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1.
BMC Endocr Disord ; 23(1): 42, 2023 Feb 16.
Article in English | MEDLINE | ID: mdl-36793008

ABSTRACT

BACKGROUND: Cushing disease (CD) arises due to a pituitary corticotroph adenoma, which is the most common cause of Cushing syndrome (CS). Bilateral inferior petrosal sinus sampling (BIPSS) is a safe method for differentiating CD from ectopic adrenocorticotropic hormone (ACTH)-dependent CS. Enhanced high-resolution magnetic resonance imaging (MRI) can localize tiny pituitary lesions. The aim of this study was to compare the preoperative diagnostic accuracy of BIPSS versus MRI for CD in CS patients. We performed a retrospective study of patients who underwent BIPSS and MRI between 2017 and 2021. Low- and high-dose dexamethasone suppression tests were performed. Blood samples were collected simultaneously from the right and left catheter and femoral vein before and after desmopressin stimulation. MRI images were obtained, and endoscopic endonasal transsphenoidal surgery (EETS) was performed in confirmed CD patients. Dominant sides of ACTH secretion during BIPSS and MRI were compared with surgical findings. RESULTS: Twenty-nine patients underwent BIPSS and MRI. CD was diagnosed in 28 patients, 27 of whom received EETS. Localizations of microadenomas by MRI and BIPSS agreed with the EETS findings in 96% and 93% of the cases, respectively. BIPSS and EETS were successfully performed on all patients. CONCLUSION: BIPSS was the most accurate method (gold standard) for establishing a preoperative diagnosis of pituitary-dependent CD and was more sensitive than MRI in diagnosing microadenoma. High-resolution MRI with enhancement had an advantage over BIPSS in microadenoma lateralization diagnostics. The combined use of MRI and BIPSS could improve the preoperative diagnosis accuracy in ACTH-dependent CS patients.


Subject(s)
Adenoma , Cushing Syndrome , Pituitary ACTH Hypersecretion , Pituitary Neoplasms , Humans , Adenoma/diagnostic imaging , Adenoma/surgery , Adrenocorticotropic Hormone , Cushing Syndrome/diagnosis , Magnetic Resonance Imaging , Petrosal Sinus Sampling/methods , Pituitary ACTH Hypersecretion/diagnostic imaging , Pituitary ACTH Hypersecretion/surgery , Pituitary Neoplasms/diagnostic imaging , Pituitary Neoplasms/surgery , Retrospective Studies
2.
Geriatr Orthop Surg Rehabil ; 15: 21514593241280912, 2024.
Article in English | MEDLINE | ID: mdl-39220251

ABSTRACT

Introduction: Non-attendance with scheduled postoperative follow-up visits remains a common issue in orthopaedic clinical research. The objective of this study was to identify the risk factors associated with loss to follow-up among elderly patients with hip-fracture postoperatively. Methods: A retrospective analysis of 1-year post-surgery was performed on patients aged over 60 years who underwent hip-fracture surgery from January 2017 to March 2019. Based on their completion of the appointed follow-up schedule, the patients were classified into 2 groups: the Loss to Follow-up (LTFU) Group and the Follow-up (FU) Group. Clinical outcomes were evaluated by Functional Recovery Score (FRS) questionnaires. Telephone interviews were conducted with patients lost to follow-up to determine the reasons for non-attendance. A comparative analysis of baseline characteristics between the 2 groups was implemented, with further exploration of statistical differences through logistic regression. Results: A total of 992 patients met the inclusion criteria were included in this study, of which 189 patients, accounting for 19.1%, were lost to follow-up 1 year postoperatively. The mean age of the patients in the LTFU Group was 82.0 years, significantly higher than the 76.0 years observed in the FU Group (P < 0.001). The FRS for the LTFU Group was marginally higher than that of the FU group (84.0 vs 81.0), with no significant difference (P = 0.060). Logistic regression analysis identified several significant predictors of noncompliance, including advanced age at surgery, femoral neck fracture, hip arthroplasty, long distance from residence to hospital, and the reliance on urban-rural public transportation for reaching the hospital. Conclusion: Postoperative follow-up loss was prevalent among elderly patients with hip fractures. Our study indicated a constellation of risk factors contributing to noncompliance, including advanced age, transportation difficulties, long travel distance, femoral neck fracture and hip arthroplasty surgery.

