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1.
Water Res ; 260: 121919, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38901313

ABSTRACT

Owing to the persistence and increasingly stringent regulations of perfluoroalkyl substances (PFAS), it is necessary to improve their adsorption capacities using activated carbon (AC). However, their adsorption capacities are suppressed by dissolved organic matter (DOM). In this study, two ACs modified with organic silicon (C-OS) and inorganic silicon (C-IS) were synthesized and used for the adsorption of PFAS in raw water (RW). The results showed that the PFAS adsorption capacity of C-IS was much less influenced by DOM than that of the original AC (C-virgin). In RW, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) adsorption capacities on C-IS were 15.08 and 3.65 times higher than those on C-virgin, respectively. DOM had less influence on the PFOA and PFOS adsorption kinetics of C-IS than C-OS and C-virgin. Under multi-PFAS condition, C-IS also exhibited slower desorption of short-chain PFAS and breakthrough in batch and column tests, respectively. Characterization of the ACs before and after adsorption and independent gradient modelling indicated that hydrogen bond interactions between the O-Si of C-IS and the -COOH or -CSO3H groups of PFAS contributed to PFAS adsorption. Density functional theory calculations demonstrated that the adsorption energy of C-IS was much lower than that of C-OS and C-virgin. The arrangement of PFAS molecules on C-OS was chaotic owing to the hydrophobic siloxane chain, whereas the arrangement of PFAS on C-IS was orderly in multi-layer or semi-micelle status and more favorable to PFAS adsorption. This study provides a new strategy for avoiding adverse effects of DOM on PFAS adsorption.

2.
Front Artif Intell ; 7: 1331853, 2024.
Article in English | MEDLINE | ID: mdl-38487743

ABSTRACT

The application of artificial intelligence technology in the medical field has become increasingly prevalent, yet there remains significant room for exploration in its deep implementation. Within the field of orthopedics, which integrates closely with AI due to its extensive data requirements, rotator cuff injuries are a commonly encountered condition in joint motion. One of the most severe complications following rotator cuff repair surgery is the recurrence of tears, which has a significant impact on both patients and healthcare professionals. To address this issue, we utilized the innovative EV-GCN algorithm to train a predictive model. We collected medical records of 1,631 patients who underwent rotator cuff repair surgery at a single center over a span of 5 years. In the end, our model successfully predicted postoperative re-tear before the surgery using 62 preoperative variables with an accuracy of 96.93%, and achieved an accuracy of 79.55% on an independent external dataset of 518 cases from other centers. This model outperforms human doctors in predicting outcomes with high accuracy. Through this methodology and research, our aim is to utilize preoperative prediction models to assist in making informed medical decisions during and after surgery, leading to improved treatment effectiveness. This research method and strategy can be applied to other medical fields, and the research findings can assist in making healthcare decisions.

3.
Nat Commun ; 15(1): 619, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38242904

ABSTRACT

The neural signals produced by varying electrical stimulation parameters lead to characteristic neural circuit responses. However, the characteristics of neural circuits reconstructed by electrical signals remain poorly understood, which greatly limits the application of such electrical neuromodulation techniques for the treatment of spinal cord injury. Here, we develop a dual electrical stimulation system that combines epidural electrical and muscle stimulation to mimic feedforward and feedback electrical signals in spinal sensorimotor circuits. We demonstrate that a stimulus frequency of 10-20 Hz under dual stimulation conditions is required for structural and functional reconstruction of spinal sensorimotor circuits, which not only activates genes associated with axonal regeneration of motoneurons, but also improves the excitability of spinal neurons. Overall, the results provide insights into neural signal decoding during spinal sensorimotor circuit reconstruction, suggesting that the combination of epidural electrical and muscle stimulation is a promising method for the treatment of spinal cord injury.


