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1.
Article in English | MEDLINE | ID: mdl-38512739

ABSTRACT

This study proposes a charge-mode neural stimulator for electrical stimulation systems that utilizes a capacitor-reuse technique with a residual charge detector and achieves active charge balancing simultaneously. The design is mainly used for epilepsy suppression systems to achieve real-time symptom relief during seizures. A charge-mode stimulator is adopted in consideration of the complexity of circuit design, the high voltage tolerance of transistors, and system integration requirements in the future. The residual charge detector allows users to understand the current stimulus situation, enabling them to make optimal adjustments to the stimulation parameters. On the basis of the information on actual stimulation charge, active charge balancing can effectively prevent the accumulation of mismatched charges on electrode impedance. The capacitor- and phase-reuse techniques help realize high integration of the overall stimulator circuit in consideration of the commonality of the use of a capacitor and charging/discharging phase in the stimulation circuit and charge detector. The proposed charge-mode neural stimulator is implemented in a TSMC 0.18 µm 1P6M CMOS process with a core area of 0.2127 mm2. Measurement results demonstrate the accuracy of the stimulation's functionality and the programmable stimulus parameters. The effectiveness of the proposed charge-mode neural stimulator for epileptic seizure suppression is verified through animal experiments.

2.
Genes Dis ; 11(3): 101004, 2024 May.
Article in English | MEDLINE | ID: mdl-38292182

ABSTRACT

MYBL2 (MYB proto-oncogene like 2) is an emerging prognostic marker for malignant tumors, and its potential role in osteosarcoma and its relationship with immune infiltration in pan-cancer is yet to be elucidated. We constructed a transcription factor activity profile of osteosarcoma using the single-cell regulatory network inference algorithm based on single-cell RNA sequencing data obtained from the Gene Expression Omnibus. Subsequently, we calculated the extent of MYBL2 activation in malignant proliferative osteoblasts. We also explored the association between MYBL2 and chemotherapy resistance in osteosarcoma. Furthermore, we systematically correlated MYBL2 with immunological signatures in the tumor microenvironment in pan-cancer, including immune cell infiltration, immune checkpoints, and tumor immunotherapy prognosis. Finally, we developed and validated a risk score (MRGS), derived an osteosarcoma risk score nomogram based on MRGS, and tested its ability to predict prognosis. MYBL2 and gene enrichment analyses in osteosarcoma and pan-cancer revealed that MYBL2 was positively correlated with cell proliferation and tumor immune pathways. MYBL2 expression positively correlated with SLC19A1 in pan-cancer and osteosarcoma cell lines. Pan-cancer immune infiltration analysis revealed that MYBL2 was correlated with myeloid-derived suppressor cells, Th2 cell infiltration, CD276, RELT gene expression, and tumor mutation burden. In summary, MYBL2 regulates proliferation, progression, and immune infiltration in osteosarcoma and pan-cancer. Therefore, we found that MYBL2 could be used as a potential marker for predicting the osteosarcoma prognosis. Patients with osteosarcoma and high MYBL2 expression are theoretically more sensitive to methotrexate. An osteosarcoma prognostic nomogram can provide new ideas in the search for osteosarcoma prognostic markers.

3.
Micron ; 175: 103536, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37703802

ABSTRACT

Automated microscope systems have played an important role in the screening of numerous diseases. However, it is a very time-consuming process to continuously acquire images under the high magnification objective lens. This paper proposes a dynamic parallel image acquisition method, which can greatly improve image acquisition speed. Due to the relative motion between the x-y stage and the camera, some of the captured images have motion blur To this end, we also designed a motor variable speed motion curve to ensure the quality of the collected images. The experimental results show that the traditional image scanning mode needs 47.3 ms to obtain continuous microscopic images, while the dynamic parallel image acquisition method only needs 25.4 ms, which improves the acquisition speed without affecting the clarity of the acquired images.

