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1.
J Environ Manage ; 297: 113389, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34325366

RESUMEN

Radioactive cesium (137Cs) and strontium (90Sr) contaminants in seawater have been a serious problem since the Fukushima accident in 2011 due to their long-term health risks. For the effective and simultaneous removal of radioactive cesium (137Cs) and strontium (90Sr) from seawater, a Prussian blue (PB)-immobilized alginate aerogel (PB-alginate aerogel) was fabricated and its adsorption performance was evaluated. PB nanoparticles were homogeneously dispersed in the three-dimensional porous alginate aerogel matrix, which enabled facile contact with seawater. The PB-alginate aerogel exhibited Cs+ and Sr2+ adsorption capacities of 19.88 and 20.10 mg/g, respectively, without substantial interference because Cs+ and Sr2+ adsorption occurred at different adsorption sites on the composite. The Cs+ and Sr2+ adsorption onto the PB-alginate aerogel was completed within 3 h due to the highly porous morphology of the aerogel. The Cs+ and Sr2+ adsorption behaviors on the PB-alginate aerogel were systematically investigated under various conditions. Compared with Cs+ adsorption, Sr2+ adsorption onto the PB-alginate aerogel was more strongly influenced by competing cations (Na+, Mg2+, Ca2+, and K+) in seawater. 137Cs and 90Sr removal tests in real seawater demonstrated the practical feasibility of the PB-alginate aerogel as an adsorbent.


Asunto(s)
Alginatos , Estroncio , Adsorción , Cesio , Radioisótopos de Cesio , Ferrocianuros , Agua de Mar
2.
J Environ Manage ; 205: 192-200, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28985598

RESUMEN

Alginate bead is a promising strontium (Sr) adsorbent in seawater, but highly concentrated Na ions caused over-swelling and damaged the hydrogel bead. To improve the mechanical stability of alginate bead, flexible foam-type zeolite-alginate composite was synthesized and Sr adsorption performance was evaluated in seawater; 1-10% zeolite immobilized alginate foams were prepared by freeze-dry technique. Immobilization of zeolite into alginate foam converted macro-pores to meso-pores which lead to more compact structure. It resulted in less swollen composite in seawater medium and exhibited highly improved mechanical stability compared with alginate bead. Besides, Sr adsorption efficiency and selectivity were enhanced by immobilization of zeolite in alginate foam due to the increase of Sr binding sites (zeolite). In particular, Sr selectivity against Na was highly improved. The 10% zeolite-alginate foam exhibited a higher log Kd of 3.3, while the pure alginate foam exhibited 2.7 in the presence of 0.1 M Na. Finally, in the real seawater, the 10% zeolite-alginate foam exhibited 1.5 times higher Sr adsorption efficiency than the pure alginate foam. This result reveals that zeolite-alginate foam composite is appropriate material for Sr removal in seawater due to its swelling resistance as well as improved Sr adsorption performance in complex media.


Asunto(s)
Radioisótopos de Estroncio , Zeolitas , Adsorción , Alginatos , Ácido Glucurónico , Ácidos Hexurónicos , Agua de Mar , Estroncio
3.
Sensors (Basel) ; 17(6)2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28587242

RESUMEN

Due to the recent demand for high-throughput cellular assays, a lot of efforts have been made on miniaturization of cell-based biosensors by preparing cell microarrays. Various microfabrication technologies have been used to generate cell microarrays, where cells of different phenotypes are immobilized either on a flat substrate (positional array) or on particles (solution or suspension array) to achieve multiplexed and high-throughput cell-based biosensing. After introducing the fabrication methods for preparation of the positional and suspension cell microarrays, this review discusses the applications of the cell microarray including toxicology, drug discovery and detection of toxic agents.


