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1.
Nat Commun ; 15(1): 3048, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589497

RESUMEN

Flexible pressure sensors can convert mechanical stimuli to electrical signals to interact with the surroundings, mimicking the functionality of the human skins. Piezocapacitive pressure sensors, a class of most widely used devices for artificial skins, however, often suffer from slow response-relaxation speed (tens of milliseconds) and thus fail to detect dynamic stimuli or high-frequency vibrations. Here, we show that the contact-separation behavior of the electrode-dielectric interface is an energy dissipation process that substantially determines the response-relaxation time of the sensors. We thus reduce the response and relaxation time to ~0.04 ms using a bonded microstructured interface that effectively diminishes interfacial friction and energy dissipation. The high response-relaxation speed allows the sensor to detect vibrations over 10 kHz, which enables not only dynamic force detection, but also acoustic applications. This sensor also shows negligible hysteresis to precisely track dynamic stimuli. Our work opens a path that can substantially promote the response-relaxation speed of piezocapacitive pressure sensors into submillisecond range and extend their applications in acoustic range.

2.
Int J Biol Macromol ; 261(Pt 2): 129910, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309395

RESUMEN

Currently, protein-based hydrogels are widely applied in soft materials, tissue engineering and implantable scaffolds owing to their excellent biocompatibility, and degradability. However, most protein-based hydrogels are soft brittle. In this study, a ductile and mechanically enhanced bovine serum albumin (BSA) hydrogel is fabricated by soaking the a 1-(3-dimethylaminopropyl)-3ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) induced BSA hydrogel in (NH4)2SO4 solution. An EDC/NHS coupling reaction induce protein coupling reactions that cause the BSA skeleton to resemble architectural load-bearing walls, protecting the integrity of the hydrogel and preventing collapse. The effects of the BSA and (NH4)2SO4 concentrations on the hydrogel mechanics are evaluated, and the possible strengthening mechanism is discussed. Besides, the highly kosmotropic ions greatly enhance the hydrophobic interaction within BSA gels and dehydration effect and their mechanical properties were significantly enhanced. The various mechanical properties of hydrogels can be regulated over a large window by soaking hydrogels into various ions. And most of them can be washed away, maintaining high biocompatibility of the protein. Importantly, the protein hydrogels prepared by this strategy could also be modified as strain sensors. In a word, this work demonstrates a new, universal method to provide multi-functional, biocompatible, strength enhanced and regulable mechanical pure protein hydrogel, combining the Hofmeister effect with -NH2/-COOH association groups.


Asunto(s)
Hidrogeles , Albúmina Sérica Bovina , Albúmina Sérica Bovina/química , Hidrogeles/química , Ingeniería de Tejidos , Resistencia a la Tracción , Iones
3.
J Ethnopharmacol ; 325: 117836, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38301985

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Psoriasis is an autoimmune disease characterized by dysfunctional T cells and dysregulated immune responses. Smilax glabra Roxb. (SGR) is a formulation used in Traditional Chinese Medicine for the treatment of inflammatory skin disorders, including psoriasis. This study explores the scientific basis for its use by examining the effects of SGR on T cell differentiation and insulin receptor signaling, relevant pathways implicated in the pathophysiology of psoriasis. AIM OF THE STUDY: This study investigates the therapeutic potential of SGR (a Chinese medicine) in psoriasis and its impact on T cell differentiation. MATERIALS AND METHODS: An integrated network pharmacology and bioinformatics approach was employed to elucidate the mechanisms of SGR in regulating T cell differentiation. A psoriasis mouse model was utilized to evaluate the effects of SGR on T cell subsets. Immunohistochemistry and gene expression analyses were conducted to investigate the modulation of insulin receptor signaling pathways by SGR. RESULTS: SGR treatment effectively reset the expression of various T cell subsets in the psoriasis mouse model, suggesting its ability to regulate T cell differentiation and immune function. Furthermore, SGR treatment inhibited insulin receptor signaling and downstream pathways, including PI3K/AKT and ERK, in psoriatic skin lesions. This indicates that SGR may exert its therapeutic effects through modulation of the insulin receptor signaling pathway. CONCLUSIONS: This study provides novel insights into the therapeutic potential of SGR in psoriasis. By modulating T cell differentiation and targeting the insulin receptor signaling pathway, SGR holds promise as a potential treatment option for psoriasis.