4.
Comput Biol Chem ; 106: 107929, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37517206

ABSTRACT

Identifying lowly prevalent diseases, or rare diseases, in their early stages is key to disease treatment in the medical field. Deep learning techniques now provide promising tools for this purpose. Nevertheless, the low prevalence of rare diseases entangles the proper application of deep networks for disease identification due to the severe class-imbalance issue. In the past decades, some balancing methods have been studied to handle the data-imbalance issue. The bad news is that it is verified that none of these methods guarantees superior performance to others. This performance variation causes the need to formulate a systematic pipeline with a comprehensive software tool for enhancing deep-learning applications in rare disease identification. We reviewed the existing balancing schemes and summarized a systematic deep ensemble pipeline with a constructed tool called RDDL for handling the data imbalance issue. Through two real case studies, we showed that rare disease identification could be boosted with this systematic RDDL pipeline tool by lessening the data imbalance problem during model training. The RDDL pipeline tool is available at https://github.com/cobisLab/RDDL/.


Subject(s)
Deep Learning , Humans , Rare Diseases , Software
5.
Microsc Res Tech ; 86(7): 773-780, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37154261

ABSTRACT

Piezoelectric objective driver positioners are increasingly used in the field of microscopy. They have the advantages of high dynamic and fast response. This paper presents a fast autofocus algorithm for highly interactive microscope system. First, the Tenengrad gradient of the down-sampled image is used to calculate the image sharpness, and Brent search method is adopted to quickly converge to the correct focal length. At the same time, the input shaping method is used to eliminate the displacement vibration of the piezoelectric objective lens driver and further accelerate the image acquisition speed. Experimental results show that the proposed scheme can improve the speed of the automatic focusing task of the piezoelectric objective driver and improve the real-time focus of the automatic microscopic system. HIGHLIGHTS: A high real-time autofocus strategy. A vibration control method suitable for a piezoelectric objective driver.

6.
Materials (Basel) ; 16(6)2023 Mar 11.
Article in English | MEDLINE | ID: mdl-36984152

ABSTRACT

Piezoelectric actuators are characterized by high positioning accuracy, high stiffness and a fast response and are widely used in ultra-precision machining technologies such as fast tool servo technology and ultrasonic machining. The rapid response characteristics of piezoelectric actuators often determine the overall quality of machining. However, there has been little research on the fast response characteristics of piezoelectric actuators, and this knowledge gap will lead to low precision and poor quality of the final machining. The fast response characteristics of a piezoelectric actuator were studied in this work. Firstly, the piezoelectric actuator was divided into a no-load state and a load state according to the working state. A fast response analysis and output characteristic analysis were carried out, the corresponding dynamic model was established, and then the model was simulated. Finally, an experimental system was established to verify the dynamic model of the piezoelectric actuator's fast response by conducting an experiment in which the piezoelectric actuator bounces a steel ball. The experimental results verify the correctness of the model and show that the greater the cross-sectional area and height of the piezoelectric actuator, the higher the bouncing height of the ball, and the better the dynamic performance of the piezoelectric actuator. It is believed that this study has guiding significance for the application of the dynamic characteristics of piezoelectric actuators in the machining field.

7.
ACS Appl Mater Interfaces ; 14(37): 41764-41778, 2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36087275

ABSTRACT

3D-printed porous tantalum scaffold has been increasingly used in arthroplasty due to its bone-matching elastic modulus and good osteoinductive ability. However, the lack of antibacterial ability makes it difficult for tantalum to prevent the occurrence and development of periprosthetic joint infection. The difficulty and high cost of curing periprosthetic joint infection (PJI) and revision surgery limit the further clinical application of tantalum. Therefore, we fabricated vancomycin-loaded porous tantalum scaffolds by combining the chemical grafting of (3-aminopropyl)triethoxysilane (APTES) and the electrostatic assembly of carboxymethyl chitosan and vancomycin for the first time. Our in vitro experiments show that the scaffold achieves rapid killing of initially adherent bacteria and effectively prevents biofilm formation. In addition, our modification preserves the original excellent structure and biocompatibility of porous tantalum and promotes the generation of mineralized matrix and osteogenesis-related gene expression by mesenchymal stem cells on the surface of scaffolds. Through a rat subcutaneous infection model, the composite bioscaffold shows efficient bacterial clearance and inflammation control in soft tissue and creates an immune microenvironment suitable for tissue repair at an early stage. Combined with the economic friendliness and practicality of its preparation, this scaffold has great clinical application potential in the treatment of periprosthetic joint infection.