3.
Adv Healthc Mater ; : e2402596, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39252661

ABSTRACT

The healing of bone defects among diabetic patients presents a critical challenge due to the pathological microenvironment, characterized by hyperglycemia, excessive reactive oxygen species (ROS) production, and inflammation. Herein, multifunctional composite microspheres, termed GMAP are developed, using a microfluidic technique by incorporating Au@Pt nanoparticles (NPs) and GelMA hydrogel to modulate the diabetic microenvironment for promoting bone regeneration. The GMAP enables the sustained release of Au@Pt NPs, which function as bimetallic nanozymes with dual enzyme-like activities involving glucose oxidase and catalase. The synergistic effect allows for efficient glucose consumption and ROS elimination concurrently. Thus, the GMAP effectively protects the proliferation of bone marrow mesenchymal stem cells (BMSCs) under adverse high-glucose conditions. Furthermore, it also promotes the osteogenic differentiation and paracrine capabilities of BMSCs, and subsequently inhibits inflammation and enhances angiogenesis. In vivo diabetic rats bone defect model, it is demonstrated that GMAP microspheres significantly improve bone regeneration, as verified by micro-computed tomography and histological examinations. This study provides a novel strategy for bone regeneration by modulating the diabetic microenvironment, presenting a promising approach for addressing the complex challenges associated with bone healing in diabetic patients.

4.
Sci Adv ; 10(33): eado7249, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39151007

ABSTRACT

Ferroptosis, caused by disorders of iron metabolism, plays a critical role in various diseases, making the regulation of iron metabolism essential for tissue repair. In our analysis of degenerated intervertebral disc tissue, we observe a positive correlation between the concentration of extracellular iron ions (ex-iron) and the severity of ferroptosis in intervertebral disc degeneration (IVDD). Hence, inspired by magnets attracting metals, we combine polyether F127 diacrylate (FDA) with tannin (TA) to construct a magnetically attracting hydrogel (FDA-TA). This hydrogel demonstrates the capability to adsorb ex-iron and remodel the iron metabolism of cells. Furthermore, it exhibits good toughness and self-healing properties. Notably, it can activate the PI3K-AKT pathway to inhibit nuclear receptor coactivator 4-mediated ferritinophagy under ex-iron enrichment conditions. The curative effect and related mechanism are further confirmed in vivo. Consequently, on the basis of the pathological mechanism, a targeted hydrogel is designed to reshape iron metabolism, offering insights for tissue repair.


Subject(s)
Ferroptosis , Hydrogels , Iron , Iron/metabolism , Hydrogels/chemistry , Humans , Ferroptosis/drug effects , Animals , Tannins/chemistry , Tannins/pharmacology , Intervertebral Disc Degeneration/metabolism , Wound Healing/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Proto-Oncogene Proteins c-akt/metabolism
5.
J Mater Chem B ; 12(30): 7367-7383, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-38940905

ABSTRACT

The bone immune microenvironment can influence the occurrence and progression of bone defects. To date, research on promoting macrophage M2 polarization to improve bone injury repair has been insufficient. In this study, we designed an injectable poly(L-lactic acid) (PLLA) porous microsphere that forms calcium phosphate crystals on its surface by binding to melatonin, followed by bionanomimetic mineralization in vitro. The microsphere is injectable and degradable, and its release of melatonin (MT) and calcium phosphate (CaP) crystals promotes macrophage M2 polarization, reprogramming of macrophages, and enhanced osteogenesis. After LPS stimulation, the proportion of M2-polarized macrophages in the MS@CaP@MT group was 39.2 ± 2.7%, significantly higher than that in other groups (P < 0.05). Further, in the MS@CaP@MT group, rats exhibited bone mineral densities of 129.4 ± 12.8 mg cc-1 at 2 weeks and 171.6 ± 13.6 mg cc-1 at 4 weeks in the defect area, which were significantly higher than those in other groups (P < 0.05). Using an animal model of femoral condylar defects, we demonstrated that MT PLLA porous microspheres loaded with calcium phosphate crystals can improve the immune microenvironment and form a microsphere-centered osteogenesis model. This significantly accelerates bone defect repair and provides a potential strategy for bone defect treatment.


