Synthetic biology-based bacterial extracellular vesicles displaying BMP-2 and CXCR4 to ameliorate osteoporosis

Osteoporosis (OP) is a systematic bone disease characterized by low bone mass and fragile bone microarchitecture. Conventional treatment for OP has limited efficacy and long-term toxicity. Synthetic biology makes bacterial extracellular vesicle (BEVs)-based therapeutic strategies a promising alternative for the treatment of OP. Here, we constructed a recombinant probiotics Escherichia coli Nissle 1917-pET28a-ClyA-BMP-2-CXCR4 (ECN-pClyA-BMP-2-CXCR4), in which BMP-2 and CXCR4 were overexpressed in fusion with BEVs surface protein ClyA. Subsequently, we isolated engineered BEVs-BMP-2-CXCR4 (BEVs-BC) for OP therapy. The engineered BEVs-BC exhibited great bone targeting in vivo. In addition, BEVs-BC had good biocompatibility and remarkable ability to promote osteogenic differentiation of BMSCs. Finally, the synthetic biology-based BEVs-BC significantly prevented the OP in an ovariectomized (OVX) mouse model. In conclusion, we constructed BEVs-BC with both bone-targeting and bone-forming in one-step using synthetic biology, which provides an effective strategy for OP and has great potential for industrialization.

Bacterial extracellular vesicles as bioactive nanocarriers for drug delivery: Advances and perspectives

Nanosized extracellular vesicles derived from bacteria contain diverse cargo and transfer intercellular bioactive molecules to cells. Due to their favorable intercellular interactions, cell membrane-derived bacterial extracellular vesicles (BEVs) have great potential to become novel drug delivery platforms. In this review, we summarize the biogenesis mechanism and compositions of various BEVs. In addition, an overview of effective isolation and purification techniques of BEVs is provided. In particular, we focus on the application of BEVs as bioactive nanocarriers for drug delivery. Finally, we summarize the advances and challenges of BEVs after providing a comprehensive discussion in each section. We believe that a deeper understanding of BEVs will open new avenues for their exploitation in drug delivery applications.

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Bacterial extracellular vesicles (BEVs) are excellent nanomaterials as drug delivery systems.

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The unique nanosized structures and biofunctions of BEVs are attractive for their use as nanomedicine platforms.

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BEVs have been investigated as biotherapeutics due to their loading capacity, ease of modification and industrialization.

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This review provides new insights of BEVs in drug delivery applications, discussing potential opportunities and challenges.

Reactive Oxygen Species (ROS)-Responsive Biomaterials for the Treatment of Bone-Related Diseases

Reactive oxygen species (ROS) are the key signaling molecules in many physiological signs of progress and are associated with almost all diseases, such as atherosclerosis, aging, and cancer. Bone is a specific connective tissue consisting of cells, fibers, and mineralized extracellular components, and its quality changes with aging and disease. Growing evidence indicated that overproduced ROS accumulation may disrupt cellular homeostasis in the progress of bone modeling and remodeling, leading to bone metabolic disease. Thus, ROS-responsive biomaterials have attracted great interest from many researchers as promising strategies to realize drug release or targeted therapy for bone-related diseases. Herein, we endeavor to introduce the role of ROS in the bone microenvironment, summarize the mechanism and development of ROS-responsive biomaterials, and their completion and potential for future therapy of bone-related diseases.

Development and validation of the geriatric trauma frailty index for geriatric trauma patients based on electronic hospital records

BACKGROUND

Globally, geriatric patients are the dominant population requiring global medical care. We established a frailty index for geriatric trauma patients by retrospectively analysing electronic hospital records to identify patients with frailty characteristics and poor prognostic outcomes.

METHOD

Data were obtained from 2016 US National Emergency Department Sample and Shanghai Trauma Emergency Medical Association (2015-18). Overall, 141,267 hospitalised geriatric trauma patients (age ≥ 65 years) were included. We used a three-step method to construct geriatric trauma frailty index (GTFI) based on the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnostic codes. Systematic cluster analysis was used. The accuracy of GTFI was verified in national validation cohort, and its applicability to Chinese patients was assessed in local validation cohort.

RESULTS

In development cohort (n = 28,179), frail patients had longer lengths of stay and higher Charlson co-morbidity index than non-frail patients (18.2 ± 12.4 days, 5.59 ± 2.0 versus 5.3 ± 5.3 days, 5.33 ± 1.8, respectively). In national validation cohort (n = 113,089), frail patients had longer lengths of stay (8.5 ± 8.8 days versus 4.5 ± 3.1 days) and higher in-hospital mortality than non-frail patients (2,795, 11.69% versus 589, 0.66%). Areas under the curves for GTFI for length of stay (>14 days) and in-hospital mortality were 0.848 (0.841, 0.854) and 0.885 (0.880, 0.891) in national validation cohort, and were 0.791 (0.779, 0.804) and 0.903 (0.885, 0.922) in local validation cohort (n = 14,827).

CONCLUSIONS

The GTFI helps hospitals and emergency departments to identify geriatric trauma patients with poor prognostic outcomes, and has been proven to be useful in China.

[Quantitative analysis of myelofibrosis and its prognostic significance in patients with myelodysplastic syndrome]

Objective: To quantitatively analyze the reticulin fiber intensity density (RFD) in patients with myelodysplastic syndrome (MDS) by using the computer-aided grid point method, and preliminarily explore its correlation with the prognosis of MDS patients. Methods: Bone marrow (BM) slices from 32 primary MDS patients treated in Tongren Hospital Shanghai Jiao Tong University School of Medicine from February 2017 to December 2019 were observed. Images were taken by the optical microscope imaging system after the Gomori staining. The computer grid marking software was developed according to the principle of the mesh micrometer to assess RFD, meanwhile, the artificial semi-quantitative were used to assess the fibrosis of bone marrow. The co-relation between the above two methods was evaluated, and the relationship between RFD and prognosis of MDS patients were further investigated with Cox regression analysis. Results: Of the patients, there were 17 males and 15 females with a median age of 69 years (32-91 years). The RFD quantitatively analyzed by the computer-based method was positively correlated with the myelofibrosis grade by the artificial semi-quantitative analysis (r=0.497, P=0.004). The RFD in patients diagnosed with MDS complicated with excess blasts (MDS-EB) was significantly higher than that in the non-MDS-EB group((9.55%±0.75%) vs (1.71%±0.23%), P<0.001). Cox regression model analysis showed that the RFD of MDS patients had better prognostic value when compared with the artificial semi-quantitative analysis, which was also a poor prognostic factor (RR=1.337, 95%CI: 1.085-1.648, P=0.006). The overall survival (OS) of patients with RFD>5.54% was significantly shorter than that with RFD≤5.54% (P=0.001). The OS of MDS-EB patients with RFD>9.81% was significantly shorter than that in patients with RFD≤9.81% (P=0.003). Conclusion: Abnormal proliferative fibrosis of bone marrow is a potential high-risk factor for poor prognosis of MDS patients.

