Ligament Tissue Research Articles

Biomechanical effects of Evans versus Hintermann osteotomy for treating adult acquired flatfoot deformity: a patient-specific finite element investigation.

Evans and Hintermann lateral column lengthening (LCL) procedures are both widely used to correct adult acquired flatfoot deformity (AAFD), and have both shown good clinical results. The aim of this study was to compare these two procedures in terms of corrective ability and biomechanics influence on the Chopart and subtalar joints through finite element (FE) analysis. Twelve patient-specific FE models were established and validated. The Hintermann osteotomy was performed between the medial and posterior facets of the subtalar joint; while, the Evans osteotomy was performed on the anterior neck of the calcaneus around 10mm from the calcaneocuboid joint surface. In each procedure, a triangular wedge of varying size was inserted at the lateral edge. The two procedures were then compared based on the measured strains of superomedial calcaneonavicular ligaments and planter facia, the talus-first metatarsal angle, and the contact characteristics of talonavicular, calcaneocuboid and subtalar joints. The Hintermann procedure achieved a greater correction of the talus-first metatarsal angle than Evans when using grafts of the same size, indicating that Hintermann had stronger corrective ability. However, its distributions of von-Mises stress in the subtalar, talonavicular and calcaneocuboid joints were lesshomogeneous than those of Evans. In addition, the strains of superomedial calcaneonavicular ligaments and planter facia of Hintermann were also greater than those of Evans, but both generally within the safe range (less than 6%). This FE analysis study indicates that both Evans and Hintermann procedures have good corrective ability for AAFD. Compared to Evans, Hintermann procedure can provide a stronger corrective effect while causing greater disturbance to the biomechanics of Chopart joints, which may be an important mechanismof arthritis. Nevertheless, it yields a better protection to the subtalar joint than Evans osteotomy. Both Evans and Hintermann LCL surgeries have a considerable impact on adjacent joints and ligament tissues. Such effects alongside the overcorrection problem should be cautiously considered when choosing the specific surgical method. Level III, case-control study.

A novel histologic description of the fibrous networks in the lid-cheek junction and infraorbital region.

The aim of this study was to identify the anatomical feature of retaining ligament and fat compartment on the lower eyelid and infraorbital region using a histological method, and to investigate clear definitions for them which could be used generally in the clinical area. Eighteen specimens from eight fresh Korean cadavers were stained with Masson trichrome or hematoxylin and eosin. The ligamentous and fascial fibrous tissue were clearly identified. The ligamentous fibrous tissue which traversed in the superficial and deep fat layer was skin ligament and orbicularis retaining ligament (ORL). The fascial fibrous tissue enclosed the orbicularis oculi muscle (OOc) and circumferencial adipose tissue. Based on the ligamentous and fascial structure, three fat compartments, septal, suborbicularis oculi and infraorbital fat compartment, could be identified. The OOc attached to orbital rim and dermis by ORL and skin ligament, and the muscle fascicle and fat fascicle provided the connection point to the ORL and skin ligament as enclosing all muscle and fat tissue. The combination of the force made by the skin ligament in the lower eyelid and ORL may decide the level and form of the infraorbital grooves.

Platelet-rich plasma - a revolutionary therapeutic option in multi-disciplinary indications

Background: Platelet-rich plasma (PRP) was originally described as a small volume of plasma that contains higher concentrations of platelets, compared to peripheral blood. Although currently the use of PRP in most indications is off-label, it is not prohibited. Initially, PRP was used for wound healing and tissue regeneration in fields such as orthopaedics, dermatology, maxillofacial surgery and dentistry.
 Aim of the study: The aim of this article was to present and summarise the modern production methods, the mechanism of action at the molecular and biochemical level and the most important uses and indications of PRP in present-day medicine.
 Material and methods: A cross-sectional search of relevant literature was performed in databases using accepted wording. Publications from 2003-2023 were included. The entire process has been supplemented with additional procedures to increase the reliability of this publication.
 Results: Orthopaedics has gained many minimally invasive therapeutic solutions thanks to PRP. Its effects on ligament and tendon tissues have been studied, where promising data have been proven. Also in aesthetic medicine and dermatology, many treatment strategies have been developed using PRP, mainly for the treatment of acne, androgenic alopecia and delaying tissue ageing as much as possible.
 Conclusion: Platelet-rich plasma has found application in the treatment of many conditions in orthopaedics, dermatology, aesthetic medicine and dentistry. It is characterised by good therapeutic efficacy, with relatively low risk. However, high-quality studies are still lacking to provide more reliable data.

