Crosstalk between Wnt and bone morphogenetic protein signaling during osteogenic differentiati

Mesenchymal stem cells(MSCs)originate from many sources,including the bone marrow and adipose tissue,and differentiate into various cell types,such as osteoblasts and adipocytes.Recent studies on MSCs have revealed that many transcription factors and signaling pathways control osteogenic development.Osteogenesis is the process by which new bones are formed;it also aids in bone remodeling.Wnt/β-catenin and bone morphogenetic protein(BMP)signaling pathways are involved in many cellular processes and considered to be essential for life.Wnt/β-catenin and BMPs are important for bone formation in mammalian development and various regulatory activities in the body.Recent studies have indicated that these two signaling pathways contribute to osteogenic differen-tiation.Active Wnt signaling pathway promotes osteogenesis by activating the downstream targets of the BMP signaling pathway.Here,we briefly review the molecular processes underlying the crosstalk between these two pathways and explain their participation in osteogenic differentiation,emphasizing the canonical pathways.This review also discusses the crosstalk mechanisms of Wnt/BMP signaling with Notch-and extracellular-regulated kinases in osteogenic differentiation and bone development.

Icariin accelerates bone regeneration by inducing osteogenesisangiogenesis coupling in rats with type 1 diabetes mellitus

BACKGROUND Icariin(ICA),a natural flavonoid compound monomer,has multiple pharmacological activities.However,its effect on bone defect in the context of type 1 diabetes mellitus(T1DM)has not yet been examined.AIM To explore the role and potential mechanism of ICA on bone defect in the context of T1DM.METHODS The effects of ICA on osteogenesis and angiogenesis were evaluated by alkaline phosphatase staining,alizarin red S staining,quantitative real-time polymerase chain reaction,Western blot,and immunofluorescence.Angiogenesis-related assays were conducted to investigate the relationship between osteogenesis and angiogenesis.A bone defect model was established in T1DM rats.The model rats were then treated with ICA or placebo and micron-scale computed tomography,histomorphometry,histology,and sequential fluorescent labeling were used to evaluate the effect of ICA on bone formation in the defect area.RESULTS ICA promoted bone marrow mesenchymal stem cell(BMSC)proliferation and osteogenic differentiation.The ICA treated-BMSCs showed higher expression levels of osteogenesis-related markers(alkaline phosphatase and osteocalcin)and angiogenesis-related markers(vascular endothelial growth factor A and platelet endothelial cell adhesion molecule 1)compared to the untreated group.ICA was also found to induce osteogenesis-angiogenesis coupling of BMSCs.In the bone defect model T1DM rats,ICA facilitated bone formation and CD31hiEMCNhi type H-positive capillary formation.Lastly,ICA effectively accelerated the rate of bone formation in the defect area.CONCLUSION ICA was able to accelerate bone regeneration in a T1DM rat model by inducing osteogenesis-angiogenesis coupling of BMSCs.

Hydrogel loaded with bone marrow stromal cell-derived exosomes promotes bone regeneration by inhibiting inflammatory responses and angiogenesis

BACKGROUND Bone healing is a complex process involving early inflammatory immune regu-lation,angiogenesis,osteogenic differentiation,and biomineralization.Fracture repair poses challenges for orthopedic surgeons,necessitating the search for efficient healing methods.AIM To investigate the underlying mechanism by which hydrogel-loaded exosomes derived from bone marrow mesenchymal stem cells(BMSCs)facilitate the process of fracture healing.METHODS Hydrogels and loaded BMSC-derived exosome(BMSC-exo)gels were charac-terized to validate their properties.In vitro evaluations were conducted to assess the impact of hydrogels on various stages of the healing process.Hydrogels could recruit macrophages and inhibit inflammatory responses,enhance of human umbilical vein endothelial cell angiogenesis,and promote the osteogenic differen-tiation of primary cranial osteoblasts.Furthermore,the effect of hydrogel on fracture healing was confirmed using a mouse fracture model.RESULTS The hydrogel effectively attenuated the inflammatory response during the initial repair stage and subsequently facilitated vascular migration,promoted the formation of large vessels,and enabled functional vascularization during bone repair.These effects were further validated in fracture models.CONCLUSION We successfully fabricated a hydrogel loaded with BMSC-exo that modulates macrophage polarization and angiogenesis to influence bone regeneration.