Asunto(s)
Técnicas Biosensibles , Descubrimiento de Drogas , Humanos , Microtecnología , Miniaturización , Análisis de Matrices Tisulares
4.
Cancer Immunol Immunother ; 65(1): 61-72, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26613952

RESUMEN

Myeloid-derived suppressor cells (MDSCs) are one of the most important cell types that contribute to negative regulation of immune responses in the tumor microenvironment. Recently, aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1), a novel pleiotropic cytokine, was identified as an antitumor protein that inhibits angiogenesis and induces antitumor responses. However, the effect of AIMP1 on MDSCs in the tumor environment remains unclear. In the present study, we demonstrated that AIMP1 significantly inhibited tumor growth in 4T1 breast cancer-bearing mice and reduced MDSCs population of tumor sites and spleens of tumor-bearing mice. AIMP1 reduced expansion of MDSCs from bone marrow-derived cells in the tumor-conditioned media. AIMP1 also negatively regulated suppressive activities of MDSCs by inhibiting IL-6 and NO production, and Arg-1 expression. Furthermore, treatment of breast cancer-bearing mice with AIMP1 decreased the capacity of MDSCs to suppress T cell proliferation and Treg cell induction. Western blot and inhibition experiments showed that downregulation of MDSCs functions by AIMP1 may result from attenuated activation of STATs, Akt, and ERK. These findings indicate that AIMP1 plays an essential role in negative regulation of suppressive functions of MDSCs. Therefore, it has a significant potential as a therapeutic agent for cancer treatment.


Asunto(s)
Aminoacil-ARNt Sintetasas/inmunología , Presentación de Antígeno/inmunología , Neoplasias de la Mama/inmunología , Células Mieloides/inmunología , Animales , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C
5.
J Immunol ; 193(11): 5453-60, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25362180

RESUMEN

Myeloid-derived suppressor cells (MDSCs) are major immunosuppressive cells that lead to T cell defects in cancer. IL-18 is important in inflammatory and immune responses. IL-18 has been reported to have a dual effect on tumor progression, as it not only stimulates host immune responses, but also exerts procancer effects by inducing immune escape and angiogenesis. In the present study, we investigated the effect of IL-18 on MDSCs and found that IL-18 treatment significantly increased the percentage and the absolute number of monocytic MDSCs (M-MDSCs) via differentiation of CD11b(-) bone marrow progenitor cells. IL-18-induced MDSCs showed enhanced suppression of T cell proliferation and IFN-γ production along with a dramatic increase of M-MDSC suppressive function, including NO production and arginase 1 expression. Although IL-18 decreased the number of granulocytic MDSCs (G-MDSCs) in a concentration-dependent manner, we found that the absolute number of G-MDSCs and their reactive oxygen species production remained unchanged. Additionally, we demonstrated that IL-18-induced M-MDSCs have a more potent suppressive effect on T cell responses with lower IFN-γ production than do G-MDSCs, suggesting that the increased suppressive effect observed in our study resulted from M-MDSCs. Furthermore, in vivo administration of IL-18 significantly increased the accumulation of M-MDSCs in the tumor microenvironment. Taken together, our findings indicate that IL-18 specifically enhances the differentiation and function of M-MDSCs, leading to immunosuppression.


Asunto(s)
Terapia de Inmunosupresión , Interleucina-18/inmunología , Monocitos/inmunología , Células Mieloides/inmunología , Linfocitos T/inmunología , Animales , Arginasa/metabolismo , Antígeno CD11b/metabolismo , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Interferón gamma/metabolismo , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo
6.
J Environ Manage ; 165: 263-270, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26454070

