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BACKGROUND: Osteoarthritis (OA) is a degenerative joint disease characterized by the progressive degeneration of articular cartilage, leading to pain, stiffness, and loss of joint function. The pathogenesis of OA involves multiple factors, including increased intracellular reactive oxygen species (ROS), enhanced chondrocyte apoptosis, and disturbances in cartilage matrix metabolism. These processes contribute to the breakdown of the extracellular matrix (ECM) and the loss of cartilage integrity, ultimately resulting in joint damage and dysfunction. RNA interference (RNAi) therapy has emerged as a promising approach for the treatment of various diseases, including hATTR and acute hepatic porphyria. By harnessing the natural cellular machinery for gene silencing, RNAi allows for the specific inhibition of target genes involved in disease pathogenesis. In the context of OA, targeting key molecules such as matrix metalloproteinase-13 (MMP13), which plays a critical role in cartilage degradation, holds great therapeutic potential. RESULTS: In this study, we developed an innovative therapeutic approach for OA using a combination of liposome-encapsulated siMMP13 and NG-Monomethyl-L-arginine Acetate (L-NMMA) to form an injectable hydrogel. The hydrogel served as a delivery vehicle for the siMMP13, allowing for sustained release and targeted delivery to the affected joint. Experiments conducted on destabilization of the medial meniscus (DMM) model mice demonstrated the therapeutic efficacy of this composite hydrogel. Treatment with the hydrogel significantly inhibited the degradation of cartilage matrix, as evidenced by histological analysis showing preserved cartilage structure and reduced loss of proteoglycans. Moreover, the hydrogel effectively suppressed intracellular ROS accumulation in chondrocytes, indicating its anti-oxidative properties. Furthermore, it attenuated chondrocyte apoptosis, as demonstrated by decreased levels of apoptotic markers. CONCLUSION: In summary, the injectable hydrogel containing siMMP13, endowed with anti-ROS and anti-apoptotic properties, may represent an effective therapeutic strategy for osteoarthritis in the future.
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Apoptosis , Condrocitos , Hidrogeles , Metaloproteinasa 13 de la Matriz , Osteoartritis , Especies Reactivas de Oxígeno , Animales , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Osteoartritis/patología , Especies Reactivas de Oxígeno/metabolismo , Apoptosis/efectos de los fármacos , Hidrogeles/química , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , Condrocitos/metabolismo , Condrocitos/efectos de los fármacos , Ratones Endogámicos C57BL , Masculino , Cartílago Articular/metabolismo , Cartílago Articular/efectos de los fármacos , Cartílago Articular/patología , Liposomas/química , HumanosRESUMEN
Lipid metabolism plays a crucial role in maintaining bone homeostasis, particularly in osteoclasts (OCs) formation. Here, we found that the expression level of FATP2, a transporter for long-chain and very-long-chain fatty acids, was significantly upregulated during OC differentiation and in the bone marrow of mice fed a high-fat diet (HFD). Notably, the use of FATP2 siRNA or a specific inhibitor (Lipofermata) resulted in significant inhibition of OC differentiation, while only slightly affecting osteoblasts. In pathological models of bone loss induced by LPS or ovariectomy, in vivo treatment with Lipofermata was able to rescue the loss of bone mass by inhibiting OC differentiation. RNA sequencing revealed that Lipofermata reduced fatty acid ß-oxidation and inhibited energy metabolism, while regulating ROS metabolism to decrease ROS production, ultimately inhibiting OC differentiation. Treatment with Lipofermata, either in vivo or in vitro, effectively rescued the overactivation of OCs, indicating that FATP2 regulated OC differentiation by modulating fatty acid uptake and energy metabolism. These findings suggested that targeting FATP2 may represent a promising therapeutic approach for pathological osteoporosis.
The inhibition of osteoclastogenesis by Lipofermata, a FATP2 inhibitor, was achieved through the reprogramming of energy metabolism and regulation of ROS levels. In both pathological bone loss and HFD-induced osteoporosis models, the expression levels of FATP2 were significantly upregulated, and Lipofermata demonstrated potential therapeutic effects in the pathological bone loss model.
