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Aims

In this investigation, we administered oxidative stress to nucleus pulposus cells (NPCs), recognized DNA-damage-inducible transcript 4 (DDIT4) as a component in intervertebral disc degeneration (IVDD), and devised a hydrogel capable of conveying small interfering RNA (siRNA) to IVDD.

Methods

An in vitro model for oxidative stress-induced injury in NPCs was developed to elucidate the mechanisms underlying the upregulation of DDIT4 expression, activation of the reactive oxygen species (ROS)-thioredoxin-interacting protein (TXNIP)-NLRP3 signalling pathway, and nucleus pulposus pyroptosis. Furthermore, the mechanism of action of small interfering DDIT4 (siDDIT4) on NPCs in vitro was validated. A triplex hydrogel named siDDIT4@G5-P-HA was created by adsorbing siDDIT4 onto fifth-generation polyamidoamine (PAMAM) dendrimer using van der Waals interactions, and then coating it with hyaluronic acid (HA). In addition, we established a rat puncture IVDD model to decipher the hydrogel’s mechanism in IVDD.


Bone & Joint Research
Vol. 12, Issue 2 | Pages 147 - 154
20 Feb 2023
Jia Y Qi X Ma M Cheng S Cheng B Liang C Guo X Zhang F

Aims

Osteoporosis (OP) is a metabolic bone disease, characterized by a decrease in bone mineral density (BMD). However, the research of regulatory variants has been limited for BMD. In this study, we aimed to explore novel regulatory genetic variants associated with BMD.

Methods

We conducted an integrative analysis of BMD genome-wide association study (GWAS) and regulatory single nucleotide polymorphism (rSNP) annotation information. Firstly, the discovery GWAS dataset and replication GWAS dataset were integrated with rSNP annotation database to obtain BMD associated SNP regulatory elements and SNP regulatory element-target gene (E-G) pairs, respectively. Then, the common genes were further subjected to HumanNet v2 to explore the biological effects.


Bone & Joint Research
Vol. 11, Issue 1 | Pages 26 - 28
20 Jan 2022
Ma M Tan Z Li W Zhang H Liu Y Yue C


Bone & Joint Research
Vol. 11, Issue 1 | Pages 29 - 31
20 Jan 2022
Ma M Tan Z Li W Zhang H Liu Y Yue C


Bone & Joint Research
Vol. 9, Issue 9 | Pages 578 - 586
1 Sep 2020
Ma M Liang X Wang X Zhang L Cheng S Guo X Zhang F Wen Y

Aims

Kashin-Beck disease (KBD) is a kind of chronic osteochondropathy, thought to be caused by environmental risk factors such as T-2 toxin. However, the exact aetiology of KBD remains unclear. In this study, we explored the functional relevance and biological mechanism of cartilage oligosaccharide matrix protein (COMP) in the articular cartilage damage of KBD.

Methods

The articular cartilage specimens were collected from five KBD patients and five control subjects for cell culture. The messenger RNA (mRNA) and protein expression levels were detected by quantitative reverse transcription PCR (qRT-PCR) and western blot. The survival rate of C28/I2 chondrocyte cell line was detected by MTT assay after T-2 toxin intervention. The cell viability and mRNA expression levels of apoptosis related genes between COMP-overexpression groups and control groups were examined after cell transfection.


Bone & Joint Research
Vol. 9, Issue 3 | Pages 130 - 138
1 Mar 2020
Qi X Yu F Wen Y Li P Cheng B Ma M Cheng S Zhang L Liang C Liu L Zhang F

Aims

Osteoarthritis (OA) is the most prevalent joint disease. However, the specific and definitive genetic mechanisms of OA are still unclear.

Methods

Tissue-related transcriptome-wide association studies (TWAS) of hip OA and knee OA were performed utilizing the genome-wide association study (GWAS) data of hip OA and knee OA (including 2,396 hospital-diagnosed hip OA patients versus 9,593 controls, and 4,462 hospital-diagnosed knee OA patients versus 17,885 controls) and gene expression reference to skeletal muscle and blood. The OA-associated genes identified by TWAS were further compared with the differentially expressed genes detected by the messenger RNA (mRNA) expression profiles of hip OA and knee OA. Functional enrichment and annotation analysis of identified genes was performed by the DAVID and FUMAGWAS tools.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 37
1 Mar 2002
Hernigou P Tararis G Ma M
Full Access

Purpose: The position of the patella after implantation of a total knee arthroplasty is generally determined by static measurements on the femoropatellar 30° flexion view or on a computed tomography (CT) scan in full extension. We studied the kinetics of the patellar implant between 0° and 90° on dynamic CT scans to determine the influence of torsion of the femoral and tibial components on the patellar course.

Material and methods: Twenty patients with titanium total knee arthroplasties implanted in 1991 and 1992 underwent a dynamic CT study preoperatively and during the year following prosthesis implantation. An Imatron machine was used to obtain dynamic slices during knee flexion from 0° to 90°. The patient was installed in the prone position. Slice thickness was 8 mm for images centred on the lower end of the femur. Ten 50 ms images were obtained during flexion from 0° to 90°. The technique used preoperatively and postoperatively enabled study of transversal translation and tilt of the patella.

Results: The orientation of the patellar transversal bony axis remained closely parallel to the flexion axis of the knee (i.e. the epicondylar axis) both preoperatively and postoperatively, irrespective of the orientation of the femoral and tibial components. Between 0° and 90° flexion, the prosthetic patella exhibited a translation movement laterally to medially during the first degrees of flexion then medially to laterally during the last degrees of flexion. The transversal displacement of the patellar insert was less pronounced when the femoral component was placed in external rotation from the epicondylar axis. For femoral implants in internal rotation (mean 5°), the translation of the patellar insert was a mean 1.5 mm between extension and flexion. This translation was only a mean 1 cm for implants in external rotation (mean 5°). Contact between the patellar prosthetic component and the femoral prosthetic component were more harmonious when the femoral implant was placed in external rotation. Torsion of the tibial implant did not appear to have an impact on the transversal course of the patella in this series.

Discussion, conclusion: Rotation of the femoral component influenced the relationship between the patella and the femoral component in flexion-extension movements. However, torsion of the femoral component had little effect on the position of the patella itself. The patellar remained schematically parallel to the epicondylar axis, maintaining an orientation close to that observed preoperatively. The torsion of the femoral implant is the element that modifies its position under the patella and by consequence the relations between the patella and the femoral trochleae. These modifications are more pronounced when the knee is in extension than when the knee is in 90° flexion, excepting for the lift-off phenomenon observed at 90° flexion which is related to the trapezoidal femorotibial resection spaces.