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1.
Sci Transl Med ; 16(757): eadg0338, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39047116

RESUMEN

Donor organ shortages for transplantation remain a serious global concern, and alternative treatment is in high demand. Fetal cells and tissues have considerable therapeutic potential as, for example, organoid technology that uses human induced pluripotent stem cells (hiPSCs) to generate unlimited human fetal-like cells and tissues. We previously reported the in vivo vascularization of early fetal liver-like hiPSC-derived liver buds (LBs) and subsquent improved survival of recipient mice with subacute liver failure. Here, we show hiPSC-liver organoids (LOs) that recapitulate midgestational fetal liver promote de novo liver generation when grafted onto the surface of host livers in chemical fibrosis models, thereby recovering liver function. We found that fetal liver, a hematopoietic tissue, highly expressed macrophage-recruiting factors and antifibrotic M2 macrophage polarization factors compared with the adult liver, resulting in fibrosis reduction because of CD163+ M2-macrophage polarization. Next, we created midgestational fetal liver-like hiPSC-LOs by fusion of hiPSC-LBs to induce static cell-cell interactions and found that these contained complex structures such as hepatocytes, vasculature, and bile ducts after transplantation. This fusion allowed the generation of a large human tissue suitable for transplantation into immunodeficient rodent models of liver fibrosis. hiPSC-LOs showed superior liver function compared with hiPSC-LBs and improved survival and liver function upon transplantation. In addition, hiPSC-LO transplantation ameliorated chemically induced liver fibrosis, a symptom of liver cirrhosis that leads to organ dysfunction, through immunomodulatory effects, particularly on CD163+ phagocytic M2-macrophage polarization. Together, our results suggest hiPSC-LO transplantation as a promising therapeutic option for liver fibrosis.


Asunto(s)
Inmunomodulación , Células Madre Pluripotentes Inducidas , Cirrosis Hepática , Hígado , Organoides , Humanos , Cirrosis Hepática/patología , Cirrosis Hepática/terapia , Animales , Hígado/patología , Macrófagos , Trasplante de Hígado , Ratones
2.
J Tissue Eng ; 13: 20417314221143484, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36582939

RESUMEN

Morphologically stable scaffold-free elastic cartilage tissue is crucial for treating external ear abnormalities. However, establishing adequate mechanical strength is challenging, owing to the difficulty of achieving chondrogenic differentiation in vitro; thus, cartilage reconstruction is a complex task. Auricular perichondrial chondroprogenitor cells exhibit high proliferation potential and can be obtained with minimal invasion. Therefore, these cells are an ideal resource for elastic cartilage reconstruction. In this study, we aimed to develop a novel in vitro scaffold-free method for elastic cartilage reconstruction, using human auricular perichondrial chondroprogenitor cells. Inducing chondrogenesis by using microscopic spheroids similar to auricular hillocks significantly increased the chondrogenic potential. The size and elasticity of the tissue were maintained after craniofacial transplantation in immunodeficient mice, suggesting that the reconstructed tissue was morphologically stable. Our novel tissue reconstruction method may facilitate the development of future treatments for external ear abnormalities.

3.
Appl Opt ; 61(32): 9716-9736, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36606914

RESUMEN

The Sunrise chromospheric infrared spectropolarimeter (SCIP) installed in the international balloon experiment sunrise iii will perform spectropolarimetric observations in the near-infrared band to measure solar photospheric and chromospheric magnetic fields simultaneously. The main components of SCIP for polarization measurements are a rotating wave plate, polarization beam splitters, and CMOS imaging sensors. In each of the sensors, SCIP records the orthogonal linearly polarized components of light. The polarization is later demodulated on-board. Each sensor covers one of the two distinct wavelength regions centered at 770 and 850 nm. To retrieve the proper circular polarization, the new parameter R, defined as the 45° phase shifted component of Stokes V in the modulation curve, is introduced. SCIP is aimed at achieving high polarization precision (1σ<3×10-4 of continuum intensity) to capture weak polarization signals in the chromosphere. The objectives of the polarization calibration test presented in this paper are to determine a response matrix of SCIP and to measure its repeatability and temperature dependence to achieve the required polarization precision. Tolerances of the response matrix elements were set after considering typical photospheric and chromospheric polarization signal levels. We constructed a feed optical system such that a telecentric beam can enter SCIP with the same f-number as the light distribution instrument of the sunrise iii telescope. A wire-grid linear polarizer and achromatic wave plate were placed before SCIP to produce the known polarization. The obtained response matrix was close to the values expected from the design. The wavelength and spatial variations, repeatability, and temperature dependence of the response matrix were confirmed to be smaller than tolerances.