RESUMEN

In this paper, we investigated alginate microspheres as a low-cost adsorbent for strontium (Sr(II)) removal and recovery from seawater. Alginate microspheres have demonstrated a superior adsorption capacity for Sr(II) ions (≈110 mg/g). A Freundlich isotherm model fits well with the Sr(II) adsorption of an alginate microsphere. The mechanism of Sr(II) adsorption is inferred as an ion exchange reaction with Ca(II) ions. The effects of the solution pH and co-existing ions in seawater are also investigated. Except for a pH of 1-2, Sr(II) adsorption capacity is not affected by pH. However, increasing the seawater concentration of metal cations seriously decreases Sr(II) uptake. In particular, highly concentrated (15,000 mg/L) Na(I) ions significantly interfere with Sr(II) adsorption. Sr(II) desorption was performed using 0.1 M HCl and CaCl2. Both regenerants show an excellent desorption efficiency, but the FTIR spectrum reveals that the chemical structure of the microsphere is destroyed after repeated use of HCl. Conversely, CaCl2 successfully desorbed Sr(II) without damage, and the Sr(II) adsorption capacity does not decrease after three repeated uses. The alginate microsphere was also applied to the adsorption of Sr(II) in a real seawater medium. Because of inhibition by co-existing ions, the Sr(II) adsorption capacity was decreased and the adsorption rate was retarded compared with D.I. water. Although the Sr(II) adsorption capacity was decreased, the alginate microsphere still exhibited 17.8 mg/g of Sr(II) uptake in the seawater medium. Considering its excellent Sr(II) uptake in seawater and its reusability, an alginate microsphere is an appropriate cost-effective adsorbent for the removal and recovery of Sr(II) from seawater.


Asunto(s)
Alginatos/química , Microesferas , Agua de Mar/química , Estroncio/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Modelos Teóricos , Estroncio/química , Contaminantes Químicos del Agua/química
7.
J Immunol ; 188(6): 2592-601, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22345647

RESUMEN

Adiponectin (APN) is a crucial regulator for many inflammatory processes, but its effect on Th cell-mediated responses has not been fully understood. Thus, we investigated the immune-modulatory effects of APN on dendritic cells (DCs) controlling Th cell polarization. APN induced maturation and activation of DCs, as demonstrated by the increased expression of MHC class II, costimulatory molecules in both mouse and human DCs, and it significantly enhanced production of proinflammatory cytokines. APN triggered degradation of IκB proteins, nuclear translocation of NF-κB p65 subunit, and phosphorylation of MAPKs in DCs. Pretreatment with a phospholipase C (PLC)γ inhibitor and a JNK inhibitor suppressed IL-12 production and NF-κB binding activity. Additionally, PLCγ inhibitor downregulated phosphorylation of JNK, indicating that PLCγ and JNK may be upstream molecules of NF-κB. Importantly, APN-treated DCs significantly induced both Th1 and Th17 responses in allogeneic CD4(+) T cells. The addition of a neutralizing anti-IL-12 mAb to the cocultures abolished the secretion of IFN-γ, whereas the blockage of IL-23 and IL-1ß suppressed APN-induced IL-17 production. Immunization of mice with OVA-pulsed, APN-treated DCs efficiently led to Ag-specific Th1 and Th17 cell responses. Taken together, these results demonstrated that APN effectively induced activation of DCs through PLCγ/JNK/NF-κB-signaling pathways, leading to enhanced Th1 and Th17 responses.


Asunto(s)
Adiponectina/inmunología , Células Dendríticas/inmunología , Activación de Linfocitos/inmunología , Transducción de Señal/inmunología , Células TH1/citología , Células Th17/citología , Adiponectina/metabolismo , Animales , Western Blotting , Separación Celular , Células Dendríticas/metabolismo , Femenino , Citometría de Flujo , Humanos , Prueba de Cultivo Mixto de Linfocitos , Sistema de Señalización de MAP Quinasas/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Microscopía Confocal , FN-kappa B/inmunología , FN-kappa B/metabolismo , Fosfolipasa C gamma/inmunología , Fosfolipasa C gamma/metabolismo , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Transfección
8.
Sci Rep ; 14(1): 4597, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409464