Subject(s)
Chitosan , Prosthesis-Related Infections , Animals , Anti-Bacterial Agents/pharmacology , Biofilms , Chitosan/pharmacology , Osteogenesis , Porosity , Printing, Three-Dimensional , Rats , Tantalum/pharmacology , Tissue Scaffolds/chemistry , Vancomycin/pharmacology
8.
Comput Struct Biotechnol J ; 20: 2473-2483, 2022.
Article in English | MEDLINE | ID: mdl-35664227

ABSTRACT

RNA secondary structures can carry out essential cellular functions alone or interact with one another to form the hierarchical tertiary structures. Experimental structure identification approa ches can show the in vitro structures of RNA molecules. However, they usually have limits in the resolution and are costly. In silico structure prediction tools are thus primarily relied on for pre-experiment analysis. Various structure prediction models have been developed over the decades. Since these tools are usually used before knowing the actual RNA structures, evaluating and ranking the pile of secondary structure predictions of a given sequence is essential in computational analysis. In this research, we implemented a web service called SSRTool (RNA Secondary Structure prediction Ranking Tool) to assist in the ranking and evaluation of the generated predicted structures of a given sequence. Based on the computed species-specific interpretability significance in four common RNA structure-function aspects, SSRTool provides three functions along with visualization interfaces: (1) Rank user-generated predictions. (2) Provide an automated streamline of structure prediction and ranking for a given sequence. (3) Infer the functional aspects of a given structure. We demonstrated the applicability of SSRTool via real case studies and reported the similar trends between computed species-specific rankings and the corresponding prediction F1 values. The SSRTool web service is available online at https://cobisHSS0.im.nuk.edu.tw/SSRTool/, http://cosbi3.ee.ncku.edu.tw/SSRTool/, or the redirecting site https://github.com/cobisLab/SSRTool/.

10.
Mol Med Rep ; 24(3)2021 Sep.
Article in English | MEDLINE | ID: mdl-34296294

ABSTRACT

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the Transwell cell migration assay data shown in Figs. 4B and 5B were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 12: 6316­6322, 2015; DOI: 10.3892/mmr.2015.4165].

11.
IEEE Trans Biomed Circuits Syst ; 15(3): 537-548, 2021 06.
Article in English | MEDLINE | ID: mdl-34101596

ABSTRACT

This work presents a portable wireless urine detection system which consists of an electrochemical readout application specific integrated circuit (ASIC) and a biosensor composed of 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and carbon nanotube (ABTS-CNT) for the detection of urine albumin-to-creatinine ratio (UACR). The ASIC includes a potentiostat, a digital circuitry and a power management circuit which can perform electrochemistry techniques with a dual-channel screen-printing carbon electrode (SPCE). Electrochemical experiments on the proposed biosensor (SPCE|ABTS-CNT|Nafion) have revealed promising sensing characteristics for creatinine and human serum albumin detection. Practical urine tests has demonstrated the capability of the proposed urine detection system for UACR detection with both the power-efficient readout ASIC and the ABTS-CNT biosensor. A user-friendly prototype has also been designed which can be useful for either personal health administrationor homecare.