Low-intensity pulsed ultrasound reduces alveolar bone resorption during orthodontic treatment via Lamin A/C-Yes-associated protein axis in stem cells

BACKGROUND The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years,which also may lead to some complications such as alveolar bone resorption or tooth root resorption.Low-intensity pulsed ultrasound(LIPUS),a noninvasive physical therapy,has been shown to promote bone fracture healing.It is also reported that LIPUS could reduce the duration of orthodontic treatment;however,how LIPUS regulates the bone metabolism during the orthodontic treatment process is still unclear.AIM To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement(OTM)model and explore the underlying mechanisms.METHODS A rat model of OTM was established,and alveolar bone remodeling and tooth movement rate were evaluated via micro-computed tomography and staining of tissue sections.In vitro,human bone marrow mesenchymal stem cells(hBMSCs)were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction,Western blot,alkaline phosphatase(ALP)staining,and Alizarin red staining.The expression of Yes-associated protein(YAP1),the actin cytoskeleton,and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA(siRNA)application via immunofluorescence.RESULTS The force treatment inhibited the osteogenic differentiation potential of hBMSCs;moreover,the expression of osteogenesis markers,such as type 1 collagen(COL1),runt-related transcription factor 2,ALP,and osteocalcin(OCN),decreased.LIPUS could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by force.Mechanically,the expression of LaminA/C,F-actin,and YAP1 was downregulated after force treatment,which could be rescued by LIPUS.Moreover,the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA treatment.Consistently,LIPUS increased alveolar bone density and decreased vertical bone absorption in vivo.The decreased expression of COL1,OCN,and YAP1 on the compression side of the alveolar bone was partially rescued by LIPUS.CONCLUSION LIPUS can accelerate tooth movement and reduce alveolar bone resorption by modulating the cytoskeleton-Lamin A/C-YAP axis,which may be a promising strategy to reduce the orthodontic treatment process.

Indication and surgical approach for reconstruction with endoprosthesis in bone-associated soft tissue sarcomas:Appropriate case management is vital

It is important for surgeons performing sarcoma surgery to know that bone resection and tumor prosthesis applications in soft tissue sarcomas(STS)have unique features in terms of indication,surgical approach and follow-up,in terms of the management of these cases.Some STS are associated with bone and major neurovascular structures.Bone-associated STS are generally relatively large and relatively deep-seated.Additionally,the tendency for metastasis is high.In some cases,the decision about which structures to resect is difficult.These cases are often accompanied by poor oncological and surgical outcomes.Management of cases should be done by a multidisciplinary team in advanced centers specialized in this field.The surgical team must have sufficient knowledge and experience in the field of limb-sparing surgery.Preoperative evaluation and especially good planning of bone and soft tissue reconstruction are vital.

Unveiling the role of hypoxia-inducible factor 2alpha in osteoporosis:Implications for bone health

BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing osteogenesis.In the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic environment.Recently,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been determined.AIM To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of OP.METHODS Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo experiments.Bone quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone treatment.Moreover,the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes.In vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic differentiation.Finally,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor rapamycin.RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions.In vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes.The opposite effects were shown for mouse BMSCs treated with the HIF-2αinhibitor PT2399.The mTOR inhibitor rapamycin was used to confirm that HIF-2αregulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway.Consequently,there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice.CONCLUSION Our study showed that inhibition of HIF-2αdecreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche.