Subject(s)
Spinal Cord Injuries , Spinal Cord , Humans , Spinal Cord/physiology , Spinal Cord Injuries/therapy , Motor Neurons , Electric Stimulation
4.
Nat Chem Biol ; 2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37945898

ABSTRACT

After the discovery of insulin, a century ago, extensive work has been done to unravel the molecular network regulating insulin secretion. Here we performed a chemical screen and identified AZD7762, a compound that potentiates glucose-stimulated insulin secretion (GSIS) of a human ß cell line, healthy and type 2 diabetic (T2D) human islets and primary cynomolgus macaque islets. In vivo studies in diabetic mouse models and cynomolgus macaques demonstrated that AZD7762 enhances GSIS and improves glucose tolerance. Furthermore, genetic manipulation confirmed that ablation of CHEK2 in human ß cells results in increased insulin secretion. Consistently, high-fat-diet-fed Chk2-/- mice show elevated insulin secretion and improved glucose clearance. Finally, untargeted metabolic profiling demonstrated the key role of the CHEK2-PP2A-PLK1-G6PD-PPP pathway in insulin secretion. This study successfully identifies a previously unknown insulin secretion regulating pathway that is conserved across rodents, cynomolgus macaques and human ß cells in both healthy and T2D conditions.

5.
Front Bioeng Biotechnol ; 11: 1252816, 2023.
Article in English | MEDLINE | ID: mdl-37731757

ABSTRACT

Osteosarcoma, the most common primary malignant bone tumor, is characterized by malignant cells producing osteoid or immature bone tissue. Most osteosarcoma patients require reconstructive surgery to restore the functional and structural integrity of the injured bone. Metal orthopedic implants are commonly used to restore the limb integrity in postoperative patients. However, conventional metal implants with a bioinert surface cannot inhibit the growth of any remaining cancer cells, resulting in a higher risk of cancer recurrence. Herein, we fabricate a selenium-doped TiO2 nanotube array (Se-doped TNA) film to modify the surface of medical pure titanium substrate, and evaluate the anti-tumor effect and biocompatibility of Se-doped TNA film. Moreover, we further explore the anti-tumor potential mechanism of Se-doped TNA film by studying the behaviors of human osteosarcoma cells in vitro. We provide a new pathway for achieving the anti-tumor function of orthopedic implants while keeping the biocompatibility, aiming to suppress the recurrence of osteosarcoma.

6.
Sci Total Environ ; 900: 165876, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-37517737

ABSTRACT

Water cellars are traditional rainwater harvesting facilities that have been widely used in rural areas of northwest China. However, there are few reports about the water quality and health risk caused by the cellar water, especially phthalate esters (PAEs) and perfluoroalkyl substances (PFASs). This study investigated and assessed the health risks caused by the metals, PAEs, PFASs and bacterial communities in cellar water. The results showed that the turbidity and total number of bacterial colonies ranged from 4.7 to 58.5 NTU and 5-557 CFU/mL, respectively. The turbidity and total number of bacterial colonies were the main water quality problems. Due to high concentration of Tl (0.005-0.171 µg/L), the samples reached a high level of metal pollution. PAEs showed no non-carcinogenic and carcinogenic risk. The perfluorobutanoic acid (PFBA), perfluorobutanesulfonic acid (PFBS), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) were the main components of PFASs. PFOA and PFOS reached a moderate risk level in many cellar water samples. Moreover, Tl, Pb, As, PFBA and PFBS could change the bacterial community composition and induce the enrichment of bacterial functions related to human diseases. Besides these parameters, dissolved oxygen (DO) also affected the bacterial functions related to human diseases. Therefore, more attention should be paid to turbidity, DO, Tl, Pb, As, PFOA, PFOS, PFBA and PFBS in the cellar water. These results are meaningful for the water quality guarantee and health protection in rural areas of China.


