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1.
Biomaterials ; 307: 122526, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38513434

RESUMEN

Stem cell therapies have shown great potential for treating myocardial infarction (MI) but are limited by low cell survival and compromised functionality due to the harsh microenvironment at the disease site. Here, we presented a Mesenchymal stem cell (MSC) spheroid-based strategy for MI treatment by introducing a protein/polyphenol self-assembling armor coating on the surface of cell spheroids, which showed significantly enhanced therapeutic efficacy by actively manipulating the hostile pathological MI microenvironment and enabling versatile functionality, including protecting the donor cells from host immune clearance, remodeling the ROS microenvironment and stimulating MSC's pro-healing paracrine secretion. The underlying mechanism was elucidated, wherein the armor protected to prolong MSCs residence at MI site, and triggered paracrine stimulation of MSCs towards immunoregulation and angiogenesis through inducing hypoxia to provoke glycolysis in stem cells. Furthermore, local delivery of coated MSC spheroids in MI rat significantly alleviated local inflammation and subsequent fibrosis via mediation macrophage polarization towards pro-healing M2 phenotype and improved cardiac function. In general, this study provided critical insight into the enhanced therapeutic efficacy of stem cell spheroids coated with a multifunctional armor. It potentially opens up a new avenue for designing immunomodulatory treatment for MI via stem cell therapy empowered by functional biomaterials.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Infarto del Miocardio , Ratas , Animales , Infarto del Miocardio/patología , Células Madre/patología , Esferoides Celulares/patología , Cicatrización de Heridas
2.
Mater Today Bio ; 24: 100930, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38293631

RESUMEN

Three-dimensional (3D) bioprinting has emerged as a groundbreaking technology for fabricating intricate and functional tissue constructs. Central to this technology are the bioinks, which provide structural support and mimic the extracellular environment, which is crucial for cellular executive function. This review summarizes the latest developments in microparticulate inks for 3D bioprinting and presents their inherent challenges. We categorize micro-particulate materials, including polymeric microparticles, tissue-derived microparticles, and bioactive inorganic microparticles, and introduce the microparticle ink formulations, including granular microparticles inks consisting of densely packed microparticles and composite microparticle inks comprising microparticles and interstitial matrix. The formulations of these microparticle inks are also delved into highlighting their capabilities as modular entities in 3D bioprinting. Finally, existing challenges and prospective research trajectories for advancing the design of microparticle inks for bioprinting are discussed.

3.
Biofabrication ; 15(2)2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36595285

RESUMEN

Extrusible biomaterials have recently attracted increasing attention due to the desirable injectability and printability to allow minimally invasive administration and precise construction of tissue mimics. Specifically, self-healing colloidal gels are a novel class of candidate materials as injectables or printable inks considering their fascinating viscoelastic behavior and high degree of freedom on tailoring their compositional and mechanical properties. Herein, we developed a novel class of adaptable and osteogenic composite colloidal gels via electrostatic assembly of gelatin nanoparticles and nanoclay particles. These composite gels exhibited excellent injectability and printability, and remarkable mechanical properties reflected by the maximal elastic modulus reaching ∼150 kPa combined with high self-healing efficiency, outperforming most previously reported self-healing hydrogels. Moreover, the cytocompatibility and the osteogenic capacity of the colloidal gels were demonstrated by inductive culture of MC3T3 cells seeded on the three-dimensional (3D)-printed colloidal scaffolds. Besides, the biocompatibility and biodegradability of the colloidal gels was provedin vivoby subcutaneous implantation of the 3D-printed scaffolds. Furthermore, we investigated the therapeutic capacity of the colloidal gels, either in form of injectable gels or 3D-printed bone substitutes, using rat sinus bone augmentation model or critical-sized cranial defect model. The results confirmed that the composite gels were able to adapt to the local complexity including irregular or customized defect shapes and continuous on-site mechanical stimuli, but also to realize osteointegrity with the surrounding bone tissues and eventually be replaced by newly formed bones.


Asunto(s)
Gelatina , Osteogénesis , Ratas , Animales , Arcilla , Regeneración Ósea , Hidrogeles/farmacología , Ingeniería de Tejidos , Andamios del Tejido , Impresión Tridimensional
4.
Front Immunol ; 13: 872832, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36119025