Gene expression analysis of cytokines and MMPs in melatonin and rhBMP-2 enhanced bone remodeling

BACKGROUND In the medical and dental fields,there is a need for studies of new therapeutic approaches for the treatment of bone defects that cause extensive bone loss.Melatonin may be an important endogenous biological factor for bone remodeling,and growth factors may enhance the repair process.AIM To evaluate the gene expression of cytokines(IL-1β,IL-6,IL-10 and TNF-α),markers of osteoclastogenesis(RANK,RANKL and OPG)and MMPs(MMP-1,MMP-2,MMP-8 and MMP-13)from the treatment of melatonin associated with an osteogenic membrane and rhBMP-2 on the recovery of a bone injury.METHODS Sixty-four rats were used and divided into 9 experimental groups and were formed according to the treatment carried out in the region of the bone lesion,which varied between the combination of 1,10 and 100μmol/L of melatonin.Gene Expression analysis was performed using real time-PCR by reading the concentration of total RNA and reverse transcription.RESULTS There were differences between groups when compared with clot or scaffold control,and improvement with a higher concentration of melatonin or rhBMP-2.The combination melatonin(1μg)with 5μg of rhBMP-2,using the guided bone regeneration technique,demonstrated some effects,albeit mild,on bone repair of critical bone defects.CONCLUSION This indicates that the approach for administering these substances needs to be reassessed,with the goal of ensuring their direct application to the affected area.Therefore,future research must be carried out,seeking to produce materials with these ideal characteristics.

Impacts of radiation therapy on quality of life and pain relief in patients with bone metastases

Bone metastases(BM)are a common complication in advanced cancer patients,significantly contributing to morbidity and mortality due to their ability to cause pain,fractures,and spinal cord compression.Radiation therapy(RT)is vital in managing these complications by targeting metastatic lesions to ease pain,improve mobility,and reduce the risk of skeletal-related events such as fractures.Evidence supports the effectiveness of RT in pain relief,showing its ability to provide significant palliation and lessen the need for opioid painkillers,thereby enhancing the overall quality of life(QoL)for patients with BM.However,optimizing RT outcomes involves considerations such as the choice of radiation technique,dose fractionation schedules,and the integration of supportive care measures to mitigate treatment-related side effects like fatigue and skin reactions.These factors highlight the importance of personalized treatment planning tailored to individual patient needs and tumor characteristics.This mini-review aims to provide comprehensive insights into the multifaceted impacts of RT on pain management and QoL enhancement in BM patients,with implications for refining clinical practices and advancing patient care through the synthesis of findings from various studies.

Ilizarov technique for treatment of a giant aneurysmal bone cyst at the distal femur:A case report

BACKGROUND Aneurysmal bone cyst(ABC)is a benign cystic of unknown etiology,characterized by multiple chambers and a high recurrence rate.Current treatment options include vascular embolization,surgical excision,curettage with cavity filling,sclerosing agent injection into the cavity,radiotherapy,and systemic drug therapy.Among these,surgical excision and curettage are the preferred treatment modalities.However,when the cyst reaches a large size,extensive removal of diseased tissue during surgery can hinder bone healing.In our department,we treated a case of a large ABC at the distal end of the femur in a child using the Ilizarov technique.The tumor was completely excised,and reconstruction was achieved through autologous femoral bone transfer.The follow-up at two years post-surgery indicated good results without tumor recurrence,and the growth and development of the child were essentially unaffected.CASE SUMMARY An 11-year-old boy was presented with an accidental fracture of his right leg.Despite having been examined at other hospitals,he had not received treatment.Given the potential for significant bone defects and the difficulty of the surgery,our doctors opted to use the Ilizarov technique to minimize harm to the patient.Upon admission,the patient underwent a needle biopsy and complete tumor resection-the Ilizarov technique assisted in the transport and reconstruction of the autologous femoral bone.Postoperatively,the patient exhibited regular followups,during which bone transport was gradually performed,and the external fixation frame was removed on time.Follow-up X-rays of the right lower limb displayed no tumor recurrence,with a normal appearance.Bone formation at the cutting site was satisfactory,and the union of the bone ends indicated good healing.After two years of follow-up,the patient had essentially returned to normal.CONCLUSION We successfully applied the Ilizarov technique to treat ABC,reducing the financial burden of patients and the pain of multiple surgeries.In cases where significant bone defects occur,the Ilizarov technique has demonstrated satisfactory therapeutic outcomes.