Multiomics analysis of cultured mouse periodontal ligament cell-derived extracellular matrix

A comprehensive understanding of the extracellular matrix (ECM) is essential for developing biomimetic ECM scaffolds for tissue regeneration. As the periodontal ligament cell (PDLC)-derived ECM has shown potential for periodontal tissue regeneration, it is vital to gain a deeper understanding of its comprehensive profile. Although the PDLC-derived ECM exhibits extracellular environment similar to that of periodontal ligament (PDL) tissue, details of its molecular composition are lacking. Thus, using a multiomics approach, we systematically analyzed cultured mouse PDLC-derived ECM and compared it to mouse PDL tissue as a reference. Proteomic analysis revealed that, compared to PDL tissue, the cultured PDLC-derived ECM had a lower proportion of fibrillar collagens with increased levels of glycoprotein, corresponding to an immature ECM status. The gene expression signature was maintained in cultured PDLCs and was similar to that in cells from PDL tissues, with additional characteristics representative of naturally occurring progenitor cells. A combination of proteomic and transcriptomic analyses revealed that the cultured mouse PDLC-derived ECM has multiple advantages in tissue regeneration, providing an extracellular environment that closely mimics the environment in the native PDL tissue. These findings provide valuable insights for understanding PDLC-derived ECM and should contribute to the development of biomimetic ECM scaffolds for reliable periodontal tissue regeneration.

Postoperative healing and complications based on anterior cruciate ligament reconstruction graft type.

Injury to the anterior cruciate ligament (ACL) is a devastating injury to athletes of all ages. The current gold standard treatment following complete rupture of the ACL is reconstruction of the torn ligament with autograft or allograft tendon. Commonly used tendon grafts include patellar tendon, hamstring tendon, and quadriceps tendon. Although ligaments and tendons have similar collagen and proteoglycan compositions, they maintain a unique composition and arrangement of cells to serve their unique biomechanical needs. Therefore, following ACL reconstruction (ACLR), the implanted tendon tissue undergoes a process of remodeling which is termed "ligamentization". The process of ligamentization is divided into three main phases, which include the early healing phase, the proliferative phase, and the maturation phase. Following the process of ligamentization, the graft tissue closely mimics the appearance of ligament tissue on an ultrastructural level. Successful outcome following ACLR is contingent upon adequate remodeling of the tissue as well as healing of the graft within the bone tunnels in the femur and tibia. Choice of graft has individual implications regarding their associated risk of complications, failure, and infection. The purpose of this review is to summarize the process of ligamentization and graft healing and to discuss how graft type influences the rate and types of complications, failures, and infections.

Effect of Cells Derived from Periodontal Ligament Tissue on Bone Formation.

Recent reports indicate that sclerostin is secreted by periodontal ligament tissue-derived (PDL) cells during orthodontic force loading and that the secreted sclerostin contributes to bone metabolism. However, the detailed mechanism is poorly understood. The aim of this study was to determine how PDL cells affect bone formation. Rat periodontal ligament tissue was immunohistochemically stained for sclerostin. Cultured primary PDL cells, osteoblasts, and skin fibroblasts (Sfbs) isolated from rat periodontal ligament tissue, calvaria, and skin, respectively, were examined. Osteoblasts were cultured with control conditioned medium (Cont-CDM) and PDL cell culture conditioned medium (PDL-CDM) for up to 21 days. Cultured osteoblasts were then stained with alkaline phosphatase and von Kossa stain. Osteoblasts cultured in each conditioned medium were analyzed by real-time quantitative PCR for bone Gla protein (Bgp), Axin2, and Ki67 expression. PDL cells used to obtain conditioned medium were analyzed for Sost, Ectodin and Wnt1 expression and compared with expression in Sfbs. Expression of sclerostin was observed in periodontal ligament tissue by immunohistochemical staining. The formation of mineralization nodules was inhibited in PDL-CDM compared with Cont-CDM in osteoblast culture. In PDL-CDM, the expression levels of Bgp and Axin2 in osteoblasts were decreased compared with Cont-CDM. In PDL cells, expression levels of Sost and Ectodin were much higher than in Sfbs; however, expression of Wnt1 was lower in PDL cells compared with Sfbs. PDL cells secrete various proteins, including sclerostin and suppress osteogenesis in osteoblasts through the canonical Wnt pathway.

