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1.
J Am Chem Soc ; 145(6): 3312-3317, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36728932

RESUMEN

Developing magnetic ultrasoft robots to navigate through extraordinarily narrow and confined spaces like capillaries in vivo requires synthesizing materials with excessive deformability, responsive actuation, and rapid adaptability, which are difficult to achieve with the current soft polymeric materials, such as elastomers and hydrogels. We report a magnetically actuatable and water-immiscible (MAWI) coacervate based on the assembled magnetic core-shell nanoparticles to function as a liquid robot. The degradable and biocompatible millimeter-sized MAWI coacervate liquid robot can remain stable under changing pH and salt concentrations, release loaded cargoes on demand, squeeze through an artificial capillary network within seconds, and realize intravascular targeting in vivo guided by an external magnetic field. We believe the proposed "coacervate-based liquid robot" can implement demanding tasks beyond the capability of conventional elastomer or hydrogel-based soft robots in the field of biomedicine and represents a distinct design strategy for high-performance ultrasoft robots.


Asunto(s)
Robótica , Agua , Diseño de Equipo , Fenómenos Físicos , Elastómeros , Fenómenos Magnéticos
2.
Int J Neurosci ; 133(5): 492-495, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-33931000

RESUMEN

BACKGROUND:  In the literature, filum terminale arteriovenous shunts (FTAVSs) always feature a single shunt point. Nidus-type FTAVSs have rarely been reported, and the best treatment strategy is unclear. This is a report of one exceptional case of a nidus-type FTAVS and surgical treatment of the lesion. CASE DESCRIPTION: The patient suffered from cauda equina syndrome for 9 months. Magnetic resonance imaging and spinal angiography revealed a nidus-type FTAVF at the L2 level. Surgical resection was performed in the hybrid operating room, and the nidus was completely resected with the assistance of intraoperative methylene blue angiography and neurophysiological monitoring. The postoperative neurological function was stable. CONCLUSIONS: A nidus-type arteriovenous shunt could originate from the FT, and in such cases, complete surgical resection with intraoperative neurophysiological monitoring in a hybrid operating room should be suggested.


Asunto(s)
Fístula Arteriovenosa , Cauda Equina , Humanos , Cauda Equina/diagnóstico por imagen , Cauda Equina/cirugía , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/cirugía , Fístula Arteriovenosa/patología , Procedimientos Neuroquirúrgicos/métodos , Imagen por Resonancia Magnética , Angiografía de Substracción Digital/métodos
3.
Neurosciences (Riyadh) ; 28(1): 42-47, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36617452

RESUMEN

OBJECTIVES: To explore the clinicopathological features and prognosis of multifocal high-grade gliomas (M-HGGs) with H3F3A mutation in adults. METHODS: Four adult patients with H3F3A-mutant M-HGGs who were treated at our institution from August 2020 to December 2021 were reviewed, including clinical, pathological and radiologic data. A series of 16 adult patients with M-HGGs without H3F3A mutation was used as a comparative group. Progression-free survival (PFS) and overall survival (OS) were compared between the groups using the Kaplan-Meier method. RESULTS: All patients were IDH wild-type and TERT wild-type, and P53 was overexpressed. A patient with the H3 G34R mutation and 1 of 3 patients with the H3 K27 M mutation had MGMT promoter methylation. The lesions with the H3 G34R mutation were located in the cerebral hemisphere; the lesions with H3 K27 alterations were mainly in the midline structure, and the cerebral hemisphere could also be involved. One patient underwent subtotal resection (STR), and 3 patients underwent biopsy. All patients received radiotherapy, and the median PFS and OS were 9.5 months and 14.5 months, respectively. The clinical outcomes were similar to those of non-H3F3A-mutated M-HGGs patients (median PFS and OS were 7.0 months and 18.0 months, respectively). CONCLUSION: We describe the clinicopathological features and outcomes of 4 adult M-HGGs patients with H3F3A mutation, and found this mutation doesn't appear to have a negative outcome with the administration of current therapies.