Subject(s)
Biosensing Techniques , Nanotubes, Carbon , Benzothiazoles , Electrochemical Techniques , Electrochemistry , Humans , Sulfonic Acids
12.
Am J Cancer Res ; 10(10): 3248-3266, 2020.
Article in English | MEDLINE | ID: mdl-33163268

ABSTRACT

Primary bone tumor, also known as osteosarcoma (OS), is the most common primary malignancy of bone in children and young adults. Current treatment protocols yield a 5-year survival rate of near 70% although approximately 80% of patients have metastatic disease at the time of diagnosis. However, long-term survival rates have remained virtually unchanged for nearly four decades, largely due to our limited understanding of the disease process. One major signaling pathway that has been implicated in human OS tumorigenesis is the insulin-like growth factor (IGF)/insulin-like growth factor-1 receptor (IGF1R) signaling axis. IGF1R is a heterotetrameric α2ß2 receptor, in which the α subunits comprise the ligand binding site, whereas the ß subunits are transmembrane proteins containing intracellular tyrosine kinase domains. Although numerous strategies have been devised to target IGF/IGF1R axis, most of them have failed in clinical trials due to the lack of specificity and/or limited efficacy. Here, we investigated whether a more effective and specific blockade of IGF1R activity in human OS cells can be accomplished by employing dominant-negative IGF1R (dnIGF1R) mutants. We engineered the recombinant adenoviruses expressing two IGF1R mutants derived from the α (aa 1-524) and ß (aa 741-936) subunits, and found that either dnIGF1Rα and/or dnIGF1Rß effectively inhibited cell migration, colony formation, and cell cycle progression of human OS cells, which could be reversed by exogenous IGF1. Furthermore, dnIGF1Rα and/or dnIGF1Rß inhibited OS xenograft tumor growth in vivo, with the greatest inhibition of tumor growth shown by dnIGF1Rα. Mechanistically, the dnIGF1R mutants down-regulated the expression of PI3K/AKT and RAS/RAF/MAPK, BCL2, Cyclin D1 and most EMT regulators, while up-regulating pro-apoptotic genes in human OS cells. Collectively, these findings strongly suggest that the dnIGF1R mutants, especially dnIGF1Rα, may be further developed as novel anticancer agents that target IGF signaling axis with high specificity and efficacy.

13.
Biomed Res Int ; 2020: 5180458, 2020.
Article in English | MEDLINE | ID: mdl-32964033

ABSTRACT

The supercapsular percutaneously assisted total hip (SuperPATH) approach is a microinvasive approach that was developed to minimize surgical disruption of soft tissue during routine total hip arthroplasty (THA). This study was aimed at assessing early outcomes and learning curves of the SuperPATH approach in one Chinese hospital's experience. Early outcomes of the first consecutive 78 SuperPATH cases (80 hips) performed by the same surgeon were evaluated. The patients were divided into 4 groups according to the surgical order. The incision, intraoperative blood loss, hospital stay, Harris hip score, and complication occurrence in each group were evaluated. Learning curves were assessed using operative time and intraoperative blood loss as surrogates. The operation time and intraoperative blood loss of groups A and B were more than those of groups C and D, and the difference was statistically significant (P < 0.05); however, there was no statistically significant difference between the two groups (group A vs. group B, P = 0.426; group A vs. group B, P = 0.426). There was no statistically significant difference in terms of incision length and hospital stay, and Harris hip score at the last follow-up was increased with statistically significant difference when compared with that preoperatively among the 4 groups. One case of periprosthetic fracture occurred in group A. No other complication, such as joint dislocation, sciatic nerve injury, prosthesis loosening, periprosthetic infection, and deep vein thromboembolism, occurred in the 4 groups. In summary, for surgeons who are familiar with the standard posterolateral approach, they could achieve more familiarity with SuperPATH after 40 cases of surgery.