RESUMEN

Urea is a problematic pollutant in reclaimed water for ultrapure water (UPW) production. The sulfate radical-based advanced oxidation process (SR-AOP) has been recognized as an effective method for urea degradation. However, conventional metal-based catalysts for peroxymonosulfate (PMS) activation are unsuitable for UPW production due to issues related to metal ion leaching. In this study, the use of powdered activated carbon (PAC) was investigated for the removal of urea from reclaimed water. The PAC exhibited a high degree of defects (ID/IG = 1.709) and various surface oxygen functional groups (C-OH, C=O, and C-O), which greatly enhanced its catalytic capability. The PAC significantly facilitated PMS activation in the PMS + PAC system, leading to the complete urea decomposition. The PMS + PAC system demonstrated excellent urea removal efficiency within a wide pH range, except for pH < 3. Among the various anions present, the CO32- and PO43- inhibited urea degradation, while the coexistence of Cl- promoted urea removal. Furthermore, the feasibility test was evaluated using actual reclaimed water. The quenching test revealed that SO4-·, ·OH, and O2-· played crucial roles in the degradation of urea in the PAC-assisted SR-AOP. The oxygen functional groups (C-OH and O-C=O) and defect sites of PAC clearly contributed to PMS activation.

9.
Chemosphere ; 364: 143118, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39154771

RESUMEN

Biochar is considered a promising biosorbent for harmful organic pollutants in aqueous media. However, only a limited number of biochars derived from industrial sludges have been utilized due to their problematic high ash content and heavy metal leaching. In this study, a highly effective biochar was prepared as a superabsorbent for ciprofloxacin (CIP) from chemical manufacturing plant sludge via K2CO3-activated pyrolysis, and its CIP removal behavior was evaluated. Unlike sewage sludge, chemical manufacturing plant sludge contains low SiO2, resulting in an ultra-pure carbon (95.4%) based biochar with almost negligible ash content. As the pyrolysis temperature increased from 400 to 800 °C, the ordered graphitic carbon structure transformed into an amorphous carbon phase, and most oxygen-containing groups disappeared. However, the pore size significantly decreased to ∼4.5 nm due to the corrosive carbon volatilization caused by K2CO3, resulting in an extremely large surface area of 2331.8 m2/g. Based on its large surface area and porous carbon structure, the activated biochar at 800 °C (CAB-800) exhibited an outstanding CIP adsorption capacity of 555.56 mg/g. The CIP adsorption isotherm, kinetic, and thermodynamic studies were systematically investigated. The CIP adsorption on CAB-800 was mainly attributed to π-π interactions and hydrogen bond formation, with electrostatic interactions partially contributing to the adsorption reaction. From pH 2 to 12, CAB-800 showed an excellent CIP adsorption capacity of over 316.7 mg/g, with adsorption favored under acidic conditions. Except for HCO3- and CO32-, the presence of anions and humic acids did not significantly affect CIP adsorption capacity. These results demonstrate that biochar produced from chemical manufacturing industry sludge via K2CO3 activation is a highly feasible material for the removal of CIP from aqueous media.

10.
Brain Tumor Res Treat ; 12(1): 50-57, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38317488

RESUMEN

BACKGROUND: This study aimed to retrospectively assess results of intracranial meningioma surgery with or without intraoperative neuromonitoring (IONM) in a single institution. METHODS: Two cohorts (a historical cohort and a monitoring cohort) were collected for the analysis. Before IONM was introduced, a total of 107 patients underwent intracranial meningioma operation without IONM from January 2000 to December 2008 by one neurosurgeon (historical cohort). After IONM was introduced, a total of 99 patients with intracranial meningioma were operated under IONM between November 2018 and February 2023 by two neurosurgeons (monitoring cohort). A retrospective comparison was made on the complications from meningioma surgery between the two groups. RESULTS: In the monitoring cohort, warning signals of motor evoked potential (MEPs) or somatosensory evoked potential (SSEPs) were alarmed in 10 patients. Two of these 10 patients aborted the operation and eight of these 10 patients with warning signals underwent tumor resection. Of these eight patients, five showed postoperative morbidity. Five of 89 patients without warning signals developed neurological deficits. In the historical cohort, 14 of 107 patients showed postoperative morbidity or mortality. CONCLUSION: Even after successful resection of intracranial meningiomas prior to the advent of IONM, integration of MEPs and SSEPs monitoring yielded valuable insights for surgical teams during operative procedures.