Spoon-assisted autologous particulate bone graft harvesting technique

Particulate bone plays a crucial role in various oral and maxillofacial surgical procedures,including reconstruction,implantation,and craniofacial surgery.Autologous bone and deproteinized bovine bone xenografts are the two primary resources used for such procedures,with the former demonstrating superior cost-effectiveness and reduced comorbidity rates,particularly in cases involving donor zones.However,a significant challenge lies in acquiring uniformly sized autologous particulate bone specimens,with existing tools often yielding coarse particles at a high cost.Consequently,commercial bone xenograft solutions are frequently favored despite lower standards.This technical note introduces a novel technique for swiftly,safely,and efficiently obtaining autologous particulate bone specimens.The procedure involves the use of a motor handpiece fitted with a micro drill and surgical spoon to collect the bone particles.The continuous irrigation with saline maintains a clear surgical field during the milling process.The collected bone particles are then transferred to a metal capsule for further use.This technique offers a promising solution to the challenge of inconsistent particle size associated with harvesting using traditional methods,providing surgeons with a reliable and efficient method of obtaining autologous particulate bone samples.

Influence of Statins and Fibrates Drugs on Bone Health and Regeneration

In the medical and dental field, the importance and need for the study of materials and drugs for use as bone grafts or regeneration in injured areas due to the presence of fractures, infections or tumors that cause extensive loss of bone tissue is observed. Bone is a specialized, vascularized and dynamic connective tissue that changes throughout the life of the organism. When injured, it has a unique ability to regenerate and repair without the presence of scars, but in some situations, due to the size of the defect, the bone tissue does not regenerate completely. Thus, due to its importance, there is a great development in therapeutic approaches for the treatment of bone defects through studies that include autografts, allografts and artificial materials used alone or in association with bone grafts. Pharmaceuticals composed of biomaterials and osteogenic active substances have been extensively studied because they provide potential for tissue regeneration and new strategies for the treatment of bone defects. Statins work as specific inhibitors of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMG-CoAreductase). They represent efficient drugs in lowering cholesterol, as they reduce platelet aggregation and thrombus deposition;in addition, they promote angiogenesis, reduce the β-amyloid peptide related to Alzheimer’s disease and suppress the activation of T lymphocytes. Furthermore, these substances have been used in the treatment of hypercholesterolemia and coronary artery disease. By inhibiting HMG-CoAreductase, statins not only inhibit cholesterol synthesis, but also exhibit several other beneficial pleiotropic effects. Therefore, there has been increasing interest in researching the effects of statins, including Simvastatin, on bone and osteometabolic diseases. However, statins in high doses cause inflammation in bone defects and inhibit osteoblastic differentiation, negatively contributing to bone repair. Thus, different types of studies with different concentrations of statins have been studied to positively or negatively correlate this drug with bone regeneration. In this review we will address the positive, negative or neutral effects of statins in relation to bone defects providing a comprehensive understanding of their application. Finally, we will discuss a variety of statin-based drugs and the ideal dose through a theoretical basis with preclinical, clinical and laboratory work in order to promote the repair of bone defects.