Subject(s)
Calcium Phosphates , Macrophages , Melatonin , Microspheres , Polyesters , Calcium Phosphates/chemistry , Animals , Melatonin/pharmacology , Melatonin/chemistry , Polyesters/chemistry , Porosity , Rats , Mice , Macrophages/drug effects , Macrophages/metabolism , Rats, Sprague-Dawley , Bone Regeneration/drug effects , RAW 264.7 Cells , Male , Surface Properties , Particle Size , Osteogenesis/drug effects
6.
Phytomedicine ; 133: 155940, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39128303

ABSTRACT

BACKGROUND: Traumatic brain injury (TBI) could induce multiple forms of cell death, ferroptosis, a novel form of cell death distinct from apoptosis and autophagy, plays an important role in disease progression in TBI. Therapies targeting ferroptosis are beneficial for recovery from TBI. Paeoniflorin (Pae) is a water-soluble monoterpene glycoside and the active ingredient of Paeonia lactiflora pall. It has been shown to exert anti-inflammatory and antioxidant effects. However The effects and mechanisms of paeoniflorin on secondary injury after TBI are unknown. PURPOSE: To investigate the mechanism by which Pae regulates ferroptosis after TBI. METHODS: The TBI mouse model and cortical primary neurons were utilized to study the protective effect of paeoniflorin on the brain tissue after TBI. The neuronal cell ferroptosis model was established by treating cortical primary neurons with erastin. Liproxstatin-1(Lip-1) was used as a positive control drug. Immunofluorescence staining, Nissl staining, biochemical analyses, pharmacological analyses, and western blot were used to evaluate the effects of paeoniflorin on TBI. RESULTS: Pae significantly ameliorated neuronal damage after TBI, inhibited mitochondrial damage, increased glutathione peroxidase 4 (GPX4) activity, decreased malondialdehyde (MDA) production, restored neurological function and inhibited cerebral edema. Pae promotes the degradation of P53 in the form of proteasome, promotes its ubiquitination, and reduces the stability of P53 by inhibiting its acetylation, thus alleviating the P53-mediated inhibition of cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11) by P53. CONCLUSION: Pae inhibits ferroptosis by promoting P53 ubiquitination out of the nucleus, inhibiting P53 acetylation, and modulating the SLC7A11-GPX4 pathway.


Subject(s)
Brain Injuries, Traumatic , Ferroptosis , Glucosides , Monoterpenes , Tumor Suppressor Protein p53 , Glucosides/pharmacology , Ferroptosis/drug effects , Brain Injuries, Traumatic/drug therapy , Brain Injuries, Traumatic/metabolism , Animals , Monoterpenes/pharmacology , Tumor Suppressor Protein p53/metabolism , Acetylation , Mice , Male , Neurons/drug effects , Disease Models, Animal , Mice, Inbred C57BL , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Paeonia/chemistry , Neuroprotective Agents/pharmacology
7.
Front Oncol ; 13: 1121140, 2023.
Article in English | MEDLINE | ID: mdl-36874111

ABSTRACT

Background: Thyroid-stimulating hormone (TSH)-secreting pituitary adenomas (TSHomas) are rare and usually present with hyperthyroidism. Calcification in pituitary tumors is an infrequent finding. Herein, we report an extremely rare case of TSHoma with diffuse calcification. Case description: A 43-year-old man was admitted to our department with a complaint of palpitations. An endocrinological examination revealed elevated serum levels of TSH, free triiodothyronine (FT3), and free thyroxin, whereas the physical examination revealed no obvious abnormality. Computerized tomography (CT) showed a sellar mass with diffuse calcification. Contrast-enhanced T1-weighted images revealed a less-enhancing tumor without obvious suprasellar or parasellar expansion. The tumor was completely removed via endoscopic transnasal-sphenoidal surgery. Microscopically, nests of cells were inconspicuous among the diffuse psammoma bodies. Expression of TSH was patchy, and only several TSH-positive cells were observed. Postoperatively, the serum levels of TSH, FT3, and FT4 decreased to their normal range. Follow-up MR images showed no evidence of residual tumor or regrowth after the resection. Conclusions: Herein, we report a rare case of TSHoma with diffuse calcification that presented with hyperthyroidism. A correct and early diagnosis was made according to the European Thyroid Association guidelines. This tumor was completely removed via endoscopic transnasal-transsphenoidal surgery (eTSS), and thyroid function was normalized after the operation.