RESUMEN

Bacterial meningitis (BM) is a common life-threatening infection in children that occurs in the central nervous system (CNS). The cytologic examination of cerebrospinal fluid (CSF) is a key parameter in the diagnosis of BM, but the heterogeneity of cells in the CSF has not been elucidated, which limits the current understanding of BM neuroinflammation. In this study, CSF samples were collected from a number of BM patients who were in different stages of disease progression. Single-cell RNA-sequencing (scRNA-seq), with additional bulk transcriptome sequencing, was conducted to decipher the characteristics of CSF cells in BM progression. A total of 18 immune cell clusters in CSF were identified, including two neutrophils, two monocytes, one macrophage, four myeloid dendritic cells, five T cells, one natural killer cell, one B cell, one plasmacytoid dendritic cell, and one plasma cell subtype. Their population profiles and dynamics in the initial onset, remission, and recovery stages during BM progression were also characterized, which showed decreased proportions of myeloid cells and increased proportions of lymphoid cells with disease progression. One novel neutrophil subtype, FFAR2+TNFAIP6+ neutrophils, and one novel monocyte subtype, THBS1+IL1B+ monocytes, were discovered, and their quantity changes positively correlated with the intensity of the inflammatory response in the CSF during BM. In addition, the CSF of BM patients with unsatisfactory therapeutic responses presented with different cell heterogeneity compared to the CSF of BM patients with satisfactory therapeutic responses, and their CSF featured altered intercellular communications and increased proportions of type II myeloid dendritic cells and plasmacytoid dendritic cells. Moreover, the bulk transcriptome profiles of autologous CSF cells and peripheral blood leukocytes of BM patients showed that the immune cells in these two physiological compartments exhibited distinct immune responses under different onset conditions. In particular, the CSF cells showed a high expression of macrophage characteristic genes and a low expression of platelet characteristic genes compared with peripheral blood leukocytes. Our study conducted an in-depth exploration of the characteristics of CSF cells in BM progression, which provided novel insights into immune cell engagement in acute CNS infection.


Asunto(s)
Meningitis Bacterianas , Niño , Progresión de la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Meningitis Bacterianas/genética , Monocitos , ARN
5.
Microbes Infect ; 24(5): 104973, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35378326

RESUMEN

A rarely reported clinical specimen of Aspergillus spinulosporus was isolated from an immunocompetent 22-month-old boy who was suffering from central nervous system aspergillosis and meningitis. The patient had no comorbidity, organ transplantation, or other surgical operations that lead to invasive aspergillosis. A. spinulosporus is mostly a soil borne strain, and only three invasive aspergillosis cases involving this strain have been reported. We isolated this strain from cerebrospinal fluid, cultured it successfully on PDA medium, and named it BJCH M5. We performed a complete genomic and phenotypic analysis, evolutionary relationship, secondary metabolites analysis, identification of virulence factor, and pairwise synteny analysis. We sequenced the complete 31.6 MB genome of A. spinulosporus, including the eight chromosomes and mitochondria. 11,356 protein-coding genes were predicted. BJCHM 5 has a high sequence identity with ten virulent factors of Aspergillus fumigatus. It also encodes two unique BGCs (Biosynthetic gene clusters) which are involved in human infection. Pairwise synteny analysis demonstrated that this strain has chromosome arrangement differences from A. nidulans. In conclusion, we isolated a specimen of the rarely reported pathogen A. spinulosporus and performed a complete genome assembly and functional characteristic analysis.


Asunto(s)
Aspergilosis , Infecciones del Sistema Nervioso Central , Aspergilosis/genética , Aspergillus fumigatus/genética , Infecciones del Sistema Nervioso Central/genética , Humanos , Lactante , Masculino , Familia de Multigenes , Virulencia/genética
6.
Pediatr Infect Dis J ; 40(2): 109-115, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33044433

RESUMEN

BACKGROUND: There are limit studies about pediatric brain abscess in China. The aim of this study was to analyze clinical characteristics and outcomes of pediatric brain abscess in recent years in China. METHODS: The clinical information of children with brain abscess hospitalized in Beijing Children's Hospital between January 1, 2007 and December 31, 2016 were retrospectively reviewed. RESULTS: Ninety-four children were enrolled in this study. A Streptococcus milleri group (13.8%) was identified as the most common causative organisms, followed by Staphylococcus aureus (6.4%). The overall mortality was 21.6%, with 50.0% of deaths happening in the first week after diagnosis. Long-term outcomes of 74 patients were assessed with Glasgow Outcome Scale-Extended Pediatric Reversion: 50 patients with a score of 1-2 (favorable outcome) and 24 patients with a score of 3-8 (unfavorable outcome). Patients with multiple abscesses (P = 0.029) and intraventricular rupture of brain abscess/hydrocephalus (P = 0.024) had higher risk of unfavorable outcomes. CONCLUSIONS: Brain abscess is a serious disease with high mortality in children; more aggressive treatments should be considered in the first week of diagnosis because of high risk of death, and for patients with multiple brain abscesses and intraventricular rupture of brain abscess/hydrocephalus because of their higher risk of unfavorable.