Asunto(s)
Dermatitis , Psoriasis , Smilax , Ratones , Animales , Smilax/química , Fosfatidilinositol 3-Quinasas/metabolismo , Receptor de Insulina , Linfocitos T/metabolismo , Piel , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico , Inflamación/patología , Inmunidad , Modelos Animales de Enfermedad , Ratones Endogámicos BALB C
4.
Artículo en Inglés | MEDLINE | ID: mdl-38079369

RESUMEN

Time-series anomaly detection is a critical task with significant impact as it serves a pivotal role in the field of data mining and quality management. Current anomaly detection methods are typically based on reconstruction or forecasting algorithms, as these methods have the capability to learn compressed data representations and model time dependencies. However, most methods rely on learning normal distribution patterns, which can be difficult to achieve in real-world engineering applications. Furthermore, real-world time-series data is highly imbalanced, with a severe lack of representative samples for anomalous data, which can lead to model learning failure. In this article, we propose a novel end-to-end unsupervised framework called the parallel-attention transformer (PAFormer), which discriminates anomalies by modeling both the global characteristics and local patterns of time series. Specifically, we construct parallel-attention (PA), which includes two core modules: the global enhanced representation module (GERM) and the local perception module (LPM). GERM consists of two pattern units and a normalization module, with attention weights that indicate the relationship of each data point to the whole series (global). Due to the rarity of anomalous points, they have strong associations with adjacent data points. LPM is composed of a learnable Laplace kernel function that learns the neighborhood relevancies through the distributional properties of the kernel function (local). We employ the PA to learn the global-local distributional differences for each data point, which enables us to discriminate anomalies. Finally, we propose a two-stage adversarial loss to optimize the model. We conduct experiments on five public benchmark datasets (real-world datasets) and one synthetic dataset. The results show that PAFormer outperforms state-of-the-art baselines.

5.
Nat Commun ; 14(1): 7121, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37963866

RESUMEN

Humans can gently slide a finger on the surface of an object and identify it by capturing both static pressure and high-frequency vibrations. Although modern robots integrated with flexible sensors can precisely detect pressure, shear force, and strain, they still perform insufficiently or require multi-sensors to respond to both static and high-frequency physical stimuli during the interaction. Here, we report a real-time artificial sensory system for high-accuracy texture recognition based on a single iontronic slip-sensor, and propose a criterion-spatiotemporal resolution, to corelate the sensing performance with recognition capability. The sensor can respond to both static and dynamic stimuli (0-400 Hz) with a high spatial resolution of 15 µm in spacing and 6 µm in height, together with a high-frequency resolution of 0.02 Hz at 400 Hz, enabling high-precision discrimination of fine surface features. The sensory system integrated on a prosthetic fingertip can identify 20 different commercial textiles with a 100.0% accuracy at a fixed sliding rate and a 98.9% accuracy at random sliding rates. The sensory system is expected to help achieve subtle tactile sensation for robotics and prosthetics, and further be applied to haptic-based virtual reality and beyond.