Sestamibi Single-Positron Emission Computed Tomography/Diagnostic-quality Computed Tomography for the localization of abnormal parathyroid glands in patients with primary hyperparathyroidism: What clinicopathologic factors affect its accuracy?

PURPOSE

Sestamibi Single-Positron Emission Computed Tomography/Diagnostic-quality Computed Tomography (MIBI-SPECT/CT) is a common technology used for primary hyperparathyroidism (PHPT) localization in clinical practice. However, the clinicopathologic factors affecting the accuracy of MIBI-SPECT/CT and the potential limitations remain unclear.

METHODS

Retrospectively enrolled PHPT patients (n = 280) were analyzed from August 2017 to December 2019.

RESULTS

Of 96 patients with PHPT (mean age, 54 years; 63 females), 17 had discordance between MIBI-SPECT/CT and intraoperative findings. Among the 17 patients with discordance, 58.8% had major discordance, which occurred in most patients with multigland disease (MGD). Compared with concordant patients, discordant patients exhibited increased frequencies of autoimmune thyroid disease (29.4% vs 10.1%, p = 0.035), MDG (41.2% vs 3.8%, p = 0.035), higher PTH (296 pg/mL vs 146 pg/mL; p = 0.012),and lower phosphorus levels (0.77 mmol/L vs 0.90 mmol/L; p = 0.024). MDG (odds ratio [OR], 16.95; 95% CI 2.10-142.86), parathyroid lesion size of 12 mm or less (OR, 6.93; 95% CI 1.41-34.10), and a PTH level higher than 192.5 pg/mL (OR, 12.66; 95% CI 2.17-71.43) were independently associated with discordant MIBI-SPECT/CT results.

CONCLUSION

MGD was most strongly associated with discordance between MIBI-SPECT/CT and intraoperative findings followed by a PTH level higher than 192.5 pg/mL and parathyroid lesion size of 12 mm or less. Surgeons should recognize these potential limitations, which may improve the preoperative procedure by encouraging further localization imaging and promptly facilitate intraoperative troubleshooting.

RANKL from bone marrow adipose lineage cells promotes osteoclast formation and bone loss

Receptor activator of NF-κB ligand (RANKL) is essential for osteoclast formation and bone remodeling. Nevertheless, the cellular source of RANKL for osteoclastogenesis has not been fully uncovered. Different from peripheral adipose tissue, bone marrow (BM) adipose lineage cells originate from bone marrow mesenchymal stromal cells (BMSCs). Here, we demonstrate that adiponectin promoter-driven Cre expression (Adipoq^Cre ) can target bone marrow adipose lineage cells. We cross the Adipoq^Cre mice with rankl^fl/fl mice to conditionally delete RANKL from BM adipose lineage cells. Conditional deletion of RANKL increases cancellous bone mass of long bones in mice by reducing the formation of trabecular osteoclasts and inhibiting bone resorption but does not affect cortical bone thickness or resorption of calcified cartilage. Adipoq^Cre ; rankl^fl/fl mice exhibit resistance to estrogen deficiency and rosiglitazone (ROS)-induced trabecular bone loss but show bone loss induced by unloading. BM adipose lineage cells therefore represent an essential source of RANKL for the formation of trabecula osteoclasts and resorption of cancellous bone during remodeling under physiological and pathological conditions. Targeting bone marrow adiposity is a promising way of preventing pathological bone loss.

Myostatin Promotes Osteoclastogenesis by Regulating Ccdc50 Gene Expression and RANKL-Induced NF-κB and MAPK Pathways

Myostatin is a crucial cytokine that is widely present in skeletal muscle and that negatively regulates the growth and development of muscle cells. Recent research has shown that myostatin might play an essential role in bone metabolism. In RAW264.7 cells and bone marrow monocytes (BMMCs), myostatin activates the expression of the II type receptor ActR II B. Here, we report that myostatin significantly promoted RANKL/M-CSF-induced osteoclastogenesis and activated NF-κB and MAPK pathways in vitro via the Ccdc50 gene. Overexpression of myostatin promoted osteoclastogenesis and osteoclastogenesis-related markers including c-Src, MMP9, CTR, CK, and NFATc1. Specifically, myostatin increased the phosphorylation of Smad2, which led to the activation of NF-κB and MAPK pathways to activate osteoclastogenesis. Ccdc50 was identified as a gene whose expression was highly decreased in osteoclastogenesis upon myostatin treatment, and it could inhibit the function of myostatin in osteoclastogenesis by blocking NF-κB and MAPKs pathways. Our study indicates that myostatin is a promising candidate target for inhibiting RANKL-mediated osteoclastogenesis and might participate in therapy for osteoporosis, and that the Ccdc50 gene plays a significant role in the regulatory process.

The adaptation of sport assessment-patella questionnaire into simplified Chinese version: cross-cultural adaptation, reliability and validity

Background

The original version of Victorian Institute of Sport Assessment-Patella Questionnaire (VISA-P) is developed in English, and aimed to assess the severity of patellar tendinopathy symptoms. Before used in China, it should be translated to Chinese version.

Objectives

Our aim is to make a translation/cross-culturally adaption for the VISA-P into simplified Chinese version (VISA-PC). And primarily validate the VISA-PC in Chinese speaking population.

Methods

The translation process of VISA-P questionnaire into simplified Chinese version (VISP-PC) followed the International recognized guideline. Cross-cultural adaptation was carried out with a clinical measurement study. A total of 128 projects which consisted 33 healthy students, 39 patients with patellar tendinopathy and 56 military students (receive military training as at-risk population) were included into this study. Internal consistency was evaluated with Cronbach’s alpha, and test-retest reliability was assessed with intraclass correlation coefficients (ICCs). Construct validity and floor and ceiling effects were also tested.

Results

The scores were 95.84 ± 5.97 of healthy group, 91.87 ± 9.03 of at-risk group, 62.49 ± 11.39 of pathological group. There is no ceiling and floor effect of VISA-PC. The Cronbach’s alpha (0.895) and ICC (0.986) values showed good internal consistency and reliability. There were high correlations between VISA-PC and Kujala patellofemoral score (r = 0.721). VISA-PC score also had good correlation with the relevant SF-36 items.

Conclusion

The VISA-PC was well translated into simplified Chinese version (VISA-PC), which is reliable and valid for Chinese-speaking patients with patellar tendinopathy.