8.
Front Oncol ; 13: 1191399, 2023.
Article in English | MEDLINE | ID: mdl-37916174

ABSTRACT

Objective: The objective of this study was to investigate the clinical experience and therapeutic efficiency of Endoport-assisted neuroendoscopic surgery for resection of lateral ventricular tumors. The key points and application value of this surgical technique were additionally discussed. Methods: A retrospective analysis was conducted on the clinical and follow-up data of 16 patients who underwent endoport-assisted neuroendoscopic surgery for lateral ventricular tumors at the Department of Neurosurgery, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, between January 2018 and September 2020. The surgical procedures, complications and outcomes were analyzed. Results: The study included a total of 16 patients (5 males and 11 females) with lateral ventricular tumors, with a mean age of 43.2 years (18-70 years old). The tumors were distributed as follows: 5 cases involved the body of the lateral ventricle, 3 involved the frontal horn and body, 3 involved the occipital horn, 2 involved the trigone, 2 involved the frontal horn, and 1 case involved the occipital horn and body. Perioperative complications were analyzed, revealing 1 case of intraoperative acute epidural hematoma intraoperative and 2 cases of postoperative obstructive hydrocephalus. All complications were promptly managed. Postoperative MRI revealed that 14 cases (88%) achieved total resection, while 2 cases (12%) achieved subtotal resection. During the follow-up of 6-38 months, no recurrence was observed. The patient diagnosed with glioblastoma died 16 months after surgery (GOS=1), while the remaining patients have successfully resumed to normal daily life with a GOS score of 5. Conclusion: In conclusion, endoport-assisted neuroendoscopic surgery proved to be a minimally invasive and effective technique for resecting lateral ventricular tumors, with acceptable complications. It effectively utilizes the benefits of close observation, comprehensive exposure, and reduced tissue damage. Therefore, endoport-assisted neuroendoscopic surgery is suitable for the resection of lateral ventricular tumors.

9.
Transl Stroke Res ; 2023 Dec 26.
Article in English | MEDLINE | ID: mdl-38147294

ABSTRACT

Subarachnoid hemorrhage (SAH) is a type of stroke with a high disability and mortality rate. Apoptosis caused by massive damage to mitochondria in neuron cells and inflammatory responses caused by high extracellular ATP lead to poor outcomes. USP30 is a deubiquitinating enzyme that inhibits mitophagy, resulting in a failure to remove damaged mitochondria in a timely manner after SAH; nevertheless, the pathway through which USP30 inhibits mitophagy is unknown. This study evaluated the neuroprotective role and possible molecular basis by which inhibiting USP30 to attenuate SAH-induced EBI by promoting neuronal mitophagy. We used an in vitro model of hemoglobin exposure and an in vivo model of intravascular perforation. Increased expression of USP30 was found after SAH in vivo and in vitro, and USP30 inhibition expression in SAH mice treated with MF094 resulted in significant improvement of neurological injury and inflammatory response and mediated good outcomes, suggesting a neuroprotective effect of USP30 inhibition. In cultured neurons, inhibition of USP30 promoted ubiquitination modification of mitochondrial fusion protein 2 (MFN2) by E3 ubiquitin ligase (Parkin), separating damaged mitochondria from the healthy mitochondrial network and prompting mitophagy, causing early clearance of damaged intracellular mitochondria, and reducing the onset of apoptosis. The high extracellular ATP environment was meliorated, reversing the conversion of microglia to a pro-inflammatory phenotype and reducing inflammatory injury. USP30 inhibition had no autophagy-promoting effect on structurally and functionally sound mitochondria and did not inhibit normal intracellular ATP production. The findings suggest that USP30 inhibition has a neuroprotective effect after SAH by promoting early mitophagy after SAH to clear damaged mitochondria.

