Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in...Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in mice and determine the underlying mechanism.Methods:First,in vitro cell proliferation and cell cycle of BMMSCs were assessed using a CCK8 assay and flow cytometry,respectively.Osteogenic differentiation was confirmed using staining and quantification of alkaline phosphatase and Alizarin Red S.Next,an osteoporotic mouse model was established by performing bilateral ovariectomy(OVX).Furthermore,the PF4 concentrations were obtained using enzymelinked immunosorbent assay.The bone microarchitecture of the femur was evaluated using microCT and histological analyses.Finally,the key regulators of osteogenesis and pathways were investigated using quantitative real-time polymerase chain reaction and Western blotting.Results:Human PF4 widely and moderately decreased the cell proliferation and osteogenic differentiation ability of BMMSCs.Furthermore,the levels of PF4 in the serum and bone marrow were generally increased,whereas bone microarchitecture deteriorated due to OVX.Moreover,in vivo mouse PF4 supplementation triggered bone deterioration of the femur.In addition,several key regulators of osteogenesis were downregulated,and the integrinα5-focal adhesion kinase-extracellular signalregulated kinase(ITGA5-FAK-ERK)pathway was inhibited due to PF4 supplementation.Conclusions:PF4 may be attributed to OVX-i nduced bone loss triggered by the suppression of bone formation in vivo and alleviate BMMSC osteogenic differentiation by inhibiting the ITGA5-FAK-ERK pathway.展开更多
Background:Escherichia coli(E.coli)infection in humans and animals usually comes with gut dysbiosis,which is potential culprit to skeletal health,it is still unclear to whether diet interfered gut microbiome changes c...Background:Escherichia coli(E.coli)infection in humans and animals usually comes with gut dysbiosis,which is potential culprit to skeletal health,it is still unclear to whether diet interfered gut microbiome changes can be a protective strategy to bone loss development.Here,the effects of resistant starch from raw potato starch(RPS),a type of prebiotic,on E.coli-induced bone loss and gut microbial composition in meat ducks were evaluated.Results:The results showed that dietary 12%RPS treatment improved bone quality,depressed bone resorption,and attenuated the pro-inflammatory reaction in both ileum and bone marrow.Meanwhile,the 12%RPS diet also increased the abundance of Firmicutes in E.coli-treated birds,along with higher production of short-chain fatty acids(SCFAs)especially propionate and butyrate.Whereas addition ofβ-acid,an inhibitor of bacterial SCFAs production,to the drinking water of ducks fed 12%RPS diet significantly decreased SCFAs level in cecum content and eliminated RPS-induced tibial mass improvement.Further,treatment with MI-2 to abrogate mucosa-associated lymphoid tissue lymphoma translocation protein 1(Malt1)activity replicated the protective role of dietary 12%RPS in E.coli-induced bone loss including reduced the inhibition on nuclear factorκB(NF-κB)inflammasome activation,decreased bone resorption,and improved bone quality,which were correlated with comparable and higher regulatory T cells(Treg)frequency in MI-2 and 12%RPS group,respectively.Conclusions:These findings suggested that the diet with 12%RPS could alleviate E.coli-induced bone loss in meat ducks by changing the gut microbial composition and promoting concomitant SCFAs production,and consequently inhibiting Malt1/NF-κB inflammasome activation and Treg cells expansion.展开更多
BACKGROUND Pyogenic granuloma(PG)is a localized,reddish and vascularized hyperplastic lesion of the connective tissue which occurs in the oral cavity.In most cases,the presence of this lesion does not show alveolar bo...BACKGROUND Pyogenic granuloma(PG)is a localized,reddish and vascularized hyperplastic lesion of the connective tissue which occurs in the oral cavity.In most cases,the presence of this lesion does not show alveolar bone resorption.The pathology is diagnosed clinically with some caution.However,the diagnosis and treatment are usually corroborated with histopathological evidence.CASE SUMMARY Three clinical cases of PG associated with bone loss were described in this study.The three patients presented tumor-like growth which bled on touch,and were associated with local irritant factors.Radiographs showed bone loss.All cases were treated with conservative surgical excision.The scarring was satisfactory,and there was no case of recurrence.The diagnoses were based on clinical findings,and were confirmed histopathologically.CONCLUSION The occurrence of oral PG with bone loss is unusual.Therefore,clinical and radiographic evaluations are important for the diagnosis.展开更多
[Objectives]To investigate the preventive effects of Wumen Gumi Bao Decoction(WMGBD)on estrogen deficiency-induced bone loss.[Methods]Three-month-old Sprague-Dawley rats were ovariectomized(OVX)and then treated with W...[Objectives]To investigate the preventive effects of Wumen Gumi Bao Decoction(WMGBD)on estrogen deficiency-induced bone loss.[Methods]Three-month-old Sprague-Dawley rats were ovariectomized(OVX)and then treated with WMGBD,and their admixtures for six weeks.The bone trabecular microstructure,bone histopathological examination were determined in the rat femur tissue,and serum biomarkers of bone formation and resorption were analyzed by ELISA,and the protein expressions of Wnt3a,β-catenin,and phosphorylatedβ-catenin(p-β-catenin)were analyzed by Western blot.Statistical analysis was conducted by using one-way analysis of variance(ANOVA)followed by LSD post hoc analysis or independent samples t test using the scientific statistic software SPSS version 20.0.[Results]WMGBD could promote osteosis and ameliorate bone loss to improve the repair of cracked bone trabeculae of OVX rats.Furthermore,WMGBD also could prevent OVX-induced decrease in collagen fibers in the femoral tissue of ovariectomized rats and promote the regeneration of new bone or cartilage tissue,while WMGBD could activate the Wnt3a/β-catenin pathway.[Conclusions]WMGBD could ameliorate estrogen deficiency-induced bone loss via the regulation of Wnt3a/β-catenin pathway.展开更多
BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains controversial.Several studi...BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains controversial.Several studies have reported the clinical characteristics of ABL and speculated on the pathogenic mechanism based on a certain type of artificial disc,while the overall understanding of ABL is lacking.AIM To describe the prevalence,impacts,and risk factors of ABL after CDR.METHODS We searched the PubMed,Cochrane Library,and Excerpta Medica databases using the terms“bone loss”or“bone remodeling”or“bone absorption”or“osteolysis”or“implant loosening”or“implant migration”or“hypersensitivity”or“hyperreactivity”,“cervical disc replacement”or“cervical disc arthroplasty”or“total disc replacement”.Eligible manuscripts on the prevalence and impacts of ABL were reviewed by the authors.Data extraction was performed using an established extraction form.The results of the included studies were described narratively.RESULTS Six studies met the inclusion and exclusion criteria.One was a prospective study and the others were retrospective studies.A total of 440 patients with 536 segments were included.The artificial cervical discs included Bryan,Baguera-C,Discocerv,and Mobi-C.The prevalence of ABL ranged from 3.13%to 91.89%,with a combined overall prevalence of 41.84%.ABL occurred within 6 mo and stopped 12 mo after surgery.Several cases were noted to have a self-healing process.Severe ABL resulted in segmental kyphosis,implant subsidence,and persistent neck pain.ABL may be related to heterotopic ossification.Multilevel surgery may be one of the risk factors for ABL.CONCLUSION ABL is a common condition after CDR.The underlying mechanisms of ABL may include stress concentration and injury to nutrient vessels.ABL should be considered a complication after CDR as it was associated with neck pain,implant subsidence,and heterotopic ossification.展开更多