Subject(s)
Alkanesulfonic Acids , Fluorocarbons , Water Pollutants, Chemical , Humans , Water Pollutants, Chemical/analysis , Lead , Environmental Monitoring , Alkanesulfonic Acids/analysis , Fluorocarbons/analysis , Water Quality , China , Esters
7.
Biomed Pharmacother ; 160: 114326, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36736279

ABSTRACT

Osteoporosis is a common disease of the elderly that affects millions of patients worldwide. It is mainly characterized by low bone mineral density and increased risk of fracture due to the deterioration of the bone structure, leading to difficulties in functional recovery, reduced quality of life, increased disability risk and mortality in the population. It has already been a major public health problem. Osteoporosis is a chronic disease that is difficult to treat in the elderly population, so it is crucial to develop new drugs for the treatment of osteoporosis. Oleoyl serine, an endogenous fatty acyl amide found in bone, has been shown to have excellent anti-osteoporosis effects, but it is easily hydrolyzed by amidases in vivo. The aim of this study is to determine the anti-osteoporotic effect of calcium-derived oleoyl serine, a novel oleoyl serine derivative and the molecular mechanism underneath. In vitro experiments demonstrated that calcium-derived oleoyl serine suppressed the expression of Fabp4, and Cebpα while Alp, and Runx2 was significantly upregulated compared with the oleoyl serine group and control. With the activation of ß-catenin, calcium-derived oleoyl serine restored the abnormal osteogenesis and lipogenesis, indicating calcium-derived oleoyl serine compared with oleoyl serine has better effects on promoting osteogenesis and suppressing lipogenesis. In vivo experiment agreed with these findings that calcium-derived oleoyl serine promotes osteogenesis and suppresses its lipogenesis to ameliorate osteoporosis via a ß-catenin dependent method. It is a new candidate for treating osteoporosis.


Subject(s)
Calcium , Osteoporosis , Aged , Humans , Calcium/pharmacology , beta Catenin/metabolism , Serine/pharmacology , Serine/therapeutic use , Quality of Life , Osteoporosis/metabolism , Wnt Signaling Pathway , Osteogenesis , Cell Differentiation
8.
ACS Appl Mater Interfaces ; 14(51): 56930-56937, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36516325

ABSTRACT

The utilization of solar light to trigger organic syntheses for the production of value-added chemicals has attracted increasing recent research attention. The integration of plasmonic Au NPs (NPs = nanoparticles) with MOFs would provide a new way for the development of highly efficient photocatalytic systems. In this manuscript, a bottle-around-ship strategy was adopted for the successful synthesis of a core-shell structured Aupvp@MIL-100(Fe) (PVP = polyvinylpyrrolidone) nanocomposite in room temperature. The as-obtained core-shell structured Aupvp@MIL-100(Fe) show improved photocatalytic performance for benzyl alcohol oxidation under visible light, because of the migration of the surface plasmon resonance (SPR) excited hot electrons from plasmonic Au NPs to MIL-100(Fe), resulting in the production of more active O2•- radicals. The removal of the capping agent PVP from Aupvp@MIL-100(Fe) significantly enhanced the photocatalytic performance, because of an improved charge transfer from plasmonic Au NPs to MIL-100(Fe). This study demonstrates an efficient strategy of fabricating superior photocatalytic systems by a rational coupling of plasmonic Au NPs and photocatalytic active MOFs into a core-shell structured nanocomposite.

9.
Acta Biomater ; 152: 86-99, 2022 10 15.
Article in English | MEDLINE | ID: mdl-36041650

ABSTRACT

Hydrogels are widely used in nerve tissue repair and show good histocompatibility. There remain, however, challenges with hydrogels for applications related to neural signal recording, which requires a tissue-like biomechanical property, high optical transmission, and low impedance. Here, we describe a transparent hydrogel that is highly biocompatible and has a low Young's modulus (0.15 MPa). Additionally, it functions well as an implantable electrode, as it conformably adheres to brain tissue, results in minimal inflammation and has a low impedance of 150 Ω at 1 kHz. Its high transmittance, corresponding to 93.35% at a wavelength of 300 nm to 1100 nm, supports its application in two-photon imaging. Consistent with these properties, this flexible multimodal transparent electrophysiological hydrogel (MTEHy) electrode was able to record neuronal Ca2+ activity using miniature two-photon microscopy. It also used to monitor electrocorticogram (ECoG) activity in real time in freely moving mice. Moreover, its compatibility with magnetic resonance imaging (MRI), indicates that MTEHy is a new tool for studying activity in the cerebral cortex. STATEMENT OF SIGNIFICANCE: Future brain science research requires better-performing implantable electrodes to detect neuronal signaling in the brain. In this study, we developed a new hydrogel material, MTEHy-3, that shows high biocompatibility, high optical transmittance (93.35%) and a low Young's modulus (0.15 MPa). Using as high-biocompatible metal-free hydrogel electrode, MTEHy-3 can be implanted for a long time to study the cerebral cortex, and synchronously record the Ca2+ signaling activity of individual neurons and monitor electrocorticogram activity through ionic conduction in freely moving mice. At the same time, non-metallic MTEHy-3 is also suitable for magnetic resonance imaging. Thus MTEHy-3 provides one in situ multimodal tool to detect neuronal signaling with both high spatial resolution and high temporal resolution in the brain.