10.
Brain Behav ; 12(8): e2686, 2022 08.
Article in English | MEDLINE | ID: mdl-35803901

ABSTRACT

BACKGROUND: Traumatic brain injury (TBI) is the leading cause of death and disability worldwide. Mild hypothermia (32-35°C) has been found to show neuroprotective effects against TBI. However, the specific mechanism is still elusive. In the current study, we explored the relationship between oxidative damage after TBI and treatment with mild hypothermia as well as the underlying molecular mechanisms. METHODS: We used the closed cortex injury model to perform the brain injury and a temperature monitoring and control system to regulate the body temperature of mice after injury. Adult male C57BL/6 mice were adopted in this study and divided into four experimental groups. Tissue samples were harvested 24 h after injury. RESULTS: First, our results showed that treatment with mild hypothermia significantly improved neurobehavioral dysfunction and alleviated brain edema after TBI. Moreover, treatment with mild hypothermia enhanced the activity of the antioxidant enzymes superoxide dismutase and glutathione peroxidase and reduced the accumulation of lipid peroxidation malondialdehyde. Importantly, the expression and activation of the nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) pathway were upregulated by mild hypothermia after TBI. Finally, treatment with hypothermia significantly decreased the cell apoptosis induced by TBI. CONCLUSION: Our results showed that the protective effects of mild hypothermia after TBI may be achieved by the upregulation of the Nrf2-ARE pathway and revealed Nrf2 as a potentially important target to improve the prognosis of TBI.


Subject(s)
Brain Injuries, Traumatic , Hypothermia , Neuroprotection , Animals , Brain Injuries, Traumatic/metabolism , Brain Injuries, Traumatic/therapy , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL , NF-E2-Related Factor 2/metabolism , Signal Transduction
11.
Gen Thorac Cardiovasc Surg ; 70(5): 479-490, 2022 May.
Article in English | MEDLINE | ID: mdl-35044634

ABSTRACT

BACKGROUND: Esophageal cancer is a common worldwide disease with a higher mortality rate. Studies on esophageal cancer patients with bone metastasis are rare. Our study focused on the clinicopathological features of patients with bone metastasis using the Surveillance, Epidemiology and End Results (SEER) database to further explore the risk factors and survival for bone metastasis. METHODS: Esophageal cancer patients with bone metastasis were extracted from the SEER database. Univariable analysis and multivariable logistic regression were used to study the risk factors for bone metastasis. Univariable analysis and multivariable Cox regression were performed to reveal the survival and prognostic factors for bone metastasis. The competitive risk model was made to compare the association with bone metastasis among different causes of death. Propensity score matching was used to reduce the bias. RESULTS: Male, middle esophagus, with brain metastasis, without lung metastasis and without liver metastasis were major independent risk factors of bone metastasis. Older age, poorly differentiated and undifferentiated, with brain metastasis and with liver metastasis were major independent prognostic factors of bone metastasis. Patients with bone metastasis had a worse prognosis before and after propensity score matching than patients with other metastasis. CONCLUSIONS: Esophageal cancer patients with male sex, middle esophagus and brain metastasis were more likely to have bone metastasis. Compared to patients with other metastatic sites such as liver, brain and lung, patients with bone metastasis had a worse prognosis. Our findings provide recommendations about clinical guidelines for esophageal cancer patients with bone metastasis.


Subject(s)
Adenocarcinoma , Bone Neoplasms , Brain Neoplasms , Carcinoma, Squamous Cell , Esophageal Neoplasms , Liver Neoplasms , Bone Neoplasms/secondary , Brain Neoplasms/epidemiology , Brain Neoplasms/secondary , Esophageal Neoplasms/pathology , Humans , Liver Neoplasms/secondary , Male , Prognosis , SEER Program
12.
Front Bioeng Biotechnol ; 10: 927050, 2022.
Article in English | MEDLINE | ID: mdl-35935476

ABSTRACT

The regeneration of critical-size bone defects on long bones has remained a significant challenge because of the complex anatomical structure and vascular network. In such circumstances, current biomaterial forms with homogeneous structure and function can hardly satisfy the need for both osteogenesis and angiogenesis. In the current study, a heterogeneous biomimetic structured scaffold was constructed with the help of a 3D printed mold to simultaneously mimic the outer/inner periosteum and intermediate bone matrix of a natural long bone. Because of the reinforcement via modified mesoporous bioactive glass nanoparticles (MBGNs), enhanced structural stability and adequate osteogenic capacity could be achieved for the intermediate layer of this scaffold. Conversely, GelMA incorporated with VEGF-loaded liposome exhibiting controlled release of the angiogenic factor was applied to the inner and outer layers of the scaffold. The resulting heterogeneous structured scaffold was shown to successfully guide bone regeneration and restoration of the natural bone anatomic structure, rendering it a promising candidate for future orthopedic clinical studies.