Introduction Mechanotransduction has demonstrated potentials for tissue adaptation in vivo and in vitro. It is well documented that ultrasound,as a mechanical signal,can produce a wide variety of biological effects in...Introduction Mechanotransduction has demonstrated potentials for tissue adaptation in vivo and in vitro. It is well documented that ultrasound,as a mechanical signal,can produce a wide variety of biological effects in vitro and in vivo [1]. As an example,展开更多
BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed t...BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed that the effect of arthroscopic Bankart repair is unreliable.AIM To evaluate the clinical efficacy of arthroscopy with subscapularis upper one-third tenodesis for treatment of anterior shoulder instability,and to develop a method to further improve anterior stability and reduce the recurrence rate.METHODS Between January 2015 and December 2018,male patients with recurrent anterior shoulder instability were selected.One hundred and twenty patients had a glenoid defect<20%and 80 patients had a glenoid defect>20%.The average age was 25 years(range,18–45 years).Patients with a glenoid defect<20%underwent arthroscopic Bankart repair with a subscapularis upper one-third tenodesis.The patients with a glenoid defect>20%underwent an arthroscopic iliac crest bone autograft with a subscapularis upper one-third tenodesis.All patients were assessed with Rowe and Constant scores.RESULTS The average shoulder forward flexion angle was 163.6°±8.3°and 171.8°±3.6°preoperatively and at the last follow-up evaluation,respectively.The average external rotation angle when abduction was 90°was 68.4°±13.6°and 88.5°±6.2°preoperatively and at the last follow-up evaluation,respectively.The mean Rowe scores preoperatively and at the last follow-up evaluation were 32.6±3.2 and 95.2±2.2,respectively(P<0.05).The mean Constant scores preoperatively and at the last follow-up evaluation were 75.4±3.5 and 95.8±3.3,respectively(P<0.05).No postoperative dislocations were recorded by the end of the follow-up period.CONCLUSION Arthroscopy with subscapularis upper one-third tenodesis was effective for treatment of recurrent anterior shoulder instability independent of the size of the glenoid bone defect,enhanced anterior stability of the shoulder,and did not affect postoperative range of motion of the affected limb.展开更多
<b><span>Background:</span></b><span> The objective of this meta-analysis was to assess whether mini-</span><span>implants </span><span>have</span><span&g...<b><span>Background:</span></b><span> The objective of this meta-analysis was to assess whether mini-</span><span>implants </span><span>have</span><span> added benefit in terms of implants success rate and average bone loss over conventional-sized implants after one year of follow-up.</span><span> </span><b><span>Methods: </span></b><span>An electronic search of randomized clinical trials was conducted in MEDLINE (via PubMed), Cochrane Central Register of Clinical Trials (CENTRAL) and Web of Science for studies including complete or partial edentulous patients requiring two or four mini-implants or conventional/</span><span> </span><span>standard-sized implants in the maxilla or mandible for implant-supported removable prostheses who completed 12 months of follow-up. </span><b><span>Results:</span></b><span> The search provided 194 unique articles which were screened for title and abstract. Screening generated 12 articles which went through full-text analysis using eligibility criteria, and 4 articles were included for meta-analysis. Meta-analysis of these studies indicated a non-significant difference in the success rate between the two interventions (OR = 1.69 [0.74, 3.85;p = 0.21]). Bone loss estimates resulted in a significant bone reduction (Mean Difference = </span><span>-</span><span>0.74 [</span><span>-</span><span>0.95, </span><span>-</span><span>0.53;p < 0.05]) in favor of two mini-implants when compared with two conventional-sized implants, but when compared four mini</span><span>- </span><span> </span><span>with two conventional-sized implants</span><span>,</span><span> the estimates were non-significant </span><span>(Mean Difference = </span><span>-</span><span>0.24 [</span><span>-</span><span>0.69, 0.20;p = 0.29]). </span><b><span>Conclusion: </span></b><span>The current evidence does not provide solid evidence of the benefits of one intervention over the other. More studies with follow-up times of 10 and more years are needed as current studies have described the short-term outcomes.</span>展开更多
<strong>Background: </strong>Type-2 diabetic patients (uncontrolled levels of glucose blood) usually have periodontal diseases and alveolar bone loss. <strong>Objectives: </strong>The present s...<strong>Background: </strong>Type-2 diabetic patients (uncontrolled levels of glucose blood) usually have periodontal diseases and alveolar bone loss. <strong>Objectives: </strong>The present study was designed to clarify the impact of severity of periodontal bone loss and the levels of glycated hemoglobin (HbA1c) on the periodontal clinical parameters of the 2017 World Workshop among type 2 diabetic patients in Saudi Arabia (Saudi and non-Saudi). <strong>Material and Methods: </strong>This study was done on 298 type 2 diabetic patients, selected from the internship clinics, College of Dentistry, King Khalid University, Abha, Saudi Arabia. The selection of patients was dependent on the levels of glycated hemoglobin (HbA1c), and they were categorized into controlled (<7% HbA1c) and uncontrolled type 2 diabetics (>7% HbA1c). All patients were divided according to the severity of periodontal bone loss into three groups, group I: mild periodontal bone loss, group II: moderate periodontal bone loss, and group III: severe periodontal bone loss. Clinical evaluation of periodontal diseases was carried out by clinical parameters according to the 2017 World Workshop. All data were collected and analyzed. A p-value of <0.05 was considered significant, and of <0.001 was considered highly significant. <strong>Results:</strong> The severity of periodontal bone loss were determined in controlled type 2 diabetics (<7% HbA1c) and compared to uncontrolled type 2 diabetics (>7% HbA1c). An increased percentage of patients with severe periodontal bone loss was observed in uncontrolled type 2 diabetics (>7% HbA1c) (42.9%), as compared to controlled type 2 diabetics (<7% HbA1c) (30.5%) without statistically significant (p = 0.251). An increased mean of age, clinical attachment loss (CAL), and percentage of radiographic bone loss (% RBL) were detected in controlled type 2 diabetics (<7% HbA1c), as compared to uncontrolled type 2 diabetics (>7% HbA1c). In contrast, we found an increased mean of plaque control record (PCR), gingival bleeding index (GBI), and periodontal pocket depth (PPD) in uncontrolled type 2 diabetics (>7% HbA1c) more than in controlled type 2 diabetics (<7% HbA1c) without statistically significant (p > 0.05). Moreover, the mean of age, PCR, CAL, % RBL, and PPD were more in the patients with severe periodontal bone loss, as compared to the patients with mild and moderate periodontal bone. Highly statistically significant differences were recorded (p < 0.001). <strong>Conclusion:</strong> This study demonstrates the role of uncontrolled diabetes as a risk factor for the increase in the severity of periodontal bone loss. Thus, we suggest including the glycated hemoglobin (HbA1c) levels with periodontal parameters in the evaluation of periodontal bone loss among type 2 diabetics.展开更多