Asunto(s)
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/terapia , Pronóstico , Mutación/genética
4.
Stroke ; 52(12): 3873-3882, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34412511

RESUMEN

BACKGROUND AND PURPOSE: Paravertebral arteriovenous shunts (PVAVSs) are rare. Whether the intradural venous system is involved in drainage may lead to differences in clinical characteristics through specific pathophysiological mechanisms. This study aims to comprehensively evaluate the natural history and clinical outcomes of PVAVSs with or without intradural drainage. METHODS: Sixty-four consecutive patients with PVAVSs from 2 institutes were retrospectively reviewed. Lesions were classified as type A (n=28) if the intradural veins were involved in drainage; otherwise, they were classified as type B (n=36). The clinical course from initial presentation to the last follow-up was analyzed. RESULTS: The patients with type A shunts were older at presentation (52.5 versus 35.5 years, P<0.0001) and more likely to have lower spinal segments affected than patients with type B PVAVSs (67.8% versus 13.9%, P=0.00006). After presentation, the deterioration rates related to gait and sphincter dysfunction were significantly higher in patients with type A than type B shunts (gait dysfunction: 71.8%/y versus 17.0%/y, P=0.0006; sphincter dysfunction: 63.7%/y versus 11.3%/y, P=0.0002). According to the angiogram at the end of the latest treatment, 79% of type A and 75% of type B PVAVSs were completely obliterated. If the lesions were partially obliterated, a significantly higher clinical deterioration rate was observed in patients with type A shunts than those with type B shunts (69.9%/y versus 3.2%/y, P=0.0253). CONCLUSIONS: Type A PVAVSs feature rapid progressive neurological deficits; therefore, early clinical intervention is necessary. For complex lesions that cannot be completely obliterated, surgical disconnection of all refluxed radicular veins is suggested.


Asunto(s)
Fístula Arteriovenosa/patología , Fístula Arteriovenosa/terapia , Malformaciones Vasculares del Sistema Nervioso Central/patología , Malformaciones Vasculares del Sistema Nervioso Central/terapia , Médula Espinal/irrigación sanguínea , Adulto , Anciano , Embolización Terapéutica/métodos , Femenino , Humanos , Masculino , Microcirugia/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Médula Espinal/patología , Procedimientos Quirúrgicos Vasculares/métodos
5.
BMC Surg ; 21(1): 117, 2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33676461

RESUMEN

BACKGROUND: Osteopetrosis is a genetic disease characterized by defects in osteoclast formation and function. There were a few cases of subtrochanteric femur fractures treated with dynamic hip screw (DHS) in patients with osteopetrosis, but unfortunately the healing outcome was rather poor. CASE PRESENTATION: We present our experience for treating a patient with intermediate autosomal recessive osteopetrosis (IRO) suffering from subtrochanteric femur fracture. In this case, we successfully used dynamic hip screw (DHS) internal fixation through meticulous preoperative planning and postoperative care, as well as application of surgical techniques. The patient displayed stable internal fixation with no limitation of activities during follow-up for 15 months. In addition to this case, a review of previous case reports showed an increasing number of case reports demonstrating that surgical treatment-related complications could be avoided preoperatively, intraoperatively, and postoperatively. CONCLUSION: DHS for this patient, who suffered from subtrochanteric fractures with osteopetrosis, was successfully implemented. In the light of a comprehensive literature review, preoperative planning, surgical techniques, and postoperative rehabilitation care can significantly reduce the complications.


Asunto(s)
Fracturas de Cadera , Osteopetrosis , Tornillos Óseos , Fijación Interna de Fracturas , Fracturas de Cadera/etiología , Fracturas de Cadera/cirugía , Humanos , Osteopetrosis/complicaciones , Resultado del Tratamiento
6.
Curr Osteoporos Rep ; 18(6): 621-632, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33030684