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Diferenciación Celular , Metabolismo de los Lípidos , Osteoclastos , Osteogénesis , Especies Reactivas de Oxígeno , Animales , Metabolismo de los Lípidos/efectos de los fármacos , Osteoclastos/metabolismo , Ratones , Osteogénesis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Diferenciación Celular/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Proteínas de Transporte de Ácidos Grasos/metabolismo , Proteínas de Transporte de Ácidos Grasos/genética , Dieta Alta en GrasaRESUMEN
The transformation induced plasticity phenomenon occurs when one phase transforms to another one during plastic deformation, which is usually diffusionless. Here we present elemental partitioning-mediated crystalline-to-amorphous phase transformation during quasi-static plastic deformation, in an alloy in form of a Cr-Ni-Co (crystalline)/Zr-Ti-Nb-Hf-Ni-Co (amorphous) nanolaminated composite, where the constitute elements of the two phases have large negative mixing enthalpy. Upon plastic deformation, atomic intermixing occurs between adjacent amorphous and crystalline phases due to extensive rearrangement of atoms at the interfaces. The large negative mixing enthalpy among the constituent elements promotes amorphous phase transformation of the original crystalline phase, which shows different composition and short-range-order structure compared with the other amorphous phase. The reduced size of the crystalline phase shortens mean-free-path of dislocations, facilitating strain hardening. The enthalpy-guided alloy design based on crystalline-to-amorphous phase transformation opens up an avenue for the development of crystal-glass composite alloys with ultrahigh strength and large plasticity.
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BACKGROUND: Although cervical intervertebral disc (IVD) degeneration is closely associated with neck pain, its cause remains unclear. In this study, an animal model of cervical disc degeneration and discogenic neck pain induced by a low concentration of Propionibacterium acnes (P. acnes-L) is investigated to explore the possible mechanisms of cervical discogenic pain. METHODS: Cervical IVD degeneration and discitis was induced in 8-week-old male rats in C3-C6 IVDs through the anterior intervertebral puncture with intradiscal injections of low and high concentrations of P. acnes (P. acnes-L, n = 20 and P. acnes-H, n = 15) or Staphylococcus aureus (S. aureus, n = 15), compared to control (injection with PBS, n = 20). The structural changes in the cervical IVD using micro-CT, histological evaluation, and gene expression assays after MRI scans at 2 and 6 weeks post-modeling. The P. acnes-L induced IVD degeneration model was assessed for cervical spine MRI, histological degeneration, pain-like behaviors (guarding behavior and forepaw von Frey), nerve fiber growth in the IVD endplate region, and DRG TNF-α and CGRP. RESULTS: IVD injection with P. acnes-L induced IVD degeneration with decreased IVD height and MRI T2 values. IVD injection with P. acnes-H and S. aureus both lead to discitis-like changes on T2-weighted MRI, trabecular bone remodeling on micro-CT, and osseous fusion after damage in the cartilage endplate adjacent to the injected IVD. Eventually, rats in the P. acnes-L group exhibited significant nociceptive hypersensitivity, nerve fiber ingrowth was observed in the IVD endplate region, inflammatory activity in the DRG was significantly increased compared to the control group, and the expression of the pain neurotransmitter CGRP was significantly upregulated. CONCLUSION: P. acnes-L was validated to induce cervical IVD degeneration and discogenic pain phenotype, while P. acnes-H induced was identified to resemble septic discitis comparable to those caused by S. aureus infection.