The purpose of this study is to evaluate our results of treatment of post-traumatic bone defect of members through various bone reconstruction techniques. Patients and method: It is a retrospective study continues fro...The purpose of this study is to evaluate our results of treatment of post-traumatic bone defect of members through various bone reconstruction techniques. Patients and method: It is a retrospective study continues from January 2008 to December 2012. It involved 27 patients who had bone loss following trauma members. The average age of patients was 36.2 years. We noted a male predominance (22 men). The causes of injuries were dominated by accidents of public roads (12 cases) and ballistic trauma (14 cases). We noted one case of work accident. The BL was localized in 10 cases the tibia, femur in 4 cases, 8 cases in the humerus, 2 cases in the fibula, 1 case was located in the olecranon, 1 case at the distal radius and 1 case to the ball. All lesions were open fractures. After a mean of support for 3 days, we performed emergency around 19 associated with internal fixation (10 cases external fixation, internal fixation 9 cases), 8 single around. Bone reconstruction was performed secondarily in the majority of cases (24 cases). Only 4 reconstructions were performed in emergency. Reconstruction techniques were dominated by conventional grafts (24 cases) associated or not with the technique of induced membrane. Bone reconstruction techniques we used were as follows: 24 cases of traditional autografts and 3 cases of intertibio-fibular graft. After an average decline of 43.6 months, our patients were evaluated clinically (axis and limb length) and radiological (bone healing). Results: bone healing was achieved in 22 cases after a mean of 3.8 surgeries and an average of 14.8 months. Conclusion: the main principles governing the reconstruction of a defect are pre healing associated infection and repair soft tissue whenever it can do. The current trend is to hybridization of the reconstruction process of the great losses of substance by developing strategies based on both the deliberate shortening.展开更多
Hypoxia(low oxygen level) is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation o...Hypoxia(low oxygen level) is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1(HIF-1).Hypoxia interferes degradation of HIF-1 alpha subunit(HIF-1α), leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit(HIF-1β) and subsequent activation of HIF-1 pathway. Apical periodontitis(periapical lesion) is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine(DMOG) and adenovirusinduced constitutively active HIF-1α(CA-HIF1 A). Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B(NF-κB) and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.展开更多
Objective To better understand the pathological causes of bone loss in a space environment, including microgravity, ionizing radiation, and ultradian rhythms. Methods Sprague Dawley(SD) rats were randomly divided into...Objective To better understand the pathological causes of bone loss in a space environment, including microgravity, ionizing radiation, and ultradian rhythms. Methods Sprague Dawley(SD) rats were randomly divided into a baseline group, a control group, a hindlimb suspension group, a radiation group, a ultradian rhythms group and a combined-three-factor group. After four weeks of hindlimb suspension followed by X-ray exposure and/or ultradian rhythms, biomechanical properties, bone mineral density, histological analysis, microstructure parameters, and bone turnover markers were detected to evaluate bone loss in hindlimbs of rats. Results Simulated microgravity or combined-three factors treatment led to a significant decrease in the biomechanical properties of bones, reduction in bone mineral density, and deterioration of trabecular parameters. Ionizing radiation exposure also showed adverse impact while ultradian rhythms had no significant effect on these outcomes. Decrease in the concentration of the turnover markers bone alkaline phosphatase(b ALP), osteocalcin(OCN), and tartrate-resistant acid phosphatase-5 b(TRAP-5 b) in serum was in line with the changes in trabecular parameters. Conclusion Simulated microgravity is the main contributor of bone loss. Radiation also results in deleterious effects but ultradian rhythms has no significant effect. Combined-three factors treatment do not exacerbate bone loss when compared to simulated microgravity treatment alone.展开更多
The management of recurrent anterior gleno-humeral joint instability is challenging in the presence of boneloss.It is often seen in young athletic patients and dislocations related to epileptic seizures and may involv...The management of recurrent anterior gleno-humeral joint instability is challenging in the presence of boneloss.It is often seen in young athletic patients and dislocations related to epileptic seizures and may involve glenoid bone deficiency,humeral bone deficiency or combined bipolar lesions.It is critical to accurately identify and assess the amount and position of bone loss in order to select the most appropriate treatment and reduce the risk of recurrent instability after surgery.The current literature suggests that coracoid and iliac crest bone block transfers are reliable for treating glenoid defects.The treatment of humeral defects is more controversial,however,although good early results have been reported after arthroscopic Remplissage for small defects.Larger humeral defects may require complex reconstruction or partial resurfacing.There is currently very limited evidence to support treatment strategies when dealing with bipolar lesions.The aim of this review is to summarise the current evidence regarding the best imaging modalities and treatment strategies in managing this complex problem relating particularly to contact athletes and dislocations related to epileptic seizures.展开更多
The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to in...The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approachfor reconstruction of different types of proximal femoral bone defects.展开更多
Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors.Regulation of osteoclast differentiation is considered an effective therapeutic approach to...Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors.Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases.Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride(Na F) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. Na F strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin(IL)-1β, matrix metalloproteinase 9(MMP9), and tartrate-resistant acid phosphatase,which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect,Na F inhibited osteoclast formation caused by the differentiation factor RANKL(receptor activator of nuclear factor kB ligand)and macrophage colony-stimulating factor(M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells(NFAT) c1 was also abrogated by Na F. Taken together, our data demonstrate that Na F inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9.The in vivo effect of Na F on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of Na F for treating periodontal diseases.展开更多
