "duration of mechanical stimulus" sets our model apart from others, and helps to realize the ultra-rare trigger (approximately 10-5) of deviation from the undifferentiated state in hiPSC culture.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Modelos Biológicos , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Células Nutrientes/citología , Humanos , Cinética
16.
Sci Rep ; 10(1): 9282, 2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32518325

RESUMEN

Corneal limbal epithelial stem cell transplantation using cultivated human corneal epithelial cell sheets has been used successfully to treat limbal stem cell deficiencies. Here we report an investigation into the quality of cultivated human corneal epithelial cell sheets using time-lapse imaging of the cell culture process every 20 minutes over 14 days to ascertain the level of cell jamming, a phenomenon in which cells become smaller, more rounded and less actively expansive. In parallel, we also assessed the expression of p63, an important corneal epithelial stem cell marker. The occurrence of cell jamming was variable and transient, but was invariably associated with a thickening and stratification of the cell sheet. p63 was present in all expanding cell sheets in the first 9 days of culture, but it's presence did not always correlate with stratification of the cell sheet. Nor did p63 expression necessarily persist in stratified cell sheets. An assessment of cell jamming, therefore, can shed significant light on the quality and regenerative potential of cultivated human corneal epithelial cell sheets.


Asunto(s)
Enfermedades de la Córnea/terapia , Epitelio Corneal/citología , Proteínas de la Membrana/metabolismo , Trasplante de Células Madre , Células Madre/citología , Células 3T3 , Animales , Ingeniería Biomédica/métodos , Diferenciación Celular/fisiología , Línea Celular , Proliferación Celular/fisiología , Células Epiteliales/citología , Femenino , Humanos , Limbo de la Córnea/citología , Masculino , Ratones , Persona de Mediana Edad
17.
Bioresour Technol ; 300: 122622, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31891856

RESUMEN

Simultaneous enzymatic saccharification and comminution (SESC) was used for large-scale anaerobic digestion of wood lignocellulose to generate methane and unmodified lignin. During SESC, 10% aqueous mixture of powdered debarked wood from various species was subjected to bead milling with hydrolytic enzymes to generate particles below 1 µm. This slurry was directly used as a cosubstrate for anaerobic digestion in a 500 L stirred-tank reactor. Temperature and hydraulic retention time (HRT) were maintained at 50 °C and 30 days, respectively. At stable operation periods, an average yield of 224 L of methane per kg of cedar was attained. Comparable yields were achieved with red pine, elm, oak, and cedar bark. High-throughput microbial analysis established the presence of a relevant community to support the elevated level of methane production. The stability of the unmodified lignin in anaerobic digestion was also confirmed, allowing for its recovery as an important by-product.


Asunto(s)
Lignina , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Metano , Madera
20.
J Biosci Bioeng ; 127(5): 625-632, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30502118

RESUMEN

Maintaining the homogeneity of a stem cell population is one of the challenges in bioprocessing prior to therapeutic applications of stem cells. Concerning human induced pluripotent stem cell (hiPSC) colonies cultured on feeder cells, cells at the peripheral region of the colony were found to have a higher average movement rate than cells at the central region of the colony. This spatial difference in average movement rate might lead to spatial heterogeneity of cell fate decision in the colony. We have developed a kinetic model to clarify the origin of this phenomenon which was difficult to understand by in vitro studies alone. Using a kinetic model based on a cellular automaton, we described fundamental cell behaviors including cell division, contact inhibition, cell migration, cell-cell connections, and cell-substrate connections. With all parameter values estimated from experimental data, the appropriateness of our kinetic model was indicated by good agreement between simulated and experimental data. Using the kinetic model, the average cell movement rate in a colony became homogenous after cell division stopped, implying that cell division was the main cause of the observed spatial heterogeneity. The result also showed a directly proportional relationship between the frequency of cell pushing and cell movement rate in the colony, confirming the role of cell division. Our kinetic model is expected to be useful for studying behaviors of hiPSCs and proposing good strategies to improve hiPSC bioprocessing.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Células Nutrientes/química , Células Nutrientes/citología , Humanos , Células Madre Pluripotentes Inducidas/química , Cinética , Modelos Biológicos
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