Level of evidence

II.

Granular measures of agricultural land use influence lake nitrogen and phosphorus differently at macroscales

Agricultural land use is typically associated with high stream nutrient concentrations and increased nutrient loading to lakes. For lakes, evidence for these associations mostly comes from studies on individual lakes or watersheds that relate concentrations of nitrogen (N) or phosphorus (P) to aggregate measures of agricultural land use, such as the proportion of land used for agriculture in a lake's watershed. However, at macroscales (i.e., in hundreds to thousands of lakes across large spatial extents), there is high variability around such relationships and it is unclear whether considering more granular (or detailed) agricultural data, such as fertilizer application, planting of specific crops, or the extent of near-stream cropping, would improve prediction and inform understanding of lake nutrient drivers. Furthermore, it is unclear whether lake N and P would have different relationships to such measures and whether these relationships would vary by region, since regional variation has been observed in prior studies using aggregate measures of agriculture. To address these knowledge gaps, we examined relationships between granular measures of agricultural activity and lake total phosphorus (TP) and total nitrogen (TN) concentrations in 928 lakes and their watersheds in the Northeastern and Midwest U.S. using a Bayesian hierarchical modeling approach. We found that both lake TN and TP concentrations were related to these measures of agriculture, especially near-stream agriculture. The relationships between measures of agriculture and lake TN concentrations were more regionally variable than those for TP. Conversely, TP concentrations were more strongly related to lake-specific measures like depth and watershed hydrology relative to TN. Our finding that lake TN and TP concentrations have different relationships with granular measures of agricultural activity has implications for the design of effective and efficient policy approaches to maintain and improve water quality.

Targeting actin-bundling protein L-plastin as an anabolic therapy for bone loss

The actin-bundling protein L-plastin (LPL) mediates the resorption activity of osteoclasts, but its therapeutic potential in pathological bone loss remains unexplored. Here, we report that LPL knockout mice show increased bone mass and cortical thickness with more mononuclear tartrate-resistant acid phosphatase-positive cells, osteoblasts, CD31^hiEmcn^hi endothelial vessels, and fewer multinuclear osteoclasts in the bone marrow and periosteum. LPL deletion impeded preosteoclasts fusion by inhibiting filopodia formation and increased the number of preosteoclasts, which release platelet-derived growth factor-BB to promote CD31^hiEmcn^hi vessel growth and bone formation. LPL expression is regulated by the phosphatidylinositol 3-kinase/AKT/specific protein 1 axis in response to receptor activator of nuclear factor-κB ligand. Furthermore, we identified an LPL inhibitor, oroxylin A, that could maintain bone mass in ovariectomy-induced osteoporosis and accelerate bone fracture healing in mice. In conclusion, we showed that LPL regulates osteoclasts fusion, and targeting LPL serves as a novel anabolic therapy for pathological bone loss.

Neobavaisoflavone inhibits osteoclastogenesis through blocking RANKL signalling-mediated TRAF6 and c-Src recruitment and NF-κB, MAPK and Akt pathways

Psoralea corylifolia (P corylifolia) has been popularly applied in traditional Chinese medicine decoction for treating osteoporosis and promoting fracture healing since centuries ago. However, the bioactive natural components remain unknown. In this study, applying comprehensive two-dimensional cell membrane chromatographic/C18 column/time-of-flight mass spectrometry (2D CMC/C18 column/TOFMS) system, neobavaisoflavone (NBIF), for the first time, was identified for the bioaffinity with RAW 264.7 cells membranes from the extracts of P corylifolia. Here, we revealed that NBIF inhibited RANKL-mediated osteoclastogenesis in bone marrow monocytes (BMMCs) and RAW264.7 cells dose dependently at the early stage. Moreover, NBIF inhibited osteoclasts function demonstrated by actin ring formation assay and pit-formation assay. With regard to the underlying molecular mechanism, co-immunoprecipitation showed that both the interactions of RANK with TRAF6 and with c-Src were disrupted. In addition, NBIF inhibited the phosphorylation of P50, P65, IκB in NF-κB pathway, ERK, JNK, P38 in MAPKs pathway, AKT in Akt pathway, accompanied with a blockade of calcium oscillation and inactivation of nuclear translocation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1). In vivo, NBIF inhibited osteoclastogenesis, promoted osteogenesis and ameliorated bone loss in ovariectomized mice. In summary, P corylifolia-derived NBIF inhibited RANKL-mediated osteoclastogenesis by suppressing the recruitment of TRAF6 and c-Src to RANK, inactivating NF-κB, MAPKs, and Akt signalling pathways and inhibiting calcium oscillation and NFATc1 translocation. NBIF might serve as a promising candidate for the treatment of osteoclast-associated osteopenic diseases.

One-Step Preparation of an AgNP-nHA@RGO Three-Dimensional Porous Scaffold and Its Application in Infected Bone Defect Treatment

Background

Bactericidal capacity, durable inhibition of biofilm formation, and a three-dimensional (3D) porous structure are the emphases of infected bone defect (IBD) treatment via local scaffold implantation strategy.

Purpose

In this study, silver nanoparticle (AgNP)-loaded nano-hydroxyapatite (nHA)@ reduced graphene oxide (RGO) 3D scaffolds (AHRG scaffolds) were designed to alleviate bone infection, inhibit biofilm formation, and promote bone repair through the synergistic effects of AgNPs, RGO, and nHA.

Materials and Methods

AHRGs were prepared using a one-step preparation method, to create a 3D porous scaffold to facilitate a uniform distribution of AgNPs and nHA. Methicillin-resistant Staphylococcus aureus (MRSA) was used as a model-resistant bacterium, and the effects of different silver loadings on the antimicrobial activity and cytocompatibility of materials were evaluated. Finally, a rabbit IBD model was used to evaluate the therapeutic effect of the AHRG scaffold in vivo.

Results

The results showed successful synthesis of the AHRG scaffold. The ideal 3D porous structure was verified using scanning electron microscopy and transmission electron microscopy, and X-ray photoelectron spectroscopy and selected area electron diffraction measurements revealed uniform distributions of AgNP and nHA. In vitro antibacterial and cytocompatibility indicated that the 4% AHRG scaffolds possessed the most favorable balance of bactericidal properties and cytocompatibility. In vivo evaluation of the IBD model showed promising treatment efficacy of AHRG scaffolds.

Conclusion

The as-fabricated AHRG scaffolds effectively eliminated infection and inhibited biofilm formation. IBD repair was facilitated by the bactericidal properties and 3D porous structure of the AHRG scaffold, suggesting its potential in the treatment of IBDs.