Marginal bone loss during bone healing exists around non-submerged dental implants. The aim of this study was to identify the relationship between different degrees of marginal bone loss during bone healing and the sa...Marginal bone loss during bone healing exists around non-submerged dental implants. The aim of this study was to identify the relationship between different degrees of marginal bone loss during bone healing and the salivary microbiome. One hundred patients were recruited, and marginal bone loss around their implants was measured using cone beam computed tomography during a 3-month healing period. The patients were divided into three groups according to the severity of marginal bone loss.Saliva samples were collected from all subjected and were analysed using 16 SMiSeq sequencing. Although the overall structure of the microbial community was not dramatically altered, the relative abundance of several taxonomic groups noticeably changed. The abundance of species in the phyla Spirochaeta and Synergistetes increased significantly as the bone loss became more severe. Species within the genus Treponema also exhibited increased abundance, whereas Veillonella, Haemophilus and Leptotrichia exhibited reduced abundances, in groups with more bone loss. Porphyromonasgingivalis, Treponemadenticola and Streptococcus intermedius were significantly more abundant in the moderate group and/or severe group. The severity of marginal bone loss around the non-submerged implant was associated with dissimilar taxonomic compositions. An increased severity of marginal bone loss was related to increased proportions of periodontal pathogenic species. These data suggest a potential role of microbes in the progression of marginal bone loss during bone healing.展开更多
Dysregulated Wnt signaling is associated with the pathogenesis of cancers, fibrosis, and vascular diseases. Inhibition of Wnt signaling has shown efficacy in various pre-clinical models of these disorders. One of the ...Dysregulated Wnt signaling is associated with the pathogenesis of cancers, fibrosis, and vascular diseases. Inhibition of Wnt signaling has shown efficacy in various pre-clinical models of these disorders. One of the key challenges in developing targeted anti-cancer drugs is to balance efficacy with on-target toxicity. Given the crucial role Wnts play in the differentiation of osteoblasts and osteoclasts, acute inhibition of Wnt signaling is likely to affect bone homeostasis. In this study, we evaluated the skeletal effect of small molecule inhibitor of an o-acyl transferase porcupine(PORCN) that prevents Wnt signaling by blocking the secretion of all Wnts. Micro-computed tomography and histomorphometric evaluation revealed that the bones of mice treated with two structurally distinct PORCN inhibitors LGK974 and ETC-1922159(ETC-159) had loss-of-bone volume and density within 4 weeks of exposure. This decreased bone mass was associated with a significant increase in adipocytes within the bone marrow. Notably,simultaneous administration of a clinically approved anti-resorptive, alendronate, a member of the bisphosphonate family,mitigated loss-of-bone mass seen upon ETC-159 treatment by regulating activity of osteoclasts and blocking accumulation of bone marrow adipocytes. Our results support the addition of bone protective agents when treating patients with PORCN inhibitors.Mitigation of bone toxicity can extend the therapeutic utility of Wnt pathway inhibitors.展开更多
Background: Periodontal disease is a bacterial infection that causes bone resorption of bone supporting teeth and leads to change in the normal architecture of the alveolar process. There are instances where the techn...Background: Periodontal disease is a bacterial infection that causes bone resorption of bone supporting teeth and leads to change in the normal architecture of the alveolar process. There are instances where the technique sensitive nature of restorative procedures or the faulty restorative margins may inadvertently lead to conditions which could bring about periodontal disease/ destruction. Therefore, this study was designed to determine the impact of dental restorations type on marginal bone among some patients being treated for chronic periodontitis. Material and Methods: Three hundred patients from the periodontics clinics in college of dentistry, King Khalid university were participated in our study. A total of 292 patients completed the study, 152 males and 140 female. They were divided according to dental reconstructions into three groups: Group I was without dental reconstructions (control group), group II patients received amalgam class II fillings and group III received fixed bridge denture. Plaque index (PLI) gingival index (GI), clinical attachment loss (CAL) and marginal bone loss (MBL) were recorded. All data were collected and were analyzed by ANOVA test. Results: In the present study, the restored teeth revealed significantly higher mean values for PLI, GI, CAL and MBL than the non-restored teeth (p-value Conclusion: Although the limitations of the present study, the patients in group II had the highest clinical attachment loss and value of marginal bone loss which can explain the more extension of amalgam fillings into subgingival direction, leading to increased plaque accumulation and increased periodontal destruction.展开更多
The effect of age-related bone loss on the structural capacity of the proximal femur were investigated by Finite Element Analysis (FEA). Four bone loss patterns were considered. These were "uniform cortical bone ...The effect of age-related bone loss on the structural capacity of the proximal femur were investigated by Finite Element Analysis (FEA). Four bone loss patterns were considered. These were "uniform cortical bone loss", "neck cortical bone loss", "intertrochanteric cortical bone loss" and "uniform trabecular bone loss". The results show that the two "non-uniform cortical bone loss" patterns are more dangerous than the "uniform cortical bone loss" pattern, and that the cortical bone loss in intertrochanteric region is associated with a greater reduction in cortical failure load than the cortical bone loss in the femoral neck. The trabecular bone loss causes a limited decrease in both cortical failure and trabecular failure loads. This research should be helpful to the clinical assessment of femur fracture risk due to age-related bone loss.展开更多
基金Beijing Natural Science Foundation,Grant/Award Number:L222145CAMS Innovation Fund for Medical Sciences,Grant/Award Number:2019-I2M-5-038+2 种基金Clinical Medicine Plus X-Young Scholars Project,Peking Universitythe Fundamental Research Funds for the Central Universities,Grant/Award Number:PKU2023LCXQ017National Natural Science Foundation of China,Grant/Award Number:81700935。
文摘Background:The effect of platelet factor 4(PF4)on bone marrow mesenchymal stem cells(BMMSCs)and osteoporosis is poorly understood.Therefore,this study aimed to evaluate the effects of PF4-triggered bone destruction in mice and determine the underlying mechanism.Methods:First,in vitro cell proliferation and cell cycle of BMMSCs were assessed using a CCK8 assay and flow cytometry,respectively.Osteogenic differentiation was confirmed using staining and quantification of alkaline phosphatase and Alizarin Red S.Next,an osteoporotic mouse model was established by performing bilateral ovariectomy(OVX).Furthermore,the PF4 concentrations were obtained using enzymelinked immunosorbent assay.The bone microarchitecture of the femur was evaluated using microCT and histological analyses.Finally,the key regulators of osteogenesis and pathways were investigated using quantitative real-time polymerase chain reaction and Western blotting.Results:Human PF4 widely and moderately decreased the cell proliferation and osteogenic differentiation ability of BMMSCs.Furthermore,the levels of PF4 in the serum and bone marrow were generally increased,whereas bone microarchitecture deteriorated due to OVX.Moreover,in vivo mouse PF4 supplementation triggered bone deterioration of the femur.In addition,several key regulators of osteogenesis were downregulated,and the integrinα5-focal adhesion kinase-extracellular signalregulated kinase(ITGA5-FAK-ERK)pathway was inhibited due to PF4 supplementation.Conclusions:PF4 may be attributed to OVX-i nduced bone loss triggered by the suppression of bone formation in vivo and alleviate BMMSC osteogenic differentiation by inhibiting the ITGA5-FAK-ERK pathway.
