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1.
Eur Spine J ; 32(10): 3659-3665, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37249664

RESUMO

PURPOSE: To investigate the effect of postural changes on access for the OLIF of L2 to L5 in patients with degenerative lumbar scoliosis. METHODS: Twenty-one individuals with degenerative lumbar scoliosis were chosen at random, 11 with left-sided convexity and 10 with left-sided concavity. Axial T2-weighted images were used to measure the following variables: (1) the distance between the left psoas major muscle and the abdominal aorta; (2) the angle of the surgical access; (3) the distance between the psoas major muscle attachment point and the vertebral body's transverse axis; (4) the region of the psoas major muscle above the vertebrae; and (5) the width-to-thickness ratio. A statistical analysis of the measured parameters was done. RESULTS: The L2-5 segment in the supine position had a significantly longer window distance in the left convex and left concave groups than in the right lateral recumbent posture (P < 0.05). In all segments, the left concave group outperformed the left convex group, which was substantially higher in the right lateral recumbent posture than in the supine position (P < 0.05). After the position change, the spanning area was significantly higher compared to the same segment in the supine position. The psoas major muscle's morphology was stretched. CONCLUSIONS: The right lateral recumbent position limits access to OLIF for degenerative lumbar scoliosis, and the "safety window" for OLIF operation in the parietal region is smaller in the left convex group compared to the left concave group, posing a higher risk of intraoperative vascular and neurological injury.


Assuntos
Escoliose , Fusão Vertebral , Humanos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Imageamento por Ressonância Magnética/métodos , Espaço Retroperitoneal
2.
Childs Nerv Syst ; 38(10): 2033-2035, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35507081

RESUMO

INTRODUCTION: Diencephalic syndrome (DS) is a rare syndrome with failure to thrive (FTT) as the primary manifestation, which is often associated with astrocytoma or glioma and rarely caused by germinoma. To our knowledge, there are no reports of female patients presenting with DS secondary to germinoma. CASE REPORT: we report a case (an 11-year-old girl) of diencephalic syndrome presenting with FTT. She was diagnosed with severe malnutrition in the local hospital two years before admission and still did not show normal development after long-term nutritional support. Finally, after ruling out increased metabolism, inadequate caloric intake, and nutrient absorption, intracranial MRI showed a space-occupying lesion in the suprasellar cisterna-hypothalamus area. After excluding other causes of FTT, a biopsy was performed for pathological examination and demonstrated a germinoma. An excellent therapeutic effect was achieved during the three-month follow-up after radiotherapy. CONCLUSION: This case reminds us that intracranial tumors should be considered an indispensable etiology for patients with suspicious FTT, and early diagnosis and intervention may achieve a good prognosis.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Germinoma , Doenças da Hipófise , Astrocitoma/cirurgia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Criança , Insuficiência de Crescimento/complicações , Feminino , Germinoma/complicações , Germinoma/diagnóstico por imagem , Germinoma/patologia , Humanos , Síndrome
3.
Photosynth Res ; 147(2): 145-160, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33389443

RESUMO

Process-based coupled model of stomatal conductance-photosynthesis-transpiration was developed to estimate simultaneously stomatal conductance gsw, photosynthetic rate Pn, and transpiration rate Tr during leaf ontogeny. The modified Jarvis model was constructed by superposing the influence of leaf age LA on gsw in traditional Jarvis model. And the modified Farquhar model was constructed by incorporating the relationships of the LA with parameters in Farquhar model into traditional Farquhar model. The average and leaf-age-based coupled models were constructed, respectively, by combining traditional Farquhar and Penman-Monteith models with traditional Jarvis, and combining modified Farquhar and Penman-Monteith models with modified Jarvis. The results showed that the gsw, the maximum rate of carboxylation, maximum rate of electron transport, rate of triose phosphates utilization, and mitochondrial respiration rate varied in a positive skew pattern, while the mesophyll diffusion conductance decreased linearly with increase in LA. The average coupled model underestimated gsw, Pn, and Tr for young leaves and overestimated gsw, Pn, and Tr for old leaves. And the leaf-age-based coupled model generally perfected well in estimating gsw, Pn, and Tr for all leaves during leaf ontogeny. The study will provide basic information for either modeling leaf gsw, Pn, and Tr continuously, or upscaling them from leaf to canopy scale by considering the variation of LA within canopy.