Intensification patterns and the probability of HbA1c goal attainment in Type 2 diabetes mellitus: real-world evidence for the concept of 'intensification inertia'

AIMS

To assess the effects of 'clinical' and 'intensification inertia' by evaluating the impact of different intensification interventions on the probability of HbA_1c goal attainment using real-world data.

METHODS

Electronic health records (Cleveland Clinic, 2005-2016) were used to identify 7389 people with Type 2 diabetes mellitus and HbA_1c ≥53 mmol/mol (≥7.0%), despite a stable regimen of two oral antihyperglycaemic drugs for ≥6 months. The participants were stratified by index HbA_1c and analysed over a 6-month period for pharmacological intensification, and then for 12 additional months for HbA_1c goal attainment (<53 mmol/mol).

RESULTS

The probability of HbA_1c goal attainment (Kaplan-Meier analysis) in the group with index HbA_1c 53-63 mmol/mol (7.0-7.9%) was highest with the addition of oral antidiabetic drugs [57.3% (95% CI 52.1, 62.0)] or glucagon-like peptide-1 receptor agonists [56.7% (95% CI 40.4, 68.6)], in the 64-74 mmol/mol (8.0-8.9%) group with the addition of oral antidiabetic drugs [31.9% (95% CI 25.1, 38.1)] or insulin [30.6% (95% CI 18.3, 41.0)], and in the ≥75 mmol/mol (≥9.0%) group with the addition of glucagon-like peptide-1 receptor agonists [53.0% (95% CI 31.8, 67.6)] or insulin [43.5% (95% CI 36.4, 49.8)].

CONCLUSIONS

Numerical, but not statistically significant, differences in HbA_1c goal attainment probability by type of intensification were most marked in people with the highest index HbA_1c [≥75 mmol/mol (≥9.0%)]; in this group, injectable therapy showed trends toward greater glycaemic control benefits. Additional research into the phenomenon of intensification inertia is warranted.

Longitudinal analysis of atherosclerotic cardiovascular disease risk and healthcare costs in newly diagnosed type 2 diabetes in a real-world setting

AIMS

To assess longitudinal risk for atherosclerotic cardiovascular disease (ASCVD) and cost of healthcare resource utilization over 9 years in patients with or without newly diagnosed type 2 diabetes (T2DM) who had no ASCVD at baseline.

METHODS

This retrospective, longitudinal analysis of a large, nationwide US administrative claims database compared adults with newly diagnosed T2DM (n = 22,468) and a propensity score matched non-T2DM cohort (n = 22,468). Longitudinal risk of ASCVD and total annual healthcare costs were determined. Subgroup analysis was conducted for 3 age categories: 18-44, 45-64, and 65+ years.

RESULTS

From 2006 to 2015, ASCVD was identified in a significantly greater percentage of patients in the T2DM versus non-T2DM cohort (43.2% vs 32.3%; Hazard ratio [HR] = 1.45, P < 0.001). Total annual healthcare cost was markedly higher in T2DM versus non-T2DM cohorts (48.4% higher at year 9). The differences between cohorts were most pronounced in patients aged 18-44 years.

CONCLUSIONS

This 9-year claims-based retrospective, longitudinal analysis showed a higher risk of ASCVD and higher healthcare costs in newly diagnosed T2DM patients versus those without T2DM, with highest relative risk and cost differences observed in younger patients.

[Prediction of short-term prognosis of hepatocellular carcinoma after TACE surgery based on MRI texture analysis technology]

Objective: To explore the feasibility of short-term efficacy prognosis prediction model for HCC patients undergoing transcatheter arterial chemoembolization (TACE) based on MRI-based radiomics technique. Methods: A total of 123 patients with liver cancer who received TACE treatment in Lishui Central Hospital from June 2016 to July 2018 were retrospectively collected, including 90 males and 33 females, with an average age of 24-83 (58±10) years. All the patients were pathologically confirmed as hepatocellular carcinoma and underwent MRI scan before surgery.All patients were followed up 3-4 months after TACE, and further divided into training group (n=85, 42 of which were effective and 43 cases were ineffective) and the validation group (n=38, 19 of which were effective and 19 were ineffective) according to the modified response evaluation criteria in solid tumors (mRECIST). There was no statistical difference in the general information between the two groups of patients, which was comparable. Then, preoperative T(2)WI images were used for radiomics analysis, texture parameters were screened based on R language, and short-term efficacy prediction model of TACE for training group and verification group was constructed. Results: T(2)WI image analysis of each patient received 396 different texture parameters, and further used Lasso dimensionality reduction and 10 times cross-validation screening to obtain 5 characteristic texture parameters, specifically stdDeviation, ClusterProminence_angle135_offset4, Correlation_angle135_offset4, Inertia_angle135_offset4, InverseDifferenceMoment_angle45_offset4. According to the above five texture parameters and their corresponding coefficient values, the corresponding radiomics scores (Radscore) were calculated, and the prediction models of the training group and the verification group were further constructed.It was found that the area under the ROC curve of the training group was 0.812 (95%CI: 0.722-0.901), the sensitivity and specificity were 83.7% and 69.0%, respectively. The area under the ROC curve of the validation group was 0.801 (95%CI:0.654-0.947), and the sensitivity and specificity were 89.5% and 63.2%, respectively. Conclusion: The constructed TACE prediction model in the present study has high prediction accuracy, sensitivity and specificity.The short-term efficacy prognosis prediction model for HCC based on MRI is constructed, stable and reliable.

Guaiacol suppresses osteoclastogenesis by blocking interactions of RANK with TRAF6 and C-Src and inhibiting NF-κB, MAPK and AKT pathways

Angelica sinensis (AS; Dang Gui), a traditional Chinese herb, has for centuries been used for the treatment of bone diseases, including osteoporosis and osteonecrosis. However, the effective ingredient and underlying mechanisms remain elusive. Here, we identified guaiacol as the active component of AS by two‐dimensional cell membrane chromatography/C18 column/time‐of‐flight mass spectrometry (2D CMC/C18 column/TOFMS). Guaiacol suppressed osteoclastogenesis and osteoclast function in bone marrow monocytes (BMMCs) and RAW264.7 cells in vitro in a dose‐dependent manner. Co‐immunoprecipitation indicated that guaiacol blocked RANK‐TRAF6 association and RANK‐C‐Src association. Moreover, guaiacol prevented phosphorylation of p65, p50, IκB (NF‐κB pathway), ERK, JNK, c‐fos, p38 (MAPK pathway) and Akt (AKT pathway), and reduced the expression levels of Cathepsin K, CTR, MMP‐9 and TRAP. Guaiacol also suppressed the expression of nuclear factor of activated T‐cells cytoplasmic 1(NFATc1) and the RANKL‐induced Ca²⁺ oscillation. In vivo, it ameliorated ovariectomy‐induced bone loss by suppressing excessive osteoclastogenesis. Taken together, our findings suggest that guaiacol inhibits RANKL‐induced osteoclastogenesis by blocking the interactions of RANK with TRAF6 and C‐Src, and by suppressing the NF‐κB, MAPK and AKT signalling pathways. Therefore, this compound shows therapeutic potential for osteoclastogenesis‐related bone diseases, including postmenopausal osteoporosis.