Subject(s)
Arthroplasty, Replacement, Hip/methods , Hip/surgery , Aged , Asian People , Blood Loss, Surgical/physiopathology , Female , Hip Prosthesis , Humans , Learning Curve , Length of Stay , Male , Middle Aged , Operative Time , Range of Motion, Articular/physiology , Retrospective Studies
14.
Jpn J Clin Oncol ; 49(7): 656-663, 2019 Jul 01.
Article in English | MEDLINE | ID: mdl-30941404

ABSTRACT

OBJECTIVE: The purpose of this study is to retrospectively analyze the clinical efficacy of free fibula autograft and wrist arthroplasty in the treatment of giant cell tumors (GCT) of distal radius. METHODS: We retrospectively reviewed 26 patients with GCT of distal radius who underwent free autogenous fibula graft and wrist arthroplasty for repairing residual defect after en-block resection. The length of the fibula graft was 8.2 cm (6-10 cm). Postoperative follow-up regularly for an mean of 66.9 months. Bone healing was assessed by radiographs, pain was assessed by Visual Analog Scale (VAS) score and limb function was evaluated by Musculoskeletal Tumor Society (MSTS) score and disabilites of the arm, shoulder and hand (DASH) score. The range of motion (ROM) of wrist and grip strength were also evaluated. RESULT: There were four males and 22 females with an mean age of 36.7 years (19-60 years); the mean length of lesions was 4.8 cm (2.3-6.6 cm); 21 primary cases and five recurrent cases; eight cases of Campanacci Grade II, 18 cases of Grade III. We had no postoperative lung metastasis and only one case had a local recurrence, three cases (11%) with subluxation of lower ulnoradial joints and five cases (19%) showed narrowing of wrist joint space. The mean postoperative VAS pain score was 0.7 ± 0.7 and grip strength retained 71% of the normal hand, MSTS score was 27.7 ± 1.1 and DASH score was 9.0 ± 3.7. The ROM of the involved wrist only slightly restricted and no donor complications. Postoperative wrist joint function was significantly improved. CONCLUSION: Strict surgical resection boundary and solid reconstruction of wrist joint capsule are the key to achieving excellent oncological prognosis and function of distal radius GCT.


Subject(s)
Arthroplasty , Autografts/surgery , Bone Neoplasms/surgery , Bone Transplantation , Fibula/transplantation , Giant Cell Tumor of Bone/surgery , Radius/pathology , Wrist Joint/surgery , Adult , Bone Neoplasms/pathology , Female , Giant Cell Tumor of Bone/diagnostic imaging , Giant Cell Tumor of Bone/pathology , Humans , Male , Middle Aged , Radius/diagnostic imaging , Retrospective Studies , Transplantation, Autologous , Treatment Outcome , Wrist Joint/diagnostic imaging , Young Adult
15.
Exp Mol Pathol ; 107: 77-84, 2019 04.
Article in English | MEDLINE | ID: mdl-30703347

ABSTRACT

BACKGROUND: Osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is of much significance for bone formation, the imbalance of it would result in osteoporosis and other pathological bone defects. Increasing evidences showed that long non-coding RNAs (lncRNAs) and miRNAs played vital roles in the regulation of osteogenic differentiation. LncRNA KCNQ1OT1 was often regarded as an imprinted lncRNA and was related to tumor progression, while its function in osteogenic differentiation remained unclear. METHOD: qRT-PCR was performed to detect the expression of KCNQ1OT1, miR-214 and osteogenesis-related genes BMP2, Runx2, OPN, and OCN. Western blotting was carried out to detect osteogenesis-related markers. The osteoblastic phenotype was evidenced by alkaline phosphatase (ALP) activity and Alizarin Red S accumulation detection. Bioinformatics and luciferase assays were used to predict and validate the interaction between KCNQ1OT1 and miR-214 as well as BMP2 and miR-214. RESULTS: KCNQ1OT1 was significantly up-regulated during the process of osteogenic induction while miR-214 was contrarily down-regulated. Knockdown of KCNQ1OT1 inhibited osteogenic differentiation and down-regulated BMP2 and osteogenesis-related genes. It was also confirmed that KCNQ1OT1 directly interacted with miR-214. Meanwhile, miR-214 could bind to 3'UTR of BMP2 and therefore inhibited its expression. Furthermore, co-transfection of miR-214 inhibitor could rescue the down-regulation of BMP2 and osteogenesis-related genes and osteogenic differentiation suppression induced by KCNQ1OT1 knockdown. Moreover, miR-214 inhibitor significantly reversed the decreased protein levels of p-Smad1/5/8, Runx2 and Osterix induced by shKCNQ1OT1. CONCLUSIONS: KCNQ1OT1 positively regulated osteogenic differentiation of BMSCs by acting as a ceRNA to regulate BMP2 expression through sponging miR-214.