Assuntos
Oryza/fisiologia , Fotossíntese , Transpiração Vegetal , Difusão , Transporte de Elétrons , Células do Mesofilo/fisiologia , Modelos Biológicos , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Água/metabolismo
4.
J Mater Sci Mater Med ; 32(4): 31, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33751254

RESUMO

No effective treatment has been established for nerve dysfunction caused by spinal cord injury (SCI). Orderly axonal growth at the site of spinal cord transection and creation of an appropriate biological microenvironment are important for functional recovery. To axially guiding axonal growth, designing a collagen/silk fibroin scaffold fabricated with 3D printing technology (3D-C/SF) emulated the corticospinal tract. The normal collagen/silk fibroin scaffold with freeze-drying technology (C/SF) or 3D-C/SF scaffold were implanted into rats with completely transected SCI to evaluate its effect on nerve repair during an 8-week observation period. Electrophysiological analysis and locomotor performance showed that the 3D-C/SF implants contributed to significant improvements in the neurogolical function of rats compared to C/SF group. By magnetic resonance imaging, 3D-C/SF implants promoted a striking degree of axonal regeneration and connection between the proximal and distal SCI sites. Compared with C/SF group, rats with 3D-C/SF scaffold exhibited fewer lesions and disordered structures in histological analysis and more GAP43-positive profiles at the lesion site. The above results indicated that the corticospinal tract structure of 3D printing collagen/silk fibroin scaffold improved axonal regeneration and promoted orderly connections within the neural network, which could provided a promising and innovative approach for tissue repair after SCI.


Assuntos
Colágeno/química , Fibroínas/química , Impressão Tridimensional , Traumatismos da Medula Espinal/terapia , Alicerces Teciduais/química , Animais , Axônios/patologia , Varredura Diferencial de Calorimetria , Força Compressiva , Eletrofisiologia , Feminino , Imageamento por Ressonância Magnética , Movimento , Rede Nervosa , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Difração de Raios X
5.
J Neurochem ; 153(2): 230-251, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31465551

RESUMO

Traumatic brain injury (TBI) is a dominant cause of death and permanent disability worldwide. Although TBI could significantly increase the proliferation of adult neural stem cells in the hippocampus, the survival and maturation of newborn cells is markedly low. Increasing evidence suggests that the secretome derived from mesenchymal stem cells (MSCs) would be an ideal alternative to MSC transplantation. The successive and microenvironmentally responsive secretion in MSCs may be critical for the functional benefits provided by transplanted MSCs after TBI. Therefore, it is reasonable to hypothesize that the signaling molecules secreted in response to local tissue damage can further facilitate the therapeutic effect of the MSC secretome. To simulate the complex microenvironment in the injured brain well, we used traumatically injured brain tissue extracts to pretreat umbilical cord mesenchymal stem cells (UCMSCs) in vitro and stereotaxically injected the secretome from traumatic injury-preconditioned UCMSCs into the dentate gyrus of the hippocampus in a rat severe TBI model. The results revealed that compared with the normal secretome, the traumatic injury-preconditioned secretome could significantly further promote the differentiation, migration, and maturation of newborn cells in the dentate gyrus and ultimately improve cognitive function after TBI. Cytokine antibody array suggested that the increased benefits of secretome administration were attributable to the newly produced proteins and up-regulated molecules from the MSC secretome preconditioned by a traumatically injured microenvironment. Our study utilized the traumatic injury-preconditioned secretome to amplify neurogenesis and improve cognitive recovery, suggesting this method may be a novel and safer candidate for nerve repair. Cover Image for this issue: doi: 10.1111/jnc.14741.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Meios de Cultivo Condicionados/farmacologia , Hipocampo/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Neurogênese/efeitos dos fármacos , Animais , Cognição/efeitos dos fármacos , Humanos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Cordão Umbilical
6.
Int J Biometeorol ; 64(10): 1699-1708, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32564191

