➤ Bone and muscle tissues are in close relationship, and the aging process is a factor involved in the loss of the functionality of both bones and muscles.➤ Sarcopenia and osteoporosis are linked ...from a biological and functional perspective and are related to an increased fracture risk in the elderly.➤ The increased fracture risk in sarcopenic and osteoporotic subjects is due to the decline of muscle mass and strength, the decrease in bone mineral density, and limited mobility.
Fiber‐based approaches hold great promise for tendon tissue engineering enabling the possibility of manufacturing aligned hydrogel filaments that can guide collagen fiber orientation, thereby ...providing a biomimetic micro‐environment for cell attachment, orientation, migration, and proliferation. In this study, a 3D system composed of cell‐laden, highly aligned hydrogel yarns is designed and obtained via wet spinning in order to reproduce the morphology and structure of tendon fascicles. A bioink composed of alginate and gelatin methacryloyl (GelMA) is optimized for spinning and loaded with human bone morrow mesenchymal stem cells (hBM‐MSCs). The produced scaffolds are subjected to mechanical stretching to recapitulate the strains occurring in native tendon tissue. Stem cell differentiation is promoted by addition of bone morphogenetic protein 12 (BMP‐12) in the culture medium. The aligned orientation of the fibers combined with mechanical stimulation results in highly preferential longitudinal cell orientation and demonstrates enhanced collagen type I and III expression. Additionally, the combination of biochemical and mechanical stimulations promotes the expression of specific tenogenic markers, signatures of efficient cell differentiation towards tendon. The obtained results suggest that the proposed 3D cell‐laden aligned system can be used for engineering of scaffolds for tendon regeneration.
Highly aligned hydrogel yarns are fabricated using a novel system employing a wet‐spinning technique to recapitulate the structure and morphology of tendon tissue. Scaffolds are loaded with human bone‐marrow‐derived stem cells and subjected to mechanical stretching and biochemical stimulation. The combined effect of these stimuli results in cell preferential orientation, tenogenic differentiation, and collagen expression.
Locked titanium nails are considered the reference treatment for metastatic bone lesions of the humerus in patients with aggressive histotypes, high risk of fracture or when estimated survival is ...lower than 6 months.Nevertheless, they are responsible for CT and MRI artifacts which interfere with postoperative radiotherapy and follow-up.The IlluminOss® is an intramedullary stabilization system which is introduced inside the humeral canal in a deflated state, and is then distended with a monomer which hardens after exposure to blue light,stabilizing the segment; it does not cause artifacts, allowing easier and more effective radiotherapy and follow-up. The aim of this study is to report our experience, indications, possible advantages and limitations of this stabilization system at 24 months of minimum follow-up in a series of 12 patients affected by pathological fractures or impending fractures of the humerus.
This is a retrospective case-series that included all patients who underwent surgery with the IlluminOss® Photodynamic Bone Stabilization System for pathological osteolyses and fractures of the humerus. Intraoperative and postoperative complications were valued.
12 patients and 13 procedures were included in the study. All surgeries were performed without intraoperative complications. No early postoperative complications were noted. The wounds healed in all cases and stitches were removed at two weeks from surgery, so the patients were able to perform chemotherapy after three weeks. All patients except one had a painless active range of motion which reached 90°.The VAS score was 7 preoperatively and 2.6 at one month from surgery. Pain relief was also associated to radiotherapy and chemotherapy. Unfortunately, two nail ruptures were reported at 4 and 12 months of follow-up. No artifacts were noted in the postoperative CT scans so the radiotherapy plans were easily performed without the need of dose compensation.
The IlluminOss® intramedullary stabilization system can provide primary stability in humeral fractures and impending fractures;the surgical technique is easy and minimally invasive.Moreover,it does not present artifacts at postoperative imaging,probably giving a better chance to perform prompt radiotherapy and chemotherapy.However, randomized clinical studies are necessary to verify its potential strength and if precocious adjuvant radio- and chemotherapy are associated to a reduction of the local progression rate.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Giant cell tumour of bone (GCTB) is a benign, locally aggressive primary bone neoplasm that represents 5% of all bone tumours. The principal treatment approach is surgery. Although generally GCTB is ...considered only a locally aggressive disease, it can metastasise, and lung metastases occur in 1–9% of patients. To date, only the use of denosumab has been approved as medical treatment for GCTB. Even more rarely, GCTB undergoes sarcomatous transformation into a malignant tumour (4% of all GCTB), but history of this malignant transformation is unclear and unpredictable. Considering the rarity of the event, the data in the literature are few. In this review, we summarise published data of GCTB malignant transformation and we analyse three cases of malignant transformation of GCTB, evaluating histopathology, genetics, and radiological aspects. Despite the rarity of this event, we conclude that a strict follow up is recommended to detect early malignant transformation.