Canal of Nuck hernia: A Case Report and Literature Review

Background: The canal of Nuck represents an anatomical remnant in females, resulting from incomplete closure of the processus vaginalis during embryonic development. It can lead to various clinical entities such as hernias and hydroceles, necessitating prompt recognition and management to prevent serious complications. Case Presentation: We present a case of a 24-year-old female with a longstanding history of right inguinal swelling associated with intermittent lower abdominal pain. Initial physical examination and imaging studies revealed findings consistent with a canal of Nuck hydrocele. Despite conservative management, persistent symptoms prompted surgical intervention. Intraoperatively, the canal contained round ligament tissue, confirming the diagnosis of a canal of Nuck hernia. The patient underwent successful hernia sac excision with mesh application and had an uneventful postoperative course. Conclusion: Canal of Nuck hernias are rare but can present with chronic symptoms and potentially serious complications such as incarceration or strangulation. Timely diagnosis using imaging modalities such as ultrasound and MRI is crucial for appropriate management, often requiring surgical intervention to alleviate symptoms and prevent recurrence.

Circ_0087199 depletion attenuates lipopolysaccharides-induced human periodontal ligament cell injury through the miR-527/TLR4 axis.

Circular RNAs participate in the development of periodontitis. The present work aims to reveal the role and mechanism of circ_0087199 in human periodontal ligament cell (PDLC) injury during periodontitis. PDLCs were treated with lipopolysaccharides (LPS) to establish a periodontitis cell model. Quantitative real-time polymerase chain reaction was used to detect the expression of circ_0087199, miR-527, toll-like receptor 4 (TLR4). Western blot analysis assay was performed to assess protein expression. Cell viability, proliferation, apoptosis and inflammation were investigated by cell counting kit-8, EdU assay, flow cytometry and enzyme-linked immunosorbent assay, respectively. Oxidative stress was evaluated by malondialdehyde assay kit and superoxide dismutase activity assay kit. The interaction between miR-527 and circ_0087199 or TLR4 was confirmed by a dual-luciferase reporter assay. Circ_0087199 and TLR4 expression levels were significantly increased, while miR-527 was decreased in the periodontal ligament tissues of periodontitis patients and LPS-stimulated PDLCs when compared with controls. LPS treatment inhibited cell viability and proliferation but induced cell apoptosis, inflammation and oxidative stress, whereas these effects were attenuated after circ_0087199 knockdown. Circ_0087199 bound to miR-527 and regulated LPS-caused PDLC damage by targeting miR-527. Additionally, the overexpression of TLR4, a target gene of miR-527, rescued miR-527 mimic-mediated effects on LPS-treated PDLCs. Further, the regulation of circ_0087199 toward TLR4 involved miR-527. Circ_0087199 knockdown attenuated LPS-induced apoptosis, inflammation and oxidative stress of PDLCs by regulating the miR-527/TLR4 pathway.

Fetus in Ovary, Balloon in Uterus: A Serious Missed Diagnosis

Ovarian ectopic pregnancy is one of the non-tubal ectopic pregnancies. It is a very rare, with an estimated incidence of 1/7000-1/40,000 live births and 0.5- 3% of all ectopic Pregnancies. In primary ovarian pregnancy, ovum is fertilized within the follicle itself before being released. Spiegelberg criteria for the diagnosis of ovarian pregnancy are Tube on the involved site should be intact, Gestational sac has to be located in the ovary, The ectopic pregnancy has to be connected to the uterus by the uteroovarian ligament and Ovarian tissue in the wall of the gestational sac should be proven by histopathology. Ovarian Follicle can accommodate the expanding ectopic gestation more readily than the tube but 75% of ovarian gestation rupture in the early first trimester and are usually misdiagnosed as corpus luteal haemorrhage. Advanced ovarian pregnancies with fetal death have been reported. 91% of OEP rupture before the end of 1st trimester. we present a case of Ovarian Ectopic Pregnancy, who reported to our hospital as failed termination of early pregnancy and ongoing second attempt of termination. USG detected a gestational sac with a live fetus of 12 weeks behind the uterus and a foley’s catheter balloon in empty uterine cavity. Subsequently confirmed at surgery as ovarian pregnancy. and proven by histopathology.