6.
J Ethnopharmacol ; 314: 116645, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37196813

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Tetrastigma Hemsleyanum Diels et Gilg (SYQ) is a typical She ethnomedicine that has been used in anti-tumor treatment in Chinese folklore. The polysaccharide of SYQ (SYQ-PA) has been reported to have antioxidant and anti-inflammatory effects, but the effect and mechanism on antitumor is still unclear. AIM OF THE STUDY: To investigate the activity and mechanism of SYQ-PA against breast cancer in vitro and in vivo. MATERIALS AND METHODS: In this study, different stages of MMTV-PYMT mice, which at 4-week-old and 8-week-old representative the transition from hyperplasia to late carcinoma, were used to investigate the potential effect of SYQ-PA of breast cancer development in vivo. The mechanism was explored with IL4/13-induced peritoneal macrophages model. Flow cytometry assay was employed to analysis the change of tumor microenvironment and the macrophages typing. The inhibition of the condition medium from macrophages on breast cancer cells was detected with xCELLigence system detection. The inflammation factors were tested with cytometric bead array. Co-culture system was used to detect the cell migration and invasion. In addition, the underlying mechanism was investigated using RNAseq analysis, Q-PCR and Western blot, and the PPARγ inhibitor was used to verify the mechanism. RESULTS: SYQ-PA significantly attenuated the process of breast primary tumor growth and reduced the infiltration of TAMs accompanied promoting the polarization of M1 phenotype in MMTV-PyMT mice. Then in vitro studies showed that SYQ-PA promoted macrophages polarization form IL4/13 induced M2 toward to the anti-tumor M1 phenotypes, and the conditioned medium (CM) from the induced macrophages inhibited the proliferation of breast cancer cells. At the same time, SYQ-PA treated macrophages inhibited the migration and invasion of 4T1 in the co-culture system. Further results indicated that SYQ-PA suppressed the release of anti-inflammatory factors and promoted the production of inflammatory cytokines which may induce M1 macrophage polarization and inhibit breast cancer cell proliferation. Subsequently, the underlying mechanism analysis based on RNAseq and molecular assays indicated that SYQ-PA inhibited PPARγ expression and regulated downstream NF-κB in macrophages. After treated with PPARγ inhibitor, T0070907, the effect of SYQ-PA was decreased, or even disappeared. As the downstream, the expression of ß-catenin was also inhibited obviously, those above all contribute the process of SYQ-PA induced M1 macrophages polarization. CONCLUSIONS: Collectively, SYQ-PA was observed inhibited breast cancer, at least in part, via PPARγ activation- and ß-catenin-mediated M2 macrophages polarization. These data expound the antitumor effect and mechanism of SYQ-PA, and provide a possible that SYQ-PA can be used as an adjuvant drug for macrophage tumor immunotherapy in breast cancer.


Asunto(s)
Neoplasias , beta Catenina , Femenino , Animales , Ratones , Macrófagos Asociados a Tumores , PPAR gamma/genética , Interleucina-4 , Transducción de Señal , Microambiente Tumoral , Línea Celular Tumoral
7.
ACS Biomater Sci Eng ; 9(11): 6398-6408, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37126763

RESUMEN

Uncontrolled hemorrhage and infection are the main reasons for many trauma-related deaths in both clinic and battlefield. However, most hemostatic materials have various defects and side effects, such as low hemostatic efficiency, poor biocompatibility, weak degradation ability, and lack of antimicrobial properties. Herein, an oxidized cellulose (OC) sponge with antibacterial properties and biosafety was fabricated for hemorrhage control and wound healing. The as-prepared OC sponges were prone to water triggered expansion and superabsorbent capacity, which could facilitate blood component concentration effectively. Importantly, they had significant biodegradability with little irritation to the skin. This hemostat could also reduce the plasma clotting time to 53.54% in vitro and demonstrated less blood loss than commercially available hemostatic agents (GS) in a mouse model of bleeding from liver defects. Furthermore, the biocompatibility antimicrobial properties and possible hemostatic mechanism of the OC sponge were also systematically evaluated. Importantly, the potential wound healing applications have also been demonstrated. Therefore, the materials have broad clinical application prospects.


