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1.
Article in English | MEDLINE | ID: mdl-38697509

ABSTRACT

OBJECTIVE: People who sustain joint injuries such as anterior cruciate ligament (ACL) rupture often develop post-traumatic osteoarthritis (PTOA). In human patients, ACL injuries are often treated with ACL reconstruction. However, it is still unclear how effective joint restabilization is for reducing the progression of PTOA. The goal of this study was to determine how surgical restabilization of a mouse knee joint following non-invasive ACL injury affects PTOA progression. DESIGN: In this study, 187 mice were subjected to non-invasive ACL injury or no injury. After injury, mice underwent restabilization surgery, sham surgery, or no surgery. Mice were then euthanized on day 14 or day 49 after injury/surgery. Functional analyses were performed at multiple time points to assess voluntary movement, gait, and pain. Knees were analyzed ex vivo with micro-computed tomography, RT-PCR, and whole-joint histology to assess articular cartilage degeneration, synovitis, and osteophyte formation. RESULTS: Both ACL injury and surgery resulted in loss of epiphyseal trabecular bone (-27-32%) and reduced voluntary movement at early time points. Joint restabilization successfully lowered OA score (-78% relative to injured at day 14, p < 0.0001), and synovitis scores (-37% relative to injured at day 14, p = 0.042), and diminished the formation of chondrophytes/osteophytes (-97% relative to injured at day 14, p < 0.001, -78% at day 49, p < 0.001). CONCLUSIONS: This study confirmed that surgical knee restabilization was effective at reducing articular cartilage degeneration and diminishing chondrophyte/osteophyte formation after ACL injury in mice, suggesting that these processes are largely driven by joint instability in this mouse model. However, restabilization was not able to mitigate the early inflammatory response and the loss of epiphyseal trabecular bone, indicating that these processes are independent of joint instability.

2.
bioRxiv ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38766109

ABSTRACT

Objective: Anterior Cruciate Ligament (ACL) injury initiates post-traumatic osteoarthritis (PTOA) via two distinct processes: initial direct contact injury of the cartilage surface during ACL injury, and secondary joint instability due to the ACL deficiency. Using the well-established Compression-induced ACL rupture method (ACL-R) and a novel Non-Compression ACL-R model, we aimed to reveal the individual effects of cartilage compression and joint instability on PTOA progression after ACL injury in mice. Design: Twelve-week-old C57BL/6J male were randomly divided to three experimental groups: Compression ACL-R, Non-Compression ACL-R, and Intact. Following ACL injury, we performed joint laxity testing and microscopic analysis of the articular cartilage surface at 0 days, in vivo optical imaging of matrix-metalloproteinase (MMP) activity at 3 and 7 days, and histological and microCT analysis at 0, 7, 14, and 28 days. Results: The Compression ACL-R group exhibited a significant increase of cartilage roughness immediately after injury compared with the Non-Compression group. At 7 days, the Compression group exhibited increased MMP-induced fluorescence intensity and MMP-13 positive cell ratio of chondrocytes. Moreover, histological cartilage degeneration was observable in the Compression group at the same time point. Sclerosis of tibial subchondral bone in the Compression group was more significantly developed than in the Non-Compression group at 28 days. Conclusions: Both Compression and Non-Compression ACL injury initiated PTOA progression due to joint instability. However, joint contact during ACL rupture also caused initial micro-damage on the cartilage surface and initiated early MMP activity, which could accelerate PTOA progression compared to ACL injury without concurrent joint contact.

3.
J Vis Exp ; (199)2023 09 29.
Article in English | MEDLINE | ID: mdl-37843296

ABSTRACT

Traumatic joint injuries such as anterior cruciate ligament (ACL) rupture or meniscus tears commonly lead to post-traumatic osteoarthritis (PTOA) within 10-20 years following injury. Understanding the early biological processes initiated by joint injuries (e.g., inflammation, matrix metalloproteinases (MMPs), cathepsin proteases, bone resorption) is crucial for understanding the etiology of PTOA. However, there are few options for in vivo measurement of these biological processes, and the early biological responses may be confounded if invasive surgical techniques or injections are used to initiate OA. In our studies of PTOA, we have used commercially available near-infrared protease activatable probes combined with fluorescence reflectance imaging (FRI) to quantify protease activity in vivo following non-invasive compression-induced ACL injury in mice. This non-invasive ACL injury method closely recapitulates clinically relevant injury conditions and is completely aseptic since it does not involve disrupting the skin or the joint capsule. The combination of these injury and imaging methods allows us to study the time course of protease activity at multiple time points following a traumatic joint injury.