RESUMO

Measured leaf photosynthetic light response (PLR) curves at different positions were fitted by non-rectangular hyperbola (NRH) equation to characterize vertical profile of parameters in NRH equation, namely maximum net photosynthetic rate Pnmax, initial quantum yield of assimilation φ, dark respiration rate Rd, and convexity of the curve k, at both jointing and heading stages within rice canopy. And leaf-position-specific and canopy average NRH equations were constructed respectively based on measured PLR curves at each specific leaf position and all measured PLR curves within rice canopy. The results showed that the Pnmax, φ, and Rd reached the maximum at the top second leaf and then decreased at jointing stage and decreased in downward leaves at heading stage. The k increased with lowering leaf position at both stages. The leaf-position-specific NRH equation performed well in estimating net photosynthetic rate Pn for all leaves at different positions and stages, while the canopy average NRH equation underestimated leaf Pn at upper canopy and overestimated Pn at lower canopy. The top fourth leaf was suitable for estimating photosynthetic parameters at canopy scale, as the Pnmax, φ, Rd, and k of the top fourth leaf were near to these parameters of rice canopy, and the canopy average NRH equation performed well in estimating leaf Pn for the top fourth leaf. The results will provide basic information for upscaling leaf photosynthesis to canopy scale.


Assuntos
Oryza , Fotossíntese , Luz , Folhas de Planta
7.
J Environ Manage ; 271: 111029, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778309

RESUMO

Biochar has been widely applied to paddy fields to improve soil fertility, crop productivity and carbon sequestration, thereby leading to variations in the CO2 exchange between the paddy fields under flooding irrigation and the atmosphere, as indicated by many previous reports. However, few relevant reports have focused on paddy fields under water-saving irrigation. This study conducted a field experiment to investigate the effects of three biochar addition rates (0, 20 and 40 t ha-1) on the CO2 exchange between paddy fields under controlled irrigation (CI, a water-saving irrigation technique) and the atmosphere in the Taihu Lake region of Southeast China. Our results showed that biochar addition increased the paddy field ecosystem respiration (Reco) and the soil respiration rate (Rs) in the CI paddy fields. And biochar application increased the total CO2 emissions and the total soil CO2 emissions, especially at a rate of 40 t ha-1. In contrast, gross primary productivity (GPP) was decreased and the net ecosystem exchange of CO2 (NEE) was increased with biochar addition. However, biochar addition at a rate of 20 t ha-1 significantly increased the total CO2 absorption and the net CO2 absorption of the CI paddy fields (p < 0.05), whereas biochar addition at a rate of 40 t ha-1 had no effect on the total CO2 absorption and decreased the total net CO2 absorption. At the same time, biochar addition significantly increased soil catalase, invertase and urease activities and contributed substantially to the increase in soil invertase activity. In addition, the soil bacterial, fungal and actinomycetal abundances were evidently increased with biochar addition, of which the soil fungal abundance showed the greatest increase. A high correlation was observed between soil catalase and invertase activities and soil microbial abundance. Reco was highly correlated with air and soil temperatures and soil enzyme activity. A significant quadratic polynomial correlation was observed between GPP and leaf area index (p < 0.01). The combination of biochar addition at a rate of 20 t ha-1 and water-saving irrigation has the potential to increase the size of the carbon sink and promote soil enzyme and microbial activities in paddy field ecosystems.


Assuntos
Oryza , Água , Agricultura , Dióxido de Carbono/análise , Carvão Vegetal , China , Ecossistema , Solo
8.
J Mater Sci Mater Med ; 30(11): 123, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31686219

RESUMO

Prognosis and treatment evaluation of spinal cord injury (SCI) are still in the long-term research stage. Prognostic factors for SCI treatment need effective biomarker to assess therapeutic effect. Quantitative diffusion tensor imaging (DTI) may become a potential indicators for assessing SCI repair. However, its correlation with the results of locomotor function recovery and tissue repair has not been carefully studied. The aim of this study was to use quantitative DTI to predict neurological repair of SCI with transplanting collagen/chitosan scaffold binding basic fibroblast growth factor (bFGF). To achieve our research goals, T10 complete transection SCI model was established. Then collagen/chitosan mixture adsorbed with bFGF (CCS/bFGF) were implanted into rats with SCI. At 8 weeks after modeling, implanting CCS/bFGF demonstrated more significant improvements in locomotor function according to Basso-Beattie-Bresnahan (BBB) score, inclined-grid climbing test, and electrophysiological examinations. DTI was carried out to evaluate the repair of axons by diffusion tensor tractgraphy (DTT), fractional anisotropy (FA) and apparent diffusion coefficient (ADC), a numerical measure of relative white matter from the rostral to the caudal. Parallel to locomotor function recovery, the CCS/bFGF group could significantly promote the regeneration of nerve fibers tracts according to DTT, magnetic resonance imaging (MRI), Bielschowsky's silver staining and immunofluorescence staining. Positive correlations between imaging and locomotor function or histology were found at all locations from the rostral to the caudal (P < 0.0001). These results demonstrated that DTI might be used as an effective predictor for evaluating neurological repair after SCI in experimental trails and clinical cases.