11.
Opt Express ; 21(17): 19943-50, 2013 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-24105540

RESUMEN

Reflection-type terahertz tomography is obtained using time-domain spectroscopy. Due to different velocities of the terahertz ray in free space and inside a sample, the tomographic transverse plane is not obtained by a simple reconstruction using time index. A pre-processing method is proposed to compensate for the different velocities of the terahertz ray for tomographic reconstruction. Maximum intensity projection, averaging, and short-time Fourier transform are proposed as post-processing methods along the depth direction for the terahertz tomography. Log-scale display is also suggested for a better visualization. Some experimental results with the pre- and post-processing are demonstrated.

12.
Cytokine ; 63(2): 179-86, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23697689

RESUMEN

IL-12 and IL-18 are cytokines which are mainly secreted by endothelial cells and monocytes including dendritic cells. The well-known effects of IL-12 and IL-18 in the protection against bacteria and virus infection as well as tumor development are associated with their characteristics in synergistically driving the development of T helper type 1 (Th1) cells and inducing IFN-γ production. In this study, we compared the knockout effects of IL-12 and/or IL-18 genes on phenotypes and functional capabilities of dendritic cells (DCs) including their ability to polarize naive CD4(+) T cells. The expression levels of surface molecules such as MHC II, CD80, CD86 and ICOSL, and endocytic capacity were not significantly differences between DCs of wild type (WT) mice and double knockout (DKO) mice of IL-12p40 and IL-18. Additionally, DCs lacking IL-12p40 and/or IL-18 genes were equivalently efficient in inducing T cell proliferation, compared with the WT-DCs. Interestingly, IL-10 production significantly decreased in DKO-DCs, while production of other inflammation-related cytokines were unaffected in WT-DCs and DKO-DCs. Importantly, IL-12p40(-/-)-DCs and DKO-DCs severely impaired the ability to induce IFN-γ and IL-17 production from CD4(+) T cells. IL-18(-/-)-DCs also moderately decreased IL-17 production and IL-17-expressing CD4(+) T cells when co-cultured with CD4(+) T cells, demonstrating the involvement of IL-18 in driving IL-17 differentiation. Taken together, these results suggest the principal contribution of IL-12p40 in inducing Th1 and Th17 polarization, regardless of similar surface phenotypes of DCs.


Asunto(s)
Células Dendríticas/metabolismo , Subunidad p40 de la Interleucina-12/metabolismo , Interleucina-18/metabolismo , Células TH1/metabolismo , Células Th17/metabolismo , Animales , Diferenciación Celular/inmunología , Polaridad Celular/inmunología , Proliferación Celular , Células Dendríticas/inmunología , Femenino , Antígenos de Histocompatibilidad Clase II/biosíntesis , Interferón gamma/biosíntesis , Interleucina-10/metabolismo , Subunidad p40 de la Interleucina-12/deficiencia , Subunidad p40 de la Interleucina-12/genética , Interleucina-17/biosíntesis , Interleucina-17/metabolismo , Interleucina-18/deficiencia , Interleucina-18/genética , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células TH1/inmunología , Células Th17/inmunología
13.
Adv Mater Technol ; 8(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36818276

RESUMEN

Liver cultures may be used for disease modeling, testing therapies and predicting drug-induced injury. The complexity of the liver cultures has evolved from hepatocyte monocultures to co-cultures with non-parenchymal cells and finally to precision-cut liver slices. The latter culture format retains liver's native biomolecular and cellular complexity and therefore holds considerable promise for in vitro testing. However, liver slices remain functional for ~72 h in vitro and display limited utility for some disease modeling and therapy testing applications that require longer culture times. This paper describes a microfluidic device for longer-term maintenance of functional organotypic liver cultures. Our microfluidic culture system was designed to enable direct injection of liver tissue into a culture chamber through a valve-enabled side port. Liver tissue was embedded in collagen and remained functional for up to 31 days, highlighted by continued production of albumin and urea. These organotypic cultures also expressed several enzymes involved in xenobiotic metabolism. Conversely, matched liver tissue embedded in collagen in a 96-well plate lost its phenotype and function within 3-5 days. The microfluidic organotypic liver cultures described here represent a significant advance in liver cultivation and may be used for future modeling of liver diseases or for individualized liver-directed therapies.