Subject(s)
Bone Morphogenetic Protein 2/biosynthesis , Cell Differentiation/physiology , Mesenchymal Stem Cells/cytology , MicroRNAs/metabolism , Osteogenesis/physiology , Cells, Cultured , Gene Expression Regulation/physiology , Humans , Potassium Channels, Voltage-Gated/physiology
16.
Int Immunopharmacol ; 68: 218-225, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30658315

ABSTRACT

Inducible nitric oxide synthase (iNOS) is a molecule critical for the development of inflammation-associated disorders. Its induction should be tightly controlled in order to maintain cellular homeostasis. Upon lipopolysaccharide (LPS) stimulation, iNOS, in most settings, is induced by the activation of inhibitor of κB-α (IκB-α)-nuclear factor κB (NF-κB) signaling. Farnesyl thiosalicylic acid (FTS), a synthetic small molecule that is considered to detach Ras from the inner cell membrane, has been shown to exhibit numerous anti-inflammatory functions. However, it remains unclear whether and how it affects iNOS induction in macrophages. The present study addressed this issue in cultured macrophages and endotoxemic mice. Results showed that FTS pretreatment significantly prevented LPS-induced increases in iNOS protein and mRNA expression levels in murine cultured macrophages, which were confirmed in organs in vivo from endotoxemic mice, such as the liver and lung. Mechanistic studies revealed that FTS pretreatment did not affect IκB-α degradation and NF-κB activation in LPS-treated macrophages. The nuclear transport of the active NF-κB was also not affected by FTS. But FTS pretreatment reduced the binding of NF-κB to its DNA elements, and reduced NF-κB bindings to iNOS promoter inside LPS-treated macrophages. Finally, our results showed that FST pretreatment increased mouse survival rate compared to LPS alone treatment. Taken together, these results indicate that FTS attenuates iNOS induction in macrophages likely through inhibition of iNOS mRNA transcription, providing further insight into the molecular mechanism of action of FTS in inflammatory disorder therapy.


Subject(s)
Farnesol/analogs & derivatives , Macrophages/drug effects , Nitric Oxide Synthase Type II/genetics , Salicylates/pharmacology , Animals , Cells, Cultured , Farnesol/pharmacology , Lipopolysaccharides , Liver/drug effects , Liver/metabolism , Lung/drug effects , Lung/metabolism , Macrophages/metabolism , Male , Mice, Inbred C57BL , NF-kappa B/metabolism , Nitric Oxide/metabolism , RNA, Messenger/metabolism
17.
Biosci Rep ; 39(1)2019 01 31.
Article in English | MEDLINE | ID: mdl-30626725

ABSTRACT

The morphology and histology changes in the medial meniscus after posterior cruciate ligament (PCL) rupture are poorly understood. Forty-eight rabbits were divided into matched mode pairs; each rabbit had an experimental side, in which the PCL was transacted, and a control side. At the 4, 8, 16 and 24 weeks after the PCL transection, each of the 12 rabbits was killed. Histology was performed to detect the expression of the tissue inhibitors of metalloproteinases-1 (TIMP-1), matrix metalloproteinase (MMP)-1 and MMP-13 in the medial meniscus. We found that medial meniscus displayed significant degenerative characteristics in morphology. The histological evaluation of the degeneration found that the expression levels of TIMP-1, MMP-1 and MMP-13 in the medial meniscus were higher in the experiment side than those in the control side (P<0.05). The expression of both TIMP-1 and MMP-13 was initially elevated and then decreased. The MMP-1 expression reached its peak swiftly and then maintained a relatively high level. There were clear time-dependent degenerative changes in the histology of the medial meniscus after PCL rupture. The high expression of TIMP-1, MMP-1 and MMP-13 in the cartilage may be responsible for the degeneration, and PCL rupture may trigger meniscus degradation and ultimately osteoarthritis.