13.
Front Endocrinol (Lausanne) ; 13: 1092431, 2022.
Article in English | MEDLINE | ID: mdl-36589857

ABSTRACT

The pathological condition of insulin resistance prevents the neuroprotective effects of insulin. Numerous studies have demonstrated that insulin resistance, as an independent risk factor for ischemic stroke, accelerates the formation of thrombosis and promotes the development of atherosclerosis, both of which are major mechanisms of ischemic stroke. Additionally, insulin resistance negatively affects the prognosis of patients with ischemic stroke regardless of whether the patient has diabetes, but the mechanisms are not well studied. We explored the association between insulin resistance and the primary mechanisms of brain injury in ischemic stroke (inflammation, oxidative stress, and neuronal damage), looking for potential causes of poor prognosis in patients with ischemic stroke due to insulin resistance. Furthermore, we summarize insulin resistance therapeutic approaches to propose new therapeutic directions for clinically improving prognosis in patients with ischemic stroke.


Subject(s)
Brain Ischemia , Diabetes Mellitus , Insulin Resistance , Ischemic Stroke , Stroke , Humans , Insulin Resistance/physiology , Stroke/etiology , Stroke/therapy , Ischemic Stroke/etiology , Brain Ischemia/complications
14.
ACS Appl Mater Interfaces ; 12(6): 6840-6851, 2020 Feb 12.
Article in English | MEDLINE | ID: mdl-31999085

ABSTRACT

Recombinant human bone morphogenetic protein-2 (rhBMP-2) and bioceramic are the widely used bioactive factors in treatment of bone defects, but these easily cause side effects because of uncontrollable local concentration. In this study, rhBMP-2 was grafted on the surface of mesoporous bioglass nanoparticles (MBGNs) with an amide bond and then photo-cross-linked together with methacrylate gelatin (GelMA); in this way, a GelMA/MBGNs-rhBMP-2 hydrogel membrane was fabricated to release rhBMP-2 in a controllable program during the early bone regeneration period and then release calcium and silicon ions to keep promoting osteogenesis instead of rhBMP-2 in a long term. In this way, rhBMP-2 can keep releasing for 4 weeks and then the ions keep releasing after 4 weeks; this process is matched to early and late osteogenesis procedures. In vitro study demonstrated that the early release of rhBMP-2 can effectively promote local cell osteogenic differentiation in a short period, and then, the inorganic ions can promote cell adhesion not only in the early stage but also keep promoting osteogenic differentiation for a long period. Finally, the GelMA/MBGNs-rhBMP-2 hydrogel shows a superior capacity in long-term osteogenesis and promoting bone tissue regeneration in rat calvarial critical size defect. This GelMA/MBGNs-rhBMP-2 hydrogel demonstrated a promising strategy for the controllable and safer use of bioactive factors such as rhBMP-2 in artificial periosteum to accelerate bone repairing.


Subject(s)
Bone Morphogenetic Protein 2/administration & dosage , Calcium/administration & dosage , Craniofacial Abnormalities/drug therapy , Delayed-Action Preparations/administration & dosage , Drug Delivery Systems/methods , Periosteum/drug effects , Silicon/administration & dosage , Transforming Growth Factor beta/administration & dosage , Animals , Bone Morphogenetic Protein 2/chemistry , Bone Morphogenetic Protein 2/genetics , Bone Morphogenetic Protein 2/metabolism , Bone Regeneration/drug effects , Calcium/chemistry , Cell Adhesion/drug effects , Craniofacial Abnormalities/physiopathology , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/metabolism , Gelatin/chemistry , Humans , Hydrogels/chemistry , Nanoparticles/chemistry , Osteogenesis/drug effects , Periosteum/physiopathology , Rats , Rats, Sprague-Dawley , Recombinant Proteins/administration & dosage , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Silicon/chemistry , Transforming Growth Factor beta/chemistry , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/metabolism
15.
Biomaterials ; 227: 119555, 2020 01.
Article in English | MEDLINE | ID: mdl-31655445