14.
Int J Biol Macromol ; 242(Pt 1): 124840, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37169053

RESUMEN

Metal-organic frameworks (MOFs) containing bioactive metals have the potential to exhibit antimicrobial activity by releasing metal ions or ligands through the cleavage of metal-ligand bonds. Recently, copper-based MOFs (Cu-MOFs) with sustained release capability, porosity, and structural flexibility have shown promising antimicrobial properties. However, for clinical use, the controlled release of Cu2+ over an extended time period is crucial to prevent toxicity. In this study, we developed an alginate-based antimicrobial scaffold and encapsulated MOFs within a dual-crosslinked alginate polymer network. We synthesized Cu-MOFs containing glutarate (Glu) and 4,4'-azopyridine (AZPY) (Cu(AZPY)-MOF) and encapsulated them in an alginate-based hydrogel through a combination of visible light-induced photo and calcium ion-induced chemical crosslinking processes. We confirmed Cu(AZPY)-MOF synthesis using scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, and thermogravimetric analysis. This antimicrobial hydrogel demonstrated excellent antibacterial and antifungal properties against two bacterial strains (MRSA and S. mutans, with >99.9 % antibacterial rate) and one fungal strain (C. albicans, with >78.7 % antifungal rate) as well as negligible cytotoxicity towards mouse embryonic fibroblasts, making it a promising candidate for various tissue engineering applications in biomedical fields.


Asunto(s)
Cobre , Estructuras Metalorgánicas , Animales , Ratones , Cobre/química , Estructuras Metalorgánicas/farmacología , Alginatos/química , Hidrogeles/química , Antifúngicos , Fibroblastos , Antibacterianos/farmacología , Antibacterianos/química , Metales
15.
Polymers (Basel) ; 15(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37050391

RESUMEN

Hydrogels are widely used in stem cell therapy due to their extensive tunability and resemblance to the extracellular matrix (ECM), which has a three-dimensional (3D) structure. These features enable various applications that enhance stem cell maintenance and function. However, fast and simple hydrogel fabrication methods are desirable for stem cells for efficient encapsulation and to reduce adverse effects on the cells. In this study, we present a one-pot double-crosslinked hydrogel consisting of polyethylene glycol (PEG) and collagen, which can be prepared without the multi-step sequential synthesis of each network, by using bio-orthogonal chemistry. To enhance the adipogenic differentiation efficiency of adipose-derived stem cells (ADSCs), we added degradable components within the hydrogel to regulate matrix stiffness through cell-mediated degradation. Bio-orthogonal reactions used for hydrogel gelation allow rapid gel formation for efficient cell encapsulation without toxic by-products. Furthermore, the hybrid network of synthetic (PEG) and natural (collagen) components demonstrated adequate mechanical strength and higher cell adhesiveness. Therefore, ADSCs grown within this hybrid hydrogel proliferated and functioned better than those grown in the single-crosslinked hydrogel. The degradable elements further improved adipogenesis in ADSCs with dynamic changes in modulus during culture and enabled the retrieval of differentiated cells for potential future applications.

16.
Bioact Mater ; 28: 183-195, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37266448

RESUMEN

The ability to maintain functional hepatocytes has important implications for bioartificial liver development, cell-based therapies, drug screening, and tissue engineering. Several approaches can be used to restore hepatocyte function in vitro, including coating a culture substrate with extracellular matrix (ECM), encapsulating cells within biomimetic gels (Collagen- or Matrigel-based), or co-cultivation with other cells. This paper describes the use of bioactive heparin-based core-shell microcapsules to form and cultivate hepatocyte spheroids. These microcapsules are comprised of an aqueous core that facilitates hepatocyte aggregation into spheroids and a heparin hydrogel shell that binds and releases growth factors. We demonstrate that bioactive microcapsules retain and release endogenous signals thus enhancing the function of encapsulated hepatocytes. We also demonstrate that hepatic function may be further enhanced by loading exogenous hepatocyte growth factor (HGF) into microcapsules and inhibiting transforming growth factor (TGF)-ß1 signaling. Overall, bioactive microcapsules described here represent a promising new strategy for the encapsulation and maintenance of primary hepatocytes and will be beneficial for liver tissue engineering, regenerative medicine, and drug testing applications.