RESUMEN

PURPOSE OF REVIEW: The goals of this review are two folds: (1) to describe the recent understandings on the roles of calcitonin gene-related peptide-α (CGRP) in bone homeostasis and the underlying mechanisms of related neuronal regulation and (2) to propose innovative CGRP-modulated approaches for enhancing bone regeneration in challenging bone disorders. RECENT FINDINGS: CGRP is predominantly produced by the densely distributed sensory neuronal fibers in bone, declining with age. Under mechanical and biochemical stimulations, CGRP releases and exerts either physiological or pathophysiological roles. CGRP at physiological level orchestrates the communications of bone cells with cells of other lineages, affecting not only osteogenesis, osteoclastogenesis, and adipogenesis but also angiogenesis, demonstrating with pronounced anabolic effect, thus is essential for maintaining bone homeostasis, with tuned nerve-vessel-bone network. In addition, its effects on immunity and cell recruitment are also crucial for bone fracture healing. Binding to the G protein-coupled receptor composited by calcitonin receptor-like receptor (CRLR) and receptor activity modifying protein 1 (RAMP1) on cellular surface, CGRP triggers various intracellular signaling cascades involving cyclic adenosine monophosphate (cAMP) and cAMP response element-binding protein (CREB). Peaking at early stage post-fracture, CGRP promotes bone formation, displaying with larger callus. Then CGRP gradually decreases over time, allowing normal or physiological bone remodeling. By elevating CGRP at early stage, low-intensity pulsed ultrasound (LIPUS), electrical stimulation, and magnesium-based bio-mineral products may promisingly accelerate bone regeneration experimentally in medical conditions like osteoporosis, osteoporotic fracture, and spine fusion. Excess CGRP expression is commonly observed in pathological conditions including cancer metastatic lesions in bone and fracture delayed- or non-healing, resulting in persistent chronic pain. To date, these discoveries have largely been limited to animal models. Clinical applications are highly desirable. Compelling evidence show the anabolic effects of CGRP on bone in animals. However, further validation on the role of CGRP and the underlying mechanisms in human skeletons is required. It remains unclear if it is type H vessel connecting neuronal CGRP to osteogenesis, and if there is only specific rather than all osteoprogenitors responsible to CGRP. Clear priority should be put to eliminate these knowledge gaps by integrating with high-resolution 3D imaging of transparent bulk bone and single-cell RNA-sequencing. Last but not the least, given that small molecule antagonists such as BIBN4096BS can block the beneficial effects of CGRP on bone, concerns on the potential side effects of humanized CGRP-neutralizing antibodies when systemically administrated to treat migraine in clinics are arising.


Asunto(s)
Regeneración Ósea/fisiología , Péptido Relacionado con Gen de Calcitonina/fisiología , Homeostasis/fisiología , Osteogénesis/fisiología , Animales , Curación de Fractura/fisiología , Humanos , Transducción de Señal
7.
Small ; 15(51): e1904486, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31755651

RESUMEN

Magnesium (Mg) alloys have been promised for biomedical implants in orthopedic field, however, the fast corrosion rate and mode challenge their clinical application. To push Mg alloys materials into practice, a composite coating with biodegradable and high compatible components to improve anticorrosion property of an Mg alloy (i.e., AZ31) is designed and fabricated. The inner layer is micro-nano structured Mg(OH)2 through hydrothermal treatment. Then stearic acid (SA) is introduced to modify Mg(OH)2 for better reducing the gap below a surface-degradation polymer layer of poly(1,3-trimethylene carbonate). Benefited by the SA modification effect, this sandwiched coating avoids corrosive medium penetration via enhancing the adhesion strength at the interface between outer and inner layers. Both in vitro and in vivo tests indicate that the composite coating modified AZ31 perform a better anticorrosion behavior and biocompatibility compared to bare AZ31. Strikingly, a 1.7-fold improvement in volume of newly formed bone is observed surrounding the composite coating modified implant after 12 week implantation. The sandwiched biocompatible coating strategy paves a hopeful way for future translational application of Mg alloys orthopedic materials in clinics.


Asunto(s)
Implantes Absorbibles , Aleaciones/química , Magnesio/química , Materiales Biocompatibles Revestidos/química , Ácidos Esteáricos/química
8.
Ann Rheum Dis ; 78(4): 551-561, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30745310