Assuntos
Quitosana/uso terapêutico , Colágeno/uso terapêutico , Imagem de Tensor de Difusão , Fator 2 de Crescimento de Fibroblastos/farmacologia , Traumatismos da Medula Espinal/terapia , Animais , Prótese Vascular , Quitosana/química , Colágeno/química , Fator 2 de Crescimento de Fibroblastos/química , Ratos
9.
Sci Total Environ ; 924: 171611, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462013

RESUMO

The study on the water source of plants in alpine mountainous is of great significance to optimize the allocation and management of water resources, and can also provide important reference for ecological restoration and protection. However, the controls of water sources for different plants in alpine mountainous region remain poorly understood. Based on the advantages of stable isotope tracer and Bayesian (MixSIAR) model, the water source of plants in Qilian Mountains was quantitatively analyzed. The results showed that the water sources of plants in Qilian Mountain mainly included two parts: direct source and indirect source. The direct source is soil water, which provides most of the water that plants need. The highest contribution of soil water to shrubs was 80 %, followed by trees (73 %) and herbs (72 %). It is worth mentioning that trees mainly use deeper soil water (below 60 cm), shrubs mainly use surface and intermediate soil water (0-60 cm), and herbs mainly use surface soil water (0-40 cm). What is more noteworthy is that indirect sources, such as precipitation, glacier and snow meltwater, and groundwater, are also water sources that cannot be ignored for plant growth in study area. Shrubs and Herbs use more soil water in the range of 40-60 cm, which leads to the possibility of water competition between these two planting types. Therefore, attention should be paid to this phenomenon in the process of vegetation restoration and water resources management. Especially when planting or restoring artificial plants, it is necessary to consider the water use strategy of the two plants to avoid unnecessary water competition and water waste. This is of great significance for ecological stability and sustainable utilization of water resources in the study region.


Assuntos
Água Subterrânea , Água , Teorema de Bayes , Recursos Hídricos , Plantas , Solo , China
10.
Regen Biomater ; 11: rbae023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559647

RESUMO

Polyetherketoneketone (PEKK), a high-performance thermoplastic special engineering material, maintains bone-like mechanical properties and has received considerable attention in the biomedical field. The 3D printing technique enables the production of porous scaffolds with a honeycomb structure featuring precisely controlled pore size, porosity and interconnectivity, which holds significant potential for applications in tissue engineering. The ideal pore architecture of porous PEKK scaffolds has yet to be elucidated. Porous PEKK scaffolds with five pore sizes P200 (225 ± 9.8 µm), P400 (411 ± 22.1 µm), P600 (596 ± 23.4 µm), P800 (786 ± 24.2 µm) and P1000 (993 ± 26.0 µm) were produced by a 3D printer. Subsequently, the optimum pore size, the P600, for mechanical properties and osteogenesis was selected based on in vitro experiments. To improve the interfacial bioactivity of porous PEKK scaffolds, hydroxyapatite (HAp) crystals were generated via in situ biomimetic mineralization induced by the phase-transited lysozyme coating. Herein, a micro/nanostructured surface showing HAp crystals on PEKK scaffold was developed. In vitro and in vivo experiments confirmed that the porous PEKK-HAp scaffolds exhibited highly interconnected pores and functional surface structures that were favorable for biocompatibility and osteoinductivity, which boosted bone regeneration. Therefore, this work not only demonstrates that the pore structure of the P600 scaffold is suitable for PEKK orthopedic implants but also sheds light on a synergistic approach involving 3D printing and biomimetic mineralization, which has the potential to yield customized 3D PEKK-HAp scaffolds with enhanced osteoinductivity and osteogenesis, offering a promising strategy for bone tissue engineering.