Sustained delivery of chemically modified mRNA encoding amelogenin from self-assembling hydrogels for periodontal regeneration

Periodontitis is a growing clinical problem worldwide. Despite various approaches that have been devoted to repairing periodontal defects, the clinical outcomes are still limited due to the decline in tissue regenerative potential after periodontitis. Fortunately, chemically modified mRNA (modRNA)-based therapeutics have emerged as a promising strategy to combat incurable diseases. However, the use of modRNA for treating periodontitis is rare and challenging. Herein, a novel therapeutic mRNA platform that allows for sustained delivery and targeted osteogenesis and cementogenesis was developed for periodontal regeneration by combining a self-assembling PLA-PEG-PLA hydrogel and newly synthesized modRNA encoding amelogenin (AMELX) via in vitro transcription. The thermosensitive PLA-PEG-PLA hydrogel significantly prevented modRNA degradation and prolonged the release of encapsulated modRNA by forming an in situ hydrogel depot at 37 °C, resulting in sustained and strong expression of AMELX in human periodontal ligament stem cells (PDLSCs). Moreover, the AMELX modRNA exhibited a great capacity for promoting osteogenesis and cementogenesis of PDLSCs, as evidenced by elevated alkaline phosphatase (ALP) activity, calcium nodule formation, and osteogenesis- and cementogenesis-related gene expression (e.g., ALP, BMP2, CAP, BSP, COL1A1). As a result, after a single local injection, the PLA-PEG-PLA hydrogel enabled AMELX modRNA to persist and release at the defect site, thus successfully regenerating bone and periodontal ligament tissues in periodontal defects of rats. These findings provide a new approach for treating periodontal defects using self-assembling hydrogels to enable safe and effective delivery of AMELX modRNA, thereby offering various possibilities for functional tissue reconstruction with mRNA therapeutics.

The mechanism of adipose mesenchymal stem cells to stabilize the immune microenvironment of pelvic floor injury by regulating pyroptosis and promoting tissue repair

Pelvic organ prolapse (POP) has a high incidence rate among Chinese women. Repeated mechanical stimulation is an important factor causing POP, but the injury mechanism has not yet been elucidated. The purpose of this study is to explore the related mechanisms of pelvic floor supporting tissue damage caused by mechanical force and the application of stem cell therapy. First, we obtained vaginal wall and sacral ligament tissue samples from clinical patients for examination. Pelvic floor support tissues of POP patients displayed high expression of inflammation and immune disorders. Then, we constructed a rat model of childbirth injury. In vivo and in vitro experiments investigated the key mechanism of pelvic floor support tissue injury caused by mechanical force. We discovered that after mechanical force, a large number of reactive oxygen species (ROS) and macrophages rapidly accumulated in pelvic floor tissues. ROS stimulated macrophages to produce NLRP3 inflammatory complex, induced the release of interleukin (IL-1β) and pyroptosis and exacerbated the inflammatory state of damaged tissues, persisting chronic inflammation of fibroblasts in supporting tissues, thus causing the pelvic floor's extracellular matrix (ECM) collagen metabolic disorder. Resultingly impeding the repair process, thereby causing the onset and progression of the disease. Through their paracrine ability, we discovered that adipose mesenchymal stem cells (ADSCs) could inhibit this series of pathological processes and promote tissue repair, asserting a good therapeutic effect. Simultaneously, to overcome the low cell survival rate and poor therapeutic effect of directly injecting cells, we developed a ROS-responsive PVA@COLI hydrogel with ADSCs. The ROS-scavenging properties of the gel could reshape the site of inflammation injury, enhance cell survival, and play a role in subsequent treatment. The findings of this study could serve as a basis for early, targeted intervention therapy for POP and representing a promising approach.

Research on Runx2 gene induced differentiation of human amniotic mesenchymal stem cells into ligament fibroblasts in vitro and promotion of tendon-bone healing in rabbits

To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts in vitro and promote the tendon-bone healing in rabbits. hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues. Flow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection ( P<0.05), Fibronectin significantly increased at 3 days ( P<0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days ( P<0.05). CCK-8 detection showed that there was no significant difference ( P>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups. Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.

Developmental endothelial locus-1 promotes osteogenic differentiation and alveolar bone regeneration in experimental periodontitis with type 2 diabetes mellitus.