RESUMEN

OBJECTIVES: Wnt16 is implicated in bone fracture and bone mass accrual both in animals and humans. However, its functional roles and molecular mechanism in chondrocyte differentiation and osteoarthritis (OA) pathophysiology remain largely undefined. In this study, we analysed its mechanistic association and functional relationship in OA progression in chondrocyte lineage. METHODS: The role of Wnt16 during skeletal development was examined by Col2a1-Wnt16 transgenic mice and Wnt16fl/fl;Col2a1-Cre (Wnt16-cKO) mice. OA progression was assessed by micro-CT analysis and Osteoarthritis Research Society International score after anterior cruciate ligament transection (ACLT) surgery with Wnt16 manipulation by adenovirus intra-articular injection. The molecular mechanism was investigated in vitro using 3D chondrocyte pellet culture and biochemical analyses. Histological analysis was performed in mouse joints and human cartilage specimens. RESULTS: Wnt16 overexpression in chondrocytes in mice significantly inhibited chondrocyte hypertrophy during skeletal development. Wnt16 deficiency exaggerated OA progression, whereas intra-articular injection of Ad-Wnt16 markedly attenuated ACLT-induced OA. Cellular and molecular analyses showed that, instead of ß-catenin and calcium pathways, Wnt16 activated the planar cell polarity (PCP) and JNK pathway by interacting mainly with AP2b1, and to a lesser extend Ror2 and CD146, and subsequently induced PTHrP expression through phosphor-Raptor mTORC1 pathway. CONCLUSIONS: Our findings indicate that Wnt16 activates PCP/JNK and crosstalks with mTORC1-PTHrP pathway to inhibit chondrocyte hypertrophy. Our preclinical study suggests that Wnt16 may be a potential therapeutic target for OA treatment.


Asunto(s)
Artritis Experimental/patología , Osteoartritis/patología , Proteínas Wnt/fisiología , Animales , Artritis Experimental/metabolismo , Artritis Experimental/fisiopatología , Cartílago Articular/metabolismo , Cartílago Articular/patología , Diferenciación Celular/fisiología , Polaridad Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Condrocitos/patología , Condrocitos/fisiología , Progresión de la Enfermedad , Humanos , Hipertrofia/prevención & control , Sistema de Señalización de MAP Quinasas/fisiología , Diana Mecanicista del Complejo 1 de la Rapamicina/fisiología , Ratones Transgénicos , Osteoartritis/metabolismo , Osteoartritis/fisiopatología , Proteína Relacionada con la Hormona Paratiroidea/fisiología , Proteínas Wnt/deficiencia , Proteínas Wnt/metabolismo
9.
Nanomedicine ; 13(1): 111-121, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27621054

RESUMEN

Specific detection of various tumor types remains crucial for designing effective treatment strategies. We demonstrate photoacoustic imaging (PAI) using high-affinity and high-specificity peptide-based probes for accurate and specific diagnosis of osteosarcoma. Herein, two new tumor-specific oligopeptides, termed PT6 and PT7, were identified using phage display-based screening on an osteosarcoma cell line (UMR-106). The identified oligopeptides were able to detect clinical osteosarcoma samples on tissue microarrays. Oligopeptide-conjugated PEGylated gold nanorods (PGNR) were designed to specifically target UMR-106 cells. More importantly, PAI revealed that both PGNR-PT6 and PGNR-PT7 could bind selectively to subcutaneous UMR-106 xenografts after systemic administration and enhance the contrast of osteosarcoma images by 170% and 230%, respectively, compared to tumor-bearing mice injected with PGNRs conjugated to scrambled oligopeptides. PAI employing PGNRs conjugated to specifically designed nanoprobes may provide a new method for tumor type-specific diagnosis of osteosarcoma.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Osteosarcoma/diagnóstico por imagen , Biblioteca de Péptidos , Técnicas Fotoacústicas , Animales , Línea Celular Tumoral , Oro/química , Células HEK293 , Humanos , Nanopartículas del Metal/química , Ratones , Trasplante de Neoplasias , Oligopéptidos
10.
Nanomedicine ; 12(6): 1453-62, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27046663

RESUMEN

Imaging is routinely used for clinical and diagnostic purposes, but techniques capable of high specificity and resolution for the early detection of nerve injury are still limited. In this study, we found that heat shock protein 27 (HSP27) becomes highly upregulated within 3 to 7 days of nerve injury. Taking advantage of this expression pattern, we conjugated gold nanorods (GNRs) to HSP27-specific antibodies to generate a nanoprobe (GNR-HSP27Abs) that could be targeted to the site of nerve injury and detected by near-infrared photoacoustic imaging. Notably, photoacoustic images acquired 12hours after local administration of GNR-HSP27Abs demonstrated that the nanoprobe can distinguish between injured and uninjured nerves in rats. Taken together, these findings expand the application of nanoprobe-targeted photoacoustic imaging to the detection of injured nerves, and prompt further development of this novel imaging platform for clinical application.