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Discitis , Degeneración del Disco Intervertebral , Disco Intervertebral , Masculino , Ratas , Animales , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/metabolismo , Propionibacterium acnes/metabolismo , Discitis/metabolismo , Discitis/patología , Dolor de Cuello/metabolismo , Dolor de Cuello/patología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Staphylococcus aureus , Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/metabolismo , Modelos Animales de EnfermedadRESUMEN
Hepatocellular carcinoma (HCC) is one of the most common malignancies and the third leading cause of cancer-related deaths globally. Hepatic arterial infusion chemotherapy (HAIC) treatment is widely accepted as one of the alternative therapeutic modalities for HCC owing to its local control effect and low systemic toxicity. Nevertheless, although accumulating high-quality evidence has displayed the superior survival advantages of HAIC of oxaliplatin, fluorouracil, and leucovorin (HAIC-FOLFOX) compared with standard first-line treatment in different scenarios, the lack of standardization for HAIC procedure and remained controversy limited the proper and safe performance of HAIC treatment in HCC. Therefore, an expert consensus conference was held on March 2023 in Guangzhou, China to review current practices regarding HAIC treatment in patients with HCC and develop widely accepted statements and recommendations. In this article, the latest evidence of HAIC was systematically summarized and the final 22 expert recommendations were proposed, which incorporate the assessment of candidates for HAIC treatment, procedural technique details, therapeutic outcomes, the HAIC-related complications and corresponding treatments, and therapeutic scheme management.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Resultado del Tratamiento , Arteria Hepática/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fluorouracilo/uso terapéutico , Infusiones IntraarterialesRESUMEN
Due to their complex genotypes, low in vitro regeneration rates, and difficulty in obtaining transgenic plants, studies concerning basic biological research and molecular breeding in Tartary buckwheat (TB) are greatly limited. In this study, the hypocotyls of 60 genotypes of TB (TBC1~60) were used as explants. Of these, TBC14 was selected due to a high callus induction rate of 97.78% under dark and a proliferation coefficient (PC) of 28.2 when cultured on MS medium supplemented with 2.0 mg/L of 2,4-D and 1.5 mg/L of 6-BA. Subsequently, the samples of the calli obtained from TBC14 were collected at 0, 10, 20, and 30 d, and their transcriptomes were sequenced where identified. GO enrichment led to the detection of the most significant active gene set, which was the DNA binding transcription factor activity. The DEGs related to the pathways concerning metabolism, the biosynthesis of secondary metabolites, and hormone signal transduction were the most enriched in the KEGG database. The sets of MYB, AP2/ERF, and bHLH TFs exhibited the highest number of DEGs. Using this enrichment analysis, 421 genes encoding TFs, 47 auxin- and cytokinin-related genes, and 6 signal transduction-associated genes were screened that may play significant roles in callus formation (CF) in TB. Furthermore, FtPinG0008123200.01 (bZIP), a key gene promoting CF, was screened in terms of the weighted gene co-expression network associated with the various stages of CF. Our study not only provides valuable information about the molecular mechanism of CF but also reveals new genes involved in this process.
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OBJECTIVES: This paper aims to explore the successful implementation of online postgraduate admissions re-examination in China, specifically focusing on the Modified Objective Structured Examination (MOSE). It introduced the specific practice of the online postgraduate admissions re-examination in China and investigated the perceptions of applicants, postgraduate supervisors and admissions staffs about the online MOSE re-examination. METHODS: Surveys were administrated 3 years after the implementation of online MOSE postgraduate admissions re-examination in China. Separate surveys were conducted with applicants, postgraduate supervisors, and admissions staff members to gather their opinions and suggestions regarding the online MOSE re-examination. RESULTS: A total of 65 applicants, 43 postgraduate supervisors and seven admissions staff members completed the surveys. Over 80% of the applicants agreed that the online MOSE comprehensively evaluated their medical humanities, communication, medical knowledge, and overall competence. Furthermore, 89.30% of postgraduate supervisors believed that the students recruited through online MOSE were either "not significantly different," "better," or "much better" compared to those recruited through on-site re-examination. Admissions staff members also expressed a favorable view of online MOSE re-examination. CONCLUSION: The online MOSE re-examination is an effective, convenient, and affirmative evaluation method for postgraduate admissions re-examination.