ABSTRACT

The periosteum plays a vital role in both development and injury healing process of bone. However, few researches have focused on artificial periosteum, which was also limited by the complexity on its construction and biological risks for clinical practice. In order to tackle this issue, inspired by the structural development of periosteum, we put forward a hierarchical micro/nanofibrous bionic periosteum with sustained releasing of VEGF as exogenous vascularized fibrous layer of periosteum to induce endogenous cambium layer in vivo for complete regeneration of periosteal and bone tissue, through collagen self-assembly and micro-sol electrospinning technologies. The VEGF encapsulated in hyaluronan-PLLA core-shell structure was demonstrated to be released in a durable way for angiogenesis in fibrous layer and bone defect area. Meanwhile, the self-assembly of collagen together with electrospun fibers contributed to a hierarchical micro/nanostructure which greatly mimicked the microenvironment of extracellular matrix to provide structural and biochemical cues for cell adhesion, proliferation and differentiation, and lead to the formation of cambium layer which mimicked the in-situ ossification manner as intramembranous ossification. As the motif of this study, the periosteal regeneration was characterized both by osteoblasts and periostin, which represented structural and molecular mechanisms respectively. Furthermore, the periosteal biomaterial proposed here possessed the superior abilities of scar inhibition, angiogenesis, osteogenesis to repair the bone defect in a uniform and rapid manner by inherent periosteal ossific mechanism involved in both intramembranous and endochondral ossification. Thus, the endogenous-exogenous combined bionic periosteum proved to be efficient and versatile in triggering periosteal and bone regeneration and hopefully supply a promising strategy for solving clinical issue.


Subject(s)
Nanofibers , Vascular Endothelial Growth Factor A , Bone Regeneration , Delayed-Action Preparations , Drug Delivery Systems , Osteogenesis , Periosteum
16.
Front Neurosci ; 14: 557170, 2020.
Article in English | MEDLINE | ID: mdl-33281541

ABSTRACT

NLRP3 inflammasome has been considered as an important contributor to inflammation and neuronal death after traumatic brain injury (TBI). Oridonin (Ori), the major active ingredient of Chinese herbal medicine Rabdosia rubescens, has been proved to be a covalent NLRP3 inhibitor with strong anti-inflammation activity. The purpose of this study was to investigate the effect of Ori on inflammation and brain injury induced by TBI. Adult male C57BL/6 mice were subjected to closed-head injury using Hall's weight-dropping method. Ori was injected directly intraperitoneally at a dose of 10 mg/kg within 30 min after TBI and injected once daily until the experiments ended. Our results showed that NLRP3 inflammasome was activated within 24 h post-TBI. The expression of NLRP3 inflammasome components (NLRP3, ASC, and caspase-1) was significantly decreased after treatment with Ori. Besides, the secretion of IL-1ß and IL-18, downstream inflammatory factors of activated caspase-1, was reduced by Ori treatment. Importantly, Ori administration further protected the blood-brain barrier, alleviated brain edema, reduced cortical lesion volume, decreased cell death, and attenuated neurological deficits after TBI. Our findings indicate that NLRP3 inflammasome participated in the secondary injury after TBI and the application of Ori may provide neuroprotection via inhibiting NLRP3 inflammasome in animal models, suggesting that Ori might be a promising candidate for patients with TBI.

17.
Nanoscale ; 11(34): 15794-15803, 2019 Aug 29.
Article in English | MEDLINE | ID: mdl-31432854

ABSTRACT

Biomimetic scaffolds have been extensively studied for guiding osteogenesis through structural cues. Inspired by the natural bone growth process, we have employed a hierarchical outer-inner dual reinforcing strategy, which relies on the interfacial ionic bond interaction between amine/calcium and carboxyl groups, to build a nanofiber/particle dual strengthened hierarchical silk fibroin scaffold. This scaffold can provide an applicable form of osteogenic structural cue and mimic the natural bone forming process. Owing to the active interaction between compositions located in the outer pore space and the inner pore wall, the scaffold has over 4 times improvement in the mechanical properties, followed by a significant alteration of the cell-scaffold interaction pattern, demonstrated by over 2 times elevation in the spreading area and enhanced osteogenic activity potentially involving the activities of integrin, vinculin and Yes-associated protein (YAP). The in vivo performance of the scaffold identified the inherent osteogenic effect of the structural cue, which promotes rapid and uniform regeneration. Overall, the hierarchical scaffold is promising in promoting uniform bone regeneration through its specific structural cue endowed by its micro-nano construction.


Subject(s)
Biomimetic Materials/chemistry , Bone Regeneration , Fibroins/chemistry , Nanofibers/chemistry , Osteogenesis , Tissue Scaffolds/chemistry , Animals , Rats , Rats, Sprague-Dawley
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