Asunto(s)
Imagen Óptica/métodos , Técnicas Fotoacústicas/métodos , Análisis Espectral , Traumatismos del Sistema Nervioso/diagnóstico por imagen , Animales , Anticuerpos , Oro , Proteínas de Choque Térmico HSP27 , Nanotubos , Ratas
11.
Sci Adv ; 10(10): eadk6084, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457498

RESUMEN

The emerging therapeutic strategies for osteoarthritis (OA) are shifting toward comprehensive approaches that target periarticular tissues, involving both cartilage and subchondral bone. This shift drives the development of single-component therapeutics capable of acting on multiple tissues and cells. Magnesium, an element essential for maintaining skeletal health, shows promise in treating OA. However, the precise effects of magnesium on cartilage and subchondral bone are not yet clear. Here, we investigated the therapeutic effect of Mg2+ on OA, unveiling its protective effects on both cartilage and bone at the cellular and animal levels. The beneficial effect on the cartilage-bone interaction is primarily mediated by the PI3K/AKT pathway. In addition, we developed poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with nano-magnesium oxide modified with stearic acid (SA), MgO&SA@PLGA, for intra-articular injection. These microspheres demonstrated remarkable efficacy in alleviating OA in rat models, highlighting their translational potential in clinical applications.


Asunto(s)
Cartílago Articular , Nanopartículas , Osteoartritis , Ratas , Animales , Óxido de Magnesio/farmacología , Magnesio/farmacología , Fosfatidilinositol 3-Quinasas , Osteoartritis/tratamiento farmacológico
12.
Theranostics ; 14(10): 3963-3983, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38994033

RESUMEN

Piezo1, a mechanosensitive ion channel, has emerged as a key player in translating mechanical stimuli into biological signaling. Its involvement extends beyond physiological and pathological processes such as lymphatic vessel development, axon growth, vascular development, immunoregulation, and blood pressure regulation. The musculoskeletal system, responsible for structural support, movement, and homeostasis, has recently attracted attention regarding the significance of Piezo1. This review aims to provide a comprehensive summary of the current research on Piezo1 in the musculoskeletal system, highlighting its impact on bone formation, myogenesis, chondrogenesis, intervertebral disc homeostasis, tendon matrix cross-linking, and physical activity. Additionally, we explore the potential of targeting Piezo1 as a therapeutic approach for musculoskeletal disorders, including osteoporosis, muscle atrophy, intervertebral disc degeneration, and osteoarthritis.


Asunto(s)
Canales Iónicos , Enfermedades Musculoesqueléticas , Humanos , Canales Iónicos/metabolismo , Animales , Enfermedades Musculoesqueléticas/metabolismo , Sistema Musculoesquelético/metabolismo , Condrogénesis/fisiología , Mecanotransducción Celular , Osteogénesis/fisiología , Desarrollo de Músculos
13.
Biomed Mater ; 19(4)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38815612

RESUMEN

Magnesium (Mg) has gained widespread recognition as a potential revolutionary orthopedic biomaterial. However, whether the biodegradation of the Mg-based orthopedic implants would pose a risk to patients with chronic kidney disease (CKD) remains undetermined as the kidney is a key organ regulating mineral homeostasis. A rat CKD model was established by a 5/6 subtotal nephrectomy approach, followed by intramedullary implantation of three types of pins: stainless steel, high pure Mg with high corrosion resistance, and the Mg-Sr-Zn alloy with a fast degradation rate. The long-term biosafety of the biodegradable Mg or its alloys as orthopedic implants were systematically evaluated. During an experimental period of 12 weeks, the implantation did not result in a substantial rise of Mg ion concentration in serum or major organs such as hearts, livers, spleens, lungs, or kidneys. No pathological changes were observed in organs using various histological techniques. No significantly increased iNOS-positive cells or apoptotic cells in these organs were identified. The biodegradable Mg or its alloys as orthopedic implants did not pose an extra health risk to CKD rats at long-term follow-up, suggesting that these biodegradable orthopedic devices might be suitable for most target populations, including patients with CKD.