Subject(s)
Matrix Metalloproteinase 13/genetics , Matrix Metalloproteinase 1/genetics , Osteoarthritis/genetics , Posterior Cruciate Ligament/metabolism , Tissue Inhibitor of Metalloproteinase-1/genetics , Animals , Disease Models, Animal , Gene Expression Regulation/genetics , Humans , Knee Injuries/genetics , Knee Injuries/physiopathology , Menisci, Tibial/metabolism , Menisci, Tibial/physiopathology , Osteoarthritis/physiopathology , Posterior Cruciate Ligament/physiopathology , Rabbits
18.
BMC Musculoskelet Disord ; 18(1): 297, 2017 Jul 11.
Article in English | MEDLINE | ID: mdl-28697792

ABSTRACT

BACKGROUND: To explore the association between the rupture of posterior cruciate ligament (PCL) and the radial displacement of medial meniscus under the conditions of different flexion and various axial loads. METHODS: The radial displacement value of medial meniscus was measured for the specimens of normal adult knee joints, including 12 intact PCLs, 6 ruptures of the anterolateral bundle (ALB), 6 ruptures of the postmedial bundle (PMB), and 12 complete ruptures. The measurement was conducted at 0°, 30°, 60°, and 90° of knee flexion angles under 200 N, 400 N, 600 N, 800 N and 1000 N of axial loads respectively. RESULTS: The displacement values of medial meniscus of the ALB rupture group increased at 0° flexion under 800 N and 1000 N, and at 30°, 60° and 90° flexion under all loads in comparison with the PCL intact group. The displacement values of the PMB rupture group was higher at 0° and 90° flexion under all loads, and at 30° and 60° flexion under 800 N and 1000 N loads. The displacement of the PCL complete rupture group increased at all flexion angles under all loads. CONCLUSIONS: Either partial or complete rupture of the PCL can increase in the radial displacement of the medial meniscus, which may explain the degenerative changes that occuring in the medial meniscus due to PCL injury. Therefore, early reestablishment of the PCL is necessarily required in order to maintain stability of the knee joint after PCL injury.


Subject(s)
Posterior Cruciate Ligament/injuries , Posterior Cruciate Ligament/pathology , Tibial Meniscus Injuries/pathology , Adult , Biomechanical Phenomena/physiology , Female , Humans , Male , Menisci, Tibial/pathology , Menisci, Tibial/physiology , Posterior Cruciate Ligament/physiology , Rupture/pathology , Tibial Meniscus Injuries/physiopathology
19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(12): 1438-1441, 2017 12 15.
Article in Chinese | MEDLINE | ID: mdl-29806383