l-tetrahydropalmatine suppresses osteoclastogenesis in vivo and in vitro via blocking RANK-TRAF6 interactions and inhibiting NF-κB and MAPK pathways

Bone homeostasis is delicately orchestrated by osteoblasts and osteoclasts. Various pathological bone loss situations result from the overactivated osteoclastogenesis. Receptor activator of nuclear factor κB ligand (RANKL)-activated NF-κB and MAPK pathways is vital for osteoclastogenesis. Here, we for the first time explored the effects of l-tetrahydropalmatine (l-THP), an active alkaloid derived from corydalis, on the formation and function of osteoclasts in vitro and in vivo. In RAW264.7 cells and bone marrow monocytes cells (BMMCs), l-THP inhibited osteoclastic differentiation at the early stage, down-regulated transcription level of osteoclastogenesis-related genes and impaired osteoclasts functions. Mechanically, Western blot showed that l-THP inhibited the phosphorylation of P50, P65, IκB, ERK, JNK and P38, and the electrophoretic mobility shift assay (EMSA) revealed that DNA binding activity of NF-κB was suppressed, ultimately inhibiting the expression of nuclear factor of activated T cells (NFATc1). Besides, Co-immunoprecipitation indicated that l-THP blocked the interactions of RANK and TNF receptor associated factor 6 (TRAF6) at an upstream site. In vivo, l-THP significantly inhibited ovariectomy-induced bone loss and osteoclastogenesis in mice. Collectively, our study demonstrated that l-THP suppressed osteoclastogenesis by blocking RANK-TRAF6 interactions and inhibiting NF-κB and MAPK pathways. l-THP is a promising agent for treating osteoclastogenesis-related diseases such as post-menopausal osteoporosis.

Reversal of Osteoporotic Activity by Endothelial Cell-Secreted Bone Targeting and Biocompatible Exosomes

Exosomes, also known as extracellular vesicles, are naturally occurring, biocompatible, and bioacive nanoparticles ranging from 40 to 150 nm in diameter. Bone-secreted exosomes play important roles in bone homeostasis, the interruption of which can lead to diseases such as osteoporosis, rheumatoid arthritis, and osteopetrosis. Though the relationship between vascular and bone homeostasis has been recognized recently, the role of vascular endothelial cell (EC)-secreted exosomes (EC-Exos) in bone homeostasis is not well understood. Herein, we found that EC-Exos show more efficient bone targeting than osteoblast-derived exosomes or bone marrow mesenchymal stem cell-derived exosomes. We also found that EC-Exos can be internalized by bone marrow-derived macrophages (BMMs) to alter their morphology. EC-Exos can inhibit osteoclast activity in vitro and inhibit osteoporosis in an ovariectomized mouse model. Sequencing of exosome miRNA revealed that miR-155 was highly expressed in EC-Exos-treated BMMs. The miR-155 level in EC-Exos was much higher than that in BMMs and ECs, indicating that miR-155 was endogenous cargo of EC-derived vesicles. Blockage of BMMs miR-155 levels reversed the suppression by EC-Exos of osteoclast induction, confirming that exosomal miR-155 may have therapeutic potential against osteoporosis. Taken together, our findings suggest that EC-Exos may be utilized as a bone targeting and nontoxic nanomedicine for the treatment of bone resorption disorders.

Aligned Carbon Nanotubes Reduce Hypertrophic Scar via Regulating Cell Behavior

Hypertrophic scars, characterized by excessive cell proliferation, disordered cell growth, and aberrant deposition of collagens, could cause significant clinical problems. Herein, aligned carbon nanotubes (ACNTs) were synthesized via chemical vapor deposition, and bulk ACNTs were pulled out from the arrays. The capacity of the ACNTs to reduce hypertrophic scar formation was evaluated both in vitro and in vivo. The results demonstrated that the ACNTs suppressed the overproliferation of fibroblast cells, directed their growth, and inhibited collagen expression in vitro without cell cytotoxicity. Moreover, in vivo evaluation in a rabbit ear model indicated relieved scar hypertrophy after the ACNTs treatment. The gene expression microarray was further used to understand the mechanism, which showed that ACNTs could inhibit the TGFβ pathway to alter the components in the extracellular matrix, cell proliferation, cell cytoskeleton, and cell motility. These findings may provide a potent strategy of using carbon nanotubes in the bioengineering field.

Trends in comorbidity burden and treatment patterns in type 2 diabetes: Longitudinal data from a US cohort from 2006 to 2014

AIMS

To gather real-world data on treatment characteristics and comorbidity progression in patients with newly-diagnosed type 2 diabetes (T2D) and evaluate differences by patient age.

METHODS

Retrospective analysis of a US administrative claims database including 16,950 subjects with newly-diagnosed T2D in 2006 and a baseline Diabetes Complications Severity Index (DCSI) score of 0. Patients were categorized by DCSI score at year 8 (0, 1-2, or ≥3) and comparatively analyzed based on demographic variables, drug usage, and diabetes-related comorbidities.

RESULTS

Year 8 DCSI score distribution was 0 (29.9%), 1-2 (36.2%), and ≥3 (33.9%). The highest DCSI score subgroup (≥3) was characterized by a significantly greater percentage of males, older age at T2D diagnosis, and higher Medicare enrollment. DCSI progressed most rapidly in the oldest age group (≥65). Among all subjects at year 8, insulin use was significantly highest among subjects with DCSI ≥3 compared with those having a lower DCSI. However, for subjects with DCSI ≥3, insulin use was lower among those in the oldest age group (≥65) relative to younger age groups.

CONCLUSIONS

These real-world data suggest a relationship between age at T2D diagnosis and disease progression based on comorbidity burden and lower usage of injectable therapies in older patients.

Inhalation of Hydrogen of Different Concentrations Ameliorates Spinal Cord Injury in Mice by Protecting Spinal Cord Neurons from Apoptosis, Oxidative Injury and Mitochondrial Structure Damages

BACKGROUND/AIMS

Hydrogen selectively neutralizes reactive oxygen species (ROS) and ameliorates various ROS-induced injuries. Spinal cord injury (SCI) is a serious injury to the central nervous system, and secondary SCI is closely related to excessive ROS generation. We hypothesized that hydrogen inhalation ameliorates SCI, and the mechanism of action may be related to the protective effects of hydrogen against oxidative stress, apoptosis, and mitochondrial damage.