Asunto(s)
Implantes Absorbibles , Aleaciones , Magnesio , Insuficiencia Renal Crónica , Animales , Magnesio/química , Aleaciones/química , Ratas , Insuficiencia Renal Crónica/terapia , Insuficiencia Renal Crónica/metabolismo , Masculino , Ratas Sprague-Dawley , Materiales Biocompatibles/química , Ensayo de Materiales , Riñón/metabolismo , Riñón/patología , Acero Inoxidable/química , Corrosión
14.
Bone ; 183: 117094, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582289

RESUMEN

The present study aimed to establish and evaluate a preclinical model of steroid-associated osteonecrosis (SAON) in mice. Sixteen 24-week-old male C57BL/6 mice were used to establish SAON by two intraperitoneal injections of lipopolysaccharide (LPS), followed by three subcutaneous injections of methylprednisolone (MPS). Each injection was conducted on working day, with an interval of 24 h. Six cycles of injections were conducted. Additional twelve mice (age- and gender-matched) were used as normal controls. At 2 and 6 weeks after completing induction, bilateral femora and bilateral tibiae were collected for histological examination, micro-CT scanning, and bulk RNA sequencing. All mice were alive until sacrificed at the indicated time points. The typical SAON lesion was identified by histological evaluation at week 2 and week 6 with increased lacunae and TUNEL+ osteocytes. Micro-CT showed significant bone degeneration at week 6 in SAON model. Histology and histomorphometry showed significantly lower Runx2+ area, mineralizing surface (MS/BS), mineral apposition rate (MAR), bone formation rate (BFR/BS), type H vessels, Ki67+ (proliferating) cells, and higher marrow fat fraction, osteoclast number and TNFα+ areas in SAON group. Bulk RNA-seq revealed changed canonical signaling pathways regulating cell cycle, angiogenesis, osteogenesis, and osteoclastogenesis in the SAON group. The present study successfully established SAON in mice with a combination treatment of LPS and MPS, which could be considered a reliable and reproducible animal model to study the pathophysiology and molecular mechanism of early-stage SAON and to develop potential therapeutic approaches for the prevention and treatment of SAON.


Asunto(s)
Lipopolisacáridos , Osteonecrosis , Masculino , Ratones , Animales , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Osteonecrosis/tratamiento farmacológico , Esteroides , Osteogénesis , Metilprednisolona/uso terapéutico
15.
Theranostics ; 14(15): 5999-6015, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39346542

RESUMEN

The process of skeletal regeneration initiated by stem cells following injury, especially in fractures, is significantly impaired by aging and adverse factors. Nicotinamide mononucleotide (NMN), a critical endogenous precursor of nicotinamide adenine dinucleotide (NAD), has garnered extensive attention for its multifaceted regulatory functions in living organisms and its wide-ranging therapeutic potential. However, whether NMN contributes to trauma-induced skeletal regeneration remains unclear. Methods: The transverse femoral shaft fracture model was employed to evaluate the potential advantages of NMN administration for overall repair during the initial fracture stages in male mice through micro-CT analysis, histochemistry, and biomechanical testing. The pro-proliferative function of NMN on skeletal stem cells (SSCs) was investigated through flow cytometry, qRT-PCR, NAD content measurement, and cell proliferation assay. Results: In this study, we observed that the administration of NMN during the initial phase of fracture in mice led to a larger callus and corresponding improvement in micro-CT parameters. NMN enhances the cartilaginous component of the callus by elevating the NAD content, consequently accelerating subsequent endochondral ossification and the fracture healing process. Subsequent analyses elucidated that NMN was beneficial in promoting the expansion of diverse stem cells in vivo and in vitro potentially via modulation of the Notch signaling pathway. Moreover, the depletion of macrophages profoundly obstructs the proliferation of SSCs. Conclusion: Our discoveries provide a potential strategy for enhancing fracture healing through stimulation of callus SSC proliferation at an early stage, shedding light on the translational value of NMN as an enhancer for skeletal regeneration and highlighting the pivotal role of macrophage-stem cell interactions in governing the regenerative influence of NMN on stem cells.