This study sought to explore the role of developmental endothelial locus-1 (DEL-1) in osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) and investigate the therapeutic effect of DEL-1 in ligature-induced experimental periodontitis with type 2 diabetes mellitus (T2DM). T2DM is a significant risk factor for periodontitis. Treatment modalities for periodontitis with T2DM are being explored. DEL-1 is a versatile protein that can modulate the different stages of inflammatory diseases including periodontitis. The direct effect of DEL-1 on osteogenic differentiation of PDLSCs in periodontitis with T2DM is poorly understood. Primary hPDLSCs were isolated from periodontal ligament tissue and identified by flow cytometry. In osteogenesis experiments, alkaline phosphatase (ALP), Alizarin Red staining and western blot were used to assess the osteogenic effect of DEL-1 on hPDLSCs in high glucose and inflammation environments. The mouse model of ligature-induced experimental periodontitis was established. H&E and Masson's trichrome staining were used to assess the change of periodontal tissue after local periodontal injection of DEL-1. Immunohistochemical staining was used to evaluate osteogenic-related protein expression. hPDLSCs expressed mesenchymal stem cell (MSC)-specific surface markers and were negative for hematopoietic cell surface markers. hPDLSCs had the potential for multidirectional differentiation. DEL-1 could enhance the osteogenic differentiation of hPDLSCs in high glucose and inflammation environments, although it did not return to the control level. Histological staining showed that DEL-1 contributed to alveolar bone regeneration and osteogenic-related protein expression, but the degree of improvement in T2DM mice was lower than in non-T2DM mice. In summary, we demonstrated that DEL-1 could promote osteogenic differentiation of hPDLSCs in high glucose and inflammation environment and rescue alveolar bone loss in experimental periodontitis with T2DM, which could provide a novel therapeutic target for periodontitis with T2DM.

The alteration of apoptosis-related genes in female pelvic supportive tissues with regard to menopausal status

PurposeWe aimed to compare the expression levels of anti-apoptotic and proapoptotic genes in the parametrium, sacrouterine and round ligaments with respect to menopausal status in women presenting without any indication of pelvic organ prolapse (POP). We hypothesized that apoptosis related gene expressions in female pelvic tissues may be altered during menopause.MethodsThe study groups consisted of pre-menopausal (n = 10) and menopausal (n = 10) females who did not have POP symptoms. Three different types of tissue samples (Parametrium, Round Ligament and Sacrouterine Ligament) were obtained and RNA was isolated from these tissues. After purifying and quantifying RNA samples, qPCR was used to determine the expression levels of anti-apoptotic and pro-apoptotic genes.ResultsBCL-2 gene expression levels were significantly lower in all the tissues of menopausal patients compared to those of premenopausal patients. In comparison to premenopausal patients, the sacrouterine ligament tissue BAD expression level was significantly high (p = 0.035), and the BCL-2/BAD ratio was significantly lower in menopausal patients (p = 0.006).ConclusionApoptosis-related protein levels change during menopause; pro-apoptotic gene expressions decrease and anti-apoptotic gene expressions increase. The significant alteration of BCL-2 and BAD expression in sacrouterine ligament with respect to menopausal status was observed and this suggested that when compared to other pelvic tissues, the sacrouterine ligament, which plays a crucial role for genital organs in restoring normal pelvic anatomy and providing support, could be affected more by menopause.

Leucine-Rich Repeat Containing 15-Mediated Cell Adhesion Is Essential for Integrin Signaling in TGF-β1-Induced PDL Fibroblastic Differentiation.

Human periodontal ligament cells (hPDLCs) cultured from periodontal ligament (PDL) tissue contain postnatal stem cells that can be differentiated into PDL fibroblasts. We obtained PDL fibroblasts from hPDLCs by treatment with low concentrations of TGF-β1. Since the extracellular matrix and cell surface molecules play an important role in differentiation, we had previously developed a series of monoclonal antibodies against PDL fibroblast-specific cell surface molecules. One of these, the anti-PDL51 antibody, recognized a protein that was significantly upregulated in TGF-β1-induced PDL fibroblasts and highly accumulated in the PDL region of the tooth root. Mass spectrometry revealed that the antigen recognized by the anti-PDL51 antibody was leucine-rich repeat containing 15 (LRRC15), and this antibody specifically recognized the extracellular glycosylated moiety of LRRC15. Experiments presented here show that as fibroblastic differentiation progresses, increased amounts of LRRC15 localized at the cell surface and membrane. Inhibition of LRRC15 by siRNA-mediated depletion and by antibody blocking resulted in downregulation of the representative PDL fibroblastic markers. Moreover, following LRRC15 inhibition, the directed and elongated cell phenotypes disappeared, and the long processes of the end of the cell body were no longer found. Through a specific interaction between integrin β1 and LRRC15, the focal adhesion kinase signaling pathway was activated in PDL fibroblasts. Furthermore, it was shown that increased LRRC15 was important for the activation of the integrin-mediated cell adhesion signal pathway for regulation of cellular functions, including fibroblastic differentiation, proliferation, and cell migration arising from the expression of PDL-related genes in TGF-β1-induced PDL fibroblastic differentiation.