Subject(s)
Hydrogels , Neuroimaging , Animals , Brain/physiology , Electrodes, Implanted , Electrophysiological Phenomena , Hydrogels/pharmacology , Mice , Neuroimaging/methods
10.
Article in English | MEDLINE | ID: mdl-35783531

ABSTRACT

Objective: To investigate the relationship between expression levels of platelet miRNAs and severe pneumonia (SP) in children. Methods: A randomized controlled trial was conducted in 129 children with SP hospitalized from May 2018 to May 2020. All children joined the study group and were divided into the mild infection group, moderate infection group, and severe infection group according to the diagnostic criteria, 43 cases in each group. Besides, 129 healthy children were selected as the control group. The expression levels of platelet miR-223 and miR-192 were detected by real-time quantitative polymerase chain reaction (qPCR). The prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (FIB) were detected by the Sysmex CA-1500 System (Sysmex Corporation, Japan). The Pearson analysis was conducted to evaluate the correlation between coagulation function and the levels of miR-223 and miR-192. Results: Compared with the control group, miR-223 in the study group was significantly higher and miR-192 was significantly lower (P < 0.05). Compared with the mild infection group, miR-223 was significantly higher and miR-192 was significantly lower in the moderate infection group and severe infection group (P < 0.05). Compared with the control group, PT and APTT were significantly lower and FIB was significantly higher in the study group (P < 0.05). Pearson correlation analysis revealed that miR-223 was positively correlated with PT and APTT (P < 0.05) and negatively correlated with FIB (P < 0.05); miR-192 was negatively correlated with PT and APTT (P < 0.05) and positively correlated with FIB (P < 0.05). Conclusion: miR-223 and miR-192 can reflect coagulation function in children with SP, which can provide a certain reference basis for clinical guidance and treatment and prognosis.

11.
ACS Appl Mater Interfaces ; 14(22): 25093-25103, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35606333

ABSTRACT

Articular cartilage, which exhibits toughness and ultralow friction even under high squeezing pressures, plays an important role in the daily movement of joints. However, joint soft tissue lesions or injuries caused by diseases, trauma, or human functional decline are inevitable. Poly(vinyl alcohol) (PVA) hydrogels, which have a water content and compressive strength similar to those of many tissues and organs, have the potential to replace tough connective tissues, including cartilage. However, currently, PVA hydrogels are not suitable for complex dynamic environments and lack rebound resilience, especially under long-term or multicycle mechanical loads. Inspired by biological tissues that exhibit increased mechanical strength after swelling, we report a tough engineered hydrogel (TEHy) fabricated by swelling and freeze-thaw methods with a high compressive strength (31 MPa), high toughness (1.17 MJ m-3), a low friction coefficient (0.01), and a low energy loss factor (0.22). Notably, the TEHy remained remarkably resilient after 100 000 cycles of contact extrusion and remains intact after being compressed by an automobile with a weight of approximately 1600 kg. The TEHy also exhibited excellent water swelling resistance (volume and weight changes less than 5%). Moreover, skeletal muscle cells were able to readily attach and proliferate on the surface of TEHy-6, suggesting its outstanding biocompatibility. Overall, this swelling and freeze-thaw strategy solves the antifatigue and stability problems of PVA hydrogels under large static loads (>10 000 N) and provides an avenue to fabricate engineering hydrogels with strong antifatigue and antiswelling properties and ultralow friction for potential use as biomaterials in tissue engineering.