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Humanidades , Estudiantes , Humanos , Universidades , China , Encuestas y CuestionariosRESUMEN
OBJECTIVE: This research aimed to evaluate the influence of Modic changes (MCs) on disc degeneration at the same and adjacent cephalad levels in the cervical spine. METHODS: This research retrospectively reviewed 1036 patients with neck pain, upper limb pain, or numbness who were treated at our out-patient clinic and underwent cervical MRI and cervical anteroposterior/lateral radiography from Jan, 2016 to Jan, 2021. MCs and disc degeneration parameters at same and nearby cephalad levels of MCs were evaluated. Discs were divided into the MCs, adjacent, and control groups, and the association between MCs and disc degeneration at the same and adjacent cephalad levels was investigated. RESULTS: Of the 1036 patients whose MRI scans were reviewed, 986 met the inclusion criteria (503 women and 483 men; average age, 62.8 years; scope of 35-79 years). The prevalence of MCs in the cervical spine was 13.0% (128/986). Type I, II, III changes were observed in 38 (29.69%), 82 (64.06%), and 8 (6.25%) patients, respectively. MCs were most frequently identified at the C5-6 (59/986; 5.98%) and C6-7 (38/986; 3.85%) levels. Disc with MCs showed worse outcomes with regard to disc degeneration grade, anterior osteophyte formation than the adjacent and control groups (p < 0.05), whereas they were more severe in the adjacent group compared to normal group. CONCLUSION: Our findings indicate that MCs increased disc degeneration at the same and nearby cephalad levels in cervical spine, and the severity of degeneration at the same segment was more serious than that at the cephalad level.
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Degeneración del Disco Intervertebral , Masculino , Humanos , Femenino , Persona de Mediana Edad , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/epidemiología , Estudios Retrospectivos , Vértebras Cervicales/diagnóstico por imagen , Dolor de Cuello , Imagen por Resonancia MagnéticaRESUMEN
AIM: Although lipoproteins are well-established risk factors for cardiovascular disease (CVD) mortality, conventional measurements failed to identify lipoprotein particle sizes. This study aimed to investigate associations of lipoprotein subclasses categorized by particle sizes with risk of all-cause and CVD mortality in individuals with type 2 diabetes. METHODS: This study included 6575 individuals with type 2 diabetes from the UK Biobank. Concentrations of very low-, low-, intermediate- and high-density lipoprotein [very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), intermediate-density lipoprotein and high-density lipoprotein (HDL)] particles in 14 subclasses and lipid constituents within each subclass were measured by quantitative nuclear magnetic resonance. Multivariable-adjusted Cox proportional-hazard regression models were used to estimate the hazard ratio (HR) for per standard deviation increment of log-transformed lipoprotein subclasses with risk of mortality. All p-values were adjusted by the false discovery rate method. RESULTS: During a median follow-up of 11.4 years, 943 deaths were documented, including 310 CVD deaths. Small HDL particles were inversely associated with CVD mortality, with HR (95% CI) of 0.78 (0.69, 0.87), whereas very large and large HDL particles were positively associated with CVD mortality with HR (95% CI) of 1.28 (1.12, 1.45) and 1.19 (1.05, 1.35), respectively. A similar pattern was observed for all-cause mortality [small HDL particle (HR, 95% CI): 0.79, 0.74-0.85; large HDL particle: 1.15, 1.07-1.24; very large HDL particle: 1.26, 1.17-1.36]. For VLDL and LDL, very small VLDL particle was positively, while medium LDL particle was inversely associated with all-cause mortality, but not associated with CVD mortality. The pattern of association with all-cause and CVD mortality for cholesterol and triglyceride within lipoprotein particles was similar to those for lipoprotein particles themselves. CONCLUSIONS: The associations between lipoprotein particles, particularly HDL particles, with all-cause and CVD mortality among patients with type 2 diabetes were significantly varied by particle sizes, highlighting the importance of particle size as a lipoprotein metric in mortality risk discrimination.
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Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Enfermedades Cardiovasculares/complicaciones , Estudios Prospectivos , Lipoproteínas , Lipoproteínas HDL , Lipoproteínas VLDL , Factores de Riesgo , HDL-ColesterolRESUMEN
To alleviate the mechanical instability of major shear bands in metallic glasses at room temperature, topologically heterogeneous structures were introduced to encourage the multiplication of mild shear bands. Different from the former attention on topological structures, here we present a compositional design approach to build nanoscale chemical heterogeneity to enhance homogeneous plastic flow upon both compression and tension. The idea is realized in a Ti-Zr-Nb-Si-XX/Mg-Zn-Ca-YY hierarchically nanodomained amorphous alloy, where XX and YY denote other elements. The alloy shows ~2% elastic strain and undergoes highly homogeneous plastic flow of ~40% strain (with strain hardening) in compression, surpassing those of mono- and hetero-structured metallic glasses. Furthermore, dynamic atomic intermixing occurs between the nanodomains during plastic flow, preventing possible interface failure. Our design of chemically distinct nanodomains and the dynamic atomic intermixing at the interface opens up an avenue for the development of amorphous materials with ultrahigh strength and large plasticity.