LRP1-deficient leptin receptor-positive cells in periodontal ligament tissue reduce alveolar bone mass by inhibiting bone formation

ObjectiveLeptin receptor-positive (LepR+) periodontal ligament (PDL) cells play a crucial role in osteogenesis during tooth socket healing and orthodontic tooth movement; however, the factors regulating osteoblast differentiation remain unclear. This study aimed to demonstrate the function of low-density lipoprotein receptor-related protein 1 (LRP1) in alveolar bone formation by examining conditional knockout (cKO) mice lacking LRP1 in LepR+ cells. DesignBone mass and formation were examined via bone morphometric analysis. Bone formation and resorption activities were determined via histochemical staining. Additionally, PDL cells collected from molars were induced to differentiate into osteoblasts with the addition of BMP2 and to mineralize with the addition of osteogenic medium. Osteoblast differentiation of PDL cells was examined by measuring the expression of osteoblast markers. ResultsBone morphometry analysis revealed decreased mineral apposition rate and alveolar bone mass in cKO mice. Additionally, cKO mice showed a decreased number of osterix-positive cells in the PDL. cKO mice had a large number of osteoclasts around the alveolar bone near the root apex and mesial surface of the tooth. In the PDL cells from cKO mice, inhibition of mineralized matrix formation and decreased expression of alkaline phosphatase, osterix, bone sialoprotein, and osteocalcin were observed even when BMP2 was added to the medium. BMP2, BMP4, and osteoprotegerin expression also decreased, but RANKL expression increased dominantly. ConclusionLRP1 in LepR+ cells promotes bone formation by stimulating osteoblast differentiation. Our findings can contribute to clinical research on bone diseases and help elucidate bone metabolism in the periodontal tissue.

Polycaprolactone Composites/Blends and Their Applications Especially in Water Treatment

Biodegradable poly(ɛ-caprolactone) (PCL) and its composites or blends have received a lot of attention in the last decade because of their potential applications in human life and environmental remediation. Greater efforts have been made to develop biodegradable chemical materials as adsorbents that do not pollute the environment in order to replace traditional materials. Among the numerous types of degradable materials, PCL is currently the most promising, the most popular, and the best material to be developed, and it is referred to as a “green” eco-friendly material. Membranes and adsorbents for water treatment, packaging and compost bags, controlled drug carriers, and biomaterials for tissues such as bone, cartilage, ligament, skeletal muscle, skin, cardiovascular and nerve tissues are just some of the applications of this biodegradable polymer (PCL). The goal of this review is to present a brief overview of PCL, syntheses of PCL, its properties, PCL composites, and PCL blends and to provide a detailed investigation into the utility of PCL/PCL-based adsorbing agents in the removal of dyes/heavy metal ions. Overall, it can be confirmed that PCL blends and composites were found to be significant competitors to other well-known adsorbents in the treatment of wastewaters, necessitating a thorough investigation of their manufacture.

A comparative study of the anatomy and MRI images of the lumbar foraminal ligaments at the L1-L5 levels.