11.
Neural Regen Res ; 19(10): 2157-2174, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38488550

RESUMO

Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties of various bioactive materials, followed by the introduction of applications based on biochemistry and cell molecules, and discuss the emerging role of biomaterials in promoting neural regeneration. Further, we summarize the adaptive biomaterials infused with exosomes produced from stem cells and stem cells themselves for the treatment of traumatic brain injury. Finally, we present the main limitations of biomaterials for the treatment of traumatic brain injury and offer insights into their future potential.

12.
Bioact Mater ; 39: 375-391, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38846528

RESUMO

The reconstruction of neural function and recovery of chronic damage following traumatic brain injury (TBI) remain significant clinical challenges. Exosomes derived from neural stem cells (NSCs) offer various benefits in TBI treatment. Numerous studies confirmed that appropriate preconditioning methods enhanced the targeted efficacy of exosome therapy. Interferon-gamma (IFN-γ) possesses immunomodulatory capabilities and is widely involved in neurological disorders. In this study, IFN-γ was employed for preconditioning NSCs to enhance the efficacy of exosome (IFN-Exo, IE) for TBI. miRNA sequencing revealed the potential of IFN-Exo in promoting neural differentiation and modulating inflammatory responses. Through low-temperature 3D printing, IFN-Exo was combined with collagen/chitosan (3D-CC-IE) to preserve the biological activity of the exosome. The delivery of exosomes via biomaterial scaffolds benefited the retention and therapeutic potential of exosomes, ensuring that they could exert long-term effects at the injury site. The 3D-CC-IE scaffold exhibited excellent biocompatibility and mechanical properties. Subsequently, 3D-CC-IE scaffold significantly improved impaired motor and cognitive functions after TBI in rat. Histological results showed that 3D-CC-IE scaffold markedly facilitated the reconstruction of damaged neural tissue and promoted endogenous neurogenesis. Further mechanistic validation suggested that IFN-Exo alleviated neuroinflammation by modulating the MAPK/mTOR signaling pathway. In summary, the results of this study indicated that 3D-CC-IE scaffold engaged in long-term pathophysiological processes, fostering neural function recovery after TBI, offering a promising regenerative therapy avenue.

13.
Chin Med J (Engl) ; 136(13): 1513-1522, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37185590

RESUMO

ABSTRACT: Asthma is characterized by chronic airway inflammation and airway hyper-responsiveness. However, the differences in pathophysiology and phenotypic symptomology make a diagnosis of "asthma" too broad hindering individualized treatment. Four asthmatic inflammatory phenotypes have been identified based on inflammatory cell profiles in sputum: eosinophilic, neutrophilic, paucigranulocytic, and mixed-granulocytic. Paucigranulocytic asthma may be one of the most common phenotypes in stable asthmatic patients, yet it remains much less studied than the other inflammatory phenotypes. Understanding of paucigranulocytic asthma in terms of phenotypic discrimination, distribution, stability, surrogate biomarkers, underlying pathophysiology, clinical characteristics, and current therapies is fragmented, which impedes clinical management of patients. This review brings together existing knowledge and ongoing research about asthma phenotypes, with a focus on paucigranulocytic asthma, in order to present a comprehensive picture that may clarify specific inflammatory phenotypes and thus improve clinical diagnoses and disease management.


Assuntos
Asma , Humanos , Asma/tratamento farmacológico , Inflamação/diagnóstico , Sistema Respiratório , Fenótipo , Biomarcadores , Escarro , Eosinófilos , Neutrófilos
14.
Mol Neurobiol ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37989981

RESUMO

Epilepsy is a progression of development and advancement over time. However, the molecular features of epilepsy were poorly studied from a dynamic developmental perspective. We intend to investigate the key mechanisms in the process of epilepsy by exploring the roles of stage-specifically expressed genes. By using time-course transcriptomic data of epileptic samples, we first analyzed the molecular features of epilepsy in different stages and divided it into progression and remission stages based on their transcriptomic features. 34 stage-specifically expressed genes were then identified by the Tau index and verified in other epileptic datasets. These genes were then enriched for immune-related biological functions. Furthermore, we found that the level of immune infiltration and mechanisms at different stages were different, which may result from different types of immune cells playing leading roles in distinct stages. Our findings indicated an essential role of immune regulation as the potential mechanism of epilepsy development.