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Thoracic ossification of the ligamentum flavum (TOLF) is a common cause of progressive thoracic myelopathy. TOLF is typically treated with surgical decompression. A variety of surgical techniques, including laminoplasty, laminectomy, and lamina fenestration, are used for the effective treatment of TOLF. However, traditional methods are associated with a substantial risk of perioperative complications, including dural laceration and/or iatrogenic spinal cord injury. Therefore, it is important to develop an efficient and secure surgical technique for TOLF. Herein, we describe a method for laminectomyperformed at the thoracic spine using an ultrasonic osteotome combined with a conventional osteotome. This technique can reduce intraoperative complications. This is a relatively safe and easy-to-learn method that should be recommended for the treatment of TOLF.
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Ligamento Amarillo , Osificación Heterotópica , Humanos , Laminectomía , Osteogénesis , Osificación Heterotópica/diagnóstico por imagen , Osificación Heterotópica/cirugía , Osificación Heterotópica/complicaciones , Ligamento Amarillo/diagnóstico por imagen , Ligamento Amarillo/cirugía , Ultrasonido , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/cirugía , Resultado del Tratamiento , Estudios RetrospectivosRESUMEN
Focused ultrasound (FUS) has the potential to modulate regional brain excitability and possibly aid seizure control; however, effects on behavior of FUS used as a seizure therapy are unknown. This study explores behavioral effects and hippocampal restoration induced by pulsed FUS in a kainic acid (KA) animal model of temporal lobe epilepsy. Twenty-nine male Sprague-Dawley rats were observed for 20 weeks with anatomical magnetic resonance imaging (MRI) and behavioral performance evaluations, comprising measures of anxiety, limb usage, sociability, and memory. FUS targeted to the right hippocampus was given 9 and 14 weeks after KA was delivered to the right amygdala. Ultrasound pulsations were delivered with the acoustic settings of 0.25 of mechanical index, 0.5 W/cm2 of intensity spatial peak temporal average (ISPTA), 100 Hz of pulse repetition frequency, and 30% of duty cycle, during three consecutive pulse trains of 10 min separated by 5-min rests. Controls included normal animals with sham injections and KA-exposed animals without FUS exposure. Longitudinal MRI observations showed that FUS substantially protected hippocampal and striatal structures from KA-induced atrophy. KA alone increased anxiety, impaired contralateral limb usage, and reduced sociability and learning. Two courses of FUS sonications partially ameliorated these impairments by enhancing exploring and learning, balancing limb usage, and increasing social interaction. The histology results indicated that two sonications enhanced neuroprotection effect and decreased the inflammation markers induced by KA. This study supports existence of both neuroprotective and beneficial behavioral effects from low-intensity pulsed ultrasound in the KA animal model of epilepsy.
