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1.
Int J Mol Sci ; 24(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37834414

RESUMO

It is meaningful to understand the conversion pathways of nitrogen during the hydrothermal liquefaction process of microalgae to reveal the related reaction mechanisms and develop effective methods to prevent N from ending in biocrude, which eventually increases the quality of biocrude. Extending from our previous works that mainly focused on two high-protein (>50 wt%) microalgae (Chlorella sp. and Spirulina sp.), Nannochloropsis sp., which has a high lipid content (>70 wt%), was used as the feedstock for this project using the same methodology. The high lipid content in Na. induced less nitrogen during the oil phase and as a result, reduced the heteroatom content while also improving the quality of biocrude. It is worth noting that another investigation was conducted on the model compounds with different types of amino acids to specify the effects of the types of amino acids in the proteins in microalgae on the N pathway and their distribution in the products (aqueous phase, oil, solid, and gas). It was found that the basic amino acid in microalgae caused the formation of more N-heterocyclic compounds in the biocrude. The mass flow based on the mass balance was demonstrated to further refine the map showing the predicted reaction pathway of nitrogen from the previous version.


Assuntos
Chlorella , Microalgas , Temperatura , Aminoácidos , Microalgas/química , Nitrogênio , Água , Lipídeos , Biocombustíveis , Biomassa
2.
Clin Respir J ; 17(11): 1182-1189, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37706233

RESUMO

About half of osteosarcomas occur near the knee joint, but other sites such as the humerus, upper femur, fibula, spine, and ilium can also occur. However, rib osteosarcoma is rarely reported. Here, we report the case of a 17-year-old female who was found to have a left dorsal mass on physical examination. Computed tomography (CT) revealed bone destruction in the seventh rib, leading to surgery for mass excision. Pathological results suggested chondroblastic osteosarcoma. After surgery, the patient was treated with chemotherapy and is doing well.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Feminino , Humanos , Adolescente , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/tratamento farmacológico , Tomografia Computadorizada por Raios X , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/cirurgia , Costelas/diagnóstico por imagem , Costelas/cirurgia , Costelas/patologia
3.
ACS Appl Mater Interfaces ; 15(27): 32762-32771, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37389863

RESUMO

Spinal cord injury (SCI) treatment requires a nanosystem for drug delivery that can effectively penetrate the blood-spinal cord barrier (BSCB). Herein, we designed poly(2-methacryloyloxyethyl phosphorylgallylcholine) (PMPC)/l-arginine (PMPC/A)-based nanomotors that can release nitric oxide (NO). The nanomotors were loaded with the inducible NO synthase inhibitor 1400W and nerve growth factor (NGF). PMPC with a zwitterionic structure not only provided good biocompatibility for the nanomotors but also facilitated their passage through the BSCB owing to the assistance of a large number of choline transporters on the BSCB. Additionally, the l-arginine loaded on the nanomotors was able to react with reactive oxygen species in the microenvironment of the injured nerve to produce NO, thereby conferring the ability of autonomic movement to the nanomotors, which facilitated the uptake of drugs by cells in damaged areas and penetration in pathological tissues. Moreover, in vivo animal experiments indicated that the PMPC/A/1400W/NGF nanomotors could effectively pass through the BSCB and restore the motion function of a rat SCI model by regulating its internal environment as well as the release of therapeutic drugs. Thus, the drug delivery system based on nanomotor technology offers a promising strategy for treating central nervous system diseases.


Assuntos
Traumatismos da Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Ratos , Nanopartículas/administração & dosagem , Fator de Crescimento Neural/uso terapêutico , Óxido Nítrico Sintase/antagonistas & inibidores , Sistemas de Liberação de Medicamentos
4.
BMC Musculoskelet Disord ; 24(1): 298, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37060044