Asunto(s)
Infecciones Bacterianas/microbiología , Infecciones Bacterianas/patología , Absceso Encefálico/microbiología , Absceso Encefálico/patología , Bacterias/clasificación , Bacterias/aislamiento & purificación , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/terapia , Beijing/epidemiología , Absceso Encefálico/epidemiología , Absceso Encefálico/terapia , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Resultado del Tratamiento
7.
ACS Appl Mater Interfaces ; 11(40): 36458-36468, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31509371

RESUMEN

Hydrogels that are capable of wet adhesion and self-healing can enable major advances in a variety of biomedical applications such as tissue regeneration, wound dressings, wearable/implantable devices, and drug delivery. We hereby developed an innovative but simple strategy to achieve adhesive, self-healing, and highly stretchable double-network hydrogels, which were composed of a primary covalent polyethylene glycol diacrylate (PEGDA) network in combination with a noncovalent network of highly diffusive, giant PEG chains. The adhesion to substrates including tissue matrices was instant and repeatable due to the diffusive PEG chains that can spontaneously penetrate and entangle with the substrate network. Combining the intrinsic biocompatibility of PEG and rational design for tuning the hydrogel network properties, we exemplarily demonstrated that this hydrogel can be used as a three-dimensional matrix for cell culture or as a tissue adhesive for wound healing. The in vivo study showed that the hydrogel is capable of effectively triggering skin wound healing with a significantly lower immune response in comparison to commercial tissue adhesives currently used in clinics. Therefore, our study provides new and critical insights into the design strategy to achieve adhesion and rehealability by taking advantages of the entanglement effect from double-network hydrogels and opens up a new avenue for the application of entanglement-driven hydrogels in regenerative medicine.


Asunto(s)
Hidrogeles/farmacología , Polietilenglicoles/farmacología , Adhesivos Tisulares/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Línea Celular , Matriz Extracelular/metabolismo , Ratones , Ratas , Estrés Mecánico
8.
Pediatr Investig ; 2(2): 134-136, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32851248
9.
Zhen Ci Yan Jiu ; 35(1): 56-60, 2010 Feb.
Artículo en Chino | MEDLINE | ID: mdl-20458909

RESUMEN

OBJECTIVE: To compare the therapeutic effects of different acupuncture methods in improving the myodynamia and neuronfunction of patients with acute cerebral infarction (ACI). METHODS: A total of 90 ACI patients were randomized into ear-acupuncture, scalp-acupuncture and body-acupuncture groups, with 30 cases in each. For patients of ear-acupuncture group, the main otopoints used for penetrative needling were Zhen(MA-AT)-Nie(MA-AT)-E(MA-AT) on the affected side in combination with Jian(MA-SF 4)-Suogu(MA-SF 5) and Zhou(MA-SF 3)-Wan(MA-SF 2)-Zhi(MA-SF 1) for upper-limb paralysis, and with Tun (MA-AH 5)-Zuogushenjing(MA-AH 6), Kuan(MA-AH 4)-Xi(MA-AH 3), and Xi(MA-AH 3)-Huai(MA-AH 2)-Zhi(MA-AH 1) for lower-limb paralysis, and body acupoints as Jianyu(LI 15), Hegu(LI 4), Huantiao(GB 30), Taixi(KI 3), etc. For patients of scalp-acupuncture group, scalp-points used were Dingnie Qianxiexian(MS 6) and Dingnie Houxiexian(MS 7) on the healthy side, and combined with body acupoints (the same as those mentioned above). For patients of body-acupuncture group, only body acupoints were used. The treatment was given once daily for 14 days. RESULTS: Comparison among 3 groups showed that the increased myodynamia of both upper and lower limbs in ear-acupuncture and scalp-acupuncture groups was significantly superior to that of body-acupuncture group (P < 0.01). The neurofunctional deficit scores of ear-acupuncture and scalp-acupuncture groups were significantly lower than that of body-acupuncture group (P < 0.01) after the treatment. In comparison with pre-acupuncture, the neurofunctional deficit scores of the 3 groups lessened considerably after the treatment (P < 0.01). Of the 30 cases in each of earacupuncture, scalp-acupuncture and body-acupuncture groups, 0, 1 and 0 were cured basically, 21, 18 and 4 experienced marked improvement, 9, 11 and 20 were improved, 0, 0 and 6 failed, respectively. The therapeutic effects of ear-acupuncture and scalp-acupuncture were obviously superior to that of body-acupuncture group (P < 0.01). No significant differences were found between ear-acupuncture and scalp-acupuncture groups in myodynamia improvement, neurofunctional deficit scores and clinical curative effect (P > 0.05). CONCLUSION: Acupuncture can effectively improve ACI patients' clinical symptoms and the therapeutic effect of ear-acupuncture and scalp-acupuncture was superior to that of simple body acupuncture.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Infarto Cerebral/terapia , Músculos/fisiopatología , Sistema Nervioso/fisiopatología , Anciano , Infarto Cerebral/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
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