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Epilepsia , Ácido Kaínico , Ratas , Masculino , Animales , Ácido Kaínico/toxicidad , Ratas Sprague-Dawley , Hipocampo , Epilepsia/inducido químicamente , Epilepsia/diagnóstico por imagen , Epilepsia/terapia , Convulsiones , Modelos Animales de EnfermedadRESUMEN
There is considerable potential for integrating transarterial chemoembolization (TACE), programmed death-(ligand)1 (PD-[L]1) inhibitors, and molecular targeted treatments (MTT) in hepatocellular carcinoma (HCC). It is necessary to investigate the therapeutic efficacy and safety of TACE combined with PD-(L)1 inhibitors and MTT in real-world situations. In this nationwide, retrospective, cohort study, 826 HCC patients receiving either TACE plus PD-(L)1 blockades and MTT (combination group, n = 376) or TACE monotherapy (monotherapy group, n = 450) were included from January 2018 to May 2021. The primary endpoint was progression-free survival (PFS) according to modified RECIST. The secondary outcomes included overall survival (OS), objective response rate (ORR), and safety. We performed propensity score matching approaches to reduce bias between two groups. After matching, 228 pairs were included with a predominantly advanced disease population. Median PFS in combination group was 9.5 months (95% confidence interval [CI], 8.4-11.0) versus 8.0 months (95% CI, 6.6-9.5) (adjusted hazard ratio [HR], 0.70, P = 0.002). OS and ORR were also significantly higher in combination group (median OS, 19.2 [16.1-27.3] vs. 15.7 months [13.0-20.2]; adjusted HR, 0.63, P = 0.001; ORR, 60.1% vs. 32.0%; P < 0.001). Grade 3/4 adverse events were observed at a rate of 15.8% and 7.5% in combination and monotherapy groups, respectively. Our results suggest that TACE plus PD-(L)1 blockades and MTT could significantly improve PFS, OS, and ORR versus TACE monotherapy for Chinese patients with predominantly advanced HCC in real-world practice, with an acceptable safety profile.
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Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Quimioembolización Terapéutica/efectos adversos , Quimioembolización Terapéutica/métodos , Estudios de Cohortes , Neoplasias Hepáticas/patología , Terapia Molecular Dirigida , Estudios RetrospectivosRESUMEN
STUDY DESIGN: Retrospective clinical case series. OBJECTIVES: To investigate the risk factors for intraoperative endplate violations and delayed cage subsidence after oblique lateral interbody fusion (OLIF) surgery. Secondly, to examine whether low Hounsfield unit (HU) values at different regions of the endplate are associated with intraoperative endplate violation or delayed cage subsidence. METHODS: 61 patients (aged 65.1 ± 9.5 years; 107 segments) who underwent OLIF with or without posterior instrumentation from May 2015 to April 2019 were retrospectively studied. Intraoperative endplate violation was measured on sagittal reconstructed computerized tomography (CT) images immediate postoperatively, while delayed cage subsidence was evaluated using lateral radiographs and defined at 1-month follow-up or later. Demographic information and clinical parameters such as age, body mass index, bone mineral density, number of surgical levels, cage dimension, disc height restoration, visual analogue scale (VAS), and HU at different regions of the endplate were obtained. RESULTS: Total postoperative cage subsidence was identified in 45 surgical levels (42.0%) in 26 patients (42.6%) up till postoperative 1-year follow-up. Low HU value at the ipsilateral epiphyseal ring was an independent risk factor for intraoperative endplate violation (P = .008) with a cut-off value of 326.21 HUs. Low HU values at the central endplate had a significant correlation with delayed cage subsidence in stand-alone cases (P = .013) with a cut-off value of 296.42 HUs. VAS scores were not different at 1 week postoperatively in cases with or without intraoperative endplate violation (3.12 ± .73 vs 2.89 ± .72, P = .166) and showed no difference at 1 year with or without delayed cage subsidence (1.95 ± .60 vs 2.26 ± .85, P = .173). CONCLUSIONS: Intraoperative endplate violation and delayed cage subsidence are not uncommon with OLIF surgery. HUs of the endplate are good predictors for intraoperative endplate violation and cage subsidence since they can represent the regional bone quality of the endplate in contact with the implant. VAS improvements were not affected by intraoperative endplate violation or delayed cage subsidence at 1-year follow-up. LEVEL OF EVIDENCE: Level III.
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Intervertebral disc degeneration (IVDD) has been known as a highly prevalent and disabling disease, which is one of the main causes of low back pain and disability. Unfortunately, there is no effective cure to treat this formidable disease, and surgical interventions are typically applied. Herein, we report that the local administration of nitric oxide (NO)-releasing micellar nanoparticles can efficiently treat IVDD associated with Modic changes in a rat model established by infection with Cutibacterium acnes (C. acnes). By covalent incorporation of palladium(II) meso-tetraphenyltetrabenzoporphyrin photocatalyst and coumarin-based NO donors into the core of micellar nanoparticles, we demonstrate that the activation of the UV-absorbing coumarin-based NO donors can be achieved under red light irradiation via photoredox catalysis, although it remains a great challenge to implement photoredox catalysis reactions in biological conditions due to the complex microenvironments. Notably, the local delivery of NO can not only efficiently eradicate C. acnes pathogens but also inhibit the inflammatory response and osteoclast differentiation in the intervertebral disc tissues, exerting antibacterial, anti-inflammatory, and antiosteoclastogenesis effects. This work provides a feasible means to efficiently treat IVDD by the local administration of NO signaling molecules without resorting to a surgical approach.