Asunto(s)
Proliferación Celular , Curación de Fractura , Mononucleótido de Nicotinamida , Animales , Ratones , Proliferación Celular/efectos de los fármacos , Curación de Fractura/efectos de los fármacos , Mononucleótido de Nicotinamida/farmacología , Masculino , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Microtomografía por Rayos X , Osteogénesis/efectos de los fármacos , Modelos Animales de Enfermedad , Fracturas del Fémur/tratamiento farmacológico , Fracturas del Fémur/patología , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Callo Óseo/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , NAD/metabolismo
16.
Regen Biomater ; 11: rbae095, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39346687

RESUMEN

With mechanical strength close to cortical bone, biodegradable and osteopromotive properties, magnesium (Mg)-based implants are promising biomaterials for orthopedic applications. However, during the degradation of such implants, there are still concerns on the potential adverse effects such as formation of cavities, osteolytic phenomena and chronic inflammation. Therefore, to transform Mg-based implants into clinical practice, the present study evaluated the local effects of high-purity Mg screws (HP-Mg, 99.99 wt%) by comparing with clinically approved polylactic acid (PLA) screws in epiphyseal trabecular bone of rabbits. After implantation of screws at the rabbit distal femur, bone microstructural, histomorphometric and biomechanical properties were measured at various time points (weeks 4, 8 and 16) using micro-CT, histology and histomorphometry, micro-indentation and scanning electron microscope. HP-Mg screws promoted peri-implant bone ingrowth with higher bone mass (BV/TV at week 4: 0.189 ± 0.022 in PLA group versus 0.313 ± 0.053 in Mg group), higher biomechanical properties (hardness at week 4: 35.045 ± 1.000 HV in PLA group versus 51.975 ± 2.565 HV in Mg group), more mature osteocyte LCN architecture, accelerated bone remodeling process and alleviated immunoreactive score (IRS of Ram11 at week 4: 5.8 ± 0.712 in PLA group versus 3.75 ± 0.866 in Mg group) as compared to PLA screws. Furthermore, we conducted finite element analysis to validate the superiority of HP-Mg screws as orthopedic implants by demonstrating reduced stress concentration and uniform stress distribution around the bone tunnel, which led to lower risks of trabecular microfractures. In conclusion, HP-Mg screws demonstrated greater osteogenic bioactivity and limited inflammatory response compared to PLA screws in the epiphyseal trabecular bone of rabbits. Our findings have paved a promising way for the clinical application of Mg-based implants.

17.
Front Bioeng Biotechnol ; 12: 1352023, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38766649

RESUMEN

Osteochondral defect (OCD) is a common but challenging condition in orthopaedics that imposes huge socioeconomic burdens in our aging society. It is imperative to accelerate the R&D of regenerative scaffolds using osteochondral tissue engineering concepts. Yet, all innovative implant-based treatments require animal testing models to verify their feasibility, biosafety, and efficacy before proceeding to human trials. Rabbit models offer a more clinically relevant platform for studying OCD repair than smaller rodents, while being more cost-effective than large animal models. The core-decompression drilling technique to produce full-thickness distal medial femoral condyle defects in rabbits can mimic one of the trauma-relevant OCD models. This model is commonly used to evaluate the implant's biosafety and efficacy of osteochondral dual-lineage regeneration. In this article, we initially indicate the methodology and describe a minimally-invasive surgical protocol in a step-wise manner to generate a standard and reproducible rabbit OCD for scaffold implantation. Besides, we provide a detailed procedure for sample collection, processing, and evaluation by a series of subsequent standardized biochemical, radiological, biomechanical, and histological assessments. In conclusion, the well-established, easy-handling, reproducible, and reliable rabbit OCD model will play a pivotal role in translational research of osteochondral tissue engineering.