Asunto(s)
Celulosa Oxidada , Hemostáticos , Ratones , Animales , Celulosa Oxidada/farmacología , Celulosa Oxidada/uso terapéutico , Hemostáticos/farmacología , Hemostáticos/uso terapéutico , Cicatrización de Heridas , Hemorragia/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
8.
Sci Adv ; 9(9): eadf8831, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36867698

RESUMEN

Iontronic pressure sensors are promising in robot haptics because they can achieve high sensing performance using nanoscale electric double layers (EDLs) for capacitive signal output. However, it is challenging to achieve both high sensitivity and high mechanical stability in these devices. Iontronic sensors need microstructures that offer subtly changeable EDL interfaces to boost sensitivity, while the microstructured interfaces are mechanically weak. Here, we embed isolated microstructured ionic gel (IMIG) in a hole array (28 × 28) of elastomeric matrix and cross-link the IMIGs laterally to achieve enhanced interfacial robustness without sacrificing sensitivity. The embedded configuration toughens and strengthens the skin by pinning cracks and by the elastic dissipation of the interhole structures. Furthermore, cross-talk between the sensing elements is suppressed by isolating the ionic materials and by designing a circuit with a compensation algorithm. We have demonstrated that the skin is potentially useful for robotic manipulation tasks and object recognition.

9.
Adipocyte ; 11(1): 379-388, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35916471

RESUMEN

PARP12 is a member of poly-ADP-ribosyl polymerase (PARPs), which has been characterized for its antiviral function. Yet its physiological implication in adipocytes remains unknown. Here, we report a central function of PARP12 in thermogenic adipocytes. We show that PARP12 is highly expressed in brown adipose tissue and is mainly localized to the mitochondria. Knockdown of PARP12 in vitro reduced UCP1 expression. In parallel, the deficiency of PARP12 reduced mitochondrial respiration in adipocytes, while overexpression of PARP12 reversed these effects.


Asunto(s)
Tejido Adiposo Pardo , Termogénesis , Adipocitos/metabolismo , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/metabolismo , Mitocondrias/metabolismo , Termogénesis/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
10.
Mol Metab ; 63: 101531, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35753632

RESUMEN

OBJECTIVE: White adipose tissue (WAT) possesses the remarkable remodeling capacity, and maladaptation of this ability contributes to the development of obesity and associated comorbidities. Calsyntenin-3 (CLSTN3) is a transmembrane protein that promotes synapse development in brain. Even though this gene has been reported to be associated with adipose tissue, its role in the regulation of WAT function is unknown yet. We aim to further assess the expression pattern of CLSTN3 gene in human adipose tissue, and investigate its regulatory impact on WAT function. METHODS: In our study, we observed the expression pattern of Clstn3/CLSTN3 gene in mouse and human WAT. Genetic association study and expression quantitative trait loci analysis were combined to identify the phenotypic effect of CLSTN3 gene variant in humans. This was followed by mouse experiments using adeno-associated virus-mediated human CLSTN3 overexpression in inguinal WAT. We investigated the effect of CLSTN3 on WAT function and overall metabolic homeostasis, as well as the possible underlying molecular mechanism. RESULTS: We observed that CLSTN3 gene was routinely expressed in human WAT and predominantly enriched in adipocyte fraction. Furthermore, we identified that the variant rs7296261 in the CLSTN3 locus was associated with a high risk of obesity, and its risk allele was linked to an increase in CLSTN3 expression in human WAT. Overexpression of CLSTN3 in inguinal WAT of mice resulted in diet-induced local dysfunctional expansion, liver steatosis, and systemic metabolic deficiency. In vivo and ex vivo lipolysis assays demonstrated that CLSTN3 overexpression attenuated catecholamine-stimulated lipolysis. Mechanistically, CLSTN3 could interact with amyloid precursor protein (APP) in WAT and increase APP accumulation in mitochondria, which in turn impaired adipose mitochondrial function and promoted obesity. CONCLUSION: Taken together, we provide the evidence for a novel role of CLSTN3 in modulating WAT function, thereby reinforcing the fact that targeting CLSTN3 may be a potential approach for the treatment of obesity and associated metabolic diseases.