METHODS

Mechanically injured spinal cord neurons were incubated with different concentrations of hydrogen in vitro. Immunofluorescence staining and transmission electron microscopy were used to confirm the protective effects of hydrogen. ROS and related proteins were detected with dihydroethidium fluorescence staining, enzyme-linked immunosorbent assays, and western blotting. Terminal deoxynucleotidyl transferase dUTP nick end labeling assays, flow cytometry, and western blotting were used to detect neuronal apoptosis. ATP concentrations, Janus Green B staining, and mitochondrial permeability transition pore (mPTP) status were assessed to investigate mitochondrial damage. RNA sequencing was performed to screen potential target genes of hydrogen application. Hydrogen was administered to mice after spinal cord contusion injury was established for 42 days. The Basso Mouse Scale (BMS) and footprint analyses were used to assess locomotor functions, and immunofluorescence staining of the injured spinal cord segments was performed to detect oxidative stress status.

RESULTS

Spinal cord neurons were preserved by hydrogen administration after mechanical injury in a dose-dependent manner. ROS generation, oxidative stress injury-related markers, and the number of apoptotic neurons were significantly reduced after hydrogen treatment. The ATP production and mPTP function in injured neurons were preserved by hydrogen incubation. The expression levels of Cox8b, Cox6a2, Cox7a1, Hspb7, and Atp2a1 were inhibited by hydrogen treatment. BMS scores and the footprint assessment of mice with SCI were improved by hydrogen inhalation.

CONCLUSIONS

Hydrogen inhalation (75%) ameliorated SCI in vivo and attenuated neuronal mechanical injuries in vitro, and its protective effect on spinal cord neurons was exerted in a dose-dependent manner. The underlying mechanisms included reducing ROS generation and oxidative stress, inhibiting neuronal apoptosis, and restoring mitochondrial construction and function. Cox8b, Cox6a2, Cox7a1, Hspb7, and Atp2a1 were identified as potential target genes of hydrogen treatment.

Mesoporous silica nanoparticles/gelatin porous composite scaffolds with localized and sustained release of vancomycin for treatment of infected bone defects

A highly porous composite scaffold with localized and sustained antibiotic release property for treatment of infected bone defects.

Extracellular matrix protein 1 promotes cell metastasis and glucose metabolism by inducing integrin β4/FAK/SOX2/HIF-1α signaling pathway in gastric cancer

Extracellular matrix protein 1 (ECM1) is related to strong invasiveness and poor prognosis in major malignancies, but the underlying mechanism remains unknown. Here we aimed to elucidate the function of ECM1 on cell metastasis and glucose metabolism in gastric cancer (GC). The level of ECM1 in sera and tissues of patient with GC were positively correlated with tumor invasion and recurrence. Genetic manipulation of ECM1 expression affected cell metastasis and glucose metabolism in GC cell lines. Enhanced ECM1 expression facilitated gene expression levels associated with epithelial-mesenchymal transition (EMT) and glucose metabolism. Interestingly, our results indicated that ECM1 directly interacted with integrin β4 (ITGB4) and activated ITGB4/focal adhesion kinase (FAK)/glycogen synthase kinase 3β signaling pathway, which further induced the expression of transcription factor SOX2. Aberrant expression of SOX2 altered gene expression of EMT factors and glucose metabolism enzymes. Furthermore, SOX2 enhanced hypoxia-inducible factor α (HIF-1α) promoter activity to regulate glucose metabolism. The micro-positron emission tomography/computed tomography imaging of xenograft model showed that ECM1 substantially increased ¹⁸F-fluorodeoxyglucose uptake in xenograft tumors. Using in vivo mouse tail vein injection experiments, ECM1 was also found to increase in lung surface metastasis. These findings provide evidence that ECM1 regulates GC cell metastasis and glucose metabolism by inducing ITGB4/FAK/SOX2/HIF-1α signal pathway and have important implications for the development of therapeutic target to prevent tumor metastasis and recurrence.

Matrine derivate MASM uncovers a novel function for ribosomal protein S5 in osteoclastogenesis and postmenopausal osteoporosis

Postmenopausal osteoporosis (POMP) is a public health problem characterized by decreased bone density and increased fracture risk. Over-activated osteoclastogenesis plays a vital role in POMP. Here we developed a novel bioactive compound MASM (M19) based on sophocarpine. Although it showed no significant effects on osteogenesis and adipogenesis for bone marrow-derived mesenchymal stem cells (BMSCs) in vitro, it could significantly inhibit RANKL/M-CSF induced osteoclastogenesis through suppressing NF-κB, MAPKs and PI3K/Akt pathways in vitro and ameliorate bone loss in ovariectomized mice in vivo. Ribosomal protein s5 (RPS5) has been identified as a target of M19 and regulates PI3K/Akt, NF-κB and MAPKs pathways in osteoclastogenesis. Overexpressions of RPS5 synergistically inhibited osteoclastogenesis with M19 while silencing RPS5 compromised M19 inhibitory effects on osteoclastogenesis in vitro. Among the three pathways, Akt plays a major role in M19 effects. The Akt activator SC₇₉ partially reversed the inhibitory effects on osteoclastogenesis by M19 and RPS5-knocking-down. It indicates that RPS5 serves as a potential candidate target for inhibiting osteoclastogenesis and osteoporosis therapy and M19 is a promising agent for POMP treatment.

Matrine prevents bone loss in ovariectomized mice by inhibiting RANKL-induced osteoclastogenesis

Osteoporosis is a metabolic bone disease characterized by decreased bone density and strength due to excessive loss of bone protein and mineral content. The imbalance between osteogenesis by osteoblasts and osteoclastogenesis by osteoclasts contributes to the pathogenesis of postmenopausal osteoporosis. Estrogen withdrawal leads to increased levels of proinflammatory cytokines. Overactivated osteoclasts by inflammation play a vital role in the imbalance. Matrine is an alkaloid found in plants from the Sophora genus with various pharmacological effects, including anti-inflammatory activity. Here we demonstrate that matrine significantly prevented ovariectomy-induced bone loss and inhibited osteoclastogenesis in vivo with decreased serum levels of TRAcp5b, TNF-α, and IL-6. In vitro matrine significantly inhibited osteoclast differentiation induced by receptor activator for NF-κB ligand (RANKL) and M-CSF in bone marrow monocytes and RAW264.7 cells as demonstrated by tartrate-resistant acid phosphatase (TRAP) staining and actin-ring formation as well as bone resorption through pit formation assays. For molecular mechanisms, matrine abrogated RANKL-induced activation of NF-κB, AKT, and MAPK pathways and suppressed osteoclastogenesis-related marker expression, including matrix metalloproteinase 9, NFATc1, TRAP, C-Src, and cathepsin K. Our study demonstrates that matrine inhibits osteoclastogenesis through modulation of multiple pathways and that matrine is a promising agent in the treatment of osteoclast-related diseases such as osteoporosis.-Chen, X., Zhi, X., Pan, P., Cui, J., Cao, L., Weng, W., Zhou, Q., Wang, L., Zhai, X. Zhao, Q., Hu, H., Huang, B., Su, J. Matrine prevents bone loss in ovariectomized mice by inhibiting RANKL-induced osteoclastogenesis.