Subject(s)
Anterior Cruciate Ligament Injuries , Bone Resorption , Osteoarthritis , Mice , Animals , Anterior Cruciate Ligament Injuries/diagnostic imaging , Anterior Cruciate Ligament Injuries/complications , Anterior Cruciate Ligament/diagnostic imaging , Anterior Cruciate Ligament/surgery , Peptide Hydrolases
4.
J Biomech Eng ; 145(11)2023 11 01.
Article in English | MEDLINE | ID: mdl-37417814

ABSTRACT

Noninvasive compression-induced anterior cruciate ligament rupture (ACL-R) is an easy and reproducible model for studying post-traumatic osteoarthritis (PTOA) in mice. However, equipment typically used for ACL-R is expensive, immobile, and not available to all researchers. In this study, we compared PTOA progression in mice injured with a low-cost custom ACL-rupture device (CARD) to mice injured with a standard system (ElectroForce 3200). We quantified anterior-posterior (AP) joint laxity immediately following injury, epiphyseal trabecular bone microstructure, and osteophyte volume at 2 and 6 weeks post injury using micro-computed tomography, and osteoarthritis progression and synovitis at 2 and 6 weeks post injury using whole-joint histology. We observed no significant differences in outcomes in mice injured with the CARD system compared to mice injured with the Electroforce (ELF) system. However, AP joint laxity data and week 2 micro-CT and histology outcomes suggested that injuries may have been slightly more severe and PTOA progressed slightly faster in mice injured with the CARD system compared to the ELF system. Altogether, these data confirm that ACL-R can be successfully and reproducibly performed with the CARD system and that osteoarthritis (OA) progression is mostly comparable to that of mice injured with the ELF system, though potentially slightly faster. The CARD system is low cost and portable, and we are making the plans and instructions freely available to all interested investigators in the hopes that they will find this system useful for their studies of OA in mice.


Subject(s)
Anterior Cruciate Ligament Injuries , Joint Instability , Osteoarthritis , Mice , Animals , Anterior Cruciate Ligament Injuries/diagnostic imaging , X-Ray Microtomography , Osteoarthritis/diagnostic imaging
5.
J Clin Ultrasound ; 51(1): 203-209, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36165415

ABSTRACT

Horner Syndrome (HS) is characterized by symptoms of ipsilateral miosis, ptosis, enophthalmos, and facial anhidrosis, which is caused by the damaged oculosympathetic pathway. HS is rarely reported as postoperative complications of fine-needle aspiration (FNA). We report a case of HS triggered by Ultrasound-guided FNA during thyroid cancer management and conducted the literature review. A 31-year-old male with differentiated thyroid cancer underwent total thyroidectomy and regional lymph node dissection as well as radioactive iodine ablation, presented with persistently elevated tumor marker of thyroglobulin and suspicious left level IV and V cervical lymph nodes by neck ultrasound. Ultrasound-guided left cervical lymph nodes FNA for cellular diagnosis was performed, and typical manifestations of HS appeared immediately after the procedure. Subsequent ultrasound evaluation of the same area demonstrated a subtle strip of the hypo-echogenic area in the superior pole of the suspected level IV structure, suggesting sympathetic ganglia with the visible originating nerve fiber on the superior pole. All of the patient's symptoms of HS were resolved 2 months after the incidence. Cervical sympathetic ganglia can be similar in size, shape, and ultrasound characteristics to a malignant lymph node. Thorough ultrasound examination by directly comparing the potential ganglia with a typical malignant lymph node, and paying attention to any potential root fibers on the target is key to avoiding ganglia injury before the neck invasive procedures.


Subject(s)
Carcinoma, Papillary , Horner Syndrome , Thyroid Neoplasms , Male , Humans , Adult , Thyroid Neoplasms/complications , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/surgery , Biopsy, Fine-Needle/adverse effects , Horner Syndrome/etiology , Horner Syndrome/pathology , Iodine Radioisotopes , Carcinoma, Papillary/metabolism , Carcinoma, Papillary/pathology , Carcinoma, Papillary/surgery , Lymph Nodes/pathology , Ultrasonography, Interventional
6.
J Orthop Res ; 40(4): 891-900, 2022 04.
Article in English | MEDLINE | ID: mdl-34129247