Asunto(s)
Tejido Adiposo Blanco , Proteínas de Unión al Calcio , Proteínas de la Membrana , Obesidad , Adipocitos/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Humanos , Lipólisis/genética , Lipólisis/fisiología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/metabolismo
11.
Nat Commun ; 13(1): 1317, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35273183

RESUMEN

Electronic skins (e-skins) are devices that can respond to mechanical stimuli and enable robots to perceive their surroundings. A great challenge for existing e-skins is that they may easily fail under extreme mechanical conditions due to their multilayered architecture with mechanical mismatch and weak adhesion between the interlayers. Here we report a flexible pressure sensor with tough interfaces enabled by two strategies: quasi-homogeneous composition that ensures mechanical match of interlayers, and interlinked microconed interface that results in a high interfacial toughness of 390 J·m-2. The tough interface endows the sensor with exceptional signal stability determined by performing 100,000 cycles of rubbing, and fixing the sensor on a car tread and driving 2.6 km on an asphalt road. The topological interlinks can be further extended to soft robot-sensor integration, enabling a seamless interface between the sensor and robot for highly stable sensing performance during manipulation tasks under complicated mechanical conditions.

12.
ACS Nano ; 16(3): 4338-4347, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35234457

RESUMEN

Flexible pressure sensors that have high sensitivity, high linearity, and a wide pressure-response range are highly desired in applications of robotic sensation and human health monitoring. The challenge comes from the incompressibility of soft materials and the stiffening of microstructures in the device interfaces that lead to gradually saturated response. Therefore, the signal is nonlinear and pressure-response range is limited. Here, we show an iontronic flexible pressure sensor that can achieve high sensitivity (49.1 kPa-1), linear response (R2 > 0.995) over a broad pressure range (up to 485 kPa) enabled by graded interlocks of an array of hemispheres with fine pillars in the ionic layer. The high linearity comes from the fact that the pillar deformation can compensate for the effect of structural stiffening. The response-relaxation time of the sensor is <5 ms, allowing the device to detect vibration signals with frequencies up to 200 Hz. Our sensor has been used to recognize objects with different weights based on machine learning during the gripper grasping tasks. This work provides a strategy to make flexible pressure sensors that have combined performances of high sensitivity, high linearity, and wide pressure-response range.

13.
Mol Metab ; 58: 101446, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35114418

RESUMEN

OBJECTIVE: Survivin is a member of the inhibitor of apoptosis family. Our previous study showed that survivin expression could be strongly induced by long-term, high-fat diet (HFD) exposure in vivo. It could also be induced by insulin through the PI3K/mTOR signaling pathway in vitro. Therefore, we hypothesized that under certain conditions, survivin expression might be required for adipocyte function. In the current study, we aim to further investigate the regulation of survivin expression in mature adipocytes upon various nutritional stimuli and the role of survivin using adipocyte-specific survivin knockout (SKO) mice. METHODS: SKO mice were obtained by crossing survivinflox/flox mice with Adiponectin-Cre+/- mice. The overall metabolic phenotype was observed under chow diet (CD) and HFD feeding conditions. The thermogenic program of mice was detected upon cold exposure. The inguinal white adipose tissue (iWAT) and brown adipose tissue (BAT) stromal vascular fraction cells were isolated and differentiated into mature adipocytes, and the effects of survivin deletion on mature adipocyte function were detected in vitro. RESULTS: Survivin expression in adipose tissue and adipocytes was regulated by short-term nutritional stress both in vivo and in vitro. The postnatal development of BAT was impaired in SKO mice, which resulted in drastically reduced BAT mass and decreased expression of the thermogenic protein Ucp1 in 24-week-old mice fed with CD. After HFD feeding, the iWAT and BAT mass of SKO mice were significantly decreased, causing ectopic lipid accumulation in the liver, which was associated with insulin resistance and glucose intolerance. Upon cold exposure, the expression of thermogenic genes and proteins was markedly reduced in BAT and iWAT of SKO mice, accompanied by abnormal mitochondrial structure and induced autophagy. Consistently, thermogenic program and mitochondrial oxidative phosphorylation were reduced in survivin-depleted brown and beige adipocytes in vitro. CONCLUSIONS: Our findings showed that survivin could be regulated by nutritional stress in adipocytes and revealed a new role of survivin in maintaining normal BAT mass and positively regulating the thermogenic program and mitochondrial oxidative phosphorylation.