基金the National Natural Science Foundation of China(No.31772622)National Natural Science Foundation of China(No.32072748)Doctoral Fellowship from Henan Agricultural University(No.0501182)。
文摘Background:Escherichia coli(E.coli)infection in humans and animals usually comes with gut dysbiosis,which is potential culprit to skeletal health,it is still unclear to whether diet interfered gut microbiome changes can be a protective strategy to bone loss development.Here,the effects of resistant starch from raw potato starch(RPS),a type of prebiotic,on E.coli-induced bone loss and gut microbial composition in meat ducks were evaluated.Results:The results showed that dietary 12%RPS treatment improved bone quality,depressed bone resorption,and attenuated the pro-inflammatory reaction in both ileum and bone marrow.Meanwhile,the 12%RPS diet also increased the abundance of Firmicutes in E.coli-treated birds,along with higher production of short-chain fatty acids(SCFAs)especially propionate and butyrate.Whereas addition ofβ-acid,an inhibitor of bacterial SCFAs production,to the drinking water of ducks fed 12%RPS diet significantly decreased SCFAs level in cecum content and eliminated RPS-induced tibial mass improvement.Further,treatment with MI-2 to abrogate mucosa-associated lymphoid tissue lymphoma translocation protein 1(Malt1)activity replicated the protective role of dietary 12%RPS in E.coli-induced bone loss including reduced the inhibition on nuclear factorκB(NF-κB)inflammasome activation,decreased bone resorption,and improved bone quality,which were correlated with comparable and higher regulatory T cells(Treg)frequency in MI-2 and 12%RPS group,respectively.Conclusions:These findings suggested that the diet with 12%RPS could alleviate E.coli-induced bone loss in meat ducks by changing the gut microbial composition and promoting concomitant SCFAs production,and consequently inhibiting Malt1/NF-κB inflammasome activation and Treg cells expansion.
文摘BACKGROUND Pyogenic granuloma(PG)is a localized,reddish and vascularized hyperplastic lesion of the connective tissue which occurs in the oral cavity.In most cases,the presence of this lesion does not show alveolar bone resorption.The pathology is diagnosed clinically with some caution.However,the diagnosis and treatment are usually corroborated with histopathological evidence.CASE SUMMARY Three clinical cases of PG associated with bone loss were described in this study.The three patients presented tumor-like growth which bled on touch,and were associated with local irritant factors.Radiographs showed bone loss.All cases were treated with conservative surgical excision.The scarring was satisfactory,and there was no case of recurrence.The diagnoses were based on clinical findings,and were confirmed histopathologically.CONCLUSION The occurrence of oral PG with bone loss is unusual.Therefore,clinical and radiographic evaluations are important for the diagnosis.
基金Supported by Senile Health Research Project of Jiangsu Provincial Health Commission of China(LKZ2023217)Natural Science Foundation of Nanjing University of Traditional Chinese Medicine(XAR2021041)+1 种基金Suzhou Science and Technology Development Plan Project(SYSD2020215,SKY2022202)The Ninth Batch of Suzhou Gusu Health Key Talents Project(GSWS2022107)。
文摘[Objectives]To investigate the preventive effects of Wumen Gumi Bao Decoction(WMGBD)on estrogen deficiency-induced bone loss.[Methods]Three-month-old Sprague-Dawley rats were ovariectomized(OVX)and then treated with WMGBD,and their admixtures for six weeks.The bone trabecular microstructure,bone histopathological examination were determined in the rat femur tissue,and serum biomarkers of bone formation and resorption were analyzed by ELISA,and the protein expressions of Wnt3a,β-catenin,and phosphorylatedβ-catenin(p-β-catenin)were analyzed by Western blot.Statistical analysis was conducted by using one-way analysis of variance(ANOVA)followed by LSD post hoc analysis or independent samples t test using the scientific statistic software SPSS version 20.0.[Results]WMGBD could promote osteosis and ameliorate bone loss to improve the repair of cracked bone trabeculae of OVX rats.Furthermore,WMGBD also could prevent OVX-induced decrease in collagen fibers in the femoral tissue of ovariectomized rats and promote the regeneration of new bone or cartilage tissue,while WMGBD could activate the Wnt3a/β-catenin pathway.[Conclusions]WMGBD could ameliorate estrogen deficiency-induced bone loss via the regulation of Wnt3a/β-catenin pathway.
基金Supported by West China Nursing Discipline Development Special Fund Project,Sichuan University,No.HXHL190161.3.5 Project for Disciplines of Excellence,West China Hospital,Sichuan University,No.ZYJC18029.