ABSTRACT

We previously showed that femur fracture in mice caused a reduction in bone volume at distant skeletal sites within 2 weeks post-fracture. Osteocytes also have the ability to remodel their surrounding bone matrix through perilacunar/canalicular remodeling (PLR). If PLR is altered systemically following fracture, this could affect bone mechanical properties and increase fracture risk at all skeletal sites. In this study, we investigated whether lacunar-canalicular microstructure and the rate of PLR are altered in the contralateral limb following femoral fracture in mice. We hypothesized that femoral fracture would accelerate PLR by 2 weeks postfracture, followed by partial recovery by 4 weeks. We used histological evaluation and high-resolution microcomputed tomography to quantify the morphology of the lacunar-canalicular network at the contralateral tibia, and we used quantitative real-time polymerase chain reaction (RT-PCR) and RNA-seq to measure the expression of PLR-associated genes in the contralateral femur. We found that at both 2 and 4 weeks postfracture, canalicular width was significantly increased by 18.6% and 16.6%, respectively, in fractured mice relative to unfractured controls. At 3 days and 4 weeks post-fracture, we observed downregulation of PLR-associated genes; RNA-seq analysis at 3 days post-fracture showed a deceleration of bone formation and mineralization in the contralateral limb. These data demonstrate notable canalicular changes following fracture that could affect bone mechanical properties. These findings expand our understanding of systemic effects of fracture and how biological and structural changes at distant skeletal sites may contribute to increased fracture risk following an acute injury.


Subject(s)
Bone Remodeling , Femoral Fractures , Animals , Femoral Fractures/diagnostic imaging , Femoral Fractures/metabolism , Femur , Mice , Osteocytes/metabolism , X-Ray Microtomography
7.
Spine (Phila Pa 1976) ; 46(4): E243-E249, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33475276

ABSTRACT

STUDY DESIGN: An in vitro experimental study testing a Gelatin-poly (γ-glutamic acid) hydrogel for disc repair. OBJECTIVE: To evaluate the cytocompatibility and degradability of the above mentioned hydrogel for intervertebral disc annular fibrosis (AF) repair. SUMMARY OF BACKGROUND DATA: No repair strategies for correcting annular defects in lumbar discectomy have been clinically well recognized. Exogenous supplementation of regenerative materials to fill defects is a minimally invasive way to restore compromised mechanical properties. The injected materials, most commonly gelatin-based materials with cross-linking agents, serve as sealants and as a scaffold for incorporating biomaterials for augmentation. However, cytotoxicity of hydrogel crosslinking agents is of concern in developing viable materials. METHODS: This in vitro experimental study evaluated a newly developed gelatin-based hydrogel for intervertebral disc AF repair. Mechanical strength was augmented by γ-PGA, and 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC) was used for material crosslinking. Isolated bovine tail intervertebral discs (IVDs) were used to test the hydrogel, and hydrogel surface monolayer AF cell culture was used to investigate efficacy in hydrogel constructs of different EDC concentrations. Cell metabolic activity was evaluated with Alamar blue assay, cell viability assay with live/dead stain, and sulfated glycosaminoglycan (GAG) and double strain DNA were quantified to evaluate proliferation of implanted cells and synthesis of extracellular matrix (ECM) proteins. RESULTS: EDC concentrations from 10 to 40 mM resulted in significant decreases in AF cell proliferation without obvious influence on cell viability. Higher EDC concentrations resulted in decreased percentage of Alamar blue reduction and GAG and DNA concentration, but did not affect GAG/DNA and live-dead ratios. Degradation tests revealed that higher EDC concentrations decreased the hydrogel degradation rate. CONCLUSION: The developed gelatin-poly (γ-PGA) hydrogel with 20 mM EDC concentration provides an effective gap-filling biomaterial with good cytocompatibility, suggesting substantial promise for use as a sealant for small AF defects.Level of Evidence: N/A.


Subject(s)
Adhesives/therapeutic use , Gelatin/pharmacology , Glutamic Acid/pharmacology , Intervertebral Disc Degeneration/drug therapy , Intervertebral Disc/drug effects , Animals , Annulus Fibrosus/surgery , Biocompatible Materials , Cattle , Cells, Cultured , Diskectomy , Glutamic Acid/metabolism , Glycosaminoglycans , Hydrogels , Intervertebral Disc/surgery , Intervertebral Disc Degeneration/surgery , Polyglutamic Acid/analogs & derivatives
8.
Liver Cancer ; 8(3): 155-171, 2019 May.
Article in English | MEDLINE | ID: mdl-31192153

