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1.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38612551

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a solid-tumor malignancy. To enhance the treatment landscape of PDAC, a 3D model optimized for rigorous drug screening is essential. Within the PDAC tumor microenvironment, a dense stroma comprising a large extracellular matrix and cancer-associated fibroblasts (CAFs) is well-known for its vital role in modulating tumor growth, cellular heterogeneity, bidirectional paracrine signaling, and chemoresistance. In this study, we employed a fibroblast-populated collagen lattice (FPCL) modeling approach that has the ability to replicate fibroblast contractility in the collagenous matrix to build dense stroma. This FPCL model allows CAF differentiation by facilitating multifaceted cell-cell interactions between cancer cells and CAFs, with the differentiation further influenced by mechanical forces and hypoxia carried within the 3D structure. Our FPCL models displayed hallmark features, including ductal gland structures and differentiated CAFs with spindle shapes. Through morphological explorations alongside in-depth transcriptomic and metabolomic profiling, we identified substantial molecular shifts from the nascent to mature model stages and potential metabolic biomarkers, such as proline. The initial pharmacological assays highlighted the effectiveness of our FPCL model in screening for improved therapeutic strategies. In conclusion, our PDAC modeling platform mirrors complex tumor microenvironmental dynamics and offers an unparalleled perspective for therapeutic exploration.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Microambiente Tumoral , Páncreas , Hormonas Pancreáticas , Colágeno
2.
Phys Rev Lett ; 129(14): 144502, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36240410

RESUMEN

Nonlinear wave focusing originating from the universal modulation instability (MI) is responsible for the formation of strong wave localizations on the water surface and in nonlinear wave guides, such as optical Kerr media and plasma. Such extreme wave dynamics can be described by breather solutions of the nonlinear Schrödinger equation (NLSE) like by way of example the famed doubly-localized Peregrine breathers (PB), which typify particular cases of MI. On the other hand, it has been suggested that the MI relevance weakens when the wave field becomes broadband or directional. Here, we provide experimental evidence of nonlinear and distinct PB-type focusing in standing water waves describing the scenario of two counterpropagating wave trains. The collected collinear wave measurements are in excellent agreement with the hydrodynamic coupled NLSE (CNLSE) and suggest that MI can undisturbedly prevail during the interplay of several wave systems and emphasize the potential role of exact NLSE solutions in extreme wave formation beyond the formal narrow band and unidirectional limits. Our work may inspire further experimental investigations in various nonlinear wave guides governed by CNLSE frameworks as well as theoretical progress to predict strong wave coherence in directional fields.

3.
Geophys Res Lett ; 41(14): 5106-5113, 2014 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-25821268

RESUMEN

Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of best hindcast results, the storm surge level was 5-6 m and local amplification of water surface elevation due to seiche was found to be significant inside Leyte Gulf. The numerical experiments show the coherent structure of the storm surge profile due to the specific bathymetry of Leyte Gulf and the Philippines Trench as a major contributor to the disaster in Tacloban. The numerical results also indicated the sensitivity of storm surge forecast.

4.
Sci Data ; 11(1): 786, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019890

RESUMEN

An earthquake with a moment magnitude of 7.5 (Mw) struck the northern Noto Peninsula, Ishikawa Prefecture, Japan, at 16:10 local time on January 1, 2024. This earthquake triggered a tsunami that propagated along the coastline of Ishikawa, Toyama, and Niigata Prefectures facing the Sea of Japan and significantly damaged coastal communities and infrastructure. Approximately 70 researchers from 23 universities or other institutes throughout Japan formed a joint research group to conduct a post-tsunami survey along a 340 km stretch of the coast. Based on the watermarks and traces of the tsunami, the inundation and run-up heights were surveyed using total stations, automatic optical levels, laser range finders, and a real-time kinematic (RTK) Global Navigation Satellite System (GNSS). The tidal correction was adjusted using astronomical tidal tables. In total, 303 survey records have been compiled, generating the NP2024TS (Noto Peninsula 2024 Tsunami Survey) dataset. This dataset provides comprehensive information on the inundation and run-up heights of the tsunami, which is useful for understanding tsunami characteristics and validating numerical tsunami models.