17.
Clin Immunol ; 143(3): 256-65, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22472603

RESUMEN

Aminoacyl tRNA synthetase complex-interacting multicomplex protein 1 (AIMP1) is known as a novel cytokine carrying out a variety of biological activities, including angiogenesis and wound repair. In our previous reports AIMP1 was demonstrated to induce TH1 polarization. However, the effects of AIMP1 deficiency in TH1 or TH2 immune disorders remain unclear. In this study, we characterized phenotypes of AIMP1-deficient mice and investigated the role of AIMP1 in TH2-biased airway hyperreactivity. Clinical signs of allergic airway inflammation were assessed in AIMP1-deficient mice and the effects of AIMP1 deficiency on production of TH2 cytokines were evaluated in T cells using AIMP1-specific siRNA. Additionally, the enhanced pause values and histologic analysis were assessed in mice receiving AIMP1-deficient CD4+ T cells with OVA challenge. Clinical signs of spontaneous airway inflammation were noted in AIMP1-deficienct mice. AIMP1-deficient mice showed strongly increased Penh values in response to methacholine without any allergen exposure. Adoptive transfer of AIMP1-deficient CD4+ T cells to OVA-sensitized C57BL/6 mice exacerbated OVA-induced airway inflammation and increased infiltration of inflammatory cells into the lung. Furthermore, lung DCs in AIMP1-deficient mice showed increased expression of surface molecules, and IL-12p40 level in sera significantly decreased in AIMP1-deficient mice compared to that of wild type mice. These results strongly indicate that AIMP1 plays a role in negatively regulating TH2 responses in vivo, and AIMP1 can be employed as a novel therapeutic agent against TH2-biased diseases, particularly asthma.


Asunto(s)
Asma/inmunología , Hiperreactividad Bronquial/inmunología , Citocinas/deficiencia , Células Th2/inmunología , Traslado Adoptivo , Animales , Líquido del Lavado Bronquioalveolar/inmunología , Linfocitos T CD4-Positivos/inmunología , Citocinas/biosíntesis , Citocinas/genética , Citocinas/inmunología , Silenciador del Gen , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos C57BL
18.
Chemosphere ; 301: 134518, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35395257

RESUMEN

Nitrophenols(NPs) are highly toxic compounds that occur in various industrial effluents. Herein, we investigated Cu nanoparticle-loaded cellulose nanofibril (CNF/PEI-Cu) aerogels as a catalyst for degrading 4-nitrophenol (4NP) in the wastewater. Non-noble metal based low-cost catalyst material and easily scalable preparation method make CNF/PEI-Cu aerogel as an appropriate catalyst for practical application in 4NP wastewater treatment. Our strategy to improve the loading amount of homogeneously distributed Cu nanoparticles was to functionalize a CNF aerogel using polyethylene imine (PEI), which can bind Cu2+ ions. Porous CNF aerogels with homogenously distributed 20-40 nm Cu nanoparticles were obtained by adsorbing Cu2+ ions and chemically reducing them to Cu metal. The FTIR, XRD, SEM, XPS and ICP-OES analysis were used to confirm the in-situ formation of Cu nanoparticles. In the presence of the CNF/PEI-Cu aerogels, 4NP was effectively reduced to 4-aminophenol (4AP) without loss of the Cu nanoparticles. The activation energy (Ea) and reaction rate constant (kapp) of the catalytic 4NP reduction reaction by the CNF/PEI2-Cu aerogels were calculated to be Ea = 39.56 kJ mol-1 and kapp = 0.770 min-1, respectively. The Ea is similar or even smaller than the Ea values of the corresponding reactions involving noble-metal catalysts, demonstrating that the CNF/PEI-Cu aerogels developed in the present study have strong potential as practical and economical catalysts.