Epdemiology and Treatment of Pseudarthrosis of Long Bones in the Servce D Orthopedics-Traumatology of the University Hospital of Donka

Introduction: Pseudarthrosis (PSA) of the diaphysis of long bones still remains a current problem, despite improvements in the treatment of these fractures. Our study aims to study the epidemiological and therapeutic aspects of PSA of the diaphysis of long bones. Method: This retrospective work concerns 30 cases of non-union of the diaphysis of long bones treated in the orthopedic and trauma surgery department at Donka National Hospital, during a period of 18 months from January 1, 2019 to June 30, 2020. Results: We recruited 30 patients, 80% of whom were male, with an average age of 39.9 years. Public road accidents (AVP) represented the main cause of fractures of the diaphysis of long bones 87%, they were open in 25 cases or 83%. The fractures were located in the middle 1/3 of the diaphysis of the long bones in 50% of cases. Treatment of initial fractures was traditional in 21 cases, orthopedic in 2 cases and surgical in 7 cases. It was aseptic nonunion in 28 cases (93%) and septic nonunion in 2 cases. They were hypertrophic in 7 cases, slightly hypertrophic in 5 cases, oligotrophic in 11 cases, atrophic in 6 cases and with bone defect in 1 case. The treatment was based on osteosynthesis including 16 cases of screwed “PV” plate: 7 cases of centromedullary “ECM” nailing, 2 cases of external fixator, 1 case of broaching and 4 cases of Plastering. The results according to ASAMI criteria on an anatomical level were excellent in 19 cases, good in 3 cases and poor in 3 cases, with a union rate of 76%. And 5 patients undergoing consolidation. Conclusion: Based on the literature data and the experience of our department, the true treatment of PSA requires correct management of the initial fracture without forgetting the interest in preventing AVP which appears to be an element essential, making it possible to reduce the incidence of fractures of the diaphysis.

Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age

Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBSx, and along the direction parallel to the forearm, TBSy, were calculated respectively. The statistics of TBSx and TBSy were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBSy to TBSx and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBSx and TBSy was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age.

Contribution of Bone Scintigraphy in the Metastatic Extension Assessment of Prostate Cancer: A Study of 288 Cases in the Nuclear Medicine Department of Idrissa Pouye General Hospital, Dakar

Introduction: Prostate cancer is the most frequently diagnosed male malignancy and the fifth leading cause of cancer death in men worldwide. Since the advent of screening methods such as Prostate Specific Antigen (PSA) assay, digital rectal examination (DRE) and prostate biopsy, its incidence has increased significantly. The aim of our study was to analyse aspects of bone scintigraphy (BS) as part of the metastatic extension assessment of prostate cancer in Senegal. Patients and Methods: This was a retrospective descriptive and analytical study, running from January 1er 2022 to August 31 2023. Patients with histologically confirmed prostate cancer were included. Whole-body scans (WBS) were performed using a dual-head SPECT gamma camera (Mediso Nucline TM Spirit DH-V type), 3 hours after intravenous injection of 8 MBq/kg (555 to 740 MBq) of 99mTc-HMDP. Results: A total of 288 patients with a mean age of 68.37 ± 7.79 years were included. The median total PSA level was 97.6 ng/ml, with 144 patients having a level greater than or equal to 20 ng/ml. All patients had adenocarcinoma, and the Gleason score was available in 202 (70.13%) patients, 75.75% of whom had a score greater than or equal to 7. BS was contributory in 70.48% of cases, with 30.90% positive and 39.58% negative. The result was inconclusive in 85 patients (29.51%). The mean PSA for patients with a positive scan was 190.2 ng/ml and 40.6 ng/ml for those with a negative scan. Multiple metastatic lesions predominated (87.35% of cases). Metastatic lesions occurred preferentially in the axial skeleton, with a proportion of 68% versus 32% in the appendicular skeleton. Classification of bone metastases according to the SOLOWAY score revealed grade I (62.07%), grade II (35.63%) and grade IV (2.30%). Conclusion: In Senegal, prostate cancer is generally diagnosed in men of advanced age. The presence of bone metastases is frequent in its evolution, transforming a curable localized disease into a generalized disease with a compromised prognosis. Bone scintigraphy remains an essential part of the initial work-up and evaluation of response to treatment.

Demineralized Bone Matrix Fibers plus Allograft Bone for Multilevel Posterolateral Spine Fusion: A Game Changer?