15.
ACS Appl Mater Interfaces ; 15(4): 5897-5909, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656061

RESUMO

A hydrogel that fuses long-term biologic integration, multimodal responsiveness, and therapeutic functions has received increasing interest as a wearable and implantable sensor but still faces great challenges as an all-in-one sensor by itself. Multiple bonding with stimuli response in a biocompatible hydrogel lights up the field of soft hydrogel interfaces suitable for both wearable and implantable applications. Given that, we proposed a strategy of combining chemical cross-linking and stimuli-responsive physical interactions to construct a biocompatible multifunctional hydrogel. In this hydrogel system, ureidopyrimidinone/tyramine (Upy/Tyr) difunctionalization of gelatin provides abundant dynamic physical interactions and stable covalent cross-linking; meanwhile, Tyr-doped poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) acts as a conductive filler to establish electrical percolation networks through enzymatic chemical cross-linking. Thus, the hydrogel is characterized with improved conductivity, conformal biointegration features (i.e., high stretchability, rapid self-healing, and excellent tissue adhesion), and multistimuli-responsive conductivity (i.e., temperature and urea). On the basis of these excellent performances, the prepared multifunctional hydrogel enables multimodal wearable sensing integration that can simultaneously track both physicochemical and electrophysiological attributes (i.e., motion, temperature, and urea), providing a more comprehensive monitoring of human health than current wearable monitors. In addition, the electroactive hydrogel here can serve as a bidirectional neural interface for both neural recording and therapeutic electrostimulation, bringing more opportunities for nonsurgical diagnosis and treatment of diseases.


Assuntos
Técnicas Biossensoriais , Terapia por Estimulação Elétrica , Dispositivos Eletrônicos Vestíveis , Humanos , Hidrogéis/química , Movimento (Física) , Condutividade Elétrica
16.
Regen Biomater ; 10: rbac085, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36683754

RESUMO

The restoration of nerve dysfunction after traumatic brain injury (TBI) faces huge challenges due to the limited self-regenerative abilities of nerve tissues. In situ inductive recovery can be achieved utilizing biological scaffolds combined with endogenous human umbilical cord mesenchymal stem cells (HUCMSCs)-derived exosomes (MExos). In this study, brain-derived neurotrophic factor-stimulated HUCMSCs-derived exosomes (BMExos) were composited with collagen/chitosan by 3D printing technology. 3D-printed collagen/chitosan/BMExos (3D-CC-BMExos) scaffolds have excellent mechanical properties and biocompatibility. Subsequently, in vivo experiments showed that 3D-CC-BMExos therapy could improve the recovery of neuromotor function and cognitive function in a TBI model in rats. Consistent with the behavioural recovery, the results of histomorphological tests showed that 3D-CC-BMExos therapy could facilitate the remodelling of neural networks, such as improving the regeneration of nerve fibres, synaptic connections and myelin sheaths, in lesions after TBI.

17.
Stem Cell Res Ther ; 14(1): 198, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553595

RESUMO

Regenerative repair of the brain after traumatic brain injury (TBI) remains an extensive clinical challenge, inspiring intensified interest in therapeutic approaches to explore superior repair strategies. Exosome therapy is another research hotspot following stem cell alternative therapy. Prior research verified that exosomes produced by neural stem cells can participate in the physiological and pathological changes associated with TBI and have potential neuroregulatory and repair functions. In comparison with their parental stem cells, exosomes have superior stability and immune tolerance and lower tumorigenic risk. In addition, they can readily penetrate the blood‒brain barrier, which makes their treatment efficiency superior to that of transplanted stem cells. Exosomes secreted by neural stem cells present a promising strategy for the development of novel regenerative therapies. Their tissue regeneration and immunomodulatory potential have made them encouraging candidates for TBI repair. The present review addresses the challenges, applications and potential mechanisms of neural stem cell exosomes in regenerating damaged brains.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Exossomos , Células-Tronco Neurais , Humanos , Exossomos/patologia , Lesões Encefálicas Traumáticas/terapia , Lesões Encefálicas Traumáticas/patologia , Células-Tronco Neurais/patologia , Encéfalo/patologia
18.
Biosens Bioelectron ; 231: 115288, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37058960