Asunto(s)
Adipocitos Marrones , Tejido Adiposo Pardo , Adipocitos Marrones/metabolismo , Tejido Adiposo Pardo/metabolismo , Animales , Homeostasis , Ratones , Ratones Noqueados , Survivin/metabolismo
14.
J Ethnopharmacol ; 283: 114675, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34571078

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Ischemic stroke is the most common type of stroke, with high mortality, disability and recurrence rate, which brings a heavy burden to individuals, families and the medical system. Therefore, the intervention and treatment of ischemic stroke are of great significance. Chinese herbal medicine is widely used in treating stroke, for example, Dengzhan shengmai (DZSM) capsule. The current systematic review aims to comprehensively evaluate the efficacy and safety of the DZSM capsule in treating ischemic stroke. MATERIALS AND METHODS: Eligible randomized controlled trials (RCTs) were included to evaluate the efficacy and safety of Chinese herbal medicine DZSM capsule in treating ischemic stroke. Eight electronic databases were searched up to January 27, 2021. The risk ratio (RR), standardized mean difference (SMD), or weighted mean difference (WMD) with 95% confidence interval (CI) were used to assess DZSM capsule treatment outcomes. RESULTS: A total of 28 RCTs involving 6683 participants were included in the systematic review and meta-analysis. Compared with conventional therapy group, DZSM capsule plus conventional therapy improved Barthel Index scores (WMD: 8.97, 95%CI: 5.88-12.05) and reduced modified Rankin Scale (WMD: -0.75, 95%CI: -1.02∼ -0.48), reduced neurological functional deficit scores (WMD: -2.81, 95%CI: -4.17∼ -1.44), recurrence rate (RR: 0.57, 95%CI: 0.44-0.73) and mortality (RR: 0.54, 95%CI: 0.31-0.95), improved clinical effect (RR: 1.18, 95%CI: 1.12-1.24) and quality of life (WMD: 21.67, 95%CI: 6.74-36.61), exhibited a beneficial effect on hemorheology such as elevated levels of APTT (SMD: 1.17, 95%CI: 0.87-1.47) and INR (SMD: 1.12, 95%CI: 0.82-1.42), and on lipid metabolism such as levels of TC (SMD: -0.62, 95%CI: -1.04 âˆ¼ -0.20), TG (SMD: -0.72, 95%CI: -1.18∼ -0.26), LDL (SMD: -1.14, 95%CI: -1.57∼ -0.71) and HDL (SMD: 0.93, 95%CI: 0.36-1.50). No trials reported severe adverse events. CONCLUSION: DZSM capsule appears to be safe and effective in clinical applications for ischemic stroke. Based on conventional therapy, adding the DZSM capsule could reduce the mortality, recurrence rate, and neurological functional deficit scores, improve clinical effect and quality of life. In addition, compared with conventional therapy, the addition of the DZSM capsule played a beneficial role in hemorheology and lipid metabolism, which may attribute to the potential mechanism.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Isquemia Encefálica/complicaciones , Disfunción Cognitiva , Humanos , Metabolismo de los Lípidos/efectos de los fármacos
15.
Mol Cell Endocrinol ; 539: 111485, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619292