文摘BACKGROUND Anterior bone loss(ABL)is a relatively easily neglected condition after cervical disc replacement(CDR).Whether this phenomenon is a radiological anomaly or a complication remains controversial.Several studies have reported the clinical characteristics of ABL and speculated on the pathogenic mechanism based on a certain type of artificial disc,while the overall understanding of ABL is lacking.AIM To describe the prevalence,impacts,and risk factors of ABL after CDR.METHODS We searched the PubMed,Cochrane Library,and Excerpta Medica databases using the terms“bone loss”or“bone remodeling”or“bone absorption”or“osteolysis”or“implant loosening”or“implant migration”or“hypersensitivity”or“hyperreactivity”,“cervical disc replacement”or“cervical disc arthroplasty”or“total disc replacement”.Eligible manuscripts on the prevalence and impacts of ABL were reviewed by the authors.Data extraction was performed using an established extraction form.The results of the included studies were described narratively.RESULTS Six studies met the inclusion and exclusion criteria.One was a prospective study and the others were retrospective studies.A total of 440 patients with 536 segments were included.The artificial cervical discs included Bryan,Baguera-C,Discocerv,and Mobi-C.The prevalence of ABL ranged from 3.13%to 91.89%,with a combined overall prevalence of 41.84%.ABL occurred within 6 mo and stopped 12 mo after surgery.Several cases were noted to have a self-healing process.Severe ABL resulted in segmental kyphosis,implant subsidence,and persistent neck pain.ABL may be related to heterotopic ossification.Multilevel surgery may be one of the risk factors for ABL.CONCLUSION ABL is a common condition after CDR.The underlying mechanisms of ABL may include stress concentration and injury to nutrient vessels.ABL should be considered a complication after CDR as it was associated with neck pain,implant subsidence,and heterotopic ossification.
基金supported by the NIH (R01 AR52379 & R01 AR49286),U S Army Medical Research and NSBRI
文摘Introduction Mechanotransduction has demonstrated potentials for tissue adaptation in vivo and in vitro. It is well documented that ultrasound,as a mechanical signal,can produce a wide variety of biological effects in vitro and in vivo [1]. As an example,
文摘BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed that the effect of arthroscopic Bankart repair is unreliable.AIM To evaluate the clinical efficacy of arthroscopy with subscapularis upper one-third tenodesis for treatment of anterior shoulder instability,and to develop a method to further improve anterior stability and reduce the recurrence rate.METHODS Between January 2015 and December 2018,male patients with recurrent anterior shoulder instability were selected.One hundred and twenty patients had a glenoid defect<20%and 80 patients had a glenoid defect>20%.The average age was 25 years(range,18–45 years).Patients with a glenoid defect<20%underwent arthroscopic Bankart repair with a subscapularis upper one-third tenodesis.The patients with a glenoid defect>20%underwent an arthroscopic iliac crest bone autograft with a subscapularis upper one-third tenodesis.All patients were assessed with Rowe and Constant scores.RESULTS The average shoulder forward flexion angle was 163.6°±8.3°and 171.8°±3.6°preoperatively and at the last follow-up evaluation,respectively.The average external rotation angle when abduction was 90°was 68.4°±13.6°and 88.5°±6.2°preoperatively and at the last follow-up evaluation,respectively.The mean Rowe scores preoperatively and at the last follow-up evaluation were 32.6±3.2 and 95.2±2.2,respectively(P<0.05).The mean Constant scores preoperatively and at the last follow-up evaluation were 75.4±3.5 and 95.8±3.3,respectively(P<0.05).No postoperative dislocations were recorded by the end of the follow-up period.CONCLUSION Arthroscopy with subscapularis upper one-third tenodesis was effective for treatment of recurrent anterior shoulder instability independent of the size of the glenoid bone defect,enhanced anterior stability of the shoulder,and did not affect postoperative range of motion of the affected limb.
文摘<b><span>Background:</span></b><span> The objective of this meta-analysis was to assess whether mini-</span><span>implants </span><span>have</span><span> added benefit in terms of implants success rate and average bone loss over conventional-sized implants after one year of follow-up.</span><span> </span><b><span>Methods: </span></b><span>An electronic search of randomized clinical trials was conducted in MEDLINE (via PubMed), Cochrane Central Register of Clinical Trials (CENTRAL) and Web of Science for studies including complete or partial edentulous patients requiring two or four mini-implants or conventional/</span><span> </span><span>standard-sized implants in the maxilla or mandible for implant-supported removable prostheses who completed 12 months of follow-up. </span><b><span>Results:</span></b><span> The search provided 194 unique articles which were screened for title and abstract. Screening generated 12 articles which went through full-text analysis using eligibility criteria, and 4 articles were included for meta-analysis. Meta-analysis of these studies indicated a non-significant difference in the success rate between the two interventions (OR = 1.69 [0.74, 3.85;p = 0.21]). Bone loss estimates resulted in a significant bone reduction (Mean Difference = </span><span>-</span><span>0.74 [</span><span>-</span><span>0.95, </span><span>-</span><span>0.53;p < 0.05]) in favor of two mini-implants when compared with two conventional-sized implants, but when compared four mini</span><span>- </span><span> </span><span>with two conventional-sized implants</span><span>,</span><span> the estimates were non-significant </span><span>(Mean Difference = </span><span>-</span><span>0.24 [</span><span>-</span><span>0.69, 0.20;p = 0.29]). </span><b><span>Conclusion: </span></b><span>The current evidence does not provide solid evidence of the benefits of one intervention over the other. More studies with follow-up times of 10 and more years are needed as current studies have described the short-term outcomes.</span>
文摘<strong>Background: </strong>Type-2 diabetic patients (uncontrolled levels of glucose blood) usually have periodontal diseases and alveolar bone loss. <strong>Objectives: </strong>The present study was designed to clarify the impact of severity of periodontal bone loss and the levels of glycated hemoglobin (HbA1c) on the periodontal clinical parameters of the 2017 World Workshop among type 2 diabetic patients in Saudi Arabia (Saudi and non-Saudi). <strong>Material and Methods: </strong>This study was done on 298 type 2 diabetic patients, selected from the internship clinics, College of Dentistry, King Khalid University, Abha, Saudi Arabia. The selection of patients was dependent on the levels of glycated hemoglobin (HbA1c), and they were categorized into controlled (<7% HbA1c) and uncontrolled type 2 diabetics (>7% HbA1c). All patients were divided according to the severity of periodontal bone loss into three groups, group I: mild periodontal bone loss, group II: moderate periodontal bone loss, and group III: severe periodontal bone loss. Clinical evaluation of periodontal diseases was carried out by clinical parameters according to the 2017 World Workshop. All data were collected and analyzed. A p-value of <0.05 was considered significant, and of <0.001 was considered highly significant. <strong>Results:</strong> The severity of periodontal bone loss were determined in controlled type 2 diabetics (<7% HbA1c) and compared to uncontrolled type 2 diabetics (>7% HbA1c). An increased percentage of patients with severe periodontal bone loss was observed in uncontrolled type 2 diabetics (>7% HbA1c) (42.9%), as compared to controlled type 2 diabetics (<7% HbA1c) (30.5%) without statistically significant (p = 0.251). An increased mean of age, clinical attachment loss (CAL), and percentage of radiographic bone loss (% RBL) were detected in controlled type 2 diabetics (<7% HbA1c), as compared to uncontrolled type 2 diabetics (>7% HbA1c). In contrast, we found an increased mean of plaque control record (PCR), gingival bleeding index (GBI), and periodontal pocket depth (PPD) in uncontrolled type 2 diabetics (>7% HbA1c) more than in controlled type 2 diabetics (<7% HbA1c) without statistically significant (p > 0.05). Moreover, the mean of age, PCR, CAL, % RBL, and PPD were more in the patients with severe periodontal bone loss, as compared to the patients with mild and moderate periodontal bone. Highly statistically significant differences were recorded (p < 0.001). <strong>Conclusion:</strong> This study demonstrates the role of uncontrolled diabetes as a risk factor for the increase in the severity of periodontal bone loss. Thus, we suggest including the glycated hemoglobin (HbA1c) levels with periodontal parameters in the evaluation of periodontal bone loss among type 2 diabetics.