ABSTRACT

BACKGROUND: Anti-programmed cell death-1(anti-PD1) treatment has shown promising antitumor efficacy in patients with advanced hepatocellular carcinoma (HCC). This study sought to explore the functional significance of programmed death ligand-1 (PD-L1) expression in tumor cells in the tumor microenvironment. METHODS: The mouse liver cancer cell line BNL-MEA was transfected with PD-L1 plasmids and stable clones expressing PD-L1 were selected. An orthotopic HCC model was generated by implanting the cells into the subcapsular space of BALB/c mice. Cell growth features were measured by proliferation assay, colony formation, flow cytometry (in vitro), ultrasonography, and animal survival (in vivo). The changes in T-cell function were examined by cytokine assay, expression of T-cell related genes, and flow cytometry. The efficacy of anti-PD1 therapy was compared between the parental and PD-L1-expressing tumors. RESULTS: PD-L1 expression did not affect growth characteristics of BNL-MEA cells but downregulated the expression of genes related to T-cell activation in the tumor microenvironment. Co-culture of PD-L1-expressing BNL-MEA cells with CD8+ T cells reduced T-cell proliferation and expression of cytokines IFNγ and TNFα. Tumors with PD-L1 expression showed better response to anti-PD1 therapy and depletion of CD8+ T cells abolished the antitumor effect. The difference in treatment response between parental and PD-L1-expressing tumors disappeared when a combination of anti-PD1 and sorafenib was given. CONCLUSIONS: PD-L1 expression in HCC cells may inhibit T-cell function in the liver tumor microenvironment. Anti-PD1 therapy appeared more effective in PD-L1-expressing than nonexpressing tumors, but the difference was diminished by the addition of sorafenib.

9.
Semin Liver Dis ; 38(4): 379-388, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30357775

ABSTRACT

Multikinase inhibitors with antiangiogenic properties used to be standard therapy for patients with advanced hepatocellular carcinoma (HCC). Recently, several antiangiogenic agents (lenvatinib, cabozantinib, and ramucirumab) have demonstrated antitumor activity for advanced HCC in randomized controlled trials. However, the landscape of drug development for HCC may change dramatically with the advent of immune checkpoint inhibitor therapy, particularly the anti-programmed cell death-1 (anti-PD1) agents. In addition, early-phase clinical trials of combination of anti-PD-1 and antiangiogenic agents have shown very promising anti-tumor activity in patients with advanced HCC. Therefore, the critical research questions at present are whether this combination strategy will be the next generation of standard therapy and which antiangiogenic agents will be the optimal partner for the combination. All of the 4 multikinase inhibitors for HCC (sorafenib, regorafenib, lenvatinib, and cabozantinib) have been reported to have immune modulatory effects. The authors systematically reviewed the pre-clinical evidence of their immune modulatory effects to explore whether these effects were mediated by angiogenesis inhibition or by other "off-target" effects on the tumor microenvironment. Studies of sorafenib comprised the majority (58 of the 71) of the research articles reviewed. Potentially beneficial effects on anti-tumor immunity may result from increased M1 polarization of macrophages and stimulation of CD8 T cell function. On the other hand, high dosage of the kinase inhibitors in pre-clinical models and hypoxia associated with angiogenesis may contribute to immune suppression in the tumor microenvironment. Sorafenib and other multikinase inhibitors may promote anti-tumor immunity through modulation of multiple immune cell types as well as the tumor microenvironment. The optimal immune modulatory dosage should be defined to facilitate design of future combination regimens.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Carcinoma, Hepatocellular/drug therapy , Immunotherapy/methods , Liver Neoplasms/drug therapy , Molecular Targeted Therapy/methods , Protein Kinase Inhibitors/therapeutic use , Anilides/therapeutic use , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/immunology , Clinical Trials as Topic , Humans , Liver Neoplasms/immunology , Phenylurea Compounds/therapeutic use , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Pyridines/therapeutic use , Quinolines/therapeutic use , Ramucirumab
10.
J Ophthalmol ; 2018: 2159702, 2018.
Article in English | MEDLINE | ID: mdl-30275989