RESUMO

OBJECTIVE: To evaluate the biomechanical effects of different miniplates on restorative laminoplasty. METHODS: Assembled restorative laminoplasty models were developed based on 3D printed L4 lamina. Based on different internal fixations, the research was divided into H-shaped miniplates (HSMs) group, two-hole miniplates (THMs) group, and L-shaped miniplates (LSMs) group. The static and dynamic compression tests were analyzed to investigate the biomechanical effects of different internal fixations in restorative laminoplasty, until the failure and fracture of miniplates, or the collapse of miniplates. The static compression tests adopted the speed control mode, and the dynamic fatigue compression tests adopted the load control mode. RESULTS: The "door close" and the collapse of lamina occurred in THMs group and LSMs group, and plate break occurred in LSMs group. However, these phenomenon was absent in HSMs group, and only plate crack around a screw and looseness of a screw tail cap were found in HSMs group. The sustainable yield load of HSMs group was greater than that of THMs group and LSMs group (P < 0.05). No significant difference in yielding-displacement was found between HSMs group and LSMs group (P > 0.05), while both were much less than that of THMs (P < 0.05). Moreover, the compressive stiffness and the axial displacement under the same mechanical load were arranged as follows: HSMs group > LSMs group > THMs group (P < 0.05). The results of dynamic compression test revealed that the peak load of HSMs group could reached 873 N and was 95% of the average yield load of the static compression, and was better than that in THMs group and LSMs group (P < 0.05). Besides, according to the fatigue life-peak load diagram, the ultimate load of HSMs group was more than twice that of THMs group or LSMs group. CONCLUSIONS: The mechanical strength of H-shaped miniplates was superior to two-hole miniplates and L-shaped miniplates in maintaining spinal canal enlargement and spinal stability, and was more excellent in fatigue stability and ultimate load.


Assuntos
Laminoplastia , Humanos , Laminoplastia/métodos , Parafusos Ósseos , Placas Ósseas , Coluna Vertebral , Fixação Interna de Fraturas , Fenômenos Biomecânicos
5.
Redox Biol ; 62: 102682, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36963288

RESUMO

Spinal cord ischemia-reperfusion (IR) injury (SCIRI) is a significant secondary injury that causes damage to spinal cord neurons, leading to the impairment of spinal cord sensory and motor functions. Excessive reactive oxygen species (ROS) production is considered one critical mechanism of neuron damage in SCIRI. Nonetheless, the molecular mechanisms underlying the resistance of neurons to ROS remain elusive. Our study revealed that the deletion of Git1 in mice led to poor recovery of spinal cord motor function after SCIRI. Furthermore, we discovered that Git1 has a beneficial effect on neuron resistance to ROS production. Mechanistically, Git1 interacted with PGK1, regulated PGK1 phosphorylation at S203, and affected the intermediate products of glycolysis in neurons. The influence of Git1 on glycolysis regulates the dimerization of Keap1, which leads to changes in Nrf2 ubiquitination and plays a role in resisting ROS. Collectively, we show that Git1 regulates the Keap1/Nrf2 axis to resist ROS in a PGK1-dependent manner and thus is a potential therapeutic target for SCIRI.


Assuntos
Traumatismo por Reperfusão , Isquemia do Cordão Espinal , Animais , Camundongos , Proteínas de Ciclo Celular , Proteínas Ativadoras de GTPase , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Isquemia do Cordão Espinal/complicações , Isquemia do Cordão Espinal/prevenção & controle
6.
J Neurotrauma ; 39(15-16): 1057-1074, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35243913

RESUMO

Traumatic spinal cord injury (TSCI) is a devastating traumatic disease of the central nervous system, which leads to refractory loss of motor and sensory function. So far, there is no effective treatment for TSCI. Recently, however, nano-sized exosomes from various spinal cord cells have shown great prospects in the treatment of various diseases, including TSCI. Microglia are one of the components of the spinal cord microenvironment. Anti-inflammatory microglia (M2) have been shown to inhibit inflammation and promote the functional recovery of spinal cord after TSCI. However, the role micro RNAs (miRNAs) in exosomes derived from M2 microglia in the treatment of TSCI is unclear. In this study, we investigated whether M2 microglial exosomes (M2-Exos) could better promote the functional behavior recovery of mice with TSCI than M0 microglial exosomes (Exos). Compared with Exos, M2-Exos were found to have a better effect in promoting the recovery of functional behavior, promoting axon regeneration and reducing the level of pyroptosis of spinal cord neurons after TSCI. Through a series of experiments, we also confirmed that miR-672-5p is the most critical miRNA associated with M2-Exos, and that its targeting gene is AIM2. M2-Exos rich in miR-672-5p could inhibit the AIM2/ASC/caspase-1 signaling pathway by inhibiting AIM2 activity, so as to inhibit neuronal pyroptosis and finally promote the recovery of functional behavior in mice with TSCI. In conclusion, our study suggests that the application of M2-Exos may be a promising treatment strategy for TSCI.