5.
Sci Data ; 10(1): 362, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280216

RESUMEN

The d4PDF-WaveHs dataset represents the first single model initial-condition large ensemble of historical significant ocean wave height (Hs) at a global scale. It was produced using an advanced statistical model with predictors derived from Japan's d4PDF ensemble of historical simulations of sea level pressure. d4PDF-WaveHs provides 100 realizations of Hs for the period 1951-2010 (hence 6,000 years of data) on a 1° × 1° lat.-long. grid. Technical comparison of model skill against modern reanalysis and other historical wave datasets was undertaken at global and regional scales. d4PDF-WaveHs provides unique data to understand better the poorly known role of internal climate variability in ocean wave climate, which can be used to estimate better trend signals. It also provides a better sampling of extreme events. Overall, this is crucial to properly assess wave-driven impacts, such as extreme sea levels on low-lying populated coastal areas. This dataset may be of interest to a variety of researchers, engineers and stakeholders in the fields of climate science, oceanography, coastal management, offshore engineering, and energy resource development.

6.
Cancers (Basel) ; 14(6)2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35326527

RESUMEN

Cancer-associated fibroblasts (CAFs) in the tumor microenvironment perform glycolysis to produce energy, i.e., ATP. Since the origin of CAFs is unidentified, it is not determined whether the intracellular metabolism transitions from oxidative phosphorylation (OXPHOS) to glycolysis when normal tissue fibroblasts differentiate into CAFs. In this study, we established an experimental system and induced the in vitro differentiation of mesenchymal stem cells (MSCs) to CAFs. Additionally, we performed metabolomic and RNA-sequencing analyses before and after differentiation to investigate changes in the intracellular metabolism. Consequently, we discovered that OXPHOS, which was the primary intracellular metabolism in MSCs, was reprogrammed to glycolysis. Furthermore, we analyzed the metabolites in pancreatic tumor tissues in a mice model. The metabolites extracted as candidates in the in vitro experiments were also detected in the in vivo experiments. Thus, we conclude that normal tissue fibroblasts that differentiate into CAFs undergo a metabolic reprogramming from OXPHOS to glycolysis. Moreover, we identified the CAF-specific metabolites expressed during metabolic reprogramming as potential future biomarkers for pancreatic cancer.

7.
Biomedicines ; 10(10)2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36289649

RESUMEN

Scars are composed of stiff collagen fibers, which contract strongly owing to the action of myofibroblasts. To explore the substances that modulate scar contracture, the fibroblast-populated collagen lattice (FPCL) model has been used. However, the molecular signature of the patient-derived FPCL model has not been verified. Here, we examined whether the patient-derived keloid FPCL model reflects scar contraction, analyzing detailed gene expression changes using comprehensive RNA sequencing and histological morphology, and revealed that these models are consistent with the changes during human scar contracture. Moreover, we examined whether conditioned media derived from adipose stem cells (ASC-CM) suppress the scar contracture of the collagen disc. Detailed time-series measurements of changes in disc area showed that the addition of ASC-CM significantly inhibited the shrinkage of collagen discs. In addition, a deep sequencing data analysis revealed that ASC-CM suppressed inflammation-related gene expression in the early phase of contraction; in the later phase, this suppression was gradually replaced by extracellular matrix (ECM)-related gene expression. These lines of data suggested the effectiveness of ASC-CM in suppressing scar contractures. Therefore, the molecular analysis of the ASC-CM actions found in this study will contribute to solving medical problems regarding pathological scarring in wound prognosis.

8.
Micromachines (Basel) ; 12(4)2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33920367

RESUMEN

Artificial vascularized tubular liver tissue has perfusable blood vessels that allow fluid access to the tissue interior, enabling the injection of drugs and collection of metabolites, which are valuable for drug discovery. It is amenable to standard evaluation methods, such as paraffin-embedded sectioning, qPCR, and RNA sequencing, which makes it easy to implement into existing research processes. However, the application of tissues vascularized by the self-assembly of cells, (including tubular liver tissue, has not yet been tested in comprehensive proteomic analysis relevant for drug discovery. Here, we established a method to efficiently separate cells from the tubular liver tissue by adding a pipetting step during collagenase treatment. By using this method, we succeeded in obtaining a sufficient number of cells for the proteomic analysis. In addition, to validate this approach, we compared the cells separated from the tissue with those grown in 2D culture, focusing on the proteins related to drug metabolism. We found that the levels of proteins involved in metabolic phases II and III were slightly higher in the tubular liver tissue than those in the 2D cell culture. Taken together, our suggested method demonstrates the applicability of tubular liver tissue to the proteomic analysis in drug assays.