Subject(s)
Cartilage, Articular , Hydrogels , Biocompatible Materials , Compressive Strength , Humans , Polyvinyl Alcohol , Water
12.
Nat Commun ; 13(1): 1043, 2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35210414

ABSTRACT

Restricted ambient temperature and slow heat replenishment in the phase transition of water molecules severely limit the performance of the evaporation-induced hydrovoltaic generators. Here we demonstrate a heat conduction effect enhanced hydrovoltaic power generator by integrating a flexible ionic thermoelectric gelatin material with a porous dual-size Al2O3 hydrovoltaic generator. In the hybrid heat conduction effect enhanced hydrovoltaic power generator, the ionic thermoelectric gelatin material can effectively improve the heat conduction between hydrovoltaic generator and near environment, thus increasing the water evaporation rate to improve the output voltage. Synergistically, hydrovoltaic generator part with continuous water evaporation can induce a constant temperature difference for the thermoelectric generator. Moreover, the system can efficiently achieve solar-to-thermal conversion to raise the temperature difference, accompanied by a stable open circuit voltage of 6.4 V for the hydrovoltaic generator module, the highest value yet.

13.
Soft Matter ; 17(40): 9057-9065, 2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34581395

ABSTRACT

Hydrogel-based soft and stretchable materials with skin/tissue-like mechanical properties provide new avenues for the design and fabrication of wearable sensors. However, synthesizing multifunctional hydrogels that simultaneously possess excellent mechanical, electrical and electromagnetic interference (EMI) shielding effectiveness is still a great challenge. In this work, the freeze-casting method is employed to fabricate a multifunctional hydrogel by filling Fe3O4 clusters into poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT:PSS) and polyvinyl alcohol (PVA) composite aqueous solution. The hydrogel possesses superior electrical and mechanical properties as well as great electromagnetic wave shielding properties. Benefiting from the high stretchability (∼904.5%) and fast sensing performance (response time ∼9 ms and self-recovery time ∼12 ms within the strain range ∼100%), the monitoring of human activities and manipulation of a remote-controlled toy car using the hydrogel-based stretchable strain sensors are successfully demonstrated. In addition, a great EMI shielding effectiveness with more than 46 dB in the frequencies of 8-12.5 GHz can be obtained, which provides an alternative strategy for designing next-generation EMI shielding materials. These results indicate that the multifunctional hydrogels can be used as flexible and stretchable sensing electronics requiring effective EMI shielding.

14.
Dalton Trans ; 50(38): 13201-13215, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34505594

ABSTRACT

The utilization of green and sustainable solar energy via photocatalysis is regarded as a promising strategy to tackle the ever-increasing energy shortage and environmental deterioration. In addition to traditional semiconductor-based photocatalysts, metal-organic frameworks (MOFs), a class of crystalline micro-mesoporous hybrid materials constructed from metal or metal nodes interconnected with multi-dentate organic linkers, are emerging as a new type of photocatalytic material. Post-synthetic modifications (PSM) on MOFs, in which chemical transformations or exchanges are made on pre-synthesized MOF materials, are found to be a powerful strategy for fabricating photoactive MOFs based on already existing MOFs. In this frontier article, different PSM strategies for the development of photoactive MOFs, including coordination on unsaturated metal sites, metalation on open coordinated sites, covalent modifications on ligands, ligand exchange, metal exchange and cavity encapsulation, have been summarized. Our views on the challenges and the direction in developing photocatalytic MOFs by PSM are also addressed. We hope that this frontier article can provide some guidance for rational designing of highly efficient MOF-based photocatalysts via PSM strategies and to stimulate more research interest to be devoted to this promising yet largely unexplored field.