文摘The purpose of this study is to evaluate our results of treatment of post-traumatic bone defect of members through various bone reconstruction techniques. Patients and method: It is a retrospective study continues from January 2008 to December 2012. It involved 27 patients who had bone loss following trauma members. The average age of patients was 36.2 years. We noted a male predominance (22 men). The causes of injuries were dominated by accidents of public roads (12 cases) and ballistic trauma (14 cases). We noted one case of work accident. The BL was localized in 10 cases the tibia, femur in 4 cases, 8 cases in the humerus, 2 cases in the fibula, 1 case was located in the olecranon, 1 case at the distal radius and 1 case to the ball. All lesions were open fractures. After a mean of support for 3 days, we performed emergency around 19 associated with internal fixation (10 cases external fixation, internal fixation 9 cases), 8 single around. Bone reconstruction was performed secondarily in the majority of cases (24 cases). Only 4 reconstructions were performed in emergency. Reconstruction techniques were dominated by conventional grafts (24 cases) associated or not with the technique of induced membrane. Bone reconstruction techniques we used were as follows: 24 cases of traditional autografts and 3 cases of intertibio-fibular graft. After an average decline of 43.6 months, our patients were evaluated clinically (axis and limb length) and radiological (bone healing). Results: bone healing was achieved in 22 cases after a mean of 3.8 surgeries and an average of 14.8 months. Conclusion: the main principles governing the reconstruction of a defect are pre healing associated infection and repair soft tissue whenever it can do. The current trend is to hybridization of the reconstruction process of the great losses of substance by developing strategies based on both the deliberate shortening.
基金supported by the National Institute of Dental and Craniofacial Research(NIDCR)the National Center for Research Resources(NCRR)of the National Institutes of Health(NIH)under award numbers R21DE023178,R01DE024796,and S10RR027553
文摘Hypoxia(low oxygen level) is an important feature during infections and affects the host defence mechanisms. The host has evolved specific responses to address hypoxia, which are strongly dependent on the activation of hypoxia-inducible factor 1(HIF-1).Hypoxia interferes degradation of HIF-1 alpha subunit(HIF-1α), leading to stabilisation of HIF-1α, heterodimerization with HIF-1 beta subunit(HIF-1β) and subsequent activation of HIF-1 pathway. Apical periodontitis(periapical lesion) is a consequence of endodontic infection and ultimately results in destruction of tooth-supporting tissue, including alveolar bone. Thus far, the role of HIF-1 in periapical lesions has not been systematically examined. In the present study, we determined the role of HIF-1 in a wellcharacterised mouse periapical lesion model using two HIF-1α-activating strategies, dimethyloxalylglycine(DMOG) and adenovirusinduced constitutively active HIF-1α(CA-HIF1 A). Both DMOG and CA-HIF1 A attenuated periapical inflammation and tissue destruction. The attenuation in vivo was associated with downregulation of nuclear factor-κappa B(NF-κB) and osteoclastic gene expressions. These two agents also suppressed NF-κB activation and subsequent production of proinflammatory cytokines by macrophages. Furthermore, activation of HIF-1α by DMOG specifically suppressed lipopolysaccharide-stimulated macrophage differentiation into M1 cells, increasing the ratio of M2 macrophages against M1 cells. Taken together, our data indicated that activation of HIF-1 plays a protective role in the development of apical periodontitis via downregulation of NF-κB, proinflammatory cytokines, M1 macrophages and osteoclastogenesis.
基金supported by the International Science&Technology Cooperation Program of China[No.2015DFR30940]the Science and Technology Research Project of Gansu Province[No.145RTSA012 and No.17JR5RA307]
文摘Objective To better understand the pathological causes of bone loss in a space environment, including microgravity, ionizing radiation, and ultradian rhythms. Methods Sprague Dawley(SD) rats were randomly divided into a baseline group, a control group, a hindlimb suspension group, a radiation group, a ultradian rhythms group and a combined-three-factor group. After four weeks of hindlimb suspension followed by X-ray exposure and/or ultradian rhythms, biomechanical properties, bone mineral density, histological analysis, microstructure parameters, and bone turnover markers were detected to evaluate bone loss in hindlimbs of rats. Results Simulated microgravity or combined-three factors treatment led to a significant decrease in the biomechanical properties of bones, reduction in bone mineral density, and deterioration of trabecular parameters. Ionizing radiation exposure also showed adverse impact while ultradian rhythms had no significant effect on these outcomes. Decrease in the concentration of the turnover markers bone alkaline phosphatase(b ALP), osteocalcin(OCN), and tartrate-resistant acid phosphatase-5 b(TRAP-5 b) in serum was in line with the changes in trabecular parameters. Conclusion Simulated microgravity is the main contributor of bone loss. Radiation also results in deleterious effects but ultradian rhythms has no significant effect. Combined-three factors treatment do not exacerbate bone loss when compared to simulated microgravity treatment alone.