9.
Sci Rep ; 11(1): 8818, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33893362

RESUMEN

Raman scattering represents the distribution and abundance of intracellular molecules, including proteins and lipids, facilitating distinction between cellular states non-invasively and without staining. However, the scattered light obtained from cells is faint and cells have complex structures, making it difficult to obtain a Raman spectrum covering the entire cell in a short time using conventional methods. This also prevents efficient label-free cell classification. In the present study, we developed the Paint Raman Express Spectroscopy System, which uses two fast-rotating galvano mirrors to obtain spectra from a wide area of a cell. By using this system and applying machine learning, we were able to acquire broad spectra of a variety of human and mouse cell types, including pluripotent stem cells and confirmed that each cell type can be classified with high accuracy. Moreover, we classified different activation states of human T cells, despite their similar morphology. This system could be used for rapid and low-cost drug evaluation and quality management for drug screening in cell-based assays.


Asunto(s)
Células/clasificación , Espectrometría Raman/métodos , Animales , Humanos , Aprendizaje Automático , Ratones , Análisis de la Célula Individual/métodos
10.
Sci Rep ; 11(1): 4690, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33633222

RESUMEN

Cancer-associated fibroblasts (CAFs) are the key components of the densely proliferated stroma in pancreatic ductal adenocarcinoma (PDAC) and contribute to tumor progression and drug resistance. CAFs comprise heterogeneous subpopulations playing unique and vital roles. However, the commonly used mouse models have not been able to fully reproduce the histological and functional characteristics of clinical human CAF. Here, we generated a human cell-derived stroma-rich CDX (Sr-CDX) model, to reproduce the clinical tumor microenvironment. By co-transplanting human adipose-derived mesenchymal stem cells (AD-MSCs) and a human PDAC cell line (Capan-1) into mice, the Sr-CDX model recapitulated the characteristics of clinical pancreatic cancer, such as accelerated tumor growth, abundant stromal proliferation, chemoresistance, and dense stroma formed from the heterogeneous CAFs. Global RNA sequencing, single-cell based RNA sequencing, and histological analysis of CAFs in the Sr-CDX model revealed that the CAFs of the Sr-CDX mice were derived from the transplanted AD-MSCs and composed of heterogeneous subpopulations of CAF, including known and unknown subtypes. These lines of evidences suggest that our new tumor-bearing mouse model has the potential to address an open question in CAF research, that is the mechanism of CAF differentiation.


Asunto(s)
Tejido Adiposo/citología , Diferenciación Celular , Fibroblastos/citología , Xenoinjertos , Células Madre Mesenquimatosas/citología , Células del Estroma/citología , Animales , Carcinoma Ductal Pancreático/patología , Humanos , Ratones , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas
11.
FEBS Open Bio ; 10(10): 1985-2002, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32794647

RESUMEN

Tubular 3D liver tissue with enhanced capillary-like structures branching from a large main channel is potentially useful for drug discovery because the perfusable main channel and capillary-like structures enable mass transfer into and out from the tissue. Tubular liver tissue is comprised of the hepatocellular carcinoma cell line HepG2, human umbilical vein endothelial cells (HUVECs), and mesenchymal stem cells (MSCs), using a perfusion device functioning as the interface for an external pump. This study aimed to compare the expression of genes involved in drug metabolism between 2D-cultured hepatocellular carcinoma cells and 3D-cultured tubular liver tissue. Gene expression profiles of 2D-cultured cells and tubular liver tissue were compared using RNA sequencing. Multidimensional scaling analysis revealed that culture dimensionality had a more prominent effect on gene expression profiles than perfusion conditions. More specifically, genes involved in drug metabolism such as CYP2D6, CYP2E1, NNMT, and SLC28A1 were slightly upregulated in the 3D cultures, while certain genes such as ALDH1B1, ALDH1A2, and SULT1E1 were downregulated. These results indicate that gene expression profiles are largely influenced by culture dimensionality and are potentially useful to researchers intending to switch from 2D culture to 3D culture of hepatocellular carcinoma or other tissue types.