4.
Int J Mol Sci ; 21(22)2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33187369

RESUMEN

Microtia is a congenital aplasia of the auricular cartilage. Conventionally, autologous costal cartilage grafts are collected and shaped for transplantation. However, in this method, excessive invasion occurs due to limitations in the costal cartilage collection. Due to deformation over time after transplantation of the shaped graft, problems with long-term morphological maintenance exist. Additionally, the lack of elasticity with costal cartilage grafts is worth mentioning, as costal cartilage is a type of hyaline cartilage. Medical plastic materials have been transplanted as alternatives to costal cartilage, but transplant rejection and deformation over time are inevitable. It is imperative to create tissues for transplantation using cells of biological origin. Hence, cartilage tissues were developed using a biodegradable scaffold material. However, such materials suffer from transplant rejection and biodegradation, causing the transplanted cartilage tissue to deform due to a lack of elasticity. To address this problem, we established a method for creating elastic cartilage tissue for transplantation with autologous cells without using scaffold materials. Chondrocyte progenitor cells were collected from perichondrial tissue of the ear cartilage. By using a multilayer culture and a three-dimensional rotating suspension culture vessel system, we succeeded in creating scaffold-free elastic cartilage from cartilage progenitor cells.


Asunto(s)
Cartílago Costal/citología , Cartílago Auricular/citología , Cartílago Elástico/citología , Animales , Células Cultivadas , Condrocitos/citología , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células Madre/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
5.
Orthop Traumatol Surg Res ; 104(8): 1189-1192, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30293749

RESUMEN

INTRODUCTION: A reliable scoring system that predicts the walking ability of hip fracture patients would be useful for clinicians. Here we developed a scoring system for hip fracture patients and evaluated its predictive ability. HYPOTHESIS: We hypothesized that age, sex, presence of dementia, walking ability before the injury, fracture type, serum hemoglobin level, serum albumin level and interval in days between admission and surgery would be the predictive factors of the walking ability at discharge. MATERIAL AND METHODS: Data from 409 patients who underwent hip fracture surgery were included. We analyzed factors that affected walking ability and developed a scoring system that predicts the probability of walking unaided or with a cane at discharge. RESULTS: The mean age of the patients was 81.3 years. A total of 164 (40%) patients could walk unaided or with a cane at discharge. Multivariate logistic regression analysis showed that the obstructive factors for the ability to walk unaided or with a cane at discharge were older age (odds ratio [OR]=0.962, p=0.002), dementia (OR=0.126, p<0.001), use of a cane before injury (OR=0.396, p<0.001), trochanteric fracture (OR=0.571, p=0.027) and low serum albumin level (OR=4.15, p<0.001) at admission. The scoring system used the following formula: Score=5-0.04×age+albumin-2(with dementia)- 1(with use of a cane before injury)-1(with trochanteric fracture). The C-statistics for the scoring system was 0.81 (95% confidence interval, 0.77-0.85). DISCUSSION: This newly developed scoring system of information at admission predicted the discharge mobility of hip fracture patients. In addition to the previously known risk factors, serum albumin level at admission was detected as a new predictor for mobility at discharge. LEVEL OF PROOF: IV, retrospective study.


Asunto(s)
Fracturas de Cadera/fisiopatología , Fracturas de Cadera/cirugía , Limitación de la Movilidad , Caminata , Factores de Edad , Anciano , Anciano de 80 o más Años , Bastones , Demencia/complicaciones , Femenino , Humanos , Masculino , Admisión del Paciente , Alta del Paciente , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Albúmina Sérica/metabolismo
6.
J Orthop Sci ; 23(6): 977-981, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30087014

RESUMEN

BACKGROUND: The use of direct anterior approach (DAA) for hemiarthroplasty in femoral neck fracture patients has recently increased worldwide. However, no previous studies have elucidated or validated risk factors for prolonged operative time in hemiarthroplasty through DAA. Accurately predicting operative time would contribute to and the selection of the most appropriate surgical approach for each patient and the effective use of operating room. METHODS: Data from 151 femoral neck fracture patients who underwent hemiarthroplasty through DAA were evaluated. A multiple linear regression model of the operative time of hemiarthroplasty was developed, including age, sex, body mass index (BMI), surgeons' DAA experience and approach depth (cm) on the axial computed tomography (CT) slice of the hip as independent factors. RESULTS: Mean age at admission was 83.8 [±6.3 standard deviation (SD)] years and mean operative time was 93.1 (±21 SD) min. Operative time increased by 20 min for every 1 cm increase in approach depth [partial regression coefficient (B), 20.4; standardized partial regression coefficient (ß), 0.68; p < 0.001] and increased 13 min when the DAA was performed by a surgeon with DAA experience of <20 cases (B, 13.1; ß, 0.29; p < 0.001). The adjusted R2 of the model was 0.57. CONCLUSIONS: We demonstrated that increased approach depth and surgeons' DAA experience (<20 cases) are novel risk factors for prolonged operative time in femoral neck fracture patients undergoing hemiarthroplasty through DAA. Surgeons should consider these factors when estimating the operative time of surgery and selecting the most appropriate and safe surgical approach for a patient undergoing hemiarthroplasty.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Fracturas del Cuello Femoral/cirugía , Hemiartroplastia/métodos , Tempo Operativo , Anciano , Anciano de 80 o más Años , Femenino , Fracturas del Cuello Femoral/diagnóstico por imagen , Humanos , Modelos Lineales , Masculino , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X
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