RESUMEN

Adipogenesis is regulated by a complicated network of transcription factors among which PPARγ and C/EBP family members are the major regulators. During adipogenesis, C/EBPß is induced early and then transactivates PPARγ and C/EBPα, which cooperatively induce genes whose expressions give rise to the mature adipocyte phenotype. Identifying the factors that influence the expression and activity of C/EBPß should provide additional insight into the mechanisms regulating adipogenesis. Here, we demonstrate that depletion of Ajuba in 3T3-L1 cells significantly decreases mRNA and protein levels of PPARγ and C/EBPα and impairs adipocyte differentiation, while overexpression increases expression of these genes and promotes adipocyte differentiation. Moreover, restoration of C/EBPα or PPARγ expression in Ajuba-deficient 3T3-L1 cells improves the impaired lipid accumulation. Mechanistically, Ajuba interacts with C/EBPß and recruits CBP to facilitate the binding of C/EBPß to the promoter of PPARγ and C/EBPα, resulting in increased H3 histone acetylation and target gene expression. Collectively, these data indicate that Ajuba functions as a co-activator of C/EBPß, and may be an important therapeutic target for combating obesity-related diseases.


Asunto(s)
Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Proteínas con Dominio LIM/genética , PPAR gamma/metabolismo , Células 3T3-L1 , Adipogénesis , Animales , Proteína alfa Potenciadora de Unión a CCAAT/genética , Diferenciación Celular , Regulación de la Expresión Génica , Células HEK293 , Humanos , Proteínas con Dominio LIM/metabolismo , Metabolismo de los Lípidos , Ratones , PPAR gamma/genética
16.
Nat Commun ; 12(1): 4731, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34354053

RESUMEN

Electrodermal devices that capture the physiological response of skin are crucial for monitoring vital signals, but they often require convoluted layered designs with either electronic or ionic active materials relying on complicated synthesis procedures, encapsulation, and packaging techniques. Here, we report that the ionic transport in living systems can provide a simple mode of iontronic sensing and bypass the need of artificial ionic materials. A simple skin-electrode mechanosensing structure (SEMS) is constructed, exhibiting high pressure-resolution and spatial-resolution, being capable of feeling touch and detecting weak physiological signals such as fingertip pulse under different skin humidity. Our mechanical analysis reveals the critical role of instability in high-aspect-ratio microstructures on sensing. We further demonstrate pressure mapping with millimeter-spatial-resolution using a fully textile SEMS-based glove. The simplicity and reliability of SEMS hold great promise of diverse healthcare applications, such as pulse detection and recovering the sensory capability in patients with tactile dysfunction.


Asunto(s)
Fenómenos Fisiológicos de la Piel , Tacto/fisiología , Dispositivos Electrónicos Vestibles , Fenómenos Biomecánicos , Simulación por Computador , Electrodos , Diseño de Equipo , Dedos/fisiología , Análisis de Elementos Finitos , Humanos , Mecanorreceptores/fisiología , Presión , Procesamiento de Señales Asistido por Computador , Relación Señal-Ruido , Textiles , Dispositivos Electrónicos Vestibles/estadística & datos numéricos
17.
ACS Nano ; 15(3): 5752-5761, 2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33683874

RESUMEN

Interfacial solar evaporators (ISEs) for seawater desalination have garnered enormous attention in recent decades due to global water scarcity. Despite the progress in the energy conversion efficiency and production rate of ISE, the poor portability of large-area ISE during transportation as well as the clogging of water transport pathways by precipitated salts during operation remain grand challenges for its fielded applications. Here, we designed an ISE with high energy conversion efficiency and shape morphing capability by integrating carbon nanotube (CNT) fillers with a light-responsive shape memory polymer (SMP, cross-linked polycyclooctene (cPCO)). Utilizing the shape memory effect, our ISE can be folded to an origami with 1/9 of its original size to save space for transportation and allow for on-demand unfolding upon sunlight irradiation when deployed in service. In addition, the ISE is equipped with a real-time clogging monitoring function by measuring the capacitance of the electric double layer (EDL) formed at the evaporator/seawater nanointerface. Due to its good energy conversion efficiency, high portability, and clogging monitoring capability, we envisage our ISE as a promising selection in solar evaporation technologies.