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Acné Vulgar , Degeneración del Disco Intervertebral , Disco Intervertebral , Ratas , Animales , Degeneración del Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/microbiología , Óxido Nítrico/metabolismo , Disco Intervertebral/metabolismo , Disco Intervertebral/microbiología , Transducción de Señal , Acné Vulgar/complicaciones , Acné Vulgar/metabolismo , Propionibacterium acnesRESUMEN
BACKGROUND: Rheumatoid arthritis patients usually suffer from arthritic chronic pain. However, due to an incomplete understanding of the mechanisms underlying autoimmune disorders, the management of arthritic pain is unsatisfactory. Here, we investigated the analgesic effect and underlying mechanism of the natural flavonoid naringenin (NAR) in collagen-induced arthritis (CIA) pain. METHODS: NAR was injected (i.p.) once per day for 42 days after initial immunization, and rats were sacrificed on the 28th (the 21st day after final immunization, PID 21) and 42nd days (PID 35). The inflammatory factors, central sensitization indicators, and CRMP2 phosphorylation, as well as the anti-rheumatoid activity and analgesic effect of NAR, were further investigated. RESULTS: We found that NAR decreased the arthritis score and paw swelling, as well as the mechanical and thermal pain. The immunofluorescence results also showed a dose dependent effect of NAR on reducing the expressions of spinal cFos, IBA-1, and GFAP on the 28th (PID 21) and 42nd day (PID 35). NAR decreased the phosphorylation of CRMP2 S522 and the expression of the kinase CDK5 in the spinal dorsal horn, but pCRMP2 Y479 was unchanged. In addition, CRMP2 was co-localized with NEUN, but not IBA-1 or GFAP, indicating the involvement of neural CRMP2 phosphorylation in CIA-related pain. Finally, CRMP2 S522 phosphorylation selective inhibitor (S)-lacosamide also alleviated arthritic pain. CONCLUSIONS: Taken together, our results demonstrate that NAR alleviates inflammation and chronic pain in CIA model, which might be related to its inhibition of neuronal CRMP2 S522 phosphorylation, potentially mitigating the central sensitization. Our study provide evidence for the potential use of NAR as non-opioid-dependent analgesia in arthritic pain.
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Artritis Experimental , Artritis Reumatoide , Dolor Crónico , Ratas , Animales , Fosforilación , Flavonoides/farmacología , Artralgia , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , AnalgésicosRESUMEN
OBJECTIVE: 1) To investigate if implant-related factors such as cage size and cage position are associated with radiologic improvement after indirect decompression with oblique lateral interbody fusion (OLIF). 2) To investigate the risk factors associated with indirect decompression failure (IDF) at the surgical levels after OLIF. METHODS: From February 2015 to December 2019, 92 consecutive patients (188 levels) with lumbar spinal stenosis who underwent indirect decompression via OLIF with or without posterior instrumentation were studied retrospectively. Radiographic variables were measured preoperatively and postoperatively. The radiographic results were compared for cages with different heights and positions. IDF was defined as revision surgery within 6 months or persistent compressive symptoms 6 months after surgery. RESULTS: Postoperative improvements were observed in all measured radiographic parameters except for segmental lordosis. Taller cages were associated with more shrinkage of the bulging disc and greater increase in dural sac diameter. Cages placed posteriorly showed larger postoperative subarticular diameters. Twelve patients (16 levels) had IDF. Multivariate logistic regression showed that after adjusting for age, sex, and body mass index, smaller preoperative dural sac cross-sectional area and anterior positioning of cages were both independent risk factors for IDF. CONCLUSIONS: OLIF is an effective procedure for indirect decompression. To avoid reoperation for lumbar spinal stenosis, surgeons should aim to place the center of the cage at the posterior half of the lower endplate. Surgical levels with a preoperative dural sac cross-sectional area <44 mm2 may not be suitable for indirect decompression.