Introduction: While autograft bone is the gold standard for multilevel posterolateral lumbar fusion, bone substitutes and graft extenders such as allograft bone, ceramics and demineralized bone matrix (DBM) have been used to avoid the morbidity and insufficient quantity associated with harvesting autologous bone. The primary objective of this retrospective study was to determine whether, in patients with increased risk of operative nonunion related to multilevel fusion, adding DBM fibers to mineralized bone allograft resulted in better fusion than using allograft alone. The secondary objectives were to evaluate how adding DBM fibers affects functional disability, low back pain, intraoperative blood loss and the nonunion rate. Methods: This retrospective study involved a chart review of consecutive patients who underwent multilevel lumbar spinal fusion and were operated on by a single surgeon. The patients were divided into two groups: 14 patients received mineralized bone allograft (control group) and 14 patients received a combination of mineralized bone allograft and DBM (experimental group). Patients were reviewed at a mean of 16.4 ± 2.2 months after surgery at which point CT scans were analyzed to determine whether fusion had occurred;Oswestry disability index (ODI) and pain were also evaluated. Results: A mean of 5 levels [min 2, max 13] were fused in these patients. Posterolateral fusion as defined by the Lenke classification was not significantly different between groups. The experimental DBM group had a significantly better composite fusion score than the control group (P Discussion: Adding DBM fibers to allograft bone during multilevel posterolateral spinal fusion was safe and produced better composite fusion than using allograft only as an autograft extender.

Impact of bisphosphonate treatment on bone mineral density after kidney transplant

BACKGROUND Mineral bone disease is associated with chronic kidney disease and persists after kidney transplantation.Immunosuppressive treatment contributes to the patho-genesis of this disease.Bisphosphonate treatments have shown positive but inde-finite results.AIM To evaluate the effectiveness and safety of bisphosphonate treatment on post kidney transplantation bone mineral density(BMD).METHODS We included kidney transplant recipients(KTRs)whose BMD was measured after the operation but before the initiation of treatment and their BMD was measured at least one year later.We also evaluated the BMD of KTRs using two valid mea-surements after transplantation who received no treatment(control group).RESULTS Out of 254 KTRs,62(39 men)were included in the study.Bisphosphonates were initiated in 35 KTRs in total(20 men),1.1±2.4 years after operation and for a period of 3.9±2.3 years while 27(19 men)received no treatment.BMD improved significantly in KTRs who received bisphosphonate treatments(from-2.29±1.07 to-1.66±1.09,P<0.0001).The control group showed a non-significant decrease in BMD after 4.2±1.4 years of follow-up after surgery.Kidney function was not affected by bisphosphonate treatment.In KTRs with established osteoporosis,active treatment had a similar and significant effect on those with osteopenia or normal bone mass.CONCLUSION In this retrospective study of KTRs receiving bisphosphonate treatment,we showed that active treatment is effective in preventing bone loss irrespective of baseline BMD.

U-Net Based Dual-Pooling Segmentation of Bone Metastases in Thoracic SPECT Bone Scintigrams

In order to enhance the performance of the CNN-based segmentation models for bone metastases, this study proposes a segmentation method that integrates dual-pooling, DAC, and RMP modules. The network consists of distinct feature encoding and decoding stages, with dual-pooling modules employed in encoding stages to maintain the background information needed for bone scintigrams diagnosis. Both the DAC and RMP modules are utilized in the bottleneck layer to address the multi-scale problem of metastatic lesions. Experimental evaluations on 306 clinical SPECT data have demonstrated that the proposed method showcases a substantial improvement in both DSC and Recall scores by 3.28% and 6.55% compared the baseline. Exhaustive case studies illustrate the superiority of the methodology.