15.
Biomaterials ; 272: 120771, 2021 05.
Article in English | MEDLINE | ID: mdl-33798962

ABSTRACT

Three-dimensional (3D) bioprinting has emerged as a promising approach to fabricate living neural constructs with anatomically accurate complex geometries and spatial distributions of neural stem cells (NSCs) for spinal cord injury (SCI) repair. The NSC-laden 3D bioprinting, however, still faces some big challenges, such as cumbersome printing process, poor cell viability, and minimal cell-material interaction. To address these issues, we have fabricated NSC-laden scaffolds by 3D bioprinting and explore for the first time their application for in vivo SCI repair. In our strategy, we have developed a novel biocompatible bioink consisting of functional chitosan, hyaluronic acid derivatives, and matrigel. This bioink shows fast gelation (within 20 s) and spontaneous covalent crosslinking capability, facilitating convenient one-step bioprinting of spinal cord-like constructs. Thus-fabricated scaffolds maintain high NSC viability (about 95%), and offer a benign microenvironment that facilitates cell-material interactions and neuronal differentiation for optimal formation of neural network. The in vivo experiment has further demonstrated that the bioprinted scaffolds promoted the axon regeneration and decreased glial scar deposition, leading to significant locomotor recovery of the SCI model rats, which may represent a general and versatile strategy for precise engineering of central nervous system and other neural organs/tissues for regenerative medicine application.


Subject(s)
Bioprinting , Spinal Cord Injuries , Animals , Axons , Printing, Three-Dimensional , Rats , Spinal Cord Injuries/therapy , Tissue Engineering , Tissue Scaffolds
16.
Angew Chem Int Ed Engl ; 59(52): 23800-23809, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-32945080

ABSTRACT

A 2D boron nanosheet that exhibits high theoretical capacitance, around four times that of graphene, is a significant supercapacitor electrode. However, its bulk structure with low interlaminar conduction and porosity restricts the charge transfer, ion diffusion, and energy density. Herein, we develop a new 2D hetero-nanosheet made of anisotropic boron-carbon nanosheets (ABCNs) by B-C chemical bonds via gas-phase exfoliation and condensation bottom-up strategy. The ABCNs are constructed into high flexible supercapacitor electrode by microfluidic electrospinning. The ABCN electrode greatly promotes smooth migration and excessive storage of electrolyte ions due to large interlayer conductivity, ionic pathways, and accessible surfaces. The flexible supercapacitor delivers ultrahigh volumetric energy density of 167.05 mWh cm-3 and capacitance of 534.5 F cm-3 . A wearable energy-sensor system is designed to stably monitor physiological signals.

17.
Opt Express ; 28(11): 16003-16011, 2020 May 25.
Article in English | MEDLINE | ID: mdl-32549432

ABSTRACT

Femtosecond pump-probe experiments with a ∼6.4 fs time-resolution were performed to investigate the coherent phonon dynamics in a c-plane sapphire crystal before and after intense 800 nm femtosecond laser irradiation. The intense femtosecond laser induced defect/distortion and even re-crystallization of crystalline structures, which result in the appearance of new peaks and relative intensity change in coherent phonon and Raman spectra. The combination of these two spectra was found to be beneficial to evidence the variation of crystalline structure and further to differentiate the origins of new Raman peaks after irradiation. Further analysis of time-dependent differential absorbance with damped cosine function fitting and Fourier transfer calculation yields the vibrational parameters, including periods, damping times and initial phases, before and after irradiation. With these parameters, the defect-effects on damping time and the mechanism of coherent phonon generation were addressed.

18.
Microsyst Nanoeng ; 6: 84, 2020.
Article in English | MEDLINE | ID: mdl-34567694

ABSTRACT

The memristor has been regarded as a promising candidate for constructing a neuromorphic computing platform that is capable of confronting the bottleneck of the traditional von Neumann architecture. Here, inspired by the working mechanism of the G-protein-linked receptor of biological cells, a novel double-layer memristive device with reduced graphene oxide (rGO) nanosheets covered by chitosan (an ionic conductive polymer) as the channel material is constructed. The protons in chitosan and the functional groups in rGO nanosheets imitate the functions of the ligands and receptors of biological cells, respectively. Smooth changes in the response current depending on the historical applied voltages are observed, offering a promising pathway toward biorealistic synaptic emulation. The memristive behavior is mainly a result of the interaction between protons provided by chitosan and the defects and functional groups in the rGO nanosheets. The channel current is due to the hopping of protons through functional groups and is limited by the traps in the rGO nanosheets. The transition from short-term to long-term potentiation is achieved, and learning-forgetting behaviors of the memristor mimicking those of the human brain are demonstrated. Overall, the bioinspired memristor-type artificial synaptic device shows great potential in neuromorphic networks.