18.
Arch Pathol Lab Med ; 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38390749

RESUMEN

CONTEXT.­: Fumarate hydratase (FH)-deficient renal cell carcinoma (RCC) rarely exhibits a predominant tubulocystic architecture with few other components. RCC with pure tubules and cysts lined by eosinophilic tumor cells with prominent nucleoli would raise the diagnosis of tubulocystic RCC. It is important to differentiate the 2 entities because they lead to different outcomes. OBJECTIVE.­: To address the concern, a multicenter study was implemented to explore useful clinicopathologic features in differentiation between tubulocystic FH-deficient RCC and tubulocystic RCC. DESIGN.­: Clinical factors included age, sex, tumor size, and outcome. Morphologic factors included cell morphology, presence or absence of a nontubulocystic component, and stromal findings. Immunohistochemistry, fluorescence in situ hybridization, and next-generation sequencing were performed to explore the protein expression and molecular profiles of the 2 entities. RESULTS.­: We evaluated 6 patients with tubulocystic RCC and 10 patients with tubulocystic FH-deficient RCC. Tubulocystic RCC exhibited a small size (<4.0 cm, pT1a), low Ki-67 index (<5%), retained FH, and negative 2SC expression. Tubulocystic FH-deficient RCC had a relatively large size and a high Ki-67 index. Perinucleolar haloes, loss of FH, and 2SC positivity were always observed. Pure tubulocystic architecture was not observed in FH-deficient RCC, because focal nontubulocystic components can always be seen. CONCLUSIONS.­: We emphasized multiple sectioning to identify a nontubulocystic architecture to exclude tubulocystic RCC. Moreover, tumor size, FH/2SC staining, and the Ki-67 index can differentiate tubulocystic FH-deficient RCC from tubulocystic RCC. The diagnosis of tubulocystic RCC was not recommended in renal mass biopsy because of the limited tissues sampled.

19.
Adv Mater ; : e2312920, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39385647

RESUMEN

The healing of bone defects after debridement in medication-related osteonecrosis of the jaw (MRONJ) is a challenging medical condition with impaired angiogenesis, susceptible infection, and pro-inflammatory responses. Magnesium (Mg) nanocomposite hydrogel is developed to specifically tackle multiple factors involved in MRONJ. Mg-oxide nanoparticles tune the gelation kinetics in the reaction between N-hydroxysuccinimide-functionalized hyperbranched poly (ethylene glycol) and proteins. This reaction allows an enhanced mechanical property after instant solidification and, more importantly, also stable gelation in challenging environments such as wet and hemorrhagic conditions. The synthesized hydrogel guides mandible regeneration in MRONJ rats by triggering the formation of type H vessels, activating Osterix+ osteoprogenitor cells, and generating anti-inflammatory microenvironments. Additionally, this approach demonstrates its ability to suppress infection by inhibiting specific pathogens while strengthening stress tolerance in the affected alveolar bone. Furthermore, the enhanced osteogenic properties and feasibility of implantation of the hydrogel are validated in mandible defect and iliac crest defect created in minipigs, respectively. Collectively, this study offers an injectable and innovative bone substitute to enhance mandible defect healing by tackling multiple detrimental pathologies.

20.
Mil Med Res ; 11(1): 33, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816888

RESUMEN

Orthopedic conditions have emerged as global health concerns, impacting approximately 1.7 billion individuals worldwide. However, the limited understanding of the underlying pathological processes at the cellular and molecular level has hindered the development of comprehensive treatment options for these disorders. The advent of single-cell RNA sequencing (scRNA-seq) technology has revolutionized biomedical research by enabling detailed examination of cellular and molecular diversity. Nevertheless, investigating mechanisms at the single-cell level in highly mineralized skeletal tissue poses technical challenges. In this comprehensive review, we present a streamlined approach to obtaining high-quality single cells from skeletal tissue and provide an overview of existing scRNA-seq technologies employed in skeletal studies along with practical bioinformatic analysis pipelines. By utilizing these methodologies, crucial insights into the developmental dynamics, maintenance of homeostasis, and pathological processes involved in spine, joint, bone, muscle, and tendon disorders have been uncovered. Specifically focusing on the joint diseases of degenerative disc disease, osteoarthritis, and rheumatoid arthritis using scRNA-seq has provided novel insights and a more nuanced comprehension. These findings have paved the way for discovering novel therapeutic targets that offer potential benefits to patients suffering from diverse skeletal disorders.


Asunto(s)
Análisis de Secuencia de ARN , Análisis de la Célula Individual , Humanos , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Enfermedades Óseas/terapia , Enfermedades Óseas/fisiopatología , Huesos , Biología Computacional/métodos
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