Assuntos
Exossomos , MicroRNAs , Piroptose , Traumatismos da Medula Espinal , Animais , Anti-Inflamatórios , Axônios/metabolismo , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Exossomos/metabolismo , Camundongos , MicroRNAs/genética , Microglia/metabolismo , Regeneração Nervosa , Neurônios/metabolismo , Transdução de Sinais , Traumatismos da Medula Espinal/metabolismo
7.
Biomater Sci ; 10(3): 781-793, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34988571

RESUMO

Osteoconductive and osteoinductive scaffolds are highly desirable for functional restoration of large bone defects. Here, we report an in situ mineralized poly(lactic-co-glycolic acid)/poly[2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide hydrogel (PLGA/PSBMA) scaffold as a novel high-efficiency carrier for recombinant human bone morphogenetic protein-2 (rhBMP-2) for bone tissue regeneration. By virtue of the oppositely charged structure, the zwitterionic PSBMA component is able to template well-integrated dense mineralization of calcium phosphate throughout the PLGA/PSBMA scaffold. The high affinity between rhBMP-2 and the mineralized matrix, combined with the capability of the zwitterionic hydrogel to sequester and to enable sustained release of ionic proteins, endows the mineralized PLGA/PSBMA scaffolds with high-efficiency sustained release of rhBMP-2 (only 1.7% release within 35 days), thus enabling robust healing of critical-sized (5 mm) nonunion calvarial defects in rats at an ultralow dosage of rhBMP-2 (150 ng per scaffold), at which level successful healing of critical-sized bone defects has never been reported. These findings show that the mineralized PLGA/PSBMA scaffold is promising for bone defect repair.


Assuntos
Hidrogéis , Ácido Poliglicólico , Animais , Proteína Morfogenética Óssea 2 , Regeneração Óssea , Ácido Láctico , Osteogênese , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Proteínas Recombinantes , Alicerces Teciduais , Fator de Crescimento Transformador beta
8.
J Nanobiotechnology ; 20(1): 56, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093078

RESUMO

Subtalar osteoarthritis (STOA) is often secondary to chronic ankle sprains, which seriously affects the quality of life of patients. Due to its etiology and pathogenesis was not studied equivocally yet, there is currently a lack of effective conservative treatments. Although they have been used for tissue repair, platelet-rich plasma-derived exosomes (PRP-Exo) have the disadvantage of low retention and short-lived therapeutic effects. This study aimed to determine whether incorporation of PRP-Exo in thermosensitive hydrogel (Gel) increased their retention in the joint and thereby playing a therapeutic role on STOA due to chronic mechanical instability established by transecting lateral ligaments (anterior talofibular ligament (ATFL)/calcaneal fibular ligament (CFL)). PRP-Exo incorporated Gel (Exo-Gel) system, composed of Poloxamer-407 and 188 mixture-based thermoresponsive hydrogel matrix in an optimal ratio, was determined by its release ability of Exo and rheology of Gel response to different temperature. The biological activity of Exo-Gel was evaluated in vitro, and the therapeutic effect of Exo-Gel on STOA was evaluated in vivo. Exo released from Exo-Gel continuously for 28 days could promote the proliferation and migration of mouse bone mesenchymal stem cells (mBMSCs) and chondrocytes, at the same time enhance the chondrogenic differentiation of mBMSCs, and inhibit inflammation-induced chondrocyte degeneration. In vivo experiments confirmed that Exo-Gel increased the local retention of Exo, inhibited the apoptosis and hypertrophy of chondrocytes, enhanced their proliferation, and potentially played the role in stem cell recruitment to delay the development of STOA. Thus, Delivery of PRP-Exo incorporated in thermosensitive Gel provides a novel approach of cell-free therapy and has therapeutic effect on STOA.