19.
Nat Med ; 25(11): 1739-1747, 2019 11.
Article in English | MEDLINE | ID: mdl-31700183

ABSTRACT

Type 2 diabetes is characterized by insulin resistance and a gradual loss of pancreatic beta cell mass and function1,2. Currently, there are no therapies proven to prevent beta cell loss and some, namely insulin secretagogues, have been linked to accelerated beta cell failure, thereby limiting their use in type 2 diabetes3,4. The adipokine adipsin/complement factor D controls the alternative complement pathway and generation of complement component C3a, which acts to augment beta cell insulin secretion5. In contrast to other insulin secretagogues, we show that chronic replenishment of adipsin in diabetic db/db mice ameliorates hyperglycemia and increases insulin levels while preserving beta cells by blocking dedifferentiation and death. Mechanistically, we find that adipsin/C3a decreases the phosphatase Dusp26; forced expression of Dusp26 in beta cells decreases expression of core beta cell identity genes and sensitizes to cell death. In contrast, pharmacological inhibition of DUSP26 improves hyperglycemia in diabetic mice and protects human islet cells from cell death. Pertaining to human health, we show that higher concentrations of circulating adipsin are associated with a significantly lower risk of developing future diabetes among middle-aged adults after adjusting for body mass index (BMI). Collectively, these data suggest that adipsin/C3a and DUSP26-directed therapies may represent a novel approach to achieve beta cell health to treat and prevent type 2 diabetes.


Subject(s)
Complement C3a/genetics , Complement Factor D/pharmacology , Diabetes Mellitus, Type 2/drug therapy , Dual-Specificity Phosphatases/genetics , Insulin-Secreting Cells/drug effects , Mitogen-Activated Protein Kinase Phosphatases/genetics , Animals , Body Mass Index , Cell Dedifferentiation/drug effects , Complement Factor D/genetics , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/pathology , Glucose/metabolism , Humans , Hyperglycemia/drug therapy , Hyperglycemia/genetics , Hyperglycemia/pathology , Insulin/genetics , Insulin Resistance/genetics , Insulin-Secreting Cells/pathology , Mice , Mice, Inbred NOD
20.
Inorg Chem ; 58(24): 16574-16580, 2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31774657

ABSTRACT

MOF-253 (Al(OH)(dcbpy), dcbpy = 2,2'-bipyridine-5,5'-dicarboxylic acid) obtained via a microwave-assisted synthesis was used for the construction of a supported Ru complex containing dcbpy (MOF-253-Ru(dcbpy)2) by coordinating its open N,N'-chelating sites with Ru(II) in Ru(dcbpy)2Cl2. The as-obtained MOF-253-Ru(dcbpy)2 acts as a bifunctional photocatalyst for simultaneous CO2 reduction to produce formic acid and CO, as well as semidehydrogenation of 1,2,3,4-tetrahydroisoquinoline (THIQ) to obtain 3,4-dihydroisoquinoline (DHIQ). The performance over the surface-supported MOF-253-Ru(dcbpy)2 is superior to that over Ru-doped MOF-253 (Ru-MOF-253) obtained via a mix-and-match strategy, indicating that the use of open coordination sites in the MOFs for direct construction of a surface-supported complex is a superior strategy to obtain an MOF-supported homogeneous complex. This study shows the possibility of using an MOF as a platform for the construction of multifunctional heterogeneous photocatalytic systems. The coupling of photocatalytic CO2 reduction with the highly selective dehydrogenation of organics provides an economical and green strategy in photocatalytic CO2 reduction and production of valuable organics simultaneously.

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