The importance of skeletal muscle tissue is undoubted being the controller of several vital functions including respiration and all voluntary locomotion activities. However, its regenerative ...capability is limited and significant tissue loss often leads to a chronic pathologic condition known as volumetric muscle loss. Here, we propose a biofabrication approach to rapidly restore skeletal muscle mass, 3D histoarchitecture, and functionality. By recapitulating muscle anisotropic organization at the microscale level, we demonstrate to efficiently guide cell differentiation and myobundle formation both in vitro and in vivo. Of note, upon implantation, the biofabricated myo‐substitutes support the formation of new blood vessels and neuromuscular junctions—pivotal aspects for cell survival and muscle contractile functionalities—together with an advanced muscle mass and force recovery. Altogether, these data represent a solid base for further testing the myo‐substitutes in large animal size and a promising platform to be eventually translated into clinical scenarios.
Synopsis
The regenerative capability of skeletal muscle tissue is limited and significant tissue loss often leads to a chronic pathologic condition known as volumetric muscle loss. By exploiting the potentials of our biofabrication approach, one can manufacture advanced cell‐laden myo‐substitutes that ultimately may restore the functionalities of severely damaged skeletal muscles in vivo.
Biofabricated myo‐substitutes may represent a valid candidate for volumetric muscle loss treatment.
Upon implantation, biofabricated myo‐substitutes support the formation of new blood vessels and neuromuscular junctions together with an advanced muscle mass and force recovery.
The employed biofabrication approach is compatible with human primary stem cells ‐ namely pericytes.
The regenerative capability of skeletal muscle tissue is limited and significant tissue loss often leads to a chronic pathologic condition known as volumetric muscle loss. By exploiting the potentials of our biofabrication approach, one can manufacture advanced cell‐laden myo‐substitutes that ultimately may restore the functionalities of severely damaged skeletal muscles in vivo.
Osteoporosis and sarcopenia: the connections Tarantino, Umberto; Baldi, Jacopo; Celi, Monica ...
Aging Clinical and Experimental Research,
10/2013, Letnik:
25, Številka:
Suppl 1
Journal Article
Recenzirano
Odprti dostop
Osteoporosis and sarcopenia are the most frequent musculoskeletal disorders affecting older people. Osteoporosis is a widespread disorder affecting millions of individuals of all ethnic backgrounds ...worldwide, particularly among older women. It is characterized by reduced bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in the risk of fracture. Sarcopenia is considered to be one of the major factors responsible for functional limitations and motor dependency in elderly persons. In age-related muscle atrophy, a decrease in muscle fiber size and number, and a preferential loss of type II fibers have been reported. A decrease in the circulating levels of specific hormones (e.g., estrogen, testosterone, growth hormone, and insulin-like growth factor-1) has been shown to be associated with sarcopenia and this appears to play an important role in its pathogenesis.
Skeletal muscle tissue is characterized by restrained self-regenerative capabilities, being ineffective in relation to trauma extension both in time span (e.g., chronic diseases) and in size (e.g., ...large trauma). For these reasons, tissue engineering and/or cellular therapies represent a valuable solution in the cases where the physiological healing process failed. Satellite cells, the putative skeletal muscle stem cells, have been the first solution explored to remedy the insufficient self-regeneration capacity. Nevertheless, some limitation related to donor age, muscle condition, expansion hitch, and myogenic potentiality maintenance have limited their use as therapeutic tool. To overcome this hindrance, different stem cells population with myogenic capabilities have been investigated to evaluate their real potentiality for therapeutic approaches, but, as of today, the perfect cell candidate has not been identified yet. In this work, we analyze the characteristics of skeletal muscle-derived human Mesenchymal Stem Cells (hMSCs), showing the maintenance/increment of myogenic activity upon differential culture conditions. In particular, we investigate the influence of a commercial enriched growth medium (Cyto-Grow), and of a medium enriched with either human-derived serum (H.S.) or human Platelet-rich Plasma (PrP), in order to set up a culture protocol useful for employing this cell population in clinical therapeutic strategies. The presented results reveal that both the enriched medium (Cyto-Grow) and the human-derived supplements (H.S. and PrP) have remarkable effects on hMSCs proliferation and myogenic differentiation compared to standard condition, uncovering the real possibility to exploit these human derivatives to ameliorate stem cells yield and efficacy.