ABSTRACT

Objective: To explore the effectiveness of expanded curettage in the treatment of chondroblastoma. Methods: The clinical data of 37 patients with chondroblastoma who were treated with expanded curettage between January 2011 and May 2016 were retrospectively analyzed. There were 24 males and 13 females, with a median age of 17 years (range, 12-30 years). There were 32 primary patients and 5 recurrent patients. Local pain was the first symptom in all patients. The average disease duration was 4.9 months (range, 2-8 months). The lesions were located in the distal femur in 10 cases, the proximal femur in 7 cases, the proximal tibia in 9 cases, the proximal humerus in 5 cases, the patella in 2 cases, the talus in 1 case, the calcaneus in 1 case, and pelvis in 2 cases. According to the Enneking staging of benign bone tumors, all tumors were rated as the 3rd stage. The length of the lesion ranged from 1.2 to 6.9 cm (mean, 3.2 cm). The lesions involved the epiphyseal plate in 19 cases. Results: All incisions healed by first intention, and no complications occurred. All patients were followed up 12-76 months, with an average of 40.5 months. At last follow-up, the Musculoskeletal Tumor Society (MSTS) score was 27.5±1.4, and the difference was significant when compared with pre-operative value (18.5±1.9) ( t=23.462, P=0.000). The chondroblastoma recurred in 1 case (2.7%) after 5 months. X-ray film showed that bone resorption was found in 6 cases, but there was no obvious collapse in the articular surface of bone graft. The limb shortening deformity occurred in 3 cases who were epiphyseal plate involvement patients and lesions located around the knee joint. But there was no varus deformity, and knee joint activity was not affected. Conclusion: Expanded curettage has advantages of low incidence of recurrence and skeletal deformity, good limb function, and it is one of the ideal options for chondroblastoma.


Subject(s)
Bone Neoplasms/surgery , Chondroblastoma/surgery , Curettage , Adolescent , Child , Female , Follow-Up Studies , Humans , Male , Neoplasm Recurrence, Local , Retrospective Studies , Tibia , Treatment Outcome , Young Adult
20.
Int J Clin Exp Med ; 8(6): 9620-9, 2015.
Article in English | MEDLINE | ID: mdl-26309636

ABSTRACT

OBJECTIVE: This study aims to investigate the biomechanical effect of posterior cruciate ligament (PCL) rupture on lateral meniscus. METHOD: The stresses of anterior horn, caudomedial part and posterior horn of lateral meniscus in cadaveric knees were recorded when the knee joints were loaded 200 to 1000 N at 0, 30, 60 and 90° of flexion. Twelve knees were tested before PCL transection (intact group), and 6 each were then tested after anterolateral bundle (ALB group) and postmedial bundle (PMB group) transection. The same knees were finally tested after complete PCL transection. RESULT: At 0°of knee flexion, the stresses of the anterior horn, caudomedial part and posterior horn were negative and compressive, and were not significantly different between intact and ALB groups, and between completely transected and PMB groups at 200 and 400 N. The stresses of the anterior horn and caudomedial part were greater in completely transected and PMB groups than in intact and ALB groups. The stresses of the posterior horn were smaller in PMB and completely transected groups than in intact and ALB groups. At 600-1000 N, the stresses were significantly different between the groups. The absolute stresses of the anterior horn and caudomedial part were in order of completely transected > PMB > ALB > intact group, while these of the posterior horn were reversed. At 30° of knee flexion, the stresses of the three parts were not significantly different between intact and PMB groups nor between completely transected and ALB groups at 200 and 400 N. The stresses in the anterior horn and caudomedial part were negative and different between completely transected and ALB groups, and positive and different between intact and PMB groups. The stresses in the posterior horn were positive and different between completely transected and ALB groups, and negative and different between intact and PMB groups. At loads of > 600 N, the stresses in the anterior horn and caudomedial part were negative in completely transected and ALB groups, and positive in intact and PMB groups. The stresses of the posterior horn were positive in completely transected and ALB groups and negative in intact and PMB groups, with significant difference between the groups. At 60° and 90° of flexion, the stresses of the anterior horn and caudomedial part were positive in completely transected and ALB groups and positive in intact and PMB groups, while the stresses of posterior horn were in the opposite directions and were significantly different between the groups at the same loads. CONCLUSION: Complete transection of PCL will result in stress changes in various parts of lateral meniscus. At 200 and 400 N, transection of ALB and PMB do not change the stress at 0° and 30° of flexion, respectively. At heavier loads (600-1000 N), the stresses at these angels are affected in ALB and PMB groups. At all loaded tested, transection of ALB and PMB results in changed stresses in all regions of lateral meniscus at 30-90° and 0-90° of flexion, respectively.

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