18.
Sci Bull (Beijing) ; 66(11): 1091-1100, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36654343

RESUMEN

Electronic skins and flexible pressure sensors are important devices for advanced healthcare and intelligent robotics. Sensitivity is a key parameter of flexible pressure sensors. Whereas introducing surface microstructures in a capacitive-type sensor can significantly improve its sensitivity, the signal becomes nonlinear and the pressure response range gets much narrower, significantly limiting the applications of flexible pressure sensors. Here, we designed a pressure sensor that utilizes a nanoscale iontronic interface of an ionic gel layer and a micropillared electrode, for highly linear capacitance-to-pressure response and high sensitivity over a wide pressure range. The micropillars undergo three stages of deformation upon loading: initial contact (0-6 kPa) and structure buckling (6-12 kPa) that exhibit a low and nonlinear response, as well as a post-buckling stage that has a high signal linearity with high sensitivity (33.16 kPa-1) over a broad pressure range of 12-176 kPa. The high linearity lies in the subtle balance between the structure compression and mechanical matching of the two materials at the gel-electrode interface. Our sensor has been applied in pulse detection, plantar pressure mapping, and grasp task of an artificial limb. This work provides a physical insight in achieving linear response through the design of appropriate microstructures and selection of materials with suitable modulus in flexible pressure sensors, which are potentially useful in intelligent robots and health monitoring.

19.
Nat Commun ; 11(1): 209, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31924813

RESUMEN

Sensitivity is a crucial parameter for flexible pressure sensors and electronic skins. While introducing microstructures (e.g., micro-pyramids) can effectively improve the sensitivity, it in turn leads to a limited pressure-response range due to the poor structural compressibility. Here, we report a strategy of engineering intrafillable microstructures that can significantly boost the sensitivity while simultaneously broadening the pressure responding range. Such intrafillable microstructures feature undercuts and grooves that accommodate deformed surface microstructures, effectively enhancing the structural compressibility and the pressure-response range. The intrafillable iontronic sensor exhibits an unprecedentedly high sensitivity (Smin > 220 kPa-1) over a broad pressure regime (0.08 Pa-360 kPa), and an ultrahigh pressure resolution (18 Pa or 0.0056%) over the full pressure range, together with remarkable mechanical stability. The intrafillable structure is a general design expected to be applied to other types of sensors to achieve a broader pressure-response range and a higher sensitivity.

20.
Front Endocrinol (Lausanne) ; 11: 592154, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33505355

RESUMEN

Mitochondrial iron-sulfur (Fe-S) cluster is an important cofactor for the maturation of Fe-S proteins, which are ubiquitously involved in energy metabolism; however, factors facilitating this process in beige fat have not been established. Here, we identified BolA family member 3 (Bola3), as one of 17 mitochondrial Fe-S cluster assembly genes, was the most significant induced gene in the browning program of white adipose tissue. Using lentiviral-delivered shRNA in vitro, we determined that Bola3 deficiency inhibited thermogenesis activity without affecting lipogenesis in differentiated beige adipocytes. The inhibition effect of Bola3 knockdown might be through impairing mitochondrial homeostasis and lipolysis. This was evidenced by the decreased expression of mitochondria related genes and respiratory chain complexes, attenuated mitochondrial formation, reduced mitochondrial maximal respiration and inhibited isoproterenol-stimulated lipolysis. Furthermore, BOLA3 mRNA levels were higher in human deep neck brown fat than in the paired subcutaneous white fat, and were positively correlated with thermogenesis related genes (UCP1, CIDEA, PRDM16, PPARG, COX7A1, and LIPE) expression in human omental adipose depots. This study demonstrates that Bola3 is associated with adipose tissue oxidative capacity both in mice and human, and it plays an indispensable role in beige adipocyte thermogenesis via maintaining mitochondrial homeostasis and adrenergic signaling-induced lipolysis.


Asunto(s)
Adipocitos Beige/fisiología , Homeostasis , Lipólisis , Mitocondrias/fisiología , Proteínas Mitocondriales/metabolismo , Termogénesis , Adipocitos Beige/citología , Tejido Adiposo Blanco/citología , Tejido Adiposo Blanco/fisiología , Animales , Diferenciación Celular , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Mitocondriales/genética , Transducción de Señal
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