Asunto(s)
Activación Metabólica/genética , Técnicas de Cultivo de Célula/métodos , Organoides/metabolismo , Carcinoma Hepatocelular/metabolismo , Técnicas de Cocultivo , Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/genética , Células Hep G2 , Hepatocitos/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hígado/metabolismo , Neoplasias Hepáticas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Organoides/efectos de los fármacos , Perfusión , Preparaciones Farmacéuticas/metabolismo
12.
FEBS Open Bio ; 10(11): 2268-2281, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32931156

RESUMEN

Cancer-associated fibroblasts (CAFs) are key components of the dense, proliferating stroma observed in pancreatic ductal adenocarcinoma (PDAC), and CAF subpopulations drive tumor heterogeneity and play a major role in PDAC progression and drug resistance. CAFs consist of heterogenous subpopulations such as myoblastic CAF (myCAF) and inflammatory CAF (iCAF), and each has distinct essential roles. However, it is not clear how CAF subpopulations are formed in PDAC. Adipose-derived MSCs (AD-MSCs), which possess a high multilineage potential and self-renewal capacity, are reported to be one of the in vivo CAF sources. Here, we aimed to investigate whether AD-MSCs can act as precursors for CAFs in vitro. We recorded morphological features and collected omics data from two in vitro co-culture models for recapitulating clinical PDAC. Additionally, we tested the advantages of the co-culture model in terms of accurately modeling morphology and CAF heterogeneity. We showed that AD-MSCs differentiate into two distinct CAF subpopulations: Direct contact co-culture with PDAC cell line Capan-1 induced differentiation into myCAFs and iCAFs, while indirect co-culture induced differentiation into only iCAFs. Using these co-culture systems, we also identified novel CAF markers that may be helpful for elucidating the mechanisms of CAFs in the tumor microenvironment (TME). In conclusion, AD-MSCs can differentiate into distinct CAF subtypes depending on the different co-culture conditions in vitro, and the identification of potential CAF markers may aid in future investigations of the mechanisms underlying the role of CAFs in the TME.


Asunto(s)
Fibroblastos Asociados al Cáncer/patología , Diferenciación Celular , Células Madre Mesenquimatosas/patología , Neoplasias Pancreáticas/patología , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Diferenciación Celular/genética , Línea Celular , Línea Celular Tumoral , Forma de la Célula , Técnicas de Cocultivo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Mioblastos/patología , Neoplasias Pancreáticas/genética , Transcriptoma/genética , Neoplasias Pancreáticas
13.
Sci Rep ; 10(1): 5646, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32286353

RESUMEN

Although various production methods for 3D vascularised tissues have been developed, constructing capillary-like structures branching from perfusable large channels remains difficult. This study describes a method to fabricate tube-shaped 3D liver-like tissue (tubular liver tissue) with large channels and capillary-like structures using a perfusion device. The perfusion device functions as an interface between the tissue and an external pump, as it has connectors equipped with anchors that hold the tissue in response to its shrinkage, which is accompanied by the self-organisation of capillary-like structures. Histological analysis revealed that perfusion via the large channel induced capillary formation around the channel and maintained proper tissue functions. Accompanied by structural examinations, global gene expression analysis supported this finding; specifically, genes involved in angiogenesis were enriched in the perfused condition. Furthermore, we confirmed the penetrability of the capillary-like structures by infusing India ink, as well as substance exchange by measuring the amounts of secreted albumin. These lines of evidence indicate that our method can be used to construct 3D tissues, which is useful for fields of in vitro tissue regeneration for drug development and regenerative medicine.


Asunto(s)
Órganos Artificiales , Hígado/irrigación sanguínea , Ingeniería de Tejidos/métodos , Vasos Sanguíneos/anatomía & histología , Capilares/anatomía & histología , Células Hep G2 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células Madre Mesenquimatosas , Perfusión
14.
Sci Data ; 7(1): 105, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32221302

RESUMEN

This dataset, produced through the Coordinated Ocean Wave Climate Project (COWCLIP) phase 2, represents the first coordinated multivariate ensemble of 21st Century global wind-wave climate projections available (henceforth COWCLIP2.0). COWCLIP2.0 comprises general and extreme statistics of significant wave height (HS), mean wave period (Tm), and mean wave direction (θm) computed over time-slices 1979-2004 and 2081-2100, at different frequency resolutions (monthly, seasonally and annually). The full ensemble comprising 155 global wave climate simulations is obtained from ten CMIP5-based state-of-the-art wave climate studies and provides data derived from alternative wind-wave downscaling methods, and different climate-model forcing and future emissions scenarios. The data has been produced, and processed, under a specific framework for consistency and quality, and follows CMIP5 Data Reference Syntax, Directory structures, and Metadata requirements. Technical comparison of model skill against 26 years of global satellite measurements of significant wave height has been undertaken at global and regional scales. This new dataset provides support for future broad scale coastal hazard and vulnerability assessments and climate adaptation studies in many offshore and coastal engineering applications.