Assuntos
Exossomos , Osteoartrite , Plasma Rico em Plaquetas , Animais , Cartilagem/metabolismo , Exossomos/metabolismo , Humanos , Camundongos , Osteoartrite/metabolismo , Plasma Rico em Plaquetas/metabolismo , Qualidade de Vida
9.
Adv Neural Inf Process Syst ; 35: 38232-38244, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37090087

RESUMO

Training with backpropagation (BP) in standard deep learning consists of two main steps: a forward pass that maps a data point to its prediction, and a backward pass that propagates the error of this prediction back through the network. This process is highly effective when the goal is to minimize a specific objective function. However, it does not allow training on networks with cyclic or backward connections. This is an obstacle to reaching brain-like capabilities, as the highly complex heterarchical structure of the neural connections in the neocortex are potentially fundamental for its effectiveness. In this paper, we show how predictive coding (PC), a theory of information processing in the cortex, can be used to perform inference and learning on arbitrary graph topologies. We experimentally show how this formulation, called PC graphs, can be used to flexibly perform different tasks with the same network by simply stimulating specific neurons. This enables the model to be queried on stimuli with different structures, such as partial images, images with labels, or images without labels. We conclude by investigating how the topology of the graph influences the final performance, and comparing against simple baselines trained with BP.

10.
IEEE Trans Neural Netw Learn Syst ; 33(12): 7210-7222, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34111003

RESUMO

Support vector machine (SVM) is a particularly powerful and flexible supervised learning model that analyzes data for both classification and regression, whose usual algorithm complexity scales polynomially with the dimension of data space and the number of data points. To tackle the big data challenge, a quantum SVM algorithm was proposed, which is claimed to achieve exponential speedup for least squares SVM (LS-SVM). Here, inspired by the quantum SVM algorithm, we present a quantum-inspired classical algorithm for LS-SVM. In our approach, an improved fast sampling technique, namely indirect sampling, is proposed for sampling the kernel matrix and classifying. We first consider the LS-SVM with a linear kernel, and then discuss the generalization of our method to nonlinear kernels. Theoretical analysis shows our algorithm can make classification with arbitrary success probability in logarithmic runtime of both the dimension of data space and the number of data points for low rank, low condition number, and high dimensional data matrix, matching the runtime of the quantum SVM.

11.
Bioact Mater ; 6(4): 1140-1149, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33134607

RESUMO

Blood lead (Pb(II)) removal is very important but challenging. The main difficulty of blood Pb(II) removal currently lies in the fact that blood Pb(II) is mainly complexed with hemoglobin (Hb) inside the red blood cells (RBCs). Traditional blood Pb(II) removers are mostly passive particles that do not have the motion ability, thus the efficiency of the contact between the adsorbent and the Pb(II)-contaminated Hb is relatively low. Herein, a kind of magnetic nanomotor adsorbent with movement ability under alternating magnetic field based on Fe3O4 nanoparticle modified with meso-2, 3-dimercaptosuccinic acid (DMSA) was prepared and a blood Pb(II) removal strategy was further proposed. During the removal process, the nanomotor adsorbent can enter the RBCs, then the contact probability between the nanomotor adsorbent and the Pb(II)-contaminated Hb can be increased by the active movement of nanomotor. Through the strong coordination of functional groups in DMSA, the nanomotor adsorbent can adsorb Pb(II), and finally be separated from blood by permanent magnetic field. The in vivo extracorporeal blood circulation experiment verifies the ability of the adsorbent to remove blood Pb(II) in pig models, which may provide innovative ideas for blood heavy metal removal in the future.

12.
Chem Commun (Camb) ; 53(55): 7804-7807, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28653075

RESUMO

Two extremely rare ß-cyclodextrin (ß-CD) supported metal-organic frameworks (MOFs), CD-MOF-1 and CD-MOF-2, were induced to crystallize for the first time through a template-induced approach. The targeted CD-MOFs were employed to perform controlled drug delivery and cytotoxicity assays that confirmed their favourable biological potential of being used as drug carriers.


Assuntos
Produtos Biológicos/química , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Células Hep G2 , Humanos , Modelos Moleculares , Tamanho da Partícula , Porosidade , Relação Estrutura-Atividade , Propriedades de Superfície , beta-Ciclodextrinas/química
13.
Opt Express ; 24(11): 12336-48, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27410149

RESUMO

Synchronization is of great scientific interest due to the abundant applications in a wide range of systems. We propose an all-optical scheme to achieve the controllable long-distance synchronization of two dissimilar optomechanical systems, which are unidirectionally coupled through a fiber with light. Synchronization, unsynchronization, and the dependence of the synchronization on driving laser strength and intrinsic frequency mismatch are studied based on the numerical simulation. Taking the fiber attenuation into account, we show that two optomechanical resonators can be unidirectionally synchronized over a distance of tens of kilometers. We also analyze the unidirectional synchronization of three optomechanical systems, demonstrating the scalability of our scheme.

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