文摘The management of recurrent anterior gleno-humeral joint instability is challenging in the presence of boneloss.It is often seen in young athletic patients and dislocations related to epileptic seizures and may involve glenoid bone deficiency,humeral bone deficiency or combined bipolar lesions.It is critical to accurately identify and assess the amount and position of bone loss in order to select the most appropriate treatment and reduce the risk of recurrent instability after surgery.The current literature suggests that coracoid and iliac crest bone block transfers are reliable for treating glenoid defects.The treatment of humeral defects is more controversial,however,although good early results have been reported after arthroscopic Remplissage for small defects.Larger humeral defects may require complex reconstruction or partial resurfacing.There is currently very limited evidence to support treatment strategies when dealing with bipolar lesions.The aim of this review is to summarise the current evidence regarding the best imaging modalities and treatment strategies in managing this complex problem relating particularly to contact athletes and dislocations related to epileptic seizures.
文摘The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approachfor reconstruction of different types of proximal femoral bone defects.
文摘Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors.Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases.Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride(Na F) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. Na F strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin(IL)-1β, matrix metalloproteinase 9(MMP9), and tartrate-resistant acid phosphatase,which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect,Na F inhibited osteoclast formation caused by the differentiation factor RANKL(receptor activator of nuclear factor kB ligand)and macrophage colony-stimulating factor(M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells(NFAT) c1 was also abrogated by Na F. Taken together, our data demonstrate that Na F inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9.The in vivo effect of Na F on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of Na F for treating periodontal diseases.
基金supported by grants from the National Natural Science Foundation of China(NSFC8137117381571001)+2 种基金State Key Laboratory of Oral Diseases(SKLOD201704)International Team for Implantology(Grant No.975_2014,Basel,Switzerland)to Quan Yuanthe National Key R&D Program of China during the 13th Five-Year Plan(2016YFC1102700)to Xue-Dong Zhou
文摘Marginal bone loss during bone healing exists around non-submerged dental implants. The aim of this study was to identify the relationship between different degrees of marginal bone loss during bone healing and the salivary microbiome. One hundred patients were recruited, and marginal bone loss around their implants was measured using cone beam computed tomography during a 3-month healing period. The patients were divided into three groups according to the severity of marginal bone loss.Saliva samples were collected from all subjected and were analysed using 16 SMiSeq sequencing. Although the overall structure of the microbial community was not dramatically altered, the relative abundance of several taxonomic groups noticeably changed. The abundance of species in the phyla Spirochaeta and Synergistetes increased significantly as the bone loss became more severe. Species within the genus Treponema also exhibited increased abundance, whereas Veillonella, Haemophilus and Leptotrichia exhibited reduced abundances, in groups with more bone loss. Porphyromonasgingivalis, Treponemadenticola and Streptococcus intermedius were significantly more abundant in the moderate group and/or severe group. The severity of marginal bone loss around the non-submerged implant was associated with dissimilar taxonomic compositions. An increased severity of marginal bone loss was related to increased proportions of periodontal pathogenic species. These data suggest a potential role of microbes in the progression of marginal bone loss during bone healing.
基金supported by an NIH grant to BOW (R01AR053293)the Van Andel Research Institutesupported in part by the National Research Foundation Singapore
文摘Dysregulated Wnt signaling is associated with the pathogenesis of cancers, fibrosis, and vascular diseases. Inhibition of Wnt signaling has shown efficacy in various pre-clinical models of these disorders. One of the key challenges in developing targeted anti-cancer drugs is to balance efficacy with on-target toxicity. Given the crucial role Wnts play in the differentiation of osteoblasts and osteoclasts, acute inhibition of Wnt signaling is likely to affect bone homeostasis. In this study, we evaluated the skeletal effect of small molecule inhibitor of an o-acyl transferase porcupine(PORCN) that prevents Wnt signaling by blocking the secretion of all Wnts. Micro-computed tomography and histomorphometric evaluation revealed that the bones of mice treated with two structurally distinct PORCN inhibitors LGK974 and ETC-1922159(ETC-159) had loss-of-bone volume and density within 4 weeks of exposure. This decreased bone mass was associated with a significant increase in adipocytes within the bone marrow. Notably,simultaneous administration of a clinically approved anti-resorptive, alendronate, a member of the bisphosphonate family,mitigated loss-of-bone mass seen upon ETC-159 treatment by regulating activity of osteoclasts and blocking accumulation of bone marrow adipocytes. Our results support the addition of bone protective agents when treating patients with PORCN inhibitors.Mitigation of bone toxicity can extend the therapeutic utility of Wnt pathway inhibitors.
文摘Background: Periodontal disease is a bacterial infection that causes bone resorption of bone supporting teeth and leads to change in the normal architecture of the alveolar process. There are instances where the technique sensitive nature of restorative procedures or the faulty restorative margins may inadvertently lead to conditions which could bring about periodontal disease/ destruction. Therefore, this study was designed to determine the impact of dental restorations type on marginal bone among some patients being treated for chronic periodontitis. Material and Methods: Three hundred patients from the periodontics clinics in college of dentistry, King Khalid university were participated in our study. A total of 292 patients completed the study, 152 males and 140 female. They were divided according to dental reconstructions into three groups: Group I was without dental reconstructions (control group), group II patients received amalgam class II fillings and group III received fixed bridge denture. Plaque index (PLI) gingival index (GI), clinical attachment loss (CAL) and marginal bone loss (MBL) were recorded. All data were collected and were analyzed by ANOVA test. Results: In the present study, the restored teeth revealed significantly higher mean values for PLI, GI, CAL and MBL than the non-restored teeth (p-value Conclusion: Although the limitations of the present study, the patients in group II had the highest clinical attachment loss and value of marginal bone loss which can explain the more extension of amalgam fillings into subgingival direction, leading to increased plaque accumulation and increased periodontal destruction.
文摘The effect of age-related bone loss on the structural capacity of the proximal femur were investigated by Finite Element Analysis (FEA). Four bone loss patterns were considered. These were "uniform cortical bone loss", "neck cortical bone loss", "intertrochanteric cortical bone loss" and "uniform trabecular bone loss". The results show that the two "non-uniform cortical bone loss" patterns are more dangerous than the "uniform cortical bone loss" pattern, and that the cortical bone loss in intertrochanteric region is associated with a greater reduction in cortical failure load than the cortical bone loss in the femoral neck. The trabecular bone loss causes a limited decrease in both cortical failure and trabecular failure loads. This research should be helpful to the clinical assessment of femur fracture risk due to age-related bone loss.