15.
Biofabrication ; 11(1): 011001, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30431022

RESUMEN

This study describes a perfusable and stretchable culture system for a skin-equivalent. The system is comprised of a flexible culture device equipped with connections that fix vascular channels of the skin-equivalent and functions as an interface for an external pump. Furthermore, a stretching apparatus for the culture device can be fabricated using rapid prototyping technologies, which allows for easy modifications of stretching parameters. When cultured under dynamically stretching and perfusion conditions, the skin-equivalent exhibits improved morphology. The epidermal layer becomes thicker and more differentiated than that cultured without the stretching stimuli or under statically-stretched conditions, and the dermal layer was more densely populated with dermal fibroblasts than that cultured without perfusion due to the nutrient and oxygen supply by perfusion via the vascular channels. Therefore, the system is useful for the improvement and biological studies of skin-equivalents.


Asunto(s)
Bioimpresión/métodos , Técnicas de Cultivo de Célula/métodos , Queratinocitos/química , Piel/química , Bioimpresión/instrumentación , Técnicas de Cultivo de Célula/instrumentación , Diferenciación Celular , Células Cultivadas , Dermis/química , Dermis/citología , Dermis/metabolismo , Elasticidad , Fibroblastos/química , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Queratinocitos/citología , Queratinocitos/metabolismo , Oxígeno/metabolismo , Impresión Tridimensional/instrumentación , Piel/citología , Piel/metabolismo
16.
Micromachines (Basel) ; 9(6)2018 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-30424236

RESUMEN

This study proposes a microfluidic spinning method to form alginate microfibers with branched and chained structures by controlling two streams of a sodium alginate solution extruded from a theta-glass capillary (a double-compartmented glass capillary). The two streams have three flow regimes: (i) a combined flow regime (single-threaded stream), (ii) a separated flow regime (double-threaded stream), and (iii) a chained flow regime (stream of repeating single- and double-threaded streams). The flow rate of the sodium alginate solution and the tip diameter of the theta-glass capillary are the two parameters which decide the flow regime. By controlling the two parameters, we form branched (a Y-shaped structure composed of thick parent fiber and permanently divided two thin fibers) and chained (a repeating structure of single- and double-threaded fibers with constant frequency) alginate microfibers with various dimensions. Furthermore, we demonstrate the applicability of the alginate microfibers as sacrificial templates for the formation of chain-shaped microchannels with two inlets. Such microchannels could mimic the structure of blood vessels and are applicable for the research fields of fluidics including hemodynamics.

17.
Biomaterials ; 116: 48-56, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27914266

RESUMEN

This paper describes a method for fabricating perfusable vascular channels coated with endothelial cells within a cultured skin-equivalent by fixing it to a culture device connected to an external pump and tubes. A histological analysis showed that vascular channels were constructed in the skin-equivalent, which showed a conventional dermal/epidermal morphology, and the endothelial cells formed tight junctions on the vascular channel wall. The barrier function of the skin-equivalent was also confirmed. Cell distribution analysis indicated that the vascular channels supplied nutrition to the skin-equivalent. Moreover, the feasibility of a skin-equivalent containing vascular channels as a model for studying vascular absorption was demonstrated by measuring test molecule permeation from the epidermal layer into the vascular channels. The results suggested that this skin-equivalent can be used for skin-on-a-chip applications including drug development, cosmetics testing, and studying skin biology.