The purpose of this study was to evaluate the ability of MRI images to reveal foraminal ligaments at levels L1-L5 by comparing the results with those of anatomical studies. Eighty lumbar foramina were studied. First, the best MRI scanning parameters were selected, and the transverse and sagittal axes of each lumbar foramina were scanned to identify and record the ligament-like structures in each lumbar foramen. Then, the cadaveric specimens were anatomically studied, and all ligament structures in the lumbar foramina were retained. The number, morphology and distribution of ligaments under anatomical and MRI scanning were observed. Histological staining of the dissected ligament structures was performed to confirm that they were ligamentous tissues. Finally, the accuracy of ligament recognition in MRI images was statistically analyzed. A total of 233 foraminal ligaments were identified in 80 lumbar intervertebral foramina through cadaveric anatomy. The radiating ligaments (176, 75.5%) were found to be attached from the nerve root to the surrounding osseous structures, while the transforaminal ligaments (57, 24.5%) traversed the intervertebral foramina without any connection to the nerve roots. A total of 42 transforaminal ligament signals and 100 radiating ligament signals were detected in the MRI images of the 80 intervertebral foramina. The MRI can identify the lumbar foraminal ligament, and the recognition rate of the transforaminal ligament is higher than that of the radiating ligament. This study provides a new method for the clinical diagnosis of the relationship between the lumbar foraminal ligament and radicular pain.

A Post-traumatic Cyclops Lesion Arising from Posterior Cruciate Ligament Injury with Loss of Extension: A Case Report

Introduction: Cyclops lesions or arthrofibrotic nodules of the knee, first described by Jackson and Schaefer, occur in the anterior aspect of the intercondylar notch. Arthroscopically, they appear as head-like fibrous lesions with reddish-blue discoloration areas and consist of a pedunculated nodule of fibrovascular proliferative tissue, with or without bone or cartilaginous tissue. The cyclops lesion is a localized arthrofibrotic nodule most commonly seen following anterior cruciate ligament (ACL) reconstruction but rare on posterior cruciate ligament injuries (PCL). In this study, we present a novel case of cyclops lesion from a minor PCL injury without laxity or previous surgery. Case Presentation: A 37-year-old man visited the outpatient clinic complaining of mild knee pain, intermittent locking, and extension discomfort after minor trauma. These symptoms started 3 weeks prior, during his usual baseball activity. The magnetic resonance imaging (MRI) showed an intact ACL. Still, it had a partially injured PCL, a small suprapatellar effusion, and a cyclops lesion (2.4 × 3.4 × 2.5 cm) in the intercondylar notch of the femur, originating from the PCL. An arthroscopy confirmed and excised a cyclops lesion originating from the PCL. The microscopic findings included congested blood vessels of irregular-sized veins and hemorrhagic necrosis within the wavy ligament tissues, which confirmed its origin from the ligament tissue. After arthroscopic excision, the patient’s symptoms were relieved without laxity. Conclusions: While most of these lesions can be treated efficiently by arthroscopy, the differential diagnosis should be performed for unique cases with a lesion from minor PCL injury without laxity or previous surgery.

Local application of gingiva-derived mesenchymal stem cells on experimental periodontitis in rats.

Stem cell-based approaches in regenerative periodontal therapy have been used in different experimental models. In this study, the effect of local application of gingival mesenchymal stem cells (GMSC) in fibroin/chitosan oligosaccharide lactate hydrogel (F/COS) on periodontal regeneration was evaluated using experimental periodontitis model in rats. Mesenchymal stem cells were isolated from the gingiva of rats and characterized. Viability tests and confocal imaging of GMSC in hydrogels were performed. Healthy control without periodontitis (Health; H; n=10), control with periodontitis but no application (Periodontitis; P; n=10), only hydrogel application (F/COS; n=10), and GMSC+F/COS (n=10) four groups were formed for in vivo studies. Experimental periodontitis was created with silk sutures around the maxillary second molars. GMSC labeled with green fluorescent protein (GFP) (250,000 cells/50μL) in F/COS were applied to the defect. Animals were sacrificed at 2nd and 8th weeks and maxillae of the animals were evaluated by micro-computed tomography (micro-CT) and histologically. The presence of GFP-labeled GMSC was confirmed at the end of 8weeks. Micro-CT analysis showed statistically significant new bone formation in the F/COS+GMSC treated group compared with the P group at the end of 8weeks (p<0.05). New bone formation was also observed in the F/COS group, but the statistical analysis revealed that this difference was not significant when compared with the P group (p>0.05). Long junctional epithelium formation was less in the F/COS+GMSC group compared with the P group. Periodontal ligament and connective tissue were well-organized in F/COS+GMSC group. The results showed that local GMSC application in hydrogel contributed to the formation of new periodontal ligament and alveolar bone in rats with experimental periodontitis. Since gingiva is easly accessible tissue, it is promising for autologous cell-based treatments in clinical applications.