Effects of sintering temperature on surface morphology/microstructure, in vitro degradability, mineralization and osteoblast response to magnesium phosphate as biomedical material

Magnesium phosphate (MP) was fabricated using a chemical precipitation method, and the biological performances of MP sintered at different temperatures as a biomedical material was investigated. The results indicated that the densification and crystallinity of MP increased as the sintering temperature increased. As the sintering temperature increased, the degradability of MP in PBS decreased, and the mineralization ability in SBF significantly increased. In addition, the MP sintered at 800 °C (MP8) possessed the lowest degradability and highest mineralization ability. Moreover, the positive response of MG63 cells to MP significantly increased as the sintering temperature increased, and MP8 significantly promoted the cell spreading, proliferation, differentiation and expressions of osteogenic differentiation-related genes. Faster degradation of MP0 resulted in higher pH environments and ion concentrations, which led to negative responses to osteoblasts. However, the appropriate degradation of MP8 resulted in suitable pH environments and ion concentrations, which led to positive responses to osteoblasts. This study demonstrated that the sintering temperature substantially affected the surface morphology/microstructure, degradability and mineralization, and osteoblasts response to magnesium phosphate.

Influences of doping mesoporous magnesium silicate on water absorption, drug release, degradability, apatite-mineralization and primary cells responses to calcium sulfate based bone cements

In this study, composite cements containing mesoporous magnesium silicate (m-MS) and calcium sulfate (CS) were fabricated. The results revealed that the setting time of the m-MS/CS composite cements (m-MSC) slightly prolonged with the increase of m-MS content while the compressive strength suffered a little loss. The doping of m-MS improved the water absorption, drug release (vancomycin) and degradability of the m-MSC in Tris-HCl solution (pH=7.4). In addition, addition of m-MS facilitated the apatite-mineralization of m-MSC in simulated body fluid (SBF), indicating good bioactivity. For cell cultural experiments, the results revealed that the m-MSC promoted the cells adhesion and proliferation, and improved the alkaline phosphatase (ALP) activity of MC3T3-E1 cells, revealing good cytocompatibility. It could be suggested that the m-MSC might be promising cements biomaterials for bone tissue regeneration.

Promotion of in vivo degradability, vascularization and osteogenesis of calcium sulfate-based bone cements containing nanoporous lithium doping magnesium silicate

Nanoporous lithium doping magnesium silicate (nl-MS) was introduced into calcium sulfate hemihydrate to prepare calcium sulfate composite (nl-MSC) bone cements. The introduction of nl-MS improved the in vitro degradability of nl-MSC cements, which could neutralize acidic degradable products of calcium sulfate and prevented the pH from dropping. The cements were implanted into the bone defects of femur bone of rabbits, and the results of histological and immunohistochemical analysis revealed that massive new bone tissue formed in the defects while the cements were degradable, indicating that the osteogenesis and degradability of the nl-MSC cements were much better than the control calcium sulfate dihydrate (CSD) cements. Furthermore, the positive expression of vascular endothelial growth factor and collagen type I for nl-MSC cements was higher than CSD, indicating that addition of nl-MS into the cements enhanced vascularization and osteogenic differentiation. The results suggested that the nl-MSC cements with good biocompatibility and degradability could promote vascularization and osteogenesis, and had great potential to treat bone defects.

The chinese version of achilles tendon total rupture score: cross-cultural adaptation, reliability and validity

Background

The Achilles tendon Total Rupture Score (ATRS), which is originally developed in 2007 in Swedish, is the only patient-reported outcome measure (PROM) for specific outcome assessment of an Achilles tendon rupture.Purpose of this study is to translate and cross-culturally adapt Achilles tendon Total Rupture Score (ATRS) into simplified Chinese, and primarily evaluate the responsiveness, reliability and validity.

Methods

International recognized guideline which was designed by Beaton was followed to make the translation of ATRS from English into simplified Chinese version (CH-ATRS). A prospective cohort study was carried out for the cross-cultural adaptation. There were 112 participants included into the study. Psychometric properties including floor and ceiling effects, Cronbach’s alpha, intraclass correlation coefficient, effect size, standard response mean, and construct validity were tested.

Results

The mean scores of CH-ATRS are 57.42 ± 13.70. No sign of floor or ceiling effect was found of CH-ATRS. High level of internal consistency was supported by the value of Cronbach’s alpha (0.893). ICC (0.979, 95%CI: 0.984-0.993) was high to indicate the high test-retest reliability. Great responsive ness was proved with the high absolute value of ES and SRM (0.84 and 8.98, respectively). The total CH-ATRS score had very good correlation with physical function and body pain subscales of SF-36 (r = −0.758 and r = −0.694, respectively, p < 0.001), while poor correlation with vitality and role physical subscales of SF-36 (r = −0.033 and r = −0.025, respectively, p ≥ 0.05), which supported construct validity of CH-ATRS.

Conclusion

This Chinese version of Achilles tendon Total Rupture Score (CH-ATRS) can be used as a reliable and valid instrument for Achilles tendon rupture assessing in Chinese-speaking population.

Level of evidence II

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-016-0574-8) contains supplementary material, which is available to authorized users.

Controlled release of vancomycin from 3D porous graphene-based composites for dual-purpose treatment of infected bone defects

A vancomycin-loaded reduced graphene oxide/nano-hydroxyapatite (RGO–nHA) 3D porous composite for eradication of bone infection and facilitation of bone regeneration.

Effects of mesoporous calcium magnesium silicate on setting time, compressive strength, apatite formation, degradability and cell behavior to magnesium phosphate based bone cements

Mesoporous calcium magnesium silicate was doped into magnesium phosphate to fabricate magnesium phosphate based composite cements (MBC).

Orthopedics research output from China, USA, UK, Japan, Germany and France: A 10-year survey of the literature

BACKGROUND

In the past decade, researchers have made great progress in the field of Orthopedics. However, the research status of different countries is unclear. To summarize the number of published articles, we assessed the cumulative impact factors in top orthopedic journals. The aims of the study were to measure: 1) the quality and quantity of publications in orthopedics-related journals from China and other five counties, 2) the trend of the number of publications in orthopedics-related journals.