ABSTRACT

Entropy images, representing the complexity of original fundus photographs, may strengthen the contrast between diabetic retinopathy (DR) lesions and unaffected areas. The aim of this study is to compare the detection performance for severe DR between original fundus photographs and entropy images by deep learning. A sample of 21,123 interpretable fundus photographs obtained from a publicly available data set was expanded to 33,000 images by rotating and flipping. All photographs were transformed into entropy images using block size 9 and downsized to a standard resolution of 100 × 100 pixels. The stages of DR are classified into 5 grades based on the International Clinical Diabetic Retinopathy Disease Severity Scale: Grade 0 (no DR), Grade 1 (mild nonproliferative DR), Grade 2 (moderate nonproliferative DR), Grade 3 (severe nonproliferative DR), and Grade 4 (proliferative DR). Of these 33,000 photographs, 30,000 images were randomly selected as the training set, and the remaining 3,000 images were used as the testing set. Both the original fundus photographs and the entropy images were used as the inputs of convolutional neural network (CNN), and the results of detecting referable DR (Grades 2-4) as the outputs from the two data sets were compared. The detection accuracy, sensitivity, and specificity of using the original fundus photographs data set were 81.80%, 68.36%, 89.87%, respectively, for the entropy images data set, and the figures significantly increased to 86.10%, 73.24%, and 93.81%, respectively (all p values <0.001). The entropy image quantifies the amount of information in the fundus photograph and efficiently accelerates the generating of feature maps in the CNN. The research results draw the conclusion that transformed entropy imaging of fundus photographs can increase the machinery detection accuracy, sensitivity, and specificity of referable DR for the deep learning-based system.

11.
J Chin Med Assoc ; 81(1): 81-86, 2018 01.
Article in English | MEDLINE | ID: mdl-28974355

ABSTRACT

BACKGROUND: More and more elderly problems come to our life and the elderly health care become more important. Elderly people with lower extremities weakness usually use walkers to assist in walking. Although the commercial standard walkers (N-type) can improve elderly people's walking ability, users sometimes take risk of falling when using the standard walkers to perform sit-to-stand (STS). The purpose of this study is to design an additional armrest which can be attached to a standard walker for users performing STS more easily and evaluate it with clinical assessments and a body worn sensor. METHODS: The combination of the walker and the new armrest design are referred to as a better type (B-type). Clinical assessments and a motion analysis were performed on 34 elderly people (age, 83 ± 6 y/o) with a Five Times Sit-to-Stand Test (FTSST), a satisfaction survey and an inertial measurement unit (IMU) attached to the trunk to measure the acceleration data when using B-type and N-type during STS. RESULTS: The FTSST result shows that the B-type can reduce about 5 s spending time of elderly people during STS and 63.7% of subjects were more satisfied on the B-type than the N-type. According to the IMU, the result reveals that the B-type can provide subjects higher peak-peak anterio-posterior acceleration, peak flexion acceleration and peak extension acceleration during STS. CONCLUSION: There is a better assistance during STS when using our new armrests design combined with the commercial product which could provide larger acceleration to perform sit-to-stand.


Subject(s)
Muscle Strength/physiology , Postural Balance , Walkers , Aged , Aged, 80 and over , Female , Humans , Male
12.
PLoS One ; 9(6): e98894, 2014.
Article in English | MEDLINE | ID: mdl-24896240

ABSTRACT

Gastric cancer (GC) is one of the leading causes of cancer death in the world. The role of histone deacetylase 4 (HDAC4) in specific cell and tissue types has been identified. However, its biological roles in the development of gastric cancer remain largely unexplored. Quantitative real time PCR (qRT-PCR) and western blot were used to analyze the expression of HDAC4 in the clinical samples. siRNA and overexpression of HDAC4 and siRNA p21 were used to study functional effects in a proliferation, a colony formation, a adenosine 5'-triphosphate (ATP) assay and reactive oxygen species(ROS) generation, cell cycle, cell apoptosis rates, and autophagy assays. HDAC4 was up-regulated in gastric cancer tissues and several gastric cancer cell lines. The proliferation, colony formation ability and ATP level were enhanced in HDAC4 overexpression SGC-7901 cells, but inhibited in HDAC4 knockdown SGC-7901 cells. HDAC4 knockdown led to G0/G1 phase cell arrest and caused apoptosis and ROS increase. Moreover, HDAC4 was found to inhibit p21 expression in gastric cancer SGC-7901 cells. p21 knockdown dramatically attenuated cell proliferation inhibition, cell cycle arrest, cell apoptosis promotion and autophagy up-regulation in HDAC4-siRNA SGC-7901 cells. We demonstrated that HDAC4 promotes gastric cancer cell progression mediated through the repression of p21. Our results provide an experimental basis for understanding the pro-tumor mechanism of HDAC4 as treatment for gastric cancer.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21/genetics , Gene Expression Regulation, Neoplastic , Histone Deacetylases/metabolism , Repressor Proteins/metabolism , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Adenosine Triphosphate/metabolism , Aged , Apoptosis/genetics , Case-Control Studies , Cell Cycle Checkpoints/genetics , Cell Line, Tumor , Cell Proliferation , Histone Deacetylases/genetics , Humans , Middle Aged , Reactive Oxygen Species/metabolism , Repressor Proteins/genetics , Stomach Neoplasms/pathology , Tumor Stem Cell Assay
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