Wide resection is currently considered the mainstay treatment for primary bone tumors. When the tumor is located in anatomically complex segments, 3D-Printed Titanium Custom-Made Prostheses (3DPTCMP) ...are possible reconstructive solutions. The aim of the present paper is to analyze indications, results and complications of a series of 14 patients who underwent pelvis reconstruction with 3DPTCMP after tumor removal from January 2015 to December 2019. Chondrosarcoma was the main histology; indications were tumors located in the acetabular area without enough residual bone to support a cup with an iliac stem, and tumors located near the sacrum-iliac joint. The margins were wide in 12 cases, and marginal and intralesional in one case each. In three cases, resection also included the sacrum-iliac joint, so a spine stabilization was performed and linked to the pelvic prosthesis; The average MSTS score was 46.3%; the 5-year local recurrence-free survival was 85.7%. Wound dehiscences were the main complication, resolved with multiple debridements; nevertheless, prosthesis removal was necessary in one case. Currently, the 3DPTCMP is an effective resource for reconstruction after resection of tumors located in the pelvis. Further studies are necessary to value long-term results; more strategies are necessary to try to reduce the infection rate and improve osteointegration.
Purpose
To determine diagnostic performance of MRI radiomics-based machine learning for classification of deep-seated lipoma and atypical lipomatous tumor (ALT) of the extremities.
Material and ...methods
This retrospective study was performed at three tertiary sarcoma centers and included 150 patients with surgically treated and histology-proven lesions. The training-validation cohort consisted of 114 patients from centers 1 and 2 (n = 64 lipoma, n = 50 ALT). The external test cohort consisted of 36 patients from center 3 (n = 24 lipoma, n = 12 ALT). 3D segmentation was manually performed on T1- and T2-weighted MRI. After extraction and selection of radiomic features, three machine learning classifiers were trained and validated using nested fivefold cross-validation. The best-performing classifier according to previous analysis was evaluated and compared to an experienced musculoskeletal radiologist in the external test cohort.
Results
Eight features passed feature selection and were incorporated into the machine learning models. After training and validation (74% ROC-AUC), the best-performing classifier (Random Forest) showed 92% sensitivity and 33% specificity in the external test cohort with no statistical difference compared to the radiologist (
p
= 0.474).
Conclusion
MRI radiomics-based machine learning may classify deep-seated lipoma and ALT of the extremities with high sensitivity and negative predictive value, thus potentially serving as a non-invasive screening tool to reduce unnecessary referral to tertiary tumor centers.
Background
Sarcopenia and osteoporosis increase the risk of bone fracture in the elderly due to the loss of muscle mass and the decrease in bone mineral density. Myostatin and Bone Morphogenetic ...Proteins (BMPs) are important molecules involved in muscle mass homeostasis.
Aim
In this study, we investigated the role of BMP4 and myostatin in the pathophysiogenesis of sarcopenia related to osteoporosis and osteoarthritis.
Methods
Muscle atrophy, BMP4 and myostatin expression were evaluated in 27 biopsies of osteoarthritic (OA) women and 27 biopsies from osteoporotic (OP) group by immunohistochemical reaction. Muscle stem cell niches were investigated by transmission electron microscopy analysis.
Results
Myostatin and BMP4 expression was evaluated by counting the number of positive fibers on 25 high-power field. We found that OA muscle biopsies showed a significantly higher number of BMP4-positive fibers (37.35 ± 5.63) as compared with muscle of OP patients (9.60 ± 1.57). Unlike BMP4 expression, the number of myostatin-positive fibers in OP patients (33.95 ± 4.10) was significantly higher compared to OA group (13.86 ± 1.68). The ultrastructural analysis of BMP4-positive tissues displayed the presence of a high rate of satellite cells both single or as syncytium giving proof of muscle regeneration capability.
Discussion
Our results indicated that sarcopenia and osteoporosis shared an impairment of metabolic activity. Conversely, the molecular mechanisms of OA seem to inhibit the onset of an age-related sarcopenia.
Conclusion
The characterization of molecular mechanisms underlying the bone–muscle crosstalk could open new therapeutic perspectives in elderly diseases.
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