METHODS

The related journals were selected based on the 2014 scientific citation index (SCI) and articles were searched based on the PubMed database. To assess the quantity and quality of research output, the number of publications including clinical trials, randomized controlled trials, meta-analyses, case reports, reviews, citations, impact factors, number of articles in the top 10 journals and most popular journals were recorded.

RESULTS

A total of 143,138 orthopedics articles were published from 2005 to 2014. The USA accounts for 24.9% (35,763/143,138) of the publications, followed by UK (7878/143,138 (5.5%)), Japan (7133/143,138 (5.0%)), Germany (5942/143,138 (4.2%)), China (4143/143,138 (2.9%)) and France (2748/143,138 (1.9%)). The ranking for accumulated impact factors as follows: USA, UK, Japan, Germany, France and China. The mean impact factor's order is USA, China, Germany, Japan, France, UK, and interestingly the mean impact factors in Japan is similar to the Germany in 2005-2014. The USA had the highest percentage of articles in the top 10 journals, while China owns the least. The USA had the highest number of average citations, while Japan had lowest number of average citations.

CONCLUSIONS

According to this study, we can conclude that the USA has had been leading the orthopedics research in the past 10 years. Although China still falls behind, it has made considerable progress in the orthopedics research, not only in quantity but also quality.

LEVEL OF EVIDENCE

IV.

Inhalation of water electrolysis-derived hydrogen ameliorates cerebral ischemia-reperfusion injury in rats - A possible new hydrogen resource for clinical use

Hydrogen is a kind of noble gas with the character to selectively neutralize reactive oxygen species. Former researches proved that low-concentration of hydrogen can be used to ameliorating cerebral ischemia/reperfusion injury. Hydrogen electrolyzed from water has a hydrogen concentration of 66.7%, which is much higher than that used in previous studies. And water electrolysis is a potential new hydrogen resource for regular clinical use. This study was designed and carried out for the determination of safety and neuroprotective effects of water electrolysis-derived hydrogen. Sprague-Dawley rats were used as experimental animals, and middle cerebral artery occlusion was used to make cerebral ischemia/reperfusion model. Pathologically, tissues from rats in hydrogen inhalation group showed no significant difference compared with the control group in HE staining pictures. The blood biochemical findings matched the HE staining result. TTC, Nissl, and TUNEL staining showed the significant improvement of infarction volume, neuron morphology, and neuron apoptosis in rat with hydrogen treatment. Biochemically, hydrogen inhalation decreased brain caspase-3, 3-nitrotyrosine and 8-hydroxy-2-deoxyguanosine-positive cells and inflammation factors concentration. Water electrolysis-derived hydrogen inhalation had neuroprotective effects on cerebral ischemia/reperfusion injury in rats with the effect of suppressing oxidative stress and inflammation, and it is a possible new hydrogen resource to electrolyze water at the bedside clinically.

Drug usage patterns and treatment costs in newly-diagnosed type 2 diabetes mellitus cases, 2007 vs 2012: findings from a large US healthcare claims database analysis

Objective To explore trends in demographics, comorbidities, anti-diabetic drug usage, and healthcare utilization costs in patients with newly-diagnosed type 2 diabetes mellitus (T2DM) using a large US claims database. Methods For the years 2007 and 2012, Truven Health Marketscan Research Databases were used to identify adults with newly-diagnosed T2DM and continuous 12-month enrollment with prescription benefits. Variables examined included patient demographics, comorbidities, inpatient utilization patterns, healthcare costs (inpatient and outpatient), drug costs, and diabetes drug claim patterns. Results Despite an increase in the overall database population between 2007-2012, the incidence of newly-diagnosed T2DM decreased from 1.1% (2007) to 0.65% (2012). Hyperlipidemia and hypertension were the most common comorbidities and increased in prevalence from 2007 to 2012. In 2007, 48.3% of newly-diagnosed T2DM patients had no claims for diabetes medications, compared with 36.2% of patients in 2012. The use of a single oral anti-diabetic drug (OAD) was the most common diabetes medication-related claim (46.2% of patients in 2007; 56.7% of patients in 2012). Among OAD monotherapy users, metformin was the most commonly used and increased from 2007 (74.7% of OAD monotherapy users) to 2012 (90.8%). Decreases were observed for sulfonylureas (14.1% to 6.2%) and thiazolidinediones (7.3% to 0.6%). Insulin, predominantly basal insulin, was used by 3.9% of patients in 2007 and 5.3% of patients in 2012. Mean total annual healthcare costs increased from $13,744 in 2007 to $15,175 in 2012, driven largely by outpatient services, although costs in all individual categories of healthcare services (inpatient and outpatient) increased. Conversely, total drug costs per patient were lower in 2012 compared with 2007. Conclusions Despite a drop in the rate of newly-diagnosed T2DM from 2007 to 2012 in the US, increased total medical costs and comorbidities per individual patient suggest that the clinical and economic trends for T2DM are not declining.

Surgical treatment of calcaneal fractures of Sanders type II and III by a minimally invasive technique using a locking plate

The aim of the present study was to investigate the outcomes of surgical treatment of calcaneal fractures of Sanders type II and III using a minimally invasive technique and a locking plate. We reviewed 33 feet in 33 consecutive patients with Sanders type II and III calcaneal fractures who had undergone a minimally invasive technique using percutaneous reduction and locking plates. All operations were performed by the same surgeons. The postoperative evaluation included radiographs, determination of restoration of Böhler's angle and Gissane's angle, and administration of the American Orthopaedic Foot and Ankle Society ankle-hind foot scale, Maryland Foot Score, and visual analog scale of pain. The mean visual analog scale score was 1.6 ± 1.4 when radiographic fracture healing was observed. The median functional score of the 33 patients (33 feet) reached 82 (interquartile range 80 to 99) at the last follow-up evaluation according to the American Orthopaedic Foot and Ankle Society ankle-hind foot scale and 89 (interquartile range 80 to 99) according to Maryland Foot Score. All cases achieved restoration of a normal Böhler's angle and Gissane's angle. Postoperative superficial infections occurred in 2 patients, subtalar arthritis developed in 2, and no soft tissue necrosis was observed. For Sanders type II and III fractures of the calcaneus bone, treatment with a minimally invasive technique combining percutaneous reduction and locking plate fixation provided satisfactory clinical results, with a lower incidence of complications. However, longer term studies with a larger sample size and more randomized controlled trials are required to define the superiority of our minimally invasive technique compared with conventional surgical treatment of calcaneal fractures.