Place of Bone Scintigraphy in the Assessment of Extension and Follow-Up of Breast Cancer in Senegal: Study of 165 Cases in the Nuclear Medicine Department of Idrissa Pouye General Hospital (Dakar)

Introduction: Breast cancer is the most common cancer in women worldwide, accounting for an estimated 22% of all female cancers. It is the leading cause of cancer mortality in women, almost all of which is due to metastases, with 73% of metastases occurring in the bone. In oncology, metastable technetium 99-labelled methylene bisphosphonate bone scintigraphy (BS) remains the standard examination for detecting and assessing the extent of bone metastases. The aim of this study was to assess the role of BS in the evaluation and follow-up of breast cancer in Senegal. Methodology: This was a retrospective study of breast cancer patients who underwent bone scintigraphy with 99mTc-HMDP in the nuclear medicine department of Idrissa Pouye General Hospital (IPGHO), from July 2009 to June 2022. Results: We enrolled 165 patients, mean age 46.79 years (27 - 87 years). BS was performed in 94.37% of cases for post-therapeutic monitoring and in 5.63% for pre-therapeutic assessment. Results were contributory in 131 patients (92.25%), of whom 72 cases (50.70%) were normal and 59 cases (41.55%) positive or presenting bone metastases;and non-contributory or doubtful in 11 cases (7.75%). Secondary bone locations were multiple in 57 cases (96.61%) and single or solitary in 2 cases (3.39%). The scintigraphic appearance of bone metastases was hyper-fixative in 58 cases (98.31%) and mixed in 1 case (1.69%). Bone lesions were quantified using the Soloway’s grading classification. Conclusion: BS with 99mTc-labelled bisphosphonates remains the examination of choice for skeletal exploration, in the detection and extension of bone metastases in breast cancer. Performance has been enhanced by the development of SPECT coupled with CT (SPECT-CT).

Development and Optimization of Universal Bone Conduction Hearing Spectacles

Background: Non-implantable bone anchored hearing devices (BCHDs) are utilized for patients with conductive or mixed hearing loss who are unsuitable for conventional hearing aids or have unresolved middle ear issues. These devices can be surgically implanted or attached using adhesive plates, dental sticks, elastic headbands, or bone conduction spectacles. Optimal fitting of bone conduction spectacles requires appropriate frame selection and contact pressure in the temporal and mastoid areas. The ANSI S3.6 and DIN EN ISO 389-3 standards recommend a contact area of approximately 1.75 cm2 and a maximum force of 5.4 N for effective sound transmission and comfort. Methods: This study aimed to evaluate the technical fit and mechanical stability of universal bone conduction hearing spectacles compared to established systems. A Sen-Pressure 02 thin-film sensor connected to an Arduino Uno R3 board measured contact force in the temporal and mastoid areas. Several BCHDs were tested, including the Bruckhoff la belle BC D50/70, Radioear B71 headset, Radioear B71 elastic headband, Cochlear Baha SoundArc M, and Cochlear Baha elastic headband, on a PVC artificial head, with data analyzed using ANOVA and LSD post hoc tests. Results: The la belle BC D50/70 spectacles showed comparable contact force to established BCHDs, ensuring adequate sound transmission and comfort. Significant differences were observed between the systems, with the Radioear B71 headset exhibiting the highest forces. The la belle BC D50/70 had similar forces to the Radioear B71 elastic headband. Conclusion: The la belle BC D50/70 universal bone conduction hearing spectacles are a technically equivalent alternative to established BCHDs, maintaining pressure below 5.4 N. Future research should explore the impact of different contact forces on performance and comfort, and the integration of force control in modified spectacles. This study indicates that the la belle BC D50/70 is a viable alternative that meets audiological practice requirements.

Research Progress on the Bone Metastasis Mechanism of Prostate Cancer and Bone-Targeted Drugs

Prostate cancer is a common male malignant tumor,and bone metastasis is one of the common complications in the late stage of prostate cancer.The mechanism of prostate cancer bone metastasis is a complex process involving multiple factors and steps.In recent years,with in-depth research on the mechanism of prostate cancer bone metastasis and the development of new drugs,important progress has been made in the treatment of prostate cancer bone metastasis.Based on this,this article introduces the mechanism of prostate cancer bone metastasis and the research progress of several bone-targeted drugs to provide reference and inspiration for future research.