RESUMO

Bacterial cellulose (BC) with its inherent nanofibrils framework is an attractive building block for the fabrication of sustainable bioelectronics, but there still lacks an effective and green strategy to regulate the hydrogen-bonding topological structure of BC to improve its optical transparency and mechanical stretchability. Herein, we report an ultra-fine nanofibril-reinforced composite hydrogel by utilizing gelatin and glycerol as hydrogen-bonding donor/acceptor to mediate the rearrangement of the hydrogen-bonding topological structure of BC. Attributing to the hydrogen-bonding structural transition, the ultra-fine nanofibrils were extracted from the original BC nanofibrils, which reduced the light scattering and endowed the hydrogel with high transparency. Meanwhile, the extracted nanofibrils were connected with gelatin and glycerol to establish an effective energy dissipation network, leading to an increase in stretchability and toughness of hydrogels. The hydrogel also displayed tissue-adhesiveness and long-lasting water-retaining capacity, which acted as bio-electronic skin to stably acquire the electrophysiological signals and external stimuli even after the hydrogel was exposing to air condition for 30 days. Moreover, the transparent hydrogel could also serve as a smart skin dressing for optical identification of bacterial infection and on-demand antibacterial therapy after combined with phenol red and indocyanine green. This work offers a strategy to regulate the hierarchical structure of natural materials for designing skin-like bioelectronics toward green, low cost, and sustainability.


Assuntos
Técnicas Biossensoriais , Nanofibras , Celulose/química , Hidrogéis/química , Gelatina , Glicerol , Nanofibras/química , Hidrogênio
19.
Neuropharmacology ; 237: 109633, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327970

RESUMO

Neuroinflammation plays a vital role in intraventricular hemorrhage (IVH). Excessive neuroinflammation after IVH can activate the inflammasome in the cell and accelerate the occurrence of pyroptosis in cells, produce more inflammatory mediators, increase cell death, and lead to neurological deficits. Previous studies have reported that BRD3308 (BRD), an inhibitor of histone deacetylation by histone deacetylase 3 (HDAC3), suppresses inflammation-induced apoptosis and exhibits anti-inflammatory properties. However, it is unclear how BRD reduces the occurrence of the inflammatory cascade. In this study, we stereotactically punctured the ventricles of male C57BL/6J mice and injected autologous blood via the tail vein to simulate ventricular hemorrhage. Magnetic resonance imaging was used to detect ventricular hemorrhage and enlargement. Our findings demonstrated that BRD treatment significantly improved neurobehavioral performance and decreased neuronal loss, microglial activation, and pyroptosis in the hippocampus after IVH. At the molecular level, this treatment upregulated the expression of peroxisome proliferator-activated receptor γ (PPARγ) and inhibited NLRP3-mediated pyroptosis and inflammatory cytokines. Therefore, we concluded that BRD reduced pyroptosis and neuroinflammation and improve nerve function in part by activating the PPARγ/NLRP3/GSDMD signaling pathway. Our findings suggest a potential preventive role for BRD in IVH.


Assuntos
PPAR gama , Piroptose , Animais , Masculino , Camundongos , Hemorragia Cerebral/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Inflamassomos , Camundongos Endogâmicos C57BL , Microglia , Doenças Neuroinflamatórias , Proteína 3 que Contém Domínio de Pirina da Família NLR
20.
Nanoscale ; 16(1): 474-487, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38086669

RESUMO

Vacancy engineering offers an appealing strategy for modifying the electronic structure of transition metals. Transition metals with abundant sulfur vacancies can significantly contribute to the microwave absorption capabilities of absorbers. In this study, an NixSy@De composite material was synthesized through a straightforward hydrothermal synthesis technique. The effective absorption bandwidth (EAB) of this composite material reached 9.86 GHz at 1.44 mm. A minimum reflection loss (RLmin) of -33.61 dB at 1 mm was achieved, and after mild etching, the RLmin further improved to -93.53 dB at 1.16 mm to achieve a high-attenuation microwave absorption. The exceptional performance of NixSy@De for the absorption of electromagnetic waves (EMWs) is based on its high dielectric loss, substantial magnetic loss, and excellent impedance matching. This work combines transition metal sulfides with three-dimensional biotemplated diatomite, providing valuable insights into the design of advanced EMW absorbing materials.

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