Asunto(s)
Células Endoteliales/fisiología , Dispositivos Laboratorio en un Chip , Perfusión/instrumentación , Piel Artificial , Piel/irrigación sanguínea , Piel/crecimiento & desarrollo , Ingeniería de Tejidos/instrumentación , Células Cultivadas , Células Endoteliales/citología , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Técnicas de Cultivo de Órganos/instrumentación , Integración de Sistemas , Andamios del Tejido
18.
Stoch Environ Res Risk Assess ; 31(5): 1253-1269, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-32025200

RESUMEN

Empirical tsunami fragility curves are developed based on a Bayesian framework by accounting for uncertainty of input tsunami hazard data in a systematic and comprehensive manner. Three fragility modeling approaches, i.e. lognormal method, binomial logistic method, and multinomial logistic method, are considered, and are applied to extensive tsunami damage data for the 2011 Tohoku earthquake. A unique aspect of this study is that uncertainty of tsunami inundation data (i.e. input hazard data in fragility modeling) is quantified by comparing two tsunami inundation/run-up datasets (one by the Ministry of Land, Infrastructure, and Transportation of the Japanese Government and the other by the Tohoku Tsunami Joint Survey group) and is then propagated through Bayesian statistical methods to assess the effects on the tsunami fragility models. The systematic implementation of the data and methods facilitates the quantitative comparison of tsunami fragility models under different assumptions. Such comparison shows that the binomial logistic method with un-binned data is preferred among the considered models; nevertheless, further investigations related to multinomial logistic regression with un-binned data are required. Finally, the developed tsunami fragility functions are integrated with building damage-loss models to investigate the influences of different tsunami fragility curves on tsunami loss estimation. Numerical results indicate that the uncertainty of input tsunami data is not negligible (coefficient of variation of 0.25) and that neglecting the input data uncertainty leads to overestimation of the model uncertainty.

19.
Rinsho Shinkeigaku ; 46(7): 496-500, 2006 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-17061704

RESUMEN

A 53-year-old woman was admitted to our hospital because of dropped head. Neurological examination showed no abnormality except for weakness of the neck extensor muscles. Her symptoms worsened in the evening, requiring her to support her head by placing her hand against her chin. Edrophonium and repetitive stimulation tests gave negative results, and anti-acetylcholine receptor antibodies were not detected. She had no thymoma. However, she was found to have a high serum titer of anti-MuSK antibody (37.3 nM). She was diagnosed as having myasthenia gravis (MG) and treatment with pyridostigmine was started. However, this had to be withdrawn because of fasciculation as an adverse effect. She was therefore treated with prednisolone, and this resulted in marked improvement. The initial presenting symptom in this case was dropped head, and there were none of the results of laboratory or electrophysiological examinations that are usually typical of MG. MG was eventually diagnosed by measurement of anti-MuSK antibody. The present case suggests that a patient presenting with dropped head without any obvious cause needs to be studied for the presence of anti-MuSK antibody.


Asunto(s)
Autoanticuerpos/sangre , Miastenia Gravis/inmunología , Miastenia Gravis/fisiopatología , Músculos del Cuello/fisiopatología , Proteínas Tirosina Quinasas/inmunología , Femenino , Humanos , Persona de Mediana Edad , Músculos/enzimología , Miastenia Gravis/diagnóstico
20.
J Biosci Bioeng ; 122(6): 753-757, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27323931

RESUMEN

Vessel-like channels fabricated by embedding sacrificial structures in three-dimensional (3D) cellular constructs and then removing the sacrificial structures have been proposed as a means of providing nutrition to the cells. Alginate gel fibers have been used in the design of such channels owing to their flexibility. However, these channels are closed during culture due to extensive shrinkage of the hydrogel structures when they contain certain cell types such as fibroblasts. Here, we describe a method for fabricating vessel-like channels supported by semi-permeable poly-l-lysine-alginate membrane tubes (PLL-tubes) in a collagen gel. PLL-coated alginate gel fibers were embedded in collagen gel and the inner alginate gel was removed. We were able to form channels in various designs-including branched structures-owing to the flexibility of the alginate gel fibers. Moreover, channels supported by PLL-tubes remained open without shrinkage of the collagen gel containing fibroblasts. These results demonstrate that 3D cellular constructs can be fabricated for culturing cells that would normally induce shrinkage of hydrogel structures.


Asunto(s)
Alginatos/química , Materiales Biomiméticos/química , Vasos Sanguíneos , Nanotubos/química , Polilisina/análogos & derivados , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Células Cultivadas , Colágeno/química , Dermis/citología , Fibroblastos/citología , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polilisina/química
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