Asunto(s)
Celulosa , Nanopartículas del Metal , Celulosa/química , Cobre/química , Iones , Nanopartículas del Metal/química , Metales , Nitrofenoles/química , Porosidad
19.
J Tissue Eng ; 13: 20417314221085645, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35422983

RESUMEN

Three-dimensional spheroid culture enhances cell-to-cell interactions among stem cells and promotes the expression of stem cell properties; however, subsequent retrieval and delivery of these cells remain a challenge. We fabricated a thermoresponsive fiber-based microwell scaffold by combining electrospinning and hydrogel micropatterning. The resultant scaffold appeared to facilitate the formation of cellular spheroids of uniform size and enabled the expression of more stem cell-secreting growth factor genes (EGF, IGF-1, FGF1, FGF2, and HGF), pluripotent stem cell-related genes (SOX2 and NANOG), and adult epithelial stem cell-related genes (LGR4, LGR5, and LGR6) than salivary gland stem cells in a monolayer culture (SGSCmonolayer). The spheroids could be retrieved efficiently by decreasing temperature. SGSC-derived spheroid (SGSCspheroid) cells were then implanted into the submandibular glands of mice at 2 weeks after fractionated X-ray irradiation at a dose of 7.5 Gy/day. At 16 weeks post-irradiation, restoration of salivary function was detected only in SGSCspheroid-implanted mice. The production of submandibular acini specific mucin increased in SGSCspheroid-implanted mice, compared with PBS control. More MIST1+ mature acinar cells were preserved in the SGSCspheroid-implanted group than in the PBS control group. Intriguingly, SGSCspheroid-implanted mice exhibited greater amelioration of tissue damage and preservation of KRT7+ terminally differentiated luminal ductal cells than SGSCmonolayer-implanted mice. The SGSCspheroid-implanted mice also showed less DNA damage and apoptotic cell death than the SGSCmonolayer-implanted mice at 2 weeks post-implantation. Additionally, a significant increase in Ki67+AQP5+ proliferative acinar cells was noted only in SGSCspheroid-implanted mice. Our results suggest that a thermoresponsive fiber-based scaffold could be of use to facilitate the production of function-enhanced SGSCspheroid cells and their subsequent retrieval and delivery to damaged salivary glands to alleviate radiation-induced apoptotic cell death and promote salivary gland regeneration.

20.
Bioact Mater ; 15: 1-14, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35386345

RESUMEN

Human pluripotent stem cells (hPSC) hold considerable promise as a source of adult cells for treatment of diseases ranging from diabetes to liver failure. Some of the challenges that limit the clinical/translational impact of hPSCs are high cost and difficulty in scaling-up of existing differentiation protocols. In this paper, we sought to address these challenges through the development of bioactive microcapsules. A co-axial flow focusing microfluidic device was used to encapsulate hPSCs in microcapsules comprised of an aqueous core and a hydrogel shell. Importantly, the shell contained heparin moieties for growth factor (GF) binding and release. The aqueous core enabled rapid aggregation of hPSCs into 3D spheroids while the bioactive hydrogel shell was used to load inductive cues driving pluripotency maintenance and endodermal differentiation. Specifically, we demonstrated that one-time, 1 h long loading of pluripotency signals, fibroblast growth factor (FGF)-2 and transforming growth factor (TGF)-ß1, into bioactive microcapsules was sufficient to induce and maintain pluripotency of hPSCs over the course of 5 days at levels similar to or better than a standard protocol with soluble GFs. Furthermore, stem cell-carrying microcapsules that previously contained pluripotency signals could be reloaded with an endodermal cue, Nodal, resulting in higher levels of endodermal markers compared to stem cells differentiated in a standard protocol. Overall, bioactive heparin-containing core-shell microcapsules decreased GF usage five-fold while improving stem cell phenotype and are well suited for 3D cultivation of hPSCs.

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