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Fusión Vertebral , Estenosis Espinal , Humanos , Estenosis Espinal/diagnóstico por imagen , Estenosis Espinal/cirugía , Estenosis Espinal/etiología , Estudios Retrospectivos , Descompresión Quirúrgica/métodos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Factores de Riesgo , Resultado del TratamientoRESUMEN
The aims of this study were to investigate the outcomes of low- and high-virulence bacterial cervical intervertebral discs (IVDs) infection and its association with cervical IVDs degeneration in rats. A total of 75 clean grade male rats were used to establish the corresponding animal models of low and high virulent bacterial cervical disc infection via an anterior cervical approach, with injection of Propionibacterium acnes (P. acnes) and Staphylococcus epidermidis (S. epidermidis) with a 29 G needle to cervical IVDs. Specimens were collected for evaluation of Blood routine (Blood-RT), histological staining, and gene expression assays after a magnetic resonance imaging (MRI) scan. There were no statistical differences in all groups in white blood cells (WBC) at 2 and 6 weeks postoperatively (P = 0.136). The highest percentage of neutrophils was found in the S. epidermidis group at 2 weeks postoperatively (P = 0.043). MRI and histology showed that at 6 weeks postoperatively, the puncture group and P. acnes group had similar disc degeneration. In the S. epidermidis group, the disc and subchondral bone structure had been destroyed and bony fusion had occurred after the discitis. The upregulation of pro-inflammatory factor expression had the strongest effect of S. epidermidis on the early stage, while the upregulation in the puncture and P. acnes groups was more persistent. P. acnes infection of the cervical IVDs can lead to degenerative changes, whereas S. epidermidis infection leads to the manifestation of septic discitis. The correlation between P. acnes infection and cervical IVDs degeneration found in clinical studies was confirmed.
Asunto(s)
Discitis , Infecciones por Bacterias Grampositivas , Degeneración del Disco Intervertebral , Disco Intervertebral , Animales , Discitis/complicaciones , Discitis/diagnóstico por imagen , Discitis/patología , Infecciones por Bacterias Grampositivas/complicaciones , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/patología , Disco Intervertebral/diagnóstico por imagen , Disco Intervertebral/microbiología , Disco Intervertebral/patología , Degeneración del Disco Intervertebral/diagnóstico por imagen , Masculino , Propionibacterium acnes/fisiología , Ratas , VirulenciaRESUMEN
Sigma-1 receptor (Sigmar1) is a specific chaperone located in the mitochondria-associated endoplasmic reticulum membrane (MAM) and plays a role in several physiological processes. However, the role of Sigmar1 in bone homeostasis remains unknown. Here, we show that mice lacking Sigmar1 exhibited severe osteoporosis in an ovariectomized model. In contrast, overexpression of Sigmar1 locally alleviated the osteoporosis phenotype. Treatment with Sigmar1 agonists impaired both human and mice osteoclast formation in vitro. Mechanistically, SERCA2 was identified to interact with Sigmar1 based on the immunoprecipitation-mass spectrum (IP-MS) and co-immunoprecipitation (co-IP) assays, and Q615 of SERCA2 was confirmed to be the critical residue for their binding. Furthermore, Sigmar1 promoted SERCA2 degradation through Hrd1/Sel1L-dependent ER-associated degradation (ERAD). Ubiquitination of SERCA2 at K460 and K541 was responsible for its proteasomal degradation. Consequently, inhibition of SERCA2 impeded Sigmar1 deficiency enhanced osteoclastogenesis. Moreover, we found that dimemorfan, an FDA-approved Sigmar1 agonist, effectively rescued bone mass in various established bone-loss models. In conclusion, Sigmar1 is a negative regulator of osteoclastogenesis, and activation of Sigmar1 by dimemorfan may be a potential treatment for osteoporosis in clinical practice.